builtin / cat-file.con commit Merge branch 'jk/tempfile-ferror-fclose-confusion' (c5b22b8)
   1/*
   2 * GIT - The information manager from hell
   3 *
   4 * Copyright (C) Linus Torvalds, 2005
   5 */
   6#include "cache.h"
   7#include "builtin.h"
   8#include "parse-options.h"
   9#include "userdiff.h"
  10#include "streaming.h"
  11#include "tree-walk.h"
  12#include "sha1-array.h"
  13
  14struct batch_options {
  15        int enabled;
  16        int follow_symlinks;
  17        int print_contents;
  18        int buffer_output;
  19        int all_objects;
  20        int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */
  21        const char *format;
  22};
  23
  24static const char *force_path;
  25
  26static int filter_object(const char *path, unsigned mode,
  27                         const struct object_id *oid,
  28                         char **buf, unsigned long *size)
  29{
  30        enum object_type type;
  31
  32        *buf = read_sha1_file(oid->hash, &type, size);
  33        if (!*buf)
  34                return error(_("cannot read object %s '%s'"),
  35                             oid_to_hex(oid), path);
  36        if ((type == OBJ_BLOB) && S_ISREG(mode)) {
  37                struct strbuf strbuf = STRBUF_INIT;
  38                if (convert_to_working_tree(path, *buf, *size, &strbuf)) {
  39                        free(*buf);
  40                        *size = strbuf.len;
  41                        *buf = strbuf_detach(&strbuf, NULL);
  42                }
  43        }
  44
  45        return 0;
  46}
  47
  48static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
  49                        int unknown_type)
  50{
  51        struct object_id oid;
  52        enum object_type type;
  53        char *buf;
  54        unsigned long size;
  55        struct object_context obj_context;
  56        struct object_info oi = OBJECT_INFO_INIT;
  57        struct strbuf sb = STRBUF_INIT;
  58        unsigned flags = LOOKUP_REPLACE_OBJECT;
  59        const char *path = force_path;
  60
  61        if (unknown_type)
  62                flags |= LOOKUP_UNKNOWN_OBJECT;
  63
  64        if (get_sha1_with_context(obj_name, 0, oid.hash, &obj_context))
  65                die("Not a valid object name %s", obj_name);
  66
  67        if (!path)
  68                path = obj_context.path;
  69        if (obj_context.mode == S_IFINVALID)
  70                obj_context.mode = 0100644;
  71
  72        buf = NULL;
  73        switch (opt) {
  74        case 't':
  75                oi.typename = &sb;
  76                if (sha1_object_info_extended(oid.hash, &oi, flags) < 0)
  77                        die("git cat-file: could not get object info");
  78                if (sb.len) {
  79                        printf("%s\n", sb.buf);
  80                        strbuf_release(&sb);
  81                        return 0;
  82                }
  83                break;
  84
  85        case 's':
  86                oi.sizep = &size;
  87                if (sha1_object_info_extended(oid.hash, &oi, flags) < 0)
  88                        die("git cat-file: could not get object info");
  89                printf("%lu\n", size);
  90                return 0;
  91
  92        case 'e':
  93                return !has_object_file(&oid);
  94
  95        case 'w':
  96                if (!path[0])
  97                        die("git cat-file --filters %s: <object> must be "
  98                            "<sha1:path>", obj_name);
  99
 100                if (filter_object(path, obj_context.mode,
 101                                  &oid, &buf, &size))
 102                        return -1;
 103                break;
 104
 105        case 'c':
 106                if (!path[0])
 107                        die("git cat-file --textconv %s: <object> must be <sha1:path>",
 108                            obj_name);
 109
 110                if (textconv_object(path, obj_context.mode, &oid, 1, &buf, &size))
 111                        break;
 112
 113        case 'p':
 114                type = sha1_object_info(oid.hash, NULL);
 115                if (type < 0)
 116                        die("Not a valid object name %s", obj_name);
 117
 118                /* custom pretty-print here */
 119                if (type == OBJ_TREE) {
 120                        const char *ls_args[3] = { NULL };
 121                        ls_args[0] =  "ls-tree";
 122                        ls_args[1] =  obj_name;
 123                        return cmd_ls_tree(2, ls_args, NULL);
 124                }
 125
 126                if (type == OBJ_BLOB)
 127                        return stream_blob_to_fd(1, &oid, NULL, 0);
 128                buf = read_sha1_file(oid.hash, &type, &size);
 129                if (!buf)
 130                        die("Cannot read object %s", obj_name);
 131
 132                /* otherwise just spit out the data */
 133                break;
 134
 135        case 0:
 136                if (type_from_string(exp_type) == OBJ_BLOB) {
 137                        struct object_id blob_oid;
 138                        if (sha1_object_info(oid.hash, NULL) == OBJ_TAG) {
 139                                char *buffer = read_sha1_file(oid.hash, &type, &size);
 140                                const char *target;
 141                                if (!skip_prefix(buffer, "object ", &target) ||
 142                                    get_oid_hex(target, &blob_oid))
 143                                        die("%s not a valid tag", oid_to_hex(&oid));
 144                                free(buffer);
 145                        } else
 146                                oidcpy(&blob_oid, &oid);
 147
 148                        if (sha1_object_info(blob_oid.hash, NULL) == OBJ_BLOB)
 149                                return stream_blob_to_fd(1, &blob_oid, NULL, 0);
 150                        /*
 151                         * we attempted to dereference a tag to a blob
 152                         * and failed; there may be new dereference
 153                         * mechanisms this code is not aware of.
 154                         * fall-back to the usual case.
 155                         */
 156                }
 157                buf = read_object_with_reference(oid.hash, exp_type, &size, NULL);
 158                break;
 159
 160        default:
 161                die("git cat-file: unknown option: %s", exp_type);
 162        }
 163
 164        if (!buf)
 165                die("git cat-file %s: bad file", obj_name);
 166
 167        write_or_die(1, buf, size);
 168        return 0;
 169}
 170
 171struct expand_data {
 172        struct object_id oid;
 173        enum object_type type;
 174        unsigned long size;
 175        off_t disk_size;
 176        const char *rest;
 177        struct object_id delta_base_oid;
 178
 179        /*
 180         * If mark_query is true, we do not expand anything, but rather
 181         * just mark the object_info with items we wish to query.
 182         */
 183        int mark_query;
 184
 185        /*
 186         * Whether to split the input on whitespace before feeding it to
 187         * get_sha1; this is decided during the mark_query phase based on
 188         * whether we have a %(rest) token in our format.
 189         */
 190        int split_on_whitespace;
 191
 192        /*
 193         * After a mark_query run, this object_info is set up to be
 194         * passed to sha1_object_info_extended. It will point to the data
 195         * elements above, so you can retrieve the response from there.
 196         */
 197        struct object_info info;
 198
 199        /*
 200         * This flag will be true if the requested batch format and options
 201         * don't require us to call sha1_object_info, which can then be
 202         * optimized out.
 203         */
 204        unsigned skip_object_info : 1;
 205};
 206
 207static int is_atom(const char *atom, const char *s, int slen)
 208{
 209        int alen = strlen(atom);
 210        return alen == slen && !memcmp(atom, s, alen);
 211}
 212
 213static void expand_atom(struct strbuf *sb, const char *atom, int len,
 214                        void *vdata)
 215{
 216        struct expand_data *data = vdata;
 217
 218        if (is_atom("objectname", atom, len)) {
 219                if (!data->mark_query)
 220                        strbuf_addstr(sb, oid_to_hex(&data->oid));
 221        } else if (is_atom("objecttype", atom, len)) {
 222                if (data->mark_query)
 223                        data->info.typep = &data->type;
 224                else
 225                        strbuf_addstr(sb, typename(data->type));
 226        } else if (is_atom("objectsize", atom, len)) {
 227                if (data->mark_query)
 228                        data->info.sizep = &data->size;
 229                else
 230                        strbuf_addf(sb, "%lu", data->size);
 231        } else if (is_atom("objectsize:disk", atom, len)) {
 232                if (data->mark_query)
 233                        data->info.disk_sizep = &data->disk_size;
 234                else
 235                        strbuf_addf(sb, "%"PRIuMAX, (uintmax_t)data->disk_size);
 236        } else if (is_atom("rest", atom, len)) {
 237                if (data->mark_query)
 238                        data->split_on_whitespace = 1;
 239                else if (data->rest)
 240                        strbuf_addstr(sb, data->rest);
 241        } else if (is_atom("deltabase", atom, len)) {
 242                if (data->mark_query)
 243                        data->info.delta_base_sha1 = data->delta_base_oid.hash;
 244                else
 245                        strbuf_addstr(sb,
 246                                      oid_to_hex(&data->delta_base_oid));
 247        } else
 248                die("unknown format element: %.*s", len, atom);
 249}
 250
 251static size_t expand_format(struct strbuf *sb, const char *start, void *data)
 252{
 253        const char *end;
 254
 255        if (*start != '(')
 256                return 0;
 257        end = strchr(start + 1, ')');
 258        if (!end)
 259                die("format element '%s' does not end in ')'", start);
 260
 261        expand_atom(sb, start + 1, end - start - 1, data);
 262
 263        return end - start + 1;
 264}
 265
 266static void batch_write(struct batch_options *opt, const void *data, int len)
 267{
 268        if (opt->buffer_output) {
 269                if (fwrite(data, 1, len, stdout) != len)
 270                        die_errno("unable to write to stdout");
 271        } else
 272                write_or_die(1, data, len);
 273}
 274
 275static void print_object_or_die(struct batch_options *opt, struct expand_data *data)
 276{
 277        const struct object_id *oid = &data->oid;
 278
 279        assert(data->info.typep);
 280
 281        if (data->type == OBJ_BLOB) {
 282                if (opt->buffer_output)
 283                        fflush(stdout);
 284                if (opt->cmdmode) {
 285                        char *contents;
 286                        unsigned long size;
 287
 288                        if (!data->rest)
 289                                die("missing path for '%s'", oid_to_hex(oid));
 290
 291                        if (opt->cmdmode == 'w') {
 292                                if (filter_object(data->rest, 0100644, oid,
 293                                                  &contents, &size))
 294                                        die("could not convert '%s' %s",
 295                                            oid_to_hex(oid), data->rest);
 296                        } else if (opt->cmdmode == 'c') {
 297                                enum object_type type;
 298                                if (!textconv_object(data->rest, 0100644, oid,
 299                                                     1, &contents, &size))
 300                                        contents = read_sha1_file(oid->hash, &type,
 301                                                                  &size);
 302                                if (!contents)
 303                                        die("could not convert '%s' %s",
 304                                            oid_to_hex(oid), data->rest);
 305                        } else
 306                                die("BUG: invalid cmdmode: %c", opt->cmdmode);
 307                        batch_write(opt, contents, size);
 308                        free(contents);
 309                } else if (stream_blob_to_fd(1, oid, NULL, 0) < 0)
 310                        die("unable to stream %s to stdout", oid_to_hex(oid));
 311        }
 312        else {
 313                enum object_type type;
 314                unsigned long size;
 315                void *contents;
 316
 317                contents = read_sha1_file(oid->hash, &type, &size);
 318                if (!contents)
 319                        die("object %s disappeared", oid_to_hex(oid));
 320                if (type != data->type)
 321                        die("object %s changed type!?", oid_to_hex(oid));
 322                if (data->info.sizep && size != data->size)
 323                        die("object %s changed size!?", oid_to_hex(oid));
 324
 325                batch_write(opt, contents, size);
 326                free(contents);
 327        }
 328}
 329
 330static void batch_object_write(const char *obj_name, struct batch_options *opt,
 331                               struct expand_data *data)
 332{
 333        struct strbuf buf = STRBUF_INIT;
 334
 335        if (!data->skip_object_info &&
 336            sha1_object_info_extended(data->oid.hash, &data->info, LOOKUP_REPLACE_OBJECT) < 0) {
 337                printf("%s missing\n",
 338                       obj_name ? obj_name : oid_to_hex(&data->oid));
 339                fflush(stdout);
 340                return;
 341        }
 342
 343        strbuf_expand(&buf, opt->format, expand_format, data);
 344        strbuf_addch(&buf, '\n');
 345        batch_write(opt, buf.buf, buf.len);
 346        strbuf_release(&buf);
 347
 348        if (opt->print_contents) {
 349                print_object_or_die(opt, data);
 350                batch_write(opt, "\n", 1);
 351        }
 352}
 353
 354static void batch_one_object(const char *obj_name, struct batch_options *opt,
 355                             struct expand_data *data)
 356{
 357        struct object_context ctx;
 358        int flags = opt->follow_symlinks ? GET_SHA1_FOLLOW_SYMLINKS : 0;
 359        enum follow_symlinks_result result;
 360
 361        result = get_sha1_with_context(obj_name, flags, data->oid.hash, &ctx);
 362        if (result != FOUND) {
 363                switch (result) {
 364                case MISSING_OBJECT:
 365                        printf("%s missing\n", obj_name);
 366                        break;
 367                case DANGLING_SYMLINK:
 368                        printf("dangling %"PRIuMAX"\n%s\n",
 369                               (uintmax_t)strlen(obj_name), obj_name);
 370                        break;
 371                case SYMLINK_LOOP:
 372                        printf("loop %"PRIuMAX"\n%s\n",
 373                               (uintmax_t)strlen(obj_name), obj_name);
 374                        break;
 375                case NOT_DIR:
 376                        printf("notdir %"PRIuMAX"\n%s\n",
 377                               (uintmax_t)strlen(obj_name), obj_name);
 378                        break;
 379                default:
 380                        die("BUG: unknown get_sha1_with_context result %d\n",
 381                               result);
 382                        break;
 383                }
 384                fflush(stdout);
 385                return;
 386        }
 387
 388        if (ctx.mode == 0) {
 389                printf("symlink %"PRIuMAX"\n%s\n",
 390                       (uintmax_t)ctx.symlink_path.len,
 391                       ctx.symlink_path.buf);
 392                fflush(stdout);
 393                return;
 394        }
 395
 396        batch_object_write(obj_name, opt, data);
 397}
 398
 399struct object_cb_data {
 400        struct batch_options *opt;
 401        struct expand_data *expand;
 402};
 403
 404static int batch_object_cb(const unsigned char sha1[20], void *vdata)
 405{
 406        struct object_cb_data *data = vdata;
 407        hashcpy(data->expand->oid.hash, sha1);
 408        batch_object_write(NULL, data->opt, data->expand);
 409        return 0;
 410}
 411
 412static int batch_loose_object(const unsigned char *sha1,
 413                              const char *path,
 414                              void *data)
 415{
 416        sha1_array_append(data, sha1);
 417        return 0;
 418}
 419
 420static int batch_packed_object(const unsigned char *sha1,
 421                               struct packed_git *pack,
 422                               uint32_t pos,
 423                               void *data)
 424{
 425        sha1_array_append(data, sha1);
 426        return 0;
 427}
 428
 429static int batch_objects(struct batch_options *opt)
 430{
 431        struct strbuf buf = STRBUF_INIT;
 432        struct expand_data data;
 433        int save_warning;
 434        int retval = 0;
 435
 436        if (!opt->format)
 437                opt->format = "%(objectname) %(objecttype) %(objectsize)";
 438
 439        /*
 440         * Expand once with our special mark_query flag, which will prime the
 441         * object_info to be handed to sha1_object_info_extended for each
 442         * object.
 443         */
 444        memset(&data, 0, sizeof(data));
 445        data.mark_query = 1;
 446        strbuf_expand(&buf, opt->format, expand_format, &data);
 447        data.mark_query = 0;
 448        if (opt->cmdmode)
 449                data.split_on_whitespace = 1;
 450
 451        if (opt->all_objects) {
 452                struct object_info empty = OBJECT_INFO_INIT;
 453                if (!memcmp(&data.info, &empty, sizeof(empty)))
 454                        data.skip_object_info = 1;
 455        }
 456
 457        /*
 458         * If we are printing out the object, then always fill in the type,
 459         * since we will want to decide whether or not to stream.
 460         */
 461        if (opt->print_contents)
 462                data.info.typep = &data.type;
 463
 464        if (opt->all_objects) {
 465                struct sha1_array sa = SHA1_ARRAY_INIT;
 466                struct object_cb_data cb;
 467
 468                for_each_loose_object(batch_loose_object, &sa, 0);
 469                for_each_packed_object(batch_packed_object, &sa, 0);
 470
 471                cb.opt = opt;
 472                cb.expand = &data;
 473                sha1_array_for_each_unique(&sa, batch_object_cb, &cb);
 474
 475                sha1_array_clear(&sa);
 476                return 0;
 477        }
 478
 479        /*
 480         * We are going to call get_sha1 on a potentially very large number of
 481         * objects. In most large cases, these will be actual object sha1s. The
 482         * cost to double-check that each one is not also a ref (just so we can
 483         * warn) ends up dwarfing the actual cost of the object lookups
 484         * themselves. We can work around it by just turning off the warning.
 485         */
 486        save_warning = warn_on_object_refname_ambiguity;
 487        warn_on_object_refname_ambiguity = 0;
 488
 489        while (strbuf_getline(&buf, stdin) != EOF) {
 490                if (data.split_on_whitespace) {
 491                        /*
 492                         * Split at first whitespace, tying off the beginning
 493                         * of the string and saving the remainder (or NULL) in
 494                         * data.rest.
 495                         */
 496                        char *p = strpbrk(buf.buf, " \t");
 497                        if (p) {
 498                                while (*p && strchr(" \t", *p))
 499                                        *p++ = '\0';
 500                        }
 501                        data.rest = p;
 502                }
 503
 504                batch_one_object(buf.buf, opt, &data);
 505        }
 506
 507        strbuf_release(&buf);
 508        warn_on_object_refname_ambiguity = save_warning;
 509        return retval;
 510}
 511
 512static const char * const cat_file_usage[] = {
 513        N_("git cat-file (-t [--allow-unknown-type] | -s [--allow-unknown-type] | -e | -p | <type> | --textconv | --filters) [--path=<path>] <object>"),
 514        N_("git cat-file (--batch | --batch-check) [--follow-symlinks] [--textconv | --filters]"),
 515        NULL
 516};
 517
 518static int git_cat_file_config(const char *var, const char *value, void *cb)
 519{
 520        if (userdiff_config(var, value) < 0)
 521                return -1;
 522
 523        return git_default_config(var, value, cb);
 524}
 525
 526static int batch_option_callback(const struct option *opt,
 527                                 const char *arg,
 528                                 int unset)
 529{
 530        struct batch_options *bo = opt->value;
 531
 532        if (bo->enabled) {
 533                return 1;
 534        }
 535
 536        bo->enabled = 1;
 537        bo->print_contents = !strcmp(opt->long_name, "batch");
 538        bo->format = arg;
 539
 540        return 0;
 541}
 542
 543int cmd_cat_file(int argc, const char **argv, const char *prefix)
 544{
 545        int opt = 0;
 546        const char *exp_type = NULL, *obj_name = NULL;
 547        struct batch_options batch = {0};
 548        int unknown_type = 0;
 549
 550        const struct option options[] = {
 551                OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
 552                OPT_CMDMODE('t', NULL, &opt, N_("show object type"), 't'),
 553                OPT_CMDMODE('s', NULL, &opt, N_("show object size"), 's'),
 554                OPT_CMDMODE('e', NULL, &opt,
 555                            N_("exit with zero when there's no error"), 'e'),
 556                OPT_CMDMODE('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
 557                OPT_CMDMODE(0, "textconv", &opt,
 558                            N_("for blob objects, run textconv on object's content"), 'c'),
 559                OPT_CMDMODE(0, "filters", &opt,
 560                            N_("for blob objects, run filters on object's content"), 'w'),
 561                OPT_STRING(0, "path", &force_path, N_("blob"),
 562                           N_("use a specific path for --textconv/--filters")),
 563                OPT_BOOL(0, "allow-unknown-type", &unknown_type,
 564                          N_("allow -s and -t to work with broken/corrupt objects")),
 565                OPT_BOOL(0, "buffer", &batch.buffer_output, N_("buffer --batch output")),
 566                { OPTION_CALLBACK, 0, "batch", &batch, "format",
 567                        N_("show info and content of objects fed from the standard input"),
 568                        PARSE_OPT_OPTARG, batch_option_callback },
 569                { OPTION_CALLBACK, 0, "batch-check", &batch, "format",
 570                        N_("show info about objects fed from the standard input"),
 571                        PARSE_OPT_OPTARG, batch_option_callback },
 572                OPT_BOOL(0, "follow-symlinks", &batch.follow_symlinks,
 573                         N_("follow in-tree symlinks (used with --batch or --batch-check)")),
 574                OPT_BOOL(0, "batch-all-objects", &batch.all_objects,
 575                         N_("show all objects with --batch or --batch-check")),
 576                OPT_END()
 577        };
 578
 579        git_config(git_cat_file_config, NULL);
 580
 581        batch.buffer_output = -1;
 582        argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 583
 584        if (opt) {
 585                if (batch.enabled && (opt == 'c' || opt == 'w'))
 586                        batch.cmdmode = opt;
 587                else if (argc == 1)
 588                        obj_name = argv[0];
 589                else
 590                        usage_with_options(cat_file_usage, options);
 591        }
 592        if (!opt && !batch.enabled) {
 593                if (argc == 2) {
 594                        exp_type = argv[0];
 595                        obj_name = argv[1];
 596                } else
 597                        usage_with_options(cat_file_usage, options);
 598        }
 599        if (batch.enabled) {
 600                if (batch.cmdmode != opt || argc)
 601                        usage_with_options(cat_file_usage, options);
 602                if (batch.cmdmode && batch.all_objects)
 603                        die("--batch-all-objects cannot be combined with "
 604                            "--textconv nor with --filters");
 605        }
 606
 607        if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
 608                usage_with_options(cat_file_usage, options);
 609        }
 610
 611        if (force_path && opt != 'c' && opt != 'w') {
 612                error("--path=<path> needs --textconv or --filters");
 613                usage_with_options(cat_file_usage, options);
 614        }
 615
 616        if (force_path && batch.enabled) {
 617                error("--path=<path> incompatible with --batch");
 618                usage_with_options(cat_file_usage, options);
 619        }
 620
 621        if (batch.buffer_output < 0)
 622                batch.buffer_output = batch.all_objects;
 623
 624        if (batch.enabled)
 625                return batch_objects(&batch);
 626
 627        if (unknown_type && opt != 't' && opt != 's')
 628                die("git cat-file --allow-unknown-type: use with -s or -t");
 629        return cat_one_file(opt, exp_type, obj_name, unknown_type);
 630}