git.con commit blame: show "previous" information in --porcelain/--incremental format (96e1170)
   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
   9const char git_more_info_string[] =
  10        "See 'git help COMMAND' for more information on a specific command.";
  11
  12static int use_pager = -1;
  13struct pager_config {
  14        const char *cmd;
  15        int val;
  16};
  17
  18static int pager_command_config(const char *var, const char *value, void *data)
  19{
  20        struct pager_config *c = data;
  21        if (!prefixcmp(var, "pager.") && !strcmp(var + 6, c->cmd))
  22                c->val = git_config_bool(var, value);
  23        return 0;
  24}
  25
  26/* returns 0 for "no pager", 1 for "use pager", and -1 for "not specified" */
  27int check_pager_config(const char *cmd)
  28{
  29        struct pager_config c;
  30        c.cmd = cmd;
  31        c.val = -1;
  32        git_config(pager_command_config, &c);
  33        return c.val;
  34}
  35
  36static void commit_pager_choice(void) {
  37        switch (use_pager) {
  38        case 0:
  39                setenv("GIT_PAGER", "cat", 1);
  40                break;
  41        case 1:
  42                setup_pager();
  43                break;
  44        default:
  45                break;
  46        }
  47}
  48
  49static int handle_options(const char*** argv, int* argc, int* envchanged)
  50{
  51        int handled = 0;
  52
  53        while (*argc > 0) {
  54                const char *cmd = (*argv)[0];
  55                if (cmd[0] != '-')
  56                        break;
  57
  58                /*
  59                 * For legacy reasons, the "version" and "help"
  60                 * commands can be written with "--" prepended
  61                 * to make them look like flags.
  62                 */
  63                if (!strcmp(cmd, "--help") || !strcmp(cmd, "--version"))
  64                        break;
  65
  66                /*
  67                 * Check remaining flags.
  68                 */
  69                if (!prefixcmp(cmd, "--exec-path")) {
  70                        cmd += 11;
  71                        if (*cmd == '=')
  72                                git_set_argv_exec_path(cmd + 1);
  73                        else {
  74                                puts(git_exec_path());
  75                                exit(0);
  76                        }
  77                } else if (!strcmp(cmd, "-p") || !strcmp(cmd, "--paginate")) {
  78                        use_pager = 1;
  79                } else if (!strcmp(cmd, "--no-pager")) {
  80                        use_pager = 0;
  81                        if (envchanged)
  82                                *envchanged = 1;
  83                } else if (!strcmp(cmd, "--git-dir")) {
  84                        if (*argc < 2) {
  85                                fprintf(stderr, "No directory given for --git-dir.\n" );
  86                                usage(git_usage_string);
  87                        }
  88                        setenv(GIT_DIR_ENVIRONMENT, (*argv)[1], 1);
  89                        if (envchanged)
  90                                *envchanged = 1;
  91                        (*argv)++;
  92                        (*argc)--;
  93                        handled++;
  94                } else if (!prefixcmp(cmd, "--git-dir=")) {
  95                        setenv(GIT_DIR_ENVIRONMENT, cmd + 10, 1);
  96                        if (envchanged)
  97                                *envchanged = 1;
  98                } else if (!strcmp(cmd, "--work-tree")) {
  99                        if (*argc < 2) {
 100                                fprintf(stderr, "No directory given for --work-tree.\n" );
 101                                usage(git_usage_string);
 102                        }
 103                        setenv(GIT_WORK_TREE_ENVIRONMENT, (*argv)[1], 1);
 104                        if (envchanged)
 105                                *envchanged = 1;
 106                        (*argv)++;
 107                        (*argc)--;
 108                } else if (!prefixcmp(cmd, "--work-tree=")) {
 109                        setenv(GIT_WORK_TREE_ENVIRONMENT, cmd + 12, 1);
 110                        if (envchanged)
 111                                *envchanged = 1;
 112                } else if (!strcmp(cmd, "--bare")) {
 113                        static char git_dir[PATH_MAX+1];
 114                        is_bare_repository_cfg = 1;
 115                        setenv(GIT_DIR_ENVIRONMENT, getcwd(git_dir, sizeof(git_dir)), 0);
 116                        if (envchanged)
 117                                *envchanged = 1;
 118                } else {
 119                        fprintf(stderr, "Unknown option: %s\n", cmd);
 120                        usage(git_usage_string);
 121                }
 122
 123                (*argv)++;
 124                (*argc)--;
 125                handled++;
 126        }
 127        return handled;
 128}
 129
 130static int handle_alias(int *argcp, const char ***argv)
 131{
 132        int envchanged = 0, ret = 0, saved_errno = errno;
 133        const char *subdir;
 134        int count, option_count;
 135        const char** new_argv;
 136        const char *alias_command;
 137        char *alias_string;
 138        int unused_nongit;
 139
 140        subdir = setup_git_directory_gently(&unused_nongit);
 141
 142        alias_command = (*argv)[0];
 143        alias_string = alias_lookup(alias_command);
 144        if (alias_string) {
 145                if (alias_string[0] == '!') {
 146                        if (*argcp > 1) {
 147                                struct strbuf buf;
 148
 149                                strbuf_init(&buf, PATH_MAX);
 150                                strbuf_addstr(&buf, alias_string);
 151                                sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
 152                                free(alias_string);
 153                                alias_string = buf.buf;
 154                        }
 155                        trace_printf("trace: alias to shell cmd: %s => %s\n",
 156                                     alias_command, alias_string + 1);
 157                        ret = system(alias_string + 1);
 158                        if (ret >= 0 && WIFEXITED(ret) &&
 159                            WEXITSTATUS(ret) != 127)
 160                                exit(WEXITSTATUS(ret));
 161                        die("Failed to run '%s' when expanding alias '%s'\n",
 162                            alias_string + 1, alias_command);
 163                }
 164                count = split_cmdline(alias_string, &new_argv);
 165                if (count < 0)
 166                        die("Bad alias.%s string", alias_command);
 167                option_count = handle_options(&new_argv, &count, &envchanged);
 168                if (envchanged)
 169                        die("alias '%s' changes environment variables\n"
 170                                 "You can use '!git' in the alias to do this.",
 171                                 alias_command);
 172                memmove(new_argv - option_count, new_argv,
 173                                count * sizeof(char *));
 174                new_argv -= option_count;
 175
 176                if (count < 1)
 177                        die("empty alias for %s", alias_command);
 178
 179                if (!strcmp(alias_command, new_argv[0]))
 180                        die("recursive alias: %s", alias_command);
 181
 182                trace_argv_printf(new_argv,
 183                                  "trace: alias expansion: %s =>",
 184                                  alias_command);
 185
 186                new_argv = xrealloc(new_argv, sizeof(char*) *
 187                                    (count + *argcp + 1));
 188                /* insert after command name */
 189                memcpy(new_argv + count, *argv + 1, sizeof(char*) * *argcp);
 190                new_argv[count+*argcp] = NULL;
 191
 192                *argv = new_argv;
 193                *argcp += count - 1;
 194
 195                ret = 1;
 196        }
 197
 198        if (subdir)
 199                chdir(subdir);
 200
 201        errno = saved_errno;
 202
 203        return ret;
 204}
 205
 206const char git_version_string[] = GIT_VERSION;
 207
 208#define RUN_SETUP       (1<<0)
 209#define USE_PAGER       (1<<1)
 210/*
 211 * require working tree to be present -- anything uses this needs
 212 * RUN_SETUP for reading from the configuration file.
 213 */
 214#define NEED_WORK_TREE  (1<<2)
 215
 216struct cmd_struct {
 217        const char *cmd;
 218        int (*fn)(int, const char **, const char *);
 219        int option;
 220};
 221
 222static int run_command(struct cmd_struct *p, int argc, const char **argv)
 223{
 224        int status;
 225        struct stat st;
 226        const char *prefix;
 227
 228        prefix = NULL;
 229        if (p->option & RUN_SETUP)
 230                prefix = setup_git_directory();
 231
 232        if (use_pager == -1 && p->option & RUN_SETUP)
 233                use_pager = check_pager_config(p->cmd);
 234        if (use_pager == -1 && p->option & USE_PAGER)
 235                use_pager = 1;
 236        commit_pager_choice();
 237
 238        if (p->option & NEED_WORK_TREE)
 239                setup_work_tree();
 240
 241        trace_argv_printf(argv, "trace: built-in: git");
 242
 243        status = p->fn(argc, argv, prefix);
 244        if (status)
 245                return status & 0xff;
 246
 247        /* Somebody closed stdout? */
 248        if (fstat(fileno(stdout), &st))
 249                return 0;
 250        /* Ignore write errors for pipes and sockets.. */
 251        if (S_ISFIFO(st.st_mode) || S_ISSOCK(st.st_mode))
 252                return 0;
 253
 254        /* Check for ENOSPC and EIO errors.. */
 255        if (fflush(stdout))
 256                die("write failure on standard output: %s", strerror(errno));
 257        if (ferror(stdout))
 258                die("unknown write failure on standard output");
 259        if (fclose(stdout))
 260                die("close failed on standard output: %s", strerror(errno));
 261        return 0;
 262}
 263
 264static void handle_internal_command(int argc, const char **argv)
 265{
 266        const char *cmd = argv[0];
 267        static struct cmd_struct commands[] = {
 268                { "add", cmd_add, RUN_SETUP | NEED_WORK_TREE },
 269                { "annotate", cmd_annotate, RUN_SETUP },
 270                { "apply", cmd_apply },
 271                { "archive", cmd_archive },
 272                { "blame", cmd_blame, RUN_SETUP },
 273                { "branch", cmd_branch, RUN_SETUP },
 274                { "bundle", cmd_bundle },
 275                { "cat-file", cmd_cat_file, RUN_SETUP },
 276                { "checkout", cmd_checkout, RUN_SETUP | NEED_WORK_TREE },
 277                { "checkout-index", cmd_checkout_index,
 278                        RUN_SETUP | NEED_WORK_TREE},
 279                { "check-ref-format", cmd_check_ref_format },
 280                { "check-attr", cmd_check_attr, RUN_SETUP },
 281                { "cherry", cmd_cherry, RUN_SETUP },
 282                { "cherry-pick", cmd_cherry_pick, RUN_SETUP | NEED_WORK_TREE },
 283                { "clone", cmd_clone },
 284                { "clean", cmd_clean, RUN_SETUP | NEED_WORK_TREE },
 285                { "commit", cmd_commit, RUN_SETUP | NEED_WORK_TREE },
 286                { "commit-tree", cmd_commit_tree, RUN_SETUP },
 287                { "config", cmd_config },
 288                { "count-objects", cmd_count_objects, RUN_SETUP },
 289                { "describe", cmd_describe, RUN_SETUP },
 290                { "diff", cmd_diff },
 291                { "diff-files", cmd_diff_files, RUN_SETUP | NEED_WORK_TREE },
 292                { "diff-index", cmd_diff_index, RUN_SETUP },
 293                { "diff-tree", cmd_diff_tree, RUN_SETUP },
 294                { "fast-export", cmd_fast_export, RUN_SETUP },
 295                { "fetch", cmd_fetch, RUN_SETUP },
 296                { "fetch-pack", cmd_fetch_pack, 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#ifndef NO_CURL
 308                { "http-fetch", cmd_http_fetch, RUN_SETUP },
 309#endif
 310                { "init", cmd_init_db },
 311                { "init-db", cmd_init_db },
 312                { "log", cmd_log, RUN_SETUP | USE_PAGER },
 313                { "ls-files", cmd_ls_files, RUN_SETUP },
 314                { "ls-tree", cmd_ls_tree, RUN_SETUP },
 315                { "ls-remote", cmd_ls_remote },
 316                { "mailinfo", cmd_mailinfo },
 317                { "mailsplit", cmd_mailsplit },
 318                { "merge", cmd_merge, RUN_SETUP | NEED_WORK_TREE },
 319                { "merge-base", cmd_merge_base, RUN_SETUP },
 320                { "merge-file", cmd_merge_file },
 321                { "merge-ours", cmd_merge_ours, RUN_SETUP },
 322                { "merge-recursive", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 323                { "merge-subtree", cmd_merge_recursive, RUN_SETUP | NEED_WORK_TREE },
 324                { "mv", cmd_mv, RUN_SETUP | NEED_WORK_TREE },
 325                { "name-rev", cmd_name_rev, RUN_SETUP },
 326                { "pack-objects", cmd_pack_objects, RUN_SETUP },
 327                { "peek-remote", cmd_ls_remote },
 328                { "pickaxe", cmd_blame, RUN_SETUP },
 329                { "prune", cmd_prune, RUN_SETUP },
 330                { "prune-packed", cmd_prune_packed, RUN_SETUP },
 331                { "push", cmd_push, RUN_SETUP },
 332                { "read-tree", cmd_read_tree, RUN_SETUP },
 333                { "receive-pack", cmd_receive_pack },
 334                { "reflog", cmd_reflog, RUN_SETUP },
 335                { "remote", cmd_remote, RUN_SETUP },
 336                { "repo-config", cmd_config },
 337                { "rerere", cmd_rerere, RUN_SETUP },
 338                { "reset", cmd_reset, RUN_SETUP },
 339                { "rev-list", cmd_rev_list, RUN_SETUP },
 340                { "rev-parse", cmd_rev_parse },
 341                { "revert", cmd_revert, RUN_SETUP | NEED_WORK_TREE },
 342                { "rm", cmd_rm, RUN_SETUP },
 343                { "send-pack", cmd_send_pack, RUN_SETUP },
 344                { "shortlog", cmd_shortlog, USE_PAGER },
 345                { "show-branch", cmd_show_branch, RUN_SETUP },
 346                { "show", cmd_show, RUN_SETUP | USE_PAGER },
 347                { "status", cmd_status, RUN_SETUP | NEED_WORK_TREE },
 348                { "stripspace", cmd_stripspace },
 349                { "symbolic-ref", cmd_symbolic_ref, RUN_SETUP },
 350                { "tag", cmd_tag, RUN_SETUP },
 351                { "tar-tree", cmd_tar_tree },
 352                { "unpack-objects", cmd_unpack_objects, RUN_SETUP },
 353                { "update-index", cmd_update_index, RUN_SETUP },
 354                { "update-ref", cmd_update_ref, RUN_SETUP },
 355                { "upload-archive", cmd_upload_archive },
 356                { "verify-tag", cmd_verify_tag, RUN_SETUP },
 357                { "version", cmd_version },
 358                { "whatchanged", cmd_whatchanged, RUN_SETUP | USE_PAGER },
 359                { "write-tree", cmd_write_tree, RUN_SETUP },
 360                { "verify-pack", cmd_verify_pack },
 361                { "show-ref", cmd_show_ref, RUN_SETUP },
 362                { "pack-refs", cmd_pack_refs, RUN_SETUP },
 363        };
 364        int i;
 365        static const char ext[] = STRIP_EXTENSION;
 366
 367        if (sizeof(ext) > 1) {
 368                i = strlen(argv[0]) - strlen(ext);
 369                if (i > 0 && !strcmp(argv[0] + i, ext)) {
 370                        char *argv0 = xstrdup(argv[0]);
 371                        argv[0] = cmd = argv0;
 372                        argv0[i] = '\0';
 373                }
 374        }
 375
 376        /* Turn "git cmd --help" into "git help cmd" */
 377        if (argc > 1 && !strcmp(argv[1], "--help")) {
 378                argv[1] = argv[0];
 379                argv[0] = cmd = "help";
 380        }
 381
 382        for (i = 0; i < ARRAY_SIZE(commands); i++) {
 383                struct cmd_struct *p = commands+i;
 384                if (strcmp(p->cmd, cmd))
 385                        continue;
 386                exit(run_command(p, argc, argv));
 387        }
 388}
 389
 390static void execv_dashed_external(const char **argv)
 391{
 392        struct strbuf cmd = STRBUF_INIT;
 393        const char *tmp;
 394
 395        strbuf_addf(&cmd, "git-%s", argv[0]);
 396
 397        /*
 398         * argv[0] must be the git command, but the argv array
 399         * belongs to the caller, and may be reused in
 400         * subsequent loop iterations. Save argv[0] and
 401         * restore it on error.
 402         */
 403        tmp = argv[0];
 404        argv[0] = cmd.buf;
 405
 406        trace_argv_printf(argv, "trace: exec:");
 407
 408        /* execvp() can only ever return if it fails */
 409        execvp(cmd.buf, (char **)argv);
 410
 411        trace_printf("trace: exec failed: %s\n", strerror(errno));
 412
 413        argv[0] = tmp;
 414
 415        strbuf_release(&cmd);
 416}
 417
 418
 419int main(int argc, const char **argv)
 420{
 421        const char *cmd = argv[0] && *argv[0] ? argv[0] : "git-help";
 422        char *slash = (char *)cmd + strlen(cmd);
 423        int done_alias = 0;
 424
 425        /*
 426         * Take the basename of argv[0] as the command
 427         * name, and the dirname as the default exec_path
 428         * if we don't have anything better.
 429         */
 430        do
 431                --slash;
 432        while (cmd <= slash && !is_dir_sep(*slash));
 433        if (cmd <= slash) {
 434                *slash++ = 0;
 435                git_set_argv0_path(cmd);
 436                cmd = slash;
 437        }
 438
 439        /*
 440         * "git-xxxx" is the same as "git xxxx", but we obviously:
 441         *
 442         *  - cannot take flags in between the "git" and the "xxxx".
 443         *  - cannot execute it externally (since it would just do
 444         *    the same thing over again)
 445         *
 446         * So we just directly call the internal command handler, and
 447         * die if that one cannot handle it.
 448         */
 449        if (!prefixcmp(cmd, "git-")) {
 450                cmd += 4;
 451                argv[0] = cmd;
 452                handle_internal_command(argc, argv);
 453                die("cannot handle %s internally", cmd);
 454        }
 455
 456        /* Look for flags.. */
 457        argv++;
 458        argc--;
 459        handle_options(&argv, &argc, NULL);
 460        commit_pager_choice();
 461        if (argc > 0) {
 462                if (!prefixcmp(argv[0], "--"))
 463                        argv[0] += 2;
 464        } else {
 465                /* The user didn't specify a command; give them help */
 466                printf("usage: %s\n\n", git_usage_string);
 467                list_common_cmds_help();
 468                printf("\n%s\n", git_more_info_string);
 469                exit(1);
 470        }
 471        cmd = argv[0];
 472
 473        /*
 474         * We use PATH to find git commands, but we prepend some higher
 475         * precidence paths: the "--exec-path" option, the GIT_EXEC_PATH
 476         * environment, and the $(gitexecdir) from the Makefile at build
 477         * time.
 478         */
 479        setup_path();
 480
 481        while (1) {
 482                /* See if it's an internal command */
 483                handle_internal_command(argc, argv);
 484
 485                /* .. then try the external ones */
 486                execv_dashed_external(argv);
 487
 488                /* It could be an alias -- this works around the insanity
 489                 * of overriding "git log" with "git show" by having
 490                 * alias.log = show
 491                 */
 492                if (done_alias || !handle_alias(&argc, &argv))
 493                        break;
 494                done_alias = 1;
 495        }
 496
 497        if (errno == ENOENT) {
 498                if (done_alias) {
 499                        fprintf(stderr, "Expansion of alias '%s' failed; "
 500                                "'%s' is not a git-command\n",
 501                                cmd, argv[0]);
 502                        exit(1);
 503                }
 504                argv[0] = help_unknown_cmd(cmd);
 505                handle_internal_command(argc, argv);
 506                execv_dashed_external(argv);
 507        }
 508
 509        fprintf(stderr, "Failed to run command '%s': %s\n",
 510                cmd, strerror(errno));
 511
 512        return 1;
 513}