git.c

   1 #include "builtin.h"
   2 #include "exec_cmd.h"
   3 #include "cache.h"
   4 #include "quote.h"
   5 #include "run-command.h"
   6
   7 const char git_usage_string[] =
   8         "git [--version] [--exec-path[=GIT_EXEC_PATH]] [--html-path]\n"
   9         "           [-p|--paginate|--no-pager]\n"
  10         "           [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE]\n"
  11         "           [--help] COMMAND [ARGS]";
  12
  13 const char git_more_info_string[] =
  14         "See 'git help COMMAND' for more information on a specific command.";
  15
  16 static int use_pager = -1;
  17 struct pager_config {
  18         const char *cmd;
  19         int val;
  20 };
  21
  22 static int pager_command_config(const char *var, const char *value, void *data)
  23 {
  24         struct pager_config *c = data;
  25         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  26                 c->val = git_config_bool(var, value);
  27         return 0;
  28 }
  29
  30 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  31 int check_pager_config(const char *cmd)
  32 {
  33         struct pager_config c;
  34         c.cmd = cmd;
  35         c.val = -1;
  36         git_config(pager_command_config, &c);
  37         return c.val;
  38 }
  39
  40 static void commit_pager_choice(void) {
  41         switch (use_pager) {
  42         case 0:
  43                 setenv("GIT_PAGER", "cat", 1);
  44                 break;
  45         case 1:
  46                 setup_pager();
  47                 break;
  48         default:
  49                 break;
  50         }
  51 }
  52
  53 static int handle_options(const char ***argv, int *argc, int *envchanged)
  54 {
  55         int handled = 0;
  56
  57         while (*argc > 0) {
  58                 const char *cmd = (*argv)[0];
  59                 if (cmd[0] != '-')
  60                         break;
  61
  62                 /*
  63                  * For legacy reasons, the "version" and "help"
  64                  * commands can be written with "--" prepended
  65                  * to make them look like flags.
  66                  */
  67                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  68                         break;
  69
  70                 /*
  71                  * Check remaining flags.
  72                  */
  73                 if (!prefixcmp(cmd, "--exec-path")) {
  74                         cmd += 11;
  75                         if (*cmd == '=')
  76                                 git_set_argv_exec_path(cmd + 1);
  77                         else {
  78                                 puts(git_exec_path());
  79                                 exit(0);
  80                         }
  81                 } else if (!strcmp(cmd, "--html-path")) {
  82                         puts(system_path(GIT_HTML_PATH));
  83                         exit(0);
  84                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  85                         use_pager = 1;
  86                 } else if (!strcmp(cmd, "--no-pager")) {
  87                         use_pager = 0;
  88                         if (envchanged)
  89                                 *envchanged = 1;
  90                 } else if (!strcmp(cmd, "--git-dir")) {
  91                         if (*argc < 2) {
  92                                 fprintf(stderr, "No directory given for --git-dir.\n" );
  93                                 usage(git_usage_string);
  94                         }
  95                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
  96                         if (envchanged)
  97                                 *envchanged = 1;
  98                         (*argv)++;
  99                         (*argc)--;
 100                         handled++;
 101                 } else if (!prefixcmp(cmd, "--git-dir=")) {
 102                         setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
 103                         if (envchanged)
 104                                 *envchanged = 1;
 105                 } else if (!strcmp(cmd, "--work-tree")) {
 106                         if (*argc < 2) {
 107                                 fprintf(stderr, "No directory given for --work-tree.\n" );
 108                                 usage(git_usage_string);
 109                         }
 110                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 111                         if (envchanged)
 112                                 *envchanged = 1;
 113                         (*argv)++;
 114                         (*argc)--;
 115                 } else if (!prefixcmp(cmd, "--work-tree=")) {
 116                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 117                         if (envchanged)
 118                                 *envchanged = 1;
 119                 } else if (!strcmp(cmd, "--bare")) {
 120                         static char git_dir[PATH_MAX+1];
 121                         is_bare_repository_cfg = 1;
 122                         setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
 123                         if (envchanged)
 124                                 *envchanged = 1;
 125                 } else {
 126                         fprintf(stderr, "Unknown option: %s\n", cmd);
 127                         usage(git_usage_string);
 128                 }
 129
 130                 (*argv)++;
 131                 (*argc)--;
 132                 handled++;
 133         }
 134         return handled;
 135 }
 136
 137 static int handle_alias(int *argcp, const char ***argv)
 138 {
 139         int envchanged = 0, ret = 0, saved_errno = errno;
 140         const char *subdir;
 141         int count, option_count;
 142         const char **new_argv;
 143         const char *alias_command;
 144         char *alias_string;
 145         int unused_nongit;
 146
 147         subdir = setup_git_directory_gently(&unused_nongit);
 148
 149         alias_command = (*argv)[0];
 150         alias_string = alias_lookup(alias_command);
 151         if (alias_string) {
 152                 if (alias_string[0] == '!') {
 153                         if (*argcp > 1) {
 154                                 struct strbuf buf;
 155
 156                                 strbuf_init(&buf, PATH_MAX);
 157                                 strbuf_addstr(&buf, alias_string);
 158                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 159                                 free(alias_string);
 160                                 alias_string = buf.buf;
 161                         }
 162                         trace_printf("trace: alias to shell cmd: %s => %s\n",
 163                                      alias_command, alias_string + 1);
 164                         ret = system(alias_string + 1);
 165                         if (ret >= 0 && WIFEXITED(ret) &&
 166                             WEXITSTATUS(ret) != 127)
 167                                 exit(WEXITSTATUS(ret));
 168                         die("Failed to run '%s' when expanding alias '%s'",
 169                             alias_string + 1, alias_command);
 170                 }
 171                 count = split_cmdline(alias_string, &new_argv);
 172                 if (count < 0)
 173                         die("Bad alias.%s string", alias_command);
 174                 option_count = handle_options(&new_argv, &count, &envchanged);
 175                 if (envchanged)
 176                         die("alias '%s' changes environment variables\n"
 177                                  "You can use '!git' in the alias to do this.",
 178                                  alias_command);
 179                 memmove(new_argv - option_count, new_argv,
 180                                 count * sizeof(char *));
 181                 new_argv -= option_count;
 182
 183                 if (count < 1)
 184                         die("empty alias for %s", alias_command);
 185
 186                 if (!strcmp(alias_command, new_argv[0]))
 187                         die("recursive alias: %s", alias_command);
 188
 189                 trace_argv_printf(new_argv,
 190                                   "trace: alias expansion: %s =>",
 191                                   alias_command);
 192
 193                 new_argv = xrealloc(new_argv, sizeof(char *) *
 194                                     (count + *argcp));
 195                 /* insert after command name */
 196                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 197
 198                 *argv = new_argv;
 199                 *argcp += count - 1;
 200
 201                 ret = 1;
 202         }
 203
 204         if (subdir && chdir(subdir))
 205                 die_errno("Cannot change to '%s'", subdir);
 206
 207         errno = saved_errno;
 208
 209         return ret;
 210 }
 211
 212 const char git_version_string[] = GIT_VERSION;
 213
 214 #define RUN_SETUP       (1<<0)
 215 #define USE_PAGER       (1<<1)
 216 /*
 217  * require working tree to be present -- anything uses this needs
 218  * RUN_SETUP for reading from the configuration file.
 219  */
 220 #define NEED_WORK_TREE  (1<<2)
 221
 222 struct cmd_struct {
 223         const char *cmd;
 224         int (*fn)(int, const char **, const char *);
 225         int option;
 226 };
 227
 228 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 229 {
 230         int status;
 231         struct stat st;
 232         const char *prefix;
 233
 234         prefix = NULL;
 235         if (p->option & RUN_SETUP)
 236                 prefix = setup_git_directory();
 237
 238         if (use_pager == -1 && p->option & RUN_SETUP)
 239                 use_pager = check_pager_config(p->cmd);
 240         if (use_pager == -1 && p->option & USE_PAGER)
 241                 use_pager = 1;
 242         commit_pager_choice();
 243
 244         if (p->option & NEED_WORK_TREE)
 245                 setup_work_tree();
 246
 247         trace_argv_printf(argv, "trace: built-in: git");
 248
 249         status = p->fn(argc, argv, prefix);
 250         if (status)
 251                 return status;
 252
 253         /* Somebody closed stdout? */
 254         if (fstat(fileno(stdout), &st))
 255                 return 0;
 256         /* Ignore write errors for pipes and sockets.. */
 257         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 258                 return 0;
 259
 260         /* Check for ENOSPC and EIO errors.. */
 261         if (fflush(stdout))
 262                 die_errno("write failure on standard output");
 263         if (ferror(stdout))
 264                 die("unknown write failure on standard output");
 265         if (fclose(stdout))
 266                 die_errno("close failed on standard output");
 267         return 0;
 268 }
 269
 270 static void handle_internal_command(int argc, const char **argv)
 271 {
 272         const char *cmd = argv[0];
 273         static struct cmd_struct commands[] = {
 274                 { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 275                 { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 276                 { "annotate", cmd_annotate, RUN_SETUP },
 277                 { "apply", cmd_apply },
 278                 { "archive", cmd_archive },
 279                 { "bisect--helper", cmd_bisect__helper, RUN_SETUP | NEED_WORK_TREE },
 280                 { "blame", cmd_blame, RUN_SETUP },
 281                 { "branch", cmd_branch, RUN_SETUP },
 282                 { "bundle", cmd_bundle },
 283                 { "cat-file", cmd_cat_file, RUN_SETUP },
 284                 { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 285                 { "checkout-index", cmd_checkout_index,
 286                         RUN_SETUP | NEED_WORK_TREE},
 287                 { "check-ref-format", cmd_check_ref_format },
 288                 { "check-attr", cmd_check_attr, RUN_SETUP },
 289                 { "cherry", cmd_cherry, RUN_SETUP },
 290                 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 291                 { "clone", cmd_clone },
 292                 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 293                 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 294                 { "commit-tree", cmd_commit_tree, RUN_SETUP },
 295                 { "config", cmd_config },
 296                 { "count-objects", cmd_count_objects, RUN_SETUP },
 297                 { "describe", cmd_describe, RUN_SETUP },
 298                 { "diff", cmd_diff },
 299                 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 300                 { "diff-index", cmd_diff_index, RUN_SETUP },
 301                 { "diff-tree", cmd_diff_tree, RUN_SETUP },
 302                 { "fast-export", cmd_fast_export, RUN_SETUP },
 303                 { "fetch", cmd_fetch, RUN_SETUP },
 304                 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 305                 { "fetch--tool", cmd_fetch__tool, RUN_SETUP },
 306                 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 307                 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 308                 { "format-patch", cmd_format_patch, RUN_SETUP },
 309                 { "fsck", cmd_fsck, RUN_SETUP },
 310                 { "fsck-objects", cmd_fsck, RUN_SETUP },
 311                 { "gc", cmd_gc, RUN_SETUP },
 312                 { "get-tar-commit-id", cmd_get_tar_commit_id },
 313                 { "grep", cmd_grep, RUN_SETUP | USE_PAGER },
 314                 { "help", cmd_help },
 315                 { "init", cmd_init_db },
 316                 { "init-db", cmd_init_db },
 317                 { "log", cmd_log, RUN_SETUP | USE_PAGER },
 318                 { "ls-files", cmd_ls_files, RUN_SETUP },
 319                 { "ls-tree", cmd_ls_tree, RUN_SETUP },
 320                 { "ls-remote", cmd_ls_remote },
 321                 { "mailinfo", cmd_mailinfo },
 322                 { "mailsplit", cmd_mailsplit },
 323                 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 324                 { "merge-base", cmd_merge_base, RUN_SETUP },
 325                 { "merge-file", cmd_merge_file },
 326                 { "merge-ours", cmd_merge_ours, RUN_SETUP },
 327                 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 328                 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 329                 { "mktree", cmd_mktree, RUN_SETUP },
 330                 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 331                 { "name-rev", cmd_name_rev, RUN_SETUP },
 332                 { "pack-objects", cmd_pack_objects, RUN_SETUP },
 333                 { "peek-remote", cmd_ls_remote },
 334                 { "pickaxe", cmd_blame, RUN_SETUP },
 335                 { "prune", cmd_prune, RUN_SETUP },
 336                 { "prune-packed", cmd_prune_packed, RUN_SETUP },
 337                 { "push", cmd_push, RUN_SETUP },
 338                 { "read-tree", cmd_read_tree, RUN_SETUP },
 339                 { "receive-pack", cmd_receive_pack },
 340                 { "reflog", cmd_reflog, RUN_SETUP },
 341                 { "remote", cmd_remote, RUN_SETUP },
 342                 { "replace", cmd_replace, RUN_SETUP },
 343                 { "repo-config", cmd_config },
 344                 { "rerere", cmd_rerere, RUN_SETUP },
 345                 { "reset", cmd_reset, RUN_SETUP },
 346                 { "rev-list", cmd_rev_list, RUN_SETUP },
 347                 { "rev-parse", cmd_rev_parse },
 348                 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 349                 { "rm", cmd_rm, RUN_SETUP },
 350                 { "send-pack", cmd_send_pack, RUN_SETUP },
 351                 { "shortlog", cmd_shortlog, USE_PAGER },
 352                 { "show-branch", cmd_show_branch, RUN_SETUP },
 353                 { "show", cmd_show, RUN_SETUP | USE_PAGER },
 354                 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 355                 { "stripspace", cmd_stripspace },
 356                 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 357                 { "tag", cmd_tag, RUN_SETUP },
 358                 { "tar-tree", cmd_tar_tree },
 359                 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 360                 { "update-index", cmd_update_index, RUN_SETUP },
 361                 { "update-ref", cmd_update_ref, RUN_SETUP },
 362                 { "update-server-info", cmd_update_server_info, RUN_SETUP },
 363                 { "upload-archive", cmd_upload_archive },
 364                 { "verify-tag", cmd_verify_tag, RUN_SETUP },
 365                 { "version", cmd_version },
 366                 { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
 367                 { "write-tree", cmd_write_tree, RUN_SETUP },
 368                 { "verify-pack", cmd_verify_pack },
 369                 { "show-ref", cmd_show_ref, RUN_SETUP },
 370                 { "pack-refs", cmd_pack_refs, RUN_SETUP },
 371         };
 372         int i;
 373         static const char ext[] = STRIP_EXTENSION;
 374
 375         if (sizeof(ext) > 1) {
 376                 i = strlen(argv[0]) - strlen(ext);
 377                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 378                         char *argv0 = xstrdup(argv[0]);
 379                         argv[0] = cmd = argv0;
 380                         argv0[i] = '\0';
 381                 }
 382         }
 383
 384         /* Turn "git cmd --help" into "git help cmd" */
 385         if (argc > 1 && !strcmp(argv[1], "--help")) {
 386                 argv[1] = argv[0];
 387                 argv[0] = cmd = "help";
 388         }
 389
 390         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 391                 struct cmd_struct *p = commands+i;
 392                 if (strcmp(p->cmd, cmd))
 393                         continue;
 394                 exit(run_builtin(p, argc, argv));
 395         }
 396 }
 397
 398 static void execv_dashed_external(const char **argv)
 399 {
 400         struct strbuf cmd = STRBUF_INIT;
 401         const char *tmp;
 402         int status;
 403
 404         strbuf_addf(&cmd, "git-%s", argv[0]);
 405
 406         /*
 407          * argv[0] must be the git command, but the argv array
 408          * belongs to the caller, and may be reused in
 409          * subsequent loop iterations. Save argv[0] and
 410          * restore it on error.
 411          */
 412         tmp = argv[0];
 413         argv[0] = cmd.buf;
 414
 415         trace_argv_printf(argv, "trace: exec:");
 416
 417         /*
 418          * if we fail because the command is not found, it is
 419          * OK to return. Otherwise, we just pass along the status code.
 420          */
 421         status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE);
 422         if (status >= 0 || errno != ENOENT)
 423                 exit(status);
 424
 425         argv[0] = tmp;
 426
 427         strbuf_release(&cmd);
 428 }
 429
 430 static int run_argv(int *argcp, const char ***argv)
 431 {
 432         int done_alias = 0;
 433
 434         while (1) {
 435                 /* See if it's an internal command */
 436                 handle_internal_command(*argcp, *argv);
 437
 438                 /* .. then try the external ones */
 439                 execv_dashed_external(*argv);
 440
 441                 /* It could be an alias -- this works around the insanity
 442                  * of overriding "git log" with "git show" by having
 443                  * alias.log = show
 444                  */
 445                 if (done_alias || !handle_alias(argcp, argv))
 446                         break;
 447                 done_alias = 1;
 448         }
 449
 450         return done_alias;
 451 }
 452
 453
 454 int main(int argc, const char **argv)
 455 {
 456         const char *cmd;
 457
 458         cmd = git_extract_argv0_path(argv[0]);
 459         if (!cmd)
 460                 cmd = "git-help";
 461
 462         /*
 463          * "git-xxxx" is the same as "git xxxx", but we obviously:
 464          *
 465          *  - cannot take flags in between the "git" and the "xxxx".
 466          *  - cannot execute it externally (since it would just do
 467          *    the same thing over again)
 468          *
 469          * So we just directly call the internal command handler, and
 470          * die if that one cannot handle it.
 471          */
 472         if (!prefixcmp(cmd, "git-")) {
 473                 cmd += 4;
 474                 argv[0] = cmd;
 475                 handle_internal_command(argc, argv);
 476                 die("cannot handle %s internally", cmd);
 477         }
 478
 479         /* Look for flags.. */
 480         argv++;
 481         argc--;
 482         handle_options(&argv, &argc, NULL);
 483         commit_pager_choice();
 484         if (argc > 0) {
 485                 if (!prefixcmp(argv[0], "--"))
 486                         argv[0] += 2;
 487         } else {
 488                 /* The user didn't specify a command; give them help */
 489                 printf("usage: %s\n\n", git_usage_string);
 490                 list_common_cmds_help();
 491                 printf("\n%s\n", git_more_info_string);
 492                 exit(1);
 493         }
 494         cmd = argv[0];
 495
 496         /*
 497          * We use PATH to find git commands, but we prepend some higher
 498          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 499          * environment, and the $(gitexecdir) from the Makefile at build
 500          * time.
 501          */
 502         setup_path();
 503
 504         while (1) {
 505                 static int done_help = 0;
 506                 static int was_alias = 0;
 507                 was_alias = run_argv(&argc, &argv);
 508                 if (errno != ENOENT)
 509                         break;
 510                 if (was_alias) {
 511                         fprintf(stderr, "Expansion of alias '%s' failed; "
 512                                 "'%s' is not a git-command\n",
 513                                 cmd, argv[0]);
 514                         exit(1);
 515                 }
 516                 if (!done_help) {
 517                         cmd = argv[0] = help_unknown_cmd(cmd);
 518                         done_help = 1;
 519                 } else
 520                         break;
 521         }
 522
 523         fprintf(stderr, "Failed to run command '%s': %s\n",
 524                 cmd, strerror(errno));
 525
 526         return 1;
 527 }