Andrew's git / gitweb.git / git.c
?
git.con commit git --list-cmds: collect command list in a string_list (e5d7a61)
   1#include "builtin.h"
   2#include "config.h"
   3#include "exec_cmd.h"
   4#include "help.h"
   5#include "run-command.h"
   6
   7#define RUN_SETUP               (1<<0)
   8#define RUN_SETUP_GENTLY        (1<<1)
   9#define USE_PAGER               (1<<2)
  10/*
  11 * require working tree to be present -- anything uses this needs
  12 * RUN_SETUP for reading from the configuration file.
  13 */
  14#define NEED_WORK_TREE          (1<<3)
  15#define SUPPORT_SUPER_PREFIX    (1<<4)
  16#define DELAY_PAGER_CONFIG      (1<<5)
  17#define NO_PARSEOPT             (1<<6) /* parse-options is not used */
  18
  19struct cmd_struct {
  20        const char *cmd;
  21        int (*fn)(int, const char **, const char *);
  22        unsigned int option;
  23};
  24
  25const char git_usage_string[] =
  26        N_("git [--version] [--help] [-C <path>] [-c <name>=<value>]\n"
  27           "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  28           "           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
  29           "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  30           "           <command> [<args>]");
  31
  32const char git_more_info_string[] =
  33        N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  34           "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  35           "to read about a specific subcommand or concept.");
  36
  37static int use_pager = -1;
  38
  39static void list_builtins(struct string_list *list, unsigned int exclude_option);
  40
  41static int match_token(const char *spec, int len, const char *token)
  42{
  43        int token_len = strlen(token);
  44
  45        return len == token_len && !strncmp(spec, token, token_len);
  46}
  47
  48static int list_cmds(const char *spec)
  49{
  50        struct string_list list = STRING_LIST_INIT_DUP;
  51        int i;
  52
  53        while (*spec) {
  54                const char *sep = strchrnul(spec, ',');
  55                int len = sep - spec;
  56
  57                if (match_token(spec, len, "builtins"))
  58                        list_builtins(&list, 0);
  59                else
  60                        die(_("unsupported command listing type '%s'"), spec);
  61                spec += len;
  62                if (*spec == ',')
  63                        spec++;
  64        }
  65        for (i = 0; i < list.nr; i++)
  66                puts(list.items[i].string);
  67        string_list_clear(&list, 0);
  68        return 0;
  69}
  70
  71static void commit_pager_choice(void) {
  72        switch (use_pager) {
  73        case 0:
  74                setenv("GIT_PAGER", "cat", 1);
  75                break;
  76        case 1:
  77                setup_pager();
  78                break;
  79        default:
  80                break;
  81        }
  82}
  83
  84void setup_auto_pager(const char *cmd, int def)
  85{
  86        if (use_pager != -1 || pager_in_use())
  87                return;
  88        use_pager = check_pager_config(cmd);
  89        if (use_pager == -1)
  90                use_pager = def;
  91        commit_pager_choice();
  92}
  93
  94static int handle_options(const char ***argv, int *argc, int *envchanged)
  95{
  96        const char **orig_argv = *argv;
  97
  98        while (*argc > 0) {
  99                const char *cmd = (*argv)[0];
 100                if (cmd[0] != '-')
 101                        break;
 102
 103                /*
 104                 * For legacy reasons, the "version" and "help"
 105                 * commands can be written with "--" prepended
 106                 * to make them look like flags.
 107                 */
 108                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 109                        break;
 110
 111                /*
 112                 * Check remaining flags.
 113                 */
 114                if (skip_prefix(cmd, "--exec-path", &cmd)) {
 115                        if (*cmd == '=')
 116                                git_set_argv_exec_path(cmd + 1);
 117                        else {
 118                                puts(git_exec_path());
 119                                exit(0);
 120                        }
 121                } else if (!strcmp(cmd, "--html-path")) {
 122                        puts(system_path(GIT_HTML_PATH));
 123                        exit(0);
 124                } else if (!strcmp(cmd, "--man-path")) {
 125                        puts(system_path(GIT_MAN_PATH));
 126                        exit(0);
 127                } else if (!strcmp(cmd, "--info-path")) {
 128                        puts(system_path(GIT_INFO_PATH));
 129                        exit(0);
 130                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 131                        use_pager = 1;
 132                } else if (!strcmp(cmd, "--no-pager")) {
 133                        use_pager = 0;
 134                        if (envchanged)
 135                                *envchanged = 1;
 136                } else if (!strcmp(cmd, "--no-replace-objects")) {
 137                        check_replace_refs = 0;
 138                        setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 139                        if (envchanged)
 140                                *envchanged = 1;
 141                } else if (!strcmp(cmd, "--git-dir")) {
 142                        if (*argc < 2) {
 143                                fprintf(stderr, _("no directory given for --git-dir\n" ));
 144                                usage(git_usage_string);
 145                        }
 146                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 147                        if (envchanged)
 148                                *envchanged = 1;
 149                        (*argv)++;
 150                        (*argc)--;
 151                } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 152                        setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 153                        if (envchanged)
 154                                *envchanged = 1;
 155                } else if (!strcmp(cmd, "--namespace")) {
 156                        if (*argc < 2) {
 157                                fprintf(stderr, _("no namespace given for --namespace\n" ));
 158                                usage(git_usage_string);
 159                        }
 160                        setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 161                        if (envchanged)
 162                                *envchanged = 1;
 163                        (*argv)++;
 164                        (*argc)--;
 165                } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 166                        setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 167                        if (envchanged)
 168                                *envchanged = 1;
 169                } else if (!strcmp(cmd, "--work-tree")) {
 170                        if (*argc < 2) {
 171                                fprintf(stderr, _("no directory given for --work-tree\n" ));
 172                                usage(git_usage_string);
 173                        }
 174                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 175                        if (envchanged)
 176                                *envchanged = 1;
 177                        (*argv)++;
 178                        (*argc)--;
 179                } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 180                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 181                        if (envchanged)
 182                                *envchanged = 1;
 183                } else if (!strcmp(cmd, "--super-prefix")) {
 184                        if (*argc < 2) {
 185                                fprintf(stderr, _("no prefix given for --super-prefix\n" ));
 186                                usage(git_usage_string);
 187                        }
 188                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 189                        if (envchanged)
 190                                *envchanged = 1;
 191                        (*argv)++;
 192                        (*argc)--;
 193                } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 194                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 195                        if (envchanged)
 196                                *envchanged = 1;
 197                } else if (!strcmp(cmd, "--bare")) {
 198                        char *cwd = xgetcwd();
 199                        is_bare_repository_cfg = 1;
 200                        setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 201                        free(cwd);
 202                        setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 203                        if (envchanged)
 204                                *envchanged = 1;
 205                } else if (!strcmp(cmd, "-c")) {
 206                        if (*argc < 2) {
 207                                fprintf(stderr, _("-c expects a configuration string\n" ));
 208                                usage(git_usage_string);
 209                        }
 210                        git_config_push_parameter((*argv)[1]);
 211                        (*argv)++;
 212                        (*argc)--;
 213                } else if (!strcmp(cmd, "--literal-pathspecs")) {
 214                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 215                        if (envchanged)
 216                                *envchanged = 1;
 217                } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 218                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 219                        if (envchanged)
 220                                *envchanged = 1;
 221                } else if (!strcmp(cmd, "--glob-pathspecs")) {
 222                        setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 223                        if (envchanged)
 224                                *envchanged = 1;
 225                } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 226                        setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 227                        if (envchanged)
 228                                *envchanged = 1;
 229                } else if (!strcmp(cmd, "--icase-pathspecs")) {
 230                        setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 231                        if (envchanged)
 232                                *envchanged = 1;
 233                } else if (!strcmp(cmd, "--no-optional-locks")) {
 234                        setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 235                        if (envchanged)
 236                                *envchanged = 1;
 237                } else if (!strcmp(cmd, "--shallow-file")) {
 238                        (*argv)++;
 239                        (*argc)--;
 240                        set_alternate_shallow_file((*argv)[0], 1);
 241                        if (envchanged)
 242                                *envchanged = 1;
 243                } else if (!strcmp(cmd, "-C")) {
 244                        if (*argc < 2) {
 245                                fprintf(stderr, _("no directory given for -C\n" ));
 246                                usage(git_usage_string);
 247                        }
 248                        if ((*argv)[1][0]) {
 249                                if (chdir((*argv)[1]))
 250                                        die_errno("cannot change to '%s'", (*argv)[1]);
 251                                if (envchanged)
 252                                        *envchanged = 1;
 253                        }
 254                        (*argv)++;
 255                        (*argc)--;
 256                } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 257                        if (!strcmp(cmd, "parseopt")) {
 258                                struct string_list list = STRING_LIST_INIT_DUP;
 259                                int i;
 260
 261                                list_builtins(&list, NO_PARSEOPT);
 262                                for (i = 0; i < list.nr; i++)
 263                                        printf("%s ", list.items[i].string);
 264                                string_list_clear(&list, 0);
 265                                exit(0);
 266                        } else {
 267                                exit(list_cmds(cmd));
 268                        }
 269                } else {
 270                        fprintf(stderr, _("unknown option: %s\n"), cmd);
 271                        usage(git_usage_string);
 272                }
 273
 274                (*argv)++;
 275                (*argc)--;
 276        }
 277        return (*argv) - orig_argv;
 278}
 279
 280static int handle_alias(int *argcp, const char ***argv)
 281{
 282        int envchanged = 0, ret = 0, saved_errno = errno;
 283        int count, option_count;
 284        const char **new_argv;
 285        const char *alias_command;
 286        char *alias_string;
 287
 288        alias_command = (*argv)[0];
 289        alias_string = alias_lookup(alias_command);
 290        if (alias_string) {
 291                if (alias_string[0] == '!') {
 292                        struct child_process child = CHILD_PROCESS_INIT;
 293                        int nongit_ok;
 294
 295                        /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 296                        setup_git_directory_gently(&nongit_ok);
 297
 298                        commit_pager_choice();
 299
 300                        child.use_shell = 1;
 301                        argv_array_push(&child.args, alias_string + 1);
 302                        argv_array_pushv(&child.args, (*argv) + 1);
 303
 304                        ret = run_command(&child);
 305                        if (ret >= 0)   /* normal exit */
 306                                exit(ret);
 307
 308                        die_errno("while expanding alias '%s': '%s'",
 309                            alias_command, alias_string + 1);
 310                }
 311                count = split_cmdline(alias_string, &new_argv);
 312                if (count < 0)
 313                        die("Bad alias.%s string: %s", alias_command,
 314                            split_cmdline_strerror(count));
 315                option_count = handle_options(&new_argv, &count, &envchanged);
 316                if (envchanged)
 317                        die("alias '%s' changes environment variables.\n"
 318                                 "You can use '!git' in the alias to do this",
 319                                 alias_command);
 320                memmove(new_argv - option_count, new_argv,
 321                                count * sizeof(char *));
 322                new_argv -= option_count;
 323
 324                if (count < 1)
 325                        die("empty alias for %s", alias_command);
 326
 327                if (!strcmp(alias_command, new_argv[0]))
 328                        die("recursive alias: %s", alias_command);
 329
 330                trace_argv_printf(new_argv,
 331                                  "trace: alias expansion: %s =>",
 332                                  alias_command);
 333
 334                REALLOC_ARRAY(new_argv, count + *argcp);
 335                /* insert after command name */
 336                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 337
 338                *argv = new_argv;
 339                *argcp += count - 1;
 340
 341                ret = 1;
 342        }
 343
 344        errno = saved_errno;
 345
 346        return ret;
 347}
 348
 349static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 350{
 351        int status, help;
 352        struct stat st;
 353        const char *prefix;
 354
 355        prefix = NULL;
 356        help = argc == 2 && !strcmp(argv[1], "-h");
 357        if (!help) {
 358                if (p->option & RUN_SETUP)
 359                        prefix = setup_git_directory();
 360                else if (p->option & RUN_SETUP_GENTLY) {
 361                        int nongit_ok;
 362                        prefix = setup_git_directory_gently(&nongit_ok);
 363                }
 364
 365                if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
 366                    !(p->option & DELAY_PAGER_CONFIG))
 367                        use_pager = check_pager_config(p->cmd);
 368                if (use_pager == -1 && p->option & USE_PAGER)
 369                        use_pager = 1;
 370
 371                if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 372                    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 373                        trace_repo_setup(prefix);
 374        }
 375        commit_pager_choice();
 376
 377        if (!help && get_super_prefix()) {
 378                if (!(p->option & SUPPORT_SUPER_PREFIX))
 379                        die("%s doesn't support --super-prefix", p->cmd);
 380        }
 381
 382        if (!help && p->option & NEED_WORK_TREE)
 383                setup_work_tree();
 384
 385        trace_argv_printf(argv, "trace: built-in: git");
 386
 387        status = p->fn(argc, argv, prefix);
 388        if (status)
 389                return status;
 390
 391        /* Somebody closed stdout? */
 392        if (fstat(fileno(stdout), &st))
 393                return 0;
 394        /* Ignore write errors for pipes and sockets.. */
 395        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 396                return 0;
 397
 398        /* Check for ENOSPC and EIO errors.. */
 399        if (fflush(stdout))
 400                die_errno("write failure on standard output");
 401        if (ferror(stdout))
 402                die("unknown write failure on standard output");
 403        if (fclose(stdout))
 404                die_errno("close failed on standard output");
 405        return 0;
 406}
 407
 408static struct cmd_struct commands[] = {
 409        { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 410        { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 411        { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
 412        { "apply", cmd_apply, RUN_SETUP_GENTLY },
 413        { "archive", cmd_archive, RUN_SETUP_GENTLY },
 414        { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 415        { "blame", cmd_blame, RUN_SETUP },
 416        { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 417        { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
 418        { "cat-file", cmd_cat_file, RUN_SETUP },
 419        { "check-attr", cmd_check_attr, RUN_SETUP },
 420        { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 421        { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 422        { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 423        { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 424        { "checkout-index", cmd_checkout_index,
 425                RUN_SETUP | NEED_WORK_TREE},
 426        { "cherry", cmd_cherry, RUN_SETUP },
 427        { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 428        { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 429        { "clone", cmd_clone },
 430        { "column", cmd_column, RUN_SETUP_GENTLY },
 431        { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 432        { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
 433        { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 434        { "count-objects", cmd_count_objects, RUN_SETUP },
 435        { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 436        { "describe", cmd_describe, RUN_SETUP },
 437        { "diff", cmd_diff, NO_PARSEOPT },
 438        { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 439        { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 440        { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 441        { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 442        { "fast-export", cmd_fast_export, RUN_SETUP },
 443        { "fetch", cmd_fetch, RUN_SETUP },
 444        { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 445        { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 446        { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 447        { "format-patch", cmd_format_patch, RUN_SETUP },
 448        { "fsck", cmd_fsck, RUN_SETUP },
 449        { "fsck-objects", cmd_fsck, RUN_SETUP },
 450        { "gc", cmd_gc, RUN_SETUP },
 451        { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 452        { "grep", cmd_grep, RUN_SETUP_GENTLY },
 453        { "hash-object", cmd_hash_object },
 454        { "help", cmd_help },
 455        { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 456        { "init", cmd_init_db },
 457        { "init-db", cmd_init_db },
 458        { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 459        { "log", cmd_log, RUN_SETUP },
 460        { "ls-files", cmd_ls_files, RUN_SETUP },
 461        { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 462        { "ls-tree", cmd_ls_tree, RUN_SETUP },
 463        { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
 464        { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 465        { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 466        { "merge-base", cmd_merge_base, RUN_SETUP },
 467        { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 468        { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 469        { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 470        { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 471        { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 472        { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 473        { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 474        { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
 475        { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
 476        { "mktree", cmd_mktree, RUN_SETUP },
 477        { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 478        { "name-rev", cmd_name_rev, RUN_SETUP },
 479        { "notes", cmd_notes, RUN_SETUP },
 480        { "pack-objects", cmd_pack_objects, RUN_SETUP },
 481        { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 482        { "pack-refs", cmd_pack_refs, RUN_SETUP },
 483        { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 484        { "pickaxe", cmd_blame, RUN_SETUP },
 485        { "prune", cmd_prune, RUN_SETUP },
 486        { "prune-packed", cmd_prune_packed, RUN_SETUP },
 487        { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 488        { "push", cmd_push, RUN_SETUP },
 489        { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 490        { "rebase--helper", cmd_rebase__helper, RUN_SETUP | NEED_WORK_TREE },
 491        { "receive-pack", cmd_receive_pack },
 492        { "reflog", cmd_reflog, RUN_SETUP },
 493        { "remote", cmd_remote, RUN_SETUP },
 494        { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 495        { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 496        { "repack", cmd_repack, RUN_SETUP },
 497        { "replace", cmd_replace, RUN_SETUP },
 498        { "rerere", cmd_rerere, RUN_SETUP },
 499        { "reset", cmd_reset, RUN_SETUP },
 500        { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 501        { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 502        { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 503        { "rm", cmd_rm, RUN_SETUP },
 504        { "send-pack", cmd_send_pack, RUN_SETUP },
 505        { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 506        { "show", cmd_show, RUN_SETUP },
 507        { "show-branch", cmd_show_branch, RUN_SETUP },
 508        { "show-ref", cmd_show_ref, RUN_SETUP },
 509        { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 510        { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 511        { "stripspace", cmd_stripspace },
 512        { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
 513        { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 514        { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 515        { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 516        { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 517        { "update-index", cmd_update_index, RUN_SETUP },
 518        { "update-ref", cmd_update_ref, RUN_SETUP },
 519        { "update-server-info", cmd_update_server_info, RUN_SETUP },
 520        { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 521        { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 522        { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 523        { "verify-commit", cmd_verify_commit, RUN_SETUP },
 524        { "verify-pack", cmd_verify_pack },
 525        { "verify-tag", cmd_verify_tag, RUN_SETUP },
 526        { "version", cmd_version },
 527        { "whatchanged", cmd_whatchanged, RUN_SETUP },
 528        { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
 529        { "write-tree", cmd_write_tree, RUN_SETUP },
 530};
 531
 532static struct cmd_struct *get_builtin(const char *s)
 533{
 534        int i;
 535        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 536                struct cmd_struct *p = commands + i;
 537                if (!strcmp(s, p->cmd))
 538                        return p;
 539        }
 540        return NULL;
 541}
 542
 543int is_builtin(const char *s)
 544{
 545        return !!get_builtin(s);
 546}
 547
 548static void list_builtins(struct string_list *out, unsigned int exclude_option)
 549{
 550        int i;
 551        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 552                if (exclude_option &&
 553                    (commands[i].option & exclude_option))
 554                        continue;
 555                string_list_append(out, commands[i].cmd);
 556        }
 557}
 558
 559#ifdef STRIP_EXTENSION
 560static void strip_extension(const char **argv)
 561{
 562        size_t len;
 563
 564        if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 565                argv[0] = xmemdupz(argv[0], len);
 566}
 567#else
 568#define strip_extension(cmd)
 569#endif
 570
 571static void handle_builtin(int argc, const char **argv)
 572{
 573        struct argv_array args = ARGV_ARRAY_INIT;
 574        const char *cmd;
 575        struct cmd_struct *builtin;
 576
 577        strip_extension(argv);
 578        cmd = argv[0];
 579
 580        /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 581        if (argc > 1 && !strcmp(argv[1], "--help")) {
 582                int i;
 583
 584                argv[1] = argv[0];
 585                argv[0] = cmd = "help";
 586
 587                for (i = 0; i < argc; i++) {
 588                        argv_array_push(&args, argv[i]);
 589                        if (!i)
 590                                argv_array_push(&args, "--exclude-guides");
 591                }
 592
 593                argc++;
 594                argv = args.argv;
 595        }
 596
 597        builtin = get_builtin(cmd);
 598        if (builtin)
 599                exit(run_builtin(builtin, argc, argv));
 600        argv_array_clear(&args);
 601}
 602
 603static void execv_dashed_external(const char **argv)
 604{
 605        struct child_process cmd = CHILD_PROCESS_INIT;
 606        int status;
 607
 608        if (get_super_prefix())
 609                die("%s doesn't support --super-prefix", argv[0]);
 610
 611        if (use_pager == -1 && !is_builtin(argv[0]))
 612                use_pager = check_pager_config(argv[0]);
 613        commit_pager_choice();
 614
 615        argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 616        argv_array_pushv(&cmd.args, argv + 1);
 617        cmd.clean_on_exit = 1;
 618        cmd.wait_after_clean = 1;
 619        cmd.silent_exec_failure = 1;
 620
 621        trace_argv_printf(cmd.args.argv, "trace: exec:");
 622
 623        /*
 624         * If we fail because the command is not found, it is
 625         * OK to return. Otherwise, we just pass along the status code,
 626         * or our usual generic code if we were not even able to exec
 627         * the program.
 628         */
 629        status = run_command(&cmd);
 630        if (status >= 0)
 631                exit(status);
 632        else if (errno != ENOENT)
 633                exit(128);
 634}
 635
 636static int run_argv(int *argcp, const char ***argv)
 637{
 638        int done_alias = 0;
 639
 640        while (1) {
 641                /*
 642                 * If we tried alias and futzed with our environment,
 643                 * it no longer is safe to invoke builtins directly in
 644                 * general.  We have to spawn them as dashed externals.
 645                 *
 646                 * NEEDSWORK: if we can figure out cases
 647                 * where it is safe to do, we can avoid spawning a new
 648                 * process.
 649                 */
 650                if (!done_alias)
 651                        handle_builtin(*argcp, *argv);
 652
 653                /* .. then try the external ones */
 654                execv_dashed_external(*argv);
 655
 656                /* It could be an alias -- this works around the insanity
 657                 * of overriding "git log" with "git show" by having
 658                 * alias.log = show
 659                 */
 660                if (done_alias)
 661                        break;
 662                if (!handle_alias(argcp, argv))
 663                        break;
 664                done_alias = 1;
 665        }
 666
 667        return done_alias;
 668}
 669
 670int cmd_main(int argc, const char **argv)
 671{
 672        const char *cmd;
 673        int done_help = 0;
 674
 675        cmd = argv[0];
 676        if (!cmd)
 677                cmd = "git-help";
 678        else {
 679                const char *slash = find_last_dir_sep(cmd);
 680                if (slash)
 681                        cmd = slash + 1;
 682        }
 683
 684        trace_command_performance(argv);
 685
 686        /*
 687         * "git-xxxx" is the same as "git xxxx", but we obviously:
 688         *
 689         *  - cannot take flags in between the "git" and the "xxxx".
 690         *  - cannot execute it externally (since it would just do
 691         *    the same thing over again)
 692         *
 693         * So we just directly call the builtin handler, and die if
 694         * that one cannot handle it.
 695         */
 696        if (skip_prefix(cmd, "git-", &cmd)) {
 697                argv[0] = cmd;
 698                handle_builtin(argc, argv);
 699                die("cannot handle %s as a builtin", cmd);
 700        }
 701
 702        /* Look for flags.. */
 703        argv++;
 704        argc--;
 705        handle_options(&argv, &argc, NULL);
 706        if (argc > 0) {
 707                /* translate --help and --version into commands */
 708                skip_prefix(argv[0], "--", &argv[0]);
 709        } else {
 710                /* The user didn't specify a command; give them help */
 711                commit_pager_choice();
 712                printf("usage: %s\n\n", git_usage_string);
 713                list_common_cmds_help();
 714                printf("\n%s\n", _(git_more_info_string));
 715                exit(1);
 716        }
 717        cmd = argv[0];
 718
 719        /*
 720         * We use PATH to find git commands, but we prepend some higher
 721         * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 722         * environment, and the $(gitexecdir) from the Makefile at build
 723         * time.
 724         */
 725        setup_path();
 726
 727        while (1) {
 728                int was_alias = run_argv(&argc, &argv);
 729                if (errno != ENOENT)
 730                        break;
 731                if (was_alias) {
 732                        fprintf(stderr, _("expansion of alias '%s' failed; "
 733                                          "'%s' is not a git command\n"),
 734                                cmd, argv[0]);
 735                        exit(1);
 736                }
 737                if (!done_help) {
 738                        cmd = argv[0] = help_unknown_cmd(cmd);
 739                        done_help = 1;
 740                } else
 741                        break;
 742        }
 743
 744        fprintf(stderr, _("failed to run command '%s': %s\n"),
 745                cmd, strerror(errno));
 746
 747        return 1;
 748}