Andrew's git / gitweb.git / git.c
?
git.con commit Move declaration for alias.c to alias.h (65b5f94)
   1#include "builtin.h"
   2#include "config.h"
   3#include "exec_cmd.h"
   4#include "help.h"
   5#include "run-command.h"
   6#include "alias.h"
   7
   8#define RUN_SETUP               (1<<0)
   9#define RUN_SETUP_GENTLY        (1<<1)
  10#define USE_PAGER               (1<<2)
  11/*
  12 * require working tree to be present -- anything uses this needs
  13 * RUN_SETUP for reading from the configuration file.
  14 */
  15#define NEED_WORK_TREE          (1<<3)
  16#define SUPPORT_SUPER_PREFIX    (1<<4)
  17#define DELAY_PAGER_CONFIG      (1<<5)
  18#define NO_PARSEOPT             (1<<6) /* parse-options is not used */
  19
  20struct cmd_struct {
  21        const char *cmd;
  22        int (*fn)(int, const char **, const char *);
  23        unsigned int option;
  24};
  25
  26const char git_usage_string[] =
  27        N_("git [--version] [--help] [-C <path>] [-c <name>=<value>]\n"
  28           "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  29           "           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
  30           "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  31           "           <command> [<args>]");
  32
  33const char git_more_info_string[] =
  34        N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  35           "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  36           "to read about a specific subcommand or concept.");
  37
  38static int use_pager = -1;
  39
  40static void list_builtins(struct string_list *list, unsigned int exclude_option);
  41
  42static int match_token(const char *spec, int len, const char *token)
  43{
  44        int token_len = strlen(token);
  45
  46        return len == token_len && !strncmp(spec, token, token_len);
  47}
  48
  49static int list_cmds(const char *spec)
  50{
  51        struct string_list list = STRING_LIST_INIT_DUP;
  52        int i;
  53
  54        while (*spec) {
  55                const char *sep = strchrnul(spec, ',');
  56                int len = sep - spec;
  57
  58                if (match_token(spec, len, "builtins"))
  59                        list_builtins(&list, 0);
  60                else if (match_token(spec, len, "main"))
  61                        list_all_main_cmds(&list);
  62                else if (match_token(spec, len, "others"))
  63                        list_all_other_cmds(&list);
  64                else if (len > 5 && !strncmp(spec, "list-", 5)) {
  65                        struct strbuf sb = STRBUF_INIT;
  66
  67                        strbuf_add(&sb, spec + 5, len - 5);
  68                        list_cmds_by_category(&list, sb.buf);
  69                        strbuf_release(&sb);
  70                }
  71                else
  72                        die(_("unsupported command listing type '%s'"), spec);
  73                spec += len;
  74                if (*spec == ',')
  75                        spec++;
  76        }
  77        for (i = 0; i < list.nr; i++)
  78                puts(list.items[i].string);
  79        string_list_clear(&list, 0);
  80        return 0;
  81}
  82
  83static void commit_pager_choice(void) {
  84        switch (use_pager) {
  85        case 0:
  86                setenv("GIT_PAGER", "cat", 1);
  87                break;
  88        case 1:
  89                setup_pager();
  90                break;
  91        default:
  92                break;
  93        }
  94}
  95
  96void setup_auto_pager(const char *cmd, int def)
  97{
  98        if (use_pager != -1 || pager_in_use())
  99                return;
 100        use_pager = check_pager_config(cmd);
 101        if (use_pager == -1)
 102                use_pager = def;
 103        commit_pager_choice();
 104}
 105
 106static int handle_options(const char ***argv, int *argc, int *envchanged)
 107{
 108        const char **orig_argv = *argv;
 109
 110        while (*argc > 0) {
 111                const char *cmd = (*argv)[0];
 112                if (cmd[0] != '-')
 113                        break;
 114
 115                /*
 116                 * For legacy reasons, the "version" and "help"
 117                 * commands can be written with "--" prepended
 118                 * to make them look like flags.
 119                 */
 120                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
 121                        break;
 122
 123                /*
 124                 * Check remaining flags.
 125                 */
 126                if (skip_prefix(cmd, "--exec-path", &cmd)) {
 127                        if (*cmd == '=')
 128                                git_set_argv_exec_path(cmd + 1);
 129                        else {
 130                                puts(git_exec_path());
 131                                exit(0);
 132                        }
 133                } else if (!strcmp(cmd, "--html-path")) {
 134                        puts(system_path(GIT_HTML_PATH));
 135                        exit(0);
 136                } else if (!strcmp(cmd, "--man-path")) {
 137                        puts(system_path(GIT_MAN_PATH));
 138                        exit(0);
 139                } else if (!strcmp(cmd, "--info-path")) {
 140                        puts(system_path(GIT_INFO_PATH));
 141                        exit(0);
 142                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
 143                        use_pager = 1;
 144                } else if (!strcmp(cmd, "--no-pager")) {
 145                        use_pager = 0;
 146                        if (envchanged)
 147                                *envchanged = 1;
 148                } else if (!strcmp(cmd, "--no-replace-objects")) {
 149                        check_replace_refs = 0;
 150                        setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
 151                        if (envchanged)
 152                                *envchanged = 1;
 153                } else if (!strcmp(cmd, "--git-dir")) {
 154                        if (*argc < 2) {
 155                                fprintf(stderr, _("no directory given for --git-dir\n" ));
 156                                usage(git_usage_string);
 157                        }
 158                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 159                        if (envchanged)
 160                                *envchanged = 1;
 161                        (*argv)++;
 162                        (*argc)--;
 163                } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
 164                        setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
 165                        if (envchanged)
 166                                *envchanged = 1;
 167                } else if (!strcmp(cmd, "--namespace")) {
 168                        if (*argc < 2) {
 169                                fprintf(stderr, _("no namespace given for --namespace\n" ));
 170                                usage(git_usage_string);
 171                        }
 172                        setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 173                        if (envchanged)
 174                                *envchanged = 1;
 175                        (*argv)++;
 176                        (*argc)--;
 177                } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 178                        setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 179                        if (envchanged)
 180                                *envchanged = 1;
 181                } else if (!strcmp(cmd, "--work-tree")) {
 182                        if (*argc < 2) {
 183                                fprintf(stderr, _("no directory given for --work-tree\n" ));
 184                                usage(git_usage_string);
 185                        }
 186                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 187                        if (envchanged)
 188                                *envchanged = 1;
 189                        (*argv)++;
 190                        (*argc)--;
 191                } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 192                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 193                        if (envchanged)
 194                                *envchanged = 1;
 195                } else if (!strcmp(cmd, "--super-prefix")) {
 196                        if (*argc < 2) {
 197                                fprintf(stderr, _("no prefix given for --super-prefix\n" ));
 198                                usage(git_usage_string);
 199                        }
 200                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 201                        if (envchanged)
 202                                *envchanged = 1;
 203                        (*argv)++;
 204                        (*argc)--;
 205                } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 206                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 207                        if (envchanged)
 208                                *envchanged = 1;
 209                } else if (!strcmp(cmd, "--bare")) {
 210                        char *cwd = xgetcwd();
 211                        is_bare_repository_cfg = 1;
 212                        setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 213                        free(cwd);
 214                        setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 215                        if (envchanged)
 216                                *envchanged = 1;
 217                } else if (!strcmp(cmd, "-c")) {
 218                        if (*argc < 2) {
 219                                fprintf(stderr, _("-c expects a configuration string\n" ));
 220                                usage(git_usage_string);
 221                        }
 222                        git_config_push_parameter((*argv)[1]);
 223                        (*argv)++;
 224                        (*argc)--;
 225                } else if (!strcmp(cmd, "--literal-pathspecs")) {
 226                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 227                        if (envchanged)
 228                                *envchanged = 1;
 229                } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 230                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 231                        if (envchanged)
 232                                *envchanged = 1;
 233                } else if (!strcmp(cmd, "--glob-pathspecs")) {
 234                        setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 235                        if (envchanged)
 236                                *envchanged = 1;
 237                } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 238                        setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 239                        if (envchanged)
 240                                *envchanged = 1;
 241                } else if (!strcmp(cmd, "--icase-pathspecs")) {
 242                        setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 243                        if (envchanged)
 244                                *envchanged = 1;
 245                } else if (!strcmp(cmd, "--no-optional-locks")) {
 246                        setenv(GIT_OPTIONAL_LOCKS_ENVIRONMENT, "0", 1);
 247                        if (envchanged)
 248                                *envchanged = 1;
 249                } else if (!strcmp(cmd, "--shallow-file")) {
 250                        (*argv)++;
 251                        (*argc)--;
 252                        set_alternate_shallow_file((*argv)[0], 1);
 253                        if (envchanged)
 254                                *envchanged = 1;
 255                } else if (!strcmp(cmd, "-C")) {
 256                        if (*argc < 2) {
 257                                fprintf(stderr, _("no directory given for -C\n" ));
 258                                usage(git_usage_string);
 259                        }
 260                        if ((*argv)[1][0]) {
 261                                if (chdir((*argv)[1]))
 262                                        die_errno("cannot change to '%s'", (*argv)[1]);
 263                                if (envchanged)
 264                                        *envchanged = 1;
 265                        }
 266                        (*argv)++;
 267                        (*argc)--;
 268                } else if (skip_prefix(cmd, "--list-cmds=", &cmd)) {
 269                        if (!strcmp(cmd, "parseopt")) {
 270                                struct string_list list = STRING_LIST_INIT_DUP;
 271                                int i;
 272
 273                                list_builtins(&list, NO_PARSEOPT);
 274                                for (i = 0; i < list.nr; i++)
 275                                        printf("%s ", list.items[i].string);
 276                                string_list_clear(&list, 0);
 277                                exit(0);
 278                        } else {
 279                                exit(list_cmds(cmd));
 280                        }
 281                } else {
 282                        fprintf(stderr, _("unknown option: %s\n"), cmd);
 283                        usage(git_usage_string);
 284                }
 285
 286                (*argv)++;
 287                (*argc)--;
 288        }
 289        return (*argv) - orig_argv;
 290}
 291
 292static int handle_alias(int *argcp, const char ***argv)
 293{
 294        int envchanged = 0, ret = 0, saved_errno = errno;
 295        int count, option_count;
 296        const char **new_argv;
 297        const char *alias_command;
 298        char *alias_string;
 299
 300        alias_command = (*argv)[0];
 301        alias_string = alias_lookup(alias_command);
 302        if (alias_string) {
 303                if (alias_string[0] == '!') {
 304                        struct child_process child = CHILD_PROCESS_INIT;
 305                        int nongit_ok;
 306
 307                        /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 308                        setup_git_directory_gently(&nongit_ok);
 309
 310                        commit_pager_choice();
 311
 312                        child.use_shell = 1;
 313                        argv_array_push(&child.args, alias_string + 1);
 314                        argv_array_pushv(&child.args, (*argv) + 1);
 315
 316                        ret = run_command(&child);
 317                        if (ret >= 0)   /* normal exit */
 318                                exit(ret);
 319
 320                        die_errno("while expanding alias '%s': '%s'",
 321                            alias_command, alias_string + 1);
 322                }
 323                count = split_cmdline(alias_string, &new_argv);
 324                if (count < 0)
 325                        die("Bad alias.%s string: %s", alias_command,
 326                            split_cmdline_strerror(count));
 327                option_count = handle_options(&new_argv, &count, &envchanged);
 328                if (envchanged)
 329                        die("alias '%s' changes environment variables.\n"
 330                                 "You can use '!git' in the alias to do this",
 331                                 alias_command);
 332                memmove(new_argv - option_count, new_argv,
 333                                count * sizeof(char *));
 334                new_argv -= option_count;
 335
 336                if (count < 1)
 337                        die("empty alias for %s", alias_command);
 338
 339                if (!strcmp(alias_command, new_argv[0]))
 340                        die("recursive alias: %s", alias_command);
 341
 342                trace_argv_printf(new_argv,
 343                                  "trace: alias expansion: %s =>",
 344                                  alias_command);
 345
 346                REALLOC_ARRAY(new_argv, count + *argcp);
 347                /* insert after command name */
 348                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 349
 350                *argv = new_argv;
 351                *argcp += count - 1;
 352
 353                ret = 1;
 354        }
 355
 356        errno = saved_errno;
 357
 358        return ret;
 359}
 360
 361static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 362{
 363        int status, help;
 364        struct stat st;
 365        const char *prefix;
 366
 367        prefix = NULL;
 368        help = argc == 2 && !strcmp(argv[1], "-h");
 369        if (!help) {
 370                if (p->option & RUN_SETUP)
 371                        prefix = setup_git_directory();
 372                else if (p->option & RUN_SETUP_GENTLY) {
 373                        int nongit_ok;
 374                        prefix = setup_git_directory_gently(&nongit_ok);
 375                }
 376
 377                if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY) &&
 378                    !(p->option & DELAY_PAGER_CONFIG))
 379                        use_pager = check_pager_config(p->cmd);
 380                if (use_pager == -1 && p->option & USE_PAGER)
 381                        use_pager = 1;
 382
 383                if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 384                    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 385                        trace_repo_setup(prefix);
 386        }
 387        commit_pager_choice();
 388
 389        if (!help && get_super_prefix()) {
 390                if (!(p->option & SUPPORT_SUPER_PREFIX))
 391                        die("%s doesn't support --super-prefix", p->cmd);
 392        }
 393
 394        if (!help && p->option & NEED_WORK_TREE)
 395                setup_work_tree();
 396
 397        trace_argv_printf(argv, "trace: built-in: git");
 398
 399        status = p->fn(argc, argv, prefix);
 400        if (status)
 401                return status;
 402
 403        /* Somebody closed stdout? */
 404        if (fstat(fileno(stdout), &st))
 405                return 0;
 406        /* Ignore write errors for pipes and sockets.. */
 407        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 408                return 0;
 409
 410        /* Check for ENOSPC and EIO errors.. */
 411        if (fflush(stdout))
 412                die_errno("write failure on standard output");
 413        if (ferror(stdout))
 414                die("unknown write failure on standard output");
 415        if (fclose(stdout))
 416                die_errno("close failed on standard output");
 417        return 0;
 418}
 419
 420static struct cmd_struct commands[] = {
 421        { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 422        { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 423        { "annotate", cmd_annotate, RUN_SETUP | NO_PARSEOPT },
 424        { "apply", cmd_apply, RUN_SETUP_GENTLY },
 425        { "archive", cmd_archive, RUN_SETUP_GENTLY },
 426        { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 427        { "blame", cmd_blame, RUN_SETUP },
 428        { "branch", cmd_branch, RUN_SETUP | DELAY_PAGER_CONFIG },
 429        { "bundle", cmd_bundle, RUN_SETUP_GENTLY | NO_PARSEOPT },
 430        { "cat-file", cmd_cat_file, RUN_SETUP },
 431        { "check-attr", cmd_check_attr, RUN_SETUP },
 432        { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 433        { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 434        { "check-ref-format", cmd_check_ref_format, NO_PARSEOPT  },
 435        { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 436        { "checkout-index", cmd_checkout_index,
 437                RUN_SETUP | NEED_WORK_TREE},
 438        { "cherry", cmd_cherry, RUN_SETUP },
 439        { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 440        { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 441        { "clone", cmd_clone },
 442        { "column", cmd_column, RUN_SETUP_GENTLY },
 443        { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 444        { "commit-tree", cmd_commit_tree, RUN_SETUP | NO_PARSEOPT },
 445        { "config", cmd_config, RUN_SETUP_GENTLY | DELAY_PAGER_CONFIG },
 446        { "count-objects", cmd_count_objects, RUN_SETUP },
 447        { "credential", cmd_credential, RUN_SETUP_GENTLY | NO_PARSEOPT },
 448        { "describe", cmd_describe, RUN_SETUP },
 449        { "diff", cmd_diff, NO_PARSEOPT },
 450        { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 451        { "diff-index", cmd_diff_index, RUN_SETUP | NO_PARSEOPT },
 452        { "diff-tree", cmd_diff_tree, RUN_SETUP | NO_PARSEOPT },
 453        { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 454        { "fast-export", cmd_fast_export, RUN_SETUP },
 455        { "fetch", cmd_fetch, RUN_SETUP },
 456        { "fetch-pack", cmd_fetch_pack, RUN_SETUP | NO_PARSEOPT },
 457        { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 458        { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 459        { "format-patch", cmd_format_patch, RUN_SETUP },
 460        { "fsck", cmd_fsck, RUN_SETUP },
 461        { "fsck-objects", cmd_fsck, RUN_SETUP },
 462        { "gc", cmd_gc, RUN_SETUP },
 463        { "get-tar-commit-id", cmd_get_tar_commit_id, NO_PARSEOPT },
 464        { "grep", cmd_grep, RUN_SETUP_GENTLY },
 465        { "hash-object", cmd_hash_object },
 466        { "help", cmd_help },
 467        { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY | NO_PARSEOPT },
 468        { "init", cmd_init_db },
 469        { "init-db", cmd_init_db },
 470        { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 471        { "log", cmd_log, RUN_SETUP },
 472        { "ls-files", cmd_ls_files, RUN_SETUP },
 473        { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 474        { "ls-tree", cmd_ls_tree, RUN_SETUP },
 475        { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY | NO_PARSEOPT },
 476        { "mailsplit", cmd_mailsplit, NO_PARSEOPT },
 477        { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 478        { "merge-base", cmd_merge_base, RUN_SETUP },
 479        { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 480        { "merge-index", cmd_merge_index, RUN_SETUP | NO_PARSEOPT },
 481        { "merge-ours", cmd_merge_ours, RUN_SETUP | NO_PARSEOPT },
 482        { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 483        { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 484        { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 485        { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE | NO_PARSEOPT },
 486        { "merge-tree", cmd_merge_tree, RUN_SETUP | NO_PARSEOPT },
 487        { "mktag", cmd_mktag, RUN_SETUP | NO_PARSEOPT },
 488        { "mktree", cmd_mktree, RUN_SETUP },
 489        { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 490        { "name-rev", cmd_name_rev, RUN_SETUP },
 491        { "notes", cmd_notes, RUN_SETUP },
 492        { "pack-objects", cmd_pack_objects, RUN_SETUP },
 493        { "pack-redundant", cmd_pack_redundant, RUN_SETUP | NO_PARSEOPT },
 494        { "pack-refs", cmd_pack_refs, RUN_SETUP },
 495        { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY | NO_PARSEOPT },
 496        { "pickaxe", cmd_blame, RUN_SETUP },
 497        { "prune", cmd_prune, RUN_SETUP },
 498        { "prune-packed", cmd_prune_packed, RUN_SETUP },
 499        { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 500        { "push", cmd_push, RUN_SETUP },
 501        { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 502        { "rebase--helper", cmd_rebase__helper, RUN_SETUP | NEED_WORK_TREE },
 503        { "receive-pack", cmd_receive_pack },
 504        { "reflog", cmd_reflog, RUN_SETUP },
 505        { "remote", cmd_remote, RUN_SETUP },
 506        { "remote-ext", cmd_remote_ext, NO_PARSEOPT },
 507        { "remote-fd", cmd_remote_fd, NO_PARSEOPT },
 508        { "repack", cmd_repack, RUN_SETUP },
 509        { "replace", cmd_replace, RUN_SETUP },
 510        { "rerere", cmd_rerere, RUN_SETUP },
 511        { "reset", cmd_reset, RUN_SETUP },
 512        { "rev-list", cmd_rev_list, RUN_SETUP | NO_PARSEOPT },
 513        { "rev-parse", cmd_rev_parse, NO_PARSEOPT },
 514        { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 515        { "rm", cmd_rm, RUN_SETUP },
 516        { "send-pack", cmd_send_pack, RUN_SETUP },
 517        { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 518        { "show", cmd_show, RUN_SETUP },
 519        { "show-branch", cmd_show_branch, RUN_SETUP },
 520        { "show-ref", cmd_show_ref, RUN_SETUP },
 521        { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 522        { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 523        { "stripspace", cmd_stripspace },
 524        { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX | NO_PARSEOPT },
 525        { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 526        { "tag", cmd_tag, RUN_SETUP | DELAY_PAGER_CONFIG },
 527        { "unpack-file", cmd_unpack_file, RUN_SETUP | NO_PARSEOPT },
 528        { "unpack-objects", cmd_unpack_objects, RUN_SETUP | NO_PARSEOPT },
 529        { "update-index", cmd_update_index, RUN_SETUP },
 530        { "update-ref", cmd_update_ref, RUN_SETUP },
 531        { "update-server-info", cmd_update_server_info, RUN_SETUP },
 532        { "upload-archive", cmd_upload_archive, NO_PARSEOPT },
 533        { "upload-archive--writer", cmd_upload_archive_writer, NO_PARSEOPT },
 534        { "var", cmd_var, RUN_SETUP_GENTLY | NO_PARSEOPT },
 535        { "verify-commit", cmd_verify_commit, RUN_SETUP },
 536        { "verify-pack", cmd_verify_pack },
 537        { "verify-tag", cmd_verify_tag, RUN_SETUP },
 538        { "version", cmd_version },
 539        { "whatchanged", cmd_whatchanged, RUN_SETUP },
 540        { "worktree", cmd_worktree, RUN_SETUP | NO_PARSEOPT },
 541        { "write-tree", cmd_write_tree, RUN_SETUP },
 542};
 543
 544static struct cmd_struct *get_builtin(const char *s)
 545{
 546        int i;
 547        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 548                struct cmd_struct *p = commands + i;
 549                if (!strcmp(s, p->cmd))
 550                        return p;
 551        }
 552        return NULL;
 553}
 554
 555int is_builtin(const char *s)
 556{
 557        return !!get_builtin(s);
 558}
 559
 560static void list_builtins(struct string_list *out, unsigned int exclude_option)
 561{
 562        int i;
 563        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 564                if (exclude_option &&
 565                    (commands[i].option & exclude_option))
 566                        continue;
 567                string_list_append(out, commands[i].cmd);
 568        }
 569}
 570
 571#ifdef STRIP_EXTENSION
 572static void strip_extension(const char **argv)
 573{
 574        size_t len;
 575
 576        if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 577                argv[0] = xmemdupz(argv[0], len);
 578}
 579#else
 580#define strip_extension(cmd)
 581#endif
 582
 583static void handle_builtin(int argc, const char **argv)
 584{
 585        struct argv_array args = ARGV_ARRAY_INIT;
 586        const char *cmd;
 587        struct cmd_struct *builtin;
 588
 589        strip_extension(argv);
 590        cmd = argv[0];
 591
 592        /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 593        if (argc > 1 && !strcmp(argv[1], "--help")) {
 594                int i;
 595
 596                argv[1] = argv[0];
 597                argv[0] = cmd = "help";
 598
 599                for (i = 0; i < argc; i++) {
 600                        argv_array_push(&args, argv[i]);
 601                        if (!i)
 602                                argv_array_push(&args, "--exclude-guides");
 603                }
 604
 605                argc++;
 606                argv = args.argv;
 607        }
 608
 609        builtin = get_builtin(cmd);
 610        if (builtin)
 611                exit(run_builtin(builtin, argc, argv));
 612        argv_array_clear(&args);
 613}
 614
 615static void execv_dashed_external(const char **argv)
 616{
 617        struct child_process cmd = CHILD_PROCESS_INIT;
 618        int status;
 619
 620        if (get_super_prefix())
 621                die("%s doesn't support --super-prefix", argv[0]);
 622
 623        if (use_pager == -1 && !is_builtin(argv[0]))
 624                use_pager = check_pager_config(argv[0]);
 625        commit_pager_choice();
 626
 627        argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 628        argv_array_pushv(&cmd.args, argv + 1);
 629        cmd.clean_on_exit = 1;
 630        cmd.wait_after_clean = 1;
 631        cmd.silent_exec_failure = 1;
 632
 633        trace_argv_printf(cmd.args.argv, "trace: exec:");
 634
 635        /*
 636         * If we fail because the command is not found, it is
 637         * OK to return. Otherwise, we just pass along the status code,
 638         * or our usual generic code if we were not even able to exec
 639         * the program.
 640         */
 641        status = run_command(&cmd);
 642        if (status >= 0)
 643                exit(status);
 644        else if (errno != ENOENT)
 645                exit(128);
 646}
 647
 648static int run_argv(int *argcp, const char ***argv)
 649{
 650        int done_alias = 0;
 651
 652        while (1) {
 653                /*
 654                 * If we tried alias and futzed with our environment,
 655                 * it no longer is safe to invoke builtins directly in
 656                 * general.  We have to spawn them as dashed externals.
 657                 *
 658                 * NEEDSWORK: if we can figure out cases
 659                 * where it is safe to do, we can avoid spawning a new
 660                 * process.
 661                 */
 662                if (!done_alias)
 663                        handle_builtin(*argcp, *argv);
 664
 665                /* .. then try the external ones */
 666                execv_dashed_external(*argv);
 667
 668                /* It could be an alias -- this works around the insanity
 669                 * of overriding "git log" with "git show" by having
 670                 * alias.log = show
 671                 */
 672                if (done_alias)
 673                        break;
 674                if (!handle_alias(argcp, argv))
 675                        break;
 676                done_alias = 1;
 677        }
 678
 679        return done_alias;
 680}
 681
 682int cmd_main(int argc, const char **argv)
 683{
 684        const char *cmd;
 685        int done_help = 0;
 686
 687        cmd = argv[0];
 688        if (!cmd)
 689                cmd = "git-help";
 690        else {
 691                const char *slash = find_last_dir_sep(cmd);
 692                if (slash)
 693                        cmd = slash + 1;
 694        }
 695
 696        trace_command_performance(argv);
 697
 698        /*
 699         * "git-xxxx" is the same as "git xxxx", but we obviously:
 700         *
 701         *  - cannot take flags in between the "git" and the "xxxx".
 702         *  - cannot execute it externally (since it would just do
 703         *    the same thing over again)
 704         *
 705         * So we just directly call the builtin handler, and die if
 706         * that one cannot handle it.
 707         */
 708        if (skip_prefix(cmd, "git-", &cmd)) {
 709                argv[0] = cmd;
 710                handle_builtin(argc, argv);
 711                die("cannot handle %s as a builtin", cmd);
 712        }
 713
 714        /* Look for flags.. */
 715        argv++;
 716        argc--;
 717        handle_options(&argv, &argc, NULL);
 718        if (argc > 0) {
 719                /* translate --help and --version into commands */
 720                skip_prefix(argv[0], "--", &argv[0]);
 721        } else {
 722                /* The user didn't specify a command; give them help */
 723                commit_pager_choice();
 724                printf("usage: %s\n\n", git_usage_string);
 725                list_common_cmds_help();
 726                printf("\n%s\n", _(git_more_info_string));
 727                exit(1);
 728        }
 729        cmd = argv[0];
 730
 731        /*
 732         * We use PATH to find git commands, but we prepend some higher
 733         * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 734         * environment, and the $(gitexecdir) from the Makefile at build
 735         * time.
 736         */
 737        setup_path();
 738
 739        while (1) {
 740                int was_alias = run_argv(&argc, &argv);
 741                if (errno != ENOENT)
 742                        break;
 743                if (was_alias) {
 744                        fprintf(stderr, _("expansion of alias '%s' failed; "
 745                                          "'%s' is not a git command\n"),
 746                                cmd, argv[0]);
 747                        exit(1);
 748                }
 749                if (!done_help) {
 750                        cmd = argv[0] = help_unknown_cmd(cmd);
 751                        done_help = 1;
 752                } else
 753                        break;
 754        }
 755
 756        fprintf(stderr, _("failed to run command '%s': %s\n"),
 757                cmd, strerror(errno));
 758
 759        return 1;
 760}