git.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "exec_cmd.h"
   4 #include "help.h"
   5 #include "run-command.h"
   6 #include "alias.h"
   7
   8 #define RUN_SETUP               (1<<0)
   9 #define RUN_SETUP_GENTLY        (1<<1)
  10 #define USE_PAGER               (1<<2)
  11 /*
  12  * require working tree to be present -- anything uses this needs
  13  * RUN_SETUP for reading from the configuration file.
  14  */
  15 #define NEED_WORK_TREE          (1<<3)
  16 #define SUPPORT_SUPER_PREFIX    (1<<4)
  17 #define DELAY_PAGER_CONFIG      (1<<5)
  18 #define NO_PARSEOPT             (1<<6) /* parse-options is not used */
  19
  20 struct cmd_struct {
  21         const char *cmd;
  22         int (*fn)(int, const char **, const char *);
  23         unsigned int option;
  24 };
  25
  26 const char git_usage_string[] =
  27         N_("git [--version] [--help] [-C <path>] [-c <name>=<value>]\n"
  28            "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  29            "           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
  30            "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  31            "           <command> [<args>]");
  32
  33 const char git_more_info_string[] =
  34         N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  35            "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  36            "to read about a specific subcommand or concept.");
  37
  38 static int use_pager = -1;
  39
  40 static void list_builtins(struct string_list *list, unsigned int exclude_option);
  41
  42 static void exclude_helpers_from_list(struct string_list *list)
  43 {
  44         int i = 0;
  45
  46         while (i < list->nr) {
  47                 if (strstr(list->items[i].string, "--"))
  48                         unsorted_string_list_delete_item(list, i, 0);
  49                 else
  50                         i++;
  51         }
  52 }
  53
  54 static int match_token(const char *spec, int len, const char *token)
  55 {
  56         int token_len = strlen(token);
  57
  58         return len == token_len && !strncmp(spec, token, token_len);
  59 }
  60
  61 static int list_cmds(const char *spec)
  62 {
  63         struct string_list list = STRING_LIST_INIT_DUP;
  64         int i;
  65
  66         while (*spec) {
  67                 const char *sep = strchrnul(spec, ',');
  68                 int len = sep - spec;
  69
  70                 if (match_token(spec, len, "builtins"))
  71                         list_builtins(&list, 0);
  72                 else if (match_token(spec, len, "main"))
  73                         list_all_main_cmds(&list);
  74                 else if (match_token(spec, len, "others"))
  75                         list_all_other_cmds(&list);
  76                 else if (match_token(spec, len, "nohelpers"))
  77                         exclude_helpers_from_list(&list);
  78                 else if (match_token(spec, len, "alias"))
  79                         list_aliases(&list);
  80                 else if (len > 5 && !strncmp(spec, "list-", 5)) {
  81                         struct strbuf sb = STRBUF_INIT;
  82
  83                         strbuf_add(&sb, spec + 5, len - 5);
  84                         list_cmds_by_category(&list, sb.buf);
  85                         strbuf_release(&sb);
  86                 }
  87                 else
  88                         die(_("unsupported command listing type '%s'"), spec);
  89                 spec += len;
  90                 if (*spec == ',')
  91                         spec++;
  92         }
  93         for (i = 0; i < list.nr; i++)
  94                 puts(list.items[i].string);
  95         string_list_clear(&list, 0);
  96         return 0;
  97 }
  98
  99 static void commit_pager_choice(void) {
 100         switch (use_pager) {
 101         case 0:
 102                 setenv("GIT_PAGER", "cat", 1);
 103                 break;
 104         case 1:
 105                 setup_pager();
 106                 break;
 107         default:
 108                 break;
 109         }
 110 }
 111
 112 void setup_auto_pager(const char *cmd, int def)
 113 {
 114         if (use_pager != -1 || pager_in_use())
 115                 return;
 116         use_pager = check_pager_config(cmd);
 117         if (use_pager == -1)
 118                 use_pager = def;
 119         commit_pager_choice();
 120 }
 121
 122 static int handle_options(const char ***argv, int *argc, int *envchanged)
 123 {
 124         const char **orig_argv = *argv;
 125
 126         while (*argc > 0) {
 127                 const char *cmd = (*argv)[0];
 128                 if (cmd[0] != '-')
 129                         break;
 130
 131                 /*
 132                  * For legacy reasons, the "version" and "help"
 133                  * commands can be written with "--" prepended
 134                  * to make them look like flags.
 135                  */
 136                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 137                         break;
 138
 139                 /*
 140                  * Check remaining flags.
 141                  */
 142                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
 143                         if (*cmd == '=')
 144                                 git_set_argv_exec_path(cmd + 1);
 145                         else {
 146                                 puts(git_exec_path());
 147                                 exit(0);
 148                         }
 149                 } else if (!strcmp(cmd, "--html-path")) {
 150                         puts(system_path(GIT_HTML_PATH));
 151                         exit(0);
 152                 } else if (!strcmp(cmd, "--man-path")) {
 153                         puts(system_path(GIT_MAN_PATH));
 154                         exit(0);
 155                 } else if (!strcmp(cmd, "--info-path")) {
 156                         puts(system_path(GIT_INFO_PATH));
 157                         exit(0);
 158                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 159                         use_pager = 1;
 160                 } else if (!strcmp(cmd, "--no-pager")) {
 161                         use_pager = 0;
 162                         if (envchanged)
 163                                 *envchanged = 1;
 164                 } else if (!strcmp(cmd, "--no-replace-objects")) {
 165                         check_replace_refs = 0;
 166                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 167                         if (envchanged)
 168                                 *envchanged = 1;
 169                 } else if (!strcmp(cmd, "--git-dir")) {
 170                         if (*argc < 2) {
 171                                 fprintf(stderr, _("no directory given for --git-dir\n" ));
 172                                 usage(git_usage_string);
 173                         }
 174                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 175                         if (envchanged)
 176                                 *envchanged = 1;
 177                         (*argv)++;
 178                         (*argc)--;
 179                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 180                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 181                         if (envchanged)
 182                                 *envchanged = 1;
 183                 } else if (!strcmp(cmd, "--namespace")) {
 184                         if (*argc < 2) {
 185                                 fprintf(stderr, _("no namespace given for --namespace\n" ));
 186                                 usage(git_usage_string);
 187                         }
 188                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 189                         if (envchanged)
 190                                 *envchanged = 1;
 191                         (*argv)++;
 192                         (*argc)--;
 193                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 194                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 195                         if (envchanged)
 196                                 *envchanged = 1;
 197                 } else if (!strcmp(cmd, "--work-tree")) {
 198                         if (*argc < 2) {
 199                                 fprintf(stderr, _("no directory given for --work-tree\n" ));
 200                                 usage(git_usage_string);
 201                         }
 202                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 203                         if (envchanged)
 204                                 *envchanged = 1;
 205                         (*argv)++;
 206                         (*argc)--;
 207                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 208                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 209                         if (envchanged)
 210                                 *envchanged = 1;
 211                 } else if (!strcmp(cmd, "--super-prefix")) {
 212                         if (*argc < 2) {
 213                                 fprintf(stderr, _("no prefix given for --super-prefix\n" ));
 214                                 usage(git_usage_string);
 215                         }
 216                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 217                         if (envchanged)
 218                                 *envchanged = 1;
 219                         (*argv)++;
 220                         (*argc)--;
 221                 } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 222                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 223                         if (envchanged)
 224                                 *envchanged = 1;
 225                 } else if (!strcmp(cmd, "--bare")) {
 226                         char *cwd = xgetcwd();
 227                         is_bare_repository_cfg = 1;
 228                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 229                         free(cwd);
 230                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 231                         if (envchanged)
 232                                 *envchanged = 1;
 233                 } else if (!strcmp(cmd, "-c")) {
 234                         if (*argc < 2) {
 235                                 fprintf(stderr, _("-c expects a configuration string\n" ));
 236                                 usage(git_usage_string);
 237                         }
 238                         git_config_push_parameter((*argv)[1]);
 239                         (*argv)++;
 240                         (*argc)--;
 241                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
 242                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 243                         if (envchanged)
 244                                 *envchanged = 1;
 245                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 246                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 247                         if (envchanged)
 248                                 *envchanged = 1;
 249                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
 250                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 251                         if (envchanged)
 252                                 *envchanged = 1;
 253                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 254                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 255                         if (envchanged)
 256                                 *envchanged = 1;
 257                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
 258                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 259                         if (envchanged)
 260                                 *envchanged = 1;
 261                 } else if (!strcmp(cmd, "--no-optional-locks")) {
 262                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 263                         if (envchanged)
 264                                 *envchanged = 1;
 265                 } else if (!strcmp(cmd, "--shallow-file")) {
 266                         (*argv)++;
 267                         (*argc)--;
 268                         set_alternate_shallow_file((*argv)[0], 1);
 269                         if (envchanged)
 270                                 *envchanged = 1;
 271                 } else if (!strcmp(cmd, "-C")) {
 272                         if (*argc < 2) {
 273                                 fprintf(stderr, _("no directory given for -C\n" ));
 274                                 usage(git_usage_string);
 275                         }
 276                         if ((*argv)[1][0]) {
 277                                 if (chdir((*argv)[1]))
 278                                         die_errno("cannot change to '%s'", (*argv)[1]);
 279                                 if (envchanged)
 280                                         *envchanged = 1;
 281                         }
 282                         (*argv)++;
 283                         (*argc)--;
 284                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 285                         if (!strcmp(cmd, "parseopt")) {
 286                                 struct string_list list = STRING_LIST_INIT_DUP;
 287                                 int i;
 288
 289                                 list_builtins(&list, NO_PARSEOPT);
 290                                 for (i = 0; i < list.nr; i++)
 291                                         printf("%s ", list.items[i].string);
 292                                 string_list_clear(&list, 0);
 293                                 exit(0);
 294                         } else {
 295                                 exit(list_cmds(cmd));
 296                         }
 297                 } else {
 298                         fprintf(stderr, _("unknown option: %s\n"), cmd);
 299                         usage(git_usage_string);
 300                 }
 301
 302                 (*argv)++;
 303                 (*argc)--;
 304         }
 305         return (*argv) - orig_argv;
 306 }
 307
 308 static int handle_alias(int *argcp, const char ***argv)
 309 {
 310         int envchanged = 0, ret = 0, saved_errno = errno;
 311         int count, option_count;
 312         const char **new_argv;
 313         const char *alias_command;
 314         char *alias_string;
 315
 316         alias_command = (*argv)[0];
 317         alias_string = alias_lookup(alias_command);
 318         if (alias_string) {
 319                 if (alias_string[0] == '!') {
 320                         struct child_process child = CHILD_PROCESS_INIT;
 321                         int nongit_ok;
 322
 323                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 324                         setup_git_directory_gently(&nongit_ok);
 325
 326                         commit_pager_choice();
 327
 328                         child.use_shell = 1;
 329                         argv_array_push(&child.args, alias_string + 1);
 330                         argv_array_pushv(&child.args, (*argv) + 1);
 331
 332                         ret = run_command(&child);
 333                         if (ret >= 0)   /* normal exit */
 334                                 exit(ret);
 335
 336                         die_errno("while expanding alias '%s': '%s'",
 337                             alias_command, alias_string + 1);
 338                 }
 339                 count = split_cmdline(alias_string, &new_argv);
 340                 if (count < 0)
 341                         die("Bad alias.%s string: %s", alias_command,
 342                             split_cmdline_strerror(count));
 343                 option_count = handle_options(&new_argv, &count, &envchanged);
 344                 if (envchanged)
 345                         die("alias '%s' changes environment variables.\n"
 346                                  "You can use '!git' in the alias to do this",
 347                                  alias_command);
 348                 memmove(new_argv - option_count, new_argv,
 349                                 count * sizeof(char *));
 350                 new_argv -= option_count;
 351
 352                 if (count < 1)
 353                         die("empty alias for %s", alias_command);
 354
 355                 if (!strcmp(alias_command, new_argv[0]))
 356                         die("recursive alias: %s", alias_command);
 357
 358                 trace_argv_printf(new_argv,
 359                                   "trace: alias expansion: %s =>",
 360                                   alias_command);
 361
 362                 REALLOC_ARRAY(new_argv, count + *argcp);
 363                 /* insert after command name */
 364                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 365
 366                 *argv = new_argv;
 367                 *argcp += count - 1;
 368
 369                 ret = 1;
 370         }
 371
 372         errno = saved_errno;
 373
 374         return ret;
 375 }
 376
 377 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 378 {
 379         int status, help;
 380         struct stat st;
 381         const char *prefix;
 382
 383         prefix = NULL;
 384         help = argc == 2 && !strcmp(argv[1], "-h");
 385         if (!help) {
 386                 if (p->option & RUN_SETUP)
 387                         prefix = setup_git_directory();
 388                 else if (p->option & RUN_SETUP_GENTLY) {
 389                         int nongit_ok;
 390                         prefix = setup_git_directory_gently(&nongit_ok);
 391                 }
 392
 393                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
 394                     !(p->option & DELAY_PAGER_CONFIG))
 395                         use_pager = check_pager_config(p->cmd);
 396                 if (use_pager == -1 && p->option & USE_PAGER)
 397                         use_pager = 1;
 398
 399                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 400                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 401                         trace_repo_setup(prefix);
 402         }
 403         commit_pager_choice();
 404
 405         if (!help && get_super_prefix()) {
 406                 if (!(p->option & SUPPORT_SUPER_PREFIX))
 407                         die("%s doesn't support --super-prefix", p->cmd);
 408         }
 409
 410         if (!help && p->option & NEED_WORK_TREE)
 411                 setup_work_tree();
 412
 413         trace_argv_printf(argv, "trace: built-in: git");
 414
 415         status = p->fn(argc, argv, prefix);
 416         if (status)
 417                 return status;
 418
 419         /* Somebody closed stdout? */
 420         if (fstat(fileno(stdout), &st))
 421                 return 0;
 422         /* Ignore write errors for pipes and sockets.. */
 423         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 424                 return 0;
 425
 426         /* Check for ENOSPC and EIO errors.. */
 427         if (fflush(stdout))
 428                 die_errno("write failure on standard output");
 429         if (ferror(stdout))
 430                 die("unknown write failure on standard output");
 431         if (fclose(stdout))
 432                 die_errno("close failed on standard output");
 433         return 0;
 434 }
 435
 436 static struct cmd_struct commands[] = {
 437         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 438         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 439         { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
 440         { "apply", cmd_apply, RUN_SETUP_GENTLY },
 441         { "archive", cmd_archive, RUN_SETUP_GENTLY },
 442         { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 443         { "blame", cmd_blame, RUN_SETUP },
 444         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 445         { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
 446         { "cat-file", cmd_cat_file, RUN_SETUP },
 447         { "check-attr", cmd_check_attr, RUN_SETUP },
 448         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 449         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 450         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 451         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 452         { "checkout-index", cmd_checkout_index,
 453                 RUN_SETUP | NEED_WORK_TREE},
 454         { "cherry", cmd_cherry, RUN_SETUP },
 455         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 456         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 457         { "clone", cmd_clone },
 458         { "column", cmd_column, RUN_SETUP_GENTLY },
 459         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 460         { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
 461         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 462         { "count-objects", cmd_count_objects, RUN_SETUP },
 463         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 464         { "describe", cmd_describe, RUN_SETUP },
 465         { "diff", cmd_diff, NO_PARSEOPT },
 466         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 467         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 468         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 469         { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 470         { "fast-export", cmd_fast_export, RUN_SETUP },
 471         { "fetch", cmd_fetch, RUN_SETUP },
 472         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 473         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 474         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 475         { "format-patch", cmd_format_patch, RUN_SETUP },
 476         { "fsck", cmd_fsck, RUN_SETUP },
 477         { "fsck-objects", cmd_fsck, RUN_SETUP },
 478         { "gc", cmd_gc, RUN_SETUP },
 479         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 480         { "grep", cmd_grep, RUN_SETUP_GENTLY },
 481         { "hash-object", cmd_hash_object },
 482         { "help", cmd_help },
 483         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 484         { "init", cmd_init_db },
 485         { "init-db", cmd_init_db },
 486         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 487         { "log", cmd_log, RUN_SETUP },
 488         { "ls-files", cmd_ls_files, RUN_SETUP },
 489         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 490         { "ls-tree", cmd_ls_tree, RUN_SETUP },
 491         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
 492         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 493         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 494         { "merge-base", cmd_merge_base, RUN_SETUP },
 495         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 496         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 497         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 498         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 499         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 500         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 501         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 502         { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
 503         { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
 504         { "mktree", cmd_mktree, RUN_SETUP },
 505         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 506         { "name-rev", cmd_name_rev, RUN_SETUP },
 507         { "notes", cmd_notes, RUN_SETUP },
 508         { "pack-objects", cmd_pack_objects, RUN_SETUP },
 509         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 510         { "pack-refs", cmd_pack_refs, RUN_SETUP },
 511         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 512         { "pickaxe", cmd_blame, RUN_SETUP },
 513         { "prune", cmd_prune, RUN_SETUP },
 514         { "prune-packed", cmd_prune_packed, RUN_SETUP },
 515         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 516         { "push", cmd_push, RUN_SETUP },
 517         { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 518         { "rebase--helper", cmd_rebase__helper, RUN_SETUP | NEED_WORK_TREE },
 519         { "receive-pack", cmd_receive_pack },
 520         { "reflog", cmd_reflog, RUN_SETUP },
 521         { "remote", cmd_remote, RUN_SETUP },
 522         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 523         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 524         { "repack", cmd_repack, RUN_SETUP },
 525         { "replace", cmd_replace, RUN_SETUP },
 526         { "rerere", cmd_rerere, RUN_SETUP },
 527         { "reset", cmd_reset, RUN_SETUP },
 528         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 529         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 530         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 531         { "rm", cmd_rm, RUN_SETUP },
 532         { "send-pack", cmd_send_pack, RUN_SETUP },
 533         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 534         { "show", cmd_show, RUN_SETUP },
 535         { "show-branch", cmd_show_branch, RUN_SETUP },
 536         { "show-ref", cmd_show_ref, RUN_SETUP },
 537         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 538         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 539         { "stripspace", cmd_stripspace },
 540         { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
 541         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 542         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 543         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 544         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 545         { "update-index", cmd_update_index, RUN_SETUP },
 546         { "update-ref", cmd_update_ref, RUN_SETUP },
 547         { "update-server-info", cmd_update_server_info, RUN_SETUP },
 548         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 549         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 550         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 551         { "verify-commit", cmd_verify_commit, RUN_SETUP },
 552         { "verify-pack", cmd_verify_pack },
 553         { "verify-tag", cmd_verify_tag, RUN_SETUP },
 554         { "version", cmd_version },
 555         { "whatchanged", cmd_whatchanged, RUN_SETUP },
 556         { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
 557         { "write-tree", cmd_write_tree, RUN_SETUP },
 558 };
 559
 560 static struct cmd_struct *get_builtin(const char *s)
 561 {
 562         int i;
 563         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 564                 struct cmd_struct *p = commands + i;
 565                 if (!strcmp(s, p->cmd))
 566                         return p;
 567         }
 568         return NULL;
 569 }
 570
 571 int is_builtin(const char *s)
 572 {
 573         return !!get_builtin(s);
 574 }
 575
 576 static void list_builtins(struct string_list *out, unsigned int exclude_option)
 577 {
 578         int i;
 579         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 580                 if (exclude_option &&
 581                     (commands[i].option & exclude_option))
 582                         continue;
 583                 string_list_append(out, commands[i].cmd);
 584         }
 585 }
 586
 587 #ifdef STRIP_EXTENSION
 588 static void strip_extension(const char **argv)
 589 {
 590         size_t len;
 591
 592         if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 593                 argv[0] = xmemdupz(argv[0], len);
 594 }
 595 #else
 596 #define strip_extension(cmd)
 597 #endif
 598
 599 static void handle_builtin(int argc, const char **argv)
 600 {
 601         struct argv_array args = ARGV_ARRAY_INIT;
 602         const char *cmd;
 603         struct cmd_struct *builtin;
 604
 605         strip_extension(argv);
 606         cmd = argv[0];
 607
 608         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 609         if (argc > 1 && !strcmp(argv[1], "--help")) {
 610                 int i;
 611
 612                 argv[1] = argv[0];
 613                 argv[0] = cmd = "help";
 614
 615                 for (i = 0; i < argc; i++) {
 616                         argv_array_push(&args, argv[i]);
 617                         if (!i)
 618                                 argv_array_push(&args, "--exclude-guides");
 619                 }
 620
 621                 argc++;
 622                 argv = args.argv;
 623         }
 624
 625         builtin = get_builtin(cmd);
 626         if (builtin)
 627                 exit(run_builtin(builtin, argc, argv));
 628         argv_array_clear(&args);
 629 }
 630
 631 static void execv_dashed_external(const char **argv)
 632 {
 633         struct child_process cmd = CHILD_PROCESS_INIT;
 634         int status;
 635
 636         if (get_super_prefix())
 637                 die("%s doesn't support --super-prefix", argv[0]);
 638
 639         if (use_pager == -1 && !is_builtin(argv[0]))
 640                 use_pager = check_pager_config(argv[0]);
 641         commit_pager_choice();
 642
 643         argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 644         argv_array_pushv(&cmd.args, argv + 1);
 645         cmd.clean_on_exit = 1;
 646         cmd.wait_after_clean = 1;
 647         cmd.silent_exec_failure = 1;
 648
 649         trace_argv_printf(cmd.args.argv, "trace: exec:");
 650
 651         /*
 652          * If we fail because the command is not found, it is
 653          * OK to return. Otherwise, we just pass along the status code,
 654          * or our usual generic code if we were not even able to exec
 655          * the program.
 656          */
 657         status = run_command(&cmd);
 658         if (status >= 0)
 659                 exit(status);
 660         else if (errno != ENOENT)
 661                 exit(128);
 662 }
 663
 664 static int run_argv(int *argcp, const char ***argv)
 665 {
 666         int done_alias = 0;
 667
 668         while (1) {
 669                 /*
 670                  * If we tried alias and futzed with our environment,
 671                  * it no longer is safe to invoke builtins directly in
 672                  * general.  We have to spawn them as dashed externals.
 673                  *
 674                  * NEEDSWORK: if we can figure out cases
 675                  * where it is safe to do, we can avoid spawning a new
 676                  * process.
 677                  */
 678                 if (!done_alias)
 679                         handle_builtin(*argcp, *argv);
 680
 681                 /* .. then try the external ones */
 682                 execv_dashed_external(*argv);
 683
 684                 /* It could be an alias -- this works around the insanity
 685                  * of overriding "git log" with "git show" by having
 686                  * alias.log = show
 687                  */
 688                 if (done_alias)
 689                         break;
 690                 if (!handle_alias(argcp, argv))
 691                         break;
 692                 done_alias = 1;
 693         }
 694
 695         return done_alias;
 696 }
 697
 698 int cmd_main(int argc, const char **argv)
 699 {
 700         const char *cmd;
 701         int done_help = 0;
 702
 703         cmd = argv[0];
 704         if (!cmd)
 705                 cmd = "git-help";
 706         else {
 707                 const char *slash = find_last_dir_sep(cmd);
 708                 if (slash)
 709                         cmd = slash + 1;
 710         }
 711
 712         trace_command_performance(argv);
 713
 714         /*
 715          * "git-xxxx" is the same as "git xxxx", but we obviously:
 716          *
 717          *  - cannot take flags in between the "git" and the "xxxx".
 718          *  - cannot execute it externally (since it would just do
 719          *    the same thing over again)
 720          *
 721          * So we just directly call the builtin handler, and die if
 722          * that one cannot handle it.
 723          */
 724         if (skip_prefix(cmd, "git-", &cmd)) {
 725                 argv[0] = cmd;
 726                 handle_builtin(argc, argv);
 727                 die("cannot handle %s as a builtin", cmd);
 728         }
 729
 730         /* Look for flags.. */
 731         argv++;
 732         argc--;
 733         handle_options(&argv, &argc, NULL);
 734         if (argc > 0) {
 735                 /* translate --help and --version into commands */
 736                 skip_prefix(argv[0], "--", &argv[0]);
 737         } else {
 738                 /* The user didn't specify a command; give them help */
 739                 commit_pager_choice();
 740                 printf("usage: %s\n\n", git_usage_string);
 741                 list_common_cmds_help();
 742                 printf("\n%s\n", _(git_more_info_string));
 743                 exit(1);
 744         }
 745         cmd = argv[0];
 746
 747         /*
 748          * We use PATH to find git commands, but we prepend some higher
 749          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 750          * environment, and the $(gitexecdir) from the Makefile at build
 751          * time.
 752          */
 753         setup_path();
 754
 755         while (1) {
 756                 int was_alias = run_argv(&argc, &argv);
 757                 if (errno != ENOENT)
 758                         break;
 759                 if (was_alias) {
 760                         fprintf(stderr, _("expansion of alias '%s' failed; "
 761                                           "'%s' is not a git command\n"),
 762                                 cmd, argv[0]);
 763                         exit(1);
 764                 }
 765                 if (!done_help) {
 766                         cmd = argv[0] = help_unknown_cmd(cmd);
 767                         done_help = 1;
 768                 } else
 769                         break;
 770         }
 771
 772         fprintf(stderr, _("failed to run command '%s': %s\n"),
 773                 cmd, strerror(errno));
 774
 775         return 1;
 776 }