git.c

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