Andrew's git / gitweb.git / git.c
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git.con commit merge-file: handle empty files gracefully (381b851)
   1#include "builtin.h"
   2#include "exec_cmd.h"
   3#include "cache.h"
   4#include "quote.h"
   5
   6const 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
   9static int handle_options(const char*** argv, int* argc, int* envchanged)
  10{
  11        int handled = 0;
  12
  13        while (*argc > 0) {
  14                const char *cmd = (*argv)[0];
  15                if (cmd[0] != '-')
  16                        break;
  17
  18                /*
  19                 * For legacy reasons, the "version" and "help"
  20                 * commands can be written with "--" prepended
  21                 * to make them look like flags.
  22                 */
  23                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  24                        break;
  25
  26                /*
  27                 * Check remaining flags.
  28                 */
  29                if (!prefixcmp(cmd, "--exec-path")) {
  30                        cmd += 11;
  31                        if (*cmd == '=')
  32                                git_set_argv_exec_path(cmd + 1);
  33                        else {
  34                                puts(git_exec_path());
  35                                exit(0);
  36                        }
  37                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  38                        setup_pager();
  39                } else if (!strcmp(cmd, "--no-pager")) {
  40                        setenv("GIT_PAGER", "cat", 1);
  41                        if (envchanged)
  42                                *envchanged = 1;
  43                } else if (!strcmp(cmd, "--git-dir")) {
  44                        if (*argc < 2) {
  45                                fprintf(stderr, "No directory given for --git-dir.\n" );
  46                                usage(git_usage_string);
  47                        }
  48                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
  49                        if (envchanged)
  50                                *envchanged = 1;
  51                        (*argv)++;
  52                        (*argc)--;
  53                        handled++;
  54                } else if (!prefixcmp(cmd, "--git-dir=")) {
  55                        setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
  56                        if (envchanged)
  57                                *envchanged = 1;
  58                } else if (!strcmp(cmd, "--work-tree")) {
  59                        if (*argc < 2) {
  60                                fprintf(stderr, "No directory given for --work-tree.\n" );
  61                                usage(git_usage_string);
  62                        }
  63                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
  64                        if (envchanged)
  65                                *envchanged = 1;
  66                        (*argv)++;
  67                        (*argc)--;
  68                } else if (!prefixcmp(cmd, "--work-tree=")) {
  69                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
  70                        if (envchanged)
  71                                *envchanged = 1;
  72                } else if (!strcmp(cmd, "--bare")) {
  73                        static char git_dir[PATH_MAX+1];
  74                        is_bare_repository_cfg = 1;
  75                        setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
  76                        if (envchanged)
  77                                *envchanged = 1;
  78                } else {
  79                        fprintf(stderr, "Unknown option: %s\n", cmd);
  80                        usage(git_usage_string);
  81                }
  82
  83                (*argv)++;
  84                (*argc)--;
  85                handled++;
  86        }
  87        return handled;
  88}
  89
  90static const char *alias_command;
  91static char *alias_string;
  92
  93static int git_alias_config(const char *var, const char *value)
  94{
  95        if (!prefixcmp(var, "alias.") && !strcmp(var + 6, alias_command)) {
  96                if (!value)
  97                        return config_error_nonbool(var);
  98                alias_string = xstrdup(value);
  99        }
 100        return 0;
 101}
 102
 103static int split_cmdline(char *cmdline, const char ***argv)
 104{
 105        int src, dst, count = 0, size = 16;
 106        char quoted = 0;
 107
 108        *argv = xmalloc(sizeof(char*) * size);
 109
 110        /* split alias_string */
 111        (*argv)[count++] = cmdline;
 112        for (src = dst = 0; cmdline[src];) {
 113                char c = cmdline[src];
 114                if (!quoted && isspace(c)) {
 115                        cmdline[dst++] = 0;
 116                        while (cmdline[++src]
 117                                        && isspace(cmdline[src]))
 118                                ; /* skip */
 119                        if (count >= size) {
 120                                size += 16;
 121                                *argv = xrealloc(*argv, sizeof(char*) * size);
 122                        }
 123                        (*argv)[count++] = cmdline + dst;
 124                } else if(!quoted && (c == '\'' || c == '"')) {
 125                        quoted = c;
 126                        src++;
 127                } else if (c == quoted) {
 128                        quoted = 0;
 129                        src++;
 130                } else {
 131                        if (c == '\\' && quoted != '\'') {
 132                                src++;
 133                                c = cmdline[src];
 134                                if (!c) {
 135                                        free(*argv);
 136                                        *argv = NULL;
 137                                        return error("cmdline ends with \\");
 138                                }
 139                        }
 140                        cmdline[dst++] = c;
 141                        src++;
 142                }
 143        }
 144
 145        cmdline[dst] = 0;
 146
 147        if (quoted) {
 148                free(*argv);
 149                *argv = NULL;
 150                return error("unclosed quote");
 151        }
 152
 153        return count;
 154}
 155
 156static int handle_alias(int *argcp, const char ***argv)
 157{
 158        int nongit = 0, envchanged = 0, ret = 0, saved_errno = errno;
 159        const char *subdir;
 160        int count, option_count;
 161        const char** new_argv;
 162
 163        subdir = setup_git_directory_gently(&nongit);
 164
 165        alias_command = (*argv)[0];
 166        git_config(git_alias_config);
 167        if (alias_string) {
 168                if (alias_string[0] == '!') {
 169                        if (*argcp > 1) {
 170                                struct strbuf buf;
 171
 172                                strbuf_init(&buf, PATH_MAX);
 173                                strbuf_addstr(&buf, alias_string);
 174                                sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 175                                free(alias_string);
 176                                alias_string = buf.buf;
 177                        }
 178                        trace_printf("trace: alias to shell cmd: %s => %s\n",
 179                                     alias_command, alias_string + 1);
 180                        ret = system(alias_string + 1);
 181                        if (ret >= 0 && WIFEXITED(ret) &&
 182                            WEXITSTATUS(ret) != 127)
 183                                exit(WEXITSTATUS(ret));
 184                        die("Failed to run '%s' when expanding alias '%s'\n",
 185                            alias_string + 1, alias_command);
 186                }
 187                count = split_cmdline(alias_string, &new_argv);
 188                option_count = handle_options(&new_argv, &count, &envchanged);
 189                if (envchanged)
 190                        die("alias '%s' changes environment variables\n"
 191                                 "You can use '!git' in the alias to do this.",
 192                                 alias_command);
 193                memmove(new_argv - option_count, new_argv,
 194                                count * sizeof(char *));
 195                new_argv -= option_count;
 196
 197                if (count < 1)
 198                        die("empty alias for %s", alias_command);
 199
 200                if (!strcmp(alias_command, new_argv[0]))
 201                        die("recursive alias: %s", alias_command);
 202
 203                trace_argv_printf(new_argv,
 204                                  "trace: alias expansion: %s =>",
 205                                  alias_command);
 206
 207                new_argv = xrealloc(new_argv, sizeof(char*) *
 208                                    (count + *argcp + 1));
 209                /* insert after command name */
 210                memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
 211                new_argv[count+*argcp] = NULL;
 212
 213                *argv = new_argv;
 214                *argcp += count - 1;
 215
 216                ret = 1;
 217        }
 218
 219        if (subdir)
 220                chdir(subdir);
 221
 222        errno = saved_errno;
 223
 224        return ret;
 225}
 226
 227const char git_version_string[] = GIT_VERSION;
 228
 229#define RUN_SETUP       (1<<0)
 230#define USE_PAGER       (1<<1)
 231/*
 232 * require working tree to be present -- anything uses this needs
 233 * RUN_SETUP for reading from the configuration file.
 234 */
 235#define NEED_WORK_TREE  (1<<2)
 236
 237struct cmd_struct {
 238        const char *cmd;
 239        int (*fn)(int, const char **, const char *);
 240        int option;
 241};
 242
 243static int run_command(struct cmd_struct *p, int argc, const char **argv)
 244{
 245        int status;
 246        struct stat st;
 247        const char *prefix;
 248
 249        prefix = NULL;
 250        if (p->option & RUN_SETUP)
 251                prefix = setup_git_directory();
 252        if (p->option & USE_PAGER)
 253                setup_pager();
 254        if (p->option & NEED_WORK_TREE)
 255                setup_work_tree();
 256
 257        trace_argv_printf(argv, "trace: built-in: git");
 258
 259        status = p->fn(argc, argv, prefix);
 260        if (status)
 261                return status & 0xff;
 262
 263        /* Somebody closed stdout? */
 264        if (fstat(fileno(stdout), &st))
 265                return 0;
 266        /* Ignore write errors for pipes and sockets.. */
 267        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 268                return 0;
 269
 270        /* Check for ENOSPC and EIO errors.. */
 271        if (fflush(stdout))
 272                die("write failure on standard output: %s", strerror(errno));
 273        if (ferror(stdout))
 274                die("unknown write failure on standard output");
 275        if (fclose(stdout))
 276                die("close failed on standard output: %s", strerror(errno));
 277        return 0;
 278}
 279
 280static void handle_internal_command(int argc, const char **argv)
 281{
 282        const char *cmd = argv[0];
 283        static struct cmd_struct commands[] = {
 284                { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 285                { "annotate", cmd_annotate, RUN_SETUP },
 286                { "apply", cmd_apply },
 287                { "archive", cmd_archive },
 288                { "blame", cmd_blame, RUN_SETUP },
 289                { "branch", cmd_branch, RUN_SETUP },
 290                { "bundle", cmd_bundle },
 291                { "cat-file", cmd_cat_file, RUN_SETUP },
 292                { "checkout-index", cmd_checkout_index,
 293                        RUN_SETUP | NEED_WORK_TREE},
 294                { "check-ref-format", cmd_check_ref_format },
 295                { "check-attr", cmd_check_attr, RUN_SETUP | NEED_WORK_TREE },
 296                { "cherry", cmd_cherry, RUN_SETUP },
 297                { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 298                { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 299                { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 300                { "commit-tree", cmd_commit_tree, RUN_SETUP },
 301                { "config", cmd_config },
 302                { "count-objects", cmd_count_objects, RUN_SETUP },
 303                { "describe", cmd_describe, RUN_SETUP },
 304                { "diff", cmd_diff },
 305                { "diff-files", cmd_diff_files },
 306                { "diff-index", cmd_diff_index, RUN_SETUP },
 307                { "diff-tree", cmd_diff_tree, RUN_SETUP },
 308                { "fast-export", cmd_fast_export, RUN_SETUP },
 309                { "fetch", cmd_fetch, RUN_SETUP },
 310                { "fetch-pack", cmd_fetch_pack, RUN_SETUP },
 311                { "fetch--tool", cmd_fetch__tool, RUN_SETUP },
 312                { "fmt-merge-msg", cmd_fmt_merge_msg, RUN_SETUP },
 313                { "for-each-ref", cmd_for_each_ref, RUN_SETUP },
 314                { "format-patch", cmd_format_patch, RUN_SETUP },
 315                { "fsck", cmd_fsck, RUN_SETUP },
 316                { "fsck-objects", cmd_fsck, RUN_SETUP },
 317                { "gc", cmd_gc, RUN_SETUP },
 318                { "get-tar-commit-id", cmd_get_tar_commit_id },
 319                { "grep", cmd_grep, RUN_SETUP | USE_PAGER },
 320                { "help", cmd_help },
 321#ifndef NO_CURL
 322                { "http-fetch", cmd_http_fetch, RUN_SETUP },
 323#endif
 324                { "init", cmd_init_db },
 325                { "init-db", cmd_init_db },
 326                { "log", cmd_log, RUN_SETUP | USE_PAGER },
 327                { "ls-files", cmd_ls_files, RUN_SETUP },
 328                { "ls-tree", cmd_ls_tree, RUN_SETUP },
 329                { "ls-remote", cmd_ls_remote },
 330                { "mailinfo", cmd_mailinfo },
 331                { "mailsplit", cmd_mailsplit },
 332                { "merge-base", cmd_merge_base, RUN_SETUP },
 333                { "merge-file", cmd_merge_file },
 334                { "merge-ours", cmd_merge_ours, RUN_SETUP },
 335                { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 336                { "name-rev", cmd_name_rev, RUN_SETUP },
 337                { "pack-objects", cmd_pack_objects, RUN_SETUP },
 338                { "peek-remote", cmd_ls_remote },
 339                { "pickaxe", cmd_blame, RUN_SETUP },
 340                { "prune", cmd_prune, RUN_SETUP },
 341                { "prune-packed", cmd_prune_packed, RUN_SETUP },
 342                { "push", cmd_push, RUN_SETUP },
 343                { "read-tree", cmd_read_tree, RUN_SETUP },
 344                { "reflog", cmd_reflog, RUN_SETUP },
 345                { "repo-config", cmd_config },
 346                { "rerere", cmd_rerere, RUN_SETUP },
 347                { "reset", cmd_reset, RUN_SETUP },
 348                { "rev-list", cmd_rev_list, RUN_SETUP },
 349                { "rev-parse", cmd_rev_parse },
 350                { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 351                { "rm", cmd_rm, RUN_SETUP },
 352                { "send-pack", cmd_send_pack, RUN_SETUP },
 353                { "shortlog", cmd_shortlog, RUN_SETUP | USE_PAGER },
 354                { "show-branch", cmd_show_branch, RUN_SETUP },
 355                { "show", cmd_show, RUN_SETUP | USE_PAGER },
 356                { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 357                { "stripspace", cmd_stripspace },
 358                { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 359                { "tag", cmd_tag, RUN_SETUP },
 360                { "tar-tree", cmd_tar_tree },
 361                { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 362                { "update-index", cmd_update_index, RUN_SETUP },
 363                { "update-ref", cmd_update_ref, RUN_SETUP },
 364                { "upload-archive", cmd_upload_archive },
 365                { "verify-tag", cmd_verify_tag, RUN_SETUP },
 366                { "version", cmd_version },
 367                { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
 368                { "write-tree", cmd_write_tree, RUN_SETUP },
 369                { "verify-pack", cmd_verify_pack },
 370                { "show-ref", cmd_show_ref, RUN_SETUP },
 371                { "pack-refs", cmd_pack_refs, RUN_SETUP },
 372        };
 373        int i;
 374
 375        /* Turn "git cmd --help" into "git help cmd" */
 376        if (argc > 1 && !strcmp(argv[1], "--help")) {
 377                argv[1] = argv[0];
 378                argv[0] = cmd = "help";
 379        }
 380
 381        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 382                struct cmd_struct *p = commands+i;
 383                if (strcmp(p->cmd, cmd))
 384                        continue;
 385                exit(run_command(p, argc, argv));
 386        }
 387}
 388
 389int main(int argc, const char **argv)
 390{
 391        const char *cmd = argv[0] ? argv[0] : "git-help";
 392        char *slash = strrchr(cmd, '/');
 393        const char *cmd_path = NULL;
 394        int done_alias = 0;
 395
 396        /*
 397         * Take the basename of argv[0] as the command
 398         * name, and the dirname as the default exec_path
 399         * if we don't have anything better.
 400         */
 401        if (slash) {
 402                *slash++ = 0;
 403                cmd_path = cmd;
 404                cmd = slash;
 405        }
 406
 407        /*
 408         * "git-xxxx" is the same as "git xxxx", but we obviously:
 409         *
 410         *  - cannot take flags in between the "git" and the "xxxx".
 411         *  - cannot execute it externally (since it would just do
 412         *    the same thing over again)
 413         *
 414         * So we just directly call the internal command handler, and
 415         * die if that one cannot handle it.
 416         */
 417        if (!prefixcmp(cmd, "git-")) {
 418                cmd += 4;
 419                argv[0] = cmd;
 420                handle_internal_command(argc, argv);
 421                die("cannot handle %s internally", cmd);
 422        }
 423
 424        /* Look for flags.. */
 425        argv++;
 426        argc--;
 427        handle_options(&argv, &argc, NULL);
 428        if (argc > 0) {
 429                if (!prefixcmp(argv[0], "--"))
 430                        argv[0] += 2;
 431        } else {
 432                /* The user didn't specify a command; give them help */
 433                printf("usage: %s\n\n", git_usage_string);
 434                list_common_cmds_help();
 435                exit(1);
 436        }
 437        cmd = argv[0];
 438
 439        /*
 440         * We use PATH to find git commands, but we prepend some higher
 441         * precidence paths: the "--exec-path" option, the GIT_EXEC_PATH
 442         * environment, and the $(gitexecdir) from the Makefile at build
 443         * time.
 444         */
 445        setup_path(cmd_path);
 446
 447        while (1) {
 448                /* See if it's an internal command */
 449                handle_internal_command(argc, argv);
 450
 451                /* .. then try the external ones */
 452                execv_git_cmd(argv);
 453
 454                /* It could be an alias -- this works around the insanity
 455                 * of overriding "git log" with "git show" by having
 456                 * alias.log = show
 457                 */
 458                if (done_alias || !handle_alias(&argc, &argv))
 459                        break;
 460                done_alias = 1;
 461        }
 462
 463        if (errno == ENOENT) {
 464                if (done_alias) {
 465                        fprintf(stderr, "Expansion of alias '%s' failed; "
 466                                "'%s' is not a git-command\n",
 467                                cmd, argv[0]);
 468                        exit(1);
 469                }
 470                help_unknown_cmd(cmd);
 471        }
 472
 473        fprintf(stderr, "Failed to run command '%s': %s\n",
 474                cmd, strerror(errno));
 475
 476        return 1;
 477}