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