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