Andrew's git / gitweb.git / builtin/cat-file.c
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builtin / cat-file.con commit Merge branch 'sb/string-list-remove-unused' into maint (d5e4cba)
   1/*
   2 * GIT - The information manager from hell
   3 *
   4 * Copyright (C) Linus Torvalds, 2005
   5 */
   6#include "cache.h"
   7#include "config.h"
   8#include "builtin.h"
   9#include "diff.h"
  10#include "parse-options.h"
  11#include "userdiff.h"
  12#include "streaming.h"
  13#include "tree-walk.h"
  14#include "sha1-array.h"
  15#include "packfile.h"
  16#include "object-store.h"
  17
  18struct batch_options {
  19        int enabled;
  20        int follow_symlinks;
  21        int print_contents;
  22        int buffer_output;
  23        int all_objects;
  24        int unordered;
  25        int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */
  26        const char *format;
  27};
  28
  29static const char *force_path;
  30
  31static int filter_object(const char *path, unsigned mode,
  32                         const struct object_id *oid,
  33                         char **buf, unsigned long *size)
  34{
  35        enum object_type type;
  36
  37        *buf = read_object_file(oid, &type, size);
  38        if (!*buf)
  39                return error(_("cannot read object %s '%s'"),
  40                             oid_to_hex(oid), path);
  41        if ((type == OBJ_BLOB) && S_ISREG(mode)) {
  42                struct strbuf strbuf = STRBUF_INIT;
  43                if (convert_to_working_tree(&the_index, path, *buf, *size, &strbuf)) {
  44                        free(*buf);
  45                        *size = strbuf.len;
  46                        *buf = strbuf_detach(&strbuf, NULL);
  47                }
  48        }
  49
  50        return 0;
  51}
  52
  53static int stream_blob(const struct object_id *oid)
  54{
  55        if (stream_blob_to_fd(1, oid, NULL, 0))
  56                die("unable to stream %s to stdout", oid_to_hex(oid));
  57        return 0;
  58}
  59
  60static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
  61                        int unknown_type)
  62{
  63        struct object_id oid;
  64        enum object_type type;
  65        char *buf;
  66        unsigned long size;
  67        struct object_context obj_context;
  68        struct object_info oi = OBJECT_INFO_INIT;
  69        struct strbuf sb = STRBUF_INIT;
  70        unsigned flags = OBJECT_INFO_LOOKUP_REPLACE;
  71        const char *path = force_path;
  72
  73        if (unknown_type)
  74                flags |= OBJECT_INFO_ALLOW_UNKNOWN_TYPE;
  75
  76        if (get_oid_with_context(obj_name, GET_OID_RECORD_PATH,
  77                                 &oid, &obj_context))
  78                die("Not a valid object name %s", obj_name);
  79
  80        if (!path)
  81                path = obj_context.path;
  82        if (obj_context.mode == S_IFINVALID)
  83                obj_context.mode = 0100644;
  84
  85        buf = NULL;
  86        switch (opt) {
  87        case 't':
  88                oi.type_name = &sb;
  89                if (oid_object_info_extended(the_repository, &oid, &oi, flags) < 0)
  90                        die("git cat-file: could not get object info");
  91                if (sb.len) {
  92                        printf("%s\n", sb.buf);
  93                        strbuf_release(&sb);
  94                        return 0;
  95                }
  96                break;
  97
  98        case 's':
  99                oi.sizep = &size;
 100                if (oid_object_info_extended(the_repository, &oid, &oi, flags) < 0)
 101                        die("git cat-file: could not get object info");
 102                printf("%lu\n", size);
 103                return 0;
 104
 105        case 'e':
 106                return !has_object_file(&oid);
 107
 108        case 'w':
 109                if (!path)
 110                        die("git cat-file --filters %s: <object> must be "
 111                            "<sha1:path>", obj_name);
 112
 113                if (filter_object(path, obj_context.mode,
 114                                  &oid, &buf, &size))
 115                        return -1;
 116                break;
 117
 118        case 'c':
 119                if (!path)
 120                        die("git cat-file --textconv %s: <object> must be <sha1:path>",
 121                            obj_name);
 122
 123                if (textconv_object(path, obj_context.mode, &oid, 1, &buf, &size))
 124                        break;
 125                /* else fallthrough */
 126
 127        case 'p':
 128                type = oid_object_info(the_repository, &oid, NULL);
 129                if (type < 0)
 130                        die("Not a valid object name %s", obj_name);
 131
 132                /* custom pretty-print here */
 133                if (type == OBJ_TREE) {
 134                        const char *ls_args[3] = { NULL };
 135                        ls_args[0] =  "ls-tree";
 136                        ls_args[1] =  obj_name;
 137                        return cmd_ls_tree(2, ls_args, NULL);
 138                }
 139
 140                if (type == OBJ_BLOB)
 141                        return stream_blob(&oid);
 142                buf = read_object_file(&oid, &type, &size);
 143                if (!buf)
 144                        die("Cannot read object %s", obj_name);
 145
 146                /* otherwise just spit out the data */
 147                break;
 148
 149        case 0:
 150                if (type_from_string(exp_type) == OBJ_BLOB) {
 151                        struct object_id blob_oid;
 152                        if (oid_object_info(the_repository, &oid, NULL) == OBJ_TAG) {
 153                                char *buffer = read_object_file(&oid, &type,
 154                                                                &size);
 155                                const char *target;
 156                                if (!skip_prefix(buffer, "object ", &target) ||
 157                                    get_oid_hex(target, &blob_oid))
 158                                        die("%s not a valid tag", oid_to_hex(&oid));
 159                                free(buffer);
 160                        } else
 161                                oidcpy(&blob_oid, &oid);
 162
 163                        if (oid_object_info(the_repository, &blob_oid, NULL) == OBJ_BLOB)
 164                                return stream_blob(&blob_oid);
 165                        /*
 166                         * we attempted to dereference a tag to a blob
 167                         * and failed; there may be new dereference
 168                         * mechanisms this code is not aware of.
 169                         * fall-back to the usual case.
 170                         */
 171                }
 172                buf = read_object_with_reference(&oid, exp_type, &size, NULL);
 173                break;
 174
 175        default:
 176                die("git cat-file: unknown option: %s", exp_type);
 177        }
 178
 179        if (!buf)
 180                die("git cat-file %s: bad file", obj_name);
 181
 182        write_or_die(1, buf, size);
 183        free(buf);
 184        free(obj_context.path);
 185        return 0;
 186}
 187
 188struct expand_data {
 189        struct object_id oid;
 190        enum object_type type;
 191        unsigned long size;
 192        off_t disk_size;
 193        const char *rest;
 194        struct object_id delta_base_oid;
 195
 196        /*
 197         * If mark_query is true, we do not expand anything, but rather
 198         * just mark the object_info with items we wish to query.
 199         */
 200        int mark_query;
 201
 202        /*
 203         * Whether to split the input on whitespace before feeding it to
 204         * get_sha1; this is decided during the mark_query phase based on
 205         * whether we have a %(rest) token in our format.
 206         */
 207        int split_on_whitespace;
 208
 209        /*
 210         * After a mark_query run, this object_info is set up to be
 211         * passed to sha1_object_info_extended. It will point to the data
 212         * elements above, so you can retrieve the response from there.
 213         */
 214        struct object_info info;
 215
 216        /*
 217         * This flag will be true if the requested batch format and options
 218         * don't require us to call sha1_object_info, which can then be
 219         * optimized out.
 220         */
 221        unsigned skip_object_info : 1;
 222};
 223
 224static int is_atom(const char *atom, const char *s, int slen)
 225{
 226        int alen = strlen(atom);
 227        return alen == slen && !memcmp(atom, s, alen);
 228}
 229
 230static void expand_atom(struct strbuf *sb, const char *atom, int len,
 231                        void *vdata)
 232{
 233        struct expand_data *data = vdata;
 234
 235        if (is_atom("objectname", atom, len)) {
 236                if (!data->mark_query)
 237                        strbuf_addstr(sb, oid_to_hex(&data->oid));
 238        } else if (is_atom("objecttype", atom, len)) {
 239                if (data->mark_query)
 240                        data->info.typep = &data->type;
 241                else
 242                        strbuf_addstr(sb, type_name(data->type));
 243        } else if (is_atom("objectsize", atom, len)) {
 244                if (data->mark_query)
 245                        data->info.sizep = &data->size;
 246                else
 247                        strbuf_addf(sb, "%lu", data->size);
 248        } else if (is_atom("objectsize:disk", atom, len)) {
 249                if (data->mark_query)
 250                        data->info.disk_sizep = &data->disk_size;
 251                else
 252                        strbuf_addf(sb, "%"PRIuMAX, (uintmax_t)data->disk_size);
 253        } else if (is_atom("rest", atom, len)) {
 254                if (data->mark_query)
 255                        data->split_on_whitespace = 1;
 256                else if (data->rest)
 257                        strbuf_addstr(sb, data->rest);
 258        } else if (is_atom("deltabase", atom, len)) {
 259                if (data->mark_query)
 260                        data->info.delta_base_sha1 = data->delta_base_oid.hash;
 261                else
 262                        strbuf_addstr(sb,
 263                                      oid_to_hex(&data->delta_base_oid));
 264        } else
 265                die("unknown format element: %.*s", len, atom);
 266}
 267
 268static size_t expand_format(struct strbuf *sb, const char *start, void *data)
 269{
 270        const char *end;
 271
 272        if (*start != '(')
 273                return 0;
 274        end = strchr(start + 1, ')');
 275        if (!end)
 276                die("format element '%s' does not end in ')'", start);
 277
 278        expand_atom(sb, start + 1, end - start - 1, data);
 279
 280        return end - start + 1;
 281}
 282
 283static void batch_write(struct batch_options *opt, const void *data, int len)
 284{
 285        if (opt->buffer_output) {
 286                if (fwrite(data, 1, len, stdout) != len)
 287                        die_errno("unable to write to stdout");
 288        } else
 289                write_or_die(1, data, len);
 290}
 291
 292static void print_object_or_die(struct batch_options *opt, struct expand_data *data)
 293{
 294        const struct object_id *oid = &data->oid;
 295
 296        assert(data->info.typep);
 297
 298        if (data->type == OBJ_BLOB) {
 299                if (opt->buffer_output)
 300                        fflush(stdout);
 301                if (opt->cmdmode) {
 302                        char *contents;
 303                        unsigned long size;
 304
 305                        if (!data->rest)
 306                                die("missing path for '%s'", oid_to_hex(oid));
 307
 308                        if (opt->cmdmode == 'w') {
 309                                if (filter_object(data->rest, 0100644, oid,
 310                                                  &contents, &size))
 311                                        die("could not convert '%s' %s",
 312                                            oid_to_hex(oid), data->rest);
 313                        } else if (opt->cmdmode == 'c') {
 314                                enum object_type type;
 315                                if (!textconv_object(data->rest, 0100644, oid,
 316                                                     1, &contents, &size))
 317                                        contents = read_object_file(oid,
 318                                                                    &type,
 319                                                                    &size);
 320                                if (!contents)
 321                                        die("could not convert '%s' %s",
 322                                            oid_to_hex(oid), data->rest);
 323                        } else
 324                                BUG("invalid cmdmode: %c", opt->cmdmode);
 325                        batch_write(opt, contents, size);
 326                        free(contents);
 327                } else {
 328                        stream_blob(oid);
 329                }
 330        }
 331        else {
 332                enum object_type type;
 333                unsigned long size;
 334                void *contents;
 335
 336                contents = read_object_file(oid, &type, &size);
 337                if (!contents)
 338                        die("object %s disappeared", oid_to_hex(oid));
 339                if (type != data->type)
 340                        die("object %s changed type!?", oid_to_hex(oid));
 341                if (data->info.sizep && size != data->size)
 342                        die("object %s changed size!?", oid_to_hex(oid));
 343
 344                batch_write(opt, contents, size);
 345                free(contents);
 346        }
 347}
 348
 349static void batch_object_write(const char *obj_name,
 350                               struct strbuf *scratch,
 351                               struct batch_options *opt,
 352                               struct expand_data *data)
 353{
 354        if (!data->skip_object_info &&
 355            oid_object_info_extended(the_repository, &data->oid, &data->info,
 356                                     OBJECT_INFO_LOOKUP_REPLACE) < 0) {
 357                printf("%s missing\n",
 358                       obj_name ? obj_name : oid_to_hex(&data->oid));
 359                fflush(stdout);
 360                return;
 361        }
 362
 363        strbuf_reset(scratch);
 364        strbuf_expand(scratch, opt->format, expand_format, data);
 365        strbuf_addch(scratch, '\n');
 366        batch_write(opt, scratch->buf, scratch->len);
 367
 368        if (opt->print_contents) {
 369                print_object_or_die(opt, data);
 370                batch_write(opt, "\n", 1);
 371        }
 372}
 373
 374static void batch_one_object(const char *obj_name,
 375                             struct strbuf *scratch,
 376                             struct batch_options *opt,
 377                             struct expand_data *data)
 378{
 379        struct object_context ctx;
 380        int flags = opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0;
 381        enum follow_symlinks_result result;
 382
 383        result = get_oid_with_context(obj_name, flags, &data->oid, &ctx);
 384        if (result != FOUND) {
 385                switch (result) {
 386                case MISSING_OBJECT:
 387                        printf("%s missing\n", obj_name);
 388                        break;
 389                case DANGLING_SYMLINK:
 390                        printf("dangling %"PRIuMAX"\n%s\n",
 391                               (uintmax_t)strlen(obj_name), obj_name);
 392                        break;
 393                case SYMLINK_LOOP:
 394                        printf("loop %"PRIuMAX"\n%s\n",
 395                               (uintmax_t)strlen(obj_name), obj_name);
 396                        break;
 397                case NOT_DIR:
 398                        printf("notdir %"PRIuMAX"\n%s\n",
 399                               (uintmax_t)strlen(obj_name), obj_name);
 400                        break;
 401                default:
 402                        BUG("unknown get_sha1_with_context result %d\n",
 403                               result);
 404                        break;
 405                }
 406                fflush(stdout);
 407                return;
 408        }
 409
 410        if (ctx.mode == 0) {
 411                printf("symlink %"PRIuMAX"\n%s\n",
 412                       (uintmax_t)ctx.symlink_path.len,
 413                       ctx.symlink_path.buf);
 414                fflush(stdout);
 415                return;
 416        }
 417
 418        batch_object_write(obj_name, scratch, opt, data);
 419}
 420
 421struct object_cb_data {
 422        struct batch_options *opt;
 423        struct expand_data *expand;
 424        struct oidset *seen;
 425        struct strbuf *scratch;
 426};
 427
 428static int batch_object_cb(const struct object_id *oid, void *vdata)
 429{
 430        struct object_cb_data *data = vdata;
 431        oidcpy(&data->expand->oid, oid);
 432        batch_object_write(NULL, data->scratch, data->opt, data->expand);
 433        return 0;
 434}
 435
 436static int collect_loose_object(const struct object_id *oid,
 437                                const char *path,
 438                                void *data)
 439{
 440        oid_array_append(data, oid);
 441        return 0;
 442}
 443
 444static int collect_packed_object(const struct object_id *oid,
 445                                 struct packed_git *pack,
 446                                 uint32_t pos,
 447                                 void *data)
 448{
 449        oid_array_append(data, oid);
 450        return 0;
 451}
 452
 453static int batch_unordered_object(const struct object_id *oid, void *vdata)
 454{
 455        struct object_cb_data *data = vdata;
 456
 457        if (oidset_insert(data->seen, oid))
 458                return 0;
 459
 460        return batch_object_cb(oid, data);
 461}
 462
 463static int batch_unordered_loose(const struct object_id *oid,
 464                                 const char *path,
 465                                 void *data)
 466{
 467        return batch_unordered_object(oid, data);
 468}
 469
 470static int batch_unordered_packed(const struct object_id *oid,
 471                                  struct packed_git *pack,
 472                                  uint32_t pos,
 473                                  void *data)
 474{
 475        return batch_unordered_object(oid, data);
 476}
 477
 478static int batch_objects(struct batch_options *opt)
 479{
 480        struct strbuf input = STRBUF_INIT;
 481        struct strbuf output = STRBUF_INIT;
 482        struct expand_data data;
 483        int save_warning;
 484        int retval = 0;
 485
 486        if (!opt->format)
 487                opt->format = "%(objectname) %(objecttype) %(objectsize)";
 488
 489        /*
 490         * Expand once with our special mark_query flag, which will prime the
 491         * object_info to be handed to sha1_object_info_extended for each
 492         * object.
 493         */
 494        memset(&data, 0, sizeof(data));
 495        data.mark_query = 1;
 496        strbuf_expand(&output, opt->format, expand_format, &data);
 497        data.mark_query = 0;
 498        strbuf_release(&output);
 499        if (opt->cmdmode)
 500                data.split_on_whitespace = 1;
 501
 502        if (opt->all_objects) {
 503                struct object_info empty = OBJECT_INFO_INIT;
 504                if (!memcmp(&data.info, &empty, sizeof(empty)))
 505                        data.skip_object_info = 1;
 506        }
 507
 508        /*
 509         * If we are printing out the object, then always fill in the type,
 510         * since we will want to decide whether or not to stream.
 511         */
 512        if (opt->print_contents)
 513                data.info.typep = &data.type;
 514
 515        if (opt->all_objects) {
 516                struct object_cb_data cb;
 517
 518                if (repository_format_partial_clone)
 519                        warning("This repository has extensions.partialClone set. Some objects may not be loaded.");
 520
 521                cb.opt = opt;
 522                cb.expand = &data;
 523                cb.scratch = &output;
 524
 525                if (opt->unordered) {
 526                        struct oidset seen = OIDSET_INIT;
 527
 528                        cb.seen = &seen;
 529
 530                        for_each_loose_object(batch_unordered_loose, &cb, 0);
 531                        for_each_packed_object(batch_unordered_packed, &cb,
 532                                               FOR_EACH_OBJECT_PACK_ORDER);
 533
 534                        oidset_clear(&seen);
 535                } else {
 536                        struct oid_array sa = OID_ARRAY_INIT;
 537
 538                        for_each_loose_object(collect_loose_object, &sa, 0);
 539                        for_each_packed_object(collect_packed_object, &sa, 0);
 540
 541                        oid_array_for_each_unique(&sa, batch_object_cb, &cb);
 542
 543                        oid_array_clear(&sa);
 544                }
 545
 546                strbuf_release(&output);
 547                return 0;
 548        }
 549
 550        /*
 551         * We are going to call get_sha1 on a potentially very large number of
 552         * objects. In most large cases, these will be actual object sha1s. The
 553         * cost to double-check that each one is not also a ref (just so we can
 554         * warn) ends up dwarfing the actual cost of the object lookups
 555         * themselves. We can work around it by just turning off the warning.
 556         */
 557        save_warning = warn_on_object_refname_ambiguity;
 558        warn_on_object_refname_ambiguity = 0;
 559
 560        while (strbuf_getline(&input, stdin) != EOF) {
 561                if (data.split_on_whitespace) {
 562                        /*
 563                         * Split at first whitespace, tying off the beginning
 564                         * of the string and saving the remainder (or NULL) in
 565                         * data.rest.
 566                         */
 567                        char *p = strpbrk(input.buf, " \t");
 568                        if (p) {
 569                                while (*p && strchr(" \t", *p))
 570                                        *p++ = '\0';
 571                        }
 572                        data.rest = p;
 573                }
 574
 575                batch_one_object(input.buf, &output, opt, &data);
 576        }
 577
 578        strbuf_release(&input);
 579        strbuf_release(&output);
 580        warn_on_object_refname_ambiguity = save_warning;
 581        return retval;
 582}
 583
 584static const char * const cat_file_usage[] = {
 585        N_("git cat-file (-t [--allow-unknown-type] | -s [--allow-unknown-type] | -e | -p | <type> | --textconv | --filters) [--path=<path>] <object>"),
 586        N_("git cat-file (--batch | --batch-check) [--follow-symlinks] [--textconv | --filters]"),
 587        NULL
 588};
 589
 590static int git_cat_file_config(const char *var, const char *value, void *cb)
 591{
 592        if (userdiff_config(var, value) < 0)
 593                return -1;
 594
 595        return git_default_config(var, value, cb);
 596}
 597
 598static int batch_option_callback(const struct option *opt,
 599                                 const char *arg,
 600                                 int unset)
 601{
 602        struct batch_options *bo = opt->value;
 603
 604        if (bo->enabled) {
 605                return 1;
 606        }
 607
 608        bo->enabled = 1;
 609        bo->print_contents = !strcmp(opt->long_name, "batch");
 610        bo->format = arg;
 611
 612        return 0;
 613}
 614
 615int cmd_cat_file(int argc, const char **argv, const char *prefix)
 616{
 617        int opt = 0;
 618        const char *exp_type = NULL, *obj_name = NULL;
 619        struct batch_options batch = {0};
 620        int unknown_type = 0;
 621
 622        const struct option options[] = {
 623                OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
 624                OPT_CMDMODE('t', NULL, &opt, N_("show object type"), 't'),
 625                OPT_CMDMODE('s', NULL, &opt, N_("show object size"), 's'),
 626                OPT_CMDMODE('e', NULL, &opt,
 627                            N_("exit with zero when there's no error"), 'e'),
 628                OPT_CMDMODE('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
 629                OPT_CMDMODE(0, "textconv", &opt,
 630                            N_("for blob objects, run textconv on object's content"), 'c'),
 631                OPT_CMDMODE(0, "filters", &opt,
 632                            N_("for blob objects, run filters on object's content"), 'w'),
 633                OPT_STRING(0, "path", &force_path, N_("blob"),
 634                           N_("use a specific path for --textconv/--filters")),
 635                OPT_BOOL(0, "allow-unknown-type", &unknown_type,
 636                          N_("allow -s and -t to work with broken/corrupt objects")),
 637                OPT_BOOL(0, "buffer", &batch.buffer_output, N_("buffer --batch output")),
 638                { OPTION_CALLBACK, 0, "batch", &batch, "format",
 639                        N_("show info and content of objects fed from the standard input"),
 640                        PARSE_OPT_OPTARG, batch_option_callback },
 641                { OPTION_CALLBACK, 0, "batch-check", &batch, "format",
 642                        N_("show info about objects fed from the standard input"),
 643                        PARSE_OPT_OPTARG, batch_option_callback },
 644                OPT_BOOL(0, "follow-symlinks", &batch.follow_symlinks,
 645                         N_("follow in-tree symlinks (used with --batch or --batch-check)")),
 646                OPT_BOOL(0, "batch-all-objects", &batch.all_objects,
 647                         N_("show all objects with --batch or --batch-check")),
 648                OPT_BOOL(0, "unordered", &batch.unordered,
 649                         N_("do not order --batch-all-objects output")),
 650                OPT_END()
 651        };
 652
 653        git_config(git_cat_file_config, NULL);
 654
 655        batch.buffer_output = -1;
 656        argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 657
 658        if (opt) {
 659                if (batch.enabled && (opt == 'c' || opt == 'w'))
 660                        batch.cmdmode = opt;
 661                else if (argc == 1)
 662                        obj_name = argv[0];
 663                else
 664                        usage_with_options(cat_file_usage, options);
 665        }
 666        if (!opt && !batch.enabled) {
 667                if (argc == 2) {
 668                        exp_type = argv[0];
 669                        obj_name = argv[1];
 670                } else
 671                        usage_with_options(cat_file_usage, options);
 672        }
 673        if (batch.enabled) {
 674                if (batch.cmdmode != opt || argc)
 675                        usage_with_options(cat_file_usage, options);
 676                if (batch.cmdmode && batch.all_objects)
 677                        die("--batch-all-objects cannot be combined with "
 678                            "--textconv nor with --filters");
 679        }
 680
 681        if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
 682                usage_with_options(cat_file_usage, options);
 683        }
 684
 685        if (force_path && opt != 'c' && opt != 'w') {
 686                error("--path=<path> needs --textconv or --filters");
 687                usage_with_options(cat_file_usage, options);
 688        }
 689
 690        if (force_path && batch.enabled) {
 691                error("--path=<path> incompatible with --batch");
 692                usage_with_options(cat_file_usage, options);
 693        }
 694
 695        if (batch.buffer_output < 0)
 696                batch.buffer_output = batch.all_objects;
 697
 698        if (batch.enabled)
 699                return batch_objects(&batch);
 700
 701        if (unknown_type && opt != 't' && opt != 's')
 702                die("git cat-file --allow-unknown-type: use with -s or -t");
 703        return cat_one_file(opt, exp_type, obj_name, unknown_type);
 704}