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