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