git.c

   1 #define USE_THE_REPOSITORY_VARIABLE
   2
   3 #include "builtin.h"
   4 #include "config.h"
   5 #include "environment.h"
   6 #include "exec-cmd.h"
   7 #include "gettext.h"
   8 #include "help.h"
   9 #include "object-file.h"
  10 #include "pager.h"
  11 #include "read-cache-ll.h"
  12 #include "run-command.h"
  13 #include "alias.h"
  14 #include "replace-object.h"
  15 #include "setup.h"
  16 #include "attr.h"
  17 #include "shallow.h"
  18 #include "trace.h"
  19 #include "trace2.h"
  20
  21 #define RUN_SETUP               (1<<0)
  22 #define RUN_SETUP_GENTLY        (1<<1)
  23 #define USE_PAGER               (1<<2)
  24 /*
  25  * require working tree to be present -- anything uses this needs
  26  * RUN_SETUP for reading from the configuration file.
  27  */
  28 #define NEED_WORK_TREE          (1<<3)
  29 #define DELAY_PAGER_CONFIG      (1<<4)
  30 #define NO_PARSEOPT             (1<<5) /* parse-options is not used */
  31
  32 struct cmd_struct {
  33         const char *cmd;
  34         int (*fn)(int, const char **, const char *, struct repository *);
  35         unsigned int option;
  36 };
  37
  38 const char git_usage_string[] =
  39         N_("git [-v | --version] [-h | --help] [-C <path>] [-c <name>=<value>]\n"
  40            "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  41            "           [-p | --paginate | -P | --no-pager] [--no-replace-objects] [--no-lazy-fetch]\n"
  42            "           [--no-optional-locks] [--no-advice] [--bare] [--git-dir=<path>]\n"
  43            "           [--work-tree=<path>] [--namespace=<name>] [--config-env=<name>=<envvar>]\n"
  44            "           <command> [<args>]");
  45
  46 const char git_more_info_string[] =
  47         N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  48            "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  49            "to read about a specific subcommand or concept.\n"
  50            "See 'git help git' for an overview of the system.");
  51
  52 static int use_pager = -1;
  53
  54 static void list_builtins(struct string_list *list, unsigned int exclude_option);
  55
  56 static void exclude_helpers_from_list(struct string_list *list)
  57 {
  58         size_t i = 0;
  59
  60         while (i < list->nr) {
  61                 if (strstr(list->items[i].string, "--"))
  62                         unsorted_string_list_delete_item(list, i, 0);
  63                 else
  64                         i++;
  65         }
  66 }
  67
  68 static int match_token(const char *spec, int len, const char *token)
  69 {
  70         int token_len = strlen(token);
  71
  72         return len == token_len && !strncmp(spec, token, token_len);
  73 }
  74
  75 static int list_cmds(const char *spec)
  76 {
  77         struct string_list list = STRING_LIST_INIT_DUP;
  78         int nongit;
  79
  80         /*
  81         * Set up the repository so we can pick up any repo-level config (like
  82         * completion.commands).
  83         */
  84         setup_git_directory_gently(&nongit);
  85
  86         while (*spec) {
  87                 const char *sep = strchrnul(spec, ',');
  88                 int len = sep - spec;
  89
  90                 if (match_token(spec, len, "builtins"))
  91                         list_builtins(&list, 0);
  92                 else if (match_token(spec, len, "main"))
  93                         list_all_main_cmds(&list);
  94                 else if (match_token(spec, len, "others"))
  95                         list_all_other_cmds(&list);
  96                 else if (match_token(spec, len, "nohelpers"))
  97                         exclude_helpers_from_list(&list);
  98                 else if (match_token(spec, len, "alias"))
  99                         list_aliases(&list);
 100                 else if (match_token(spec, len, "config"))
 101                         list_cmds_by_config(&list);
 102                 else if (len > 5 && !strncmp(spec, "list-", 5)) {
 103                         struct strbuf sb = STRBUF_INIT;
 104
 105                         strbuf_add(&sb, spec + 5, len - 5);
 106                         list_cmds_by_category(&list, sb.buf);
 107                         strbuf_release(&sb);
 108                 }
 109                 else
 110                         die(_("unsupported command listing type '%s'"), spec);
 111                 spec += len;
 112                 if (*spec == ',')
 113                         spec++;
 114         }
 115         for (size_t i = 0; i < list.nr; i++)
 116                 puts(list.items[i].string);
 117         string_list_clear(&list, 0);
 118         return 0;
 119 }
 120
 121 static void commit_pager_choice(void)
 122 {
 123         switch (use_pager) {
 124         case 0:
 125                 setenv("GIT_PAGER", "cat", 1);
 126                 break;
 127         case 1:
 128                 setup_pager(the_repository);
 129                 break;
 130         default:
 131                 break;
 132         }
 133 }
 134
 135 void setup_auto_pager(const char *cmd, int def)
 136 {
 137         if (use_pager != -1 || pager_in_use())
 138                 return;
 139         use_pager = check_pager_config(the_repository, cmd);
 140         if (use_pager == -1)
 141                 use_pager = def;
 142         commit_pager_choice();
 143 }
 144
 145 static void print_system_path(const char *path)
 146 {
 147         char *s_path = system_path(path);
 148         puts(s_path);
 149         free(s_path);
 150 }
 151
 152 static int handle_options(const char ***argv, int *argc, int *envchanged)
 153 {
 154         const char **orig_argv = *argv;
 155
 156         while (*argc > 0) {
 157                 const char *cmd = (*argv)[0];
 158                 if (cmd[0] != '-')
 159                         break;
 160
 161                 /*
 162                  * For legacy reasons, the "version" and "help"
 163                  * commands can be written with "--" prepended
 164                  * to make them look like flags.
 165                  */
 166                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "-h") ||
 167                     !strcmp(cmd, "--version") || !strcmp(cmd, "-v"))
 168                         break;
 169
 170                 /*
 171                  * Check remaining flags.
 172                  */
 173                 if (skip_prefix(cmd, "--exec-path", &cmd)) {
 174                         if (*cmd == '=')
 175                                 git_set_exec_path(cmd + 1);
 176                         else {
 177                                 puts(git_exec_path());
 178                                 trace2_cmd_name("_query_");
 179                                 exit(0);
 180                         }
 181                 } else if (!strcmp(cmd, "--html-path")) {
 182                         print_system_path(GIT_HTML_PATH);
 183                         trace2_cmd_name("_query_");
 184                         exit(0);
 185                 } else if (!strcmp(cmd, "--man-path")) {
 186                         print_system_path(GIT_MAN_PATH);
 187                         trace2_cmd_name("_query_");
 188                         exit(0);
 189                 } else if (!strcmp(cmd, "--info-path")) {
 190                         print_system_path(GIT_INFO_PATH);
 191                         trace2_cmd_name("_query_");
 192                         exit(0);
 193                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 194                         use_pager = 1;
 195                 } else if (!strcmp(cmd, "-P") || !strcmp(cmd, "--no-pager")) {
 196                         use_pager = 0;
 197                         if (envchanged)
 198                                 *envchanged = 1;
 199                 } else if (!strcmp(cmd, "--no-lazy-fetch")) {
 200                         fetch_if_missing = 0;
 201                         setenv(NO_LAZY_FETCH_ENVIRONMENT, "1", 1);
 202                         if (envchanged)
 203                                 *envchanged = 1;
 204                 } else if (!strcmp(cmd, "--no-replace-objects")) {
 205                         disable_replace_refs();
 206                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 207                         if (envchanged)
 208                                 *envchanged = 1;
 209                 } else if (!strcmp(cmd, "--git-dir")) {
 210                         if (*argc < 2) {
 211                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "--git-dir");
 212                                 usage(git_usage_string);
 213                         }
 214                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 215                         if (envchanged)
 216                                 *envchanged = 1;
 217                         (*argv)++;
 218                         (*argc)--;
 219                 } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 220                         setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 221                         if (envchanged)
 222                                 *envchanged = 1;
 223                 } else if (!strcmp(cmd, "--namespace")) {
 224                         if (*argc < 2) {
 225                                 fprintf(stderr, _("no namespace given for --namespace\n" ));
 226                                 usage(git_usage_string);
 227                         }
 228                         setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 229                         if (envchanged)
 230                                 *envchanged = 1;
 231                         (*argv)++;
 232                         (*argc)--;
 233                 } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 234                         setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 235                         if (envchanged)
 236                                 *envchanged = 1;
 237                 } else if (!strcmp(cmd, "--work-tree")) {
 238                         if (*argc < 2) {
 239                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "--work-tree");
 240                                 usage(git_usage_string);
 241                         }
 242                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 243                         if (envchanged)
 244                                 *envchanged = 1;
 245                         (*argv)++;
 246                         (*argc)--;
 247                 } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 248                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 249                         if (envchanged)
 250                                 *envchanged = 1;
 251                 } else if (!strcmp(cmd, "--bare")) {
 252                         char *cwd = xgetcwd();
 253                         is_bare_repository_cfg = 1;
 254                         setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 255                         free(cwd);
 256                         setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 257                         if (envchanged)
 258                                 *envchanged = 1;
 259                 } else if (!strcmp(cmd, "-c")) {
 260                         if (*argc < 2) {
 261                                 fprintf(stderr, _("-c expects a configuration string\n" ));
 262                                 usage(git_usage_string);
 263                         }
 264                         git_config_push_parameter((*argv)[1]);
 265                         (*argv)++;
 266                         (*argc)--;
 267                 } else if (!strcmp(cmd, "--config-env")) {
 268                         if (*argc < 2) {
 269                                 fprintf(stderr, _("no config key given for --config-env\n" ));
 270                                 usage(git_usage_string);
 271                         }
 272                         git_config_push_env((*argv)[1]);
 273                         (*argv)++;
 274                         (*argc)--;
 275                 } else if (skip_prefix(cmd, "--config-env=", &cmd)) {
 276                         git_config_push_env(cmd);
 277                 } else if (!strcmp(cmd, "--literal-pathspecs")) {
 278                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 279                         if (envchanged)
 280                                 *envchanged = 1;
 281                 } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 282                         setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 283                         if (envchanged)
 284                                 *envchanged = 1;
 285                 } else if (!strcmp(cmd, "--glob-pathspecs")) {
 286                         setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 287                         if (envchanged)
 288                                 *envchanged = 1;
 289                 } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 290                         setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 291                         if (envchanged)
 292                                 *envchanged = 1;
 293                 } else if (!strcmp(cmd, "--icase-pathspecs")) {
 294                         setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 295                         if (envchanged)
 296                                 *envchanged = 1;
 297                 } else if (!strcmp(cmd, "--no-optional-locks")) {
 298                         setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 299                         if (envchanged)
 300                                 *envchanged = 1;
 301                 } else if (!strcmp(cmd, "--shallow-file")) {
 302                         (*argv)++;
 303                         (*argc)--;
 304                         set_alternate_shallow_file(the_repository, (*argv)[0], 1);
 305                         if (envchanged)
 306                                 *envchanged = 1;
 307                 } else if (!strcmp(cmd, "-C")) {
 308                         if (*argc < 2) {
 309                                 fprintf(stderr, _("no directory given for '%s' option\n" ), "-C");
 310                                 usage(git_usage_string);
 311                         }
 312                         if ((*argv)[1][0]) {
 313                                 if (chdir((*argv)[1]))
 314                                         die_errno("cannot change to '%s'", (*argv)[1]);
 315                                 if (envchanged)
 316                                         *envchanged = 1;
 317                         }
 318                         (*argv)++;
 319                         (*argc)--;
 320                 } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 321                         trace2_cmd_name("_query_");
 322                         if (!strcmp(cmd, "parseopt")) {
 323                                 struct string_list list = STRING_LIST_INIT_DUP;
 324
 325                                 list_builtins(&list, NO_PARSEOPT);
 326                                 for (size_t i = 0; i < list.nr; i++)
 327                                         printf("%s ", list.items[i].string);
 328                                 string_list_clear(&list, 0);
 329                                 exit(0);
 330                         } else {
 331                                 exit(list_cmds(cmd));
 332                         }
 333                 } else if (!strcmp(cmd, "--attr-source")) {
 334                         if (*argc < 2) {
 335                                 fprintf(stderr, _("no attribute source given for --attr-source\n" ));
 336                                 usage(git_usage_string);
 337                         }
 338                         setenv(GIT_ATTR_SOURCE_ENVIRONMENT, (*argv)[1], 1);
 339                         if (envchanged)
 340                                 *envchanged = 1;
 341                         (*argv)++;
 342                         (*argc)--;
 343                 } else if (skip_prefix(cmd, "--attr-source=", &cmd)) {
 344                         set_git_attr_source(cmd);
 345                         setenv(GIT_ATTR_SOURCE_ENVIRONMENT, cmd, 1);
 346                         if (envchanged)
 347                                 *envchanged = 1;
 348                 } else if (!strcmp(cmd, "--no-advice")) {
 349                         setenv(GIT_ADVICE_ENVIRONMENT, "0", 1);
 350                         if (envchanged)
 351                                 *envchanged = 1;
 352                 } else {
 353                         fprintf(stderr, _("unknown option: %s\n"), cmd);
 354                         usage(git_usage_string);
 355                 }
 356
 357                 (*argv)++;
 358                 (*argc)--;
 359         }
 360         return (*argv) - orig_argv;
 361 }
 362
 363 static int handle_alias(struct strvec *args)
 364 {
 365         int envchanged = 0, ret = 0, saved_errno = errno;
 366         int count, option_count;
 367         const char **new_argv;
 368         const char *alias_command;
 369         char *alias_string;
 370
 371         alias_command = args->v[0];
 372         alias_string = alias_lookup(alias_command);
 373         if (alias_string) {
 374                 if (args->nr > 1 && !strcmp(args->v[1], "-h"))
 375                         fprintf_ln(stderr, _("'%s' is aliased to '%s'"),
 376                                    alias_command, alias_string);
 377                 if (alias_string[0] == '!') {
 378                         struct child_process child = CHILD_PROCESS_INIT;
 379                         int nongit_ok;
 380
 381                         /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 382                         setup_git_directory_gently(&nongit_ok);
 383
 384                         commit_pager_choice();
 385
 386                         child.use_shell = 1;
 387                         child.clean_on_exit = 1;
 388                         child.wait_after_clean = 1;
 389                         child.trace2_child_class = "shell_alias";
 390                         strvec_push(&child.args, alias_string + 1);
 391                         strvec_pushv(&child.args, args->v + 1);
 392
 393                         trace2_cmd_alias(alias_command, child.args.v);
 394                         trace2_cmd_name("_run_shell_alias_");
 395
 396                         ret = run_command(&child);
 397                         if (ret >= 0)   /* normal exit */
 398                                 exit(ret);
 399
 400                         die_errno(_("while expanding alias '%s': '%s'"),
 401                                   alias_command, alias_string + 1);
 402                 }
 403                 count = split_cmdline(alias_string, &new_argv);
 404                 if (count < 0)
 405                         die(_("bad alias.%s string: %s"), alias_command,
 406                             _(split_cmdline_strerror(count)));
 407                 option_count = handle_options(&new_argv, &count, &envchanged);
 408                 if (envchanged)
 409                         die(_("alias '%s' changes environment variables.\n"
 410                               "You can use '!git' in the alias to do this"),
 411                             alias_command);
 412                 MOVE_ARRAY(new_argv - option_count, new_argv, count);
 413                 new_argv -= option_count;
 414
 415                 if (count < 1)
 416                         die(_("empty alias for %s"), alias_command);
 417
 418                 if (!strcmp(alias_command, new_argv[0]))
 419                         die(_("recursive alias: %s"), alias_command);
 420
 421                 trace_argv_printf(new_argv,
 422                                   "trace: alias expansion: %s =>",
 423                                   alias_command);
 424                 trace2_cmd_alias(alias_command, new_argv);
 425
 426                 /* Replace the alias with the new arguments. */
 427                 strvec_splice(args, 0, 1, new_argv, count);
 428
 429                 free(alias_string);
 430                 free(new_argv);
 431
 432                 ret = 1;
 433         }
 434
 435         errno = saved_errno;
 436
 437         return ret;
 438 }
 439
 440 static int run_builtin(struct cmd_struct *p, int argc, const char **argv, struct repository *repo)
 441 {
 442         int status, help;
 443         int no_repo = 1;
 444         struct stat st;
 445         const char *prefix;
 446         int run_setup = (p->option & (RUN_SETUP | RUN_SETUP_GENTLY));
 447
 448         help = argc == 2 && !strcmp(argv[1], "-h");
 449         if (help && (run_setup & RUN_SETUP))
 450                 /* demote to GENTLY to allow 'git cmd -h' outside repo */
 451                 run_setup = RUN_SETUP_GENTLY;
 452
 453         if (run_setup & RUN_SETUP) {
 454                 prefix = setup_git_directory();
 455                 no_repo = 0;
 456         } else if (run_setup & RUN_SETUP_GENTLY) {
 457                 prefix = setup_git_directory_gently(&no_repo);
 458         } else {
 459                 prefix = NULL;
 460         }
 461         assert(!prefix || *prefix);
 462         precompose_argv_prefix(argc, argv, NULL);
 463         if (use_pager == -1 && run_setup &&
 464                 !(p->option & DELAY_PAGER_CONFIG))
 465                 use_pager = check_pager_config(repo, p->cmd);
 466         if (use_pager == -1 && p->option & USE_PAGER)
 467                 use_pager = 1;
 468         if (run_setup && startup_info->have_repository)
 469                 /* get_git_dir() may set up repo, avoid that */
 470                 trace_repo_setup(repo);
 471         commit_pager_choice();
 472
 473         if (!help && p->option & NEED_WORK_TREE)
 474                 setup_work_tree();
 475
 476         trace_argv_printf(argv, "trace: built-in: git");
 477         trace2_cmd_name(p->cmd);
 478
 479         validate_cache_entries(repo->index);
 480         status = p->fn(argc, argv, prefix, no_repo ? NULL : repo);
 481         validate_cache_entries(repo->index);
 482
 483         if (status)
 484                 return status;
 485
 486         /* Somebody closed stdout? */
 487         if (fstat(fileno(stdout), &st))
 488                 return 0;
 489         /* Ignore write errors for pipes and sockets.. */
 490         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 491                 return 0;
 492
 493         /* Check for ENOSPC and EIO errors.. */
 494         if (fflush(stdout))
 495                 die_errno(_("write failure on standard output"));
 496         if (ferror(stdout))
 497                 die(_("unknown write failure on standard output"));
 498         if (fclose(stdout))
 499                 die_errno(_("close failed on standard output"));
 500         return 0;
 501 }
 502
 503 static struct cmd_struct commands[] = {
 504         { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 505         { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 506         { "annotate", cmd_annotate, RUN_SETUP },
 507         { "apply", cmd_apply, RUN_SETUP_GENTLY },
 508         { "archive", cmd_archive, RUN_SETUP_GENTLY },
 509         { "backfill", cmd_backfill, RUN_SETUP },
 510         { "bisect", cmd_bisect, RUN_SETUP },
 511         { "blame", cmd_blame, RUN_SETUP },
 512         { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 513         { "bugreport", cmd_bugreport, RUN_SETUP_GENTLY },
 514         { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 515         { "cat-file", cmd_cat_file, RUN_SETUP },
 516         { "check-attr", cmd_check_attr, RUN_SETUP },
 517         { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 518         { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 519         { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 520         { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 521         { "checkout--worker", cmd_checkout__worker,
 522                 RUN_SETUP | NEED_WORK_TREE },
 523         { "checkout-index", cmd_checkout_index,
 524                 RUN_SETUP | NEED_WORK_TREE},
 525         { "cherry", cmd_cherry, RUN_SETUP },
 526         { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 527         { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 528         { "clone", cmd_clone },
 529         { "column", cmd_column, RUN_SETUP_GENTLY },
 530         { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 531         { "commit-graph", cmd_commit_graph, RUN_SETUP },
 532         { "commit-tree", cmd_commit_tree, RUN_SETUP },
 533         { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 534         { "count-objects", cmd_count_objects, RUN_SETUP },
 535         { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 536         { "credential-cache", cmd_credential_cache },
 537         { "credential-cache--daemon", cmd_credential_cache_daemon },
 538         { "credential-store", cmd_credential_store },
 539         { "describe", cmd_describe, RUN_SETUP },
 540         { "diagnose", cmd_diagnose, RUN_SETUP_GENTLY },
 541         { "diff", cmd_diff, NO_PARSEOPT },
 542         { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 543         { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 544         { "diff-pairs", cmd_diff_pairs, RUN_SETUP | NO_PARSEOPT },
 545         { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 546         { "difftool", cmd_difftool, RUN_SETUP_GENTLY },
 547         { "fast-export", cmd_fast_export, RUN_SETUP },
 548         { "fast-import", cmd_fast_import, RUN_SETUP | NO_PARSEOPT },
 549         { "fetch", cmd_fetch, RUN_SETUP },
 550         { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 551         { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 552         { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 553         { "for-each-repo", cmd_for_each_repo, RUN_SETUP_GENTLY },
 554         { "format-patch", cmd_format_patch, RUN_SETUP },
 555         { "fsck", cmd_fsck, RUN_SETUP },
 556         { "fsck-objects", cmd_fsck, RUN_SETUP },
 557         { "fsmonitor--daemon", cmd_fsmonitor__daemon, RUN_SETUP },
 558         { "gc", cmd_gc, RUN_SETUP },
 559         { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 560         { "grep", cmd_grep, RUN_SETUP_GENTLY },
 561         { "hash-object", cmd_hash_object },
 562         { "help", cmd_help },
 563         { "hook", cmd_hook, RUN_SETUP },
 564         { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 565         { "init", cmd_init_db },
 566         { "init-db", cmd_init_db },
 567         { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 568         { "log", cmd_log, RUN_SETUP },
 569         { "ls-files", cmd_ls_files, RUN_SETUP },
 570         { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 571         { "ls-tree", cmd_ls_tree, RUN_SETUP },
 572         { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },
 573         { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 574         { "maintenance", cmd_maintenance, RUN_SETUP },
 575         { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 576         { "merge-base", cmd_merge_base, RUN_SETUP },
 577         { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 578         { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 579         { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 580         { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 581         { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 582         { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 583         { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 584         { "merge-tree", cmd_merge_tree, RUN_SETUP },
 585         { "mktag", cmd_mktag, RUN_SETUP },
 586         { "mktree", cmd_mktree, RUN_SETUP },
 587         { "multi-pack-index", cmd_multi_pack_index, RUN_SETUP },
 588         { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 589         { "name-rev", cmd_name_rev, RUN_SETUP },
 590         { "notes", cmd_notes, RUN_SETUP },
 591         { "pack-objects", cmd_pack_objects, RUN_SETUP },
 592 #ifndef WITH_BREAKING_CHANGES
 593         { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 594 #endif
 595         { "pack-refs", cmd_pack_refs, RUN_SETUP },
 596         { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 597         { "pickaxe", cmd_blame, RUN_SETUP },
 598         { "prune", cmd_prune, RUN_SETUP },
 599         { "prune-packed", cmd_prune_packed, RUN_SETUP },
 600         { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 601         { "push", cmd_push, RUN_SETUP },
 602         { "range-diff", cmd_range_diff, RUN_SETUP | USE_PAGER },
 603         { "read-tree", cmd_read_tree, RUN_SETUP },
 604         { "rebase", cmd_rebase, RUN_SETUP | NEED_WORK_TREE },
 605         { "receive-pack", cmd_receive_pack },
 606         { "reflog", cmd_reflog, RUN_SETUP },
 607         { "refs", cmd_refs, RUN_SETUP },
 608         { "remote", cmd_remote, RUN_SETUP },
 609         { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 610         { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 611         { "repack", cmd_repack, RUN_SETUP },
 612         { "replace", cmd_replace, RUN_SETUP },
 613         { "replay", cmd_replay, RUN_SETUP },
 614         { "rerere", cmd_rerere, RUN_SETUP },
 615         { "reset", cmd_reset, RUN_SETUP },
 616         { "restore", cmd_restore, RUN_SETUP | NEED_WORK_TREE },
 617         { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 618         { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 619         { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 620         { "rm", cmd_rm, RUN_SETUP },
 621         { "send-pack", cmd_send_pack, RUN_SETUP },
 622         { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 623         { "show", cmd_show, RUN_SETUP },
 624         { "show-branch", cmd_show_branch, RUN_SETUP },
 625         { "show-index", cmd_show_index, RUN_SETUP_GENTLY },
 626         { "show-ref", cmd_show_ref, RUN_SETUP },
 627         { "sparse-checkout", cmd_sparse_checkout, RUN_SETUP },
 628         { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 629         { "stash", cmd_stash, RUN_SETUP | NEED_WORK_TREE },
 630         { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 631         { "stripspace", cmd_stripspace },
 632         { "submodule--helper", cmd_submodule__helper, RUN_SETUP },
 633         { "switch", cmd_switch, RUN_SETUP | NEED_WORK_TREE },
 634         { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 635         { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 636         { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 637         { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 638         { "update-index", cmd_update_index, RUN_SETUP },
 639         { "update-ref", cmd_update_ref, RUN_SETUP },
 640         { "update-server-info", cmd_update_server_info, RUN_SETUP },
 641         { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 642         { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 643         { "upload-pack", cmd_upload_pack },
 644         { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 645         { "verify-commit", cmd_verify_commit, RUN_SETUP },
 646         { "verify-pack", cmd_verify_pack },
 647         { "verify-tag", cmd_verify_tag, RUN_SETUP },
 648         { "version", cmd_version },
 649 #ifndef WITH_BREAKING_CHANGES
 650         { "whatchanged", cmd_whatchanged, RUN_SETUP },
 651 #endif
 652         { "worktree", cmd_worktree, RUN_SETUP },
 653         { "write-tree", cmd_write_tree, RUN_SETUP },
 654 };
 655
 656 static struct cmd_struct *get_builtin(const char *s)
 657 {
 658         for (size_t i = 0; i < ARRAY_SIZE(commands); i++) {
 659                 struct cmd_struct *p = commands + i;
 660                 if (!strcmp(s, p->cmd))
 661                         return p;
 662         }
 663         return NULL;
 664 }
 665
 666 int is_builtin(const char *s)
 667 {
 668         return !!get_builtin(s);
 669 }
 670
 671 static void list_builtins(struct string_list *out, unsigned int exclude_option)
 672 {
 673         for (size_t i = 0; i < ARRAY_SIZE(commands); i++) {
 674                 if (exclude_option &&
 675                     (commands[i].option & exclude_option))
 676                         continue;
 677                 string_list_append(out, commands[i].cmd);
 678         }
 679 }
 680
 681 void load_builtin_commands(const char *prefix, struct cmdnames *cmds)
 682 {
 683         const char *name;
 684
 685         /*
 686          * Callers can ask for a subset of the commands based on a certain
 687          * prefix, which is then dropped from the added names. The names in
 688          * the `commands[]` array do not have the `git-` prefix, though,
 689          * therefore we must expect the `prefix` to at least start with `git-`.
 690          */
 691         if (!skip_prefix(prefix, "git-", &prefix))
 692                 BUG("prefix '%s' must start with 'git-'", prefix);
 693
 694         for (size_t i = 0; i < ARRAY_SIZE(commands); i++)
 695                 if (skip_prefix(commands[i].cmd, prefix, &name))
 696                         add_cmdname(cmds, name, strlen(name));
 697 }
 698
 699 #ifdef STRIP_EXTENSION
 700 static void strip_extension(struct strvec *args)
 701 {
 702         size_t len;
 703
 704         if (strip_suffix(args->v[0], STRIP_EXTENSION, &len)) {
 705                 char *stripped = xmemdupz(args->v[0], len);
 706                 strvec_replace(args, 0, stripped);
 707                 free(stripped);
 708         }
 709 }
 710 #else
 711 #define strip_extension(cmd)
 712 #endif
 713
 714 static void handle_builtin(struct strvec *args)
 715 {
 716         const char *cmd;
 717         struct cmd_struct *builtin;
 718
 719         strip_extension(args);
 720         cmd = args->v[0];
 721
 722         /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 723         if (args->nr > 1 && !strcmp(args->v[1], "--help")) {
 724                 const char *exclude_guides_arg[] = { "--exclude-guides" };
 725
 726                 strvec_replace(args, 1, args->v[0]);
 727                 strvec_replace(args, 0, "help");
 728                 cmd = "help";
 729                 strvec_splice(args, 2, 0, exclude_guides_arg,
 730                               ARRAY_SIZE(exclude_guides_arg));
 731         }
 732
 733         builtin = get_builtin(cmd);
 734         if (builtin) {
 735                 const char **argv_copy = NULL;
 736                 int ret;
 737
 738                 /*
 739                  * `run_builtin()` will modify the argv array, so we need to
 740                  * create a shallow copy such that we can free all of its
 741                  * strings.
 742                  */
 743                 if (args->nr)
 744                         DUP_ARRAY(argv_copy, args->v, args->nr + 1);
 745
 746                 ret = run_builtin(builtin, args->nr, argv_copy, the_repository);
 747                 strvec_clear(args);
 748                 free(argv_copy);
 749                 exit(ret);
 750         }
 751 }
 752
 753 static void execv_dashed_external(const char **argv)
 754 {
 755         struct child_process cmd = CHILD_PROCESS_INIT;
 756         int status;
 757
 758         if (use_pager == -1 && !is_builtin(argv[0]))
 759                 use_pager = check_pager_config(the_repository, argv[0]);
 760         commit_pager_choice();
 761
 762         strvec_pushf(&cmd.args, "git-%s", argv[0]);
 763         strvec_pushv(&cmd.args, argv + 1);
 764         cmd.clean_on_exit = 1;
 765         cmd.wait_after_clean = 1;
 766         cmd.silent_exec_failure = 1;
 767         cmd.trace2_child_class = "dashed";
 768
 769         trace2_cmd_name("_run_dashed_");
 770
 771         /*
 772          * The code in run_command() logs trace2 child_start/child_exit
 773          * events, so we do not need to report exec/exec_result events here.
 774          */
 775         trace_argv_printf(cmd.args.v, "trace: exec:");
 776
 777         /*
 778          * If we fail because the command is not found, it is
 779          * OK to return. Otherwise, we just pass along the status code,
 780          * or our usual generic code if we were not even able to exec
 781          * the program.
 782          */
 783         status = run_command(&cmd);
 784
 785         /*
 786          * If the child process ran and we are now going to exit, emit a
 787          * generic string as our trace2 command verb to indicate that we
 788          * launched a dashed command.
 789          */
 790         if (status >= 0)
 791                 exit(status);
 792         else if (errno != ENOENT)
 793                 exit(128);
 794 }
 795
 796 static int run_argv(struct strvec *args)
 797 {
 798         int done_alias = 0;
 799         struct string_list cmd_list = STRING_LIST_INIT_DUP;
 800         struct string_list_item *seen;
 801
 802         while (1) {
 803                 /*
 804                  * If we tried alias and futzed with our environment,
 805                  * it no longer is safe to invoke builtins directly in
 806                  * general.  We have to spawn them as dashed externals.
 807                  *
 808                  * NEEDSWORK: if we can figure out cases
 809                  * where it is safe to do, we can avoid spawning a new
 810                  * process.
 811                  */
 812                 if (!done_alias)
 813                         handle_builtin(args);
 814                 else if (get_builtin(args->v[0])) {
 815                         struct child_process cmd = CHILD_PROCESS_INIT;
 816                         int err;
 817
 818                         /*
 819                          * The current process is committed to launching a
 820                          * child process to run the command named in (**argv)
 821                          * and exiting.  Log a generic string as the trace2
 822                          * command verb to indicate this.  Note that the child
 823                          * process will log the actual verb when it runs.
 824                          */
 825                         trace2_cmd_name("_run_git_alias_");
 826
 827                         commit_pager_choice();
 828
 829                         strvec_push(&cmd.args, "git");
 830                         for (size_t i = 0; i < args->nr; i++)
 831                                 strvec_push(&cmd.args, args->v[i]);
 832
 833                         trace_argv_printf(cmd.args.v, "trace: exec:");
 834
 835                         /*
 836                          * if we fail because the command is not found, it is
 837                          * OK to return. Otherwise, we just pass along the status code.
 838                          */
 839                         cmd.silent_exec_failure = 1;
 840                         cmd.clean_on_exit = 1;
 841                         cmd.wait_after_clean = 1;
 842                         cmd.trace2_child_class = "git_alias";
 843                         err = run_command(&cmd);
 844                         if (err >= 0 || errno != ENOENT)
 845                                 exit(err);
 846                         die("could not execute builtin %s", args->v[0]);
 847                 }
 848
 849                 /* .. then try the external ones */
 850                 execv_dashed_external(args->v);
 851
 852                 seen = unsorted_string_list_lookup(&cmd_list, args->v[0]);
 853                 if (seen) {
 854                         struct strbuf sb = STRBUF_INIT;
 855                         for (size_t i = 0; i < cmd_list.nr; i++) {
 856                                 struct string_list_item *item = &cmd_list.items[i];
 857
 858                                 strbuf_addf(&sb, "\n  %s", item->string);
 859                                 if (item == seen)
 860                                         strbuf_addstr(&sb, " <==");
 861                                 else if (i == cmd_list.nr - 1)
 862                                         strbuf_addstr(&sb, " ==>");
 863                         }
 864                         die(_("alias loop detected: expansion of '%s' does"
 865                               " not terminate:%s"), cmd_list.items[0].string, sb.buf);
 866                 }
 867
 868                 string_list_append(&cmd_list, args->v[0]);
 869
 870                 /*
 871                  * It could be an alias -- this works around the insanity
 872                  * of overriding "git log" with "git show" by having
 873                  * alias.log = show
 874                  */
 875                 if (!handle_alias(args))
 876                         break;
 877                 done_alias = 1;
 878         }
 879
 880         string_list_clear(&cmd_list, 0);
 881
 882         return done_alias;
 883 }
 884
 885 int cmd_main(int argc, const char **argv)
 886 {
 887         struct strvec args = STRVEC_INIT;
 888         const char *cmd;
 889         int done_help = 0;
 890
 891         cmd = argv[0];
 892         if (!cmd)
 893                 cmd = "git-help";
 894         else {
 895                 const char *slash = find_last_dir_sep(cmd);
 896                 if (slash)
 897                         cmd = slash + 1;
 898         }
 899
 900         trace_command_performance(argv);
 901
 902         /*
 903          * "git-xxxx" is the same as "git xxxx", but we obviously:
 904          *
 905          *  - cannot take flags in between the "git" and the "xxxx".
 906          *  - cannot execute it externally (since it would just do
 907          *    the same thing over again)
 908          *
 909          * So we just directly call the builtin handler, and die if
 910          * that one cannot handle it.
 911          */
 912         if (skip_prefix(cmd, "git-", &cmd)) {
 913                 strvec_push(&args, cmd);
 914                 strvec_pushv(&args, argv + 1);
 915                 handle_builtin(&args);
 916                 strvec_clear(&args);
 917                 die(_("cannot handle %s as a builtin"), cmd);
 918         }
 919
 920         /* Look for flags.. */
 921         argv++;
 922         argc--;
 923         handle_options(&argv, &argc, NULL);
 924
 925         if (!argc) {
 926                 /* The user didn't specify a command; give them help */
 927                 commit_pager_choice();
 928                 printf(_("usage: %s\n\n"), git_usage_string);
 929                 list_common_cmds_help();
 930                 printf("\n%s\n", _(git_more_info_string));
 931                 exit(1);
 932         }
 933
 934         if (!strcmp("--version", argv[0]) || !strcmp("-v", argv[0]))
 935                 argv[0] = "version";
 936         else if (!strcmp("--help", argv[0]) || !strcmp("-h", argv[0]))
 937                 argv[0] = "help";
 938
 939         cmd = argv[0];
 940
 941         /*
 942          * We use PATH to find git commands, but we prepend some higher
 943          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 944          * environment, and the $(gitexecdir) from the Makefile at build
 945          * time.
 946          */
 947         setup_path();
 948
 949         for (int i = 0; i < argc; i++)
 950                 strvec_push(&args, argv[i]);
 951
 952         while (1) {
 953                 int was_alias = run_argv(&args);
 954                 if (errno != ENOENT)
 955                         break;
 956                 if (was_alias) {
 957                         fprintf(stderr, _("expansion of alias '%s' failed; "
 958                                           "'%s' is not a git command\n"),
 959                                 cmd, args.v[0]);
 960                         strvec_clear(&args);
 961                         exit(1);
 962                 }
 963                 if (!done_help) {
 964                         char *assumed = help_unknown_cmd(cmd);
 965                         strvec_replace(&args, 0, assumed);
 966                         free(assumed);
 967                         cmd = args.v[0];
 968                         done_help = 1;
 969                 } else {
 970                         break;
 971                 }
 972         }
 973
 974         fprintf(stderr, _("failed to run command '%s': %s\n"),
 975                 cmd, strerror(errno));
 976         strvec_clear(&args);
 977
 978         return 1;
 979 }