builtin/am.c

   1 /*
   2  * Builtin "git am"
   3  *
   4  * Based on git-am.sh by Junio C Hamano.
   5  */
   6 #define USE_THE_INDEX_COMPATIBILITY_MACROS
   7 #include "cache.h"
   8 #include "config.h"
   9 #include "builtin.h"
  10 #include "exec-cmd.h"
  11 #include "parse-options.h"
  12 #include "dir.h"
  13 #include "run-command.h"
  14 #include "quote.h"
  15 #include "tempfile.h"
  16 #include "lockfile.h"
  17 #include "cache-tree.h"
  18 #include "refs.h"
  19 #include "commit.h"
  20 #include "diff.h"
  21 #include "diffcore.h"
  22 #include "unpack-trees.h"
  23 #include "branch.h"
  24 #include "sequencer.h"
  25 #include "revision.h"
  26 #include "merge-recursive.h"
  27 #include "log-tree.h"
  28 #include "notes-utils.h"
  29 #include "rerere.h"
  30 #include "prompt.h"
  31 #include "mailinfo.h"
  32 #include "apply.h"
  33 #include "string-list.h"
  34 #include "packfile.h"
  35 #include "repository.h"
  36
  37 /**
  38  * Returns the length of the first line of msg.
  39  */
  40 static int linelen(const char *msg)
  41 {
  42         return strchrnul(msg, '\n') - msg;
  43 }
  44
  45 /**
  46  * Returns true if `str` consists of only whitespace, false otherwise.
  47  */
  48 static int str_isspace(const char *str)
  49 {
  50         for (; *str; str++)
  51                 if (!isspace(*str))
  52                         return 0;
  53
  54         return 1;
  55 }
  56
  57 enum patch_format {
  58         PATCH_FORMAT_UNKNOWN = 0,
  59         PATCH_FORMAT_MBOX,
  60         PATCH_FORMAT_STGIT,
  61         PATCH_FORMAT_STGIT_SERIES,
  62         PATCH_FORMAT_HG,
  63         PATCH_FORMAT_MBOXRD
  64 };
  65
  66 enum keep_type {
  67         KEEP_FALSE = 0,
  68         KEEP_TRUE,      /* pass -k flag to git-mailinfo */
  69         KEEP_NON_PATCH  /* pass -b flag to git-mailinfo */
  70 };
  71
  72 enum scissors_type {
  73         SCISSORS_UNSET = -1,
  74         SCISSORS_FALSE = 0,  /* pass --no-scissors to git-mailinfo */
  75         SCISSORS_TRUE        /* pass --scissors to git-mailinfo */
  76 };
  77
  78 enum signoff_type {
  79         SIGNOFF_FALSE = 0,
  80         SIGNOFF_TRUE = 1,
  81         SIGNOFF_EXPLICIT /* --signoff was set on the command-line */
  82 };
  83
  84 enum show_patch_type {
  85         SHOW_PATCH_RAW = 0,
  86         SHOW_PATCH_DIFF = 1,
  87 };
  88
  89 struct am_state {
  90         /* state directory path */
  91         char *dir;
  92
  93         /* current and last patch numbers, 1-indexed */
  94         int cur;
  95         int last;
  96
  97         /* commit metadata and message */
  98         char *author_name;
  99         char *author_email;
 100         char *author_date;
 101         char *msg;
 102         size_t msg_len;
 103
 104         /* when --rebasing, records the original commit the patch came from */
 105         struct object_id orig_commit;
 106
 107         /* number of digits in patch filename */
 108         int prec;
 109
 110         /* various operating modes and command line options */
 111         int interactive;
 112         int threeway;
 113         int quiet;
 114         int signoff; /* enum signoff_type */
 115         int utf8;
 116         int keep; /* enum keep_type */
 117         int message_id;
 118         int scissors; /* enum scissors_type */
 119         struct argv_array git_apply_opts;
 120         const char *resolvemsg;
 121         int committer_date_is_author_date;
 122         int ignore_date;
 123         int allow_rerere_autoupdate;
 124         const char *sign_commit;
 125         int rebasing;
 126 };
 127
 128 /**
 129  * Initializes am_state with the default values.
 130  */
 131 static void am_state_init(struct am_state *state)
 132 {
 133         int gpgsign;
 134
 135         memset(state, 0, sizeof(*state));
 136
 137         state->dir = git_pathdup("rebase-apply");
 138
 139         state->prec = 4;
 140
 141         git_config_get_bool("am.threeway", &state->threeway);
 142
 143         state->utf8 = 1;
 144
 145         git_config_get_bool("am.messageid", &state->message_id);
 146
 147         state->scissors = SCISSORS_UNSET;
 148
 149         argv_array_init(&state->git_apply_opts);
 150
 151         if (!git_config_get_bool("commit.gpgsign", &gpgsign))
 152                 state->sign_commit = gpgsign ? "" : NULL;
 153 }
 154
 155 /**
 156  * Releases memory allocated by an am_state.
 157  */
 158 static void am_state_release(struct am_state *state)
 159 {
 160         free(state->dir);
 161         free(state->author_name);
 162         free(state->author_email);
 163         free(state->author_date);
 164         free(state->msg);
 165         argv_array_clear(&state->git_apply_opts);
 166 }
 167
 168 /**
 169  * Returns path relative to the am_state directory.
 170  */
 171 static inline const char *am_path(const struct am_state *state, const char *path)
 172 {
 173         return mkpath("%s/%s", state->dir, path);
 174 }
 175
 176 /**
 177  * For convenience to call write_file()
 178  */
 179 static void write_state_text(const struct am_state *state,
 180                              const char *name, const char *string)
 181 {
 182         write_file(am_path(state, name), "%s", string);
 183 }
 184
 185 static void write_state_count(const struct am_state *state,
 186                               const char *name, int value)
 187 {
 188         write_file(am_path(state, name), "%d", value);
 189 }
 190
 191 static void write_state_bool(const struct am_state *state,
 192                              const char *name, int value)
 193 {
 194         write_state_text(state, name, value ? "t" : "f");
 195 }
 196
 197 /**
 198  * If state->quiet is false, calls fprintf(fp, fmt, ...), and appends a newline
 199  * at the end.
 200  */
 201 static void say(const struct am_state *state, FILE *fp, const char *fmt, ...)
 202 {
 203         va_list ap;
 204
 205         va_start(ap, fmt);
 206         if (!state->quiet) {
 207                 vfprintf(fp, fmt, ap);
 208                 putc('\n', fp);
 209         }
 210         va_end(ap);
 211 }
 212
 213 /**
 214  * Returns 1 if there is an am session in progress, 0 otherwise.
 215  */
 216 static int am_in_progress(const struct am_state *state)
 217 {
 218         struct stat st;
 219
 220         if (lstat(state->dir, &st) < 0 || !S_ISDIR(st.st_mode))
 221                 return 0;
 222         if (lstat(am_path(state, "last"), &st) || !S_ISREG(st.st_mode))
 223                 return 0;
 224         if (lstat(am_path(state, "next"), &st) || !S_ISREG(st.st_mode))
 225                 return 0;
 226         return 1;
 227 }
 228
 229 /**
 230  * Reads the contents of `file` in the `state` directory into `sb`. Returns the
 231  * number of bytes read on success, -1 if the file does not exist. If `trim` is
 232  * set, trailing whitespace will be removed.
 233  */
 234 static int read_state_file(struct strbuf *sb, const struct am_state *state,
 235                         const char *file, int trim)
 236 {
 237         strbuf_reset(sb);
 238
 239         if (strbuf_read_file(sb, am_path(state, file), 0) >= 0) {
 240                 if (trim)
 241                         strbuf_trim(sb);
 242
 243                 return sb->len;
 244         }
 245
 246         if (errno == ENOENT)
 247                 return -1;
 248
 249         die_errno(_("could not read '%s'"), am_path(state, file));
 250 }
 251
 252 /**
 253  * Reads and parses the state directory's "author-script" file, and sets
 254  * state->author_name, state->author_email and state->author_date accordingly.
 255  * Returns 0 on success, -1 if the file could not be parsed.
 256  *
 257  * The author script is of the format:
 258  *
 259  *      GIT_AUTHOR_NAME='$author_name'
 260  *      GIT_AUTHOR_EMAIL='$author_email'
 261  *      GIT_AUTHOR_DATE='$author_date'
 262  *
 263  * where $author_name, $author_email and $author_date are quoted. We are strict
 264  * with our parsing, as the file was meant to be eval'd in the old git-am.sh
 265  * script, and thus if the file differs from what this function expects, it is
 266  * better to bail out than to do something that the user does not expect.
 267  */
 268 static int read_am_author_script(struct am_state *state)
 269 {
 270         const char *filename = am_path(state, "author-script");
 271
 272         assert(!state->author_name);
 273         assert(!state->author_email);
 274         assert(!state->author_date);
 275
 276         return read_author_script(filename, &state->author_name,
 277                                   &state->author_email, &state->author_date, 1);
 278 }
 279
 280 /**
 281  * Saves state->author_name, state->author_email and state->author_date in the
 282  * state directory's "author-script" file.
 283  */
 284 static void write_author_script(const struct am_state *state)
 285 {
 286         struct strbuf sb = STRBUF_INIT;
 287
 288         strbuf_addstr(&sb, "GIT_AUTHOR_NAME=");
 289         sq_quote_buf(&sb, state->author_name);
 290         strbuf_addch(&sb, '\n');
 291
 292         strbuf_addstr(&sb, "GIT_AUTHOR_EMAIL=");
 293         sq_quote_buf(&sb, state->author_email);
 294         strbuf_addch(&sb, '\n');
 295
 296         strbuf_addstr(&sb, "GIT_AUTHOR_DATE=");
 297         sq_quote_buf(&sb, state->author_date);
 298         strbuf_addch(&sb, '\n');
 299
 300         write_state_text(state, "author-script", sb.buf);
 301
 302         strbuf_release(&sb);
 303 }
 304
 305 /**
 306  * Reads the commit message from the state directory's "final-commit" file,
 307  * setting state->msg to its contents and state->msg_len to the length of its
 308  * contents in bytes.
 309  *
 310  * Returns 0 on success, -1 if the file does not exist.
 311  */
 312 static int read_commit_msg(struct am_state *state)
 313 {
 314         struct strbuf sb = STRBUF_INIT;
 315
 316         assert(!state->msg);
 317
 318         if (read_state_file(&sb, state, "final-commit", 0) < 0) {
 319                 strbuf_release(&sb);
 320                 return -1;
 321         }
 322
 323         state->msg = strbuf_detach(&sb, &state->msg_len);
 324         return 0;
 325 }
 326
 327 /**
 328  * Saves state->msg in the state directory's "final-commit" file.
 329  */
 330 static void write_commit_msg(const struct am_state *state)
 331 {
 332         const char *filename = am_path(state, "final-commit");
 333         write_file_buf(filename, state->msg, state->msg_len);
 334 }
 335
 336 /**
 337  * Loads state from disk.
 338  */
 339 static void am_load(struct am_state *state)
 340 {
 341         struct strbuf sb = STRBUF_INIT;
 342
 343         if (read_state_file(&sb, state, "next", 1) < 0)
 344                 BUG("state file 'next' does not exist");
 345         state->cur = strtol(sb.buf, NULL, 10);
 346
 347         if (read_state_file(&sb, state, "last", 1) < 0)
 348                 BUG("state file 'last' does not exist");
 349         state->last = strtol(sb.buf, NULL, 10);
 350
 351         if (read_am_author_script(state) < 0)
 352                 die(_("could not parse author script"));
 353
 354         read_commit_msg(state);
 355
 356         if (read_state_file(&sb, state, "original-commit", 1) < 0)
 357                 oidclr(&state->orig_commit);
 358         else if (get_oid_hex(sb.buf, &state->orig_commit) < 0)
 359                 die(_("could not parse %s"), am_path(state, "original-commit"));
 360
 361         read_state_file(&sb, state, "threeway", 1);
 362         state->threeway = !strcmp(sb.buf, "t");
 363
 364         read_state_file(&sb, state, "quiet", 1);
 365         state->quiet = !strcmp(sb.buf, "t");
 366
 367         read_state_file(&sb, state, "sign", 1);
 368         state->signoff = !strcmp(sb.buf, "t");
 369
 370         read_state_file(&sb, state, "utf8", 1);
 371         state->utf8 = !strcmp(sb.buf, "t");
 372
 373         if (file_exists(am_path(state, "rerere-autoupdate"))) {
 374                 read_state_file(&sb, state, "rerere-autoupdate", 1);
 375                 state->allow_rerere_autoupdate = strcmp(sb.buf, "t") ?
 376                         RERERE_NOAUTOUPDATE : RERERE_AUTOUPDATE;
 377         } else {
 378                 state->allow_rerere_autoupdate = 0;
 379         }
 380
 381         read_state_file(&sb, state, "keep", 1);
 382         if (!strcmp(sb.buf, "t"))
 383                 state->keep = KEEP_TRUE;
 384         else if (!strcmp(sb.buf, "b"))
 385                 state->keep = KEEP_NON_PATCH;
 386         else
 387                 state->keep = KEEP_FALSE;
 388
 389         read_state_file(&sb, state, "messageid", 1);
 390         state->message_id = !strcmp(sb.buf, "t");
 391
 392         read_state_file(&sb, state, "scissors", 1);
 393         if (!strcmp(sb.buf, "t"))
 394                 state->scissors = SCISSORS_TRUE;
 395         else if (!strcmp(sb.buf, "f"))
 396                 state->scissors = SCISSORS_FALSE;
 397         else
 398                 state->scissors = SCISSORS_UNSET;
 399
 400         read_state_file(&sb, state, "apply-opt", 1);
 401         argv_array_clear(&state->git_apply_opts);
 402         if (sq_dequote_to_argv_array(sb.buf, &state->git_apply_opts) < 0)
 403                 die(_("could not parse %s"), am_path(state, "apply-opt"));
 404
 405         state->rebasing = !!file_exists(am_path(state, "rebasing"));
 406
 407         strbuf_release(&sb);
 408 }
 409
 410 /**
 411  * Removes the am_state directory, forcefully terminating the current am
 412  * session.
 413  */
 414 static void am_destroy(const struct am_state *state)
 415 {
 416         struct strbuf sb = STRBUF_INIT;
 417
 418         strbuf_addstr(&sb, state->dir);
 419         remove_dir_recursively(&sb, 0);
 420         strbuf_release(&sb);
 421 }
 422
 423 /**
 424  * Runs applypatch-msg hook. Returns its exit code.
 425  */
 426 static int run_applypatch_msg_hook(struct am_state *state)
 427 {
 428         int ret;
 429
 430         assert(state->msg);
 431         ret = run_hook_le(NULL, "applypatch-msg", am_path(state, "final-commit"), NULL);
 432
 433         if (!ret) {
 434                 FREE_AND_NULL(state->msg);
 435                 if (read_commit_msg(state) < 0)
 436                         die(_("'%s' was deleted by the applypatch-msg hook"),
 437                                 am_path(state, "final-commit"));
 438         }
 439
 440         return ret;
 441 }
 442
 443 /**
 444  * Runs post-rewrite hook. Returns it exit code.
 445  */
 446 static int run_post_rewrite_hook(const struct am_state *state)
 447 {
 448         struct child_process cp = CHILD_PROCESS_INIT;
 449         const char *hook = find_hook("post-rewrite");
 450         int ret;
 451
 452         if (!hook)
 453                 return 0;
 454
 455         argv_array_push(&cp.args, hook);
 456         argv_array_push(&cp.args, "rebase");
 457
 458         cp.in = xopen(am_path(state, "rewritten"), O_RDONLY);
 459         cp.stdout_to_stderr = 1;
 460         cp.trace2_hook_name = "post-rewrite";
 461
 462         ret = run_command(&cp);
 463
 464         close(cp.in);
 465         return ret;
 466 }
 467
 468 /**
 469  * Reads the state directory's "rewritten" file, and copies notes from the old
 470  * commits listed in the file to their rewritten commits.
 471  *
 472  * Returns 0 on success, -1 on failure.
 473  */
 474 static int copy_notes_for_rebase(const struct am_state *state)
 475 {
 476         struct notes_rewrite_cfg *c;
 477         struct strbuf sb = STRBUF_INIT;
 478         const char *invalid_line = _("Malformed input line: '%s'.");
 479         const char *msg = "Notes added by 'git rebase'";
 480         FILE *fp;
 481         int ret = 0;
 482
 483         assert(state->rebasing);
 484
 485         c = init_copy_notes_for_rewrite("rebase");
 486         if (!c)
 487                 return 0;
 488
 489         fp = xfopen(am_path(state, "rewritten"), "r");
 490
 491         while (!strbuf_getline_lf(&sb, fp)) {
 492                 struct object_id from_obj, to_obj;
 493                 const char *p;
 494
 495                 if (sb.len != the_hash_algo->hexsz * 2 + 1) {
 496                         ret = error(invalid_line, sb.buf);
 497                         goto finish;
 498                 }
 499
 500                 if (parse_oid_hex(sb.buf, &from_obj, &p)) {
 501                         ret = error(invalid_line, sb.buf);
 502                         goto finish;
 503                 }
 504
 505                 if (*p != ' ') {
 506                         ret = error(invalid_line, sb.buf);
 507                         goto finish;
 508                 }
 509
 510                 if (get_oid_hex(p + 1, &to_obj)) {
 511                         ret = error(invalid_line, sb.buf);
 512                         goto finish;
 513                 }
 514
 515                 if (copy_note_for_rewrite(c, &from_obj, &to_obj))
 516                         ret = error(_("Failed to copy notes from '%s' to '%s'"),
 517                                         oid_to_hex(&from_obj), oid_to_hex(&to_obj));
 518         }
 519
 520 finish:
 521         finish_copy_notes_for_rewrite(the_repository, c, msg);
 522         fclose(fp);
 523         strbuf_release(&sb);
 524         return ret;
 525 }
 526
 527 /**
 528  * Determines if the file looks like a piece of RFC2822 mail by grabbing all
 529  * non-indented lines and checking if they look like they begin with valid
 530  * header field names.
 531  *
 532  * Returns 1 if the file looks like a piece of mail, 0 otherwise.
 533  */
 534 static int is_mail(FILE *fp)
 535 {
 536         const char *header_regex = "^[!-9;-~]+:";
 537         struct strbuf sb = STRBUF_INIT;
 538         regex_t regex;
 539         int ret = 1;
 540
 541         if (fseek(fp, 0L, SEEK_SET))
 542                 die_errno(_("fseek failed"));
 543
 544         if (regcomp(&regex, header_regex, REG_NOSUB | REG_EXTENDED))
 545                 die("invalid pattern: %s", header_regex);
 546
 547         while (!strbuf_getline(&sb, fp)) {
 548                 if (!sb.len)
 549                         break; /* End of header */
 550
 551                 /* Ignore indented folded lines */
 552                 if (*sb.buf == '\t' || *sb.buf == ' ')
 553                         continue;
 554
 555                 /* It's a header if it matches header_regex */
 556                 if (regexec(&regex, sb.buf, 0, NULL, 0)) {
 557                         ret = 0;
 558                         goto done;
 559                 }
 560         }
 561
 562 done:
 563         regfree(&regex);
 564         strbuf_release(&sb);
 565         return ret;
 566 }
 567
 568 /**
 569  * Attempts to detect the patch_format of the patches contained in `paths`,
 570  * returning the PATCH_FORMAT_* enum value. Returns PATCH_FORMAT_UNKNOWN if
 571  * detection fails.
 572  */
 573 static int detect_patch_format(const char **paths)
 574 {
 575         enum patch_format ret = PATCH_FORMAT_UNKNOWN;
 576         struct strbuf l1 = STRBUF_INIT;
 577         struct strbuf l2 = STRBUF_INIT;
 578         struct strbuf l3 = STRBUF_INIT;
 579         FILE *fp;
 580
 581         /*
 582          * We default to mbox format if input is from stdin and for directories
 583          */
 584         if (!*paths || !strcmp(*paths, "-") || is_directory(*paths))
 585                 return PATCH_FORMAT_MBOX;
 586
 587         /*
 588          * Otherwise, check the first few lines of the first patch, starting
 589          * from the first non-blank line, to try to detect its format.
 590          */
 591
 592         fp = xfopen(*paths, "r");
 593
 594         while (!strbuf_getline(&l1, fp)) {
 595                 if (l1.len)
 596                         break;
 597         }
 598
 599         if (starts_with(l1.buf, "From ") || starts_with(l1.buf, "From: ")) {
 600                 ret = PATCH_FORMAT_MBOX;
 601                 goto done;
 602         }
 603
 604         if (starts_with(l1.buf, "# This series applies on GIT commit")) {
 605                 ret = PATCH_FORMAT_STGIT_SERIES;
 606                 goto done;
 607         }
 608
 609         if (!strcmp(l1.buf, "# HG changeset patch")) {
 610                 ret = PATCH_FORMAT_HG;
 611                 goto done;
 612         }
 613
 614         strbuf_getline(&l2, fp);
 615         strbuf_getline(&l3, fp);
 616
 617         /*
 618          * If the second line is empty and the third is a From, Author or Date
 619          * entry, this is likely an StGit patch.
 620          */
 621         if (l1.len && !l2.len &&
 622                 (starts_with(l3.buf, "From:") ||
 623                  starts_with(l3.buf, "Author:") ||
 624                  starts_with(l3.buf, "Date:"))) {
 625                 ret = PATCH_FORMAT_STGIT;
 626                 goto done;
 627         }
 628
 629         if (l1.len && is_mail(fp)) {
 630                 ret = PATCH_FORMAT_MBOX;
 631                 goto done;
 632         }
 633
 634 done:
 635         fclose(fp);
 636         strbuf_release(&l1);
 637         strbuf_release(&l2);
 638         strbuf_release(&l3);
 639         return ret;
 640 }
 641
 642 /**
 643  * Splits out individual email patches from `paths`, where each path is either
 644  * a mbox file or a Maildir. Returns 0 on success, -1 on failure.
 645  */
 646 static int split_mail_mbox(struct am_state *state, const char **paths,
 647                                 int keep_cr, int mboxrd)
 648 {
 649         struct child_process cp = CHILD_PROCESS_INIT;
 650         struct strbuf last = STRBUF_INIT;
 651         int ret;
 652
 653         cp.git_cmd = 1;
 654         argv_array_push(&cp.args, "mailsplit");
 655         argv_array_pushf(&cp.args, "-d%d", state->prec);
 656         argv_array_pushf(&cp.args, "-o%s", state->dir);
 657         argv_array_push(&cp.args, "-b");
 658         if (keep_cr)
 659                 argv_array_push(&cp.args, "--keep-cr");
 660         if (mboxrd)
 661                 argv_array_push(&cp.args, "--mboxrd");
 662         argv_array_push(&cp.args, "--");
 663         argv_array_pushv(&cp.args, paths);
 664
 665         ret = capture_command(&cp, &last, 8);
 666         if (ret)
 667                 goto exit;
 668
 669         state->cur = 1;
 670         state->last = strtol(last.buf, NULL, 10);
 671
 672 exit:
 673         strbuf_release(&last);
 674         return ret ? -1 : 0;
 675 }
 676
 677 /**
 678  * Callback signature for split_mail_conv(). The foreign patch should be
 679  * read from `in`, and the converted patch (in RFC2822 mail format) should be
 680  * written to `out`. Return 0 on success, or -1 on failure.
 681  */
 682 typedef int (*mail_conv_fn)(FILE *out, FILE *in, int keep_cr);
 683
 684 /**
 685  * Calls `fn` for each file in `paths` to convert the foreign patch to the
 686  * RFC2822 mail format suitable for parsing with git-mailinfo.
 687  *
 688  * Returns 0 on success, -1 on failure.
 689  */
 690 static int split_mail_conv(mail_conv_fn fn, struct am_state *state,
 691                         const char **paths, int keep_cr)
 692 {
 693         static const char *stdin_only[] = {"-", NULL};
 694         int i;
 695
 696         if (!*paths)
 697                 paths = stdin_only;
 698
 699         for (i = 0; *paths; paths++, i++) {
 700                 FILE *in, *out;
 701                 const char *mail;
 702                 int ret;
 703
 704                 if (!strcmp(*paths, "-"))
 705                         in = stdin;
 706                 else
 707                         in = fopen(*paths, "r");
 708
 709                 if (!in)
 710                         return error_errno(_("could not open '%s' for reading"),
 711                                            *paths);
 712
 713                 mail = mkpath("%s/%0*d", state->dir, state->prec, i + 1);
 714
 715                 out = fopen(mail, "w");
 716                 if (!out) {
 717                         if (in != stdin)
 718                                 fclose(in);
 719                         return error_errno(_("could not open '%s' for writing"),
 720                                            mail);
 721                 }
 722
 723                 ret = fn(out, in, keep_cr);
 724
 725                 fclose(out);
 726                 if (in != stdin)
 727                         fclose(in);
 728
 729                 if (ret)
 730                         return error(_("could not parse patch '%s'"), *paths);
 731         }
 732
 733         state->cur = 1;
 734         state->last = i;
 735         return 0;
 736 }
 737
 738 /**
 739  * A split_mail_conv() callback that converts an StGit patch to an RFC2822
 740  * message suitable for parsing with git-mailinfo.
 741  */
 742 static int stgit_patch_to_mail(FILE *out, FILE *in, int keep_cr)
 743 {
 744         struct strbuf sb = STRBUF_INIT;
 745         int subject_printed = 0;
 746
 747         while (!strbuf_getline_lf(&sb, in)) {
 748                 const char *str;
 749
 750                 if (str_isspace(sb.buf))
 751                         continue;
 752                 else if (skip_prefix(sb.buf, "Author:", &str))
 753                         fprintf(out, "From:%s\n", str);
 754                 else if (starts_with(sb.buf, "From") || starts_with(sb.buf, "Date"))
 755                         fprintf(out, "%s\n", sb.buf);
 756                 else if (!subject_printed) {
 757                         fprintf(out, "Subject: %s\n", sb.buf);
 758                         subject_printed = 1;
 759                 } else {
 760                         fprintf(out, "\n%s\n", sb.buf);
 761                         break;
 762                 }
 763         }
 764
 765         strbuf_reset(&sb);
 766         while (strbuf_fread(&sb, 8192, in) > 0) {
 767                 fwrite(sb.buf, 1, sb.len, out);
 768                 strbuf_reset(&sb);
 769         }
 770
 771         strbuf_release(&sb);
 772         return 0;
 773 }
 774
 775 /**
 776  * This function only supports a single StGit series file in `paths`.
 777  *
 778  * Given an StGit series file, converts the StGit patches in the series into
 779  * RFC2822 messages suitable for parsing with git-mailinfo, and queues them in
 780  * the state directory.
 781  *
 782  * Returns 0 on success, -1 on failure.
 783  */
 784 static int split_mail_stgit_series(struct am_state *state, const char **paths,
 785                                         int keep_cr)
 786 {
 787         const char *series_dir;
 788         char *series_dir_buf;
 789         FILE *fp;
 790         struct argv_array patches = ARGV_ARRAY_INIT;
 791         struct strbuf sb = STRBUF_INIT;
 792         int ret;
 793
 794         if (!paths[0] || paths[1])
 795                 return error(_("Only one StGIT patch series can be applied at once"));
 796
 797         series_dir_buf = xstrdup(*paths);
 798         series_dir = dirname(series_dir_buf);
 799
 800         fp = fopen(*paths, "r");
 801         if (!fp)
 802                 return error_errno(_("could not open '%s' for reading"), *paths);
 803
 804         while (!strbuf_getline_lf(&sb, fp)) {
 805                 if (*sb.buf == '#')
 806                         continue; /* skip comment lines */
 807
 808                 argv_array_push(&patches, mkpath("%s/%s", series_dir, sb.buf));
 809         }
 810
 811         fclose(fp);
 812         strbuf_release(&sb);
 813         free(series_dir_buf);
 814
 815         ret = split_mail_conv(stgit_patch_to_mail, state, patches.argv, keep_cr);
 816
 817         argv_array_clear(&patches);
 818         return ret;
 819 }
 820
 821 /**
 822  * A split_patches_conv() callback that converts a mercurial patch to a RFC2822
 823  * message suitable for parsing with git-mailinfo.
 824  */
 825 static int hg_patch_to_mail(FILE *out, FILE *in, int keep_cr)
 826 {
 827         struct strbuf sb = STRBUF_INIT;
 828         int rc = 0;
 829
 830         while (!strbuf_getline_lf(&sb, in)) {
 831                 const char *str;
 832
 833                 if (skip_prefix(sb.buf, "# User ", &str))
 834                         fprintf(out, "From: %s\n", str);
 835                 else if (skip_prefix(sb.buf, "# Date ", &str)) {
 836                         timestamp_t timestamp;
 837                         long tz, tz2;
 838                         char *end;
 839
 840                         errno = 0;
 841                         timestamp = parse_timestamp(str, &end, 10);
 842                         if (errno) {
 843                                 rc = error(_("invalid timestamp"));
 844                                 goto exit;
 845                         }
 846
 847                         if (!skip_prefix(end, " ", &str)) {
 848                                 rc = error(_("invalid Date line"));
 849                                 goto exit;
 850                         }
 851
 852                         errno = 0;
 853                         tz = strtol(str, &end, 10);
 854                         if (errno) {
 855                                 rc = error(_("invalid timezone offset"));
 856                                 goto exit;
 857                         }
 858
 859                         if (*end) {
 860                                 rc = error(_("invalid Date line"));
 861                                 goto exit;
 862                         }
 863
 864                         /*
 865                          * mercurial's timezone is in seconds west of UTC,
 866                          * however git's timezone is in hours + minutes east of
 867                          * UTC. Convert it.
 868                          */
 869                         tz2 = labs(tz) / 3600 * 100 + labs(tz) % 3600 / 60;
 870                         if (tz > 0)
 871                                 tz2 = -tz2;
 872
 873                         fprintf(out, "Date: %s\n", show_date(timestamp, tz2, DATE_MODE(RFC2822)));
 874                 } else if (starts_with(sb.buf, "# ")) {
 875                         continue;
 876                 } else {
 877                         fprintf(out, "\n%s\n", sb.buf);
 878                         break;
 879                 }
 880         }
 881
 882         strbuf_reset(&sb);
 883         while (strbuf_fread(&sb, 8192, in) > 0) {
 884                 fwrite(sb.buf, 1, sb.len, out);
 885                 strbuf_reset(&sb);
 886         }
 887 exit:
 888         strbuf_release(&sb);
 889         return rc;
 890 }
 891
 892 /**
 893  * Splits a list of files/directories into individual email patches. Each path
 894  * in `paths` must be a file/directory that is formatted according to
 895  * `patch_format`.
 896  *
 897  * Once split out, the individual email patches will be stored in the state
 898  * directory, with each patch's filename being its index, padded to state->prec
 899  * digits.
 900  *
 901  * state->cur will be set to the index of the first mail, and state->last will
 902  * be set to the index of the last mail.
 903  *
 904  * Set keep_cr to 0 to convert all lines ending with \r\n to end with \n, 1
 905  * to disable this behavior, -1 to use the default configured setting.
 906  *
 907  * Returns 0 on success, -1 on failure.
 908  */
 909 static int split_mail(struct am_state *state, enum patch_format patch_format,
 910                         const char **paths, int keep_cr)
 911 {
 912         if (keep_cr < 0) {
 913                 keep_cr = 0;
 914                 git_config_get_bool("am.keepcr", &keep_cr);
 915         }
 916
 917         switch (patch_format) {
 918         case PATCH_FORMAT_MBOX:
 919                 return split_mail_mbox(state, paths, keep_cr, 0);
 920         case PATCH_FORMAT_STGIT:
 921                 return split_mail_conv(stgit_patch_to_mail, state, paths, keep_cr);
 922         case PATCH_FORMAT_STGIT_SERIES:
 923                 return split_mail_stgit_series(state, paths, keep_cr);
 924         case PATCH_FORMAT_HG:
 925                 return split_mail_conv(hg_patch_to_mail, state, paths, keep_cr);
 926         case PATCH_FORMAT_MBOXRD:
 927                 return split_mail_mbox(state, paths, keep_cr, 1);
 928         default:
 929                 BUG("invalid patch_format");
 930         }
 931         return -1;
 932 }
 933
 934 /**
 935  * Setup a new am session for applying patches
 936  */
 937 static void am_setup(struct am_state *state, enum patch_format patch_format,
 938                         const char **paths, int keep_cr)
 939 {
 940         struct object_id curr_head;
 941         const char *str;
 942         struct strbuf sb = STRBUF_INIT;
 943
 944         if (!patch_format)
 945                 patch_format = detect_patch_format(paths);
 946
 947         if (!patch_format) {
 948                 fprintf_ln(stderr, _("Patch format detection failed."));
 949                 exit(128);
 950         }
 951
 952         if (mkdir(state->dir, 0777) < 0 && errno != EEXIST)
 953                 die_errno(_("failed to create directory '%s'"), state->dir);
 954         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
 955
 956         if (split_mail(state, patch_format, paths, keep_cr) < 0) {
 957                 am_destroy(state);
 958                 die(_("Failed to split patches."));
 959         }
 960
 961         if (state->rebasing)
 962                 state->threeway = 1;
 963
 964         write_state_bool(state, "threeway", state->threeway);
 965         write_state_bool(state, "quiet", state->quiet);
 966         write_state_bool(state, "sign", state->signoff);
 967         write_state_bool(state, "utf8", state->utf8);
 968
 969         if (state->allow_rerere_autoupdate)
 970                 write_state_bool(state, "rerere-autoupdate",
 971                          state->allow_rerere_autoupdate == RERERE_AUTOUPDATE);
 972
 973         switch (state->keep) {
 974         case KEEP_FALSE:
 975                 str = "f";
 976                 break;
 977         case KEEP_TRUE:
 978                 str = "t";
 979                 break;
 980         case KEEP_NON_PATCH:
 981                 str = "b";
 982                 break;
 983         default:
 984                 BUG("invalid value for state->keep");
 985         }
 986
 987         write_state_text(state, "keep", str);
 988         write_state_bool(state, "messageid", state->message_id);
 989
 990         switch (state->scissors) {
 991         case SCISSORS_UNSET:
 992                 str = "";
 993                 break;
 994         case SCISSORS_FALSE:
 995                 str = "f";
 996                 break;
 997         case SCISSORS_TRUE:
 998                 str = "t";
 999                 break;
1000         default:
1001                 BUG("invalid value for state->scissors");
1002         }
1003         write_state_text(state, "scissors", str);
1004
1005         sq_quote_argv(&sb, state->git_apply_opts.argv);
1006         write_state_text(state, "apply-opt", sb.buf);
1007
1008         if (state->rebasing)
1009                 write_state_text(state, "rebasing", "");
1010         else
1011                 write_state_text(state, "applying", "");
1012
1013         if (!get_oid("HEAD", &curr_head)) {
1014                 write_state_text(state, "abort-safety", oid_to_hex(&curr_head));
1015                 if (!state->rebasing)
1016                         update_ref("am", "ORIG_HEAD", &curr_head, NULL, 0,
1017                                    UPDATE_REFS_DIE_ON_ERR);
1018         } else {
1019                 write_state_text(state, "abort-safety", "");
1020                 if (!state->rebasing)
1021                         delete_ref(NULL, "ORIG_HEAD", NULL, 0);
1022         }
1023
1024         /*
1025          * NOTE: Since the "next" and "last" files determine if an am_state
1026          * session is in progress, they should be written last.
1027          */
1028
1029         write_state_count(state, "next", state->cur);
1030         write_state_count(state, "last", state->last);
1031
1032         strbuf_release(&sb);
1033 }
1034
1035 /**
1036  * Increments the patch pointer, and cleans am_state for the application of the
1037  * next patch.
1038  */
1039 static void am_next(struct am_state *state)
1040 {
1041         struct object_id head;
1042
1043         FREE_AND_NULL(state->author_name);
1044         FREE_AND_NULL(state->author_email);
1045         FREE_AND_NULL(state->author_date);
1046         FREE_AND_NULL(state->msg);
1047         state->msg_len = 0;
1048
1049         unlink(am_path(state, "author-script"));
1050         unlink(am_path(state, "final-commit"));
1051
1052         oidclr(&state->orig_commit);
1053         unlink(am_path(state, "original-commit"));
1054         delete_ref(NULL, "REBASE_HEAD", NULL, REF_NO_DEREF);
1055
1056         if (!get_oid("HEAD", &head))
1057                 write_state_text(state, "abort-safety", oid_to_hex(&head));
1058         else
1059                 write_state_text(state, "abort-safety", "");
1060
1061         state->cur++;
1062         write_state_count(state, "next", state->cur);
1063 }
1064
1065 /**
1066  * Returns the filename of the current patch email.
1067  */
1068 static const char *msgnum(const struct am_state *state)
1069 {
1070         static struct strbuf sb = STRBUF_INIT;
1071
1072         strbuf_reset(&sb);
1073         strbuf_addf(&sb, "%0*d", state->prec, state->cur);
1074
1075         return sb.buf;
1076 }
1077
1078 /**
1079  * Dies with a user-friendly message on how to proceed after resolving the
1080  * problem. This message can be overridden with state->resolvemsg.
1081  */
1082 static void NORETURN die_user_resolve(const struct am_state *state)
1083 {
1084         if (state->resolvemsg) {
1085                 printf_ln("%s", state->resolvemsg);
1086         } else {
1087                 const char *cmdline = state->interactive ? "git am -i" : "git am";
1088
1089                 printf_ln(_("When you have resolved this problem, run \"%s --continue\"."), cmdline);
1090                 printf_ln(_("If you prefer to skip this patch, run \"%s --skip\" instead."), cmdline);
1091                 printf_ln(_("To restore the original branch and stop patching, run \"%s --abort\"."), cmdline);
1092         }
1093
1094         exit(128);
1095 }
1096
1097 /**
1098  * Appends signoff to the "msg" field of the am_state.
1099  */
1100 static void am_append_signoff(struct am_state *state)
1101 {
1102         struct strbuf sb = STRBUF_INIT;
1103
1104         strbuf_attach(&sb, state->msg, state->msg_len, state->msg_len);
1105         append_signoff(&sb, 0, 0);
1106         state->msg = strbuf_detach(&sb, &state->msg_len);
1107 }
1108
1109 /**
1110  * Parses `mail` using git-mailinfo, extracting its patch and authorship info.
1111  * state->msg will be set to the patch message. state->author_name,
1112  * state->author_email and state->author_date will be set to the patch author's
1113  * name, email and date respectively. The patch body will be written to the
1114  * state directory's "patch" file.
1115  *
1116  * Returns 1 if the patch should be skipped, 0 otherwise.
1117  */
1118 static int parse_mail(struct am_state *state, const char *mail)
1119 {
1120         FILE *fp;
1121         struct strbuf sb = STRBUF_INIT;
1122         struct strbuf msg = STRBUF_INIT;
1123         struct strbuf author_name = STRBUF_INIT;
1124         struct strbuf author_date = STRBUF_INIT;
1125         struct strbuf author_email = STRBUF_INIT;
1126         int ret = 0;
1127         struct mailinfo mi;
1128
1129         setup_mailinfo(&mi);
1130
1131         if (state->utf8)
1132                 mi.metainfo_charset = get_commit_output_encoding();
1133         else
1134                 mi.metainfo_charset = NULL;
1135
1136         switch (state->keep) {
1137         case KEEP_FALSE:
1138                 break;
1139         case KEEP_TRUE:
1140                 mi.keep_subject = 1;
1141                 break;
1142         case KEEP_NON_PATCH:
1143                 mi.keep_non_patch_brackets_in_subject = 1;
1144                 break;
1145         default:
1146                 BUG("invalid value for state->keep");
1147         }
1148
1149         if (state->message_id)
1150                 mi.add_message_id = 1;
1151
1152         switch (state->scissors) {
1153         case SCISSORS_UNSET:
1154                 break;
1155         case SCISSORS_FALSE:
1156                 mi.use_scissors = 0;
1157                 break;
1158         case SCISSORS_TRUE:
1159                 mi.use_scissors = 1;
1160                 break;
1161         default:
1162                 BUG("invalid value for state->scissors");
1163         }
1164
1165         mi.input = xfopen(mail, "r");
1166         mi.output = xfopen(am_path(state, "info"), "w");
1167         if (mailinfo(&mi, am_path(state, "msg"), am_path(state, "patch")))
1168                 die("could not parse patch");
1169
1170         fclose(mi.input);
1171         fclose(mi.output);
1172
1173         if (mi.format_flowed)
1174                 warning(_("Patch sent with format=flowed; "
1175                           "space at the end of lines might be lost."));
1176
1177         /* Extract message and author information */
1178         fp = xfopen(am_path(state, "info"), "r");
1179         while (!strbuf_getline_lf(&sb, fp)) {
1180                 const char *x;
1181
1182                 if (skip_prefix(sb.buf, "Subject: ", &x)) {
1183                         if (msg.len)
1184                                 strbuf_addch(&msg, '\n');
1185                         strbuf_addstr(&msg, x);
1186                 } else if (skip_prefix(sb.buf, "Author: ", &x))
1187                         strbuf_addstr(&author_name, x);
1188                 else if (skip_prefix(sb.buf, "Email: ", &x))
1189                         strbuf_addstr(&author_email, x);
1190                 else if (skip_prefix(sb.buf, "Date: ", &x))
1191                         strbuf_addstr(&author_date, x);
1192         }
1193         fclose(fp);
1194
1195         /* Skip pine's internal folder data */
1196         if (!strcmp(author_name.buf, "Mail System Internal Data")) {
1197                 ret = 1;
1198                 goto finish;
1199         }
1200
1201         if (is_empty_or_missing_file(am_path(state, "patch"))) {
1202                 printf_ln(_("Patch is empty."));
1203                 die_user_resolve(state);
1204         }
1205
1206         strbuf_addstr(&msg, "\n\n");
1207         strbuf_addbuf(&msg, &mi.log_message);
1208         strbuf_stripspace(&msg, 0);
1209
1210         assert(!state->author_name);
1211         state->author_name = strbuf_detach(&author_name, NULL);
1212
1213         assert(!state->author_email);
1214         state->author_email = strbuf_detach(&author_email, NULL);
1215
1216         assert(!state->author_date);
1217         state->author_date = strbuf_detach(&author_date, NULL);
1218
1219         assert(!state->msg);
1220         state->msg = strbuf_detach(&msg, &state->msg_len);
1221
1222 finish:
1223         strbuf_release(&msg);
1224         strbuf_release(&author_date);
1225         strbuf_release(&author_email);
1226         strbuf_release(&author_name);
1227         strbuf_release(&sb);
1228         clear_mailinfo(&mi);
1229         return ret;
1230 }
1231
1232 /**
1233  * Sets commit_id to the commit hash where the mail was generated from.
1234  * Returns 0 on success, -1 on failure.
1235  */
1236 static int get_mail_commit_oid(struct object_id *commit_id, const char *mail)
1237 {
1238         struct strbuf sb = STRBUF_INIT;
1239         FILE *fp = xfopen(mail, "r");
1240         const char *x;
1241         int ret = 0;
1242
1243         if (strbuf_getline_lf(&sb, fp) ||
1244             !skip_prefix(sb.buf, "From ", &x) ||
1245             get_oid_hex(x, commit_id) < 0)
1246                 ret = -1;
1247
1248         strbuf_release(&sb);
1249         fclose(fp);
1250         return ret;
1251 }
1252
1253 /**
1254  * Sets state->msg, state->author_name, state->author_email, state->author_date
1255  * to the commit's respective info.
1256  */
1257 static void get_commit_info(struct am_state *state, struct commit *commit)
1258 {
1259         const char *buffer, *ident_line, *msg;
1260         size_t ident_len;
1261         struct ident_split id;
1262
1263         buffer = logmsg_reencode(commit, NULL, get_commit_output_encoding());
1264
1265         ident_line = find_commit_header(buffer, "author", &ident_len);
1266         if (!ident_line)
1267                 die(_("missing author line in commit %s"),
1268                       oid_to_hex(&commit->object.oid));
1269         if (split_ident_line(&id, ident_line, ident_len) < 0)
1270                 die(_("invalid ident line: %.*s"), (int)ident_len, ident_line);
1271
1272         assert(!state->author_name);
1273         if (id.name_begin)
1274                 state->author_name =
1275                         xmemdupz(id.name_begin, id.name_end - id.name_begin);
1276         else
1277                 state->author_name = xstrdup("");
1278
1279         assert(!state->author_email);
1280         if (id.mail_begin)
1281                 state->author_email =
1282                         xmemdupz(id.mail_begin, id.mail_end - id.mail_begin);
1283         else
1284                 state->author_email = xstrdup("");
1285
1286         assert(!state->author_date);
1287         state->author_date = xstrdup(show_ident_date(&id, DATE_MODE(NORMAL)));
1288
1289         assert(!state->msg);
1290         msg = strstr(buffer, "\n\n");
1291         if (!msg)
1292                 die(_("unable to parse commit %s"), oid_to_hex(&commit->object.oid));
1293         state->msg = xstrdup(msg + 2);
1294         state->msg_len = strlen(state->msg);
1295         unuse_commit_buffer(commit, buffer);
1296 }
1297
1298 /**
1299  * Writes `commit` as a patch to the state directory's "patch" file.
1300  */
1301 static void write_commit_patch(const struct am_state *state, struct commit *commit)
1302 {
1303         struct rev_info rev_info;
1304         FILE *fp;
1305
1306         fp = xfopen(am_path(state, "patch"), "w");
1307         repo_init_revisions(the_repository, &rev_info, NULL);
1308         rev_info.diff = 1;
1309         rev_info.abbrev = 0;
1310         rev_info.disable_stdin = 1;
1311         rev_info.show_root_diff = 1;
1312         rev_info.diffopt.output_format = DIFF_FORMAT_PATCH;
1313         rev_info.no_commit_id = 1;
1314         rev_info.diffopt.flags.binary = 1;
1315         rev_info.diffopt.flags.full_index = 1;
1316         rev_info.diffopt.use_color = 0;
1317         rev_info.diffopt.file = fp;
1318         rev_info.diffopt.close_file = 1;
1319         add_pending_object(&rev_info, &commit->object, "");
1320         diff_setup_done(&rev_info.diffopt);
1321         log_tree_commit(&rev_info, commit);
1322 }
1323
1324 /**
1325  * Writes the diff of the index against HEAD as a patch to the state
1326  * directory's "patch" file.
1327  */
1328 static void write_index_patch(const struct am_state *state)
1329 {
1330         struct tree *tree;
1331         struct object_id head;
1332         struct rev_info rev_info;
1333         FILE *fp;
1334
1335         if (!get_oid("HEAD", &head)) {
1336                 struct commit *commit = lookup_commit_or_die(&head, "HEAD");
1337                 tree = get_commit_tree(commit);
1338         } else
1339                 tree = lookup_tree(the_repository,
1340                                    the_repository->hash_algo->empty_tree);
1341
1342         fp = xfopen(am_path(state, "patch"), "w");
1343         repo_init_revisions(the_repository, &rev_info, NULL);
1344         rev_info.diff = 1;
1345         rev_info.disable_stdin = 1;
1346         rev_info.no_commit_id = 1;
1347         rev_info.diffopt.output_format = DIFF_FORMAT_PATCH;
1348         rev_info.diffopt.use_color = 0;
1349         rev_info.diffopt.file = fp;
1350         rev_info.diffopt.close_file = 1;
1351         add_pending_object(&rev_info, &tree->object, "");
1352         diff_setup_done(&rev_info.diffopt);
1353         run_diff_index(&rev_info, 1);
1354 }
1355
1356 /**
1357  * Like parse_mail(), but parses the mail by looking up its commit ID
1358  * directly. This is used in --rebasing mode to bypass git-mailinfo's munging
1359  * of patches.
1360  *
1361  * state->orig_commit will be set to the original commit ID.
1362  *
1363  * Will always return 0 as the patch should never be skipped.
1364  */
1365 static int parse_mail_rebase(struct am_state *state, const char *mail)
1366 {
1367         struct commit *commit;
1368         struct object_id commit_oid;
1369
1370         if (get_mail_commit_oid(&commit_oid, mail) < 0)
1371                 die(_("could not parse %s"), mail);
1372
1373         commit = lookup_commit_or_die(&commit_oid, mail);
1374
1375         get_commit_info(state, commit);
1376
1377         write_commit_patch(state, commit);
1378
1379         oidcpy(&state->orig_commit, &commit_oid);
1380         write_state_text(state, "original-commit", oid_to_hex(&commit_oid));
1381         update_ref("am", "REBASE_HEAD", &commit_oid,
1382                    NULL, REF_NO_DEREF, UPDATE_REFS_DIE_ON_ERR);
1383
1384         return 0;
1385 }
1386
1387 /**
1388  * Applies current patch with git-apply. Returns 0 on success, -1 otherwise. If
1389  * `index_file` is not NULL, the patch will be applied to that index.
1390  */
1391 static int run_apply(const struct am_state *state, const char *index_file)
1392 {
1393         struct argv_array apply_paths = ARGV_ARRAY_INIT;
1394         struct argv_array apply_opts = ARGV_ARRAY_INIT;
1395         struct apply_state apply_state;
1396         int res, opts_left;
1397         int force_apply = 0;
1398         int options = 0;
1399
1400         if (init_apply_state(&apply_state, the_repository, NULL))
1401                 BUG("init_apply_state() failed");
1402
1403         argv_array_push(&apply_opts, "apply");
1404         argv_array_pushv(&apply_opts, state->git_apply_opts.argv);
1405
1406         opts_left = apply_parse_options(apply_opts.argc, apply_opts.argv,
1407                                         &apply_state, &force_apply, &options,
1408                                         NULL);
1409
1410         if (opts_left != 0)
1411                 die("unknown option passed through to git apply");
1412
1413         if (index_file) {
1414                 apply_state.index_file = index_file;
1415                 apply_state.cached = 1;
1416         } else
1417                 apply_state.check_index = 1;
1418
1419         /*
1420          * If we are allowed to fall back on 3-way merge, don't give false
1421          * errors during the initial attempt.
1422          */
1423         if (state->threeway && !index_file)
1424                 apply_state.apply_verbosity = verbosity_silent;
1425
1426         if (check_apply_state(&apply_state, force_apply))
1427                 BUG("check_apply_state() failed");
1428
1429         argv_array_push(&apply_paths, am_path(state, "patch"));
1430
1431         res = apply_all_patches(&apply_state, apply_paths.argc, apply_paths.argv, options);
1432
1433         argv_array_clear(&apply_paths);
1434         argv_array_clear(&apply_opts);
1435         clear_apply_state(&apply_state);
1436
1437         if (res)
1438                 return res;
1439
1440         if (index_file) {
1441                 /* Reload index as apply_all_patches() will have modified it. */
1442                 discard_cache();
1443                 read_cache_from(index_file);
1444         }
1445
1446         return 0;
1447 }
1448
1449 /**
1450  * Builds an index that contains just the blobs needed for a 3way merge.
1451  */
1452 static int build_fake_ancestor(const struct am_state *state, const char *index_file)
1453 {
1454         struct child_process cp = CHILD_PROCESS_INIT;
1455
1456         cp.git_cmd = 1;
1457         argv_array_push(&cp.args, "apply");
1458         argv_array_pushv(&cp.args, state->git_apply_opts.argv);
1459         argv_array_pushf(&cp.args, "--build-fake-ancestor=%s", index_file);
1460         argv_array_push(&cp.args, am_path(state, "patch"));
1461
1462         if (run_command(&cp))
1463                 return -1;
1464
1465         return 0;
1466 }
1467
1468 /**
1469  * Attempt a threeway merge, using index_path as the temporary index.
1470  */
1471 static int fall_back_threeway(const struct am_state *state, const char *index_path)
1472 {
1473         struct object_id orig_tree, their_tree, our_tree;
1474         const struct object_id *bases[1] = { &orig_tree };
1475         struct merge_options o;
1476         struct commit *result;
1477         char *their_tree_name;
1478
1479         if (get_oid("HEAD", &our_tree) < 0)
1480                 oidcpy(&our_tree, the_hash_algo->empty_tree);
1481
1482         if (build_fake_ancestor(state, index_path))
1483                 return error("could not build fake ancestor");
1484
1485         discard_cache();
1486         read_cache_from(index_path);
1487
1488         if (write_index_as_tree(&orig_tree, &the_index, index_path, 0, NULL))
1489                 return error(_("Repository lacks necessary blobs to fall back on 3-way merge."));
1490
1491         say(state, stdout, _("Using index info to reconstruct a base tree..."));
1492
1493         if (!state->quiet) {
1494                 /*
1495                  * List paths that needed 3-way fallback, so that the user can
1496                  * review them with extra care to spot mismerges.
1497                  */
1498                 struct rev_info rev_info;
1499
1500                 repo_init_revisions(the_repository, &rev_info, NULL);
1501                 rev_info.diffopt.output_format = DIFF_FORMAT_NAME_STATUS;
1502                 rev_info.diffopt.filter |= diff_filter_bit('A');
1503                 rev_info.diffopt.filter |= diff_filter_bit('M');
1504                 add_pending_oid(&rev_info, "HEAD", &our_tree, 0);
1505                 diff_setup_done(&rev_info.diffopt);
1506                 run_diff_index(&rev_info, 1);
1507         }
1508
1509         if (run_apply(state, index_path))
1510                 return error(_("Did you hand edit your patch?\n"
1511                                 "It does not apply to blobs recorded in its index."));
1512
1513         if (write_index_as_tree(&their_tree, &the_index, index_path, 0, NULL))
1514                 return error("could not write tree");
1515
1516         say(state, stdout, _("Falling back to patching base and 3-way merge..."));
1517
1518         discard_cache();
1519         read_cache();
1520
1521         /*
1522          * This is not so wrong. Depending on which base we picked, orig_tree
1523          * may be wildly different from ours, but their_tree has the same set of
1524          * wildly different changes in parts the patch did not touch, so
1525          * recursive ends up canceling them, saying that we reverted all those
1526          * changes.
1527          */
1528
1529         init_merge_options(&o, the_repository);
1530
1531         o.branch1 = "HEAD";
1532         their_tree_name = xstrfmt("%.*s", linelen(state->msg), state->msg);
1533         o.branch2 = their_tree_name;
1534         o.detect_directory_renames = MERGE_DIRECTORY_RENAMES_NONE;
1535
1536         if (state->quiet)
1537                 o.verbosity = 0;
1538
1539         if (merge_recursive_generic(&o, &our_tree, &their_tree, 1, bases, &result)) {
1540                 repo_rerere(the_repository, state->allow_rerere_autoupdate);
1541                 free(their_tree_name);
1542                 return error(_("Failed to merge in the changes."));
1543         }
1544
1545         free(their_tree_name);
1546         return 0;
1547 }
1548
1549 /**
1550  * Commits the current index with state->msg as the commit message and
1551  * state->author_name, state->author_email and state->author_date as the author
1552  * information.
1553  */
1554 static void do_commit(const struct am_state *state)
1555 {
1556         struct object_id tree, parent, commit;
1557         const struct object_id *old_oid;
1558         struct commit_list *parents = NULL;
1559         const char *reflog_msg, *author;
1560         struct strbuf sb = STRBUF_INIT;
1561
1562         if (run_hook_le(NULL, "pre-applypatch", NULL))
1563                 exit(1);
1564
1565         if (write_cache_as_tree(&tree, 0, NULL))
1566                 die(_("git write-tree failed to write a tree"));
1567
1568         if (!get_oid_commit("HEAD", &parent)) {
1569                 old_oid = &parent;
1570                 commit_list_insert(lookup_commit(the_repository, &parent),
1571                                    &parents);
1572         } else {
1573                 old_oid = NULL;
1574                 say(state, stderr, _("applying to an empty history"));
1575         }
1576
1577         author = fmt_ident(state->author_name, state->author_email,
1578                 WANT_AUTHOR_IDENT,
1579                         state->ignore_date ? NULL : state->author_date,
1580                         IDENT_STRICT);
1581
1582         if (state->committer_date_is_author_date)
1583                 setenv("GIT_COMMITTER_DATE",
1584                         state->ignore_date ? "" : state->author_date, 1);
1585
1586         if (commit_tree(state->msg, state->msg_len, &tree, parents, &commit,
1587                         author, state->sign_commit))
1588                 die(_("failed to write commit object"));
1589
1590         reflog_msg = getenv("GIT_REFLOG_ACTION");
1591         if (!reflog_msg)
1592                 reflog_msg = "am";
1593
1594         strbuf_addf(&sb, "%s: %.*s", reflog_msg, linelen(state->msg),
1595                         state->msg);
1596
1597         update_ref(sb.buf, "HEAD", &commit, old_oid, 0,
1598                    UPDATE_REFS_DIE_ON_ERR);
1599
1600         if (state->rebasing) {
1601                 FILE *fp = xfopen(am_path(state, "rewritten"), "a");
1602
1603                 assert(!is_null_oid(&state->orig_commit));
1604                 fprintf(fp, "%s ", oid_to_hex(&state->orig_commit));
1605                 fprintf(fp, "%s\n", oid_to_hex(&commit));
1606                 fclose(fp);
1607         }
1608
1609         run_hook_le(NULL, "post-applypatch", NULL);
1610
1611         strbuf_release(&sb);
1612 }
1613
1614 /**
1615  * Validates the am_state for resuming -- the "msg" and authorship fields must
1616  * be filled up.
1617  */
1618 static void validate_resume_state(const struct am_state *state)
1619 {
1620         if (!state->msg)
1621                 die(_("cannot resume: %s does not exist."),
1622                         am_path(state, "final-commit"));
1623
1624         if (!state->author_name || !state->author_email || !state->author_date)
1625                 die(_("cannot resume: %s does not exist."),
1626                         am_path(state, "author-script"));
1627 }
1628
1629 /**
1630  * Interactively prompt the user on whether the current patch should be
1631  * applied.
1632  *
1633  * Returns 0 if the user chooses to apply the patch, 1 if the user chooses to
1634  * skip it.
1635  */
1636 static int do_interactive(struct am_state *state)
1637 {
1638         assert(state->msg);
1639
1640         for (;;) {
1641                 char reply[64];
1642
1643                 puts(_("Commit Body is:"));
1644                 puts("--------------------------");
1645                 printf("%s", state->msg);
1646                 puts("--------------------------");
1647
1648                 /*
1649                  * TRANSLATORS: Make sure to include [y], [n], [e], [v] and [a]
1650                  * in your translation. The program will only accept English
1651                  * input at this point.
1652                  */
1653                 printf(_("Apply? [y]es/[n]o/[e]dit/[v]iew patch/[a]ccept all: "));
1654                 if (!fgets(reply, sizeof(reply), stdin))
1655                         die("unable to read from stdin; aborting");
1656
1657                 if (*reply == 'y' || *reply == 'Y') {
1658                         return 0;
1659                 } else if (*reply == 'a' || *reply == 'A') {
1660                         state->interactive = 0;
1661                         return 0;
1662                 } else if (*reply == 'n' || *reply == 'N') {
1663                         return 1;
1664                 } else if (*reply == 'e' || *reply == 'E') {
1665                         struct strbuf msg = STRBUF_INIT;
1666
1667                         if (!launch_editor(am_path(state, "final-commit"), &msg, NULL)) {
1668                                 free(state->msg);
1669                                 state->msg = strbuf_detach(&msg, &state->msg_len);
1670                         }
1671                         strbuf_release(&msg);
1672                 } else if (*reply == 'v' || *reply == 'V') {
1673                         const char *pager = git_pager(1);
1674                         struct child_process cp = CHILD_PROCESS_INIT;
1675
1676                         if (!pager)
1677                                 pager = "cat";
1678                         prepare_pager_args(&cp, pager);
1679                         argv_array_push(&cp.args, am_path(state, "patch"));
1680                         run_command(&cp);
1681                 }
1682         }
1683 }
1684
1685 /**
1686  * Applies all queued mail.
1687  *
1688  * If `resume` is true, we are "resuming". The "msg" and authorship fields, as
1689  * well as the state directory's "patch" file is used as-is for applying the
1690  * patch and committing it.
1691  */
1692 static void am_run(struct am_state *state, int resume)
1693 {
1694         struct strbuf sb = STRBUF_INIT;
1695
1696         unlink(am_path(state, "dirtyindex"));
1697
1698         if (refresh_and_write_cache(REFRESH_QUIET, 0, 0) < 0)
1699                 die(_("unable to write index file"));
1700
1701         if (repo_index_has_changes(the_repository, NULL, &sb)) {
1702                 write_state_bool(state, "dirtyindex", 1);
1703                 die(_("Dirty index: cannot apply patches (dirty: %s)"), sb.buf);
1704         }
1705
1706         strbuf_release(&sb);
1707
1708         while (state->cur <= state->last) {
1709                 const char *mail = am_path(state, msgnum(state));
1710                 int apply_status;
1711
1712                 reset_ident_date();
1713
1714                 if (!file_exists(mail))
1715                         goto next;
1716
1717                 if (resume) {
1718                         validate_resume_state(state);
1719                 } else {
1720                         int skip;
1721
1722                         if (state->rebasing)
1723                                 skip = parse_mail_rebase(state, mail);
1724                         else
1725                                 skip = parse_mail(state, mail);
1726
1727                         if (skip)
1728                                 goto next; /* mail should be skipped */
1729
1730                         if (state->signoff)
1731                                 am_append_signoff(state);
1732
1733                         write_author_script(state);
1734                         write_commit_msg(state);
1735                 }
1736
1737                 if (state->interactive && do_interactive(state))
1738                         goto next;
1739
1740                 if (run_applypatch_msg_hook(state))
1741                         exit(1);
1742
1743                 say(state, stdout, _("Applying: %.*s"), linelen(state->msg), state->msg);
1744
1745                 apply_status = run_apply(state, NULL);
1746
1747                 if (apply_status && state->threeway) {
1748                         struct strbuf sb = STRBUF_INIT;
1749
1750                         strbuf_addstr(&sb, am_path(state, "patch-merge-index"));
1751                         apply_status = fall_back_threeway(state, sb.buf);
1752                         strbuf_release(&sb);
1753
1754                         /*
1755                          * Applying the patch to an earlier tree and merging
1756                          * the result may have produced the same tree as ours.
1757                          */
1758                         if (!apply_status &&
1759                             !repo_index_has_changes(the_repository, NULL, NULL)) {
1760                                 say(state, stdout, _("No changes -- Patch already applied."));
1761                                 goto next;
1762                         }
1763                 }
1764
1765                 if (apply_status) {
1766                         printf_ln(_("Patch failed at %s %.*s"), msgnum(state),
1767                                 linelen(state->msg), state->msg);
1768
1769                         if (advice_amworkdir)
1770                                 advise(_("Use 'git am --show-current-patch=diff' to see the failed patch"));
1771
1772                         die_user_resolve(state);
1773                 }
1774
1775                 do_commit(state);
1776
1777 next:
1778                 am_next(state);
1779
1780                 if (resume)
1781                         am_load(state);
1782                 resume = 0;
1783         }
1784
1785         if (!is_empty_or_missing_file(am_path(state, "rewritten"))) {
1786                 assert(state->rebasing);
1787                 copy_notes_for_rebase(state);
1788                 run_post_rewrite_hook(state);
1789         }
1790
1791         /*
1792          * In rebasing mode, it's up to the caller to take care of
1793          * housekeeping.
1794          */
1795         if (!state->rebasing) {
1796                 am_destroy(state);
1797                 close_object_store(the_repository->objects);
1798                 run_auto_gc(state->quiet);
1799         }
1800 }
1801
1802 /**
1803  * Resume the current am session after patch application failure. The user did
1804  * all the hard work, and we do not have to do any patch application. Just
1805  * trust and commit what the user has in the index and working tree.
1806  */
1807 static void am_resolve(struct am_state *state)
1808 {
1809         validate_resume_state(state);
1810
1811         say(state, stdout, _("Applying: %.*s"), linelen(state->msg), state->msg);
1812
1813         if (!repo_index_has_changes(the_repository, NULL, NULL)) {
1814                 printf_ln(_("No changes - did you forget to use 'git add'?\n"
1815                         "If there is nothing left to stage, chances are that something else\n"
1816                         "already introduced the same changes; you might want to skip this patch."));
1817                 die_user_resolve(state);
1818         }
1819
1820         if (unmerged_cache()) {
1821                 printf_ln(_("You still have unmerged paths in your index.\n"
1822                         "You should 'git add' each file with resolved conflicts to mark them as such.\n"
1823                         "You might run `git rm` on a file to accept \"deleted by them\" for it."));
1824                 die_user_resolve(state);
1825         }
1826
1827         if (state->interactive) {
1828                 write_index_patch(state);
1829                 if (do_interactive(state))
1830                         goto next;
1831         }
1832
1833         repo_rerere(the_repository, 0);
1834
1835         do_commit(state);
1836
1837 next:
1838         am_next(state);
1839         am_load(state);
1840         am_run(state, 0);
1841 }
1842
1843 /**
1844  * Performs a checkout fast-forward from `head` to `remote`. If `reset` is
1845  * true, any unmerged entries will be discarded. Returns 0 on success, -1 on
1846  * failure.
1847  */
1848 static int fast_forward_to(struct tree *head, struct tree *remote, int reset)
1849 {
1850         struct lock_file lock_file = LOCK_INIT;
1851         struct unpack_trees_options opts;
1852         struct tree_desc t[2];
1853
1854         if (parse_tree(head) || parse_tree(remote))
1855                 return -1;
1856
1857         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
1858
1859         refresh_cache(REFRESH_QUIET);
1860
1861         memset(&opts, 0, sizeof(opts));
1862         opts.head_idx = 1;
1863         opts.src_index = &the_index;
1864         opts.dst_index = &the_index;
1865         opts.update = 1;
1866         opts.merge = 1;
1867         opts.reset = reset;
1868         opts.fn = twoway_merge;
1869         init_tree_desc(&t[0], head->buffer, head->size);
1870         init_tree_desc(&t[1], remote->buffer, remote->size);
1871
1872         if (unpack_trees(2, t, &opts)) {
1873                 rollback_lock_file(&lock_file);
1874                 return -1;
1875         }
1876
1877         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
1878                 die(_("unable to write new index file"));
1879
1880         return 0;
1881 }
1882
1883 /**
1884  * Merges a tree into the index. The index's stat info will take precedence
1885  * over the merged tree's. Returns 0 on success, -1 on failure.
1886  */
1887 static int merge_tree(struct tree *tree)
1888 {
1889         struct lock_file lock_file = LOCK_INIT;
1890         struct unpack_trees_options opts;
1891         struct tree_desc t[1];
1892
1893         if (parse_tree(tree))
1894                 return -1;
1895
1896         hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);
1897
1898         memset(&opts, 0, sizeof(opts));
1899         opts.head_idx = 1;
1900         opts.src_index = &the_index;
1901         opts.dst_index = &the_index;
1902         opts.merge = 1;
1903         opts.fn = oneway_merge;
1904         init_tree_desc(&t[0], tree->buffer, tree->size);
1905
1906         if (unpack_trees(1, t, &opts)) {
1907                 rollback_lock_file(&lock_file);
1908                 return -1;
1909         }
1910
1911         if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
1912                 die(_("unable to write new index file"));
1913
1914         return 0;
1915 }
1916
1917 /**
1918  * Clean the index without touching entries that are not modified between
1919  * `head` and `remote`.
1920  */
1921 static int clean_index(const struct object_id *head, const struct object_id *remote)
1922 {
1923         struct tree *head_tree, *remote_tree, *index_tree;
1924         struct object_id index;
1925
1926         head_tree = parse_tree_indirect(head);
1927         if (!head_tree)
1928                 return error(_("Could not parse object '%s'."), oid_to_hex(head));
1929
1930         remote_tree = parse_tree_indirect(remote);
1931         if (!remote_tree)
1932                 return error(_("Could not parse object '%s'."), oid_to_hex(remote));
1933
1934         read_cache_unmerged();
1935
1936         if (fast_forward_to(head_tree, head_tree, 1))
1937                 return -1;
1938
1939         if (write_cache_as_tree(&index, 0, NULL))
1940                 return -1;
1941
1942         index_tree = parse_tree_indirect(&index);
1943         if (!index_tree)
1944                 return error(_("Could not parse object '%s'."), oid_to_hex(&index));
1945
1946         if (fast_forward_to(index_tree, remote_tree, 0))
1947                 return -1;
1948
1949         if (merge_tree(remote_tree))
1950                 return -1;
1951
1952         remove_branch_state(the_repository, 0);
1953
1954         return 0;
1955 }
1956
1957 /**
1958  * Resets rerere's merge resolution metadata.
1959  */
1960 static void am_rerere_clear(void)
1961 {
1962         struct string_list merge_rr = STRING_LIST_INIT_DUP;
1963         rerere_clear(the_repository, &merge_rr);
1964         string_list_clear(&merge_rr, 1);
1965 }
1966
1967 /**
1968  * Resume the current am session by skipping the current patch.
1969  */
1970 static void am_skip(struct am_state *state)
1971 {
1972         struct object_id head;
1973
1974         am_rerere_clear();
1975
1976         if (get_oid("HEAD", &head))
1977                 oidcpy(&head, the_hash_algo->empty_tree);
1978
1979         if (clean_index(&head, &head))
1980                 die(_("failed to clean index"));
1981
1982         if (state->rebasing) {
1983                 FILE *fp = xfopen(am_path(state, "rewritten"), "a");
1984
1985                 assert(!is_null_oid(&state->orig_commit));
1986                 fprintf(fp, "%s ", oid_to_hex(&state->orig_commit));
1987                 fprintf(fp, "%s\n", oid_to_hex(&head));
1988                 fclose(fp);
1989         }
1990
1991         am_next(state);
1992         am_load(state);
1993         am_run(state, 0);
1994 }
1995
1996 /**
1997  * Returns true if it is safe to reset HEAD to the ORIG_HEAD, false otherwise.
1998  *
1999  * It is not safe to reset HEAD when:
2000  * 1. git-am previously failed because the index was dirty.
2001  * 2. HEAD has moved since git-am previously failed.
2002  */
2003 static int safe_to_abort(const struct am_state *state)
2004 {
2005         struct strbuf sb = STRBUF_INIT;
2006         struct object_id abort_safety, head;
2007
2008         if (file_exists(am_path(state, "dirtyindex")))
2009                 return 0;
2010
2011         if (read_state_file(&sb, state, "abort-safety", 1) > 0) {
2012                 if (get_oid_hex(sb.buf, &abort_safety))
2013                         die(_("could not parse %s"), am_path(state, "abort-safety"));
2014         } else
2015                 oidclr(&abort_safety);
2016         strbuf_release(&sb);
2017
2018         if (get_oid("HEAD", &head))
2019                 oidclr(&head);
2020
2021         if (oideq(&head, &abort_safety))
2022                 return 1;
2023
2024         warning(_("You seem to have moved HEAD since the last 'am' failure.\n"
2025                 "Not rewinding to ORIG_HEAD"));
2026
2027         return 0;
2028 }
2029
2030 /**
2031  * Aborts the current am session if it is safe to do so.
2032  */
2033 static void am_abort(struct am_state *state)
2034 {
2035         struct object_id curr_head, orig_head;
2036         int has_curr_head, has_orig_head;
2037         char *curr_branch;
2038
2039         if (!safe_to_abort(state)) {
2040                 am_destroy(state);
2041                 return;
2042         }
2043
2044         am_rerere_clear();
2045
2046         curr_branch = resolve_refdup("HEAD", 0, &curr_head, NULL);
2047         has_curr_head = curr_branch && !is_null_oid(&curr_head);
2048         if (!has_curr_head)
2049                 oidcpy(&curr_head, the_hash_algo->empty_tree);
2050
2051         has_orig_head = !get_oid("ORIG_HEAD", &orig_head);
2052         if (!has_orig_head)
2053                 oidcpy(&orig_head, the_hash_algo->empty_tree);
2054
2055         clean_index(&curr_head, &orig_head);
2056
2057         if (has_orig_head)
2058                 update_ref("am --abort", "HEAD", &orig_head,
2059                            has_curr_head ? &curr_head : NULL, 0,
2060                            UPDATE_REFS_DIE_ON_ERR);
2061         else if (curr_branch)
2062                 delete_ref(NULL, curr_branch, NULL, REF_NO_DEREF);
2063
2064         free(curr_branch);
2065         am_destroy(state);
2066 }
2067
2068 static int show_patch(struct am_state *state, enum show_patch_type sub_mode)
2069 {
2070         struct strbuf sb = STRBUF_INIT;
2071         const char *patch_path;
2072         int len;
2073
2074         if (!is_null_oid(&state->orig_commit)) {
2075                 const char *av[4] = { "show", NULL, "--", NULL };
2076                 char *new_oid_str;
2077                 int ret;
2078
2079                 av[1] = new_oid_str = xstrdup(oid_to_hex(&state->orig_commit));
2080                 ret = run_command_v_opt(av, RUN_GIT_CMD);
2081                 free(new_oid_str);
2082                 return ret;
2083         }
2084
2085         switch (sub_mode) {
2086         case SHOW_PATCH_RAW:
2087                 patch_path = am_path(state, msgnum(state));
2088                 break;
2089         case SHOW_PATCH_DIFF:
2090                 patch_path = am_path(state, "patch");
2091                 break;
2092         default:
2093                 BUG("invalid mode for --show-current-patch");
2094         }
2095
2096         len = strbuf_read_file(&sb, patch_path, 0);
2097         if (len < 0)
2098                 die_errno(_("failed to read '%s'"), patch_path);
2099
2100         setup_pager();
2101         write_in_full(1, sb.buf, sb.len);
2102         strbuf_release(&sb);
2103         return 0;
2104 }
2105
2106 /**
2107  * parse_options() callback that validates and sets opt->value to the
2108  * PATCH_FORMAT_* enum value corresponding to `arg`.
2109  */
2110 static int parse_opt_patchformat(const struct option *opt, const char *arg, int unset)
2111 {
2112         int *opt_value = opt->value;
2113
2114         if (unset)
2115                 *opt_value = PATCH_FORMAT_UNKNOWN;
2116         else if (!strcmp(arg, "mbox"))
2117                 *opt_value = PATCH_FORMAT_MBOX;
2118         else if (!strcmp(arg, "stgit"))
2119                 *opt_value = PATCH_FORMAT_STGIT;
2120         else if (!strcmp(arg, "stgit-series"))
2121                 *opt_value = PATCH_FORMAT_STGIT_SERIES;
2122         else if (!strcmp(arg, "hg"))
2123                 *opt_value = PATCH_FORMAT_HG;
2124         else if (!strcmp(arg, "mboxrd"))
2125                 *opt_value = PATCH_FORMAT_MBOXRD;
2126         /*
2127          * Please update $__git_patchformat in git-completion.bash
2128          * when you add new options
2129          */
2130         else
2131                 return error(_("Invalid value for --patch-format: %s"), arg);
2132         return 0;
2133 }
2134
2135 enum resume_type {
2136         RESUME_FALSE = 0,
2137         RESUME_APPLY,
2138         RESUME_RESOLVED,
2139         RESUME_SKIP,
2140         RESUME_ABORT,
2141         RESUME_QUIT,
2142         RESUME_SHOW_PATCH
2143 };
2144
2145 struct resume_mode {
2146         enum resume_type mode;
2147         enum show_patch_type sub_mode;
2148 };
2149
2150 static int parse_opt_show_current_patch(const struct option *opt, const char *arg, int unset)
2151 {
2152         int *opt_value = opt->value;
2153         struct resume_mode *resume = container_of(opt_value, struct resume_mode, mode);
2154
2155         /*
2156          * Please update $__git_showcurrentpatch in git-completion.bash
2157          * when you add new options
2158          */
2159         const char *valid_modes[] = {
2160                 [SHOW_PATCH_DIFF] = "diff",
2161                 [SHOW_PATCH_RAW] = "raw"
2162         };
2163         int new_value = SHOW_PATCH_RAW;
2164
2165         if (arg) {
2166                 for (new_value = 0; new_value < ARRAY_SIZE(valid_modes); new_value++) {
2167                         if (!strcmp(arg, valid_modes[new_value]))
2168                                 break;
2169                 }
2170                 if (new_value >= ARRAY_SIZE(valid_modes))
2171                         return error(_("Invalid value for --show-current-patch: %s"), arg);
2172         }
2173
2174         if (resume->mode == RESUME_SHOW_PATCH && new_value != resume->sub_mode)
2175                 return error(_("--show-current-patch=%s is incompatible with "
2176                                "--show-current-patch=%s"),
2177                              arg, valid_modes[resume->sub_mode]);
2178
2179         resume->mode = RESUME_SHOW_PATCH;
2180         resume->sub_mode = new_value;
2181         return 0;
2182 }
2183
2184 static int git_am_config(const char *k, const char *v, void *cb)
2185 {
2186         int status;
2187
2188         status = git_gpg_config(k, v, NULL);
2189         if (status)
2190                 return status;
2191
2192         return git_default_config(k, v, NULL);
2193 }
2194
2195 int cmd_am(int argc, const char **argv, const char *prefix)
2196 {
2197         struct am_state state;
2198         int binary = -1;
2199         int keep_cr = -1;
2200         int patch_format = PATCH_FORMAT_UNKNOWN;
2201         struct resume_mode resume = { .mode = RESUME_FALSE };
2202         int in_progress;
2203         int ret = 0;
2204
2205         const char * const usage[] = {
2206                 N_("git am [<options>] [(<mbox> | <Maildir>)...]"),
2207                 N_("git am [<options>] (--continue | --skip | --abort)"),
2208                 NULL
2209         };
2210
2211         struct option options[] = {
2212                 OPT_BOOL('i', "interactive", &state.interactive,
2213                         N_("run interactively")),
2214                 OPT_HIDDEN_BOOL('b', "binary", &binary,
2215                         N_("historical option -- no-op")),
2216                 OPT_BOOL('3', "3way", &state.threeway,
2217                         N_("allow fall back on 3way merging if needed")),
2218                 OPT__QUIET(&state.quiet, N_("be quiet")),
2219                 OPT_SET_INT('s', "signoff", &state.signoff,
2220                         N_("add a Signed-off-by line to the commit message"),
2221                         SIGNOFF_EXPLICIT),
2222                 OPT_BOOL('u', "utf8", &state.utf8,
2223                         N_("recode into utf8 (default)")),
2224                 OPT_SET_INT('k', "keep", &state.keep,
2225                         N_("pass -k flag to git-mailinfo"), KEEP_TRUE),
2226                 OPT_SET_INT(0, "keep-non-patch", &state.keep,
2227                         N_("pass -b flag to git-mailinfo"), KEEP_NON_PATCH),
2228                 OPT_BOOL('m', "message-id", &state.message_id,
2229                         N_("pass -m flag to git-mailinfo")),
2230                 OPT_SET_INT_F(0, "keep-cr", &keep_cr,
2231                         N_("pass --keep-cr flag to git-mailsplit for mbox format"),
2232                         1, PARSE_OPT_NONEG),
2233                 OPT_SET_INT_F(0, "no-keep-cr", &keep_cr,
2234                         N_("do not pass --keep-cr flag to git-mailsplit independent of am.keepcr"),
2235                         0, PARSE_OPT_NONEG),
2236                 OPT_BOOL('c', "scissors", &state.scissors,
2237                         N_("strip everything before a scissors line")),
2238                 OPT_PASSTHRU_ARGV(0, "whitespace", &state.git_apply_opts, N_("action"),
2239                         N_("pass it through git-apply"),
2240                         0),
2241                 OPT_PASSTHRU_ARGV(0, "ignore-space-change", &state.git_apply_opts, NULL,
2242                         N_("pass it through git-apply"),
2243                         PARSE_OPT_NOARG),
2244                 OPT_PASSTHRU_ARGV(0, "ignore-whitespace", &state.git_apply_opts, NULL,
2245                         N_("pass it through git-apply"),
2246                         PARSE_OPT_NOARG),
2247                 OPT_PASSTHRU_ARGV(0, "directory", &state.git_apply_opts, N_("root"),
2248                         N_("pass it through git-apply"),
2249                         0),
2250                 OPT_PASSTHRU_ARGV(0, "exclude", &state.git_apply_opts, N_("path"),
2251                         N_("pass it through git-apply"),
2252                         0),
2253                 OPT_PASSTHRU_ARGV(0, "include", &state.git_apply_opts, N_("path"),
2254                         N_("pass it through git-apply"),
2255                         0),
2256                 OPT_PASSTHRU_ARGV('C', NULL, &state.git_apply_opts, N_("n"),
2257                         N_("pass it through git-apply"),
2258                         0),
2259                 OPT_PASSTHRU_ARGV('p', NULL, &state.git_apply_opts, N_("num"),
2260                         N_("pass it through git-apply"),
2261                         0),
2262                 OPT_CALLBACK(0, "patch-format", &patch_format, N_("format"),
2263                         N_("format the patch(es) are in"),
2264                         parse_opt_patchformat),
2265                 OPT_PASSTHRU_ARGV(0, "reject", &state.git_apply_opts, NULL,
2266                         N_("pass it through git-apply"),
2267                         PARSE_OPT_NOARG),
2268                 OPT_STRING(0, "resolvemsg", &state.resolvemsg, NULL,
2269                         N_("override error message when patch failure occurs")),
2270                 OPT_CMDMODE(0, "continue", &resume.mode,
2271                         N_("continue applying patches after resolving a conflict"),
2272                         RESUME_RESOLVED),
2273                 OPT_CMDMODE('r', "resolved", &resume.mode,
2274                         N_("synonyms for --continue"),
2275                         RESUME_RESOLVED),
2276                 OPT_CMDMODE(0, "skip", &resume.mode,
2277                         N_("skip the current patch"),
2278                         RESUME_SKIP),
2279                 OPT_CMDMODE(0, "abort", &resume.mode,
2280                         N_("restore the original branch and abort the patching operation."),
2281                         RESUME_ABORT),
2282                 OPT_CMDMODE(0, "quit", &resume.mode,
2283                         N_("abort the patching operation but keep HEAD where it is."),
2284                         RESUME_QUIT),
2285                 { OPTION_CALLBACK, 0, "show-current-patch", &resume.mode,
2286                   "(diff|raw)",
2287                   N_("show the patch being applied"),
2288                   PARSE_OPT_CMDMODE | PARSE_OPT_OPTARG | PARSE_OPT_NONEG | PARSE_OPT_LITERAL_ARGHELP,
2289                   parse_opt_show_current_patch, RESUME_SHOW_PATCH },
2290                 OPT_BOOL(0, "committer-date-is-author-date",
2291                         &state.committer_date_is_author_date,
2292                         N_("lie about committer date")),
2293                 OPT_BOOL(0, "ignore-date", &state.ignore_date,
2294                         N_("use current timestamp for author date")),
2295                 OPT_RERERE_AUTOUPDATE(&state.allow_rerere_autoupdate),
2296                 { OPTION_STRING, 'S', "gpg-sign", &state.sign_commit, N_("key-id"),
2297                   N_("GPG-sign commits"),
2298                   PARSE_OPT_OPTARG, NULL, (intptr_t) "" },
2299                 OPT_HIDDEN_BOOL(0, "rebasing", &state.rebasing,
2300                         N_("(internal use for git-rebase)")),
2301                 OPT_END()
2302         };
2303
2304         if (argc == 2 && !strcmp(argv[1], "-h"))
2305                 usage_with_options(usage, options);
2306
2307         git_config(git_am_config, NULL);
2308
2309         am_state_init(&state);
2310
2311         in_progress = am_in_progress(&state);
2312         if (in_progress)
2313                 am_load(&state);
2314
2315         argc = parse_options(argc, argv, prefix, options, usage, 0);
2316
2317         if (binary >= 0)
2318                 fprintf_ln(stderr, _("The -b/--binary option has been a no-op for long time, and\n"
2319                                 "it will be removed. Please do not use it anymore."));
2320
2321         /* Ensure a valid committer ident can be constructed */
2322         git_committer_info(IDENT_STRICT);
2323
2324         if (repo_read_index_preload(the_repository, NULL, 0) < 0)
2325                 die(_("failed to read the index"));
2326
2327         if (in_progress) {
2328                 /*
2329                  * Catch user error to feed us patches when there is a session
2330                  * in progress:
2331                  *
2332                  * 1. mbox path(s) are provided on the command-line.
2333                  * 2. stdin is not a tty: the user is trying to feed us a patch
2334                  *    from standard input. This is somewhat unreliable -- stdin
2335                  *    could be /dev/null for example and the caller did not
2336                  *    intend to feed us a patch but wanted to continue
2337                  *    unattended.
2338                  */
2339                 if (argc || (resume.mode == RESUME_FALSE && !isatty(0)))
2340                         die(_("previous rebase directory %s still exists but mbox given."),
2341                                 state.dir);
2342
2343                 if (resume.mode == RESUME_FALSE)
2344                         resume.mode = RESUME_APPLY;
2345
2346                 if (state.signoff == SIGNOFF_EXPLICIT)
2347                         am_append_signoff(&state);
2348         } else {
2349                 struct argv_array paths = ARGV_ARRAY_INIT;
2350                 int i;
2351
2352                 /*
2353                  * Handle stray state directory in the independent-run case. In
2354                  * the --rebasing case, it is up to the caller to take care of
2355                  * stray directories.
2356                  */
2357                 if (file_exists(state.dir) && !state.rebasing) {
2358                         if (resume.mode == RESUME_ABORT || resume.mode == RESUME_QUIT) {
2359                                 am_destroy(&state);
2360                                 am_state_release(&state);
2361                                 return 0;
2362                         }
2363
2364                         die(_("Stray %s directory found.\n"
2365                                 "Use \"git am --abort\" to remove it."),
2366                                 state.dir);
2367                 }
2368
2369                 if (resume.mode)
2370                         die(_("Resolve operation not in progress, we are not resuming."));
2371
2372                 for (i = 0; i < argc; i++) {
2373                         if (is_absolute_path(argv[i]) || !prefix)
2374                                 argv_array_push(&paths, argv[i]);
2375                         else
2376                                 argv_array_push(&paths, mkpath("%s/%s", prefix, argv[i]));
2377                 }
2378
2379                 if (state.interactive && !paths.argc)
2380                         die(_("interactive mode requires patches on the command line"));
2381
2382                 am_setup(&state, patch_format, paths.argv, keep_cr);
2383
2384                 argv_array_clear(&paths);
2385         }
2386
2387         switch (resume.mode) {
2388         case RESUME_FALSE:
2389                 am_run(&state, 0);
2390                 break;
2391         case RESUME_APPLY:
2392                 am_run(&state, 1);
2393                 break;
2394         case RESUME_RESOLVED:
2395                 am_resolve(&state);
2396                 break;
2397         case RESUME_SKIP:
2398                 am_skip(&state);
2399                 break;
2400         case RESUME_ABORT:
2401                 am_abort(&state);
2402                 break;
2403         case RESUME_QUIT:
2404                 am_rerere_clear();
2405                 am_destroy(&state);
2406                 break;
2407         case RESUME_SHOW_PATCH:
2408                 ret = show_patch(&state, resume.sub_mode);
2409                 break;
2410         default:
2411                 BUG("invalid resume value");
2412         }
2413
2414         am_state_release(&state);
2415
2416         return ret;
2417 }