git.con commit travis-ci: check that all build artifacts are .gitignore-d (b92cb86)
   1#include "builtin.h"
   2#include "config.h"
   3#include "exec_cmd.h"
   4#include "help.h"
   5#include "run-command.h"
   6
   7const char git_usage_string[] =
   8        "git [--version] [--help] [-C <path>] [-c name=value]\n"
   9        "           [--exec-path[=<path>]] [--html-path] [--man-path] [--info-path]\n"
  10        "           [-p | --paginate | --no-pager] [--no-replace-objects] [--bare]\n"
  11        "           [--git-dir=<path>] [--work-tree=<path>] [--namespace=<name>]\n"
  12        "           <command> [<args>]";
  13
  14const char git_more_info_string[] =
  15        N_("'git help -a' and 'git help -g' list available subcommands and some\n"
  16           "concept guides. See 'git help <command>' or 'git help <concept>'\n"
  17           "to read about a specific subcommand or concept.");
  18
  19static int use_pager = -1;
  20
  21static void list_builtins(void);
  22
  23static void commit_pager_choice(void) {
  24        switch (use_pager) {
  25        case 0:
  26                setenv("GIT_PAGER", "cat", 1);
  27                break;
  28        case 1:
  29                setup_pager();
  30                break;
  31        default:
  32                break;
  33        }
  34}
  35
  36static int handle_options(const char ***argv, int *argc, int *envchanged)
  37{
  38        const char **orig_argv = *argv;
  39
  40        while (*argc > 0) {
  41                const char *cmd = (*argv)[0];
  42                if (cmd[0] != '-')
  43                        break;
  44
  45                /*
  46                 * For legacy reasons, the "version" and "help"
  47                 * commands can be written with "--" prepended
  48                 * to make them look like flags.
  49                 */
  50                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  51                        break;
  52
  53                /*
  54                 * Check remaining flags.
  55                 */
  56                if (skip_prefix(cmd, "--exec-path", &cmd)) {
  57                        if (*cmd == '=')
  58                                git_set_argv_exec_path(cmd + 1);
  59                        else {
  60                                puts(git_exec_path());
  61                                exit(0);
  62                        }
  63                } else if (!strcmp(cmd, "--html-path")) {
  64                        puts(system_path(GIT_HTML_PATH));
  65                        exit(0);
  66                } else if (!strcmp(cmd, "--man-path")) {
  67                        puts(system_path(GIT_MAN_PATH));
  68                        exit(0);
  69                } else if (!strcmp(cmd, "--info-path")) {
  70                        puts(system_path(GIT_INFO_PATH));
  71                        exit(0);
  72                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  73                        use_pager = 1;
  74                } else if (!strcmp(cmd, "--no-pager")) {
  75                        use_pager = 0;
  76                        if (envchanged)
  77                                *envchanged = 1;
  78                } else if (!strcmp(cmd, "--no-replace-objects")) {
  79                        check_replace_refs = 0;
  80                        setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
  81                        if (envchanged)
  82                                *envchanged = 1;
  83                } else if (!strcmp(cmd, "--git-dir")) {
  84                        if (*argc < 2) {
  85                                fprintf(stderr, "No directory given for --git-dir.\n" );
  86                                usage(git_usage_string);
  87                        }
  88                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
  89                        if (envchanged)
  90                                *envchanged = 1;
  91                        (*argv)++;
  92                        (*argc)--;
  93                } else if (skip_prefix(cmd, "--git-dir=", &cmd)) {
  94                        setenv(GIT_DIR_ENVIRONMENT, cmd, 1);
  95                        if (envchanged)
  96                                *envchanged = 1;
  97                } else if (!strcmp(cmd, "--namespace")) {
  98                        if (*argc < 2) {
  99                                fprintf(stderr, "No namespace given for --namespace.\n" );
 100                                usage(git_usage_string);
 101                        }
 102                        setenv(GIT_NAMESPACE_ENVIRONMENT, (*argv)[1], 1);
 103                        if (envchanged)
 104                                *envchanged = 1;
 105                        (*argv)++;
 106                        (*argc)--;
 107                } else if (skip_prefix(cmd, "--namespace=", &cmd)) {
 108                        setenv(GIT_NAMESPACE_ENVIRONMENT, cmd, 1);
 109                        if (envchanged)
 110                                *envchanged = 1;
 111                } else if (!strcmp(cmd, "--work-tree")) {
 112                        if (*argc < 2) {
 113                                fprintf(stderr, "No directory given for --work-tree.\n" );
 114                                usage(git_usage_string);
 115                        }
 116                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 117                        if (envchanged)
 118                                *envchanged = 1;
 119                        (*argv)++;
 120                        (*argc)--;
 121                } else if (skip_prefix(cmd, "--work-tree=", &cmd)) {
 122                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd, 1);
 123                        if (envchanged)
 124                                *envchanged = 1;
 125                } else if (!strcmp(cmd, "--super-prefix")) {
 126                        if (*argc < 2) {
 127                                fprintf(stderr, "No prefix given for --super-prefix.\n" );
 128                                usage(git_usage_string);
 129                        }
 130                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, (*argv)[1], 1);
 131                        if (envchanged)
 132                                *envchanged = 1;
 133                        (*argv)++;
 134                        (*argc)--;
 135                } else if (skip_prefix(cmd, "--super-prefix=", &cmd)) {
 136                        setenv(GIT_SUPER_PREFIX_ENVIRONMENT, cmd, 1);
 137                        if (envchanged)
 138                                *envchanged = 1;
 139                } else if (!strcmp(cmd, "--bare")) {
 140                        char *cwd = xgetcwd();
 141                        is_bare_repository_cfg = 1;
 142                        setenv(GIT_DIR_ENVIRONMENT, cwd, 0);
 143                        free(cwd);
 144                        setenv(GIT_IMPLICIT_WORK_TREE_ENVIRONMENT, "0", 1);
 145                        if (envchanged)
 146                                *envchanged = 1;
 147                } else if (!strcmp(cmd, "-c")) {
 148                        if (*argc < 2) {
 149                                fprintf(stderr, "-c expects a configuration string\n" );
 150                                usage(git_usage_string);
 151                        }
 152                        git_config_push_parameter((*argv)[1]);
 153                        (*argv)++;
 154                        (*argc)--;
 155                } else if (!strcmp(cmd, "--literal-pathspecs")) {
 156                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "1", 1);
 157                        if (envchanged)
 158                                *envchanged = 1;
 159                } else if (!strcmp(cmd, "--no-literal-pathspecs")) {
 160                        setenv(GIT_LITERAL_PATHSPECS_ENVIRONMENT, "0", 1);
 161                        if (envchanged)
 162                                *envchanged = 1;
 163                } else if (!strcmp(cmd, "--glob-pathspecs")) {
 164                        setenv(GIT_GLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 165                        if (envchanged)
 166                                *envchanged = 1;
 167                } else if (!strcmp(cmd, "--noglob-pathspecs")) {
 168                        setenv(GIT_NOGLOB_PATHSPECS_ENVIRONMENT, "1", 1);
 169                        if (envchanged)
 170                                *envchanged = 1;
 171                } else if (!strcmp(cmd, "--icase-pathspecs")) {
 172                        setenv(GIT_ICASE_PATHSPECS_ENVIRONMENT, "1", 1);
 173                        if (envchanged)
 174                                *envchanged = 1;
 175                } else if (!strcmp(cmd, "--shallow-file")) {
 176                        (*argv)++;
 177                        (*argc)--;
 178                        set_alternate_shallow_file((*argv)[0], 1);
 179                        if (envchanged)
 180                                *envchanged = 1;
 181                } else if (!strcmp(cmd, "-C")) {
 182                        if (*argc < 2) {
 183                                fprintf(stderr, "No directory given for -C.\n" );
 184                                usage(git_usage_string);
 185                        }
 186                        if ((*argv)[1][0]) {
 187                                if (chdir((*argv)[1]))
 188                                        die_errno("Cannot change to '%s'", (*argv)[1]);
 189                                if (envchanged)
 190                                        *envchanged = 1;
 191                        }
 192                        (*argv)++;
 193                        (*argc)--;
 194                } else if (!strcmp(cmd, "--list-builtins")) {
 195                        list_builtins();
 196                        exit(0);
 197                } else {
 198                        fprintf(stderr, "Unknown option: %s\n", cmd);
 199                        usage(git_usage_string);
 200                }
 201
 202                (*argv)++;
 203                (*argc)--;
 204        }
 205        return (*argv) - orig_argv;
 206}
 207
 208static int handle_alias(int *argcp, const char ***argv)
 209{
 210        int envchanged = 0, ret = 0, saved_errno = errno;
 211        int count, option_count;
 212        const char **new_argv;
 213        const char *alias_command;
 214        char *alias_string;
 215
 216        alias_command = (*argv)[0];
 217        alias_string = alias_lookup(alias_command);
 218        if (alias_string) {
 219                if (alias_string[0] == '!') {
 220                        struct child_process child = CHILD_PROCESS_INIT;
 221                        int nongit_ok;
 222
 223                        /* Aliases expect GIT_PREFIX, GIT_DIR etc to be set */
 224                        setup_git_directory_gently(&nongit_ok);
 225
 226                        commit_pager_choice();
 227
 228                        child.use_shell = 1;
 229                        argv_array_push(&child.args, alias_string + 1);
 230                        argv_array_pushv(&child.args, (*argv) + 1);
 231
 232                        ret = run_command(&child);
 233                        if (ret >= 0)   /* normal exit */
 234                                exit(ret);
 235
 236                        die_errno("While expanding alias '%s': '%s'",
 237                            alias_command, alias_string + 1);
 238                }
 239                count = split_cmdline(alias_string, &new_argv);
 240                if (count < 0)
 241                        die("Bad alias.%s string: %s", alias_command,
 242                            split_cmdline_strerror(count));
 243                option_count = handle_options(&new_argv, &count, &envchanged);
 244                if (envchanged)
 245                        die("alias '%s' changes environment variables\n"
 246                                 "You can use '!git' in the alias to do this.",
 247                                 alias_command);
 248                memmove(new_argv - option_count, new_argv,
 249                                count * sizeof(char *));
 250                new_argv -= option_count;
 251
 252                if (count < 1)
 253                        die("empty alias for %s", alias_command);
 254
 255                if (!strcmp(alias_command, new_argv[0]))
 256                        die("recursive alias: %s", alias_command);
 257
 258                trace_argv_printf(new_argv,
 259                                  "trace: alias expansion: %s =>",
 260                                  alias_command);
 261
 262                REALLOC_ARRAY(new_argv, count + *argcp);
 263                /* insert after command name */
 264                memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 265
 266                *argv = new_argv;
 267                *argcp += count - 1;
 268
 269                ret = 1;
 270        }
 271
 272        errno = saved_errno;
 273
 274        return ret;
 275}
 276
 277#define RUN_SETUP               (1<<0)
 278#define RUN_SETUP_GENTLY        (1<<1)
 279#define USE_PAGER               (1<<2)
 280/*
 281 * require working tree to be present -- anything uses this needs
 282 * RUN_SETUP for reading from the configuration file.
 283 */
 284#define NEED_WORK_TREE          (1<<3)
 285#define SUPPORT_SUPER_PREFIX    (1<<4)
 286
 287struct cmd_struct {
 288        const char *cmd;
 289        int (*fn)(int, const char **, const char *);
 290        int option;
 291};
 292
 293static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 294{
 295        int status, help;
 296        struct stat st;
 297        const char *prefix;
 298
 299        prefix = NULL;
 300        help = argc == 2 && !strcmp(argv[1], "-h");
 301        if (!help) {
 302                if (p->option & RUN_SETUP)
 303                        prefix = setup_git_directory();
 304                else if (p->option & RUN_SETUP_GENTLY) {
 305                        int nongit_ok;
 306                        prefix = setup_git_directory_gently(&nongit_ok);
 307                }
 308
 309                if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
 310                        use_pager = check_pager_config(p->cmd);
 311                if (use_pager == -1 && p->option & USE_PAGER)
 312                        use_pager = 1;
 313
 314                if ((p->option & (RUN_SETUP | RUN_SETUP_GENTLY)) &&
 315                    startup_info->have_repository) /* get_git_dir() may set up repo, avoid that */
 316                        trace_repo_setup(prefix);
 317        }
 318        commit_pager_choice();
 319
 320        if (!help && get_super_prefix()) {
 321                if (!(p->option & SUPPORT_SUPER_PREFIX))
 322                        die("%s doesn't support --super-prefix", p->cmd);
 323        }
 324
 325        if (!help && p->option & NEED_WORK_TREE)
 326                setup_work_tree();
 327
 328        trace_argv_printf(argv, "trace: built-in: git");
 329
 330        status = p->fn(argc, argv, prefix);
 331        if (status)
 332                return status;
 333
 334        /* Somebody closed stdout? */
 335        if (fstat(fileno(stdout), &st))
 336                return 0;
 337        /* Ignore write errors for pipes and sockets.. */
 338        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 339                return 0;
 340
 341        /* Check for ENOSPC and EIO errors.. */
 342        if (fflush(stdout))
 343                die_errno("write failure on standard output");
 344        if (ferror(stdout))
 345                die("unknown write failure on standard output");
 346        if (fclose(stdout))
 347                die_errno("close failed on standard output");
 348        return 0;
 349}
 350
 351static struct cmd_struct commands[] = {
 352        { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 353        { "am", cmd_am, RUN_SETUP | NEED_WORK_TREE },
 354        { "annotate", cmd_annotate, RUN_SETUP },
 355        { "apply", cmd_apply, RUN_SETUP_GENTLY },
 356        { "archive", cmd_archive, RUN_SETUP_GENTLY },
 357        { "bisect--helper", cmd_bisect__helper, RUN_SETUP },
 358        { "blame", cmd_blame, RUN_SETUP },
 359        { "branch", cmd_branch, RUN_SETUP },
 360        { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 361        { "cat-file", cmd_cat_file, RUN_SETUP },
 362        { "check-attr", cmd_check_attr, RUN_SETUP },
 363        { "check-ignore", cmd_check_ignore, RUN_SETUP | NEED_WORK_TREE },
 364        { "check-mailmap", cmd_check_mailmap, RUN_SETUP },
 365        { "check-ref-format", cmd_check_ref_format },
 366        { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 367        { "checkout-index", cmd_checkout_index,
 368                RUN_SETUP | NEED_WORK_TREE},
 369        { "cherry", cmd_cherry, RUN_SETUP },
 370        { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 371        { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 372        { "clone", cmd_clone },
 373        { "column", cmd_column, RUN_SETUP_GENTLY },
 374        { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 375        { "commit-tree", cmd_commit_tree, RUN_SETUP },
 376        { "config", cmd_config, RUN_SETUP_GENTLY },
 377        { "count-objects", cmd_count_objects, RUN_SETUP },
 378        { "credential", cmd_credential, RUN_SETUP_GENTLY },
 379        { "describe", cmd_describe, RUN_SETUP },
 380        { "diff", cmd_diff },
 381        { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 382        { "diff-index", cmd_diff_index, RUN_SETUP },
 383        { "diff-tree", cmd_diff_tree, RUN_SETUP },
 384        { "difftool", cmd_difftool, RUN_SETUP | NEED_WORK_TREE },
 385        { "fast-export", cmd_fast_export, RUN_SETUP },
 386        { "fetch", cmd_fetch, RUN_SETUP },
 387        { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 388        { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 389        { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 390        { "format-patch", cmd_format_patch, RUN_SETUP },
 391        { "fsck", cmd_fsck, RUN_SETUP },
 392        { "fsck-objects", cmd_fsck, RUN_SETUP },
 393        { "gc", cmd_gc, RUN_SETUP },
 394        { "get-tar-commit-id", cmd_get_tar_commit_id },
 395        { "grep", cmd_grep, RUN_SETUP_GENTLY | SUPPORT_SUPER_PREFIX },
 396        { "hash-object", cmd_hash_object },
 397        { "help", cmd_help },
 398        { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
 399        { "init", cmd_init_db },
 400        { "init-db", cmd_init_db },
 401        { "interpret-trailers", cmd_interpret_trailers, RUN_SETUP_GENTLY },
 402        { "log", cmd_log, RUN_SETUP },
 403        { "ls-files", cmd_ls_files, RUN_SETUP },
 404        { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 405        { "ls-tree", cmd_ls_tree, RUN_SETUP },
 406        { "mailinfo", cmd_mailinfo, RUN_SETUP_GENTLY },
 407        { "mailsplit", cmd_mailsplit },
 408        { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 409        { "merge-base", cmd_merge_base, RUN_SETUP },
 410        { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 411        { "merge-index", cmd_merge_index, RUN_SETUP },
 412        { "merge-ours", cmd_merge_ours, RUN_SETUP },
 413        { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 414        { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 415        { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 416        { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 417        { "merge-tree", cmd_merge_tree, RUN_SETUP },
 418        { "mktag", cmd_mktag, RUN_SETUP },
 419        { "mktree", cmd_mktree, RUN_SETUP },
 420        { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 421        { "name-rev", cmd_name_rev, RUN_SETUP },
 422        { "notes", cmd_notes, RUN_SETUP },
 423        { "pack-objects", cmd_pack_objects, RUN_SETUP },
 424        { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
 425        { "pack-refs", cmd_pack_refs, RUN_SETUP },
 426        { "patch-id", cmd_patch_id, RUN_SETUP_GENTLY },
 427        { "pickaxe", cmd_blame, RUN_SETUP },
 428        { "prune", cmd_prune, RUN_SETUP },
 429        { "prune-packed", cmd_prune_packed, RUN_SETUP },
 430        { "pull", cmd_pull, RUN_SETUP | NEED_WORK_TREE },
 431        { "push", cmd_push, RUN_SETUP },
 432        { "read-tree", cmd_read_tree, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 433        { "rebase--helper", cmd_rebase__helper, RUN_SETUP | NEED_WORK_TREE },
 434        { "receive-pack", cmd_receive_pack },
 435        { "reflog", cmd_reflog, RUN_SETUP },
 436        { "remote", cmd_remote, RUN_SETUP },
 437        { "remote-ext", cmd_remote_ext },
 438        { "remote-fd", cmd_remote_fd },
 439        { "repack", cmd_repack, RUN_SETUP },
 440        { "replace", cmd_replace, RUN_SETUP },
 441        { "rerere", cmd_rerere, RUN_SETUP },
 442        { "reset", cmd_reset, RUN_SETUP },
 443        { "rev-list", cmd_rev_list, RUN_SETUP },
 444        { "rev-parse", cmd_rev_parse },
 445        { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 446        { "rm", cmd_rm, RUN_SETUP },
 447        { "send-pack", cmd_send_pack, RUN_SETUP },
 448        { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 449        { "show", cmd_show, RUN_SETUP },
 450        { "show-branch", cmd_show_branch, RUN_SETUP },
 451        { "show-ref", cmd_show_ref, RUN_SETUP },
 452        { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 453        { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 454        { "stripspace", cmd_stripspace },
 455        { "submodule--helper", cmd_submodule__helper, RUN_SETUP | SUPPORT_SUPER_PREFIX},
 456        { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 457        { "tag", cmd_tag, RUN_SETUP },
 458        { "unpack-file", cmd_unpack_file, RUN_SETUP },
 459        { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 460        { "update-index", cmd_update_index, RUN_SETUP },
 461        { "update-ref", cmd_update_ref, RUN_SETUP },
 462        { "update-server-info", cmd_update_server_info, RUN_SETUP },
 463        { "upload-archive", cmd_upload_archive },
 464        { "upload-archive--writer", cmd_upload_archive_writer },
 465        { "var", cmd_var, RUN_SETUP_GENTLY },
 466        { "verify-commit", cmd_verify_commit, RUN_SETUP },
 467        { "verify-pack", cmd_verify_pack },
 468        { "verify-tag", cmd_verify_tag, RUN_SETUP },
 469        { "version", cmd_version },
 470        { "whatchanged", cmd_whatchanged, RUN_SETUP },
 471        { "worktree", cmd_worktree, RUN_SETUP },
 472        { "write-tree", cmd_write_tree, RUN_SETUP },
 473};
 474
 475static struct cmd_struct *get_builtin(const char *s)
 476{
 477        int i;
 478        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 479                struct cmd_struct *p = commands + i;
 480                if (!strcmp(s, p->cmd))
 481                        return p;
 482        }
 483        return NULL;
 484}
 485
 486int is_builtin(const char *s)
 487{
 488        return !!get_builtin(s);
 489}
 490
 491static void list_builtins(void)
 492{
 493        int i;
 494        for (i = 0; i < ARRAY_SIZE(commands); i++)
 495                printf("%s\n", commands[i].cmd);
 496}
 497
 498#ifdef STRIP_EXTENSION
 499static void strip_extension(const char **argv)
 500{
 501        size_t len;
 502
 503        if (strip_suffix(argv[0], STRIP_EXTENSION, &len))
 504                argv[0] = xmemdupz(argv[0], len);
 505}
 506#else
 507#define strip_extension(cmd)
 508#endif
 509
 510static void handle_builtin(int argc, const char **argv)
 511{
 512        struct argv_array args = ARGV_ARRAY_INIT;
 513        const char *cmd;
 514        struct cmd_struct *builtin;
 515
 516        strip_extension(argv);
 517        cmd = argv[0];
 518
 519        /* Turn "git cmd --help" into "git help --exclude-guides cmd" */
 520        if (argc > 1 && !strcmp(argv[1], "--help")) {
 521                int i;
 522
 523                argv[1] = argv[0];
 524                argv[0] = cmd = "help";
 525
 526                for (i = 0; i < argc; i++) {
 527                        argv_array_push(&args, argv[i]);
 528                        if (!i)
 529                                argv_array_push(&args, "--exclude-guides");
 530                }
 531
 532                argc++;
 533                argv = args.argv;
 534        }
 535
 536        builtin = get_builtin(cmd);
 537        if (builtin)
 538                exit(run_builtin(builtin, argc, argv));
 539        argv_array_clear(&args);
 540}
 541
 542static void execv_dashed_external(const char **argv)
 543{
 544        struct child_process cmd = CHILD_PROCESS_INIT;
 545        int status;
 546
 547        if (get_super_prefix())
 548                die("%s doesn't support --super-prefix", argv[0]);
 549
 550        if (use_pager == -1)
 551                use_pager = check_pager_config(argv[0]);
 552        commit_pager_choice();
 553
 554        argv_array_pushf(&cmd.args, "git-%s", argv[0]);
 555        argv_array_pushv(&cmd.args, argv + 1);
 556        cmd.clean_on_exit = 1;
 557        cmd.wait_after_clean = 1;
 558        cmd.silent_exec_failure = 1;
 559
 560        trace_argv_printf(cmd.args.argv, "trace: exec:");
 561
 562        /*
 563         * If we fail because the command is not found, it is
 564         * OK to return. Otherwise, we just pass along the status code,
 565         * or our usual generic code if we were not even able to exec
 566         * the program.
 567         */
 568        status = run_command(&cmd);
 569        if (status >= 0)
 570                exit(status);
 571        else if (errno != ENOENT)
 572                exit(128);
 573}
 574
 575static int run_argv(int *argcp, const char ***argv)
 576{
 577        int done_alias = 0;
 578
 579        while (1) {
 580                /*
 581                 * If we tried alias and futzed with our environment,
 582                 * it no longer is safe to invoke builtins directly in
 583                 * general.  We have to spawn them as dashed externals.
 584                 *
 585                 * NEEDSWORK: if we can figure out cases
 586                 * where it is safe to do, we can avoid spawning a new
 587                 * process.
 588                 */
 589                if (!done_alias)
 590                        handle_builtin(*argcp, *argv);
 591
 592                /* .. then try the external ones */
 593                execv_dashed_external(*argv);
 594
 595                /* It could be an alias -- this works around the insanity
 596                 * of overriding "git log" with "git show" by having
 597                 * alias.log = show
 598                 */
 599                if (done_alias)
 600                        break;
 601                if (!handle_alias(argcp, argv))
 602                        break;
 603                done_alias = 1;
 604        }
 605
 606        return done_alias;
 607}
 608
 609int cmd_main(int argc, const char **argv)
 610{
 611        const char *cmd;
 612        int done_help = 0;
 613
 614        cmd = argv[0];
 615        if (!cmd)
 616                cmd = "git-help";
 617        else {
 618                const char *slash = find_last_dir_sep(cmd);
 619                if (slash)
 620                        cmd = slash + 1;
 621        }
 622
 623        trace_command_performance(argv);
 624
 625        /*
 626         * "git-xxxx" is the same as "git xxxx", but we obviously:
 627         *
 628         *  - cannot take flags in between the "git" and the "xxxx".
 629         *  - cannot execute it externally (since it would just do
 630         *    the same thing over again)
 631         *
 632         * So we just directly call the builtin handler, and die if
 633         * that one cannot handle it.
 634         */
 635        if (skip_prefix(cmd, "git-", &cmd)) {
 636                argv[0] = cmd;
 637                handle_builtin(argc, argv);
 638                die("cannot handle %s as a builtin", cmd);
 639        }
 640
 641        /* Look for flags.. */
 642        argv++;
 643        argc--;
 644        handle_options(&argv, &argc, NULL);
 645        if (argc > 0) {
 646                /* translate --help and --version into commands */
 647                skip_prefix(argv[0], "--", &argv[0]);
 648        } else {
 649                /* The user didn't specify a command; give them help */
 650                commit_pager_choice();
 651                printf("usage: %s\n\n", git_usage_string);
 652                list_common_cmds_help();
 653                printf("\n%s\n", _(git_more_info_string));
 654                exit(1);
 655        }
 656        cmd = argv[0];
 657
 658        /*
 659         * We use PATH to find git commands, but we prepend some higher
 660         * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 661         * environment, and the $(gitexecdir) from the Makefile at build
 662         * time.
 663         */
 664        setup_path();
 665
 666        while (1) {
 667                int was_alias = run_argv(&argc, &argv);
 668                if (errno != ENOENT)
 669                        break;
 670                if (was_alias) {
 671                        fprintf(stderr, "Expansion of alias '%s' failed; "
 672                                "'%s' is not a git command\n",
 673                                cmd, argv[0]);
 674                        exit(1);
 675                }
 676                if (!done_help) {
 677                        cmd = argv[0] = help_unknown_cmd(cmd);
 678                        done_help = 1;
 679                } else
 680                        break;
 681        }
 682
 683        fprintf(stderr, "Failed to run command '%s': %s\n",
 684                cmd, strerror(errno));
 685
 686        return 1;
 687}