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