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