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 | -P | --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 (match_token(spec, len, "config"))
  81                         list_cmds_by_config(&list);
  82                 else if (len > 5 && !strncmp(spec, "list-", 5)) {
  83                         struct strbuf sb = STRBUF_INIT;
  84
  85                         strbuf_add(&sb, spec + 5, len - 5);
  86                         list_cmds_by_category(&list, sb.buf);
  87                         strbuf_release(&sb);
  88                 }
  89                 else
  90                         die(_("unsupported command listing type '%s'"), spec);
  91                 spec += len;
  92                 if (*spec == ',')
  93                         spec++;
  94         }
  95         for (i = 0; i < list.nr; i++)
  96                 puts(list.items[i].string);
  97         string_list_clear(&list, 0);
  98         return 0;
  99 }
 100
 101 static void commit_pager_choice(void)
 102 {
 103         switch (use_pager) {
 104         case 0:
 105                 setenv("GIT_PAGER", "cat", 1);
 106                 break;
 107         case 1:
 108                 setup_pager();
 109                 break;
 110         default:
 111                 break;
 112         }
 113 }
 114
 115 void setup_auto_pager(const char *cmd, int def)
 116 {
 117         if (use_pager != -1 || pager_in_use())
 118                 return;
 119         use_pager = check_pager_config(cmd);
 120         if (use_pager == -1)
 121                 use_pager = def;
 122         commit_pager_choice();
 123 }
 124
 125 static int handle_options(const char ***argv, int *argc, int *envchanged)
 126 {
 127         const char **orig_argv = *argv;
 128
 129         while (*argc > 0) {
 130                 const char *cmd = (*argv)[0];
 131                 if (cmd[0] != '-')
 132                         break;
 133
 134                 /*
 135                  * For legacy reasons, the "version" and "help"
 136                  * commands can be written with "--" prepended
 137                  * to make them look like flags.
 138                  */
 139                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 140                         break;
 141
 142                 /*
 143                  * Check remaining flags.
 144                  */
 145                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
 146                         if (*cmd == '=')
 147                                 git_set_exec_path(cmd + 1);
 148                         else {
 149                                 puts(git_exec_path());
 150                                 exit(0);
 151                         }
 152                 } else if (!strcmp(cmd, "--html-path")) {
 153                         puts(system_path(GIT_HTML_PATH));
 154                         exit(0);
 155                 } else if (!strcmp(cmd, "--man-path")) {
 156                         puts(system_path(GIT_MAN_PATH));
 157                         exit(0);
 158                 } else if (!strcmp(cmd, "--info-path")) {
 159                         puts(system_path(GIT_INFO_PATH));
 160                         exit(0);
 161                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 162                         use_pager = 1;
 163                 } else if (!strcmp(cmd, "-P") || !strcmp(cmd, "--no-pager")) {
 164                         use_pager = 0;
 165                         if (envchanged)
 166                                 *envchanged = 1;
 167                 } else if (!strcmp(cmd, "--no-replace-objects")) {
 168                         read_replace_refs = 0;
 169                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 170                         if (envchanged)
 171                                 *envchanged = 1;
 172                 } else if (!strcmp(cmd, "--git-dir")) {
 173                         if (*argc < 2) {
 174                                 fprintf(stderr, _("no directory given for --git-dir\n" ));
 175                                 usage(git_usage_string);
 176                         }
 177                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 178                         if (envchanged)
 179                                 *envchanged = 1;
 180                         (*argv)++;
 181                         (*argc)--;
 182                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 183                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 184                         if (envchanged)
 185                                 *envchanged = 1;
 186                 } else if (!strcmp(cmd, "--namespace")) {
 187                         if (*argc < 2) {
 188                                 fprintf(stderr, _("no namespace given for --namespace\n" ));
 189                                 usage(git_usage_string);
 190                         }
 191                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 192                         if (envchanged)
 193                                 *envchanged = 1;
 194                         (*argv)++;
 195                         (*argc)--;
 196                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 197                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 198                         if (envchanged)
 199                                 *envchanged = 1;
 200                 } else if (!strcmp(cmd, "--work-tree")) {
 201                         if (*argc < 2) {
 202                                 fprintf(stderr, _("no directory given for --work-tree\n" ));
 203                                 usage(git_usage_string);
 204                         }
 205                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 206                         if (envchanged)
 207                                 *envchanged = 1;
 208                         (*argv)++;
 209                         (*argc)--;
 210                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 211                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 212                         if (envchanged)
 213                                 *envchanged = 1;
 214                 } else if (!strcmp(cmd, "--super-prefix")) {
 215                         if (*argc < 2) {
 216                                 fprintf(stderr, _("no prefix given for --super-prefix\n" ));
 217                                 usage(git_usage_string);
 218                         }
 219                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 220                         if (envchanged)
 221                                 *envchanged = 1;
 222                         (*argv)++;
 223                         (*argc)--;
 224                 } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 225                         setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 226                         if (envchanged)
 227                                 *envchanged = 1;
 228                 } else if (!strcmp(cmd, "--bare")) {
 229                         char *cwd = xgetcwd();
 230                         is_bare_repository_cfg = 1;
 231                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 232                         free(cwd);
 233                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 234                         if (envchanged)
 235                                 *envchanged = 1;
 236                 } else if (!strcmp(cmd, "-c")) {
 237                         if (*argc < 2) {
 238                                 fprintf(stderr, _("-c expects a configuration string\n" ));
 239                                 usage(git_usage_string);
 240                         }
 241                         git_config_push_parameter((*argv)[1]);
 242                         (*argv)++;
 243                         (*argc)--;
 244                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
 245                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 246                         if (envchanged)
 247                                 *envchanged = 1;
 248                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 249                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 250                         if (envchanged)
 251                                 *envchanged = 1;
 252                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
 253                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 254                         if (envchanged)
 255                                 *envchanged = 1;
 256                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 257                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 258                         if (envchanged)
 259                                 *envchanged = 1;
 260                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
 261                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 262                         if (envchanged)
 263                                 *envchanged = 1;
 264                 } else if (!strcmp(cmd, "--no-optional-locks")) {
 265                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 266                         if (envchanged)
 267                                 *envchanged = 1;
 268                 } else if (!strcmp(cmd, "--shallow-file")) {
 269                         (*argv)++;
 270                         (*argc)--;
 271                         set_alternate_shallow_file(the_repository, (*argv)[0], 1);
 272                         if (envchanged)
 273                                 *envchanged = 1;
 274                 } else if (!strcmp(cmd, "-C")) {
 275                         if (*argc < 2) {
 276                                 fprintf(stderr, _("no directory given for -C\n" ));
 277                                 usage(git_usage_string);
 278                         }
 279                         if ((*argv)[1][0]) {
 280                                 if (chdir((*argv)[1]))
 281                                         die_errno("cannot change to '%s'", (*argv)[1]);
 282                                 if (envchanged)
 283                                         *envchanged = 1;
 284                         }
 285                         (*argv)++;
 286                         (*argc)--;
 287                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 288                         if (!strcmp(cmd, "parseopt")) {
 289                                 struct string_list list = STRING_LIST_INIT_DUP;
 290                                 int i;
 291
 292                                 list_builtins(&list, NO_PARSEOPT);
 293                                 for (i = 0; i < list.nr; i++)
 294                                         printf("%s ", list.items[i].string);
 295                                 string_list_clear(&list, 0);
 296                                 exit(0);
 297                         } else {
 298                                 exit(list_cmds(cmd));
 299                         }
 300                 } else {
 301                         fprintf(stderr, _("unknown option: %s\n"), cmd);
 302                         usage(git_usage_string);
 303                 }
 304
 305                 (*argv)++;
 306                 (*argc)--;
 307         }
 308         return (*argv) - orig_argv;
 309 }
 310
 311 static int handle_alias(int *argcp, const char ***argv)
 312 {
 313         int envchanged = 0, ret = 0, saved_errno = errno;
 314         int count, option_count;
 315         const char **new_argv;
 316         const char *alias_command;
 317         char *alias_string;
 318
 319         alias_command = (*argv)[0];
 320         alias_string = alias_lookup(alias_command);
 321         if (alias_string) {
 322                 if (*argcp > 1 && !strcmp((*argv)[1], "-h"))
 323                         fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
 324                                    alias_command, alias_string);
 325                 if (alias_string[0] == '!') {
 326                         struct child_process child = CHILD_PROCESS_INIT;
 327                         int nongit_ok;
 328
 329                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 330                         setup_git_directory_gently(&nongit_ok);
 331
 332                         commit_pager_choice();
 333
 334                         child.use_shell = 1;
 335                         argv_array_push(&child.args, alias_string + 1);
 336                         argv_array_pushv(&child.args, (*argv) + 1);
 337
 338                         ret = run_command(&child);
 339                         if (ret >= 0)   /* normal exit */
 340                                 exit(ret);
 341
 342                         die_errno(_("while expanding alias '%s': '%s'"),
 343                                   alias_command, alias_string + 1);
 344                 }
 345                 count = split_cmdline(alias_string, &new_argv);
 346                 if (count < 0)
 347                         die(_("bad alias.%s string: %s"), alias_command,
 348                             _(split_cmdline_strerror(count)));
 349                 option_count = handle_options(&new_argv, &count, &envchanged);
 350                 if (envchanged)
 351                         die(_("alias '%s' changes environment variables.\n"
 352                               "You can use '!git' in the alias to do this"),
 353                             alias_command);
 354                 memmove(new_argv - option_count, new_argv,
 355                                 count * sizeof(char *));
 356                 new_argv -= option_count;
 357
 358                 if (count < 1)
 359                         die(_("empty alias for %s"), alias_command);
 360
 361                 if (!strcmp(alias_command, new_argv[0]))
 362                         die(_("recursive alias: %s"), alias_command);
 363
 364                 trace_argv_printf(new_argv,
 365                                   "trace: alias expansion: %s =>",
 366                                   alias_command);
 367
 368                 REALLOC_ARRAY(new_argv, count + *argcp);
 369                 /* insert after command name */
 370                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 371
 372                 *argv = new_argv;
 373                 *argcp += count - 1;
 374
 375                 ret = 1;
 376         }
 377
 378         errno = saved_errno;
 379
 380         return ret;
 381 }
 382
 383 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 384 {
 385         int status, help;
 386         struct stat st;
 387         const char *prefix;
 388
 389         prefix = NULL;
 390         help = argc == 2 && !strcmp(argv[1], "-h");
 391         if (!help) {
 392                 if (p->option & RUN_SETUP)
 393                         prefix = setup_git_directory();
 394                 else if (p->option & RUN_SETUP_GENTLY) {
 395                         int nongit_ok;
 396                         prefix = setup_git_directory_gently(&nongit_ok);
 397                 }
 398
 399                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
 400                     !(p->option & DELAY_PAGER_CONFIG))
 401                         use_pager = check_pager_config(p->cmd);
 402                 if (use_pager == -1 && p->option & USE_PAGER)
 403                         use_pager = 1;
 404
 405                 if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 406                     startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 407                         trace_repo_setup(prefix);
 408         }
 409         commit_pager_choice();
 410
 411         if (!help && get_super_prefix()) {
 412                 if (!(p->option & SUPPORT_SUPER_PREFIX))
 413                         die(_("%s doesn't support --super-prefix"), p->cmd);
 414         }
 415
 416         if (!help && p->option & NEED_WORK_TREE)
 417                 setup_work_tree();
 418
 419         trace_argv_printf(argv, "trace: built-in: git");
 420
 421         validate_cache_entries(the_repository->index);
 422         status = p->fn(argc, argv, prefix);
 423         validate_cache_entries(the_repository->index);
 424
 425         if (status)
 426                 return status;
 427
 428         /* Somebody closed stdout? */
 429         if (fstat(fileno(stdout), &st))
 430                 return 0;
 431         /* Ignore write errors for pipes and sockets.. */
 432         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 433                 return 0;
 434
 435         /* Check for ENOSPC and EIO errors.. */
 436         if (fflush(stdout))
 437                 die_errno(_("write failure on standard output"));
 438         if (ferror(stdout))
 439                 die(_("unknown write failure on standard output"));
 440         if (fclose(stdout))
 441                 die_errno(_("close failed on standard output"));
 442         return 0;
 443 }
 444
 445 static struct cmd_struct commands[] = {
 446         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 447         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 448         { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
 449         { "apply", cmd_apply, RUN_SETUP_GENTLY },
 450         { "archive", cmd_archive, RUN_SETUP_GENTLY },
 451         { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 452         { "blame", cmd_blame, RUN_SETUP },
 453         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 454         { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
 455         { "cat-file", cmd_cat_file, RUN_SETUP },
 456         { "check-attr", cmd_check_attr, RUN_SETUP },
 457         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 458         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 459         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 460         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 461         { "checkout-index", cmd_checkout_index,
 462                 RUN_SETUP | NEED_WORK_TREE},
 463         { "cherry", cmd_cherry, RUN_SETUP },
 464         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 465         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 466         { "clone", cmd_clone },
 467         { "column", cmd_column, RUN_SETUP_GENTLY },
 468         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 469         { "commit-graph", cmd_commit_graph, RUN_SETUP },
 470         { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
 471         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 472         { "count-objects", cmd_count_objects, RUN_SETUP },
 473         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 474         { "describe", cmd_describe, RUN_SETUP },
 475         { "diff", cmd_diff, NO_PARSEOPT },
 476         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 477         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 478         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 479         { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 480         { "fast-export", cmd_fast_export, RUN_SETUP },
 481         { "fetch", cmd_fetch, RUN_SETUP },
 482         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 483         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 484         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 485         { "format-patch", cmd_format_patch, RUN_SETUP },
 486         { "fsck", cmd_fsck, RUN_SETUP },
 487         { "fsck-objects", cmd_fsck, RUN_SETUP },
 488         { "gc", cmd_gc, RUN_SETUP },
 489         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 490         { "grep", cmd_grep, RUN_SETUP_GENTLY },
 491         { "hash-object", cmd_hash_object },
 492         { "help", cmd_help },
 493         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 494         { "init", cmd_init_db },
 495         { "init-db", cmd_init_db },
 496         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 497         { "log", cmd_log, RUN_SETUP },
 498         { "ls-files", cmd_ls_files, RUN_SETUP },
 499         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 500         { "ls-tree", cmd_ls_tree, RUN_SETUP },
 501         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
 502         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 503         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 504         { "merge-base", cmd_merge_base, RUN_SETUP },
 505         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 506         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 507         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 508         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 509         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 510         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 511         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 512         { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
 513         { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
 514         { "mktree", cmd_mktree, RUN_SETUP },
 515         { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP_GENTLY },
 516         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 517         { "name-rev", cmd_name_rev, RUN_SETUP },
 518         { "notes", cmd_notes, RUN_SETUP },
 519         { "pack-objects", cmd_pack_objects, RUN_SETUP },
 520         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 521         { "pack-refs", cmd_pack_refs, RUN_SETUP },
 522         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 523         { "pickaxe", cmd_blame, RUN_SETUP },
 524         { "prune", cmd_prune, RUN_SETUP },
 525         { "prune-packed", cmd_prune_packed, RUN_SETUP },
 526         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 527         { "push", cmd_push, RUN_SETUP },
 528         { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },
 529         { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 530         /*
 531          * NEEDSWORK: Until the rebase is independent and needs no redirection
 532          * to rebase shell script this is kept as is, then should be changed to
 533          * RUN_SETUP | NEED_WORK_TREE
 534          */
 535         { "rebase", cmd_rebase },
 536         { "rebase--interactive", cmd_rebase__interactive, RUN_SETUP | NEED_WORK_TREE },
 537         { "receive-pack", cmd_receive_pack },
 538         { "reflog", cmd_reflog, RUN_SETUP },
 539         { "remote", cmd_remote, RUN_SETUP },
 540         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 541         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 542         { "repack", cmd_repack, RUN_SETUP },
 543         { "replace", cmd_replace, RUN_SETUP },
 544         { "rerere", cmd_rerere, RUN_SETUP },
 545         { "reset", cmd_reset, RUN_SETUP },
 546         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 547         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 548         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 549         { "rm", cmd_rm, RUN_SETUP },
 550         { "send-pack", cmd_send_pack, RUN_SETUP },
 551         { "serve", cmd_serve, RUN_SETUP },
 552         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 553         { "show", cmd_show, RUN_SETUP },
 554         { "show-branch", cmd_show_branch, RUN_SETUP },
 555         { "show-index", cmd_show_index },
 556         { "show-ref", cmd_show_ref, RUN_SETUP },
 557         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 558         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 559         { "stripspace", cmd_stripspace },
 560         { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
 561         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 562         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 563         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 564         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 565         { "update-index", cmd_update_index, RUN_SETUP },
 566         { "update-ref", cmd_update_ref, RUN_SETUP },
 567         { "update-server-info", cmd_update_server_info, RUN_SETUP },
 568         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 569         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 570         { "upload-pack", cmd_upload_pack },
 571         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 572         { "verify-commit", cmd_verify_commit, RUN_SETUP },
 573         { "verify-pack", cmd_verify_pack },
 574         { "verify-tag", cmd_verify_tag, RUN_SETUP },
 575         { "version", cmd_version },
 576         { "whatchanged", cmd_whatchanged, RUN_SETUP },
 577         { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
 578         { "write-tree", cmd_write_tree, RUN_SETUP },
 579 };
 580
 581 static struct cmd_struct *get_builtin(const char *s)
 582 {
 583         int i;
 584         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 585                 struct cmd_struct *p = commands + i;
 586                 if (!strcmp(s, p->cmd))
 587                         return p;
 588         }
 589         return NULL;
 590 }
 591
 592 int is_builtin(const char *s)
 593 {
 594         return !!get_builtin(s);
 595 }
 596
 597 static void list_builtins(struct string_list *out, unsigned int exclude_option)
 598 {
 599         int i;
 600         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 601                 if (exclude_option &&
 602                     (commands[i].option & exclude_option))
 603                         continue;
 604                 string_list_append(out, commands[i].cmd);
 605         }
 606 }
 607
 608 #ifdef STRIP_EXTENSION
 609 static void strip_extension(const char **argv)
 610 {
 611         size_t len;
 612
 613         if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 614                 argv[0] = xmemdupz(argv[0], len);
 615 }
 616 #else
 617 #define strip_extension(cmd)
 618 #endif
 619
 620 static void handle_builtin(int argc, const char **argv)
 621 {
 622         struct argv_array args = ARGV_ARRAY_INIT;
 623         const char *cmd;
 624         struct cmd_struct *builtin;
 625
 626         strip_extension(argv);
 627         cmd = argv[0];
 628
 629         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 630         if (argc > 1 && !strcmp(argv[1], "--help")) {
 631                 int i;
 632
 633                 argv[1] = argv[0];
 634                 argv[0] = cmd = "help";
 635
 636                 for (i = 0; i < argc; i++) {
 637                         argv_array_push(&args, argv[i]);
 638                         if (!i)
 639                                 argv_array_push(&args, "--exclude-guides");
 640                 }
 641
 642                 argc++;
 643                 argv = args.argv;
 644         }
 645
 646         builtin = get_builtin(cmd);
 647         if (builtin)
 648                 exit(run_builtin(builtin, argc, argv));
 649         argv_array_clear(&args);
 650 }
 651
 652 static void execv_dashed_external(const char **argv)
 653 {
 654         struct child_process cmd = CHILD_PROCESS_INIT;
 655         int status;
 656
 657         if (get_super_prefix())
 658                 die(_("%s doesn't support --super-prefix"), argv[0]);
 659
 660         if (use_pager == -1 && !is_builtin(argv[0]))
 661                 use_pager = check_pager_config(argv[0]);
 662         commit_pager_choice();
 663
 664         argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 665         argv_array_pushv(&cmd.args, argv + 1);
 666         cmd.clean_on_exit = 1;
 667         cmd.wait_after_clean = 1;
 668         cmd.silent_exec_failure = 1;
 669
 670         trace_argv_printf(cmd.args.argv, "trace: exec:");
 671
 672         /*
 673          * If we fail because the command is not found, it is
 674          * OK to return. Otherwise, we just pass along the status code,
 675          * or our usual generic code if we were not even able to exec
 676          * the program.
 677          */
 678         status = run_command(&cmd);
 679         if (status >= 0)
 680                 exit(status);
 681         else if (errno != ENOENT)
 682                 exit(128);
 683 }
 684
 685 static int run_argv(int *argcp, const char ***argv)
 686 {
 687         int done_alias = 0;
 688         struct string_list cmd_list = STRING_LIST_INIT_NODUP;
 689         struct string_list_item *seen;
 690
 691         while (1) {
 692                 /*
 693                  * If we tried alias and futzed with our environment,
 694                  * it no longer is safe to invoke builtins directly in
 695                  * general.  We have to spawn them as dashed externals.
 696                  *
 697                  * NEEDSWORK: if we can figure out cases
 698                  * where it is safe to do, we can avoid spawning a new
 699                  * process.
 700                  */
 701                 if (!done_alias)
 702                         handle_builtin(*argcp, *argv);
 703
 704                 /* .. then try the external ones */
 705                 execv_dashed_external(*argv);
 706
 707                 seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);
 708                 if (seen) {
 709                         int i;
 710                         struct strbuf sb = STRBUF_INIT;
 711                         for (i = 0; i < cmd_list.nr; i++) {
 712                                 struct string_list_item *item = &cmd_list.items[i];
 713
 714                                 strbuf_addf(&sb, "\n  %s", item->string);
 715                                 if (item == seen)
 716                                         strbuf_addstr(&sb, " <==");
 717                                 else if (i == cmd_list.nr - 1)
 718                                         strbuf_addstr(&sb, " ==>");
 719                         }
 720                         die(_("alias loop detected: expansion of '%s' does"
 721                               " not terminate:%s"), cmd_list.items[0].string, sb.buf);
 722                 }
 723
 724                 string_list_append(&cmd_list, *argv[0]);
 725
 726                 /*
 727                  * It could be an alias -- this works around the insanity
 728                  * of overriding "git log" with "git show" by having
 729                  * alias.log = show
 730                  */
 731                 if (!handle_alias(argcp, argv))
 732                         break;
 733                 done_alias = 1;
 734         }
 735
 736         string_list_clear(&cmd_list, 0);
 737
 738         return done_alias;
 739 }
 740
 741 int cmd_main(int argc, const char **argv)
 742 {
 743         const char *cmd;
 744         int done_help = 0;
 745
 746         cmd = argv[0];
 747         if (!cmd)
 748                 cmd = "git-help";
 749         else {
 750                 const char *slash = find_last_dir_sep(cmd);
 751                 if (slash)
 752                         cmd = slash + 1;
 753         }
 754
 755         trace_command_performance(argv);
 756
 757         /*
 758          * "git-xxxx" is the same as "git xxxx", but we obviously:
 759          *
 760          *  - cannot take flags in between the "git" and the "xxxx".
 761          *  - cannot execute it externally (since it would just do
 762          *    the same thing over again)
 763          *
 764          * So we just directly call the builtin handler, and die if
 765          * that one cannot handle it.
 766          */
 767         if (skip_prefix(cmd, "git-", &cmd)) {
 768                 argv[0] = cmd;
 769                 handle_builtin(argc, argv);
 770                 die(_("cannot handle %s as a builtin"), cmd);
 771         }
 772
 773         /* Look for flags.. */
 774         argv++;
 775         argc--;
 776         handle_options(&argv, &argc, NULL);
 777         if (argc > 0) {
 778                 /* translate --help and --version into commands */
 779                 skip_prefix(argv[0], "--", &argv[0]);
 780         } else {
 781                 /* The user didn't specify a command; give them help */
 782                 commit_pager_choice();
 783                 printf(_("usage: %s\n\n"), git_usage_string);
 784                 list_common_cmds_help();
 785                 printf("\n%s\n", _(git_more_info_string));
 786                 exit(1);
 787         }
 788         cmd = argv[0];
 789
 790         /*
 791          * We use PATH to find git commands, but we prepend some higher
 792          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 793          * environment, and the $(gitexecdir) from the Makefile at build
 794          * time.
 795          */
 796         setup_path();
 797
 798         while (1) {
 799                 int was_alias = run_argv(&argc, &argv);
 800                 if (errno != ENOENT)
 801                         break;
 802                 if (was_alias) {
 803                         fprintf(stderr, _("expansion of alias '%s' failed; "
 804                                           "'%s' is not a git command\n"),
 805                                 cmd, argv[0]);
 806                         exit(1);
 807                 }
 808                 if (!done_help) {
 809                         cmd = argv[0] = help_unknown_cmd(cmd);
 810                         done_help = 1;
 811                 } else
 812                         break;
 813         }
 814
 815         fprintf(stderr, _("failed to run command '%s': %s\n"),
 816                 cmd, strerror(errno));
 817
 818         return 1;
 819 }