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