apply.c

   1 /*
   2  * apply.c
   3  *
   4  * Copyright (C) Linus Torvalds, 2005
   5  *
   6  * This applies patches on top of some (arbitrary) version of the SCM.
   7  *
   8  */
   9
  10 #include "cache.h"
  11 #include "config.h"
  12 #include "blob.h"
  13 #include "delta.h"
  14 #include "diff.h"
  15 #include "dir.h"
  16 #include "xdiff-interface.h"
  17 #include "ll-merge.h"
  18 #include "lockfile.h"
  19 #include "parse-options.h"
  20 #include "quote.h"
  21 #include "rerere.h"
  22 #include "apply.h"
  23
  24 static void git_apply_config(void)
  25 {
  26         git_config_get_string_const("apply.whitespace", &apply_default_whitespace);
  27         git_config_get_string_const("apply.ignorewhitespace", &apply_default_ignorewhitespace);
  28         git_config(git_default_config, NULL);
  29 }
  30
  31 static int parse_whitespace_option(struct apply_state *state, const char *option)
  32 {
  33         if (!option) {
  34                 state->ws_error_action = warn_on_ws_error;
  35                 return 0;
  36         }
  37         if (!strcmp(option, "warn")) {
  38                 state->ws_error_action = warn_on_ws_error;
  39                 return 0;
  40         }
  41         if (!strcmp(option, "nowarn")) {
  42                 state->ws_error_action = nowarn_ws_error;
  43                 return 0;
  44         }
  45         if (!strcmp(option, "error")) {
  46                 state->ws_error_action = die_on_ws_error;
  47                 return 0;
  48         }
  49         if (!strcmp(option, "error-all")) {
  50                 state->ws_error_action = die_on_ws_error;
  51                 state->squelch_whitespace_errors = 0;
  52                 return 0;
  53         }
  54         if (!strcmp(option, "strip") || !strcmp(option, "fix")) {
  55                 state->ws_error_action = correct_ws_error;
  56                 return 0;
  57         }
  58         return error(_("unrecognized whitespace option '%s'"), option);
  59 }
  60
  61 static int parse_ignorewhitespace_option(struct apply_state *state,
  62                                                  const char *option)
  63 {
  64         if (!option || !strcmp(option, "no") ||
  65             !strcmp(option, "false") || !strcmp(option, "never") ||
  66             !strcmp(option, "none")) {
  67                 state->ws_ignore_action = ignore_ws_none;
  68                 return 0;
  69         }
  70         if (!strcmp(option, "change")) {
  71                 state->ws_ignore_action = ignore_ws_change;
  72                 return 0;
  73         }
  74         return error(_("unrecognized whitespace ignore option '%s'"), option);
  75 }
  76
  77 int init_apply_state(struct apply_state *state,
  78                      const char *prefix,
  79                      struct lock_file *lock_file)
  80 {
  81         memset(state, 0, sizeof(*state));
  82         state->prefix = prefix;
  83         state->lock_file = lock_file;
  84         state->newfd = -1;
  85         state->apply = 1;
  86         state->line_termination = '\n';
  87         state->p_value = 1;
  88         state->p_context = UINT_MAX;
  89         state->squelch_whitespace_errors = 5;
  90         state->ws_error_action = warn_on_ws_error;
  91         state->ws_ignore_action = ignore_ws_none;
  92         state->linenr = 1;
  93         string_list_init(&state->fn_table, 0);
  94         string_list_init(&state->limit_by_name, 0);
  95         string_list_init(&state->symlink_changes, 0);
  96         strbuf_init(&state->root, 0);
  97
  98         git_apply_config();
  99         if (apply_default_whitespace && parse_whitespace_option(state, apply_default_whitespace))
 100                 return -1;
 101         if (apply_default_ignorewhitespace && parse_ignorewhitespace_option(state, apply_default_ignorewhitespace))
 102                 return -1;
 103         return 0;
 104 }
 105
 106 void clear_apply_state(struct apply_state *state)
 107 {
 108         string_list_clear(&state->limit_by_name, 0);
 109         string_list_clear(&state->symlink_changes, 0);
 110         strbuf_release(&state->root);
 111
 112         /* &state->fn_table is cleared at the end of apply_patch() */
 113 }
 114
 115 static void mute_routine(const char *msg, va_list params)
 116 {
 117         /* do nothing */
 118 }
 119
 120 int check_apply_state(struct apply_state *state, int force_apply)
 121 {
 122         int is_not_gitdir = !startup_info->have_repository;
 123
 124         if (state->apply_with_reject && state->threeway)
 125                 return error(_("--reject and --3way cannot be used together."));
 126         if (state->cached && state->threeway)
 127                 return error(_("--cached and --3way cannot be used together."));
 128         if (state->threeway) {
 129                 if (is_not_gitdir)
 130                         return error(_("--3way outside a repository"));
 131                 state->check_index = 1;
 132         }
 133         if (state->apply_with_reject) {
 134                 state->apply = 1;
 135                 if (state->apply_verbosity == verbosity_normal)
 136                         state->apply_verbosity = verbosity_verbose;
 137         }
 138         if (!force_apply && (state->diffstat || state->numstat || state->summary || state->check || state->fake_ancestor))
 139                 state->apply = 0;
 140         if (state->check_index && is_not_gitdir)
 141                 return error(_("--index outside a repository"));
 142         if (state->cached) {
 143                 if (is_not_gitdir)
 144                         return error(_("--cached outside a repository"));
 145                 state->check_index = 1;
 146         }
 147         if (state->check_index)
 148                 state->unsafe_paths = 0;
 149         if (!state->lock_file)
 150                 return error("BUG: state->lock_file should not be NULL");
 151
 152         if (state->apply_verbosity <= verbosity_silent) {
 153                 state->saved_error_routine = get_error_routine();
 154                 state->saved_warn_routine = get_warn_routine();
 155                 set_error_routine(mute_routine);
 156                 set_warn_routine(mute_routine);
 157         }
 158
 159         return 0;
 160 }
 161
 162 static void set_default_whitespace_mode(struct apply_state *state)
 163 {
 164         if (!state->whitespace_option && !apply_default_whitespace)
 165                 state->ws_error_action = (state->apply ? warn_on_ws_error : nowarn_ws_error);
 166 }
 167
 168 /*
 169  * This represents one "hunk" from a patch, starting with
 170  * "@@ -oldpos,oldlines +newpos,newlines @@" marker.  The
 171  * patch text is pointed at by patch, and its byte length
 172  * is stored in size.  leading and trailing are the number
 173  * of context lines.
 174  */
 175 struct fragment {
 176         unsigned long leading, trailing;
 177         unsigned long oldpos, oldlines;
 178         unsigned long newpos, newlines;
 179         /*
 180          * 'patch' is usually borrowed from buf in apply_patch(),
 181          * but some codepaths store an allocated buffer.
 182          */
 183         const char *patch;
 184         unsigned free_patch:1,
 185                 rejected:1;
 186         int size;
 187         int linenr;
 188         struct fragment *next;
 189 };
 190
 191 /*
 192  * When dealing with a binary patch, we reuse "leading" field
 193  * to store the type of the binary hunk, either deflated "delta"
 194  * or deflated "literal".
 195  */
 196 #define binary_patch_method leading
 197 #define BINARY_DELTA_DEFLATED   1
 198 #define BINARY_LITERAL_DEFLATED 2
 199
 200 /*
 201  * This represents a "patch" to a file, both metainfo changes
 202  * such as creation/deletion, filemode and content changes represented
 203  * as a series of fragments.
 204  */
 205 struct patch {
 206         char *new_name, *old_name, *def_name;
 207         unsigned int old_mode, new_mode;
 208         int is_new, is_delete;  /* -1 = unknown, 0 = false, 1 = true */
 209         int rejected;
 210         unsigned ws_rule;
 211         int lines_added, lines_deleted;
 212         int score;
 213         int extension_linenr; /* first line specifying delete/new/rename/copy */
 214         unsigned int is_toplevel_relative:1;
 215         unsigned int inaccurate_eof:1;
 216         unsigned int is_binary:1;
 217         unsigned int is_copy:1;
 218         unsigned int is_rename:1;
 219         unsigned int recount:1;
 220         unsigned int conflicted_threeway:1;
 221         unsigned int direct_to_threeway:1;
 222         unsigned int crlf_in_old:1;
 223         struct fragment *fragments;
 224         char *result;
 225         size_t resultsize;
 226         char old_sha1_prefix[41];
 227         char new_sha1_prefix[41];
 228         struct patch *next;
 229
 230         /* three-way fallback result */
 231         struct object_id threeway_stage[3];
 232 };
 233
 234 static void free_fragment_list(struct fragment *list)
 235 {
 236         while (list) {
 237                 struct fragment *next = list->next;
 238                 if (list->free_patch)
 239                         free((char *)list->patch);
 240                 free(list);
 241                 list = next;
 242         }
 243 }
 244
 245 static void free_patch(struct patch *patch)
 246 {
 247         free_fragment_list(patch->fragments);
 248         free(patch->def_name);
 249         free(patch->old_name);
 250         free(patch->new_name);
 251         free(patch->result);
 252         free(patch);
 253 }
 254
 255 static void free_patch_list(struct patch *list)
 256 {
 257         while (list) {
 258                 struct patch *next = list->next;
 259                 free_patch(list);
 260                 list = next;
 261         }
 262 }
 263
 264 /*
 265  * A line in a file, len-bytes long (includes the terminating LF,
 266  * except for an incomplete line at the end if the file ends with
 267  * one), and its contents hashes to 'hash'.
 268  */
 269 struct line {
 270         size_t len;
 271         unsigned hash : 24;
 272         unsigned flag : 8;
 273 #define LINE_COMMON     1
 274 #define LINE_PATCHED    2
 275 };
 276
 277 /*
 278  * This represents a "file", which is an array of "lines".
 279  */
 280 struct image {
 281         char *buf;
 282         size_t len;
 283         size_t nr;
 284         size_t alloc;
 285         struct line *line_allocated;
 286         struct line *line;
 287 };
 288
 289 static uint32_t hash_line(const char *cp, size_t len)
 290 {
 291         size_t i;
 292         uint32_t h;
 293         for (i = 0, h = 0; i < len; i++) {
 294                 if (!isspace(cp[i])) {
 295                         h = h * 3 + (cp[i] & 0xff);
 296                 }
 297         }
 298         return h;
 299 }
 300
 301 /*
 302  * Compare lines s1 of length n1 and s2 of length n2, ignoring
 303  * whitespace difference. Returns 1 if they match, 0 otherwise
 304  */
 305 static int fuzzy_matchlines(const char *s1, size_t n1,
 306                             const char *s2, size_t n2)
 307 {
 308         const char *end1 = s1 + n1;
 309         const char *end2 = s2 + n2;
 310
 311         /* ignore line endings */
 312         while (s1 < end1 && (end1[-1] == '\r' || end1[-1] == '\n'))
 313                 end1--;
 314         while (s2 < end2 && (end2[-1] == '\r' || end2[-1] == '\n'))
 315                 end2--;
 316
 317         while (s1 < end1 && s2 < end2) {
 318                 if (isspace(*s1)) {
 319                         /*
 320                          * Skip whitespace. We check on both buffers
 321                          * because we don't want "a b" to match "ab".
 322                          */
 323                         if (!isspace(*s2))
 324                                 return 0;
 325                         while (s1 < end1 && isspace(*s1))
 326                                 s1++;
 327                         while (s2 < end2 && isspace(*s2))
 328                                 s2++;
 329                 } else if (*s1++ != *s2++)
 330                         return 0;
 331         }
 332
 333         /* If we reached the end on one side only, lines don't match. */
 334         return s1 == end1 && s2 == end2;
 335 }
 336
 337 static void add_line_info(struct image *img, const char *bol, size_t len, unsigned flag)
 338 {
 339         ALLOC_GROW(img->line_allocated, img->nr + 1, img->alloc);
 340         img->line_allocated[img->nr].len = len;
 341         img->line_allocated[img->nr].hash = hash_line(bol, len);
 342         img->line_allocated[img->nr].flag = flag;
 343         img->nr++;
 344 }
 345
 346 /*
 347  * "buf" has the file contents to be patched (read from various sources).
 348  * attach it to "image" and add line-based index to it.
 349  * "image" now owns the "buf".
 350  */
 351 static void prepare_image(struct image *image, char *buf, size_t len,
 352                           int prepare_linetable)
 353 {
 354         const char *cp, *ep;
 355
 356         memset(image, 0, sizeof(*image));
 357         image->buf = buf;
 358         image->len = len;
 359
 360         if (!prepare_linetable)
 361                 return;
 362
 363         ep = image->buf + image->len;
 364         cp = image->buf;
 365         while (cp < ep) {
 366                 const char *next;
 367                 for (next = cp; next < ep && *next != '\n'; next++)
 368                         ;
 369                 if (next < ep)
 370                         next++;
 371                 add_line_info(image, cp, next - cp, 0);
 372                 cp = next;
 373         }
 374         image->line = image->line_allocated;
 375 }
 376
 377 static void clear_image(struct image *image)
 378 {
 379         free(image->buf);
 380         free(image->line_allocated);
 381         memset(image, 0, sizeof(*image));
 382 }
 383
 384 /* fmt must contain _one_ %s and no other substitution */
 385 static void say_patch_name(FILE *output, const char *fmt, struct patch *patch)
 386 {
 387         struct strbuf sb = STRBUF_INIT;
 388
 389         if (patch->old_name && patch->new_name &&
 390             strcmp(patch->old_name, patch->new_name)) {
 391                 quote_c_style(patch->old_name, &sb, NULL, 0);
 392                 strbuf_addstr(&sb, " => ");
 393                 quote_c_style(patch->new_name, &sb, NULL, 0);
 394         } else {
 395                 const char *n = patch->new_name;
 396                 if (!n)
 397                         n = patch->old_name;
 398                 quote_c_style(n, &sb, NULL, 0);
 399         }
 400         fprintf(output, fmt, sb.buf);
 401         fputc('\n', output);
 402         strbuf_release(&sb);
 403 }
 404
 405 #define SLOP (16)
 406
 407 static int read_patch_file(struct strbuf *sb, int fd)
 408 {
 409         if (strbuf_read(sb, fd, 0) < 0)
 410                 return error_errno("git apply: failed to read");
 411
 412         /*
 413          * Make sure that we have some slop in the buffer
 414          * so that we can do speculative "memcmp" etc, and
 415          * see to it that it is NUL-filled.
 416          */
 417         strbuf_grow(sb, SLOP);
 418         memset(sb->buf + sb->len, 0, SLOP);
 419         return 0;
 420 }
 421
 422 static unsigned long linelen(const char *buffer, unsigned long size)
 423 {
 424         unsigned long len = 0;
 425         while (size--) {
 426                 len++;
 427                 if (*buffer++ == '\n')
 428                         break;
 429         }
 430         return len;
 431 }
 432
 433 static int is_dev_null(const char *str)
 434 {
 435         return skip_prefix(str, "/dev/null", &str) && isspace(*str);
 436 }
 437
 438 #define TERM_SPACE      1
 439 #define TERM_TAB        2
 440
 441 static int name_terminate(int c, int terminate)
 442 {
 443         if (c == ' ' && !(terminate & TERM_SPACE))
 444                 return 0;
 445         if (c == '\t' && !(terminate & TERM_TAB))
 446                 return 0;
 447
 448         return 1;
 449 }
 450
 451 /* remove double slashes to make --index work with such filenames */
 452 static char *squash_slash(char *name)
 453 {
 454         int i = 0, j = 0;
 455
 456         if (!name)
 457                 return NULL;
 458
 459         while (name[i]) {
 460                 if ((name[j++] = name[i++]) == '/')
 461                         while (name[i] == '/')
 462                                 i++;
 463         }
 464         name[j] = '\0';
 465         return name;
 466 }
 467
 468 static char *find_name_gnu(struct apply_state *state,
 469                            const char *line,
 470                            const char *def,
 471                            int p_value)
 472 {
 473         struct strbuf name = STRBUF_INIT;
 474         char *cp;
 475
 476         /*
 477          * Proposed "new-style" GNU patch/diff format; see
 478          * http://marc.info/?l=git&m=112927316408690&w=2
 479          */
 480         if (unquote_c_style(&name, line, NULL)) {
 481                 strbuf_release(&name);
 482                 return NULL;
 483         }
 484
 485         for (cp = name.buf; p_value; p_value--) {
 486                 cp = strchr(cp, '/');
 487                 if (!cp) {
 488                         strbuf_release(&name);
 489                         return NULL;
 490                 }
 491                 cp++;
 492         }
 493
 494         strbuf_remove(&name, 0, cp - name.buf);
 495         if (state->root.len)
 496                 strbuf_insert(&name, 0, state->root.buf, state->root.len);
 497         return squash_slash(strbuf_detach(&name, NULL));
 498 }
 499
 500 static size_t sane_tz_len(const char *line, size_t len)
 501 {
 502         const char *tz, *p;
 503
 504         if (len < strlen(" +0500") || line[len-strlen(" +0500")] != ' ')
 505                 return 0;
 506         tz = line + len - strlen(" +0500");
 507
 508         if (tz[1] != '+' && tz[1] != '-')
 509                 return 0;
 510
 511         for (p = tz + 2; p != line + len; p++)
 512                 if (!isdigit(*p))
 513                         return 0;
 514
 515         return line + len - tz;
 516 }
 517
 518 static size_t tz_with_colon_len(const char *line, size_t len)
 519 {
 520         const char *tz, *p;
 521
 522         if (len < strlen(" +08:00") || line[len - strlen(":00")] != ':')
 523                 return 0;
 524         tz = line + len - strlen(" +08:00");
 525
 526         if (tz[0] != ' ' || (tz[1] != '+' && tz[1] != '-'))
 527                 return 0;
 528         p = tz + 2;
 529         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 530             !isdigit(*p++) || !isdigit(*p++))
 531                 return 0;
 532
 533         return line + len - tz;
 534 }
 535
 536 static size_t date_len(const char *line, size_t len)
 537 {
 538         const char *date, *p;
 539
 540         if (len < strlen("72-02-05") || line[len-strlen("-05")] != '-')
 541                 return 0;
 542         p = date = line + len - strlen("72-02-05");
 543
 544         if (!isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
 545             !isdigit(*p++) || !isdigit(*p++) || *p++ != '-' ||
 546             !isdigit(*p++) || !isdigit(*p++))   /* Not a date. */
 547                 return 0;
 548
 549         if (date - line >= strlen("19") &&
 550             isdigit(date[-1]) && isdigit(date[-2]))     /* 4-digit year */
 551                 date -= strlen("19");
 552
 553         return line + len - date;
 554 }
 555
 556 static size_t short_time_len(const char *line, size_t len)
 557 {
 558         const char *time, *p;
 559
 560         if (len < strlen(" 07:01:32") || line[len-strlen(":32")] != ':')
 561                 return 0;
 562         p = time = line + len - strlen(" 07:01:32");
 563
 564         /* Permit 1-digit hours? */
 565         if (*p++ != ' ' ||
 566             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 567             !isdigit(*p++) || !isdigit(*p++) || *p++ != ':' ||
 568             !isdigit(*p++) || !isdigit(*p++))   /* Not a time. */
 569                 return 0;
 570
 571         return line + len - time;
 572 }
 573
 574 static size_t fractional_time_len(const char *line, size_t len)
 575 {
 576         const char *p;
 577         size_t n;
 578
 579         /* Expected format: 19:41:17.620000023 */
 580         if (!len || !isdigit(line[len - 1]))
 581                 return 0;
 582         p = line + len - 1;
 583
 584         /* Fractional seconds. */
 585         while (p > line && isdigit(*p))
 586                 p--;
 587         if (*p != '.')
 588                 return 0;
 589
 590         /* Hours, minutes, and whole seconds. */
 591         n = short_time_len(line, p - line);
 592         if (!n)
 593                 return 0;
 594
 595         return line + len - p + n;
 596 }
 597
 598 static size_t trailing_spaces_len(const char *line, size_t len)
 599 {
 600         const char *p;
 601
 602         /* Expected format: ' ' x (1 or more)  */
 603         if (!len || line[len - 1] != ' ')
 604                 return 0;
 605
 606         p = line + len;
 607         while (p != line) {
 608                 p--;
 609                 if (*p != ' ')
 610                         return line + len - (p + 1);
 611         }
 612
 613         /* All spaces! */
 614         return len;
 615 }
 616
 617 static size_t diff_timestamp_len(const char *line, size_t len)
 618 {
 619         const char *end = line + len;
 620         size_t n;
 621
 622         /*
 623          * Posix: 2010-07-05 19:41:17
 624          * GNU: 2010-07-05 19:41:17.620000023 -0500
 625          */
 626
 627         if (!isdigit(end[-1]))
 628                 return 0;
 629
 630         n = sane_tz_len(line, end - line);
 631         if (!n)
 632                 n = tz_with_colon_len(line, end - line);
 633         end -= n;
 634
 635         n = short_time_len(line, end - line);
 636         if (!n)
 637                 n = fractional_time_len(line, end - line);
 638         end -= n;
 639
 640         n = date_len(line, end - line);
 641         if (!n) /* No date.  Too bad. */
 642                 return 0;
 643         end -= n;
 644
 645         if (end == line)        /* No space before date. */
 646                 return 0;
 647         if (end[-1] == '\t') {  /* Success! */
 648                 end--;
 649                 return line + len - end;
 650         }
 651         if (end[-1] != ' ')     /* No space before date. */
 652                 return 0;
 653
 654         /* Whitespace damage. */
 655         end -= trailing_spaces_len(line, end - line);
 656         return line + len - end;
 657 }
 658
 659 static char *find_name_common(struct apply_state *state,
 660                               const char *line,
 661                               const char *def,
 662                               int p_value,
 663                               const char *end,
 664                               int terminate)
 665 {
 666         int len;
 667         const char *start = NULL;
 668
 669         if (p_value == 0)
 670                 start = line;
 671         while (line != end) {
 672                 char c = *line;
 673
 674                 if (!end && isspace(c)) {
 675                         if (c == '\n')
 676                                 break;
 677                         if (name_terminate(c, terminate))
 678                                 break;
 679                 }
 680                 line++;
 681                 if (c == '/' && !--p_value)
 682                         start = line;
 683         }
 684         if (!start)
 685                 return squash_slash(xstrdup_or_null(def));
 686         len = line - start;
 687         if (!len)
 688                 return squash_slash(xstrdup_or_null(def));
 689
 690         /*
 691          * Generally we prefer the shorter name, especially
 692          * if the other one is just a variation of that with
 693          * something else tacked on to the end (ie "file.orig"
 694          * or "file~").
 695          */
 696         if (def) {
 697                 int deflen = strlen(def);
 698                 if (deflen < len && !strncmp(start, def, deflen))
 699                         return squash_slash(xstrdup(def));
 700         }
 701
 702         if (state->root.len) {
 703                 char *ret = xstrfmt("%s%.*s", state->root.buf, len, start);
 704                 return squash_slash(ret);
 705         }
 706
 707         return squash_slash(xmemdupz(start, len));
 708 }
 709
 710 static char *find_name(struct apply_state *state,
 711                        const char *line,
 712                        char *def,
 713                        int p_value,
 714                        int terminate)
 715 {
 716         if (*line == '"') {
 717                 char *name = find_name_gnu(state, line, def, p_value);
 718                 if (name)
 719                         return name;
 720         }
 721
 722         return find_name_common(state, line, def, p_value, NULL, terminate);
 723 }
 724
 725 static char *find_name_traditional(struct apply_state *state,
 726                                    const char *line,
 727                                    char *def,
 728                                    int p_value)
 729 {
 730         size_t len;
 731         size_t date_len;
 732
 733         if (*line == '"') {
 734                 char *name = find_name_gnu(state, line, def, p_value);
 735                 if (name)
 736                         return name;
 737         }
 738
 739         len = strchrnul(line, '\n') - line;
 740         date_len = diff_timestamp_len(line, len);
 741         if (!date_len)
 742                 return find_name_common(state, line, def, p_value, NULL, TERM_TAB);
 743         len -= date_len;
 744
 745         return find_name_common(state, line, def, p_value, line + len, 0);
 746 }
 747
 748 /*
 749  * Given the string after "--- " or "+++ ", guess the appropriate
 750  * p_value for the given patch.
 751  */
 752 static int guess_p_value(struct apply_state *state, const char *nameline)
 753 {
 754         char *name, *cp;
 755         int val = -1;
 756
 757         if (is_dev_null(nameline))
 758                 return -1;
 759         name = find_name_traditional(state, nameline, NULL, 0);
 760         if (!name)
 761                 return -1;
 762         cp = strchr(name, '/');
 763         if (!cp)
 764                 val = 0;
 765         else if (state->prefix) {
 766                 /*
 767                  * Does it begin with "a/$our-prefix" and such?  Then this is
 768                  * very likely to apply to our directory.
 769                  */
 770                 if (starts_with(name, state->prefix))
 771                         val = count_slashes(state->prefix);
 772                 else {
 773                         cp++;
 774                         if (starts_with(cp, state->prefix))
 775                                 val = count_slashes(state->prefix) + 1;
 776                 }
 777         }
 778         free(name);
 779         return val;
 780 }
 781
 782 /*
 783  * Does the ---/+++ line have the POSIX timestamp after the last HT?
 784  * GNU diff puts epoch there to signal a creation/deletion event.  Is
 785  * this such a timestamp?
 786  */
 787 static int has_epoch_timestamp(const char *nameline)
 788 {
 789         /*
 790          * We are only interested in epoch timestamp; any non-zero
 791          * fraction cannot be one, hence "(\.0+)?" in the regexp below.
 792          * For the same reason, the date must be either 1969-12-31 or
 793          * 1970-01-01, and the seconds part must be "00".
 794          */
 795         const char stamp_regexp[] =
 796                 "^[0-2][0-9]:([0-5][0-9]):00(\\.0+)?"
 797                 " "
 798                 "([-+][0-2][0-9]:?[0-5][0-9])\n";
 799         const char *timestamp = NULL, *cp, *colon;
 800         static regex_t *stamp;
 801         regmatch_t m[10];
 802         int zoneoffset, epoch_hour, hour, minute;
 803         int status;
 804
 805         for (cp = nameline; *cp != '\n'; cp++) {
 806                 if (*cp == '\t')
 807                         timestamp = cp + 1;
 808         }
 809         if (!timestamp)
 810                 return 0;
 811
 812         /*
 813          * YYYY-MM-DD hh:mm:ss must be from either 1969-12-31
 814          * (west of GMT) or 1970-01-01 (east of GMT)
 815          */
 816         if (skip_prefix(timestamp, "1969-12-31 ", &timestamp))
 817                 epoch_hour = 24;
 818         else if (skip_prefix(timestamp, "1970-01-01 ", &timestamp))
 819                 epoch_hour = 0;
 820         else
 821                 return 0;
 822
 823         if (!stamp) {
 824                 stamp = xmalloc(sizeof(*stamp));
 825                 if (regcomp(stamp, stamp_regexp, REG_EXTENDED)) {
 826                         warning(_("Cannot prepare timestamp regexp %s"),
 827                                 stamp_regexp);
 828                         return 0;
 829                 }
 830         }
 831
 832         status = regexec(stamp, timestamp, ARRAY_SIZE(m), m, 0);
 833         if (status) {
 834                 if (status != REG_NOMATCH)
 835                         warning(_("regexec returned %d for input: %s"),
 836                                 status, timestamp);
 837                 return 0;
 838         }
 839
 840         hour = strtol(timestamp, NULL, 10);
 841         minute = strtol(timestamp + m[1].rm_so, NULL, 10);
 842
 843         zoneoffset = strtol(timestamp + m[3].rm_so + 1, (char **) &colon, 10);
 844         if (*colon == ':')
 845                 zoneoffset = zoneoffset * 60 + strtol(colon + 1, NULL, 10);
 846         else
 847                 zoneoffset = (zoneoffset / 100) * 60 + (zoneoffset % 100);
 848         if (timestamp[m[3].rm_so] == '-')
 849                 zoneoffset = -zoneoffset;
 850
 851         return hour * 60 + minute - zoneoffset == epoch_hour * 60;
 852 }
 853
 854 /*
 855  * Get the name etc info from the ---/+++ lines of a traditional patch header
 856  *
 857  * FIXME! The end-of-filename heuristics are kind of screwy. For existing
 858  * files, we can happily check the index for a match, but for creating a
 859  * new file we should try to match whatever "patch" does. I have no idea.
 860  */
 861 static int parse_traditional_patch(struct apply_state *state,
 862                                    const char *first,
 863                                    const char *second,
 864                                    struct patch *patch)
 865 {
 866         char *name;
 867
 868         first += 4;     /* skip "--- " */
 869         second += 4;    /* skip "+++ " */
 870         if (!state->p_value_known) {
 871                 int p, q;
 872                 p = guess_p_value(state, first);
 873                 q = guess_p_value(state, second);
 874                 if (p < 0) p = q;
 875                 if (0 <= p && p == q) {
 876                         state->p_value = p;
 877                         state->p_value_known = 1;
 878                 }
 879         }
 880         if (is_dev_null(first)) {
 881                 patch->is_new = 1;
 882                 patch->is_delete = 0;
 883                 name = find_name_traditional(state, second, NULL, state->p_value);
 884                 patch->new_name = name;
 885         } else if (is_dev_null(second)) {
 886                 patch->is_new = 0;
 887                 patch->is_delete = 1;
 888                 name = find_name_traditional(state, first, NULL, state->p_value);
 889                 patch->old_name = name;
 890         } else {
 891                 char *first_name;
 892                 first_name = find_name_traditional(state, first, NULL, state->p_value);
 893                 name = find_name_traditional(state, second, first_name, state->p_value);
 894                 free(first_name);
 895                 if (has_epoch_timestamp(first)) {
 896                         patch->is_new = 1;
 897                         patch->is_delete = 0;
 898                         patch->new_name = name;
 899                 } else if (has_epoch_timestamp(second)) {
 900                         patch->is_new = 0;
 901                         patch->is_delete = 1;
 902                         patch->old_name = name;
 903                 } else {
 904                         patch->old_name = name;
 905                         patch->new_name = xstrdup_or_null(name);
 906                 }
 907         }
 908         if (!name)
 909                 return error(_("unable to find filename in patch at line %d"), state->linenr);
 910
 911         return 0;
 912 }
 913
 914 static int gitdiff_hdrend(struct apply_state *state,
 915                           const char *line,
 916                           struct patch *patch)
 917 {
 918         return 1;
 919 }
 920
 921 /*
 922  * We're anal about diff header consistency, to make
 923  * sure that we don't end up having strange ambiguous
 924  * patches floating around.
 925  *
 926  * As a result, gitdiff_{old|new}name() will check
 927  * their names against any previous information, just
 928  * to make sure..
 929  */
 930 #define DIFF_OLD_NAME 0
 931 #define DIFF_NEW_NAME 1
 932
 933 static int gitdiff_verify_name(struct apply_state *state,
 934                                const char *line,
 935                                int isnull,
 936                                char **name,
 937                                int side)
 938 {
 939         if (!*name && !isnull) {
 940                 *name = find_name(state, line, NULL, state->p_value, TERM_TAB);
 941                 return 0;
 942         }
 943
 944         if (*name) {
 945                 char *another;
 946                 if (isnull)
 947                         return error(_("git apply: bad git-diff - expected /dev/null, got %s on line %d"),
 948                                      *name, state->linenr);
 949                 another = find_name(state, line, NULL, state->p_value, TERM_TAB);
 950                 if (!another || strcmp(another, *name)) {
 951                         free(another);
 952                         return error((side == DIFF_NEW_NAME) ?
 953                             _("git apply: bad git-diff - inconsistent new filename on line %d") :
 954                             _("git apply: bad git-diff - inconsistent old filename on line %d"), state->linenr);
 955                 }
 956                 free(another);
 957         } else {
 958                 if (!starts_with(line, "/dev/null\n"))
 959                         return error(_("git apply: bad git-diff - expected /dev/null on line %d"), state->linenr);
 960         }
 961
 962         return 0;
 963 }
 964
 965 static int gitdiff_oldname(struct apply_state *state,
 966                            const char *line,
 967                            struct patch *patch)
 968 {
 969         return gitdiff_verify_name(state, line,
 970                                    patch->is_new, &patch->old_name,
 971                                    DIFF_OLD_NAME);
 972 }
 973
 974 static int gitdiff_newname(struct apply_state *state,
 975                            const char *line,
 976                            struct patch *patch)
 977 {
 978         return gitdiff_verify_name(state, line,
 979                                    patch->is_delete, &patch->new_name,
 980                                    DIFF_NEW_NAME);
 981 }
 982
 983 static int parse_mode_line(const char *line, int linenr, unsigned int *mode)
 984 {
 985         char *end;
 986         *mode = strtoul(line, &end, 8);
 987         if (end == line || !isspace(*end))
 988                 return error(_("invalid mode on line %d: %s"), linenr, line);
 989         return 0;
 990 }
 991
 992 static int gitdiff_oldmode(struct apply_state *state,
 993                            const char *line,
 994                            struct patch *patch)
 995 {
 996         return parse_mode_line(line, state->linenr, &patch->old_mode);
 997 }
 998
 999 static int gitdiff_newmode(struct apply_state *state,
1000                            const char *line,
1001                            struct patch *patch)
1002 {
1003         return parse_mode_line(line, state->linenr, &patch->new_mode);
1004 }
1005
1006 static int gitdiff_delete(struct apply_state *state,
1007                           const char *line,
1008                           struct patch *patch)
1009 {
1010         patch->is_delete = 1;
1011         free(patch->old_name);
1012         patch->old_name = xstrdup_or_null(patch->def_name);
1013         return gitdiff_oldmode(state, line, patch);
1014 }
1015
1016 static int gitdiff_newfile(struct apply_state *state,
1017                            const char *line,
1018                            struct patch *patch)
1019 {
1020         patch->is_new = 1;
1021         free(patch->new_name);
1022         patch->new_name = xstrdup_or_null(patch->def_name);
1023         return gitdiff_newmode(state, line, patch);
1024 }
1025
1026 static int gitdiff_copysrc(struct apply_state *state,
1027                            const char *line,
1028                            struct patch *patch)
1029 {
1030         patch->is_copy = 1;
1031         free(patch->old_name);
1032         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1033         return 0;
1034 }
1035
1036 static int gitdiff_copydst(struct apply_state *state,
1037                            const char *line,
1038                            struct patch *patch)
1039 {
1040         patch->is_copy = 1;
1041         free(patch->new_name);
1042         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1043         return 0;
1044 }
1045
1046 static int gitdiff_renamesrc(struct apply_state *state,
1047                              const char *line,
1048                              struct patch *patch)
1049 {
1050         patch->is_rename = 1;
1051         free(patch->old_name);
1052         patch->old_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1053         return 0;
1054 }
1055
1056 static int gitdiff_renamedst(struct apply_state *state,
1057                              const char *line,
1058                              struct patch *patch)
1059 {
1060         patch->is_rename = 1;
1061         free(patch->new_name);
1062         patch->new_name = find_name(state, line, NULL, state->p_value ? state->p_value - 1 : 0, 0);
1063         return 0;
1064 }
1065
1066 static int gitdiff_similarity(struct apply_state *state,
1067                               const char *line,
1068                               struct patch *patch)
1069 {
1070         unsigned long val = strtoul(line, NULL, 10);
1071         if (val <= 100)
1072                 patch->score = val;
1073         return 0;
1074 }
1075
1076 static int gitdiff_dissimilarity(struct apply_state *state,
1077                                  const char *line,
1078                                  struct patch *patch)
1079 {
1080         unsigned long val = strtoul(line, NULL, 10);
1081         if (val <= 100)
1082                 patch->score = val;
1083         return 0;
1084 }
1085
1086 static int gitdiff_index(struct apply_state *state,
1087                          const char *line,
1088                          struct patch *patch)
1089 {
1090         /*
1091          * index line is N hexadecimal, "..", N hexadecimal,
1092          * and optional space with octal mode.
1093          */
1094         const char *ptr, *eol;
1095         int len;
1096
1097         ptr = strchr(line, '.');
1098         if (!ptr || ptr[1] != '.' || 40 < ptr - line)
1099                 return 0;
1100         len = ptr - line;
1101         memcpy(patch->old_sha1_prefix, line, len);
1102         patch->old_sha1_prefix[len] = 0;
1103
1104         line = ptr + 2;
1105         ptr = strchr(line, ' ');
1106         eol = strchrnul(line, '\n');
1107
1108         if (!ptr || eol < ptr)
1109                 ptr = eol;
1110         len = ptr - line;
1111
1112         if (40 < len)
1113                 return 0;
1114         memcpy(patch->new_sha1_prefix, line, len);
1115         patch->new_sha1_prefix[len] = 0;
1116         if (*ptr == ' ')
1117                 return gitdiff_oldmode(state, ptr + 1, patch);
1118         return 0;
1119 }
1120
1121 /*
1122  * This is normal for a diff that doesn't change anything: we'll fall through
1123  * into the next diff. Tell the parser to break out.
1124  */
1125 static int gitdiff_unrecognized(struct apply_state *state,
1126                                 const char *line,
1127                                 struct patch *patch)
1128 {
1129         return 1;
1130 }
1131
1132 /*
1133  * Skip p_value leading components from "line"; as we do not accept
1134  * absolute paths, return NULL in that case.
1135  */
1136 static const char *skip_tree_prefix(struct apply_state *state,
1137                                     const char *line,
1138                                     int llen)
1139 {
1140         int nslash;
1141         int i;
1142
1143         if (!state->p_value)
1144                 return (llen && line[0] == '/') ? NULL : line;
1145
1146         nslash = state->p_value;
1147         for (i = 0; i < llen; i++) {
1148                 int ch = line[i];
1149                 if (ch == '/' && --nslash <= 0)
1150                         return (i == 0) ? NULL : &line[i + 1];
1151         }
1152         return NULL;
1153 }
1154
1155 /*
1156  * This is to extract the same name that appears on "diff --git"
1157  * line.  We do not find and return anything if it is a rename
1158  * patch, and it is OK because we will find the name elsewhere.
1159  * We need to reliably find name only when it is mode-change only,
1160  * creation or deletion of an empty file.  In any of these cases,
1161  * both sides are the same name under a/ and b/ respectively.
1162  */
1163 static char *git_header_name(struct apply_state *state,
1164                              const char *line,
1165                              int llen)
1166 {
1167         const char *name;
1168         const char *second = NULL;
1169         size_t len, line_len;
1170
1171         line += strlen("diff --git ");
1172         llen -= strlen("diff --git ");
1173
1174         if (*line == '"') {
1175                 const char *cp;
1176                 struct strbuf first = STRBUF_INIT;
1177                 struct strbuf sp = STRBUF_INIT;
1178
1179                 if (unquote_c_style(&first, line, &second))
1180                         goto free_and_fail1;
1181
1182                 /* strip the a/b prefix including trailing slash */
1183                 cp = skip_tree_prefix(state, first.buf, first.len);
1184                 if (!cp)
1185                         goto free_and_fail1;
1186                 strbuf_remove(&first, 0, cp - first.buf);
1187
1188                 /*
1189                  * second points at one past closing dq of name.
1190                  * find the second name.
1191                  */
1192                 while ((second < line + llen) && isspace(*second))
1193                         second++;
1194
1195                 if (line + llen <= second)
1196                         goto free_and_fail1;
1197                 if (*second == '"') {
1198                         if (unquote_c_style(&sp, second, NULL))
1199                                 goto free_and_fail1;
1200                         cp = skip_tree_prefix(state, sp.buf, sp.len);
1201                         if (!cp)
1202                                 goto free_and_fail1;
1203                         /* They must match, otherwise ignore */
1204                         if (strcmp(cp, first.buf))
1205                                 goto free_and_fail1;
1206                         strbuf_release(&sp);
1207                         return strbuf_detach(&first, NULL);
1208                 }
1209
1210                 /* unquoted second */
1211                 cp = skip_tree_prefix(state, second, line + llen - second);
1212                 if (!cp)
1213                         goto free_and_fail1;
1214                 if (line + llen - cp != first.len ||
1215                     memcmp(first.buf, cp, first.len))
1216                         goto free_and_fail1;
1217                 return strbuf_detach(&first, NULL);
1218
1219         free_and_fail1:
1220                 strbuf_release(&first);
1221                 strbuf_release(&sp);
1222                 return NULL;
1223         }
1224
1225         /* unquoted first name */
1226         name = skip_tree_prefix(state, line, llen);
1227         if (!name)
1228                 return NULL;
1229
1230         /*
1231          * since the first name is unquoted, a dq if exists must be
1232          * the beginning of the second name.
1233          */
1234         for (second = name; second < line + llen; second++) {
1235                 if (*second == '"') {
1236                         struct strbuf sp = STRBUF_INIT;
1237                         const char *np;
1238
1239                         if (unquote_c_style(&sp, second, NULL))
1240                                 goto free_and_fail2;
1241
1242                         np = skip_tree_prefix(state, sp.buf, sp.len);
1243                         if (!np)
1244                                 goto free_and_fail2;
1245
1246                         len = sp.buf + sp.len - np;
1247                         if (len < second - name &&
1248                             !strncmp(np, name, len) &&
1249                             isspace(name[len])) {
1250                                 /* Good */
1251                                 strbuf_remove(&sp, 0, np - sp.buf);
1252                                 return strbuf_detach(&sp, NULL);
1253                         }
1254
1255                 free_and_fail2:
1256                         strbuf_release(&sp);
1257                         return NULL;
1258                 }
1259         }
1260
1261         /*
1262          * Accept a name only if it shows up twice, exactly the same
1263          * form.
1264          */
1265         second = strchr(name, '\n');
1266         if (!second)
1267                 return NULL;
1268         line_len = second - name;
1269         for (len = 0 ; ; len++) {
1270                 switch (name[len]) {
1271                 default:
1272                         continue;
1273                 case '\n':
1274                         return NULL;
1275                 case '\t': case ' ':
1276                         /*
1277                          * Is this the separator between the preimage
1278                          * and the postimage pathname?  Again, we are
1279                          * only interested in the case where there is
1280                          * no rename, as this is only to set def_name
1281                          * and a rename patch has the names elsewhere
1282                          * in an unambiguous form.
1283                          */
1284                         if (!name[len + 1])
1285                                 return NULL; /* no postimage name */
1286                         second = skip_tree_prefix(state, name + len + 1,
1287                                                   line_len - (len + 1));
1288                         if (!second)
1289                                 return NULL;
1290                         /*
1291                          * Does len bytes starting at "name" and "second"
1292                          * (that are separated by one HT or SP we just
1293                          * found) exactly match?
1294                          */
1295                         if (second[len] == '\n' && !strncmp(name, second, len))
1296                                 return xmemdupz(name, len);
1297                 }
1298         }
1299 }
1300
1301 static int check_header_line(struct apply_state *state, struct patch *patch)
1302 {
1303         int extensions = (patch->is_delete == 1) + (patch->is_new == 1) +
1304                          (patch->is_rename == 1) + (patch->is_copy == 1);
1305         if (extensions > 1)
1306                 return error(_("inconsistent header lines %d and %d"),
1307                              patch->extension_linenr, state->linenr);
1308         if (extensions && !patch->extension_linenr)
1309                 patch->extension_linenr = state->linenr;
1310         return 0;
1311 }
1312
1313 /* Verify that we recognize the lines following a git header */
1314 static int parse_git_header(struct apply_state *state,
1315                             const char *line,
1316                             int len,
1317                             unsigned int size,
1318                             struct patch *patch)
1319 {
1320         unsigned long offset;
1321
1322         /* A git diff has explicit new/delete information, so we don't guess */
1323         patch->is_new = 0;
1324         patch->is_delete = 0;
1325
1326         /*
1327          * Some things may not have the old name in the
1328          * rest of the headers anywhere (pure mode changes,
1329          * or removing or adding empty files), so we get
1330          * the default name from the header.
1331          */
1332         patch->def_name = git_header_name(state, line, len);
1333         if (patch->def_name && state->root.len) {
1334                 char *s = xstrfmt("%s%s", state->root.buf, patch->def_name);
1335                 free(patch->def_name);
1336                 patch->def_name = s;
1337         }
1338
1339         line += len;
1340         size -= len;
1341         state->linenr++;
1342         for (offset = len ; size > 0 ; offset += len, size -= len, line += len, state->linenr++) {
1343                 static const struct opentry {
1344                         const char *str;
1345                         int (*fn)(struct apply_state *, const char *, struct patch *);
1346                 } optable[] = {
1347                         { "@@ -", gitdiff_hdrend },
1348                         { "--- ", gitdiff_oldname },
1349                         { "+++ ", gitdiff_newname },
1350                         { "old mode ", gitdiff_oldmode },
1351                         { "new mode ", gitdiff_newmode },
1352                         { "deleted file mode ", gitdiff_delete },
1353                         { "new file mode ", gitdiff_newfile },
1354                         { "copy from ", gitdiff_copysrc },
1355                         { "copy to ", gitdiff_copydst },
1356                         { "rename old ", gitdiff_renamesrc },
1357                         { "rename new ", gitdiff_renamedst },
1358                         { "rename from ", gitdiff_renamesrc },
1359                         { "rename to ", gitdiff_renamedst },
1360                         { "similarity index ", gitdiff_similarity },
1361                         { "dissimilarity index ", gitdiff_dissimilarity },
1362                         { "index ", gitdiff_index },
1363                         { "", gitdiff_unrecognized },
1364                 };
1365                 int i;
1366
1367                 len = linelen(line, size);
1368                 if (!len || line[len-1] != '\n')
1369                         break;
1370                 for (i = 0; i < ARRAY_SIZE(optable); i++) {
1371                         const struct opentry *p = optable + i;
1372                         int oplen = strlen(p->str);
1373                         int res;
1374                         if (len < oplen || memcmp(p->str, line, oplen))
1375                                 continue;
1376                         res = p->fn(state, line + oplen, patch);
1377                         if (res < 0)
1378                                 return -1;
1379                         if (check_header_line(state, patch))
1380                                 return -1;
1381                         if (res > 0)
1382                                 return offset;
1383                         break;
1384                 }
1385         }
1386
1387         return offset;
1388 }
1389
1390 static int parse_num(const char *line, unsigned long *p)
1391 {
1392         char *ptr;
1393
1394         if (!isdigit(*line))
1395                 return 0;
1396         *p = strtoul(line, &ptr, 10);
1397         return ptr - line;
1398 }
1399
1400 static int parse_range(const char *line, int len, int offset, const char *expect,
1401                        unsigned long *p1, unsigned long *p2)
1402 {
1403         int digits, ex;
1404
1405         if (offset < 0 || offset >= len)
1406                 return -1;
1407         line += offset;
1408         len -= offset;
1409
1410         digits = parse_num(line, p1);
1411         if (!digits)
1412                 return -1;
1413
1414         offset += digits;
1415         line += digits;
1416         len -= digits;
1417
1418         *p2 = 1;
1419         if (*line == ',') {
1420                 digits = parse_num(line+1, p2);
1421                 if (!digits)
1422                         return -1;
1423
1424                 offset += digits+1;
1425                 line += digits+1;
1426                 len -= digits+1;
1427         }
1428
1429         ex = strlen(expect);
1430         if (ex > len)
1431                 return -1;
1432         if (memcmp(line, expect, ex))
1433                 return -1;
1434
1435         return offset + ex;
1436 }
1437
1438 static void recount_diff(const char *line, int size, struct fragment *fragment)
1439 {
1440         int oldlines = 0, newlines = 0, ret = 0;
1441
1442         if (size < 1) {
1443                 warning("recount: ignore empty hunk");
1444                 return;
1445         }
1446
1447         for (;;) {
1448                 int len = linelen(line, size);
1449                 size -= len;
1450                 line += len;
1451
1452                 if (size < 1)
1453                         break;
1454
1455                 switch (*line) {
1456                 case ' ': case '\n':
1457                         newlines++;
1458                         /* fall through */
1459                 case '-':
1460                         oldlines++;
1461                         continue;
1462                 case '+':
1463                         newlines++;
1464                         continue;
1465                 case '\\':
1466                         continue;
1467                 case '@':
1468                         ret = size < 3 || !starts_with(line, "@@ ");
1469                         break;
1470                 case 'd':
1471                         ret = size < 5 || !starts_with(line, "diff ");
1472                         break;
1473                 default:
1474                         ret = -1;
1475                         break;
1476                 }
1477                 if (ret) {
1478                         warning(_("recount: unexpected line: %.*s"),
1479                                 (int)linelen(line, size), line);
1480                         return;
1481                 }
1482                 break;
1483         }
1484         fragment->oldlines = oldlines;
1485         fragment->newlines = newlines;
1486 }
1487
1488 /*
1489  * Parse a unified diff fragment header of the
1490  * form "@@ -a,b +c,d @@"
1491  */
1492 static int parse_fragment_header(const char *line, int len, struct fragment *fragment)
1493 {
1494         int offset;
1495
1496         if (!len || line[len-1] != '\n')
1497                 return -1;
1498
1499         /* Figure out the number of lines in a fragment */
1500         offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
1501         offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
1502
1503         return offset;
1504 }
1505
1506 /*
1507  * Find file diff header
1508  *
1509  * Returns:
1510  *  -1 if no header was found
1511  *  -128 in case of error
1512  *   the size of the header in bytes (called "offset") otherwise
1513  */
1514 static int find_header(struct apply_state *state,
1515                        const char *line,
1516                        unsigned long size,
1517                        int *hdrsize,
1518                        struct patch *patch)
1519 {
1520         unsigned long offset, len;
1521
1522         patch->is_toplevel_relative = 0;
1523         patch->is_rename = patch->is_copy = 0;
1524         patch->is_new = patch->is_delete = -1;
1525         patch->old_mode = patch->new_mode = 0;
1526         patch->old_name = patch->new_name = NULL;
1527         for (offset = 0; size > 0; offset += len, size -= len, line += len, state->linenr++) {
1528                 unsigned long nextlen;
1529
1530                 len = linelen(line, size);
1531                 if (!len)
1532                         break;
1533
1534                 /* Testing this early allows us to take a few shortcuts.. */
1535                 if (len < 6)
1536                         continue;
1537
1538                 /*
1539                  * Make sure we don't find any unconnected patch fragments.
1540                  * That's a sign that we didn't find a header, and that a
1541                  * patch has become corrupted/broken up.
1542                  */
1543                 if (!memcmp("@@ -", line, 4)) {
1544                         struct fragment dummy;
1545                         if (parse_fragment_header(line, len, &dummy) < 0)
1546                                 continue;
1547                         error(_("patch fragment without header at line %d: %.*s"),
1548                                      state->linenr, (int)len-1, line);
1549                         return -128;
1550                 }
1551
1552                 if (size < len + 6)
1553                         break;
1554
1555                 /*
1556                  * Git patch? It might not have a real patch, just a rename
1557                  * or mode change, so we handle that specially
1558                  */
1559                 if (!memcmp("diff --git ", line, 11)) {
1560                         int git_hdr_len = parse_git_header(state, line, len, size, patch);
1561                         if (git_hdr_len < 0)
1562                                 return -128;
1563                         if (git_hdr_len <= len)
1564                                 continue;
1565                         if (!patch->old_name && !patch->new_name) {
1566                                 if (!patch->def_name) {
1567                                         error(Q_("git diff header lacks filename information when removing "
1568                                                         "%d leading pathname component (line %d)",
1569                                                         "git diff header lacks filename information when removing "
1570                                                         "%d leading pathname components (line %d)",
1571                                                         state->p_value),
1572                                                      state->p_value, state->linenr);
1573                                         return -128;
1574                                 }
1575                                 patch->old_name = xstrdup(patch->def_name);
1576                                 patch->new_name = xstrdup(patch->def_name);
1577                         }
1578                         if ((!patch->new_name && !patch->is_delete) ||
1579                             (!patch->old_name && !patch->is_new)) {
1580                                 error(_("git diff header lacks filename information "
1581                                              "(line %d)"), state->linenr);
1582                                 return -128;
1583                         }
1584                         patch->is_toplevel_relative = 1;
1585                         *hdrsize = git_hdr_len;
1586                         return offset;
1587                 }
1588
1589                 /* --- followed by +++ ? */
1590                 if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
1591                         continue;
1592
1593                 /*
1594                  * We only accept unified patches, so we want it to
1595                  * at least have "@@ -a,b +c,d @@\n", which is 14 chars
1596                  * minimum ("@@ -0,0 +1 @@\n" is the shortest).
1597                  */
1598                 nextlen = linelen(line + len, size - len);
1599                 if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
1600                         continue;
1601
1602                 /* Ok, we'll consider it a patch */
1603                 if (parse_traditional_patch(state, line, line+len, patch))
1604                         return -128;
1605                 *hdrsize = len + nextlen;
1606                 state->linenr += 2;
1607                 return offset;
1608         }
1609         return -1;
1610 }
1611
1612 static void record_ws_error(struct apply_state *state,
1613                             unsigned result,
1614                             const char *line,
1615                             int len,
1616                             int linenr)
1617 {
1618         char *err;
1619
1620         if (!result)
1621                 return;
1622
1623         state->whitespace_error++;
1624         if (state->squelch_whitespace_errors &&
1625             state->squelch_whitespace_errors < state->whitespace_error)
1626                 return;
1627
1628         err = whitespace_error_string(result);
1629         if (state->apply_verbosity > verbosity_silent)
1630                 fprintf(stderr, "%s:%d: %s.\n%.*s\n",
1631                         state->patch_input_file, linenr, err, len, line);
1632         free(err);
1633 }
1634
1635 static void check_whitespace(struct apply_state *state,
1636                              const char *line,
1637                              int len,
1638                              unsigned ws_rule)
1639 {
1640         unsigned result = ws_check(line + 1, len - 1, ws_rule);
1641
1642         record_ws_error(state, result, line + 1, len - 2, state->linenr);
1643 }
1644
1645 /*
1646  * Check if the patch has context lines with CRLF or
1647  * the patch wants to remove lines with CRLF.
1648  */
1649 static void check_old_for_crlf(struct patch *patch, const char *line, int len)
1650 {
1651         if (len >= 2 && line[len-1] == '\n' && line[len-2] == '\r') {
1652                 patch->ws_rule |= WS_CR_AT_EOL;
1653                 patch->crlf_in_old = 1;
1654         }
1655 }
1656
1657
1658 /*
1659  * Parse a unified diff. Note that this really needs to parse each
1660  * fragment separately, since the only way to know the difference
1661  * between a "---" that is part of a patch, and a "---" that starts
1662  * the next patch is to look at the line counts..
1663  */
1664 static int parse_fragment(struct apply_state *state,
1665                           const char *line,
1666                           unsigned long size,
1667                           struct patch *patch,
1668                           struct fragment *fragment)
1669 {
1670         int added, deleted;
1671         int len = linelen(line, size), offset;
1672         unsigned long oldlines, newlines;
1673         unsigned long leading, trailing;
1674
1675         offset = parse_fragment_header(line, len, fragment);
1676         if (offset < 0)
1677                 return -1;
1678         if (offset > 0 && patch->recount)
1679                 recount_diff(line + offset, size - offset, fragment);
1680         oldlines = fragment->oldlines;
1681         newlines = fragment->newlines;
1682         leading = 0;
1683         trailing = 0;
1684
1685         /* Parse the thing.. */
1686         line += len;
1687         size -= len;
1688         state->linenr++;
1689         added = deleted = 0;
1690         for (offset = len;
1691              0 < size;
1692              offset += len, size -= len, line += len, state->linenr++) {
1693                 if (!oldlines && !newlines)
1694                         break;
1695                 len = linelen(line, size);
1696                 if (!len || line[len-1] != '\n')
1697                         return -1;
1698                 switch (*line) {
1699                 default:
1700                         return -1;
1701                 case '\n': /* newer GNU diff, an empty context line */
1702                 case ' ':
1703                         oldlines--;
1704                         newlines--;
1705                         if (!deleted && !added)
1706                                 leading++;
1707                         trailing++;
1708                         check_old_for_crlf(patch, line, len);
1709                         if (!state->apply_in_reverse &&
1710                             state->ws_error_action == correct_ws_error)
1711                                 check_whitespace(state, line, len, patch->ws_rule);
1712                         break;
1713                 case '-':
1714                         if (!state->apply_in_reverse)
1715                                 check_old_for_crlf(patch, line, len);
1716                         if (state->apply_in_reverse &&
1717                             state->ws_error_action != nowarn_ws_error)
1718                                 check_whitespace(state, line, len, patch->ws_rule);
1719                         deleted++;
1720                         oldlines--;
1721                         trailing = 0;
1722                         break;
1723                 case '+':
1724                         if (state->apply_in_reverse)
1725                                 check_old_for_crlf(patch, line, len);
1726                         if (!state->apply_in_reverse &&
1727                             state->ws_error_action != nowarn_ws_error)
1728                                 check_whitespace(state, line, len, patch->ws_rule);
1729                         added++;
1730                         newlines--;
1731                         trailing = 0;
1732                         break;
1733
1734                 /*
1735                  * We allow "\ No newline at end of file". Depending
1736                  * on locale settings when the patch was produced we
1737                  * don't know what this line looks like. The only
1738                  * thing we do know is that it begins with "\ ".
1739                  * Checking for 12 is just for sanity check -- any
1740                  * l10n of "\ No newline..." is at least that long.
1741                  */
1742                 case '\\':
1743                         if (len < 12 || memcmp(line, "\\ ", 2))
1744                                 return -1;
1745                         break;
1746                 }
1747         }
1748         if (oldlines || newlines)
1749                 return -1;
1750         if (!deleted && !added)
1751                 return -1;
1752
1753         fragment->leading = leading;
1754         fragment->trailing = trailing;
1755
1756         /*
1757          * If a fragment ends with an incomplete line, we failed to include
1758          * it in the above loop because we hit oldlines == newlines == 0
1759          * before seeing it.
1760          */
1761         if (12 < size && !memcmp(line, "\\ ", 2))
1762                 offset += linelen(line, size);
1763
1764         patch->lines_added += added;
1765         patch->lines_deleted += deleted;
1766
1767         if (0 < patch->is_new && oldlines)
1768                 return error(_("new file depends on old contents"));
1769         if (0 < patch->is_delete && newlines)
1770                 return error(_("deleted file still has contents"));
1771         return offset;
1772 }
1773
1774 /*
1775  * We have seen "diff --git a/... b/..." header (or a traditional patch
1776  * header).  Read hunks that belong to this patch into fragments and hang
1777  * them to the given patch structure.
1778  *
1779  * The (fragment->patch, fragment->size) pair points into the memory given
1780  * by the caller, not a copy, when we return.
1781  *
1782  * Returns:
1783  *   -1 in case of error,
1784  *   the number of bytes in the patch otherwise.
1785  */
1786 static int parse_single_patch(struct apply_state *state,
1787                               const char *line,
1788                               unsigned long size,
1789                               struct patch *patch)
1790 {
1791         unsigned long offset = 0;
1792         unsigned long oldlines = 0, newlines = 0, context = 0;
1793         struct fragment **fragp = &patch->fragments;
1794
1795         while (size > 4 && !memcmp(line, "@@ -", 4)) {
1796                 struct fragment *fragment;
1797                 int len;
1798
1799                 fragment = xcalloc(1, sizeof(*fragment));
1800                 fragment->linenr = state->linenr;
1801                 len = parse_fragment(state, line, size, patch, fragment);
1802                 if (len <= 0) {
1803                         free(fragment);
1804                         return error(_("corrupt patch at line %d"), state->linenr);
1805                 }
1806                 fragment->patch = line;
1807                 fragment->size = len;
1808                 oldlines += fragment->oldlines;
1809                 newlines += fragment->newlines;
1810                 context += fragment->leading + fragment->trailing;
1811
1812                 *fragp = fragment;
1813                 fragp = &fragment->next;
1814
1815                 offset += len;
1816                 line += len;
1817                 size -= len;
1818         }
1819
1820         /*
1821          * If something was removed (i.e. we have old-lines) it cannot
1822          * be creation, and if something was added it cannot be
1823          * deletion.  However, the reverse is not true; --unified=0
1824          * patches that only add are not necessarily creation even
1825          * though they do not have any old lines, and ones that only
1826          * delete are not necessarily deletion.
1827          *
1828          * Unfortunately, a real creation/deletion patch do _not_ have
1829          * any context line by definition, so we cannot safely tell it
1830          * apart with --unified=0 insanity.  At least if the patch has
1831          * more than one hunk it is not creation or deletion.
1832          */
1833         if (patch->is_new < 0 &&
1834             (oldlines || (patch->fragments && patch->fragments->next)))
1835                 patch->is_new = 0;
1836         if (patch->is_delete < 0 &&
1837             (newlines || (patch->fragments && patch->fragments->next)))
1838                 patch->is_delete = 0;
1839
1840         if (0 < patch->is_new && oldlines)
1841                 return error(_("new file %s depends on old contents"), patch->new_name);
1842         if (0 < patch->is_delete && newlines)
1843                 return error(_("deleted file %s still has contents"), patch->old_name);
1844         if (!patch->is_delete && !newlines && context && state->apply_verbosity > verbosity_silent)
1845                 fprintf_ln(stderr,
1846                            _("** warning: "
1847                              "file %s becomes empty but is not deleted"),
1848                            patch->new_name);
1849
1850         return offset;
1851 }
1852
1853 static inline int metadata_changes(struct patch *patch)
1854 {
1855         return  patch->is_rename > 0 ||
1856                 patch->is_copy > 0 ||
1857                 patch->is_new > 0 ||
1858                 patch->is_delete ||
1859                 (patch->old_mode && patch->new_mode &&
1860                  patch->old_mode != patch->new_mode);
1861 }
1862
1863 static char *inflate_it(const void *data, unsigned long size,
1864                         unsigned long inflated_size)
1865 {
1866         git_zstream stream;
1867         void *out;
1868         int st;
1869
1870         memset(&stream, 0, sizeof(stream));
1871
1872         stream.next_in = (unsigned char *)data;
1873         stream.avail_in = size;
1874         stream.next_out = out = xmalloc(inflated_size);
1875         stream.avail_out = inflated_size;
1876         git_inflate_init(&stream);
1877         st = git_inflate(&stream, Z_FINISH);
1878         git_inflate_end(&stream);
1879         if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
1880                 free(out);
1881                 return NULL;
1882         }
1883         return out;
1884 }
1885
1886 /*
1887  * Read a binary hunk and return a new fragment; fragment->patch
1888  * points at an allocated memory that the caller must free, so
1889  * it is marked as "->free_patch = 1".
1890  */
1891 static struct fragment *parse_binary_hunk(struct apply_state *state,
1892                                           char **buf_p,
1893                                           unsigned long *sz_p,
1894                                           int *status_p,
1895                                           int *used_p)
1896 {
1897         /*
1898          * Expect a line that begins with binary patch method ("literal"
1899          * or "delta"), followed by the length of data before deflating.
1900          * a sequence of 'length-byte' followed by base-85 encoded data
1901          * should follow, terminated by a newline.
1902          *
1903          * Each 5-byte sequence of base-85 encodes up to 4 bytes,
1904          * and we would limit the patch line to 66 characters,
1905          * so one line can fit up to 13 groups that would decode
1906          * to 52 bytes max.  The length byte 'A'-'Z' corresponds
1907          * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
1908          */
1909         int llen, used;
1910         unsigned long size = *sz_p;
1911         char *buffer = *buf_p;
1912         int patch_method;
1913         unsigned long origlen;
1914         char *data = NULL;
1915         int hunk_size = 0;
1916         struct fragment *frag;
1917
1918         llen = linelen(buffer, size);
1919         used = llen;
1920
1921         *status_p = 0;
1922
1923         if (starts_with(buffer, "delta ")) {
1924                 patch_method = BINARY_DELTA_DEFLATED;
1925                 origlen = strtoul(buffer + 6, NULL, 10);
1926         }
1927         else if (starts_with(buffer, "literal ")) {
1928                 patch_method = BINARY_LITERAL_DEFLATED;
1929                 origlen = strtoul(buffer + 8, NULL, 10);
1930         }
1931         else
1932                 return NULL;
1933
1934         state->linenr++;
1935         buffer += llen;
1936         while (1) {
1937                 int byte_length, max_byte_length, newsize;
1938                 llen = linelen(buffer, size);
1939                 used += llen;
1940                 state->linenr++;
1941                 if (llen == 1) {
1942                         /* consume the blank line */
1943                         buffer++;
1944                         size--;
1945                         break;
1946                 }
1947                 /*
1948                  * Minimum line is "A00000\n" which is 7-byte long,
1949                  * and the line length must be multiple of 5 plus 2.
1950                  */
1951                 if ((llen < 7) || (llen-2) % 5)
1952                         goto corrupt;
1953                 max_byte_length = (llen - 2) / 5 * 4;
1954                 byte_length = *buffer;
1955                 if ('A' <= byte_length && byte_length <= 'Z')
1956                         byte_length = byte_length - 'A' + 1;
1957                 else if ('a' <= byte_length && byte_length <= 'z')
1958                         byte_length = byte_length - 'a' + 27;
1959                 else
1960                         goto corrupt;
1961                 /* if the input length was not multiple of 4, we would
1962                  * have filler at the end but the filler should never
1963                  * exceed 3 bytes
1964                  */
1965                 if (max_byte_length < byte_length ||
1966                     byte_length <= max_byte_length - 4)
1967                         goto corrupt;
1968                 newsize = hunk_size + byte_length;
1969                 data = xrealloc(data, newsize);
1970                 if (decode_85(data + hunk_size, buffer + 1, byte_length))
1971                         goto corrupt;
1972                 hunk_size = newsize;
1973                 buffer += llen;
1974                 size -= llen;
1975         }
1976
1977         frag = xcalloc(1, sizeof(*frag));
1978         frag->patch = inflate_it(data, hunk_size, origlen);
1979         frag->free_patch = 1;
1980         if (!frag->patch)
1981                 goto corrupt;
1982         free(data);
1983         frag->size = origlen;
1984         *buf_p = buffer;
1985         *sz_p = size;
1986         *used_p = used;
1987         frag->binary_patch_method = patch_method;
1988         return frag;
1989
1990  corrupt:
1991         free(data);
1992         *status_p = -1;
1993         error(_("corrupt binary patch at line %d: %.*s"),
1994               state->linenr-1, llen-1, buffer);
1995         return NULL;
1996 }
1997
1998 /*
1999  * Returns:
2000  *   -1 in case of error,
2001  *   the length of the parsed binary patch otherwise
2002  */
2003 static int parse_binary(struct apply_state *state,
2004                         char *buffer,
2005                         unsigned long size,
2006                         struct patch *patch)
2007 {
2008         /*
2009          * We have read "GIT binary patch\n"; what follows is a line
2010          * that says the patch method (currently, either "literal" or
2011          * "delta") and the length of data before deflating; a
2012          * sequence of 'length-byte' followed by base-85 encoded data
2013          * follows.
2014          *
2015          * When a binary patch is reversible, there is another binary
2016          * hunk in the same format, starting with patch method (either
2017          * "literal" or "delta") with the length of data, and a sequence
2018          * of length-byte + base-85 encoded data, terminated with another
2019          * empty line.  This data, when applied to the postimage, produces
2020          * the preimage.
2021          */
2022         struct fragment *forward;
2023         struct fragment *reverse;
2024         int status;
2025         int used, used_1;
2026
2027         forward = parse_binary_hunk(state, &buffer, &size, &status, &used);
2028         if (!forward && !status)
2029                 /* there has to be one hunk (forward hunk) */
2030                 return error(_("unrecognized binary patch at line %d"), state->linenr-1);
2031         if (status)
2032                 /* otherwise we already gave an error message */
2033                 return status;
2034
2035         reverse = parse_binary_hunk(state, &buffer, &size, &status, &used_1);
2036         if (reverse)
2037                 used += used_1;
2038         else if (status) {
2039                 /*
2040                  * Not having reverse hunk is not an error, but having
2041                  * a corrupt reverse hunk is.
2042                  */
2043                 free((void*) forward->patch);
2044                 free(forward);
2045                 return status;
2046         }
2047         forward->next = reverse;
2048         patch->fragments = forward;
2049         patch->is_binary = 1;
2050         return used;
2051 }
2052
2053 static void prefix_one(struct apply_state *state, char **name)
2054 {
2055         char *old_name = *name;
2056         if (!old_name)
2057                 return;
2058         *name = prefix_filename(state->prefix, *name);
2059         free(old_name);
2060 }
2061
2062 static void prefix_patch(struct apply_state *state, struct patch *p)
2063 {
2064         if (!state->prefix || p->is_toplevel_relative)
2065                 return;
2066         prefix_one(state, &p->new_name);
2067         prefix_one(state, &p->old_name);
2068 }
2069
2070 /*
2071  * include/exclude
2072  */
2073
2074 static void add_name_limit(struct apply_state *state,
2075                            const char *name,
2076                            int exclude)
2077 {
2078         struct string_list_item *it;
2079
2080         it = string_list_append(&state->limit_by_name, name);
2081         it->util = exclude ? NULL : (void *) 1;
2082 }
2083
2084 static int use_patch(struct apply_state *state, struct patch *p)
2085 {
2086         const char *pathname = p->new_name ? p->new_name : p->old_name;
2087         int i;
2088
2089         /* Paths outside are not touched regardless of "--include" */
2090         if (state->prefix && *state->prefix) {
2091                 const char *rest;
2092                 if (!skip_prefix(pathname, state->prefix, &rest) || !*rest)
2093                         return 0;
2094         }
2095
2096         /* See if it matches any of exclude/include rule */
2097         for (i = 0; i < state->limit_by_name.nr; i++) {
2098                 struct string_list_item *it = &state->limit_by_name.items[i];
2099                 if (!wildmatch(it->string, pathname, 0))
2100                         return (it->util != NULL);
2101         }
2102
2103         /*
2104          * If we had any include, a path that does not match any rule is
2105          * not used.  Otherwise, we saw bunch of exclude rules (or none)
2106          * and such a path is used.
2107          */
2108         return !state->has_include;
2109 }
2110
2111 /*
2112  * Read the patch text in "buffer" that extends for "size" bytes; stop
2113  * reading after seeing a single patch (i.e. changes to a single file).
2114  * Create fragments (i.e. patch hunks) and hang them to the given patch.
2115  *
2116  * Returns:
2117  *   -1 if no header was found or parse_binary() failed,
2118  *   -128 on another error,
2119  *   the number of bytes consumed otherwise,
2120  *     so that the caller can call us again for the next patch.
2121  */
2122 static int parse_chunk(struct apply_state *state, char *buffer, unsigned long size, struct patch *patch)
2123 {
2124         int hdrsize, patchsize;
2125         int offset = find_header(state, buffer, size, &hdrsize, patch);
2126
2127         if (offset < 0)
2128                 return offset;
2129
2130         prefix_patch(state, patch);
2131
2132         if (!use_patch(state, patch))
2133                 patch->ws_rule = 0;
2134         else
2135                 patch->ws_rule = whitespace_rule(patch->new_name
2136                                                  ? patch->new_name
2137                                                  : patch->old_name);
2138
2139         patchsize = parse_single_patch(state,
2140                                        buffer + offset + hdrsize,
2141                                        size - offset - hdrsize,
2142                                        patch);
2143
2144         if (patchsize < 0)
2145                 return -128;
2146
2147         if (!patchsize) {
2148                 static const char git_binary[] = "GIT binary patch\n";
2149                 int hd = hdrsize + offset;
2150                 unsigned long llen = linelen(buffer + hd, size - hd);
2151
2152                 if (llen == sizeof(git_binary) - 1 &&
2153                     !memcmp(git_binary, buffer + hd, llen)) {
2154                         int used;
2155                         state->linenr++;
2156                         used = parse_binary(state, buffer + hd + llen,
2157                                             size - hd - llen, patch);
2158                         if (used < 0)
2159                                 return -1;
2160                         if (used)
2161                                 patchsize = used + llen;
2162                         else
2163                                 patchsize = 0;
2164                 }
2165                 else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
2166                         static const char *binhdr[] = {
2167                                 "Binary files ",
2168                                 "Files ",
2169                                 NULL,
2170                         };
2171                         int i;
2172                         for (i = 0; binhdr[i]; i++) {
2173                                 int len = strlen(binhdr[i]);
2174                                 if (len < size - hd &&
2175                                     !memcmp(binhdr[i], buffer + hd, len)) {
2176                                         state->linenr++;
2177                                         patch->is_binary = 1;
2178                                         patchsize = llen;
2179                                         break;
2180                                 }
2181                         }
2182                 }
2183
2184                 /* Empty patch cannot be applied if it is a text patch
2185                  * without metadata change.  A binary patch appears
2186                  * empty to us here.
2187                  */
2188                 if ((state->apply || state->check) &&
2189                     (!patch->is_binary && !metadata_changes(patch))) {
2190                         error(_("patch with only garbage at line %d"), state->linenr);
2191                         return -128;
2192                 }
2193         }
2194
2195         return offset + hdrsize + patchsize;
2196 }
2197
2198 static void reverse_patches(struct patch *p)
2199 {
2200         for (; p; p = p->next) {
2201                 struct fragment *frag = p->fragments;
2202
2203                 SWAP(p->new_name, p->old_name);
2204                 SWAP(p->new_mode, p->old_mode);
2205                 SWAP(p->is_new, p->is_delete);
2206                 SWAP(p->lines_added, p->lines_deleted);
2207                 SWAP(p->old_sha1_prefix, p->new_sha1_prefix);
2208
2209                 for (; frag; frag = frag->next) {
2210                         SWAP(frag->newpos, frag->oldpos);
2211                         SWAP(frag->newlines, frag->oldlines);
2212                 }
2213         }
2214 }
2215
2216 static const char pluses[] =
2217 "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
2218 static const char minuses[]=
2219 "----------------------------------------------------------------------";
2220
2221 static void show_stats(struct apply_state *state, struct patch *patch)
2222 {
2223         struct strbuf qname = STRBUF_INIT;
2224         char *cp = patch->new_name ? patch->new_name : patch->old_name;
2225         int max, add, del;
2226
2227         quote_c_style(cp, &qname, NULL, 0);
2228
2229         /*
2230          * "scale" the filename
2231          */
2232         max = state->max_len;
2233         if (max > 50)
2234                 max = 50;
2235
2236         if (qname.len > max) {
2237                 cp = strchr(qname.buf + qname.len + 3 - max, '/');
2238                 if (!cp)
2239                         cp = qname.buf + qname.len + 3 - max;
2240                 strbuf_splice(&qname, 0, cp - qname.buf, "...", 3);
2241         }
2242
2243         if (patch->is_binary) {
2244                 printf(" %-*s |  Bin\n", max, qname.buf);
2245                 strbuf_release(&qname);
2246                 return;
2247         }
2248
2249         printf(" %-*s |", max, qname.buf);
2250         strbuf_release(&qname);
2251
2252         /*
2253          * scale the add/delete
2254          */
2255         max = max + state->max_change > 70 ? 70 - max : state->max_change;
2256         add = patch->lines_added;
2257         del = patch->lines_deleted;
2258
2259         if (state->max_change > 0) {
2260                 int total = ((add + del) * max + state->max_change / 2) / state->max_change;
2261                 add = (add * max + state->max_change / 2) / state->max_change;
2262                 del = total - add;
2263         }
2264         printf("%5d %.*s%.*s\n", patch->lines_added + patch->lines_deleted,
2265                 add, pluses, del, minuses);
2266 }
2267
2268 static int read_old_data(struct stat *st, struct patch *patch,
2269                          const char *path, struct strbuf *buf)
2270 {
2271         enum safe_crlf safe_crlf = patch->crlf_in_old ?
2272                 SAFE_CRLF_KEEP_CRLF : SAFE_CRLF_RENORMALIZE;
2273         switch (st->st_mode & S_IFMT) {
2274         case S_IFLNK:
2275                 if (strbuf_readlink(buf, path, st->st_size) < 0)
2276                         return error(_("unable to read symlink %s"), path);
2277                 return 0;
2278         case S_IFREG:
2279                 if (strbuf_read_file(buf, path, st->st_size) != st->st_size)
2280                         return error(_("unable to open or read %s"), path);
2281                 /*
2282                  * "git apply" without "--index/--cached" should never look
2283                  * at the index; the target file may not have been added to
2284                  * the index yet, and we may not even be in any Git repository.
2285                  * Pass NULL to convert_to_git() to stress this; the function
2286                  * should never look at the index when explicit crlf option
2287                  * is given.
2288                  */
2289                 convert_to_git(NULL, path, buf->buf, buf->len, buf, safe_crlf);
2290                 return 0;
2291         default:
2292                 return -1;
2293         }
2294 }
2295
2296 /*
2297  * Update the preimage, and the common lines in postimage,
2298  * from buffer buf of length len. If postlen is 0 the postimage
2299  * is updated in place, otherwise it's updated on a new buffer
2300  * of length postlen
2301  */
2302
2303 static void update_pre_post_images(struct image *preimage,
2304                                    struct image *postimage,
2305                                    char *buf,
2306                                    size_t len, size_t postlen)
2307 {
2308         int i, ctx, reduced;
2309         char *new, *old, *fixed;
2310         struct image fixed_preimage;
2311
2312         /*
2313          * Update the preimage with whitespace fixes.  Note that we
2314          * are not losing preimage->buf -- apply_one_fragment() will
2315          * free "oldlines".
2316          */
2317         prepare_image(&fixed_preimage, buf, len, 1);
2318         assert(postlen
2319                ? fixed_preimage.nr == preimage->nr
2320                : fixed_preimage.nr <= preimage->nr);
2321         for (i = 0; i < fixed_preimage.nr; i++)
2322                 fixed_preimage.line[i].flag = preimage->line[i].flag;
2323         free(preimage->line_allocated);
2324         *preimage = fixed_preimage;
2325
2326         /*
2327          * Adjust the common context lines in postimage. This can be
2328          * done in-place when we are shrinking it with whitespace
2329          * fixing, but needs a new buffer when ignoring whitespace or
2330          * expanding leading tabs to spaces.
2331          *
2332          * We trust the caller to tell us if the update can be done
2333          * in place (postlen==0) or not.
2334          */
2335         old = postimage->buf;
2336         if (postlen)
2337                 new = postimage->buf = xmalloc(postlen);
2338         else
2339                 new = old;
2340         fixed = preimage->buf;
2341
2342         for (i = reduced = ctx = 0; i < postimage->nr; i++) {
2343                 size_t l_len = postimage->line[i].len;
2344                 if (!(postimage->line[i].flag & LINE_COMMON)) {
2345                         /* an added line -- no counterparts in preimage */
2346                         memmove(new, old, l_len);
2347                         old += l_len;
2348                         new += l_len;
2349                         continue;
2350                 }
2351
2352                 /* a common context -- skip it in the original postimage */
2353                 old += l_len;
2354
2355                 /* and find the corresponding one in the fixed preimage */
2356                 while (ctx < preimage->nr &&
2357                        !(preimage->line[ctx].flag & LINE_COMMON)) {
2358                         fixed += preimage->line[ctx].len;
2359                         ctx++;
2360                 }
2361
2362                 /*
2363                  * preimage is expected to run out, if the caller
2364                  * fixed addition of trailing blank lines.
2365                  */
2366                 if (preimage->nr <= ctx) {
2367                         reduced++;
2368                         continue;
2369                 }
2370
2371                 /* and copy it in, while fixing the line length */
2372                 l_len = preimage->line[ctx].len;
2373                 memcpy(new, fixed, l_len);
2374                 new += l_len;
2375                 fixed += l_len;
2376                 postimage->line[i].len = l_len;
2377                 ctx++;
2378         }
2379
2380         if (postlen
2381             ? postlen < new - postimage->buf
2382             : postimage->len < new - postimage->buf)
2383                 die("BUG: caller miscounted postlen: asked %d, orig = %d, used = %d",
2384                     (int)postlen, (int) postimage->len, (int)(new - postimage->buf));
2385
2386         /* Fix the length of the whole thing */
2387         postimage->len = new - postimage->buf;
2388         postimage->nr -= reduced;
2389 }
2390
2391 static int line_by_line_fuzzy_match(struct image *img,
2392                                     struct image *preimage,
2393                                     struct image *postimage,
2394                                     unsigned long try,
2395                                     int try_lno,
2396                                     int preimage_limit)
2397 {
2398         int i;
2399         size_t imgoff = 0;
2400         size_t preoff = 0;
2401         size_t postlen = postimage->len;
2402         size_t extra_chars;
2403         char *buf;
2404         char *preimage_eof;
2405         char *preimage_end;
2406         struct strbuf fixed;
2407         char *fixed_buf;
2408         size_t fixed_len;
2409
2410         for (i = 0; i < preimage_limit; i++) {
2411                 size_t prelen = preimage->line[i].len;
2412                 size_t imglen = img->line[try_lno+i].len;
2413
2414                 if (!fuzzy_matchlines(img->buf + try + imgoff, imglen,
2415                                       preimage->buf + preoff, prelen))
2416                         return 0;
2417                 if (preimage->line[i].flag & LINE_COMMON)
2418                         postlen += imglen - prelen;
2419                 imgoff += imglen;
2420                 preoff += prelen;
2421         }
2422
2423         /*
2424          * Ok, the preimage matches with whitespace fuzz.
2425          *
2426          * imgoff now holds the true length of the target that
2427          * matches the preimage before the end of the file.
2428          *
2429          * Count the number of characters in the preimage that fall
2430          * beyond the end of the file and make sure that all of them
2431          * are whitespace characters. (This can only happen if
2432          * we are removing blank lines at the end of the file.)
2433          */
2434         buf = preimage_eof = preimage->buf + preoff;
2435         for ( ; i < preimage->nr; i++)
2436                 preoff += preimage->line[i].len;
2437         preimage_end = preimage->buf + preoff;
2438         for ( ; buf < preimage_end; buf++)
2439                 if (!isspace(*buf))
2440                         return 0;
2441
2442         /*
2443          * Update the preimage and the common postimage context
2444          * lines to use the same whitespace as the target.
2445          * If whitespace is missing in the target (i.e.
2446          * if the preimage extends beyond the end of the file),
2447          * use the whitespace from the preimage.
2448          */
2449         extra_chars = preimage_end - preimage_eof;
2450         strbuf_init(&fixed, imgoff + extra_chars);
2451         strbuf_add(&fixed, img->buf + try, imgoff);
2452         strbuf_add(&fixed, preimage_eof, extra_chars);
2453         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2454         update_pre_post_images(preimage, postimage,
2455                                fixed_buf, fixed_len, postlen);
2456         return 1;
2457 }
2458
2459 static int match_fragment(struct apply_state *state,
2460                           struct image *img,
2461                           struct image *preimage,
2462                           struct image *postimage,
2463                           unsigned long try,
2464                           int try_lno,
2465                           unsigned ws_rule,
2466                           int match_beginning, int match_end)
2467 {
2468         int i;
2469         char *fixed_buf, *buf, *orig, *target;
2470         struct strbuf fixed;
2471         size_t fixed_len, postlen;
2472         int preimage_limit;
2473
2474         if (preimage->nr + try_lno <= img->nr) {
2475                 /*
2476                  * The hunk falls within the boundaries of img.
2477                  */
2478                 preimage_limit = preimage->nr;
2479                 if (match_end && (preimage->nr + try_lno != img->nr))
2480                         return 0;
2481         } else if (state->ws_error_action == correct_ws_error &&
2482                    (ws_rule & WS_BLANK_AT_EOF)) {
2483                 /*
2484                  * This hunk extends beyond the end of img, and we are
2485                  * removing blank lines at the end of the file.  This
2486                  * many lines from the beginning of the preimage must
2487                  * match with img, and the remainder of the preimage
2488                  * must be blank.
2489                  */
2490                 preimage_limit = img->nr - try_lno;
2491         } else {
2492                 /*
2493                  * The hunk extends beyond the end of the img and
2494                  * we are not removing blanks at the end, so we
2495                  * should reject the hunk at this position.
2496                  */
2497                 return 0;
2498         }
2499
2500         if (match_beginning && try_lno)
2501                 return 0;
2502
2503         /* Quick hash check */
2504         for (i = 0; i < preimage_limit; i++)
2505                 if ((img->line[try_lno + i].flag & LINE_PATCHED) ||
2506                     (preimage->line[i].hash != img->line[try_lno + i].hash))
2507                         return 0;
2508
2509         if (preimage_limit == preimage->nr) {
2510                 /*
2511                  * Do we have an exact match?  If we were told to match
2512                  * at the end, size must be exactly at try+fragsize,
2513                  * otherwise try+fragsize must be still within the preimage,
2514                  * and either case, the old piece should match the preimage
2515                  * exactly.
2516                  */
2517                 if ((match_end
2518                      ? (try + preimage->len == img->len)
2519                      : (try + preimage->len <= img->len)) &&
2520                     !memcmp(img->buf + try, preimage->buf, preimage->len))
2521                         return 1;
2522         } else {
2523                 /*
2524                  * The preimage extends beyond the end of img, so
2525                  * there cannot be an exact match.
2526                  *
2527                  * There must be one non-blank context line that match
2528                  * a line before the end of img.
2529                  */
2530                 char *buf_end;
2531
2532                 buf = preimage->buf;
2533                 buf_end = buf;
2534                 for (i = 0; i < preimage_limit; i++)
2535                         buf_end += preimage->line[i].len;
2536
2537                 for ( ; buf < buf_end; buf++)
2538                         if (!isspace(*buf))
2539                                 break;
2540                 if (buf == buf_end)
2541                         return 0;
2542         }
2543
2544         /*
2545          * No exact match. If we are ignoring whitespace, run a line-by-line
2546          * fuzzy matching. We collect all the line length information because
2547          * we need it to adjust whitespace if we match.
2548          */
2549         if (state->ws_ignore_action == ignore_ws_change)
2550                 return line_by_line_fuzzy_match(img, preimage, postimage,
2551                                                 try, try_lno, preimage_limit);
2552
2553         if (state->ws_error_action != correct_ws_error)
2554                 return 0;
2555
2556         /*
2557          * The hunk does not apply byte-by-byte, but the hash says
2558          * it might with whitespace fuzz. We weren't asked to
2559          * ignore whitespace, we were asked to correct whitespace
2560          * errors, so let's try matching after whitespace correction.
2561          *
2562          * While checking the preimage against the target, whitespace
2563          * errors in both fixed, we count how large the corresponding
2564          * postimage needs to be.  The postimage prepared by
2565          * apply_one_fragment() has whitespace errors fixed on added
2566          * lines already, but the common lines were propagated as-is,
2567          * which may become longer when their whitespace errors are
2568          * fixed.
2569          */
2570
2571         /* First count added lines in postimage */
2572         postlen = 0;
2573         for (i = 0; i < postimage->nr; i++) {
2574                 if (!(postimage->line[i].flag & LINE_COMMON))
2575                         postlen += postimage->line[i].len;
2576         }
2577
2578         /*
2579          * The preimage may extend beyond the end of the file,
2580          * but in this loop we will only handle the part of the
2581          * preimage that falls within the file.
2582          */
2583         strbuf_init(&fixed, preimage->len + 1);
2584         orig = preimage->buf;
2585         target = img->buf + try;
2586         for (i = 0; i < preimage_limit; i++) {
2587                 size_t oldlen = preimage->line[i].len;
2588                 size_t tgtlen = img->line[try_lno + i].len;
2589                 size_t fixstart = fixed.len;
2590                 struct strbuf tgtfix;
2591                 int match;
2592
2593                 /* Try fixing the line in the preimage */
2594                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2595
2596                 /* Try fixing the line in the target */
2597                 strbuf_init(&tgtfix, tgtlen);
2598                 ws_fix_copy(&tgtfix, target, tgtlen, ws_rule, NULL);
2599
2600                 /*
2601                  * If they match, either the preimage was based on
2602                  * a version before our tree fixed whitespace breakage,
2603                  * or we are lacking a whitespace-fix patch the tree
2604                  * the preimage was based on already had (i.e. target
2605                  * has whitespace breakage, the preimage doesn't).
2606                  * In either case, we are fixing the whitespace breakages
2607                  * so we might as well take the fix together with their
2608                  * real change.
2609                  */
2610                 match = (tgtfix.len == fixed.len - fixstart &&
2611                          !memcmp(tgtfix.buf, fixed.buf + fixstart,
2612                                              fixed.len - fixstart));
2613
2614                 /* Add the length if this is common with the postimage */
2615                 if (preimage->line[i].flag & LINE_COMMON)
2616                         postlen += tgtfix.len;
2617
2618                 strbuf_release(&tgtfix);
2619                 if (!match)
2620                         goto unmatch_exit;
2621
2622                 orig += oldlen;
2623                 target += tgtlen;
2624         }
2625
2626
2627         /*
2628          * Now handle the lines in the preimage that falls beyond the
2629          * end of the file (if any). They will only match if they are
2630          * empty or only contain whitespace (if WS_BLANK_AT_EOL is
2631          * false).
2632          */
2633         for ( ; i < preimage->nr; i++) {
2634                 size_t fixstart = fixed.len; /* start of the fixed preimage */
2635                 size_t oldlen = preimage->line[i].len;
2636                 int j;
2637
2638                 /* Try fixing the line in the preimage */
2639                 ws_fix_copy(&fixed, orig, oldlen, ws_rule, NULL);
2640
2641                 for (j = fixstart; j < fixed.len; j++)
2642                         if (!isspace(fixed.buf[j]))
2643                                 goto unmatch_exit;
2644
2645                 orig += oldlen;
2646         }
2647
2648         /*
2649          * Yes, the preimage is based on an older version that still
2650          * has whitespace breakages unfixed, and fixing them makes the
2651          * hunk match.  Update the context lines in the postimage.
2652          */
2653         fixed_buf = strbuf_detach(&fixed, &fixed_len);
2654         if (postlen < postimage->len)
2655                 postlen = 0;
2656         update_pre_post_images(preimage, postimage,
2657                                fixed_buf, fixed_len, postlen);
2658         return 1;
2659
2660  unmatch_exit:
2661         strbuf_release(&fixed);
2662         return 0;
2663 }
2664
2665 static int find_pos(struct apply_state *state,
2666                     struct image *img,
2667                     struct image *preimage,
2668                     struct image *postimage,
2669                     int line,
2670                     unsigned ws_rule,
2671                     int match_beginning, int match_end)
2672 {
2673         int i;
2674         unsigned long backwards, forwards, try;
2675         int backwards_lno, forwards_lno, try_lno;
2676
2677         /*
2678          * If match_beginning or match_end is specified, there is no
2679          * point starting from a wrong line that will never match and
2680          * wander around and wait for a match at the specified end.
2681          */
2682         if (match_beginning)
2683                 line = 0;
2684         else if (match_end)
2685                 line = img->nr - preimage->nr;
2686
2687         /*
2688          * Because the comparison is unsigned, the following test
2689          * will also take care of a negative line number that can
2690          * result when match_end and preimage is larger than the target.
2691          */
2692         if ((size_t) line > img->nr)
2693                 line = img->nr;
2694
2695         try = 0;
2696         for (i = 0; i < line; i++)
2697                 try += img->line[i].len;
2698
2699         /*
2700          * There's probably some smart way to do this, but I'll leave
2701          * that to the smart and beautiful people. I'm simple and stupid.
2702          */
2703         backwards = try;
2704         backwards_lno = line;
2705         forwards = try;
2706         forwards_lno = line;
2707         try_lno = line;
2708
2709         for (i = 0; ; i++) {
2710                 if (match_fragment(state, img, preimage, postimage,
2711                                    try, try_lno, ws_rule,
2712                                    match_beginning, match_end))
2713                         return try_lno;
2714
2715         again:
2716                 if (backwards_lno == 0 && forwards_lno == img->nr)
2717                         break;
2718
2719                 if (i & 1) {
2720                         if (backwards_lno == 0) {
2721                                 i++;
2722                                 goto again;
2723                         }
2724                         backwards_lno--;
2725                         backwards -= img->line[backwards_lno].len;
2726                         try = backwards;
2727                         try_lno = backwards_lno;
2728                 } else {
2729                         if (forwards_lno == img->nr) {
2730                                 i++;
2731                                 goto again;
2732                         }
2733                         forwards += img->line[forwards_lno].len;
2734                         forwards_lno++;
2735                         try = forwards;
2736                         try_lno = forwards_lno;
2737                 }
2738
2739         }
2740         return -1;
2741 }
2742
2743 static void remove_first_line(struct image *img)
2744 {
2745         img->buf += img->line[0].len;
2746         img->len -= img->line[0].len;
2747         img->line++;
2748         img->nr--;
2749 }
2750
2751 static void remove_last_line(struct image *img)
2752 {
2753         img->len -= img->line[--img->nr].len;
2754 }
2755
2756 /*
2757  * The change from "preimage" and "postimage" has been found to
2758  * apply at applied_pos (counts in line numbers) in "img".
2759  * Update "img" to remove "preimage" and replace it with "postimage".
2760  */
2761 static void update_image(struct apply_state *state,
2762                          struct image *img,
2763                          int applied_pos,
2764                          struct image *preimage,
2765                          struct image *postimage)
2766 {
2767         /*
2768          * remove the copy of preimage at offset in img
2769          * and replace it with postimage
2770          */
2771         int i, nr;
2772         size_t remove_count, insert_count, applied_at = 0;
2773         char *result;
2774         int preimage_limit;
2775
2776         /*
2777          * If we are removing blank lines at the end of img,
2778          * the preimage may extend beyond the end.
2779          * If that is the case, we must be careful only to
2780          * remove the part of the preimage that falls within
2781          * the boundaries of img. Initialize preimage_limit
2782          * to the number of lines in the preimage that falls
2783          * within the boundaries.
2784          */
2785         preimage_limit = preimage->nr;
2786         if (preimage_limit > img->nr - applied_pos)
2787                 preimage_limit = img->nr - applied_pos;
2788
2789         for (i = 0; i < applied_pos; i++)
2790                 applied_at += img->line[i].len;
2791
2792         remove_count = 0;
2793         for (i = 0; i < preimage_limit; i++)
2794                 remove_count += img->line[applied_pos + i].len;
2795         insert_count = postimage->len;
2796
2797         /* Adjust the contents */
2798         result = xmalloc(st_add3(st_sub(img->len, remove_count), insert_count, 1));
2799         memcpy(result, img->buf, applied_at);
2800         memcpy(result + applied_at, postimage->buf, postimage->len);
2801         memcpy(result + applied_at + postimage->len,
2802                img->buf + (applied_at + remove_count),
2803                img->len - (applied_at + remove_count));
2804         free(img->buf);
2805         img->buf = result;
2806         img->len += insert_count - remove_count;
2807         result[img->len] = '\0';
2808
2809         /* Adjust the line table */
2810         nr = img->nr + postimage->nr - preimage_limit;
2811         if (preimage_limit < postimage->nr) {
2812                 /*
2813                  * NOTE: this knows that we never call remove_first_line()
2814                  * on anything other than pre/post image.
2815                  */
2816                 REALLOC_ARRAY(img->line, nr);
2817                 img->line_allocated = img->line;
2818         }
2819         if (preimage_limit != postimage->nr)
2820                 MOVE_ARRAY(img->line + applied_pos + postimage->nr,
2821                            img->line + applied_pos + preimage_limit,
2822                            img->nr - (applied_pos + preimage_limit));
2823         COPY_ARRAY(img->line + applied_pos, postimage->line, postimage->nr);
2824         if (!state->allow_overlap)
2825                 for (i = 0; i < postimage->nr; i++)
2826                         img->line[applied_pos + i].flag |= LINE_PATCHED;
2827         img->nr = nr;
2828 }
2829
2830 /*
2831  * Use the patch-hunk text in "frag" to prepare two images (preimage and
2832  * postimage) for the hunk.  Find lines that match "preimage" in "img" and
2833  * replace the part of "img" with "postimage" text.
2834  */
2835 static int apply_one_fragment(struct apply_state *state,
2836                               struct image *img, struct fragment *frag,
2837                               int inaccurate_eof, unsigned ws_rule,
2838                               int nth_fragment)
2839 {
2840         int match_beginning, match_end;
2841         const char *patch = frag->patch;
2842         int size = frag->size;
2843         char *old, *oldlines;
2844         struct strbuf newlines;
2845         int new_blank_lines_at_end = 0;
2846         int found_new_blank_lines_at_end = 0;
2847         int hunk_linenr = frag->linenr;
2848         unsigned long leading, trailing;
2849         int pos, applied_pos;
2850         struct image preimage;
2851         struct image postimage;
2852
2853         memset(&preimage, 0, sizeof(preimage));
2854         memset(&postimage, 0, sizeof(postimage));
2855         oldlines = xmalloc(size);
2856         strbuf_init(&newlines, size);
2857
2858         old = oldlines;
2859         while (size > 0) {
2860                 char first;
2861                 int len = linelen(patch, size);
2862                 int plen;
2863                 int added_blank_line = 0;
2864                 int is_blank_context = 0;
2865                 size_t start;
2866
2867                 if (!len)
2868                         break;
2869
2870                 /*
2871                  * "plen" is how much of the line we should use for
2872                  * the actual patch data. Normally we just remove the
2873                  * first character on the line, but if the line is
2874                  * followed by "\ No newline", then we also remove the
2875                  * last one (which is the newline, of course).
2876                  */
2877                 plen = len - 1;
2878                 if (len < size && patch[len] == '\\')
2879                         plen--;
2880                 first = *patch;
2881                 if (state->apply_in_reverse) {
2882                         if (first == '-')
2883                                 first = '+';
2884                         else if (first == '+')
2885                                 first = '-';
2886                 }
2887
2888                 switch (first) {
2889                 case '\n':
2890                         /* Newer GNU diff, empty context line */
2891                         if (plen < 0)
2892                                 /* ... followed by '\No newline'; nothing */
2893                                 break;
2894                         *old++ = '\n';
2895                         strbuf_addch(&newlines, '\n');
2896                         add_line_info(&preimage, "\n", 1, LINE_COMMON);
2897                         add_line_info(&postimage, "\n", 1, LINE_COMMON);
2898                         is_blank_context = 1;
2899                         break;
2900                 case ' ':
2901                         if (plen && (ws_rule & WS_BLANK_AT_EOF) &&
2902                             ws_blank_line(patch + 1, plen, ws_rule))
2903                                 is_blank_context = 1;
2904                         /* fallthrough */
2905                 case '-':
2906                         memcpy(old, patch + 1, plen);
2907                         add_line_info(&preimage, old, plen,
2908                                       (first == ' ' ? LINE_COMMON : 0));
2909                         old += plen;
2910                         if (first == '-')
2911                                 break;
2912                         /* fallthrough */
2913                 case '+':
2914                         /* --no-add does not add new lines */
2915                         if (first == '+' && state->no_add)
2916                                 break;
2917
2918                         start = newlines.len;
2919                         if (first != '+' ||
2920                             !state->whitespace_error ||
2921                             state->ws_error_action != correct_ws_error) {
2922                                 strbuf_add(&newlines, patch + 1, plen);
2923                         }
2924                         else {
2925                                 ws_fix_copy(&newlines, patch + 1, plen, ws_rule, &state->applied_after_fixing_ws);
2926                         }
2927                         add_line_info(&postimage, newlines.buf + start, newlines.len - start,
2928                                       (first == '+' ? 0 : LINE_COMMON));
2929                         if (first == '+' &&
2930                             (ws_rule & WS_BLANK_AT_EOF) &&
2931                             ws_blank_line(patch + 1, plen, ws_rule))
2932                                 added_blank_line = 1;
2933                         break;
2934                 case '@': case '\\':
2935                         /* Ignore it, we already handled it */
2936                         break;
2937                 default:
2938                         if (state->apply_verbosity > verbosity_normal)
2939                                 error(_("invalid start of line: '%c'"), first);
2940                         applied_pos = -1;
2941                         goto out;
2942                 }
2943                 if (added_blank_line) {
2944                         if (!new_blank_lines_at_end)
2945                                 found_new_blank_lines_at_end = hunk_linenr;
2946                         new_blank_lines_at_end++;
2947                 }
2948                 else if (is_blank_context)
2949                         ;
2950                 else
2951                         new_blank_lines_at_end = 0;
2952                 patch += len;
2953                 size -= len;
2954                 hunk_linenr++;
2955         }
2956         if (inaccurate_eof &&
2957             old > oldlines && old[-1] == '\n' &&
2958             newlines.len > 0 && newlines.buf[newlines.len - 1] == '\n') {
2959                 old--;
2960                 strbuf_setlen(&newlines, newlines.len - 1);
2961         }
2962
2963         leading = frag->leading;
2964         trailing = frag->trailing;
2965
2966         /*
2967          * A hunk to change lines at the beginning would begin with
2968          * @@ -1,L +N,M @@
2969          * but we need to be careful.  -U0 that inserts before the second
2970          * line also has this pattern.
2971          *
2972          * And a hunk to add to an empty file would begin with
2973          * @@ -0,0 +N,M @@
2974          *
2975          * In other words, a hunk that is (frag->oldpos <= 1) with or
2976          * without leading context must match at the beginning.
2977          */
2978         match_beginning = (!frag->oldpos ||
2979                            (frag->oldpos == 1 && !state->unidiff_zero));
2980
2981         /*
2982          * A hunk without trailing lines must match at the end.
2983          * However, we simply cannot tell if a hunk must match end
2984          * from the lack of trailing lines if the patch was generated
2985          * with unidiff without any context.
2986          */
2987         match_end = !state->unidiff_zero && !trailing;
2988
2989         pos = frag->newpos ? (frag->newpos - 1) : 0;
2990         preimage.buf = oldlines;
2991         preimage.len = old - oldlines;
2992         postimage.buf = newlines.buf;
2993         postimage.len = newlines.len;
2994         preimage.line = preimage.line_allocated;
2995         postimage.line = postimage.line_allocated;
2996
2997         for (;;) {
2998
2999                 applied_pos = find_pos(state, img, &preimage, &postimage, pos,
3000                                        ws_rule, match_beginning, match_end);
3001
3002                 if (applied_pos >= 0)
3003                         break;
3004
3005                 /* Am I at my context limits? */
3006                 if ((leading <= state->p_context) && (trailing <= state->p_context))
3007                         break;
3008                 if (match_beginning || match_end) {
3009                         match_beginning = match_end = 0;
3010                         continue;
3011                 }
3012
3013                 /*
3014                  * Reduce the number of context lines; reduce both
3015                  * leading and trailing if they are equal otherwise
3016                  * just reduce the larger context.
3017                  */
3018                 if (leading >= trailing) {
3019                         remove_first_line(&preimage);
3020                         remove_first_line(&postimage);
3021                         pos--;
3022                         leading--;
3023                 }
3024                 if (trailing > leading) {
3025                         remove_last_line(&preimage);
3026                         remove_last_line(&postimage);
3027                         trailing--;
3028                 }
3029         }
3030
3031         if (applied_pos >= 0) {
3032                 if (new_blank_lines_at_end &&
3033                     preimage.nr + applied_pos >= img->nr &&
3034                     (ws_rule & WS_BLANK_AT_EOF) &&
3035                     state->ws_error_action != nowarn_ws_error) {
3036                         record_ws_error(state, WS_BLANK_AT_EOF, "+", 1,
3037                                         found_new_blank_lines_at_end);
3038                         if (state->ws_error_action == correct_ws_error) {
3039                                 while (new_blank_lines_at_end--)
3040                                         remove_last_line(&postimage);
3041                         }
3042                         /*
3043                          * We would want to prevent write_out_results()
3044                          * from taking place in apply_patch() that follows
3045                          * the callchain led us here, which is:
3046                          * apply_patch->check_patch_list->check_patch->
3047                          * apply_data->apply_fragments->apply_one_fragment
3048                          */
3049                         if (state->ws_error_action == die_on_ws_error)
3050                                 state->apply = 0;
3051                 }
3052
3053                 if (state->apply_verbosity > verbosity_normal && applied_pos != pos) {
3054                         int offset = applied_pos - pos;
3055                         if (state->apply_in_reverse)
3056                                 offset = 0 - offset;
3057                         fprintf_ln(stderr,
3058                                    Q_("Hunk #%d succeeded at %d (offset %d line).",
3059                                       "Hunk #%d succeeded at %d (offset %d lines).",
3060                                       offset),
3061                                    nth_fragment, applied_pos + 1, offset);
3062                 }
3063
3064                 /*
3065                  * Warn if it was necessary to reduce the number
3066                  * of context lines.
3067                  */
3068                 if ((leading != frag->leading ||
3069                      trailing != frag->trailing) && state->apply_verbosity > verbosity_silent)
3070                         fprintf_ln(stderr, _("Context reduced to (%ld/%ld)"
3071                                              " to apply fragment at %d"),
3072                                    leading, trailing, applied_pos+1);
3073                 update_image(state, img, applied_pos, &preimage, &postimage);
3074         } else {
3075                 if (state->apply_verbosity > verbosity_normal)
3076                         error(_("while searching for:\n%.*s"),
3077                               (int)(old - oldlines), oldlines);
3078         }
3079
3080 out:
3081         free(oldlines);
3082         strbuf_release(&newlines);
3083         free(preimage.line_allocated);
3084         free(postimage.line_allocated);
3085
3086         return (applied_pos < 0);
3087 }
3088
3089 static int apply_binary_fragment(struct apply_state *state,
3090                                  struct image *img,
3091                                  struct patch *patch)
3092 {
3093         struct fragment *fragment = patch->fragments;
3094         unsigned long len;
3095         void *dst;
3096
3097         if (!fragment)
3098                 return error(_("missing binary patch data for '%s'"),
3099                              patch->new_name ?
3100                              patch->new_name :
3101                              patch->old_name);
3102
3103         /* Binary patch is irreversible without the optional second hunk */
3104         if (state->apply_in_reverse) {
3105                 if (!fragment->next)
3106                         return error(_("cannot reverse-apply a binary patch "
3107                                        "without the reverse hunk to '%s'"),
3108                                      patch->new_name
3109                                      ? patch->new_name : patch->old_name);
3110                 fragment = fragment->next;
3111         }
3112         switch (fragment->binary_patch_method) {
3113         case BINARY_DELTA_DEFLATED:
3114                 dst = patch_delta(img->buf, img->len, fragment->patch,
3115                                   fragment->size, &len);
3116                 if (!dst)
3117                         return -1;
3118                 clear_image(img);
3119                 img->buf = dst;
3120                 img->len = len;
3121                 return 0;
3122         case BINARY_LITERAL_DEFLATED:
3123                 clear_image(img);
3124                 img->len = fragment->size;
3125                 img->buf = xmemdupz(fragment->patch, img->len);
3126                 return 0;
3127         }
3128         return -1;
3129 }
3130
3131 /*
3132  * Replace "img" with the result of applying the binary patch.
3133  * The binary patch data itself in patch->fragment is still kept
3134  * but the preimage prepared by the caller in "img" is freed here
3135  * or in the helper function apply_binary_fragment() this calls.
3136  */
3137 static int apply_binary(struct apply_state *state,
3138                         struct image *img,
3139                         struct patch *patch)
3140 {
3141         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3142         struct object_id oid;
3143
3144         /*
3145          * For safety, we require patch index line to contain
3146          * full 40-byte textual SHA1 for old and new, at least for now.
3147          */
3148         if (strlen(patch->old_sha1_prefix) != 40 ||
3149             strlen(patch->new_sha1_prefix) != 40 ||
3150             get_oid_hex(patch->old_sha1_prefix, &oid) ||
3151             get_oid_hex(patch->new_sha1_prefix, &oid))
3152                 return error(_("cannot apply binary patch to '%s' "
3153                                "without full index line"), name);
3154
3155         if (patch->old_name) {
3156                 /*
3157                  * See if the old one matches what the patch
3158                  * applies to.
3159                  */
3160                 hash_sha1_file(img->buf, img->len, blob_type, oid.hash);
3161                 if (strcmp(oid_to_hex(&oid), patch->old_sha1_prefix))
3162                         return error(_("the patch applies to '%s' (%s), "
3163                                        "which does not match the "
3164                                        "current contents."),
3165                                      name, oid_to_hex(&oid));
3166         }
3167         else {
3168                 /* Otherwise, the old one must be empty. */
3169                 if (img->len)
3170                         return error(_("the patch applies to an empty "
3171                                        "'%s' but it is not empty"), name);
3172         }
3173
3174         get_oid_hex(patch->new_sha1_prefix, &oid);
3175         if (is_null_oid(&oid)) {
3176                 clear_image(img);
3177                 return 0; /* deletion patch */
3178         }
3179
3180         if (has_sha1_file(oid.hash)) {
3181                 /* We already have the postimage */
3182                 enum object_type type;
3183                 unsigned long size;
3184                 char *result;
3185
3186                 result = read_sha1_file(oid.hash, &type, &size);
3187                 if (!result)
3188                         return error(_("the necessary postimage %s for "
3189                                        "'%s' cannot be read"),
3190                                      patch->new_sha1_prefix, name);
3191                 clear_image(img);
3192                 img->buf = result;
3193                 img->len = size;
3194         } else {
3195                 /*
3196                  * We have verified buf matches the preimage;
3197                  * apply the patch data to it, which is stored
3198                  * in the patch->fragments->{patch,size}.
3199                  */
3200                 if (apply_binary_fragment(state, img, patch))
3201                         return error(_("binary patch does not apply to '%s'"),
3202                                      name);
3203
3204                 /* verify that the result matches */
3205                 hash_sha1_file(img->buf, img->len, blob_type, oid.hash);
3206                 if (strcmp(oid_to_hex(&oid), patch->new_sha1_prefix))
3207                         return error(_("binary patch to '%s' creates incorrect result (expecting %s, got %s)"),
3208                                 name, patch->new_sha1_prefix, oid_to_hex(&oid));
3209         }
3210
3211         return 0;
3212 }
3213
3214 static int apply_fragments(struct apply_state *state, struct image *img, struct patch *patch)
3215 {
3216         struct fragment *frag = patch->fragments;
3217         const char *name = patch->old_name ? patch->old_name : patch->new_name;
3218         unsigned ws_rule = patch->ws_rule;
3219         unsigned inaccurate_eof = patch->inaccurate_eof;
3220         int nth = 0;
3221
3222         if (patch->is_binary)
3223                 return apply_binary(state, img, patch);
3224
3225         while (frag) {
3226                 nth++;
3227                 if (apply_one_fragment(state, img, frag, inaccurate_eof, ws_rule, nth)) {
3228                         error(_("patch failed: %s:%ld"), name, frag->oldpos);
3229                         if (!state->apply_with_reject)
3230                                 return -1;
3231                         frag->rejected = 1;
3232                 }
3233                 frag = frag->next;
3234         }
3235         return 0;
3236 }
3237
3238 static int read_blob_object(struct strbuf *buf, const struct object_id *oid, unsigned mode)
3239 {
3240         if (S_ISGITLINK(mode)) {
3241                 strbuf_grow(buf, 100);
3242                 strbuf_addf(buf, "Subproject commit %s\n", oid_to_hex(oid));
3243         } else {
3244                 enum object_type type;
3245                 unsigned long sz;
3246                 char *result;
3247
3248                 result = read_sha1_file(oid->hash, &type, &sz);
3249                 if (!result)
3250                         return -1;
3251                 /* XXX read_sha1_file NUL-terminates */
3252                 strbuf_attach(buf, result, sz, sz + 1);
3253         }
3254         return 0;
3255 }
3256
3257 static int read_file_or_gitlink(const struct cache_entry *ce, struct strbuf *buf)
3258 {
3259         if (!ce)
3260                 return 0;
3261         return read_blob_object(buf, &ce->oid, ce->ce_mode);
3262 }
3263
3264 static struct patch *in_fn_table(struct apply_state *state, const char *name)
3265 {
3266         struct string_list_item *item;
3267
3268         if (name == NULL)
3269                 return NULL;
3270
3271         item = string_list_lookup(&state->fn_table, name);
3272         if (item != NULL)
3273                 return (struct patch *)item->util;
3274
3275         return NULL;
3276 }
3277
3278 /*
3279  * item->util in the filename table records the status of the path.
3280  * Usually it points at a patch (whose result records the contents
3281  * of it after applying it), but it could be PATH_WAS_DELETED for a
3282  * path that a previously applied patch has already removed, or
3283  * PATH_TO_BE_DELETED for a path that a later patch would remove.
3284  *
3285  * The latter is needed to deal with a case where two paths A and B
3286  * are swapped by first renaming A to B and then renaming B to A;
3287  * moving A to B should not be prevented due to presence of B as we
3288  * will remove it in a later patch.
3289  */
3290 #define PATH_TO_BE_DELETED ((struct patch *) -2)
3291 #define PATH_WAS_DELETED ((struct patch *) -1)
3292
3293 static int to_be_deleted(struct patch *patch)
3294 {
3295         return patch == PATH_TO_BE_DELETED;
3296 }
3297
3298 static int was_deleted(struct patch *patch)
3299 {
3300         return patch == PATH_WAS_DELETED;
3301 }
3302
3303 static void add_to_fn_table(struct apply_state *state, struct patch *patch)
3304 {
3305         struct string_list_item *item;
3306
3307         /*
3308          * Always add new_name unless patch is a deletion
3309          * This should cover the cases for normal diffs,
3310          * file creations and copies
3311          */
3312         if (patch->new_name != NULL) {
3313                 item = string_list_insert(&state->fn_table, patch->new_name);
3314                 item->util = patch;
3315         }
3316
3317         /*
3318          * store a failure on rename/deletion cases because
3319          * later chunks shouldn't patch old names
3320          */
3321         if ((patch->new_name == NULL) || (patch->is_rename)) {
3322                 item = string_list_insert(&state->fn_table, patch->old_name);
3323                 item->util = PATH_WAS_DELETED;
3324         }
3325 }
3326
3327 static void prepare_fn_table(struct apply_state *state, struct patch *patch)
3328 {
3329         /*
3330          * store information about incoming file deletion
3331          */
3332         while (patch) {
3333                 if ((patch->new_name == NULL) || (patch->is_rename)) {
3334                         struct string_list_item *item;
3335                         item = string_list_insert(&state->fn_table, patch->old_name);
3336                         item->util = PATH_TO_BE_DELETED;
3337                 }
3338                 patch = patch->next;
3339         }
3340 }
3341
3342 static int checkout_target(struct index_state *istate,
3343                            struct cache_entry *ce, struct stat *st)
3344 {
3345         struct checkout costate = CHECKOUT_INIT;
3346
3347         costate.refresh_cache = 1;
3348         costate.istate = istate;
3349         if (checkout_entry(ce, &costate, NULL) || lstat(ce->name, st))
3350                 return error(_("cannot checkout %s"), ce->name);
3351         return 0;
3352 }
3353
3354 static struct patch *previous_patch(struct apply_state *state,
3355                                     struct patch *patch,
3356                                     int *gone)
3357 {
3358         struct patch *previous;
3359
3360         *gone = 0;
3361         if (patch->is_copy || patch->is_rename)
3362                 return NULL; /* "git" patches do not depend on the order */
3363
3364         previous = in_fn_table(state, patch->old_name);
3365         if (!previous)
3366                 return NULL;
3367
3368         if (to_be_deleted(previous))
3369                 return NULL; /* the deletion hasn't happened yet */
3370
3371         if (was_deleted(previous))
3372                 *gone = 1;
3373
3374         return previous;
3375 }
3376
3377 static int verify_index_match(const struct cache_entry *ce, struct stat *st)
3378 {
3379         if (S_ISGITLINK(ce->ce_mode)) {
3380                 if (!S_ISDIR(st->st_mode))
3381                         return -1;
3382                 return 0;
3383         }
3384         return ce_match_stat(ce, st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
3385 }
3386
3387 #define SUBMODULE_PATCH_WITHOUT_INDEX 1
3388
3389 static int load_patch_target(struct apply_state *state,
3390                              struct strbuf *buf,
3391                              const struct cache_entry *ce,
3392                              struct stat *st,
3393                              struct patch *patch,
3394                              const char *name,
3395                              unsigned expected_mode)
3396 {
3397         if (state->cached || state->check_index) {
3398                 if (read_file_or_gitlink(ce, buf))
3399                         return error(_("failed to read %s"), name);
3400         } else if (name) {
3401                 if (S_ISGITLINK(expected_mode)) {
3402                         if (ce)
3403                                 return read_file_or_gitlink(ce, buf);
3404                         else
3405                                 return SUBMODULE_PATCH_WITHOUT_INDEX;
3406                 } else if (has_symlink_leading_path(name, strlen(name))) {
3407                         return error(_("reading from '%s' beyond a symbolic link"), name);
3408                 } else {
3409                         if (read_old_data(st, patch, name, buf))
3410                                 return error(_("failed to read %s"), name);
3411                 }
3412         }
3413         return 0;
3414 }
3415
3416 /*
3417  * We are about to apply "patch"; populate the "image" with the
3418  * current version we have, from the working tree or from the index,
3419  * depending on the situation e.g. --cached/--index.  If we are
3420  * applying a non-git patch that incrementally updates the tree,
3421  * we read from the result of a previous diff.
3422  */
3423 static int load_preimage(struct apply_state *state,
3424                          struct image *image,
3425                          struct patch *patch, struct stat *st,
3426                          const struct cache_entry *ce)
3427 {
3428         struct strbuf buf = STRBUF_INIT;
3429         size_t len;
3430         char *img;
3431         struct patch *previous;
3432         int status;
3433
3434         previous = previous_patch(state, patch, &status);
3435         if (status)
3436                 return error(_("path %s has been renamed/deleted"),
3437                              patch->old_name);
3438         if (previous) {
3439                 /* We have a patched copy in memory; use that. */
3440                 strbuf_add(&buf, previous->result, previous->resultsize);
3441         } else {
3442                 status = load_patch_target(state, &buf, ce, st, patch,
3443                                            patch->old_name, patch->old_mode);
3444                 if (status < 0)
3445                         return status;
3446                 else if (status == SUBMODULE_PATCH_WITHOUT_INDEX) {
3447                         /*
3448                          * There is no way to apply subproject
3449                          * patch without looking at the index.
3450                          * NEEDSWORK: shouldn't this be flagged
3451                          * as an error???
3452                          */
3453                         free_fragment_list(patch->fragments);
3454                         patch->fragments = NULL;
3455                 } else if (status) {
3456                         return error(_("failed to read %s"), patch->old_name);
3457                 }
3458         }
3459
3460         img = strbuf_detach(&buf, &len);
3461         prepare_image(image, img, len, !patch->is_binary);
3462         return 0;
3463 }
3464
3465 static int three_way_merge(struct image *image,
3466                            char *path,
3467                            const struct object_id *base,
3468                            const struct object_id *ours,
3469                            const struct object_id *theirs)
3470 {
3471         mmfile_t base_file, our_file, their_file;
3472         mmbuffer_t result = { NULL };
3473         int status;
3474
3475         read_mmblob(&base_file, base);
3476         read_mmblob(&our_file, ours);
3477         read_mmblob(&their_file, theirs);
3478         status = ll_merge(&result, path,
3479                           &base_file, "base",
3480                           &our_file, "ours",
3481                           &their_file, "theirs", NULL);
3482         free(base_file.ptr);
3483         free(our_file.ptr);
3484         free(their_file.ptr);
3485         if (status < 0 || !result.ptr) {
3486                 free(result.ptr);
3487                 return -1;
3488         }
3489         clear_image(image);
3490         image->buf = result.ptr;
3491         image->len = result.size;
3492
3493         return status;
3494 }
3495
3496 /*
3497  * When directly falling back to add/add three-way merge, we read from
3498  * the current contents of the new_name.  In no cases other than that
3499  * this function will be called.
3500  */
3501 static int load_current(struct apply_state *state,
3502                         struct image *image,
3503                         struct patch *patch)
3504 {
3505         struct strbuf buf = STRBUF_INIT;
3506         int status, pos;
3507         size_t len;
3508         char *img;
3509         struct stat st;
3510         struct cache_entry *ce;
3511         char *name = patch->new_name;
3512         unsigned mode = patch->new_mode;
3513
3514         if (!patch->is_new)
3515                 die("BUG: patch to %s is not a creation", patch->old_name);
3516
3517         pos = cache_name_pos(name, strlen(name));
3518         if (pos < 0)
3519                 return error(_("%s: does not exist in index"), name);
3520         ce = active_cache[pos];
3521         if (lstat(name, &st)) {
3522                 if (errno != ENOENT)
3523                         return error_errno("%s", name);
3524                 if (checkout_target(&the_index, ce, &st))
3525                         return -1;
3526         }
3527         if (verify_index_match(ce, &st))
3528                 return error(_("%s: does not match index"), name);
3529
3530         status = load_patch_target(state, &buf, ce, &st, patch, name, mode);
3531         if (status < 0)
3532                 return status;
3533         else if (status)
3534                 return -1;
3535         img = strbuf_detach(&buf, &len);
3536         prepare_image(image, img, len, !patch->is_binary);
3537         return 0;
3538 }
3539
3540 static int try_threeway(struct apply_state *state,
3541                         struct image *image,
3542                         struct patch *patch,
3543                         struct stat *st,
3544                         const struct cache_entry *ce)
3545 {
3546         struct object_id pre_oid, post_oid, our_oid;
3547         struct strbuf buf = STRBUF_INIT;
3548         size_t len;
3549         int status;
3550         char *img;
3551         struct image tmp_image;
3552
3553         /* No point falling back to 3-way merge in these cases */
3554         if (patch->is_delete ||
3555             S_ISGITLINK(patch->old_mode) || S_ISGITLINK(patch->new_mode))
3556                 return -1;
3557
3558         /* Preimage the patch was prepared for */
3559         if (patch->is_new)
3560                 write_sha1_file("", 0, blob_type, pre_oid.hash);
3561         else if (get_oid(patch->old_sha1_prefix, &pre_oid) ||
3562                  read_blob_object(&buf, &pre_oid, patch->old_mode))
3563                 return error(_("repository lacks the necessary blob to fall back on 3-way merge."));
3564
3565         if (state->apply_verbosity > verbosity_silent)
3566                 fprintf(stderr, _("Falling back to three-way merge...\n"));
3567
3568         img = strbuf_detach(&buf, &len);
3569         prepare_image(&tmp_image, img, len, 1);
3570         /* Apply the patch to get the post image */
3571         if (apply_fragments(state, &tmp_image, patch) < 0) {
3572                 clear_image(&tmp_image);
3573                 return -1;
3574         }
3575         /* post_oid is theirs */
3576         write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, post_oid.hash);
3577         clear_image(&tmp_image);
3578
3579         /* our_oid is ours */
3580         if (patch->is_new) {
3581                 if (load_current(state, &tmp_image, patch))
3582                         return error(_("cannot read the current contents of '%s'"),
3583                                      patch->new_name);
3584         } else {
3585                 if (load_preimage(state, &tmp_image, patch, st, ce))
3586                         return error(_("cannot read the current contents of '%s'"),
3587                                      patch->old_name);
3588         }
3589         write_sha1_file(tmp_image.buf, tmp_image.len, blob_type, our_oid.hash);
3590         clear_image(&tmp_image);
3591
3592         /* in-core three-way merge between post and our using pre as base */
3593         status = three_way_merge(image, patch->new_name,
3594                                  &pre_oid, &our_oid, &post_oid);
3595         if (status < 0) {
3596                 if (state->apply_verbosity > verbosity_silent)
3597                         fprintf(stderr,
3598                                 _("Failed to fall back on three-way merge...\n"));
3599                 return status;
3600         }
3601
3602         if (status) {
3603                 patch->conflicted_threeway = 1;
3604                 if (patch->is_new)
3605                         oidclr(&patch->threeway_stage[0]);
3606                 else
3607                         oidcpy(&patch->threeway_stage[0], &pre_oid);
3608                 oidcpy(&patch->threeway_stage[1], &our_oid);
3609                 oidcpy(&patch->threeway_stage[2], &post_oid);
3610                 if (state->apply_verbosity > verbosity_silent)
3611                         fprintf(stderr,
3612                                 _("Applied patch to '%s' with conflicts.\n"),
3613                                 patch->new_name);
3614         } else {
3615                 if (state->apply_verbosity > verbosity_silent)
3616                         fprintf(stderr,
3617                                 _("Applied patch to '%s' cleanly.\n"),
3618                                 patch->new_name);
3619         }
3620         return 0;
3621 }
3622
3623 static int apply_data(struct apply_state *state, struct patch *patch,
3624                       struct stat *st, const struct cache_entry *ce)
3625 {
3626         struct image image;
3627
3628         if (load_preimage(state, &image, patch, st, ce) < 0)
3629                 return -1;
3630
3631         if (patch->direct_to_threeway ||
3632             apply_fragments(state, &image, patch) < 0) {
3633                 /* Note: with --reject, apply_fragments() returns 0 */
3634                 if (!state->threeway || try_threeway(state, &image, patch, st, ce) < 0)
3635                         return -1;
3636         }
3637         patch->result = image.buf;
3638         patch->resultsize = image.len;
3639         add_to_fn_table(state, patch);
3640         free(image.line_allocated);
3641
3642         if (0 < patch->is_delete && patch->resultsize)
3643                 return error(_("removal patch leaves file contents"));
3644
3645         return 0;
3646 }
3647
3648 /*
3649  * If "patch" that we are looking at modifies or deletes what we have,
3650  * we would want it not to lose any local modification we have, either
3651  * in the working tree or in the index.
3652  *
3653  * This also decides if a non-git patch is a creation patch or a
3654  * modification to an existing empty file.  We do not check the state
3655  * of the current tree for a creation patch in this function; the caller
3656  * check_patch() separately makes sure (and errors out otherwise) that
3657  * the path the patch creates does not exist in the current tree.
3658  */
3659 static int check_preimage(struct apply_state *state,
3660                           struct patch *patch,
3661                           struct cache_entry **ce,
3662                           struct stat *st)
3663 {
3664         const char *old_name = patch->old_name;
3665         struct patch *previous = NULL;
3666         int stat_ret = 0, status;
3667         unsigned st_mode = 0;
3668
3669         if (!old_name)
3670                 return 0;
3671
3672         assert(patch->is_new <= 0);
3673         previous = previous_patch(state, patch, &status);
3674
3675         if (status)
3676                 return error(_("path %s has been renamed/deleted"), old_name);
3677         if (previous) {
3678                 st_mode = previous->new_mode;
3679         } else if (!state->cached) {
3680                 stat_ret = lstat(old_name, st);
3681                 if (stat_ret && errno != ENOENT)
3682                         return error_errno("%s", old_name);
3683         }
3684
3685         if (state->check_index && !previous) {
3686                 int pos = cache_name_pos(old_name, strlen(old_name));
3687                 if (pos < 0) {
3688                         if (patch->is_new < 0)
3689                                 goto is_new;
3690                         return error(_("%s: does not exist in index"), old_name);
3691                 }
3692                 *ce = active_cache[pos];
3693                 if (stat_ret < 0) {
3694                         if (checkout_target(&the_index, *ce, st))
3695                                 return -1;
3696                 }
3697                 if (!state->cached && verify_index_match(*ce, st))
3698                         return error(_("%s: does not match index"), old_name);
3699                 if (state->cached)
3700                         st_mode = (*ce)->ce_mode;
3701         } else if (stat_ret < 0) {
3702                 if (patch->is_new < 0)
3703                         goto is_new;
3704                 return error_errno("%s", old_name);
3705         }
3706
3707         if (!state->cached && !previous)
3708                 st_mode = ce_mode_from_stat(*ce, st->st_mode);
3709
3710         if (patch->is_new < 0)
3711                 patch->is_new = 0;
3712         if (!patch->old_mode)
3713                 patch->old_mode = st_mode;
3714         if ((st_mode ^ patch->old_mode) & S_IFMT)
3715                 return error(_("%s: wrong type"), old_name);
3716         if (st_mode != patch->old_mode)
3717                 warning(_("%s has type %o, expected %o"),
3718                         old_name, st_mode, patch->old_mode);
3719         if (!patch->new_mode && !patch->is_delete)
3720                 patch->new_mode = st_mode;
3721         return 0;
3722
3723  is_new:
3724         patch->is_new = 1;
3725         patch->is_delete = 0;
3726         FREE_AND_NULL(patch->old_name);
3727         return 0;
3728 }
3729
3730
3731 #define EXISTS_IN_INDEX 1
3732 #define EXISTS_IN_WORKTREE 2
3733
3734 static int check_to_create(struct apply_state *state,
3735                            const char *new_name,
3736                            int ok_if_exists)
3737 {
3738         struct stat nst;
3739
3740         if (state->check_index &&
3741             cache_name_pos(new_name, strlen(new_name)) >= 0 &&
3742             !ok_if_exists)
3743                 return EXISTS_IN_INDEX;
3744         if (state->cached)
3745                 return 0;
3746
3747         if (!lstat(new_name, &nst)) {
3748                 if (S_ISDIR(nst.st_mode) || ok_if_exists)
3749                         return 0;
3750                 /*
3751                  * A leading component of new_name might be a symlink
3752                  * that is going to be removed with this patch, but
3753                  * still pointing at somewhere that has the path.
3754                  * In such a case, path "new_name" does not exist as
3755                  * far as git is concerned.
3756                  */
3757                 if (has_symlink_leading_path(new_name, strlen(new_name)))
3758                         return 0;
3759
3760                 return EXISTS_IN_WORKTREE;
3761         } else if (!is_missing_file_error(errno)) {
3762                 return error_errno("%s", new_name);
3763         }
3764         return 0;
3765 }
3766
3767 static uintptr_t register_symlink_changes(struct apply_state *state,
3768                                           const char *path,
3769                                           uintptr_t what)
3770 {
3771         struct string_list_item *ent;
3772
3773         ent = string_list_lookup(&state->symlink_changes, path);
3774         if (!ent) {
3775                 ent = string_list_insert(&state->symlink_changes, path);
3776                 ent->util = (void *)0;
3777         }
3778         ent->util = (void *)(what | ((uintptr_t)ent->util));
3779         return (uintptr_t)ent->util;
3780 }
3781
3782 static uintptr_t check_symlink_changes(struct apply_state *state, const char *path)
3783 {
3784         struct string_list_item *ent;
3785
3786         ent = string_list_lookup(&state->symlink_changes, path);
3787         if (!ent)
3788                 return 0;
3789         return (uintptr_t)ent->util;
3790 }
3791
3792 static void prepare_symlink_changes(struct apply_state *state, struct patch *patch)
3793 {
3794         for ( ; patch; patch = patch->next) {
3795                 if ((patch->old_name && S_ISLNK(patch->old_mode)) &&
3796                     (patch->is_rename || patch->is_delete))
3797                         /* the symlink at patch->old_name is removed */
3798                         register_symlink_changes(state, patch->old_name, APPLY_SYMLINK_GOES_AWAY);
3799
3800                 if (patch->new_name && S_ISLNK(patch->new_mode))
3801                         /* the symlink at patch->new_name is created or remains */
3802                         register_symlink_changes(state, patch->new_name, APPLY_SYMLINK_IN_RESULT);
3803         }
3804 }
3805
3806 static int path_is_beyond_symlink_1(struct apply_state *state, struct strbuf *name)
3807 {
3808         do {
3809                 unsigned int change;
3810
3811                 while (--name->len && name->buf[name->len] != '/')
3812                         ; /* scan backwards */
3813                 if (!name->len)
3814                         break;
3815                 name->buf[name->len] = '\0';
3816                 change = check_symlink_changes(state, name->buf);
3817                 if (change & APPLY_SYMLINK_IN_RESULT)
3818                         return 1;
3819                 if (change & APPLY_SYMLINK_GOES_AWAY)
3820                         /*
3821                          * This cannot be "return 0", because we may
3822                          * see a new one created at a higher level.
3823                          */
3824                         continue;
3825
3826                 /* otherwise, check the preimage */
3827                 if (state->check_index) {
3828                         struct cache_entry *ce;
3829
3830                         ce = cache_file_exists(name->buf, name->len, ignore_case);
3831                         if (ce && S_ISLNK(ce->ce_mode))
3832                                 return 1;
3833                 } else {
3834                         struct stat st;
3835                         if (!lstat(name->buf, &st) && S_ISLNK(st.st_mode))
3836                                 return 1;
3837                 }
3838         } while (1);
3839         return 0;
3840 }
3841
3842 static int path_is_beyond_symlink(struct apply_state *state, const char *name_)
3843 {
3844         int ret;
3845         struct strbuf name = STRBUF_INIT;
3846
3847         assert(*name_ != '\0');
3848         strbuf_addstr(&name, name_);
3849         ret = path_is_beyond_symlink_1(state, &name);
3850         strbuf_release(&name);
3851
3852         return ret;
3853 }
3854
3855 static int check_unsafe_path(struct patch *patch)
3856 {
3857         const char *old_name = NULL;
3858         const char *new_name = NULL;
3859         if (patch->is_delete)
3860                 old_name = patch->old_name;
3861         else if (!patch->is_new && !patch->is_copy)
3862                 old_name = patch->old_name;
3863         if (!patch->is_delete)
3864                 new_name = patch->new_name;
3865
3866         if (old_name && !verify_path(old_name))
3867                 return error(_("invalid path '%s'"), old_name);
3868         if (new_name && !verify_path(new_name))
3869                 return error(_("invalid path '%s'"), new_name);
3870         return 0;
3871 }
3872
3873 /*
3874  * Check and apply the patch in-core; leave the result in patch->result
3875  * for the caller to write it out to the final destination.
3876  */
3877 static int check_patch(struct apply_state *state, struct patch *patch)
3878 {
3879         struct stat st;
3880         const char *old_name = patch->old_name;
3881         const char *new_name = patch->new_name;
3882         const char *name = old_name ? old_name : new_name;
3883         struct cache_entry *ce = NULL;
3884         struct patch *tpatch;
3885         int ok_if_exists;
3886         int status;
3887
3888         patch->rejected = 1; /* we will drop this after we succeed */
3889
3890         status = check_preimage(state, patch, &ce, &st);
3891         if (status)
3892                 return status;
3893         old_name = patch->old_name;
3894
3895         /*
3896          * A type-change diff is always split into a patch to delete
3897          * old, immediately followed by a patch to create new (see
3898          * diff.c::run_diff()); in such a case it is Ok that the entry
3899          * to be deleted by the previous patch is still in the working
3900          * tree and in the index.
3901          *
3902          * A patch to swap-rename between A and B would first rename A
3903          * to B and then rename B to A.  While applying the first one,
3904          * the presence of B should not stop A from getting renamed to
3905          * B; ask to_be_deleted() about the later rename.  Removal of
3906          * B and rename from A to B is handled the same way by asking
3907          * was_deleted().
3908          */
3909         if ((tpatch = in_fn_table(state, new_name)) &&
3910             (was_deleted(tpatch) || to_be_deleted(tpatch)))
3911                 ok_if_exists = 1;
3912         else
3913                 ok_if_exists = 0;
3914
3915         if (new_name &&
3916             ((0 < patch->is_new) || patch->is_rename || patch->is_copy)) {
3917                 int err = check_to_create(state, new_name, ok_if_exists);
3918
3919                 if (err && state->threeway) {
3920                         patch->direct_to_threeway = 1;
3921                 } else switch (err) {
3922                 case 0:
3923                         break; /* happy */
3924                 case EXISTS_IN_INDEX:
3925                         return error(_("%s: already exists in index"), new_name);
3926                         break;
3927                 case EXISTS_IN_WORKTREE:
3928                         return error(_("%s: already exists in working directory"),
3929                                      new_name);
3930                 default:
3931                         return err;
3932                 }
3933
3934                 if (!patch->new_mode) {
3935                         if (0 < patch->is_new)
3936                                 patch->new_mode = S_IFREG | 0644;
3937                         else
3938                                 patch->new_mode = patch->old_mode;
3939                 }
3940         }
3941
3942         if (new_name && old_name) {
3943                 int same = !strcmp(old_name, new_name);
3944                 if (!patch->new_mode)
3945                         patch->new_mode = patch->old_mode;
3946                 if ((patch->old_mode ^ patch->new_mode) & S_IFMT) {
3947                         if (same)
3948                                 return error(_("new mode (%o) of %s does not "
3949                                                "match old mode (%o)"),
3950                                         patch->new_mode, new_name,
3951                                         patch->old_mode);
3952                         else
3953                                 return error(_("new mode (%o) of %s does not "
3954                                                "match old mode (%o) of %s"),
3955                                         patch->new_mode, new_name,
3956                                         patch->old_mode, old_name);
3957                 }
3958         }
3959
3960         if (!state->unsafe_paths && check_unsafe_path(patch))
3961                 return -128;
3962
3963         /*
3964          * An attempt to read from or delete a path that is beyond a
3965          * symbolic link will be prevented by load_patch_target() that
3966          * is called at the beginning of apply_data() so we do not
3967          * have to worry about a patch marked with "is_delete" bit
3968          * here.  We however need to make sure that the patch result
3969          * is not deposited to a path that is beyond a symbolic link
3970          * here.
3971          */
3972         if (!patch->is_delete && path_is_beyond_symlink(state, patch->new_name))
3973                 return error(_("affected file '%s' is beyond a symbolic link"),
3974                              patch->new_name);
3975
3976         if (apply_data(state, patch, &st, ce) < 0)
3977                 return error(_("%s: patch does not apply"), name);
3978         patch->rejected = 0;
3979         return 0;
3980 }
3981
3982 static int check_patch_list(struct apply_state *state, struct patch *patch)
3983 {
3984         int err = 0;
3985
3986         prepare_symlink_changes(state, patch);
3987         prepare_fn_table(state, patch);
3988         while (patch) {
3989                 int res;
3990                 if (state->apply_verbosity > verbosity_normal)
3991                         say_patch_name(stderr,
3992                                        _("Checking patch %s..."), patch);
3993                 res = check_patch(state, patch);
3994                 if (res == -128)
3995                         return -128;
3996                 err |= res;
3997                 patch = patch->next;
3998         }
3999         return err;
4000 }
4001
4002 static int read_apply_cache(struct apply_state *state)
4003 {
4004         if (state->index_file)
4005                 return read_cache_from(state->index_file);
4006         else
4007                 return read_cache();
4008 }
4009
4010 /* This function tries to read the object name from the current index */
4011 static int get_current_oid(struct apply_state *state, const char *path,
4012                            struct object_id *oid)
4013 {
4014         int pos;
4015
4016         if (read_apply_cache(state) < 0)
4017                 return -1;
4018         pos = cache_name_pos(path, strlen(path));
4019         if (pos < 0)
4020                 return -1;
4021         oidcpy(oid, &active_cache[pos]->oid);
4022         return 0;
4023 }
4024
4025 static int preimage_oid_in_gitlink_patch(struct patch *p, struct object_id *oid)
4026 {
4027         /*
4028          * A usable gitlink patch has only one fragment (hunk) that looks like:
4029          * @@ -1 +1 @@
4030          * -Subproject commit <old sha1>
4031          * +Subproject commit <new sha1>
4032          * or
4033          * @@ -1 +0,0 @@
4034          * -Subproject commit <old sha1>
4035          * for a removal patch.
4036          */
4037         struct fragment *hunk = p->fragments;
4038         static const char heading[] = "-Subproject commit ";
4039         char *preimage;
4040
4041         if (/* does the patch have only one hunk? */
4042             hunk && !hunk->next &&
4043             /* is its preimage one line? */
4044             hunk->oldpos == 1 && hunk->oldlines == 1 &&
4045             /* does preimage begin with the heading? */
4046             (preimage = memchr(hunk->patch, '\n', hunk->size)) != NULL &&
4047             starts_with(++preimage, heading) &&
4048             /* does it record full SHA-1? */
4049             !get_oid_hex(preimage + sizeof(heading) - 1, oid) &&
4050             preimage[sizeof(heading) + GIT_SHA1_HEXSZ - 1] == '\n' &&
4051             /* does the abbreviated name on the index line agree with it? */
4052             starts_with(preimage + sizeof(heading) - 1, p->old_sha1_prefix))
4053                 return 0; /* it all looks fine */
4054
4055         /* we may have full object name on the index line */
4056         return get_oid_hex(p->old_sha1_prefix, oid);
4057 }
4058
4059 /* Build an index that contains the just the files needed for a 3way merge */
4060 static int build_fake_ancestor(struct apply_state *state, struct patch *list)
4061 {
4062         struct patch *patch;
4063         struct index_state result = { NULL };
4064         static struct lock_file lock;
4065         int res;
4066
4067         /* Once we start supporting the reverse patch, it may be
4068          * worth showing the new sha1 prefix, but until then...
4069          */
4070         for (patch = list; patch; patch = patch->next) {
4071                 struct object_id oid;
4072                 struct cache_entry *ce;
4073                 const char *name;
4074
4075                 name = patch->old_name ? patch->old_name : patch->new_name;
4076                 if (0 < patch->is_new)
4077                         continue;
4078
4079                 if (S_ISGITLINK(patch->old_mode)) {
4080                         if (!preimage_oid_in_gitlink_patch(patch, &oid))
4081                                 ; /* ok, the textual part looks sane */
4082                         else
4083                                 return error(_("sha1 information is lacking or "
4084                                                "useless for submodule %s"), name);
4085                 } else if (!get_oid_blob(patch->old_sha1_prefix, &oid)) {
4086                         ; /* ok */
4087                 } else if (!patch->lines_added && !patch->lines_deleted) {
4088                         /* mode-only change: update the current */
4089                         if (get_current_oid(state, patch->old_name, &oid))
4090                                 return error(_("mode change for %s, which is not "
4091                                                "in current HEAD"), name);
4092                 } else
4093                         return error(_("sha1 information is lacking or useless "
4094                                        "(%s)."), name);
4095
4096                 ce = make_cache_entry(patch->old_mode, oid.hash, name, 0, 0);
4097                 if (!ce)
4098                         return error(_("make_cache_entry failed for path '%s'"),
4099                                      name);
4100                 if (add_index_entry(&result, ce, ADD_CACHE_OK_TO_ADD)) {
4101                         free(ce);
4102                         return error(_("could not add %s to temporary index"),
4103                                      name);
4104                 }
4105         }
4106
4107         hold_lock_file_for_update(&lock, state->fake_ancestor, LOCK_DIE_ON_ERROR);
4108         res = write_locked_index(&result, &lock, COMMIT_LOCK);
4109         discard_index(&result);
4110
4111         if (res)
4112                 return error(_("could not write temporary index to %s"),
4113                              state->fake_ancestor);
4114
4115         return 0;
4116 }
4117
4118 static void stat_patch_list(struct apply_state *state, struct patch *patch)
4119 {
4120         int files, adds, dels;
4121
4122         for (files = adds = dels = 0 ; patch ; patch = patch->next) {
4123                 files++;
4124                 adds += patch->lines_added;
4125                 dels += patch->lines_deleted;
4126                 show_stats(state, patch);
4127         }
4128
4129         print_stat_summary(stdout, files, adds, dels);
4130 }
4131
4132 static void numstat_patch_list(struct apply_state *state,
4133                                struct patch *patch)
4134 {
4135         for ( ; patch; patch = patch->next) {
4136                 const char *name;
4137                 name = patch->new_name ? patch->new_name : patch->old_name;
4138                 if (patch->is_binary)
4139                         printf("-\t-\t");
4140                 else
4141                         printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
4142                 write_name_quoted(name, stdout, state->line_termination);
4143         }
4144 }
4145
4146 static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
4147 {
4148         if (mode)
4149                 printf(" %s mode %06o %s\n", newdelete, mode, name);
4150         else
4151                 printf(" %s %s\n", newdelete, name);
4152 }
4153
4154 static void show_mode_change(struct patch *p, int show_name)
4155 {
4156         if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
4157                 if (show_name)
4158                         printf(" mode change %06o => %06o %s\n",
4159                                p->old_mode, p->new_mode, p->new_name);
4160                 else
4161                         printf(" mode change %06o => %06o\n",
4162                                p->old_mode, p->new_mode);
4163         }
4164 }
4165
4166 static void show_rename_copy(struct patch *p)
4167 {
4168         const char *renamecopy = p->is_rename ? "rename" : "copy";
4169         const char *old, *new;
4170
4171         /* Find common prefix */
4172         old = p->old_name;
4173         new = p->new_name;
4174         while (1) {
4175                 const char *slash_old, *slash_new;
4176                 slash_old = strchr(old, '/');
4177                 slash_new = strchr(new, '/');
4178                 if (!slash_old ||
4179                     !slash_new ||
4180                     slash_old - old != slash_new - new ||
4181                     memcmp(old, new, slash_new - new))
4182                         break;
4183                 old = slash_old + 1;
4184                 new = slash_new + 1;
4185         }
4186         /* p->old_name thru old is the common prefix, and old and new
4187          * through the end of names are renames
4188          */
4189         if (old != p->old_name)
4190                 printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
4191                        (int)(old - p->old_name), p->old_name,
4192                        old, new, p->score);
4193         else
4194                 printf(" %s %s => %s (%d%%)\n", renamecopy,
4195                        p->old_name, p->new_name, p->score);
4196         show_mode_change(p, 0);
4197 }
4198
4199 static void summary_patch_list(struct patch *patch)
4200 {
4201         struct patch *p;
4202
4203         for (p = patch; p; p = p->next) {
4204                 if (p->is_new)
4205                         show_file_mode_name("create", p->new_mode, p->new_name);
4206                 else if (p->is_delete)
4207                         show_file_mode_name("delete", p->old_mode, p->old_name);
4208                 else {
4209                         if (p->is_rename || p->is_copy)
4210                                 show_rename_copy(p);
4211                         else {
4212                                 if (p->score) {
4213                                         printf(" rewrite %s (%d%%)\n",
4214                                                p->new_name, p->score);
4215                                         show_mode_change(p, 0);
4216                                 }
4217                                 else
4218                                         show_mode_change(p, 1);
4219                         }
4220                 }
4221         }
4222 }
4223
4224 static void patch_stats(struct apply_state *state, struct patch *patch)
4225 {
4226         int lines = patch->lines_added + patch->lines_deleted;
4227
4228         if (lines > state->max_change)
4229                 state->max_change = lines;
4230         if (patch->old_name) {
4231                 int len = quote_c_style(patch->old_name, NULL, NULL, 0);
4232                 if (!len)
4233                         len = strlen(patch->old_name);
4234                 if (len > state->max_len)
4235                         state->max_len = len;
4236         }
4237         if (patch->new_name) {
4238                 int len = quote_c_style(patch->new_name, NULL, NULL, 0);
4239                 if (!len)
4240                         len = strlen(patch->new_name);
4241                 if (len > state->max_len)
4242                         state->max_len = len;
4243         }
4244 }
4245
4246 static int remove_file(struct apply_state *state, struct patch *patch, int rmdir_empty)
4247 {
4248         if (state->update_index) {
4249                 if (remove_file_from_cache(patch->old_name) < 0)
4250                         return error(_("unable to remove %s from index"), patch->old_name);
4251         }
4252         if (!state->cached) {
4253                 if (!remove_or_warn(patch->old_mode, patch->old_name) && rmdir_empty) {
4254                         remove_path(patch->old_name);
4255                 }
4256         }
4257         return 0;
4258 }
4259
4260 static int add_index_file(struct apply_state *state,
4261                           const char *path,
4262                           unsigned mode,
4263                           void *buf,
4264                           unsigned long size)
4265 {
4266         struct stat st;
4267         struct cache_entry *ce;
4268         int namelen = strlen(path);
4269         unsigned ce_size = cache_entry_size(namelen);
4270
4271         if (!state->update_index)
4272                 return 0;
4273
4274         ce = xcalloc(1, ce_size);
4275         memcpy(ce->name, path, namelen);
4276         ce->ce_mode = create_ce_mode(mode);
4277         ce->ce_flags = create_ce_flags(0);
4278         ce->ce_namelen = namelen;
4279         if (S_ISGITLINK(mode)) {
4280                 const char *s;
4281
4282                 if (!skip_prefix(buf, "Subproject commit ", &s) ||
4283                     get_oid_hex(s, &ce->oid)) {
4284                         free(ce);
4285                        return error(_("corrupt patch for submodule %s"), path);
4286                 }
4287         } else {
4288                 if (!state->cached) {
4289                         if (lstat(path, &st) < 0) {
4290                                 free(ce);
4291                                 return error_errno(_("unable to stat newly "
4292                                                      "created file '%s'"),
4293                                                    path);
4294                         }
4295                         fill_stat_cache_info(ce, &st);
4296                 }
4297                 if (write_sha1_file(buf, size, blob_type, ce->oid.hash) < 0) {
4298                         free(ce);
4299                         return error(_("unable to create backing store "
4300                                        "for newly created file %s"), path);
4301                 }
4302         }
4303         if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4304                 free(ce);
4305                 return error(_("unable to add cache entry for %s"), path);
4306         }
4307
4308         return 0;
4309 }
4310
4311 /*
4312  * Returns:
4313  *  -1 if an unrecoverable error happened
4314  *   0 if everything went well
4315  *   1 if a recoverable error happened
4316  */
4317 static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
4318 {
4319         int fd, res;
4320         struct strbuf nbuf = STRBUF_INIT;
4321
4322         if (S_ISGITLINK(mode)) {
4323                 struct stat st;
4324                 if (!lstat(path, &st) && S_ISDIR(st.st_mode))
4325                         return 0;
4326                 return !!mkdir(path, 0777);
4327         }
4328
4329         if (has_symlinks && S_ISLNK(mode))
4330                 /* Although buf:size is counted string, it also is NUL
4331                  * terminated.
4332                  */
4333                 return !!symlink(buf, path);
4334
4335         fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
4336         if (fd < 0)
4337                 return 1;
4338
4339         if (convert_to_working_tree(path, buf, size, &nbuf)) {
4340                 size = nbuf.len;
4341                 buf  = nbuf.buf;
4342         }
4343
4344         res = write_in_full(fd, buf, size) < 0;
4345         if (res)
4346                 error_errno(_("failed to write to '%s'"), path);
4347         strbuf_release(&nbuf);
4348
4349         if (close(fd) < 0 && !res)
4350                 return error_errno(_("closing file '%s'"), path);
4351
4352         return res ? -1 : 0;
4353 }
4354
4355 /*
4356  * We optimistically assume that the directories exist,
4357  * which is true 99% of the time anyway. If they don't,
4358  * we create them and try again.
4359  *
4360  * Returns:
4361  *   -1 on error
4362  *   0 otherwise
4363  */
4364 static int create_one_file(struct apply_state *state,
4365                            char *path,
4366                            unsigned mode,
4367                            const char *buf,
4368                            unsigned long size)
4369 {
4370         int res;
4371
4372         if (state->cached)
4373                 return 0;
4374
4375         res = try_create_file(path, mode, buf, size);
4376         if (res < 0)
4377                 return -1;
4378         if (!res)
4379                 return 0;
4380
4381         if (errno == ENOENT) {
4382                 if (safe_create_leading_directories(path))
4383                         return 0;
4384                 res = try_create_file(path, mode, buf, size);
4385                 if (res < 0)
4386                         return -1;
4387                 if (!res)
4388                         return 0;
4389         }
4390
4391         if (errno == EEXIST || errno == EACCES) {
4392                 /* We may be trying to create a file where a directory
4393                  * used to be.
4394                  */
4395                 struct stat st;
4396                 if (!lstat(path, &st) && (!S_ISDIR(st.st_mode) || !rmdir(path)))
4397                         errno = EEXIST;
4398         }
4399
4400         if (errno == EEXIST) {
4401                 unsigned int nr = getpid();
4402
4403                 for (;;) {
4404                         char newpath[PATH_MAX];
4405                         mksnpath(newpath, sizeof(newpath), "%s~%u", path, nr);
4406                         res = try_create_file(newpath, mode, buf, size);
4407                         if (res < 0)
4408                                 return -1;
4409                         if (!res) {
4410                                 if (!rename(newpath, path))
4411                                         return 0;
4412                                 unlink_or_warn(newpath);
4413                                 break;
4414                         }
4415                         if (errno != EEXIST)
4416                                 break;
4417                         ++nr;
4418                 }
4419         }
4420         return error_errno(_("unable to write file '%s' mode %o"),
4421                            path, mode);
4422 }
4423
4424 static int add_conflicted_stages_file(struct apply_state *state,
4425                                        struct patch *patch)
4426 {
4427         int stage, namelen;
4428         unsigned ce_size, mode;
4429         struct cache_entry *ce;
4430
4431         if (!state->update_index)
4432                 return 0;
4433         namelen = strlen(patch->new_name);
4434         ce_size = cache_entry_size(namelen);
4435         mode = patch->new_mode ? patch->new_mode : (S_IFREG | 0644);
4436
4437         remove_file_from_cache(patch->new_name);
4438         for (stage = 1; stage < 4; stage++) {
4439                 if (is_null_oid(&patch->threeway_stage[stage - 1]))
4440                         continue;
4441                 ce = xcalloc(1, ce_size);
4442                 memcpy(ce->name, patch->new_name, namelen);
4443                 ce->ce_mode = create_ce_mode(mode);
4444                 ce->ce_flags = create_ce_flags(stage);
4445                 ce->ce_namelen = namelen;
4446                 oidcpy(&ce->oid, &patch->threeway_stage[stage - 1]);
4447                 if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0) {
4448                         free(ce);
4449                         return error(_("unable to add cache entry for %s"),
4450                                      patch->new_name);
4451                 }
4452         }
4453
4454         return 0;
4455 }
4456
4457 static int create_file(struct apply_state *state, struct patch *patch)
4458 {
4459         char *path = patch->new_name;
4460         unsigned mode = patch->new_mode;
4461         unsigned long size = patch->resultsize;
4462         char *buf = patch->result;
4463
4464         if (!mode)
4465                 mode = S_IFREG | 0644;
4466         if (create_one_file(state, path, mode, buf, size))
4467                 return -1;
4468
4469         if (patch->conflicted_threeway)
4470                 return add_conflicted_stages_file(state, patch);
4471         else
4472                 return add_index_file(state, path, mode, buf, size);
4473 }
4474
4475 /* phase zero is to remove, phase one is to create */
4476 static int write_out_one_result(struct apply_state *state,
4477                                 struct patch *patch,
4478                                 int phase)
4479 {
4480         if (patch->is_delete > 0) {
4481                 if (phase == 0)
4482                         return remove_file(state, patch, 1);
4483                 return 0;
4484         }
4485         if (patch->is_new > 0 || patch->is_copy) {
4486                 if (phase == 1)
4487                         return create_file(state, patch);
4488                 return 0;
4489         }
4490         /*
4491          * Rename or modification boils down to the same
4492          * thing: remove the old, write the new
4493          */
4494         if (phase == 0)
4495                 return remove_file(state, patch, patch->is_rename);
4496         if (phase == 1)
4497                 return create_file(state, patch);
4498         return 0;
4499 }
4500
4501 static int write_out_one_reject(struct apply_state *state, struct patch *patch)
4502 {
4503         FILE *rej;
4504         char namebuf[PATH_MAX];
4505         struct fragment *frag;
4506         int cnt = 0;
4507         struct strbuf sb = STRBUF_INIT;
4508
4509         for (cnt = 0, frag = patch->fragments; frag; frag = frag->next) {
4510                 if (!frag->rejected)
4511                         continue;
4512                 cnt++;
4513         }
4514
4515         if (!cnt) {
4516                 if (state->apply_verbosity > verbosity_normal)
4517                         say_patch_name(stderr,
4518                                        _("Applied patch %s cleanly."), patch);
4519                 return 0;
4520         }
4521
4522         /* This should not happen, because a removal patch that leaves
4523          * contents are marked "rejected" at the patch level.
4524          */
4525         if (!patch->new_name)
4526                 die(_("internal error"));
4527
4528         /* Say this even without --verbose */
4529         strbuf_addf(&sb, Q_("Applying patch %%s with %d reject...",
4530                             "Applying patch %%s with %d rejects...",
4531                             cnt),
4532                     cnt);
4533         if (state->apply_verbosity > verbosity_silent)
4534                 say_patch_name(stderr, sb.buf, patch);
4535         strbuf_release(&sb);
4536
4537         cnt = strlen(patch->new_name);
4538         if (ARRAY_SIZE(namebuf) <= cnt + 5) {
4539                 cnt = ARRAY_SIZE(namebuf) - 5;
4540                 warning(_("truncating .rej filename to %.*s.rej"),
4541                         cnt - 1, patch->new_name);
4542         }
4543         memcpy(namebuf, patch->new_name, cnt);
4544         memcpy(namebuf + cnt, ".rej", 5);
4545
4546         rej = fopen(namebuf, "w");
4547         if (!rej)
4548                 return error_errno(_("cannot open %s"), namebuf);
4549
4550         /* Normal git tools never deal with .rej, so do not pretend
4551          * this is a git patch by saying --git or giving extended
4552          * headers.  While at it, maybe please "kompare" that wants
4553          * the trailing TAB and some garbage at the end of line ;-).
4554          */
4555         fprintf(rej, "diff a/%s b/%s\t(rejected hunks)\n",
4556                 patch->new_name, patch->new_name);
4557         for (cnt = 1, frag = patch->fragments;
4558              frag;
4559              cnt++, frag = frag->next) {
4560                 if (!frag->rejected) {
4561                         if (state->apply_verbosity > verbosity_silent)
4562                                 fprintf_ln(stderr, _("Hunk #%d applied cleanly."), cnt);
4563                         continue;
4564                 }
4565                 if (state->apply_verbosity > verbosity_silent)
4566                         fprintf_ln(stderr, _("Rejected hunk #%d."), cnt);
4567                 fprintf(rej, "%.*s", frag->size, frag->patch);
4568                 if (frag->patch[frag->size-1] != '\n')
4569                         fputc('\n', rej);
4570         }
4571         fclose(rej);
4572         return -1;
4573 }
4574
4575 /*
4576  * Returns:
4577  *  -1 if an error happened
4578  *   0 if the patch applied cleanly
4579  *   1 if the patch did not apply cleanly
4580  */
4581 static int write_out_results(struct apply_state *state, struct patch *list)
4582 {
4583         int phase;
4584         int errs = 0;
4585         struct patch *l;
4586         struct string_list cpath = STRING_LIST_INIT_DUP;
4587
4588         for (phase = 0; phase < 2; phase++) {
4589                 l = list;
4590                 while (l) {
4591                         if (l->rejected)
4592                                 errs = 1;
4593                         else {
4594                                 if (write_out_one_result(state, l, phase)) {
4595                                         string_list_clear(&cpath, 0);
4596                                         return -1;
4597                                 }
4598                                 if (phase == 1) {
4599                                         if (write_out_one_reject(state, l))
4600                                                 errs = 1;
4601                                         if (l->conflicted_threeway) {
4602                                                 string_list_append(&cpath, l->new_name);
4603                                                 errs = 1;
4604                                         }
4605                                 }
4606                         }
4607                         l = l->next;
4608                 }
4609         }
4610
4611         if (cpath.nr) {
4612                 struct string_list_item *item;
4613
4614                 string_list_sort(&cpath);
4615                 if (state->apply_verbosity > verbosity_silent) {
4616                         for_each_string_list_item(item, &cpath)
4617                                 fprintf(stderr, "U %s\n", item->string);
4618                 }
4619                 string_list_clear(&cpath, 0);
4620
4621                 rerere(0);
4622         }
4623
4624         return errs;
4625 }
4626
4627 /*
4628  * Try to apply a patch.
4629  *
4630  * Returns:
4631  *  -128 if a bad error happened (like patch unreadable)
4632  *  -1 if patch did not apply and user cannot deal with it
4633  *   0 if the patch applied
4634  *   1 if the patch did not apply but user might fix it
4635  */
4636 static int apply_patch(struct apply_state *state,
4637                        int fd,
4638                        const char *filename,
4639                        int options)
4640 {
4641         size_t offset;
4642         struct strbuf buf = STRBUF_INIT; /* owns the patch text */
4643         struct patch *list = NULL, **listp = &list;
4644         int skipped_patch = 0;
4645         int res = 0;
4646
4647         state->patch_input_file = filename;
4648         if (read_patch_file(&buf, fd) < 0)
4649                 return -128;
4650         offset = 0;
4651         while (offset < buf.len) {
4652                 struct patch *patch;
4653                 int nr;
4654
4655                 patch = xcalloc(1, sizeof(*patch));
4656                 patch->inaccurate_eof = !!(options & APPLY_OPT_INACCURATE_EOF);
4657                 patch->recount =  !!(options & APPLY_OPT_RECOUNT);
4658                 nr = parse_chunk(state, buf.buf + offset, buf.len - offset, patch);
4659                 if (nr < 0) {
4660                         free_patch(patch);
4661                         if (nr == -128) {
4662                                 res = -128;
4663                                 goto end;
4664                         }
4665                         break;
4666                 }
4667                 if (state->apply_in_reverse)
4668                         reverse_patches(patch);
4669                 if (use_patch(state, patch)) {
4670                         patch_stats(state, patch);
4671                         *listp = patch;
4672                         listp = &patch->next;
4673                 }
4674                 else {
4675                         if (state->apply_verbosity > verbosity_normal)
4676                                 say_patch_name(stderr, _("Skipped patch '%s'."), patch);
4677                         free_patch(patch);
4678                         skipped_patch++;
4679                 }
4680                 offset += nr;
4681         }
4682
4683         if (!list && !skipped_patch) {
4684                 error(_("unrecognized input"));
4685                 res = -128;
4686                 goto end;
4687         }
4688
4689         if (state->whitespace_error && (state->ws_error_action == die_on_ws_error))
4690                 state->apply = 0;
4691
4692         state->update_index = state->check_index && state->apply;
4693         if (state->update_index && state->newfd < 0) {
4694                 if (state->index_file)
4695                         state->newfd = hold_lock_file_for_update(state->lock_file,
4696                                                                  state->index_file,
4697                                                                  LOCK_DIE_ON_ERROR);
4698                 else
4699                         state->newfd = hold_locked_index(state->lock_file, LOCK_DIE_ON_ERROR);
4700         }
4701
4702         if (state->check_index && read_apply_cache(state) < 0) {
4703                 error(_("unable to read index file"));
4704                 res = -128;
4705                 goto end;
4706         }
4707
4708         if (state->check || state->apply) {
4709                 int r = check_patch_list(state, list);
4710                 if (r == -128) {
4711                         res = -128;
4712                         goto end;
4713                 }
4714                 if (r < 0 && !state->apply_with_reject) {
4715                         res = -1;
4716                         goto end;
4717                 }
4718         }
4719
4720         if (state->apply) {
4721                 int write_res = write_out_results(state, list);
4722                 if (write_res < 0) {
4723                         res = -128;
4724                         goto end;
4725                 }
4726                 if (write_res > 0) {
4727                         /* with --3way, we still need to write the index out */
4728                         res = state->apply_with_reject ? -1 : 1;
4729                         goto end;
4730                 }
4731         }
4732
4733         if (state->fake_ancestor &&
4734             build_fake_ancestor(state, list)) {
4735                 res = -128;
4736                 goto end;
4737         }
4738
4739         if (state->diffstat && state->apply_verbosity > verbosity_silent)
4740                 stat_patch_list(state, list);
4741
4742         if (state->numstat && state->apply_verbosity > verbosity_silent)
4743                 numstat_patch_list(state, list);
4744
4745         if (state->summary && state->apply_verbosity > verbosity_silent)
4746                 summary_patch_list(list);
4747
4748 end:
4749         free_patch_list(list);
4750         strbuf_release(&buf);
4751         string_list_clear(&state->fn_table, 0);
4752         return res;
4753 }
4754
4755 static int apply_option_parse_exclude(const struct option *opt,
4756                                       const char *arg, int unset)
4757 {
4758         struct apply_state *state = opt->value;
4759         add_name_limit(state, arg, 1);
4760         return 0;
4761 }
4762
4763 static int apply_option_parse_include(const struct option *opt,
4764                                       const char *arg, int unset)
4765 {
4766         struct apply_state *state = opt->value;
4767         add_name_limit(state, arg, 0);
4768         state->has_include = 1;
4769         return 0;
4770 }
4771
4772 static int apply_option_parse_p(const struct option *opt,
4773                                 const char *arg,
4774                                 int unset)
4775 {
4776         struct apply_state *state = opt->value;
4777         state->p_value = atoi(arg);
4778         state->p_value_known = 1;
4779         return 0;
4780 }
4781
4782 static int apply_option_parse_space_change(const struct option *opt,
4783                                            const char *arg, int unset)
4784 {
4785         struct apply_state *state = opt->value;
4786         if (unset)
4787                 state->ws_ignore_action = ignore_ws_none;
4788         else
4789                 state->ws_ignore_action = ignore_ws_change;
4790         return 0;
4791 }
4792
4793 static int apply_option_parse_whitespace(const struct option *opt,
4794                                          const char *arg, int unset)
4795 {
4796         struct apply_state *state = opt->value;
4797         state->whitespace_option = arg;
4798         if (parse_whitespace_option(state, arg))
4799                 exit(1);
4800         return 0;
4801 }
4802
4803 static int apply_option_parse_directory(const struct option *opt,
4804                                         const char *arg, int unset)
4805 {
4806         struct apply_state *state = opt->value;
4807         strbuf_reset(&state->root);
4808         strbuf_addstr(&state->root, arg);
4809         strbuf_complete(&state->root, '/');
4810         return 0;
4811 }
4812
4813 int apply_all_patches(struct apply_state *state,
4814                       int argc,
4815                       const char **argv,
4816                       int options)
4817 {
4818         int i;
4819         int res;
4820         int errs = 0;
4821         int read_stdin = 1;
4822
4823         for (i = 0; i < argc; i++) {
4824                 const char *arg = argv[i];
4825                 char *to_free = NULL;
4826                 int fd;
4827
4828                 if (!strcmp(arg, "-")) {
4829                         res = apply_patch(state, 0, "<stdin>", options);
4830                         if (res < 0)
4831                                 goto end;
4832                         errs |= res;
4833                         read_stdin = 0;
4834                         continue;
4835                 } else
4836                         arg = to_free = prefix_filename(state->prefix, arg);
4837
4838                 fd = open(arg, O_RDONLY);
4839                 if (fd < 0) {
4840                         error(_("can't open patch '%s': %s"), arg, strerror(errno));
4841                         res = -128;
4842                         free(to_free);
4843                         goto end;
4844                 }
4845                 read_stdin = 0;
4846                 set_default_whitespace_mode(state);
4847                 res = apply_patch(state, fd, arg, options);
4848                 close(fd);
4849                 free(to_free);
4850                 if (res < 0)
4851                         goto end;
4852                 errs |= res;
4853         }
4854         set_default_whitespace_mode(state);
4855         if (read_stdin) {
4856                 res = apply_patch(state, 0, "<stdin>", options);
4857                 if (res < 0)
4858                         goto end;
4859                 errs |= res;
4860         }
4861
4862         if (state->whitespace_error) {
4863                 if (state->squelch_whitespace_errors &&
4864                     state->squelch_whitespace_errors < state->whitespace_error) {
4865                         int squelched =
4866                                 state->whitespace_error - state->squelch_whitespace_errors;
4867                         warning(Q_("squelched %d whitespace error",
4868                                    "squelched %d whitespace errors",
4869                                    squelched),
4870                                 squelched);
4871                 }
4872                 if (state->ws_error_action == die_on_ws_error) {
4873                         error(Q_("%d line adds whitespace errors.",
4874                                  "%d lines add whitespace errors.",
4875                                  state->whitespace_error),
4876                               state->whitespace_error);
4877                         res = -128;
4878                         goto end;
4879                 }
4880                 if (state->applied_after_fixing_ws && state->apply)
4881                         warning(Q_("%d line applied after"
4882                                    " fixing whitespace errors.",
4883                                    "%d lines applied after"
4884                                    " fixing whitespace errors.",
4885                                    state->applied_after_fixing_ws),
4886                                 state->applied_after_fixing_ws);
4887                 else if (state->whitespace_error)
4888                         warning(Q_("%d line adds whitespace errors.",
4889                                    "%d lines add whitespace errors.",
4890                                    state->whitespace_error),
4891                                 state->whitespace_error);
4892         }
4893
4894         if (state->update_index) {
4895                 res = write_locked_index(&the_index, state->lock_file, COMMIT_LOCK);
4896                 if (res) {
4897                         error(_("Unable to write new index file"));
4898                         res = -128;
4899                         goto end;
4900                 }
4901                 state->newfd = -1;
4902         }
4903
4904         res = !!errs;
4905
4906 end:
4907         if (state->newfd >= 0) {
4908                 rollback_lock_file(state->lock_file);
4909                 state->newfd = -1;
4910         }
4911
4912         if (state->apply_verbosity <= verbosity_silent) {
4913                 set_error_routine(state->saved_error_routine);
4914                 set_warn_routine(state->saved_warn_routine);
4915         }
4916
4917         if (res > -1)
4918                 return res;
4919         return (res == -1 ? 1 : 128);
4920 }
4921
4922 int apply_parse_options(int argc, const char **argv,
4923                         struct apply_state *state,
4924                         int *force_apply, int *options,
4925                         const char * const *apply_usage)
4926 {
4927         struct option builtin_apply_options[] = {
4928                 { OPTION_CALLBACK, 0, "exclude", state, N_("path"),
4929                         N_("don't apply changes matching the given path"),
4930                         0, apply_option_parse_exclude },
4931                 { OPTION_CALLBACK, 0, "include", state, N_("path"),
4932                         N_("apply changes matching the given path"),
4933                         0, apply_option_parse_include },
4934                 { OPTION_CALLBACK, 'p', NULL, state, N_("num"),
4935                         N_("remove <num> leading slashes from traditional diff paths"),
4936                         0, apply_option_parse_p },
4937                 OPT_BOOL(0, "no-add", &state->no_add,
4938                         N_("ignore additions made by the patch")),
4939                 OPT_BOOL(0, "stat", &state->diffstat,
4940                         N_("instead of applying the patch, output diffstat for the input")),
4941                 OPT_NOOP_NOARG(0, "allow-binary-replacement"),
4942                 OPT_NOOP_NOARG(0, "binary"),
4943                 OPT_BOOL(0, "numstat", &state->numstat,
4944                         N_("show number of added and deleted lines in decimal notation")),
4945                 OPT_BOOL(0, "summary", &state->summary,
4946                         N_("instead of applying the patch, output a summary for the input")),
4947                 OPT_BOOL(0, "check", &state->check,
4948                         N_("instead of applying the patch, see if the patch is applicable")),
4949                 OPT_BOOL(0, "index", &state->check_index,
4950                         N_("make sure the patch is applicable to the current index")),
4951                 OPT_BOOL(0, "cached", &state->cached,
4952                         N_("apply a patch without touching the working tree")),
4953                 OPT_BOOL(0, "unsafe-paths", &state->unsafe_paths,
4954                         N_("accept a patch that touches outside the working area")),
4955                 OPT_BOOL(0, "apply", force_apply,
4956                         N_("also apply the patch (use with --stat/--summary/--check)")),
4957                 OPT_BOOL('3', "3way", &state->threeway,
4958                          N_( "attempt three-way merge if a patch does not apply")),
4959                 OPT_FILENAME(0, "build-fake-ancestor", &state->fake_ancestor,
4960                         N_("build a temporary index based on embedded index information")),
4961                 /* Think twice before adding "--nul" synonym to this */
4962                 OPT_SET_INT('z', NULL, &state->line_termination,
4963                         N_("paths are separated with NUL character"), '\0'),
4964                 OPT_INTEGER('C', NULL, &state->p_context,
4965                                 N_("ensure at least <n> lines of context match")),
4966                 { OPTION_CALLBACK, 0, "whitespace", state, N_("action"),
4967                         N_("detect new or modified lines that have whitespace errors"),
4968                         0, apply_option_parse_whitespace },
4969                 { OPTION_CALLBACK, 0, "ignore-space-change", state, NULL,
4970                         N_("ignore changes in whitespace when finding context"),
4971                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4972                 { OPTION_CALLBACK, 0, "ignore-whitespace", state, NULL,
4973                         N_("ignore changes in whitespace when finding context"),
4974                         PARSE_OPT_NOARG, apply_option_parse_space_change },
4975                 OPT_BOOL('R', "reverse", &state->apply_in_reverse,
4976                         N_("apply the patch in reverse")),
4977                 OPT_BOOL(0, "unidiff-zero", &state->unidiff_zero,
4978                         N_("don't expect at least one line of context")),
4979                 OPT_BOOL(0, "reject", &state->apply_with_reject,
4980                         N_("leave the rejected hunks in corresponding *.rej files")),
4981                 OPT_BOOL(0, "allow-overlap", &state->allow_overlap,
4982                         N_("allow overlapping hunks")),
4983                 OPT__VERBOSE(&state->apply_verbosity, N_("be verbose")),
4984                 OPT_BIT(0, "inaccurate-eof", options,
4985                         N_("tolerate incorrectly detected missing new-line at the end of file"),
4986                         APPLY_OPT_INACCURATE_EOF),
4987                 OPT_BIT(0, "recount", options,
4988                         N_("do not trust the line counts in the hunk headers"),
4989                         APPLY_OPT_RECOUNT),
4990                 { OPTION_CALLBACK, 0, "directory", state, N_("root"),
4991                         N_("prepend <root> to all filenames"),
4992                         0, apply_option_parse_directory },
4993                 OPT_END()
4994         };
4995
4996         return parse_options(argc, argv, state->prefix, builtin_apply_options, apply_usage, 0);
4997 }