help.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "builtin.h"
   4 #include "exec-cmd.h"
   5 #include "run-command.h"
   6 #include "levenshtein.h"
   7 #include "help.h"
   8 #include "command-list.h"
   9 #include "string-list.h"
  10 #include "column.h"
  11 #include "version.h"
  12 #include "refs.h"
  13 #include "parse-options.h"
  14
  15 struct category_description {
  16         uint32_t category;
  17         const char *desc;
  18 };
  19 static uint32_t common_mask =
  20         CAT_init | CAT_worktree | CAT_info |
  21         CAT_history | CAT_remote;
  22 static struct category_description common_categories[] = {
  23         { CAT_init, N_("start a working area (see also: git help tutorial)") },
  24         { CAT_worktree, N_("work on the current change (see also: git help everyday)") },
  25         { CAT_info, N_("examine the history and state (see also: git help revisions)") },
  26         { CAT_history, N_("grow, mark and tweak your common history") },
  27         { CAT_remote, N_("collaborate (see also: git help workflows)") },
  28         { 0, NULL }
  29 };
  30 static struct category_description main_categories[] = {
  31         { CAT_mainporcelain, N_("Main Porcelain Commands") },
  32         { CAT_ancillarymanipulators, N_("Ancillary Commands / Manipulators") },
  33         { CAT_ancillaryinterrogators, N_("Ancillary Commands / Interrogators") },
  34         { CAT_foreignscminterface, N_("Interacting with Others") },
  35         { CAT_plumbingmanipulators, N_("Low-level Commands / Manipulators") },
  36         { CAT_plumbinginterrogators, N_("Low-level Commands / Interrogators") },
  37         { CAT_synchingrepositories, N_("Low-level Commands / Synching Repositories") },
  38         { CAT_purehelpers, N_("Low-level Commands / Internal Helpers") },
  39         { 0, NULL }
  40 };
  41
  42 static const char *drop_prefix(const char *name, uint32_t category)
  43 {
  44         const char *new_name;
  45
  46         if (skip_prefix(name, "git-", &new_name))
  47                 return new_name;
  48         if (category == CAT_guide && skip_prefix(name, "git", &new_name))
  49                 return new_name;
  50         return name;
  51
  52 }
  53
  54 static void extract_cmds(struct cmdname_help **p_cmds, uint32_t mask)
  55 {
  56         int i, nr = 0;
  57         struct cmdname_help *cmds;
  58
  59         if (ARRAY_SIZE(command_list) == 0)
  60                 BUG("empty command_list[] is a sign of broken generate-cmdlist.sh");
  61
  62         ALLOC_ARRAY(cmds, ARRAY_SIZE(command_list) + 1);
  63
  64         for (i = 0; i < ARRAY_SIZE(command_list); i++) {
  65                 const struct cmdname_help *cmd = command_list + i;
  66
  67                 if (!(cmd->category & mask))
  68                         continue;
  69
  70                 cmds[nr] = *cmd;
  71                 cmds[nr].name = drop_prefix(cmd->name, cmd->category);
  72
  73                 nr++;
  74         }
  75         cmds[nr].name = NULL;
  76         *p_cmds = cmds;
  77 }
  78
  79 static void print_command_list(const struct cmdname_help *cmds,
  80                                uint32_t mask, int longest)
  81 {
  82         int i;
  83
  84         for (i = 0; cmds[i].name; i++) {
  85                 if (cmds[i].category & mask) {
  86                         printf("   %s   ", cmds[i].name);
  87                         mput_char(' ', longest - strlen(cmds[i].name));
  88                         puts(_(cmds[i].help));
  89                 }
  90         }
  91 }
  92
  93 static int cmd_name_cmp(const void *elem1, const void *elem2)
  94 {
  95         const struct cmdname_help *e1 = elem1;
  96         const struct cmdname_help *e2 = elem2;
  97
  98         return strcmp(e1->name, e2->name);
  99 }
 100
 101 static void print_cmd_by_category(const struct category_description *catdesc,
 102                                   int *longest_p)
 103 {
 104         struct cmdname_help *cmds;
 105         int longest = 0;
 106         int i, nr = 0;
 107         uint32_t mask = 0;
 108
 109         for (i = 0; catdesc[i].desc; i++)
 110                 mask |= catdesc[i].category;
 111
 112         extract_cmds(&cmds, mask);
 113
 114         for (i = 0; cmds[i].name; i++, nr++) {
 115                 if (longest < strlen(cmds[i].name))
 116                         longest = strlen(cmds[i].name);
 117         }
 118         QSORT(cmds, nr, cmd_name_cmp);
 119
 120         for (i = 0; catdesc[i].desc; i++) {
 121                 uint32_t mask = catdesc[i].category;
 122                 const char *desc = catdesc[i].desc;
 123
 124                 printf("\n%s\n", _(desc));
 125                 print_command_list(cmds, mask, longest);
 126         }
 127         free(cmds);
 128         if (longest_p)
 129                 *longest_p = longest;
 130 }
 131
 132 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
 133 {
 134         struct cmdname *ent;
 135         FLEX_ALLOC_MEM(ent, name, name, len);
 136         ent->len = len;
 137
 138         ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
 139         cmds->names[cmds->cnt++] = ent;
 140 }
 141
 142 static void clean_cmdnames(struct cmdnames *cmds)
 143 {
 144         int i;
 145         for (i = 0; i < cmds->cnt; ++i)
 146                 free(cmds->names[i]);
 147         free(cmds->names);
 148         cmds->cnt = 0;
 149         cmds->alloc = 0;
 150 }
 151
 152 static int cmdname_compare(const void *a_, const void *b_)
 153 {
 154         struct cmdname *a = *(struct cmdname **)a_;
 155         struct cmdname *b = *(struct cmdname **)b_;
 156         return strcmp(a->name, b->name);
 157 }
 158
 159 static void uniq(struct cmdnames *cmds)
 160 {
 161         int i, j;
 162
 163         if (!cmds->cnt)
 164                 return;
 165
 166         for (i = j = 1; i < cmds->cnt; i++) {
 167                 if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
 168                         free(cmds->names[i]);
 169                 else
 170                         cmds->names[j++] = cmds->names[i];
 171         }
 172
 173         cmds->cnt = j;
 174 }
 175
 176 void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
 177 {
 178         int ci, cj, ei;
 179         int cmp;
 180
 181         ci = cj = ei = 0;
 182         while (ci < cmds->cnt && ei < excludes->cnt) {
 183                 cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
 184                 if (cmp < 0)
 185                         cmds->names[cj++] = cmds->names[ci++];
 186                 else if (cmp == 0) {
 187                         ei++;
 188                         free(cmds->names[ci++]);
 189                 } else if (cmp > 0)
 190                         ei++;
 191         }
 192
 193         while (ci < cmds->cnt)
 194                 cmds->names[cj++] = cmds->names[ci++];
 195
 196         cmds->cnt = cj;
 197 }
 198
 199 static void pretty_print_cmdnames(struct cmdnames *cmds, unsigned int colopts)
 200 {
 201         struct string_list list = STRING_LIST_INIT_NODUP;
 202         struct column_options copts;
 203         int i;
 204
 205         for (i = 0; i < cmds->cnt; i++)
 206                 string_list_append(&list, cmds->names[i]->name);
 207         /*
 208          * always enable column display, we only consult column.*
 209          * about layout strategy and stuff
 210          */
 211         colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
 212         memset(&copts, 0, sizeof(copts));
 213         copts.indent = "  ";
 214         copts.padding = 2;
 215         print_columns(&list, colopts, &copts);
 216         string_list_clear(&list, 0);
 217 }
 218
 219 static void list_commands_in_dir(struct cmdnames *cmds,
 220                                          const char *path,
 221                                          const char *prefix)
 222 {
 223         DIR *dir = opendir(path);
 224         struct dirent *de;
 225         struct strbuf buf = STRBUF_INIT;
 226         int len;
 227
 228         if (!dir)
 229                 return;
 230         if (!prefix)
 231                 prefix = "git-";
 232
 233         strbuf_addf(&buf, "%s/", path);
 234         len = buf.len;
 235
 236         while ((de = readdir(dir)) != NULL) {
 237                 const char *ent;
 238                 size_t entlen;
 239
 240                 if (!skip_prefix(de->d_name, prefix, &ent))
 241                         continue;
 242
 243                 strbuf_setlen(&buf, len);
 244                 strbuf_addstr(&buf, de->d_name);
 245                 if (!is_executable(buf.buf))
 246                         continue;
 247
 248                 entlen = strlen(ent);
 249                 strip_suffix(ent, ".exe", &entlen);
 250
 251                 add_cmdname(cmds, ent, entlen);
 252         }
 253         closedir(dir);
 254         strbuf_release(&buf);
 255 }
 256
 257 void load_command_list(const char *prefix,
 258                 struct cmdnames *main_cmds,
 259                 struct cmdnames *other_cmds)
 260 {
 261         const char *env_path = getenv("PATH");
 262         const char *exec_path = git_exec_path();
 263
 264         if (exec_path) {
 265                 list_commands_in_dir(main_cmds, exec_path, prefix);
 266                 QSORT(main_cmds->names, main_cmds->cnt, cmdname_compare);
 267                 uniq(main_cmds);
 268         }
 269
 270         if (env_path) {
 271                 char *paths, *path, *colon;
 272                 path = paths = xstrdup(env_path);
 273                 while (1) {
 274                         if ((colon = strchr(path, PATH_SEP)))
 275                                 *colon = 0;
 276                         if (!exec_path || strcmp(path, exec_path))
 277                                 list_commands_in_dir(other_cmds, path, prefix);
 278
 279                         if (!colon)
 280                                 break;
 281                         path = colon + 1;
 282                 }
 283                 free(paths);
 284
 285                 QSORT(other_cmds->names, other_cmds->cnt, cmdname_compare);
 286                 uniq(other_cmds);
 287         }
 288         exclude_cmds(other_cmds, main_cmds);
 289 }
 290
 291 void list_commands(unsigned int colopts,
 292                    struct cmdnames *main_cmds, struct cmdnames *other_cmds)
 293 {
 294         if (main_cmds->cnt) {
 295                 const char *exec_path = git_exec_path();
 296                 printf_ln(_("available git commands in '%s'"), exec_path);
 297                 putchar('\n');
 298                 pretty_print_cmdnames(main_cmds, colopts);
 299                 putchar('\n');
 300         }
 301
 302         if (other_cmds->cnt) {
 303                 printf_ln(_("git commands available from elsewhere on your $PATH"));
 304                 putchar('\n');
 305                 pretty_print_cmdnames(other_cmds, colopts);
 306                 putchar('\n');
 307         }
 308 }
 309
 310 void list_common_cmds_help(void)
 311 {
 312         puts(_("These are common Git commands used in various situations:"));
 313         print_cmd_by_category(common_categories, NULL);
 314 }
 315
 316 void list_all_main_cmds(struct string_list *list)
 317 {
 318         struct cmdnames main_cmds, other_cmds;
 319         int i;
 320
 321         memset(&main_cmds, 0, sizeof(main_cmds));
 322         memset(&other_cmds, 0, sizeof(other_cmds));
 323         load_command_list("git-", &main_cmds, &other_cmds);
 324
 325         for (i = 0; i < main_cmds.cnt; i++)
 326                 string_list_append(list, main_cmds.names[i]->name);
 327
 328         clean_cmdnames(&main_cmds);
 329         clean_cmdnames(&other_cmds);
 330 }
 331
 332 void list_all_other_cmds(struct string_list *list)
 333 {
 334         struct cmdnames main_cmds, other_cmds;
 335         int i;
 336
 337         memset(&main_cmds, 0, sizeof(main_cmds));
 338         memset(&other_cmds, 0, sizeof(other_cmds));
 339         load_command_list("git-", &main_cmds, &other_cmds);
 340
 341         for (i = 0; i < other_cmds.cnt; i++)
 342                 string_list_append(list, other_cmds.names[i]->name);
 343
 344         clean_cmdnames(&main_cmds);
 345         clean_cmdnames(&other_cmds);
 346 }
 347
 348 void list_cmds_by_category(struct string_list *list,
 349                            const char *cat)
 350 {
 351         int i, n = ARRAY_SIZE(command_list);
 352         uint32_t cat_id = 0;
 353
 354         for (i = 0; category_names[i]; i++) {
 355                 if (!strcmp(cat, category_names[i])) {
 356                         cat_id = 1UL << i;
 357                         break;
 358                 }
 359         }
 360         if (!cat_id)
 361                 die(_("unsupported command listing type '%s'"), cat);
 362
 363         for (i = 0; i < n; i++) {
 364                 struct cmdname_help *cmd = command_list + i;
 365
 366                 if (!(cmd->category & cat_id))
 367                         continue;
 368                 string_list_append(list, drop_prefix(cmd->name, cmd->category));
 369         }
 370 }
 371
 372 void list_cmds_by_config(struct string_list *list)
 373 {
 374         const char *cmd_list;
 375
 376         /*
 377          * There's no actual repository setup at this point (and even
 378          * if there is, we don't really care; only global config
 379          * matters). If we accidentally set up a repository, it's ok
 380          * too since the caller (git --list-cmds=) should exit shortly
 381          * anyway.
 382          */
 383         if (git_config_get_string_const("completion.commands", &cmd_list))
 384                 return;
 385
 386         string_list_sort(list);
 387         string_list_remove_duplicates(list, 0);
 388
 389         while (*cmd_list) {
 390                 struct strbuf sb = STRBUF_INIT;
 391                 const char *p = strchrnul(cmd_list, ' ');
 392
 393                 strbuf_add(&sb, cmd_list, p - cmd_list);
 394                 if (*cmd_list == '-')
 395                         string_list_remove(list, cmd_list + 1, 0);
 396                 else
 397                         string_list_insert(list, sb.buf);
 398                 strbuf_release(&sb);
 399                 while (*p == ' ')
 400                         p++;
 401                 cmd_list = p;
 402         }
 403 }
 404
 405 void list_common_guides_help(void)
 406 {
 407         struct category_description catdesc[] = {
 408                 { CAT_guide, N_("The common Git guides are:") },
 409                 { 0, NULL }
 410         };
 411         print_cmd_by_category(catdesc, NULL);
 412         putchar('\n');
 413 }
 414
 415 struct slot_expansion {
 416         const char *prefix;
 417         const char *placeholder;
 418         void (*fn)(struct string_list *list, const char *prefix);
 419         int found;
 420 };
 421
 422 void list_config_help(int for_human)
 423 {
 424         struct slot_expansion slot_expansions[] = {
 425                 { "advice", "*", list_config_advices },
 426                 { "color.branch", "<slot>", list_config_color_branch_slots },
 427                 { "color.decorate", "<slot>", list_config_color_decorate_slots },
 428                 { "color.diff", "<slot>", list_config_color_diff_slots },
 429                 { "color.grep", "<slot>", list_config_color_grep_slots },
 430                 { "color.interactive", "<slot>", list_config_color_interactive_slots },
 431                 { "color.remote", "<slot>", list_config_color_sideband_slots },
 432                 { "color.status", "<slot>", list_config_color_status_slots },
 433                 { "fsck", "<msg-id>", list_config_fsck_msg_ids },
 434                 { "receive.fsck", "<msg-id>", list_config_fsck_msg_ids },
 435                 { NULL, NULL, NULL }
 436         };
 437         const char **p;
 438         struct slot_expansion *e;
 439         struct string_list keys = STRING_LIST_INIT_DUP;
 440         int i;
 441
 442         for (p = config_name_list; *p; p++) {
 443                 const char *var = *p;
 444                 struct strbuf sb = STRBUF_INIT;
 445
 446                 for (e = slot_expansions; e->prefix; e++) {
 447
 448                         strbuf_reset(&sb);
 449                         strbuf_addf(&sb, "%s.%s", e->prefix, e->placeholder);
 450                         if (!strcasecmp(var, sb.buf)) {
 451                                 e->fn(&keys, e->prefix);
 452                                 e->found++;
 453                                 break;
 454                         }
 455                 }
 456                 strbuf_release(&sb);
 457                 if (!e->prefix)
 458                         string_list_append(&keys, var);
 459         }
 460
 461         for (e = slot_expansions; e->prefix; e++)
 462                 if (!e->found)
 463                         BUG("slot_expansion %s.%s is not used",
 464                             e->prefix, e->placeholder);
 465
 466         string_list_sort(&keys);
 467         for (i = 0; i < keys.nr; i++) {
 468                 const char *var = keys.items[i].string;
 469                 const char *wildcard, *tag, *cut;
 470
 471                 if (for_human) {
 472                         puts(var);
 473                         continue;
 474                 }
 475
 476                 wildcard = strchr(var, '*');
 477                 tag = strchr(var, '<');
 478
 479                 if (!wildcard && !tag) {
 480                         puts(var);
 481                         continue;
 482                 }
 483
 484                 if (wildcard && !tag)
 485                         cut = wildcard;
 486                 else if (!wildcard && tag)
 487                         cut = tag;
 488                 else
 489                         cut = wildcard < tag ? wildcard : tag;
 490
 491                 /*
 492                  * We may produce duplicates, but that's up to
 493                  * git-completion.bash to handle
 494                  */
 495                 printf("%.*s\n", (int)(cut - var), var);
 496         }
 497         string_list_clear(&keys, 0);
 498 }
 499
 500 static int get_alias(const char *var, const char *value, void *data)
 501 {
 502         struct string_list *list = data;
 503
 504         if (skip_prefix(var, "alias.", &var))
 505                 string_list_append(list, var)->util = xstrdup(value);
 506
 507         return 0;
 508 }
 509
 510 void list_all_cmds_help(void)
 511 {
 512         struct string_list others = STRING_LIST_INIT_DUP;
 513         struct string_list alias_list = STRING_LIST_INIT_DUP;
 514         struct cmdname_help *aliases;
 515         int i, longest;
 516
 517         printf_ln(_("See 'git help <command>' to read about a specific subcommand"));
 518         print_cmd_by_category(main_categories, &longest);
 519
 520         list_all_other_cmds(&others);
 521         if (others.nr)
 522                 printf("\n%s\n", _("External commands"));
 523         for (i = 0; i < others.nr; i++)
 524                 printf("   %s\n", others.items[i].string);
 525         string_list_clear(&others, 0);
 526
 527         git_config(get_alias, &alias_list);
 528         string_list_sort(&alias_list);
 529         if (alias_list.nr) {
 530                 printf("\n%s\n", _("Command aliases"));
 531                 ALLOC_ARRAY(aliases, alias_list.nr + 1);
 532                 for (i = 0; i < alias_list.nr; i++) {
 533                         aliases[i].name = alias_list.items[i].string;
 534                         aliases[i].help = alias_list.items[i].util;
 535                         aliases[i].category = 1;
 536                 }
 537                 aliases[alias_list.nr].name = NULL;
 538                 print_command_list(aliases, 1, longest);
 539                 free(aliases);
 540         }
 541         string_list_clear(&alias_list, 1);
 542 }
 543
 544 int is_in_cmdlist(struct cmdnames *c, const char *s)
 545 {
 546         int i;
 547         for (i = 0; i < c->cnt; i++)
 548                 if (!strcmp(s, c->names[i]->name))
 549                         return 1;
 550         return 0;
 551 }
 552
 553 static int autocorrect;
 554 static struct cmdnames aliases;
 555
 556 static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
 557 {
 558         const char *p;
 559
 560         if (!strcmp(var, "help.autocorrect"))
 561                 autocorrect = git_config_int(var,value);
 562         /* Also use aliases for command lookup */
 563         if (skip_prefix(var, "alias.", &p))
 564                 add_cmdname(&aliases, p, strlen(p));
 565
 566         return git_default_config(var, value, cb);
 567 }
 568
 569 static int levenshtein_compare(const void *p1, const void *p2)
 570 {
 571         const struct cmdname *const *c1 = p1, *const *c2 = p2;
 572         const char *s1 = (*c1)->name, *s2 = (*c2)->name;
 573         int l1 = (*c1)->len;
 574         int l2 = (*c2)->len;
 575         return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 576 }
 577
 578 static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 579 {
 580         int i;
 581         ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
 582
 583         for (i = 0; i < old->cnt; i++)
 584                 cmds->names[cmds->cnt++] = old->names[i];
 585         FREE_AND_NULL(old->names);
 586         old->cnt = 0;
 587 }
 588
 589 /* An empirically derived magic number */
 590 #define SIMILARITY_FLOOR 7
 591 #define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)
 592
 593 static const char bad_interpreter_advice[] =
 594         N_("'%s' appears to be a git command, but we were not\n"
 595         "able to execute it. Maybe git-%s is broken?");
 596
 597 const char *help_unknown_cmd(const char *cmd)
 598 {
 599         int i, n, best_similarity = 0;
 600         struct cmdnames main_cmds, other_cmds;
 601         struct cmdname_help *common_cmds;
 602
 603         memset(&main_cmds, 0, sizeof(main_cmds));
 604         memset(&other_cmds, 0, sizeof(other_cmds));
 605         memset(&aliases, 0, sizeof(aliases));
 606
 607         read_early_config(git_unknown_cmd_config, NULL);
 608
 609         load_command_list("git-", &main_cmds, &other_cmds);
 610
 611         add_cmd_list(&main_cmds, &aliases);
 612         add_cmd_list(&main_cmds, &other_cmds);
 613         QSORT(main_cmds.names, main_cmds.cnt, cmdname_compare);
 614         uniq(&main_cmds);
 615
 616         extract_cmds(&common_cmds, common_mask);
 617
 618         /* This abuses cmdname->len for levenshtein distance */
 619         for (i = 0, n = 0; i < main_cmds.cnt; i++) {
 620                 int cmp = 0; /* avoid compiler stupidity */
 621                 const char *candidate = main_cmds.names[i]->name;
 622
 623                 /*
 624                  * An exact match means we have the command, but
 625                  * for some reason exec'ing it gave us ENOENT; probably
 626                  * it's a bad interpreter in the #! line.
 627                  */
 628                 if (!strcmp(candidate, cmd))
 629                         die(_(bad_interpreter_advice), cmd, cmd);
 630
 631                 /* Does the candidate appear in common_cmds list? */
 632                 while (common_cmds[n].name &&
 633                        (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
 634                         n++;
 635                 if (common_cmds[n].name && !cmp) {
 636                         /* Yes, this is one of the common commands */
 637                         n++; /* use the entry from common_cmds[] */
 638                         if (starts_with(candidate, cmd)) {
 639                                 /* Give prefix match a very good score */
 640                                 main_cmds.names[i]->len = 0;
 641                                 continue;
 642                         }
 643                 }
 644
 645                 main_cmds.names[i]->len =
 646                         levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
 647         }
 648         FREE_AND_NULL(common_cmds);
 649
 650         QSORT(main_cmds.names, main_cmds.cnt, levenshtein_compare);
 651
 652         if (!main_cmds.cnt)
 653                 die(_("Uh oh. Your system reports no Git commands at all."));
 654
 655         /* skip and count prefix matches */
 656         for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
 657                 ; /* still counting */
 658
 659         if (main_cmds.cnt <= n) {
 660                 /* prefix matches with everything? that is too ambiguous */
 661                 best_similarity = SIMILARITY_FLOOR + 1;
 662         } else {
 663                 /* count all the most similar ones */
 664                 for (best_similarity = main_cmds.names[n++]->len;
 665                      (n < main_cmds.cnt &&
 666                       best_similarity == main_cmds.names[n]->len);
 667                      n++)
 668                         ; /* still counting */
 669         }
 670         if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
 671                 const char *assumed = main_cmds.names[0]->name;
 672                 main_cmds.names[0] = NULL;
 673                 clean_cmdnames(&main_cmds);
 674                 fprintf_ln(stderr,
 675                            _("WARNING: You called a Git command named '%s', "
 676                              "which does not exist."),
 677                            cmd);
 678                 if (autocorrect < 0)
 679                         fprintf_ln(stderr,
 680                                    _("Continuing under the assumption that "
 681                                      "you meant '%s'."),
 682                                    assumed);
 683                 else {
 684                         fprintf_ln(stderr,
 685                                    _("Continuing in %0.1f seconds, "
 686                                      "assuming that you meant '%s'."),
 687                                    (float)autocorrect/10.0, assumed);
 688                         sleep_millisec(autocorrect * 100);
 689                 }
 690                 return assumed;
 691         }
 692
 693         fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);
 694
 695         if (SIMILAR_ENOUGH(best_similarity)) {
 696                 fprintf_ln(stderr,
 697                            Q_("\nThe most similar command is",
 698                               "\nThe most similar commands are",
 699                            n));
 700
 701                 for (i = 0; i < n; i++)
 702                         fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 703         }
 704
 705         exit(1);
 706 }
 707
 708 int cmd_version(int argc, const char **argv, const char *prefix)
 709 {
 710         int build_options = 0;
 711         const char * const usage[] = {
 712                 N_("git version [<options>]"),
 713                 NULL
 714         };
 715         struct option options[] = {
 716                 OPT_BOOL(0, "build-options", &build_options,
 717                          "also print build options"),
 718                 OPT_END()
 719         };
 720
 721         argc = parse_options(argc, argv, prefix, options, usage, 0);
 722
 723         /*
 724          * The format of this string should be kept stable for compatibility
 725          * with external projects that rely on the output of "git version".
 726          *
 727          * Always show the version, even if other options are given.
 728          */
 729         printf("git version %s\n", git_version_string);
 730
 731         if (build_options) {
 732                 printf("cpu: %s\n", GIT_HOST_CPU);
 733                 if (git_built_from_commit_string[0])
 734                         printf("built from commit: %s\n",
 735                                git_built_from_commit_string);
 736                 else
 737                         printf("no commit associated with this build\n");
 738                 printf("sizeof-long: %d\n", (int)sizeof(long));
 739                 printf("sizeof-size_t: %d\n", (int)sizeof(size_t));
 740                 /* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
 741         }
 742         return 0;
 743 }
 744
 745 struct similar_ref_cb {
 746         const char *base_ref;
 747         struct string_list *similar_refs;
 748 };
 749
 750 static int append_similar_ref(const char *refname, const struct object_id *oid,
 751                               int flags, void *cb_data)
 752 {
 753         struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
 754         char *branch = strrchr(refname, '/') + 1;
 755         const char *remote;
 756
 757         /* A remote branch of the same name is deemed similar */
 758         if (skip_prefix(refname, "refs/remotes/", &remote) &&
 759             !strcmp(branch, cb->base_ref))
 760                 string_list_append(cb->similar_refs, remote);
 761         return 0;
 762 }
 763
 764 static struct string_list guess_refs(const char *ref)
 765 {
 766         struct similar_ref_cb ref_cb;
 767         struct string_list similar_refs = STRING_LIST_INIT_NODUP;
 768
 769         ref_cb.base_ref = ref;
 770         ref_cb.similar_refs = &similar_refs;
 771         for_each_ref(append_similar_ref, &ref_cb);
 772         return similar_refs;
 773 }
 774
 775 void help_unknown_ref(const char *ref, const char *cmd, const char *error)
 776 {
 777         int i;
 778         struct string_list suggested_refs = guess_refs(ref);
 779
 780         fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);
 781
 782         if (suggested_refs.nr > 0) {
 783                 fprintf_ln(stderr,
 784                            Q_("\nDid you mean this?",
 785                               "\nDid you mean one of these?",
 786                               suggested_refs.nr));
 787                 for (i = 0; i < suggested_refs.nr; i++)
 788                         fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
 789         }
 790
 791         string_list_clear(&suggested_refs, 0);
 792         exit(1);
 793 }