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 use_pager = -1;
  13 struct pager_config {
  14         const char *cmd;
  15         int val;
  16 };
  17
  18 static int pager_command_config(const char *var, const char *value, void *data)
  19 {
  20         struct pager_config *c = data;
  21         if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  22                 c->val = git_config_bool(var, value);
  23         return 0;
  24 }
  25
  26 /* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  27 int check_pager_config(const char *cmd)
  28 {
  29         struct pager_config c;
  30         c.cmd = cmd;
  31         c.val = -1;
  32         git_config(pager_command_config, &c);
  33         return c.val;
  34 }
  35
  36 static void commit_pager_choice(void) {
  37         switch (use_pager) {
  38         case 0:
  39                 setenv("GIT_PAGER", "cat", 1);
  40                 break;
  41         case 1:
  42                 setup_pager();
  43                 break;
  44         default:
  45                 break;
  46         }
  47 }
  48
  49 static int handle_options(const char*** argv, int* argc, int* envchanged)
  50 {
  51         int handled = 0;
  52
  53         while (*argc > 0) {
  54                 const char *cmd = (*argv)[0];
  55                 if (cmd[0] != '-')
  56                         break;
  57
  58                 /*
  59                  * For legacy reasons, the "version" and "help"
  60                  * commands can be written with "--" prepended
  61                  * to make them look like flags.
  62                  */
  63                 if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  64                         break;
  65
  66                 /*
  67                  * Check remaining flags.
  68                  */
  69                 if (!prefixcmp(cmd, "--exec-path")) {
  70                         cmd += 11;
  71                         if (*cmd == '=')
  72                                 git_set_argv_exec_path(cmd + 1);
  73                         else {
  74                                 puts(git_exec_path());
  75                                 exit(0);
  76                         }
  77                 } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  78                         use_pager = 1;
  79                 } else if (!strcmp(cmd, "--no-pager")) {
  80                         use_pager = 0;
  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                         handled++;
  94                 } else if (!prefixcmp(cmd, "--git-dir=")) {
  95                         setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
  96                         if (envchanged)
  97                                 *envchanged = 1;
  98                 } else if (!strcmp(cmd, "--work-tree")) {
  99                         if (*argc < 2) {
 100                                 fprintf(stderr, "No directory given for --work-tree.\n" );
 101                                 usage(git_usage_string);
 102                         }
 103                         setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 104                         if (envchanged)
 105                                 *envchanged = 1;
 106                         (*argv)++;
 107                         (*argc)--;
 108                 } else if (!prefixcmp(cmd, "--work-tree=")) {
 109                         setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 110                         if (envchanged)
 111                                 *envchanged = 1;
 112                 } else if (!strcmp(cmd, "--bare")) {
 113                         static char git_dir[PATH_MAX+1];
 114                         is_bare_repository_cfg = 1;
 115                         setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
 116                         if (envchanged)
 117                                 *envchanged = 1;
 118                 } else {
 119                         fprintf(stderr, "Unknown option: %s\n", cmd);
 120                         usage(git_usage_string);
 121                 }
 122
 123                 (*argv)++;
 124                 (*argc)--;
 125                 handled++;
 126         }
 127         return handled;
 128 }
 129
 130 static int handle_alias(int *argcp, const char ***argv)
 131 {
 132         int envchanged = 0, ret = 0, saved_errno = errno;
 133         const char *subdir;
 134         int count, option_count;
 135         const char** new_argv;
 136         const char *alias_command;
 137         char *alias_string;
 138         int unused_nongit;
 139
 140         subdir = setup_git_directory_gently(&unused_nongit);
 141
 142         alias_command = (*argv)[0];
 143         alias_string = alias_lookup(alias_command);
 144         if (alias_string) {
 145                 if (alias_string[0] == '!') {
 146                         if (*argcp > 1) {
 147                                 struct strbuf buf;
 148
 149                                 strbuf_init(&buf, PATH_MAX);
 150                                 strbuf_addstr(&buf, alias_string);
 151                                 sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 152                                 free(alias_string);
 153                                 alias_string = buf.buf;
 154                         }
 155                         trace_printf("trace: alias to shell cmd: %s => %s\n",
 156                                      alias_command, alias_string + 1);
 157                         ret = system(alias_string + 1);
 158                         if (ret >= 0 && WIFEXITED(ret) &&
 159                             WEXITSTATUS(ret) != 127)
 160                                 exit(WEXITSTATUS(ret));
 161                         die("Failed to run '%s' when expanding alias '%s'",
 162                             alias_string + 1, alias_command);
 163                 }
 164                 count = split_cmdline(alias_string, &new_argv);
 165                 if (count < 0)
 166                         die("Bad alias.%s string", alias_command);
 167                 option_count = handle_options(&new_argv, &count, &envchanged);
 168                 if (envchanged)
 169                         die("alias '%s' changes environment variables\n"
 170                                  "You can use '!git' in the alias to do this.",
 171                                  alias_command);
 172                 memmove(new_argv - option_count, new_argv,
 173                                 count * sizeof(char *));
 174                 new_argv -= option_count;
 175
 176                 if (count < 1)
 177                         die("empty alias for %s", alias_command);
 178
 179                 if (!strcmp(alias_command, new_argv[0]))
 180                         die("recursive alias: %s", alias_command);
 181
 182                 trace_argv_printf(new_argv,
 183                                   "trace: alias expansion: %s =>",
 184                                   alias_command);
 185
 186                 new_argv = xrealloc(new_argv, sizeof(char*) *
 187                                     (count + *argcp + 1));
 188                 /* insert after command name */
 189                 memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
 190                 new_argv[count+*argcp] = NULL;
 191
 192                 *argv = new_argv;
 193                 *argcp += count - 1;
 194
 195                 ret = 1;
 196         }
 197
 198         if (subdir && chdir(subdir))
 199                 die("Cannot change to %s: %s", subdir, strerror(errno));
 200
 201         errno = saved_errno;
 202
 203         return ret;
 204 }
 205
 206 const char git_version_string[] = GIT_VERSION;
 207
 208 #define RUN_SETUP       (1<<0)
 209 #define USE_PAGER       (1<<1)
 210 /*
 211  * require working tree to be present -- anything uses this needs
 212  * RUN_SETUP for reading from the configuration file.
 213  */
 214 #define NEED_WORK_TREE  (1<<2)
 215
 216 struct cmd_struct {
 217         const char *cmd;
 218         int (*fn)(int, const char **, const char *);
 219         int option;
 220 };
 221
 222 static int run_command(struct cmd_struct *p, int argc, const char **argv)
 223 {
 224         int status;
 225         struct stat st;
 226         const char *prefix;
 227
 228         prefix = NULL;
 229         if (p->option & RUN_SETUP)
 230                 prefix = setup_git_directory();
 231
 232         if (use_pager == -1 && p->option & RUN_SETUP)
 233                 use_pager = check_pager_config(p->cmd);
 234         if (use_pager == -1 && p->option & USE_PAGER)
 235                 use_pager = 1;
 236         commit_pager_choice();
 237
 238         if (p->option & NEED_WORK_TREE)
 239                 setup_work_tree();
 240
 241         trace_argv_printf(argv, "trace: built-in: git");
 242
 243         status = p->fn(argc, argv, prefix);
 244         if (status)
 245                 return status & 0xff;
 246
 247         /* Somebody closed stdout? */
 248         if (fstat(fileno(stdout), &st))
 249                 return 0;
 250         /* Ignore write errors for pipes and sockets.. */
 251         if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 252                 return 0;
 253
 254         /* Check for ENOSPC and EIO errors.. */
 255         if (fflush(stdout))
 256                 die("write failure on standard output: %s", strerror(errno));
 257         if (ferror(stdout))
 258                 die("unknown write failure on standard output");
 259         if (fclose(stdout))
 260                 die("close failed on standard output: %s", strerror(errno));
 261         return 0;
 262 }
 263
 264 static void handle_internal_command(int argc, const char **argv)
 265 {
 266         const char *cmd = argv[0];
 267         static struct cmd_struct commands[] = {
 268                 { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 269                 { "stage", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 270                 { "annotate", cmd_annotate, RUN_SETUP },
 271                 { "apply", cmd_apply },
 272                 { "archive", cmd_archive },
 273                 { "blame", cmd_blame, RUN_SETUP },
 274                 { "branch", cmd_branch, RUN_SETUP },
 275                 { "bundle", cmd_bundle },
 276                 { "cat-file", cmd_cat_file, RUN_SETUP },
 277                 { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 278                 { "checkout-index", cmd_checkout_index,
 279                         RUN_SETUP | NEED_WORK_TREE},
 280                 { "check-ref-format", cmd_check_ref_format },
 281                 { "check-attr", cmd_check_attr, RUN_SETUP },
 282                 { "cherry", cmd_cherry, RUN_SETUP },
 283                 { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 284                 { "clone", cmd_clone },
 285                 { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 286                 { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 287                 { "commit-tree", cmd_commit_tree, RUN_SETUP },
 288                 { "config", cmd_config },
 289                 { "count-objects", cmd_count_objects, RUN_SETUP },
 290                 { "describe", cmd_describe, RUN_SETUP },
 291                 { "diff", cmd_diff },
 292                 { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 293                 { "diff-index", cmd_diff_index, RUN_SETUP },
 294                 { "diff-tree", cmd_diff_tree, RUN_SETUP },
 295                 { "fast-export", cmd_fast_export, RUN_SETUP },
 296                 { "fetch", cmd_fetch, RUN_SETUP },
 297                 { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 298                 { "fetch--tool", cmd_fetch__tool, RUN_SETUP },
 299                 { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 300                 { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 301                 { "format-patch", cmd_format_patch, RUN_SETUP },
 302                 { "fsck", cmd_fsck, RUN_SETUP },
 303                 { "fsck-objects", cmd_fsck, RUN_SETUP },
 304                 { "gc", cmd_gc, RUN_SETUP },
 305                 { "get-tar-commit-id", cmd_get_tar_commit_id },
 306                 { "grep", cmd_grep, RUN_SETUP | USE_PAGER },
 307                 { "help", cmd_help },
 308 #ifndef NO_CURL
 309                 { "http-fetch", cmd_http_fetch, RUN_SETUP },
 310 #endif
 311                 { "init", cmd_init_db },
 312                 { "init-db", cmd_init_db },
 313                 { "log", cmd_log, RUN_SETUP | USE_PAGER },
 314                 { "ls-files", cmd_ls_files, RUN_SETUP },
 315                 { "ls-tree", cmd_ls_tree, RUN_SETUP },
 316                 { "ls-remote", cmd_ls_remote },
 317                 { "mailinfo", cmd_mailinfo },
 318                 { "mailsplit", cmd_mailsplit },
 319                 { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 320                 { "merge-base", cmd_merge_base, RUN_SETUP },
 321                 { "merge-file", cmd_merge_file },
 322                 { "merge-ours", cmd_merge_ours, RUN_SETUP },
 323                 { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 324                 { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 325                 { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 326                 { "name-rev", cmd_name_rev, RUN_SETUP },
 327                 { "pack-objects", cmd_pack_objects, RUN_SETUP },
 328                 { "peek-remote", cmd_ls_remote },
 329                 { "pickaxe", cmd_blame, RUN_SETUP },
 330                 { "prune", cmd_prune, RUN_SETUP },
 331                 { "prune-packed", cmd_prune_packed, RUN_SETUP },
 332                 { "push", cmd_push, RUN_SETUP },
 333                 { "read-tree", cmd_read_tree, RUN_SETUP },
 334                 { "receive-pack", cmd_receive_pack },
 335                 { "reflog", cmd_reflog, RUN_SETUP },
 336                 { "remote", cmd_remote, RUN_SETUP },
 337                 { "repo-config", cmd_config },
 338                 { "rerere", cmd_rerere, RUN_SETUP },
 339                 { "reset", cmd_reset, RUN_SETUP },
 340                 { "rev-list", cmd_rev_list, RUN_SETUP },
 341                 { "rev-parse", cmd_rev_parse },
 342                 { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 343                 { "rm", cmd_rm, RUN_SETUP },
 344                 { "send-pack", cmd_send_pack, RUN_SETUP },
 345                 { "shortlog", cmd_shortlog, USE_PAGER },
 346                 { "show-branch", cmd_show_branch, RUN_SETUP },
 347                 { "show", cmd_show, RUN_SETUP | USE_PAGER },
 348                 { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 349                 { "stripspace", cmd_stripspace },
 350                 { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 351                 { "tag", cmd_tag, RUN_SETUP },
 352                 { "tar-tree", cmd_tar_tree },
 353                 { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 354                 { "update-index", cmd_update_index, RUN_SETUP },
 355                 { "update-ref", cmd_update_ref, RUN_SETUP },
 356                 { "upload-archive", cmd_upload_archive },
 357                 { "verify-tag", cmd_verify_tag, RUN_SETUP },
 358                 { "version", cmd_version },
 359                 { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
 360                 { "write-tree", cmd_write_tree, RUN_SETUP },
 361                 { "verify-pack", cmd_verify_pack },
 362                 { "show-ref", cmd_show_ref, RUN_SETUP },
 363                 { "pack-refs", cmd_pack_refs, RUN_SETUP },
 364         };
 365         int i;
 366         static const char ext[] = STRIP_EXTENSION;
 367
 368         if (sizeof(ext) > 1) {
 369                 i = strlen(argv[0]) - strlen(ext);
 370                 if (i > 0 && !strcmp(argv[0] + i, ext)) {
 371                         char *argv0 = xstrdup(argv[0]);
 372                         argv[0] = cmd = argv0;
 373                         argv0[i] = '\0';
 374                 }
 375         }
 376
 377         /* Turn "git cmd --help" into "git help cmd" */
 378         if (argc > 1 && !strcmp(argv[1], "--help")) {
 379                 argv[1] = argv[0];
 380                 argv[0] = cmd = "help";
 381         }
 382
 383         for (i = 0; i < ARRAY_SIZE(commands); i++) {
 384                 struct cmd_struct *p = commands+i;
 385                 if (strcmp(p->cmd, cmd))
 386                         continue;
 387                 exit(run_command(p, argc, argv));
 388         }
 389 }
 390
 391 static void execv_dashed_external(const char **argv)
 392 {
 393         struct strbuf cmd = STRBUF_INIT;
 394         const char *tmp;
 395
 396         strbuf_addf(&cmd, "git-%s", argv[0]);
 397
 398         /*
 399          * argv[0] must be the git command, but the argv array
 400          * belongs to the caller, and may be reused in
 401          * subsequent loop iterations. Save argv[0] and
 402          * restore it on error.
 403          */
 404         tmp = argv[0];
 405         argv[0] = cmd.buf;
 406
 407         trace_argv_printf(argv, "trace: exec:");
 408
 409         /* execvp() can only ever return if it fails */
 410         execvp(cmd.buf, (char **)argv);
 411
 412         trace_printf("trace: exec failed: %s\n", strerror(errno));
 413
 414         argv[0] = tmp;
 415
 416         strbuf_release(&cmd);
 417 }
 418
 419
 420 int main(int argc, const char **argv)
 421 {
 422         const char *cmd = argv[0] && *argv[0] ? argv[0] : "git-help";
 423         char *slash = (char *)cmd + strlen(cmd);
 424         int done_alias = 0;
 425
 426         /*
 427          * Take the basename of argv[0] as the command
 428          * name, and the dirname as the default exec_path
 429          * if we don't have anything better.
 430          */
 431         while (cmd <= slash && !is_dir_sep(*slash))
 432                 slash--;
 433         if (cmd <= slash) {
 434                 *slash++ = 0;
 435                 git_set_argv0_path(cmd);
 436                 cmd = slash;
 437         }
 438
 439         /*
 440          * "git-xxxx" is the same as "git xxxx", but we obviously:
 441          *
 442          *  - cannot take flags in between the "git" and the "xxxx".
 443          *  - cannot execute it externally (since it would just do
 444          *    the same thing over again)
 445          *
 446          * So we just directly call the internal command handler, and
 447          * die if that one cannot handle it.
 448          */
 449         if (!prefixcmp(cmd, "git-")) {
 450                 cmd += 4;
 451                 argv[0] = cmd;
 452                 handle_internal_command(argc, argv);
 453                 die("cannot handle %s internally", cmd);
 454         }
 455
 456         /* Look for flags.. */
 457         argv++;
 458         argc--;
 459         handle_options(&argv, &argc, NULL);
 460         commit_pager_choice();
 461         if (argc > 0) {
 462                 if (!prefixcmp(argv[0], "--"))
 463                         argv[0] += 2;
 464         } else {
 465                 /* The user didn't specify a command; give them help */
 466                 printf("usage: %s\n\n", git_usage_string);
 467                 list_common_cmds_help();
 468                 printf("\n%s\n", git_more_info_string);
 469                 exit(1);
 470         }
 471         cmd = argv[0];
 472
 473         /*
 474          * We use PATH to find git commands, but we prepend some higher
 475          * precidence paths: the "--exec-path" option, the GIT_EXEC_PATH
 476          * environment, and the $(gitexecdir) from the Makefile at build
 477          * time.
 478          */
 479         setup_path();
 480
 481         while (1) {
 482                 /* See if it's an internal command */
 483                 handle_internal_command(argc, argv);
 484
 485                 /* .. then try the external ones */
 486                 execv_dashed_external(argv);
 487
 488                 /* It could be an alias -- this works around the insanity
 489                  * of overriding "git log" with "git show" by having
 490                  * alias.log = show
 491                  */
 492                 if (done_alias || !handle_alias(&argc, &argv))
 493                         break;
 494                 done_alias = 1;
 495         }
 496
 497         if (errno == ENOENT) {
 498                 if (done_alias) {
 499                         fprintf(stderr, "Expansion of alias '%s' failed; "
 500                                 "'%s' is not a git-command\n",
 501                                 cmd, argv[0]);
 502                         exit(1);
 503                 }
 504                 argv[0] = help_unknown_cmd(cmd);
 505                 handle_internal_command(argc, argv);
 506                 execv_dashed_external(argv);
 507         }
 508
 509         fprintf(stderr, "Failed to run command '%s': %s\n",
 510                 cmd, strerror(errno));
 511
 512         return 1;
 513 }