git.c

   1 #include "builtin.h"
   2 #include "cache.h"
   3 #include "exec_cmd.h"
   4 #include "help.h"
   5 #include "quote.h"
   6 #include "run-command.h"
   7
   8 const char git_usage_string[] =
   9         "git [--version] [--exec-path[=GIT_EXEC_PATH]] [--html-path]\n"
  10         "           [-p|--paginate|--no-pager] [--no-replace-objects]\n"
  11         "           [--bare] [--git-dir=GIT_DIR] [--work-tree=GIT_WORK_TREE]\n"
  12         "           [-c name=value] [--help]\n"
  13         "           COMMAND [ARGS]";
  14
  15 const char git_more_info_string[] =
  16         "See 'git help COMMAND' for more information on a specific command.";
  17
  18 static struct startup_info git_startup_info;
  19 static int use_pager = -1;
  20 struct pager_config {
  21         const char *cmd;
  22         int val;
  23 };
  24
  25 static int pager_command_config(const char *var, const char *value, void *data)
  26 {
  27         struct pager_config *c = data;
  28         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  29                 c->val = git_config_bool(var, value);
  30         return 0;
  31 }
  32
  33 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  34 int check_pager_config(const char *cmd)
  35 {
  36         struct pager_config c;
  37         c.cmd = cmd;
  38         c.val = -1;
  39         git_config(pager_command_config, &c);
  40         return c.val;
  41 }
  42
  43 static void commit_pager_choice(void) {
  44         switch (use_pager) {
  45         case 0:
  46                 setenv("GIT_PAGER", "cat", 1);
  47                 break;
  48         case 1:
  49                 setup_pager();
  50                 break;
  51         default:
  52                 break;
  53         }
  54 }
  55
  56 static int handle_options(const char ***argv, int *argc, int *envchanged)
  57 {
  58         int handled = 0;
  59
  60         if (!getenv("GIT_ASKPASS") && getenv("SSH_ASKPASS"))
  61                 setenv("GIT_ASKPASS", getenv("SSH_ASKPASS"), 1);
  62
  63         while (*argc > 0) {
  64                 const char *cmd = (*argv)[0];
  65                 if (cmd[0] != '-')
  66                         break;
  67
  68                 /*
  69                  * For legacy reasons, the "version" and "help"
  70                  * commands can be written with "--" prepended
  71                  * to make them look like flags.
  72                  */
  73                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  74                         break;
  75
  76                 /*
  77                  * Check remaining flags.
  78                  */
  79                 if (!prefixcmp(cmd, "--exec-path")) {
  80                         cmd += 11;
  81                         if (*cmd == '=')
  82                                 git_set_argv_exec_path(cmd + 1);
  83                         else {
  84                                 puts(git_exec_path());
  85                                 exit(0);
  86                         }
  87                 } else if (!strcmp(cmd, "--html-path")) {
  88                         puts(system_path(GIT_HTML_PATH));
  89                         exit(0);
  90                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  91                         use_pager = 1;
  92                 } else if (!strcmp(cmd, "--no-pager")) {
  93                         use_pager = 0;
  94                         if (envchanged)
  95                                 *envchanged = 1;
  96                 } else if (!strcmp(cmd, "--no-replace-objects")) {
  97                         read_replace_refs = 0;
  98                         setenv(NO_REPLACE_OBJECTS_ENVIRONMENT, "1", 1);
  99                         if (envchanged)
 100                                 *envchanged = 1;
 101                 } else if (!strcmp(cmd, "--git-dir")) {
 102                         if (*argc < 2) {
 103                                 fprintf(stderr, "No directory given for --git-dir.\n" );
 104                                 usage(git_usage_string);
 105                         }
 106                         setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
 107                         if (envchanged)
 108                                 *envchanged = 1;
 109                         (*argv)++;
 110                         (*argc)--;
 111                         handled++;
 112                 } else if (!prefixcmp(cmd, "--git-dir=")) {
 113                         setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
 114                         if (envchanged)
 115                                 *envchanged = 1;
 116                 } else if (!strcmp(cmd, "--work-tree")) {
 117                         if (*argc < 2) {
 118                                 fprintf(stderr, "No directory given for --work-tree.\n" );
 119                                 usage(git_usage_string);
 120                         }
 121                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 122                         if (envchanged)
 123                                 *envchanged = 1;
 124                         (*argv)++;
 125                         (*argc)--;
 126                 } else if (!prefixcmp(cmd, "--work-tree=")) {
 127                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 128                         if (envchanged)
 129                                 *envchanged = 1;
 130                 } else if (!strcmp(cmd, "--bare")) {
 131                         static char git_dir[PATH_MAX+1];
 132                         is_bare_repository_cfg = 1;
 133                         setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
 134                         if (envchanged)
 135                                 *envchanged = 1;
 136                 } else if (!strcmp(cmd, "-c")) {
 137                         if (*argc < 2) {
 138                                 fprintf(stderr, "-c expects a configuration string\n" );
 139                                 usage(git_usage_string);
 140                         }
 141                         git_config_parse_parameter((*argv)[1]);
 142                         (*argv)++;
 143                         (*argc)--;
 144                 } else {
 145                         fprintf(stderr, "Unknown option: %s\n", cmd);
 146                         usage(git_usage_string);
 147                 }
 148
 149                 (*argv)++;
 150                 (*argc)--;
 151                 handled++;
 152         }
 153         return handled;
 154 }
 155
 156 static int handle_alias(int *argcp, const char ***argv)
 157 {
 158         int envchanged = 0, ret = 0, saved_errno = errno;
 159         const char *subdir;
 160         int count, option_count;
 161         const char **new_argv;
 162         const char *alias_command;
 163         char *alias_string;
 164         int unused_nongit;
 165
 166         subdir = setup_git_directory_gently(&unused_nongit);
 167
 168         alias_command = (*argv)[0];
 169         alias_string = alias_lookup(alias_command);
 170         if (alias_string) {
 171                 if (alias_string[0] == '!') {
 172                         commit_pager_choice();
 173                         if (*argcp > 1) {
 174                                 struct strbuf buf;
 175
 176                                 strbuf_init(&buf, PATH_MAX);
 177                                 strbuf_addstr(&buf, alias_string);
 178                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 179                                 free(alias_string);
 180                                 alias_string = buf.buf;
 181                         }
 182                         trace_printf("trace: alias to shell cmd: %s => %s\n",
 183                                      alias_command, alias_string + 1);
 184                         ret = system(alias_string + 1);
 185                         if (ret >= 0 && WIFEXITED(ret) &&
 186                             WEXITSTATUS(ret) != 127)
 187                                 exit(WEXITSTATUS(ret));
 188                         die("Failed to run '%s' when expanding alias '%s'",
 189                             alias_string + 1, alias_command);
 190                 }
 191                 count = split_cmdline(alias_string, &new_argv);
 192                 if (count < 0)
 193                         die("Bad alias.%s string: %s", alias_command,
 194                             split_cmdline_strerror(count));
 195                 option_count = handle_options(&new_argv, &count, &envchanged);
 196                 if (envchanged)
 197                         die("alias '%s' changes environment variables\n"
 198                                  "You can use '!git' in the alias to do this.",
 199                                  alias_command);
 200                 memmove(new_argv - option_count, new_argv,
 201                                 count * sizeof(char *));
 202                 new_argv -= option_count;
 203
 204                 if (count < 1)
 205                         die("empty alias for %s", alias_command);
 206
 207                 if (!strcmp(alias_command, new_argv[0]))
 208                         die("recursive alias: %s", alias_command);
 209
 210                 trace_argv_printf(new_argv,
 211                                   "trace: alias expansion: %s =>",
 212                                   alias_command);
 213
 214                 new_argv = xrealloc(new_argv, sizeof(char *) *
 215                                     (count + *argcp));
 216                 /* insert after command name */
 217                 memcpy(new_argv + count, *argv + 1, sizeof(char *) * *argcp);
 218
 219                 *argv = new_argv;
 220                 *argcp += count - 1;
 221
 222                 ret = 1;
 223         }
 224
 225         if (subdir && chdir(subdir))
 226                 die_errno("Cannot change to '%s'", subdir);
 227
 228         errno = saved_errno;
 229
 230         return ret;
 231 }
 232
 233 const char git_version_string[] = GIT_VERSION;
 234
 235 #define RUN_SETUP               (1<<0)
 236 #define RUN_SETUP_GENTLY        (1<<1)
 237 #define USE_PAGER               (1<<2)
 238 /*
 239  * require working tree to be present -- anything uses this needs
 240  * RUN_SETUP for reading from the configuration file.
 241  */
 242 #define NEED_WORK_TREE          (1<<3)
 243
 244 struct cmd_struct {
 245         const char *cmd;
 246         int (*fn)(int, const char **, const char *);
 247         int option;
 248 };
 249
 250 static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
 251 {
 252         int status, help;
 253         struct stat st;
 254         const char *prefix;
 255
 256         prefix = NULL;
 257         help = argc == 2 && !strcmp(argv[1], "-h");
 258         if (!help) {
 259                 if (p->option & RUN_SETUP)
 260                         prefix = setup_git_directory();
 261                 if (p->option & RUN_SETUP_GENTLY) {
 262                         int nongit_ok;
 263                         prefix = setup_git_directory_gently(&nongit_ok);
 264                 }
 265
 266                 if (use_pager == -1 && p->option & (RUN_SETUP | RUN_SETUP_GENTLY))
 267                         use_pager = check_pager_config(p->cmd);
 268                 if (use_pager == -1 && p->option & USE_PAGER)
 269                         use_pager = 1;
 270         }
 271         commit_pager_choice();
 272
 273         if (!help && p->option & NEED_WORK_TREE)
 274                 setup_work_tree();
 275
 276         trace_argv_printf(argv, "trace: built-in: git");
 277
 278         status = p->fn(argc, argv, prefix);
 279         if (status)
 280                 return status;
 281
 282         /* Somebody closed stdout? */
 283         if (fstat(fileno(stdout), &st))
 284                 return 0;
 285         /* Ignore write errors for pipes and sockets.. */
 286         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 287                 return 0;
 288
 289         /* Check for ENOSPC and EIO errors.. */
 290         if (fflush(stdout))
 291                 die_errno("write failure on standard output");
 292         if (ferror(stdout))
 293                 die("unknown write failure on standard output");
 294         if (fclose(stdout))
 295                 die_errno("close failed on standard output");
 296         return 0;
 297 }
 298
 299 static void handle_internal_command(int argc, const char **argv)
 300 {
 301         const char *cmd = argv[0];
 302         static struct cmd_struct commands[] = {
 303                 { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 304                 { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 305                 { "annotate", cmd_annotate, RUN_SETUP },
 306                 { "apply", cmd_apply, RUN_SETUP_GENTLY },
 307                 { "archive", cmd_archive },
 308                 { "bisect--helper", cmd_bisect__helper, RUN_SETUP | NEED_WORK_TREE },
 309                 { "blame", cmd_blame, RUN_SETUP },
 310                 { "branch", cmd_branch, RUN_SETUP },
 311                 { "bundle", cmd_bundle, RUN_SETUP_GENTLY },
 312                 { "cat-file", cmd_cat_file, RUN_SETUP },
 313                 { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 314                 { "checkout-index", cmd_checkout_index,
 315                         RUN_SETUP | NEED_WORK_TREE},
 316                 { "check-ref-format", cmd_check_ref_format },
 317                 { "check-attr", cmd_check_attr, RUN_SETUP },
 318                 { "cherry", cmd_cherry, RUN_SETUP },
 319                 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 320                 { "clone", cmd_clone },
 321                 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 322                 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 323                 { "commit-tree", cmd_commit_tree, RUN_SETUP },
 324                 { "config", cmd_config, RUN_SETUP_GENTLY },
 325                 { "count-objects", cmd_count_objects, RUN_SETUP },
 326                 { "describe", cmd_describe, RUN_SETUP },
 327                 { "diff", cmd_diff },
 328                 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 329                 { "diff-index", cmd_diff_index, RUN_SETUP },
 330                 { "diff-tree", cmd_diff_tree, RUN_SETUP },
 331                 { "fast-export", cmd_fast_export, RUN_SETUP },
 332                 { "fetch", cmd_fetch, RUN_SETUP },
 333                 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 334                 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 335                 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 336                 { "format-patch", cmd_format_patch, RUN_SETUP },
 337                 { "fsck", cmd_fsck, RUN_SETUP },
 338                 { "fsck-objects", cmd_fsck, RUN_SETUP },
 339                 { "gc", cmd_gc, RUN_SETUP },
 340                 { "get-tar-commit-id", cmd_get_tar_commit_id },
 341                 { "grep", cmd_grep, RUN_SETUP_GENTLY },
 342                 { "hash-object", cmd_hash_object },
 343                 { "help", cmd_help },
 344                 { "index-pack", cmd_index_pack, RUN_SETUP_GENTLY },
 345                 { "init", cmd_init_db },
 346                 { "init-db", cmd_init_db },
 347                 { "log", cmd_log, RUN_SETUP },
 348                 { "ls-files", cmd_ls_files, RUN_SETUP },
 349                 { "ls-tree", cmd_ls_tree, RUN_SETUP },
 350                 { "ls-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 351                 { "mailinfo", cmd_mailinfo },
 352                 { "mailsplit", cmd_mailsplit },
 353                 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 354                 { "merge-base", cmd_merge_base, RUN_SETUP },
 355                 { "merge-file", cmd_merge_file, RUN_SETUP_GENTLY },
 356                 { "merge-index", cmd_merge_index, RUN_SETUP },
 357                 { "merge-ours", cmd_merge_ours, RUN_SETUP },
 358                 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 359                 { "merge-recursive-ours", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 360                 { "merge-recursive-theirs", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 361                 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 362                 { "merge-tree", cmd_merge_tree, RUN_SETUP },
 363                 { "mktag", cmd_mktag, RUN_SETUP },
 364                 { "mktree", cmd_mktree, RUN_SETUP },
 365                 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 366                 { "name-rev", cmd_name_rev, RUN_SETUP },
 367                 { "notes", cmd_notes, RUN_SETUP },
 368                 { "pack-objects", cmd_pack_objects, RUN_SETUP },
 369                 { "pack-redundant", cmd_pack_redundant, RUN_SETUP },
 370                 { "patch-id", cmd_patch_id },
 371                 { "peek-remote", cmd_ls_remote, RUN_SETUP_GENTLY },
 372                 { "pickaxe", cmd_blame, RUN_SETUP },
 373                 { "prune", cmd_prune, RUN_SETUP },
 374                 { "prune-packed", cmd_prune_packed, RUN_SETUP },
 375                 { "push", cmd_push, RUN_SETUP },
 376                 { "read-tree", cmd_read_tree, RUN_SETUP },
 377                 { "receive-pack", cmd_receive_pack },
 378                 { "reflog", cmd_reflog, RUN_SETUP },
 379                 { "remote", cmd_remote, RUN_SETUP },
 380                 { "replace", cmd_replace, RUN_SETUP },
 381                 { "repo-config", cmd_config, RUN_SETUP_GENTLY },
 382                 { "rerere", cmd_rerere, RUN_SETUP },
 383                 { "reset", cmd_reset, RUN_SETUP },
 384                 { "rev-list", cmd_rev_list, RUN_SETUP },
 385                 { "rev-parse", cmd_rev_parse },
 386                 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 387                 { "rm", cmd_rm, RUN_SETUP },
 388                 { "send-pack", cmd_send_pack, RUN_SETUP },
 389                 { "shortlog", cmd_shortlog, RUN_SETUP_GENTLY | USE_PAGER },
 390                 { "show-branch", cmd_show_branch, RUN_SETUP },
 391                 { "show", cmd_show, RUN_SETUP },
 392                 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 393                 { "stripspace", cmd_stripspace },
 394                 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 395                 { "tag", cmd_tag, RUN_SETUP },
 396                 { "tar-tree", cmd_tar_tree },
 397                 { "unpack-file", cmd_unpack_file, RUN_SETUP },
 398                 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 399                 { "update-index", cmd_update_index, RUN_SETUP },
 400                 { "update-ref", cmd_update_ref, RUN_SETUP },
 401                 { "update-server-info", cmd_update_server_info, RUN_SETUP },
 402                 { "upload-archive", cmd_upload_archive },
 403                 { "var", cmd_var, RUN_SETUP_GENTLY },
 404                 { "verify-tag", cmd_verify_tag, RUN_SETUP },
 405                 { "version", cmd_version },
 406                 { "whatchanged", cmd_whatchanged, RUN_SETUP },
 407                 { "write-tree", cmd_write_tree, RUN_SETUP },
 408                 { "verify-pack", cmd_verify_pack },
 409                 { "show-ref", cmd_show_ref, RUN_SETUP },
 410                 { "pack-refs", cmd_pack_refs, RUN_SETUP },
 411         };
 412         int i;
 413         static const char ext[] = STRIP_EXTENSION;
 414
 415         if (sizeof(ext) > 1) {
 416                 i = strlen(argv[0]) - strlen(ext);
 417                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 418                         char *argv0 = xstrdup(argv[0]);
 419                         argv[0] = cmd = argv0;
 420                         argv0[i] = '\0';
 421                 }
 422         }
 423
 424         /* Turn "git cmd --help" into "git help cmd" */
 425         if (argc > 1 && !strcmp(argv[1], "--help")) {
 426                 argv[1] = argv[0];
 427                 argv[0] = cmd = "help";
 428         }
 429
 430         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 431                 struct cmd_struct *p = commands+i;
 432                 if (strcmp(p->cmd, cmd))
 433                         continue;
 434                 exit(run_builtin(p, argc, argv));
 435         }
 436 }
 437
 438 static void execv_dashed_external(const char **argv)
 439 {
 440         struct strbuf cmd = STRBUF_INIT;
 441         const char *tmp;
 442         int status;
 443
 444         commit_pager_choice();
 445
 446         strbuf_addf(&cmd, "git-%s", argv[0]);
 447
 448         /*
 449          * argv[0] must be the git command, but the argv array
 450          * belongs to the caller, and may be reused in
 451          * subsequent loop iterations. Save argv[0] and
 452          * restore it on error.
 453          */
 454         tmp = argv[0];
 455         argv[0] = cmd.buf;
 456
 457         trace_argv_printf(argv, "trace: exec:");
 458
 459         /*
 460          * if we fail because the command is not found, it is
 461          * OK to return. Otherwise, we just pass along the status code.
 462          */
 463         status = run_command_v_opt(argv, RUN_SILENT_EXEC_FAILURE);
 464         if (status >= 0 || errno != ENOENT)
 465                 exit(status);
 466
 467         argv[0] = tmp;
 468
 469         strbuf_release(&cmd);
 470 }
 471
 472 static int run_argv(int *argcp, const char ***argv)
 473 {
 474         int done_alias = 0;
 475
 476         while (1) {
 477                 /* See if it's an internal command */
 478                 handle_internal_command(*argcp, *argv);
 479
 480                 /* .. then try the external ones */
 481                 execv_dashed_external(*argv);
 482
 483                 /* It could be an alias -- this works around the insanity
 484                  * of overriding "git log" with "git show" by having
 485                  * alias.log = show
 486                  */
 487                 if (done_alias || !handle_alias(argcp, argv))
 488                         break;
 489                 done_alias = 1;
 490         }
 491
 492         return done_alias;
 493 }
 494
 495
 496 int main(int argc, const char **argv)
 497 {
 498         const char *cmd;
 499
 500         startup_info = &git_startup_info;
 501
 502         cmd = git_extract_argv0_path(argv[0]);
 503         if (!cmd)
 504                 cmd = "git-help";
 505
 506         /*
 507          * "git-xxxx" is the same as "git xxxx", but we obviously:
 508          *
 509          *  - cannot take flags in between the "git" and the "xxxx".
 510          *  - cannot execute it externally (since it would just do
 511          *    the same thing over again)
 512          *
 513          * So we just directly call the internal command handler, and
 514          * die if that one cannot handle it.
 515          */
 516         if (!prefixcmp(cmd, "git-")) {
 517                 cmd += 4;
 518                 argv[0] = cmd;
 519                 handle_internal_command(argc, argv);
 520                 die("cannot handle %s internally", cmd);
 521         }
 522
 523         /* Look for flags.. */
 524         argv++;
 525         argc--;
 526         handle_options(&argv, &argc, NULL);
 527         if (argc > 0) {
 528                 if (!prefixcmp(argv[0], "--"))
 529                         argv[0] += 2;
 530         } else {
 531                 /* The user didn't specify a command; give them help */
 532                 commit_pager_choice();
 533                 printf("usage: %s\n\n", git_usage_string);
 534                 list_common_cmds_help();
 535                 printf("\n%s\n", git_more_info_string);
 536                 exit(1);
 537         }
 538         cmd = argv[0];
 539
 540         /*
 541          * We use PATH to find git commands, but we prepend some higher
 542          * precedence paths: the "--exec-path" option, the GIT_EXEC_PATH
 543          * environment, and the $(gitexecdir) from the Makefile at build
 544          * time.
 545          */
 546         setup_path();
 547
 548         while (1) {
 549                 static int done_help = 0;
 550                 static int was_alias = 0;
 551                 was_alias = run_argv(&argc, &argv);
 552                 if (errno != ENOENT)
 553                         break;
 554                 if (was_alias) {
 555                         fprintf(stderr, "Expansion of alias '%s' failed; "
 556                                 "'%s' is not a git command\n",
 557                                 cmd, argv[0]);
 558                         exit(1);
 559                 }
 560                 if (!done_help) {
 561                         cmd = argv[0] = help_unknown_cmd(cmd);
 562                         done_help = 1;
 563                 } else
 564                         break;
 565         }
 566
 567         fprintf(stderr, "Failed to run command '%s': %s\n",
 568                 cmd, strerror(errno));
 569
 570         return 1;
 571 }