git.c

   1 #include "builtin.h"
   2 #include "config.h"
   3 #include "environment.h"
   4 #include "exec-cmd.h"
   5 #include "gettext.h"
   6 #include "help.h"
   7 #include "object-file.h"
   8 #include "pager.h"
   9 #include "read-cache-ll.h"
  10 #include "run-command.h"
  11 #include "alias.h"
  12 #include "replace-object.h"
  13 #include "setup.h"
  14 #include "attr.h"
  15 #include "shallow.h"
  16 #include "trace.h"
  17 #include "trace2.h"
  18
  19 #define RUN_SETUP               (1<<0)
  20 #define RUN_SETUP_GENTLY        (1<<1)
  21 #define USE_PAGER               (1<<2)
  22 /*
  23  * require working tree to be present -- anything uses this needs
  24  * RUN_SETUP for reading from the configuration file.
  25  */
  26 #define NEED_WORK_TREE          (1<<3)
  27 #define DELAY_PAGER_CONFIG      (1<<4)
  28 #define NO_PARSEOPT             (1<<5) /* parse-options is not used */
  29
  30 struct cmd_struct {
  31         const char *cmd;
  32         int (*fn)(int, const char **, const char *);
  33         unsigned int option;
  34 };
  35
  36 const char git_usage_string[] =
  37         N_("git [-v | --version] [-h | --help] [-C <path>] [-c <name>=<value>]\n"
  38            "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  39            "           [-p | --paginate | -P | --no-pager] [--no-replace-objects] [--no-lazy-fetch]\n"
  40            "           [--no-optional-locks] [--no-advice] [--bare] [--git-dir=<path>]\n"
  41            "           [--work-tree=<path>] [--namespace=<name>] [--config-env=<name>=<envvar>]\n"
  42            "           <command> [<args>]");
  43
  44 const char git_more_info_string[] =
  45         N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  46            "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  47            "to read about a specific subcommand or concept.\n"
  48            "See 'git help git' for an overview of the system.");
  49
  50 static int use_pager = -1;
  51
  52 static void list_builtins(struct string_list *list, unsigned int exclude_option);
  53
  54 static void exclude_helpers_from_list(struct string_list *list)
  55 {
  56         int i = 0;
  57
  58         while (i < list->nr) {
  59                 if (strstr(list->items[i].string, "--"))
  60                         unsorted_string_list_delete_item(list, i, 0);
  61                 else
  62                         i++;
  63         }
  64 }
  65
  66 static int match_token(const char *spec, int len, const char *token)
  67 {
  68         int token_len = strlen(token);
  69
  70         return len == token_len && !strncmp(spec, token, token_len);
  71 }
  72
  73 static int list_cmds(const char *spec)
  74 {
  75         struct string_list list = STRING_LIST_INIT_DUP;
  76         int i;
  77         int nongit;
  78
  79         /*
  80         * Set up the repository so we can pick up any repo-level config (like
  81         * completion.commands).
  82         */
  83         setup_git_directory_gently(&nongit);
  84
  85         while (*spec) {
  86                 const char *sep = strchrnul(spec, ',');
  87                 int len = sep - spec;
  88
  89                 if (match_token(spec, len, "builtins"))
  90                         list_builtins(&list, 0);
  91                 else if (match_token(spec, len, "main"))
  92                         list_all_main_cmds(&list);
  93                 else if (match_token(spec, len, "others"))
  94                         list_all_other_cmds(&list);
  95                 else if (match_token(spec, len, "nohelpers"))
  96                         exclude_helpers_from_list(&list);
  97                 else if (match_token(spec, len, "alias"))
  98                         list_aliases(&list);
  99                 else if (match_token(spec, len, "config"))
 100                         list_cmds_by_config(&list);
 101                 else if (len > 5 && !strncmp(spec, "list-", 5)) {
 102                         struct strbuf sb = STRBUF_INIT;
 103
 104                         strbuf_add(&sb, spec + 5, len - 5);
 105                         list_cmds_by_category(&list, sb.buf);
 106                         strbuf_release(&sb);
 107                 }
 108                 else
 109                         die(_("unsupported command listing type '%s'"), spec);
 110                 spec += len;
 111                 if (*spec == ',')
 112                         spec++;
 113         }
 114         for (i = 0; i < list.nr; i++)
 115                 puts(list.items[i].string);
 116         string_list_clear(&list, 0);
 117         return 0;
 118 }
 119
 120 static void commit_pager_choice(void)
 121 {
 122         switch (use_pager) {
 123         case 0:
 124                 setenv("GIT_PAGER", "cat", 1);
 125                 break;
 126         case 1:
 127                 setup_pager();
 128                 break;
 129         default:
 130                 break;
 131         }
 132 }
 133
 134 void setup_auto_pager(const char *cmd, int def)
 135 {
 136         if (use_pager != -1 || pager_in_use())
 137                 return;
 138         use_pager = check_pager_config(cmd);
 139         if (use_pager == -1)
 140                 use_pager = def;
 141         commit_pager_choice();
 142 }
 143
 144 static int handle_options(const char ***argv, int *argc, int *envchanged)
 145 {
 146         const char **orig_argv = *argv;
 147
 148         while (*argc > 0) {
 149                 const char *cmd = (*argv)[0];
 150                 if (cmd[0] != '-')
 151                         break;
 152
 153                 /*
 154                  * For legacy reasons, the "version" and "help"
 155                  * commands can be written with "--" prepended
 156                  * to make them look like flags.
 157                  */
 158                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h") ||
 159                     !strcmp(cmd, "--version") || !strcmp(cmd, "-v"))
 160                         break;
 161
 162                 /*
 163                  * Check remaining flags.
 164                  */
 165                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
 166                         if (*cmd == '=')
 167                                 git_set_exec_path(cmd + 1);
 168                         else {
 169                                 puts(git_exec_path());
 170                                 trace2_cmd_name("_query_");
 171                                 exit(0);
 172                         }
 173                 } else if (!strcmp(cmd, "--html-path")) {
 174                         puts(system_path(GIT_HTML_PATH));
 175                         trace2_cmd_name("_query_");
 176                         exit(0);
 177                 } else if (!strcmp(cmd, "--man-path")) {
 178                         puts(system_path(GIT_MAN_PATH));
 179                         trace2_cmd_name("_query_");
 180                         exit(0);
 181                 } else if (!strcmp(cmd, "--info-path")) {
 182                         puts(system_path(GIT_INFO_PATH));
 183                         trace2_cmd_name("_query_");
 184                         exit(0);
 185                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 186                         use_pager = 1;
 187                 } else if (!strcmp(cmd, "-P") || !strcmp(cmd, "--no-pager")) {
 188                         use_pager = 0;
 189                         if (envchanged)
 190                                 *envchanged = 1;
 191                 } else if (!strcmp(cmd, "--no-lazy-fetch")) {
 192                         fetch_if_missing = 0;
 193                         setenv(NO_LAZY_FETCH_ENVIRONMENT, "1", 1);
 194                         if (envchanged)
 195                                 *envchanged = 1;
 196                 } else if (!strcmp(cmd, "--no-replace-objects")) {
 197                         disable_replace_refs();
 198                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 199                         if (envchanged)
 200                                 *envchanged = 1;
 201                 } else if (!strcmp(cmd, "--git-dir")) {
 202                         if (*argc < 2) {
 203                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "--git-dir");
 204                                 usage(git_usage_string);
 205                         }
 206                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 207                         if (envchanged)
 208                                 *envchanged = 1;
 209                         (*argv)++;
 210                         (*argc)--;
 211                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 212                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 213                         if (envchanged)
 214                                 *envchanged = 1;
 215                 } else if (!strcmp(cmd, "--namespace")) {
 216                         if (*argc < 2) {
 217                                 fprintf(stderr, _("no namespace given for --namespace\n" ));
 218                                 usage(git_usage_string);
 219                         }
 220                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 221                         if (envchanged)
 222                                 *envchanged = 1;
 223                         (*argv)++;
 224                         (*argc)--;
 225                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 226                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 227                         if (envchanged)
 228                                 *envchanged = 1;
 229                 } else if (!strcmp(cmd, "--work-tree")) {
 230                         if (*argc < 2) {
 231                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "--work-tree");
 232                                 usage(git_usage_string);
 233                         }
 234                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 235                         if (envchanged)
 236                                 *envchanged = 1;
 237                         (*argv)++;
 238                         (*argc)--;
 239                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 240                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 241                         if (envchanged)
 242                                 *envchanged = 1;
 243                 } else if (!strcmp(cmd, "--bare")) {
 244                         char *cwd = xgetcwd();
 245                         is_bare_repository_cfg = 1;
 246                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 247                         free(cwd);
 248                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 249                         if (envchanged)
 250                                 *envchanged = 1;
 251                 } else if (!strcmp(cmd, "-c")) {
 252                         if (*argc < 2) {
 253                                 fprintf(stderr, _("-c expects a configuration string\n" ));
 254                                 usage(git_usage_string);
 255                         }
 256                         git_config_push_parameter((*argv)[1]);
 257                         (*argv)++;
 258                         (*argc)--;
 259                 } else if (!strcmp(cmd, "--config-env")) {
 260                         if (*argc < 2) {
 261                                 fprintf(stderr, _("no config key given for --config-env\n" ));
 262                                 usage(git_usage_string);
 263                         }
 264                         git_config_push_env((*argv)[1]);
 265                         (*argv)++;
 266                         (*argc)--;
 267                 } else if (skip_prefix(cmd, "--config-env=", &cmd)) {
 268                         git_config_push_env(cmd);
 269                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
 270                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 271                         if (envchanged)
 272                                 *envchanged = 1;
 273                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 274                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 275                         if (envchanged)
 276                                 *envchanged = 1;
 277                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
 278                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 279                         if (envchanged)
 280                                 *envchanged = 1;
 281                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 282                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 283                         if (envchanged)
 284                                 *envchanged = 1;
 285                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
 286                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 287                         if (envchanged)
 288                                 *envchanged = 1;
 289                 } else if (!strcmp(cmd, "--no-optional-locks")) {
 290                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 291                         if (envchanged)
 292                                 *envchanged = 1;
 293                 } else if (!strcmp(cmd, "--shallow-file")) {
 294                         (*argv)++;
 295                         (*argc)--;
 296                         set_alternate_shallow_file(the_repository, (*argv)[0], 1);
 297                         if (envchanged)
 298                                 *envchanged = 1;
 299                 } else if (!strcmp(cmd, "-C")) {
 300                         if (*argc < 2) {
 301                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "-C");
 302                                 usage(git_usage_string);
 303                         }
 304                         if ((*argv)[1][0]) {
 305                                 if (chdir((*argv)[1]))
 306                                         die_errno("cannot change to '%s'", (*argv)[1]);
 307                                 if (envchanged)
 308                                         *envchanged = 1;
 309                         }
 310                         (*argv)++;
 311                         (*argc)--;
 312                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 313                         trace2_cmd_name("_query_");
 314                         if (!strcmp(cmd, "parseopt")) {
 315                                 struct string_list list = STRING_LIST_INIT_DUP;
 316                                 int i;
 317
 318                                 list_builtins(&list, NO_PARSEOPT);
 319                                 for (i = 0; i < list.nr; i++)
 320                                         printf("%s ", list.items[i].string);
 321                                 string_list_clear(&list, 0);
 322                                 exit(0);
 323                         } else {
 324                                 exit(list_cmds(cmd));
 325                         }
 326                 } else if (!strcmp(cmd, "--attr-source")) {
 327                         if (*argc < 2) {
 328                                 fprintf(stderr, _("no attribute source given for --attr-source\n" ));
 329                                 usage(git_usage_string);
 330                         }
 331                         setenv(GIT_ATTR_SOURCE_ENVIRONMENT, (*argv)[1], 1);
 332                         if (envchanged)
 333                                 *envchanged = 1;
 334                         (*argv)++;
 335                         (*argc)--;
 336                 } else if (skip_prefix(cmd, "--attr-source=", &cmd)) {
 337                         set_git_attr_source(cmd);
 338                         setenv(GIT_ATTR_SOURCE_ENVIRONMENT, cmd, 1);
 339                         if (envchanged)
 340                                 *envchanged = 1;
 341                 } else if (!strcmp(cmd, "--no-advice")) {
 342                         setenv(GIT_ADVICE_ENVIRONMENT, "0", 1);
 343                         if (envchanged)
 344                                 *envchanged = 1;
 345                 } else {
 346                         fprintf(stderr, _("unknown option: %s\n"), cmd);
 347                         usage(git_usage_string);
 348                 }
 349
 350                 (*argv)++;
 351                 (*argc)--;
 352         }
 353         return (*argv) - orig_argv;
 354 }
 355
 356 static int handle_alias(int *argcp, const char ***argv)
 357 {
 358         int envchanged = 0, ret = 0, saved_errno = errno;
 359         int count, option_count;
 360         const char **new_argv;
 361         const char *alias_command;
 362         char *alias_string;
 363
 364         alias_command = (*argv)[0];
 365         alias_string = alias_lookup(alias_command);
 366         if (alias_string) {
 367                 if (*argcp > 1 && !strcmp((*argv)[1], "-h"))
 368                         fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
 369                                    alias_command, alias_string);
 370                 if (alias_string[0] == '!') {
 371                         struct child_process child = CHILD_PROCESS_INIT;
 372                         int nongit_ok;
 373
 374                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 375                         setup_git_directory_gently(&nongit_ok);
 376
 377                         commit_pager_choice();
 378
 379                         child.use_shell = 1;
 380                         child.clean_on_exit = 1;
 381                         child.wait_after_clean = 1;
 382                         child.trace2_child_class = "shell_alias";
 383                         strvec_push(&child.args, alias_string + 1);
 384                         strvec_pushv(&child.args, (*argv) + 1);
 385
 386                         trace2_cmd_alias(alias_command, child.args.v);
 387                         trace2_cmd_name("_run_shell_alias_");
 388
 389                         ret = run_command(&child);
 390                         if (ret >= 0)   /* normal exit */
 391                                 exit(ret);
 392
 393                         die_errno(_("while expanding alias '%s': '%s'"),
 394                                   alias_command, alias_string + 1);
 395                 }
 396                 count = split_cmdline(alias_string, &new_argv);
 397                 if (count < 0)
 398                         die(_("bad alias.%s string: %s"), alias_command,
 399                             _(split_cmdline_strerror(count)));
 400                 option_count = handle_options(&new_argv, &count, &envchanged);
 401                 if (envchanged)
 402                         die(_("alias '%s' changes environment variables.\n"
 403                               "You can use '!git' in the alias to do this"),
 404                             alias_command);
 405                 MOVE_ARRAY(new_argv - option_count, new_argv, count);
 406                 new_argv -= option_count;
 407
 408                 if (count < 1)
 409                         die(_("empty alias for %s"), alias_command);
 410
 411                 if (!strcmp(alias_command, new_argv[0]))
 412                         die(_("recursive alias: %s"), alias_command);
 413
 414                 trace_argv_printf(new_argv,
 415                                   "trace: alias expansion: %s =>",
 416                                   alias_command);
 417
 418                 REALLOC_ARRAY(new_argv, count + *argcp);
 419                 /* insert after command name */
 420                 COPY_ARRAY(new_argv + count, *argv + 1, *argcp);
 421
 422                 trace2_cmd_alias(alias_command, new_argv);
 423
 424                 *argv = new_argv;
 425                 *argcp += count - 1;
 426
 427                 ret = 1;
 428         }
 429
 430         errno = saved_errno;
 431
 432         return ret;
 433 }
 434
 435 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 436 {
 437         int status, help;
 438         struct stat st;
 439         const char *prefix;
 440         int run_setup = (p->option & (RUN_SETUP | RUN_SETUP_GENTLY));
 441
 442         help = argc == 2 && !strcmp(argv[1], "-h");
 443         if (help && (run_setup & RUN_SETUP))
 444                 /* demote to GENTLY to allow 'git cmd -h' outside repo */
 445                 run_setup = RUN_SETUP_GENTLY;
 446
 447         if (run_setup & RUN_SETUP) {
 448                 prefix = setup_git_directory();
 449         } else if (run_setup & RUN_SETUP_GENTLY) {
 450                 int nongit_ok;
 451                 prefix = setup_git_directory_gently(&nongit_ok);
 452         } else {
 453                 prefix = NULL;
 454         }
 455         assert(!prefix || *prefix);
 456         precompose_argv_prefix(argc, argv, NULL);
 457         if (use_pager == -1 && run_setup &&
 458                 !(p->option & DELAY_PAGER_CONFIG))
 459                 use_pager = check_pager_config(p->cmd);
 460         if (use_pager == -1 && p->option & USE_PAGER)
 461                 use_pager = 1;
 462         if (run_setup && startup_info->have_repository)
 463                 /* get_git_dir() may set up repo, avoid that */
 464                 trace_repo_setup();
 465         commit_pager_choice();
 466
 467         if (!help && p->option & NEED_WORK_TREE)
 468                 setup_work_tree();
 469
 470         trace_argv_printf(argv, "trace: built-in: git");
 471         trace2_cmd_name(p->cmd);
 472
 473         validate_cache_entries(the_repository->index);
 474         status = p->fn(argc, argv, prefix);
 475         validate_cache_entries(the_repository->index);
 476
 477         if (status)
 478                 return status;
 479
 480         /* Somebody closed stdout? */
 481         if (fstat(fileno(stdout), &st))
 482                 return 0;
 483         /* Ignore write errors for pipes and sockets.. */
 484         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 485                 return 0;
 486
 487         /* Check for ENOSPC and EIO errors.. */
 488         if (fflush(stdout))
 489                 die_errno(_("write failure on standard output"));
 490         if (ferror(stdout))
 491                 die(_("unknown write failure on standard output"));
 492         if (fclose(stdout))
 493                 die_errno(_("close failed on standard output"));
 494         return 0;
 495 }
 496
 497 static struct cmd_struct commands[] = {
 498         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 499         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 500         { "annotate", cmd_annotate, RUN_SETUP },
 501         { "apply", cmd_apply, RUN_SETUP_GENTLY },
 502         { "archive", cmd_archive, RUN_SETUP_GENTLY },
 503         { "bisect", cmd_bisect, RUN_SETUP },
 504         { "blame", cmd_blame, RUN_SETUP },
 505         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 506         { "bugreport", cmd_bugreport, RUN_SETUP_GENTLY },
 507         { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 508         { "cat-file", cmd_cat_file, RUN_SETUP },
 509         { "check-attr", cmd_check_attr, RUN_SETUP },
 510         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 511         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 512         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 513         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 514         { "checkout--worker", cmd_checkout__worker,
 515                 RUN_SETUP | NEED_WORK_TREE },
 516         { "checkout-index", cmd_checkout_index,
 517                 RUN_SETUP | NEED_WORK_TREE},
 518         { "cherry", cmd_cherry, RUN_SETUP },
 519         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 520         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 521         { "clone", cmd_clone },
 522         { "column", cmd_column, RUN_SETUP_GENTLY },
 523         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 524         { "commit-graph", cmd_commit_graph, RUN_SETUP },
 525         { "commit-tree", cmd_commit_tree, RUN_SETUP },
 526         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 527         { "count-objects", cmd_count_objects, RUN_SETUP },
 528         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 529         { "credential-cache", cmd_credential_cache },
 530         { "credential-cache--daemon", cmd_credential_cache_daemon },
 531         { "credential-store", cmd_credential_store },
 532         { "describe", cmd_describe, RUN_SETUP },
 533         { "diagnose", cmd_diagnose, RUN_SETUP_GENTLY },
 534         { "diff", cmd_diff, NO_PARSEOPT },
 535         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 536         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 537         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 538         { "difftool", cmd_difftool, RUN_SETUP_GENTLY },
 539         { "fast-export", cmd_fast_export, RUN_SETUP },
 540         { "fast-import", cmd_fast_import, RUN_SETUP | NO_PARSEOPT },
 541         { "fetch", cmd_fetch, RUN_SETUP },
 542         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 543         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 544         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 545         { "for-each-repo", cmd_for_each_repo, RUN_SETUP_GENTLY },
 546         { "format-patch", cmd_format_patch, RUN_SETUP },
 547         { "fsck", cmd_fsck, RUN_SETUP },
 548         { "fsck-objects", cmd_fsck, RUN_SETUP },
 549         { "fsmonitor--daemon", cmd_fsmonitor__daemon, RUN_SETUP },
 550         { "gc", cmd_gc, RUN_SETUP },
 551         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 552         { "grep", cmd_grep, RUN_SETUP_GENTLY },
 553         { "hash-object", cmd_hash_object },
 554         { "help", cmd_help },
 555         { "hook", cmd_hook, RUN_SETUP },
 556         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 557         { "init", cmd_init_db },
 558         { "init-db", cmd_init_db },
 559         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 560         { "log", cmd_log, RUN_SETUP },
 561         { "ls-files", cmd_ls_files, RUN_SETUP },
 562         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 563         { "ls-tree", cmd_ls_tree, RUN_SETUP },
 564         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },
 565         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 566         { "maintenance", cmd_maintenance, RUN_SETUP },
 567         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 568         { "merge-base", cmd_merge_base, RUN_SETUP },
 569         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 570         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 571         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 572         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 573         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 574         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 575         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 576         { "merge-tree", cmd_merge_tree, RUN_SETUP },
 577         { "mktag", cmd_mktag, RUN_SETUP },
 578         { "mktree", cmd_mktree, RUN_SETUP },
 579         { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP },
 580         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 581         { "name-rev", cmd_name_rev, RUN_SETUP },
 582         { "notes", cmd_notes, RUN_SETUP },
 583         { "pack-objects", cmd_pack_objects, RUN_SETUP },
 584         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 585         { "pack-refs", cmd_pack_refs, RUN_SETUP },
 586         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 587         { "pickaxe", cmd_blame, RUN_SETUP },
 588         { "prune", cmd_prune, RUN_SETUP },
 589         { "prune-packed", cmd_prune_packed, RUN_SETUP },
 590         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 591         { "push", cmd_push, RUN_SETUP },
 592         { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },
 593         { "read-tree", cmd_read_tree, RUN_SETUP },
 594         { "rebase", cmd_rebase, RUN_SETUP | NEED_WORK_TREE },
 595         { "receive-pack", cmd_receive_pack },
 596         { "reflog", cmd_reflog, RUN_SETUP },
 597         { "remote", cmd_remote, RUN_SETUP },
 598         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 599         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 600         { "repack", cmd_repack, RUN_SETUP },
 601         { "replace", cmd_replace, RUN_SETUP },
 602         { "replay", cmd_replay, RUN_SETUP },
 603         { "rerere", cmd_rerere, RUN_SETUP },
 604         { "reset", cmd_reset, RUN_SETUP },
 605         { "restore", cmd_restore, RUN_SETUP | NEED_WORK_TREE },
 606         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 607         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 608         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 609         { "rm", cmd_rm, RUN_SETUP },
 610         { "send-pack", cmd_send_pack, RUN_SETUP },
 611         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 612         { "show", cmd_show, RUN_SETUP },
 613         { "show-branch", cmd_show_branch, RUN_SETUP },
 614         { "show-index", cmd_show_index, RUN_SETUP_GENTLY },
 615         { "show-ref", cmd_show_ref, RUN_SETUP },
 616         { "sparse-checkout", cmd_sparse_checkout, RUN_SETUP },
 617         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 618         { "stash", cmd_stash, RUN_SETUP | NEED_WORK_TREE },
 619         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 620         { "stripspace", cmd_stripspace },
 621         { "submodule--helper", cmd_submodule__helper, RUN_SETUP },
 622         { "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },
 623         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 624         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 625         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 626         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 627         { "update-index", cmd_update_index, RUN_SETUP },
 628         { "update-ref", cmd_update_ref, RUN_SETUP },
 629         { "update-server-info", cmd_update_server_info, RUN_SETUP },
 630         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 631         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 632         { "upload-pack", cmd_upload_pack },
 633         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 634         { "verify-commit", cmd_verify_commit, RUN_SETUP },
 635         { "verify-pack", cmd_verify_pack },
 636         { "verify-tag", cmd_verify_tag, RUN_SETUP },
 637         { "version", cmd_version },
 638         { "whatchanged", cmd_whatchanged, RUN_SETUP },
 639         { "worktree", cmd_worktree, RUN_SETUP },
 640         { "write-tree", cmd_write_tree, RUN_SETUP },
 641 };
 642
 643 static struct cmd_struct *get_builtin(const char *s)
 644 {
 645         int i;
 646         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 647                 struct cmd_struct *p = commands + i;
 648                 if (!strcmp(s, p->cmd))
 649                         return p;
 650         }
 651         return NULL;
 652 }
 653
 654 int is_builtin(const char *s)
 655 {
 656         return !!get_builtin(s);
 657 }
 658
 659 static void list_builtins(struct string_list *out, unsigned int exclude_option)
 660 {
 661         int i;
 662         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 663                 if (exclude_option &&
 664                     (commands[i].option & exclude_option))
 665                         continue;
 666                 string_list_append(out, commands[i].cmd);
 667         }
 668 }
 669
 670 void load_builtin_commands(const char *prefix, struct cmdnames *cmds)
 671 {
 672         const char *name;
 673         int i;
 674
 675         /*
 676          * Callers can ask for a subset of the commands based on a certain
 677          * prefix, which is then dropped from the added names. The names in
 678          * the `commands[]` array do not have the `git-` prefix, though,
 679          * therefore we must expect the `prefix` to at least start with `git-`.
 680          */
 681         if (!skip_prefix(prefix, "git-", &prefix))
 682                 BUG("prefix '%s' must start with 'git-'", prefix);
 683
 684         for (i = 0; i < ARRAY_SIZE(commands); i++)
 685                 if (skip_prefix(commands[i].cmd, prefix, &name))
 686                         add_cmdname(cmds, name, strlen(name));
 687 }
 688
 689 #ifdef STRIP_EXTENSION
 690 static void strip_extension(const char **argv)
 691 {
 692         size_t len;
 693
 694         if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 695                 argv[0] = xmemdupz(argv[0], len);
 696 }
 697 #else
 698 #define strip_extension(cmd)
 699 #endif
 700
 701 static void handle_builtin(int argc, const char **argv)
 702 {
 703         struct strvec args = STRVEC_INIT;
 704         const char *cmd;
 705         struct cmd_struct *builtin;
 706
 707         strip_extension(argv);
 708         cmd = argv[0];
 709
 710         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 711         if (argc > 1 && !strcmp(argv[1], "--help")) {
 712                 int i;
 713
 714                 argv[1] = argv[0];
 715                 argv[0] = cmd = "help";
 716
 717                 for (i = 0; i < argc; i++) {
 718                         strvec_push(&args, argv[i]);
 719                         if (!i)
 720                                 strvec_push(&args, "--exclude-guides");
 721                 }
 722
 723                 argc++;
 724                 argv = args.v;
 725         }
 726
 727         builtin = get_builtin(cmd);
 728         if (builtin)
 729                 exit(run_builtin(builtin, argc, argv));
 730         strvec_clear(&args);
 731 }
 732
 733 static void execv_dashed_external(const char **argv)
 734 {
 735         struct child_process cmd = CHILD_PROCESS_INIT;
 736         int status;
 737
 738         if (use_pager == -1 && !is_builtin(argv[0]))
 739                 use_pager = check_pager_config(argv[0]);
 740         commit_pager_choice();
 741
 742         strvec_pushf(&cmd.args, "git-%s", argv[0]);
 743         strvec_pushv(&cmd.args, argv + 1);
 744         cmd.clean_on_exit = 1;
 745         cmd.wait_after_clean = 1;
 746         cmd.silent_exec_failure = 1;
 747         cmd.trace2_child_class = "dashed";
 748
 749         trace2_cmd_name("_run_dashed_");
 750
 751         /*
 752          * The code in run_command() logs trace2 child_start/child_exit
 753          * events, so we do not need to report exec/exec_result events here.
 754          */
 755         trace_argv_printf(cmd.args.v, "trace: exec:");
 756
 757         /*
 758          * If we fail because the command is not found, it is
 759          * OK to return. Otherwise, we just pass along the status code,
 760          * or our usual generic code if we were not even able to exec
 761          * the program.
 762          */
 763         status = run_command(&cmd);
 764
 765         /*
 766          * If the child process ran and we are now going to exit, emit a
 767          * generic string as our trace2 command verb to indicate that we
 768          * launched a dashed command.
 769          */
 770         if (status >= 0)
 771                 exit(status);
 772         else if (errno != ENOENT)
 773                 exit(128);
 774 }
 775
 776 static int run_argv(int *argcp, const char ***argv)
 777 {
 778         int done_alias = 0;
 779         struct string_list cmd_list = STRING_LIST_INIT_NODUP;
 780         struct string_list_item *seen;
 781
 782         while (1) {
 783                 /*
 784                  * If we tried alias and futzed with our environment,
 785                  * it no longer is safe to invoke builtins directly in
 786                  * general.  We have to spawn them as dashed externals.
 787                  *
 788                  * NEEDSWORK: if we can figure out cases
 789                  * where it is safe to do, we can avoid spawning a new
 790                  * process.
 791                  */
 792                 if (!done_alias)
 793                         handle_builtin(*argcp, *argv);
 794                 else if (get_builtin(**argv)) {
 795                         struct child_process cmd = CHILD_PROCESS_INIT;
 796                         int i;
 797
 798                         /*
 799                          * The current process is committed to launching a
 800                          * child process to run the command named in (**argv)
 801                          * and exiting.  Log a generic string as the trace2
 802                          * command verb to indicate this.  Note that the child
 803                          * process will log the actual verb when it runs.
 804                          */
 805                         trace2_cmd_name("_run_git_alias_");
 806
 807                         commit_pager_choice();
 808
 809                         strvec_push(&cmd.args, "git");
 810                         for (i = 0; i < *argcp; i++)
 811                                 strvec_push(&cmd.args, (*argv)[i]);
 812
 813                         trace_argv_printf(cmd.args.v, "trace: exec:");
 814
 815                         /*
 816                          * if we fail because the command is not found, it is
 817                          * OK to return. Otherwise, we just pass along the status code.
 818                          */
 819                         cmd.silent_exec_failure = 1;
 820                         cmd.clean_on_exit = 1;
 821                         cmd.wait_after_clean = 1;
 822                         cmd.trace2_child_class = "git_alias";
 823                         i = run_command(&cmd);
 824                         if (i >= 0 || errno != ENOENT)
 825                                 exit(i);
 826                         die("could not execute builtin %s", **argv);
 827                 }
 828
 829                 /* .. then try the external ones */
 830                 execv_dashed_external(*argv);
 831
 832                 seen = unsorted_string_list_lookup(&cmd_list, *argv[0]);
 833                 if (seen) {
 834                         int i;
 835                         struct strbuf sb = STRBUF_INIT;
 836                         for (i = 0; i < cmd_list.nr; i++) {
 837                                 struct string_list_item *item = &cmd_list.items[i];
 838
 839                                 strbuf_addf(&sb, "\n  %s", item->string);
 840                                 if (item == seen)
 841                                         strbuf_addstr(&sb, " <==");
 842                                 else if (i == cmd_list.nr - 1)
 843                                         strbuf_addstr(&sb, " ==>");
 844                         }
 845                         die(_("alias loop detected: expansion of '%s' does"
 846                               " not terminate:%s"), cmd_list.items[0].string, sb.buf);
 847                 }
 848
 849                 string_list_append(&cmd_list, *argv[0]);
 850
 851                 /*
 852                  * It could be an alias -- this works around the insanity
 853                  * of overriding "git log" with "git show" by having
 854                  * alias.log = show
 855                  */
 856                 if (!handle_alias(argcp, argv))
 857                         break;
 858                 done_alias = 1;
 859         }
 860
 861         string_list_clear(&cmd_list, 0);
 862
 863         return done_alias;
 864 }
 865
 866 int cmd_main(int argc, const char **argv)
 867 {
 868         const char *cmd;
 869         int done_help = 0;
 870
 871         cmd = argv[0];
 872         if (!cmd)
 873                 cmd = "git-help";
 874         else {
 875                 const char *slash = find_last_dir_sep(cmd);
 876                 if (slash)
 877                         cmd = slash + 1;
 878         }
 879
 880         trace_command_performance(argv);
 881
 882         /*
 883          * "git-xxxx" is the same as "git xxxx", but we obviously:
 884          *
 885          *  - cannot take flags in between the "git" and the "xxxx".
 886          *  - cannot execute it externally (since it would just do
 887          *    the same thing over again)
 888          *
 889          * So we just directly call the builtin handler, and die if
 890          * that one cannot handle it.
 891          */
 892         if (skip_prefix(cmd, "git-", &cmd)) {
 893                 argv[0] = cmd;
 894                 handle_builtin(argc, argv);
 895                 die(_("cannot handle %s as a builtin"), cmd);
 896         }
 897
 898         /* Look for flags.. */
 899         argv++;
 900         argc--;
 901         handle_options(&argv, &argc, NULL);
 902
 903         if (!argc) {
 904                 /* The user didn't specify a command; give them help */
 905                 commit_pager_choice();
 906                 printf(_("usage: %s\n\n"), git_usage_string);
 907                 list_common_cmds_help();
 908                 printf("\n%s\n", _(git_more_info_string));
 909                 exit(1);
 910         }
 911
 912         if (!strcmp("--version", argv[0]) || !strcmp("-v", argv[0]))
 913                 argv[0] = "version";
 914         else if (!strcmp("--help", argv[0]) || !strcmp("-h", argv[0]))
 915                 argv[0] = "help";
 916
 917         cmd = argv[0];
 918
 919         /*
 920          * We use PATH to find git commands, but we prepend some higher
 921          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 922          * environment, and the $(gitexecdir) from the Makefile at build
 923          * time.
 924          */
 925         setup_path();
 926
 927         while (1) {
 928                 int was_alias = run_argv(&argc, &argv);
 929                 if (errno != ENOENT)
 930                         break;
 931                 if (was_alias) {
 932                         fprintf(stderr, _("expansion of alias '%s' failed; "
 933                                           "'%s' is not a git command\n"),
 934                                 cmd, argv[0]);
 935                         exit(1);
 936                 }
 937                 if (!done_help) {
 938                         cmd = argv[0] = help_unknown_cmd(cmd);
 939                         done_help = 1;
 940                 } else
 941                         break;
 942         }
 943
 944         fprintf(stderr, _("failed to run command '%s': %s\n"),
 945                 cmd, strerror(errno));
 946
 947         return 1;
 948 }