bundle.c

   1 #include "cache.h"
   2 #include "lockfile.h"
   3 #include "bundle.h"
   4 #include "object-store.h"
   5 #include "repository.h"
   6 #include "object.h"
   7 #include "commit.h"
   8 #include "diff.h"
   9 #include "revision.h"
  10 #include "list-objects.h"
  11 #include "run-command.h"
  12 #include "refs.h"
  13 #include "strvec.h"
  14
  15
  16 static const char v2_bundle_signature[] = "# v2 git bundle\n";
  17 static const char v3_bundle_signature[] = "# v3 git bundle\n";
  18 static struct {
  19         int version;
  20         const char *signature;
  21 } bundle_sigs[] = {
  22         { 2, v2_bundle_signature },
  23         { 3, v3_bundle_signature },
  24 };
  25
  26 void bundle_header_init(struct bundle_header *header)
  27 {
  28         struct bundle_header blank = BUNDLE_HEADER_INIT;
  29         memcpy(header, &blank, sizeof(*header));
  30 }
  31
  32 void bundle_header_release(struct bundle_header *header)
  33 {
  34         string_list_clear(&header->prerequisites, 1);
  35         string_list_clear(&header->references, 1);
  36 }
  37
  38 static int parse_capability(struct bundle_header *header, const char *capability)
  39 {
  40         const char *arg;
  41         if (skip_prefix(capability, "object-format=", &arg)) {
  42                 int algo = hash_algo_by_name(arg);
  43                 if (algo == GIT_HASH_UNKNOWN)
  44                         return error(_("unrecognized bundle hash algorithm: %s"), arg);
  45                 header->hash_algo = &hash_algos[algo];
  46                 return 0;
  47         }
  48         return error(_("unknown capability '%s'"), capability);
  49 }
  50
  51 static int parse_bundle_signature(struct bundle_header *header, const char *line)
  52 {
  53         int i;
  54
  55         for (i = 0; i < ARRAY_SIZE(bundle_sigs); i++) {
  56                 if (!strcmp(line, bundle_sigs[i].signature)) {
  57                         header->version = bundle_sigs[i].version;
  58                         return 0;
  59                 }
  60         }
  61         return -1;
  62 }
  63
  64 static int parse_bundle_header(int fd, struct bundle_header *header,
  65                                const char *report_path)
  66 {
  67         struct strbuf buf = STRBUF_INIT;
  68         int status = 0;
  69
  70         /* The bundle header begins with the signature */
  71         if (strbuf_getwholeline_fd(&buf, fd, '\n') ||
  72             parse_bundle_signature(header, buf.buf)) {
  73                 if (report_path)
  74                         error(_("'%s' does not look like a v2 or v3 bundle file"),
  75                               report_path);
  76                 status = -1;
  77                 goto abort;
  78         }
  79
  80         header->hash_algo = the_hash_algo;
  81
  82         /* The bundle header ends with an empty line */
  83         while (!strbuf_getwholeline_fd(&buf, fd, '\n') &&
  84                buf.len && buf.buf[0] != '\n') {
  85                 struct object_id oid;
  86                 int is_prereq = 0;
  87                 const char *p;
  88
  89                 strbuf_rtrim(&buf);
  90
  91                 if (header->version == 3 && *buf.buf == '@') {
  92                         if (parse_capability(header, buf.buf + 1)) {
  93                                 status = -1;
  94                                 break;
  95                         }
  96                         continue;
  97                 }
  98
  99                 if (*buf.buf == '-') {
 100                         is_prereq = 1;
 101                         strbuf_remove(&buf, 0, 1);
 102                 }
 103
 104                 /*
 105                  * Tip lines have object name, SP, and refname.
 106                  * Prerequisites have object name that is optionally
 107                  * followed by SP and subject line.
 108                  */
 109                 if (parse_oid_hex_algop(buf.buf, &oid, &p, header->hash_algo) ||
 110                     (*p && !isspace(*p)) ||
 111                     (!is_prereq && !*p)) {
 112                         if (report_path)
 113                                 error(_("unrecognized header: %s%s (%d)"),
 114                                       (is_prereq ? "-" : ""), buf.buf, (int)buf.len);
 115                         status = -1;
 116                         break;
 117                 } else {
 118                         struct object_id *dup = oiddup(&oid);
 119                         if (is_prereq)
 120                                 string_list_append(&header->prerequisites, "")->util = dup;
 121                         else
 122                                 string_list_append(&header->references, p + 1)->util = dup;
 123                 }
 124         }
 125
 126  abort:
 127         if (status) {
 128                 close(fd);
 129                 fd = -1;
 130         }
 131         strbuf_release(&buf);
 132         return fd;
 133 }
 134
 135 int read_bundle_header(const char *path, struct bundle_header *header)
 136 {
 137         int fd = open(path, O_RDONLY);
 138
 139         if (fd < 0)
 140                 return error(_("could not open '%s'"), path);
 141         return parse_bundle_header(fd, header, path);
 142 }
 143
 144 int is_bundle(const char *path, int quiet)
 145 {
 146         struct bundle_header header = BUNDLE_HEADER_INIT;
 147         int fd = open(path, O_RDONLY);
 148
 149         if (fd < 0)
 150                 return 0;
 151         fd = parse_bundle_header(fd, &header, quiet ? NULL : path);
 152         if (fd >= 0)
 153                 close(fd);
 154         bundle_header_release(&header);
 155         return (fd >= 0);
 156 }
 157
 158 static int list_refs(struct string_list *r, int argc, const char **argv)
 159 {
 160         int i;
 161
 162         for (i = 0; i < r->nr; i++) {
 163                 struct object_id *oid;
 164                 const char *name;
 165
 166                 if (argc > 1) {
 167                         int j;
 168                         for (j = 1; j < argc; j++)
 169                                 if (!strcmp(r->items[i].string, argv[j]))
 170                                         break;
 171                         if (j == argc)
 172                                 continue;
 173                 }
 174
 175                 oid = r->items[i].util;
 176                 name = r->items[i].string;
 177                 printf("%s %s\n", oid_to_hex(oid), name);
 178         }
 179         return 0;
 180 }
 181
 182 /* Remember to update object flag allocation in object.h */
 183 #define PREREQ_MARK (1u<<16)
 184
 185 int verify_bundle(struct repository *r,
 186                   struct bundle_header *header,
 187                   int verbose)
 188 {
 189         /*
 190          * Do fast check, then if any prereqs are missing then go line by line
 191          * to be verbose about the errors
 192          */
 193         struct string_list *p = &header->prerequisites;
 194         struct rev_info revs;
 195         const char *argv[] = {NULL, "--all", NULL};
 196         struct commit *commit;
 197         int i, ret = 0, req_nr;
 198         const char *message = _("Repository lacks these prerequisite commits:");
 199
 200         if (!r || !r->objects || !r->objects->odb)
 201                 return error(_("need a repository to verify a bundle"));
 202
 203         repo_init_revisions(r, &revs, NULL);
 204         for (i = 0; i < p->nr; i++) {
 205                 struct string_list_item *e = p->items + i;
 206                 const char *name = e->string;
 207                 struct object_id *oid = e->util;
 208                 struct object *o = parse_object(r, oid);
 209                 if (o) {
 210                         o->flags |= PREREQ_MARK;
 211                         add_pending_object(&revs, o, name);
 212                         continue;
 213                 }
 214                 if (++ret == 1)
 215                         error("%s", message);
 216                 error("%s %s", oid_to_hex(oid), name);
 217         }
 218         if (revs.pending.nr != p->nr)
 219                 return ret;
 220         req_nr = revs.pending.nr;
 221         setup_revisions(2, argv, &revs, NULL);
 222
 223         if (prepare_revision_walk(&revs))
 224                 die(_("revision walk setup failed"));
 225
 226         i = req_nr;
 227         while (i && (commit = get_revision(&revs)))
 228                 if (commit->object.flags & PREREQ_MARK)
 229                         i--;
 230
 231         for (i = 0; i < p->nr; i++) {
 232                 struct string_list_item *e = p->items + i;
 233                 const char *name = e->string;
 234                 const struct object_id *oid = e->util;
 235                 struct object *o = parse_object(r, oid);
 236                 assert(o); /* otherwise we'd have returned early */
 237                 if (o->flags & SHOWN)
 238                         continue;
 239                 if (++ret == 1)
 240                         error("%s", message);
 241                 error("%s %s", oid_to_hex(oid), name);
 242         }
 243
 244         /* Clean up objects used, as they will be reused. */
 245         for (i = 0; i < p->nr; i++) {
 246                 struct string_list_item *e = p->items + i;
 247                 struct object_id *oid = e->util;
 248                 commit = lookup_commit_reference_gently(r, oid, 1);
 249                 if (commit)
 250                         clear_commit_marks(commit, ALL_REV_FLAGS);
 251         }
 252
 253         if (verbose) {
 254                 struct string_list *r;
 255
 256                 r = &header->references;
 257                 printf_ln(Q_("The bundle contains this ref:",
 258                              "The bundle contains these %d refs:",
 259                              r->nr),
 260                           r->nr);
 261                 list_refs(r, 0, NULL);
 262                 r = &header->prerequisites;
 263                 if (!r->nr) {
 264                         printf_ln(_("The bundle records a complete history."));
 265                 } else {
 266                         printf_ln(Q_("The bundle requires this ref:",
 267                                      "The bundle requires these %d refs:",
 268                                      r->nr),
 269                                   r->nr);
 270                         list_refs(r, 0, NULL);
 271                 }
 272         }
 273         return ret;
 274 }
 275
 276 int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
 277 {
 278         return list_refs(&header->references, argc, argv);
 279 }
 280
 281 static int is_tag_in_date_range(struct object *tag, struct rev_info *revs)
 282 {
 283         unsigned long size;
 284         enum object_type type;
 285         char *buf = NULL, *line, *lineend;
 286         timestamp_t date;
 287         int result = 1;
 288
 289         if (revs->max_age == -1 && revs->min_age == -1)
 290                 goto out;
 291
 292         buf = read_object_file(&tag->oid, &type, &size);
 293         if (!buf)
 294                 goto out;
 295         line = memmem(buf, size, "\ntagger ", 8);
 296         if (!line++)
 297                 goto out;
 298         lineend = memchr(line, '\n', buf + size - line);
 299         line = memchr(line, '>', lineend ? lineend - line : buf + size - line);
 300         if (!line++)
 301                 goto out;
 302         date = parse_timestamp(line, NULL, 10);
 303         result = (revs->max_age == -1 || revs->max_age < date) &&
 304                 (revs->min_age == -1 || revs->min_age > date);
 305 out:
 306         free(buf);
 307         return result;
 308 }
 309
 310
 311 /* Write the pack data to bundle_fd */
 312 static int write_pack_data(int bundle_fd, struct rev_info *revs, struct strvec *pack_options)
 313 {
 314         struct child_process pack_objects = CHILD_PROCESS_INIT;
 315         int i;
 316
 317         strvec_pushl(&pack_objects.args,
 318                      "pack-objects",
 319                      "--stdout", "--thin", "--delta-base-offset",
 320                      NULL);
 321         strvec_pushv(&pack_objects.args, pack_options->v);
 322         pack_objects.in = -1;
 323         pack_objects.out = bundle_fd;
 324         pack_objects.git_cmd = 1;
 325
 326         /*
 327          * start_command() will close our descriptor if it's >1. Duplicate it
 328          * to avoid surprising the caller.
 329          */
 330         if (pack_objects.out > 1) {
 331                 pack_objects.out = dup(pack_objects.out);
 332                 if (pack_objects.out < 0) {
 333                         error_errno(_("unable to dup bundle descriptor"));
 334                         child_process_clear(&pack_objects);
 335                         return -1;
 336                 }
 337         }
 338
 339         if (start_command(&pack_objects))
 340                 return error(_("Could not spawn pack-objects"));
 341
 342         for (i = 0; i < revs->pending.nr; i++) {
 343                 struct object *object = revs->pending.objects[i].item;
 344                 if (object->flags & UNINTERESTING)
 345                         write_or_die(pack_objects.in, "^", 1);
 346                 write_or_die(pack_objects.in, oid_to_hex(&object->oid), the_hash_algo->hexsz);
 347                 write_or_die(pack_objects.in, "\n", 1);
 348         }
 349         close(pack_objects.in);
 350         if (finish_command(&pack_objects))
 351                 return error(_("pack-objects died"));
 352         return 0;
 353 }
 354
 355 /*
 356  * Write out bundle refs based on the tips already
 357  * parsed into revs.pending. As a side effect, may
 358  * manipulate revs.pending to include additional
 359  * necessary objects (like tags).
 360  *
 361  * Returns the number of refs written, or negative
 362  * on error.
 363  */
 364 static int write_bundle_refs(int bundle_fd, struct rev_info *revs)
 365 {
 366         int i;
 367         int ref_count = 0;
 368
 369         for (i = 0; i < revs->pending.nr; i++) {
 370                 struct object_array_entry *e = revs->pending.objects + i;
 371                 struct object_id oid;
 372                 char *ref;
 373                 const char *display_ref;
 374                 int flag;
 375
 376                 if (e->item->flags & UNINTERESTING)
 377                         continue;
 378                 if (dwim_ref(e->name, strlen(e->name), &oid, &ref, 0) != 1)
 379                         goto skip_write_ref;
 380                 if (read_ref_full(e->name, RESOLVE_REF_READING, &oid, &flag))
 381                         flag = 0;
 382                 display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
 383
 384                 if (e->item->type == OBJ_TAG &&
 385                                 !is_tag_in_date_range(e->item, revs)) {
 386                         e->item->flags |= UNINTERESTING;
 387                         goto skip_write_ref;
 388                 }
 389
 390                 /*
 391                  * Make sure the refs we wrote out is correct; --max-count and
 392                  * other limiting options could have prevented all the tips
 393                  * from getting output.
 394                  *
 395                  * Non commit objects such as tags and blobs do not have
 396                  * this issue as they are not affected by those extra
 397                  * constraints.
 398                  */
 399                 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
 400                         warning(_("ref '%s' is excluded by the rev-list options"),
 401                                 e->name);
 402                         goto skip_write_ref;
 403                 }
 404                 /*
 405                  * If you run "git bundle create bndl v1.0..v2.0", the
 406                  * name of the positive ref is "v2.0" but that is the
 407                  * commit that is referenced by the tag, and not the tag
 408                  * itself.
 409                  */
 410                 if (!oideq(&oid, &e->item->oid)) {
 411                         /*
 412                          * Is this the positive end of a range expressed
 413                          * in terms of a tag (e.g. v2.0 from the range
 414                          * "v1.0..v2.0")?
 415                          */
 416                         struct commit *one = lookup_commit_reference(revs->repo, &oid);
 417                         struct object *obj;
 418
 419                         if (e->item == &(one->object)) {
 420                                 /*
 421                                  * Need to include e->name as an
 422                                  * independent ref to the pack-objects
 423                                  * input, so that the tag is included
 424                                  * in the output; otherwise we would
 425                                  * end up triggering "empty bundle"
 426                                  * error.
 427                                  */
 428                                 obj = parse_object_or_die(&oid, e->name);
 429                                 obj->flags |= SHOWN;
 430                                 add_pending_object(revs, obj, e->name);
 431                         }
 432                         goto skip_write_ref;
 433                 }
 434
 435                 ref_count++;
 436                 write_or_die(bundle_fd, oid_to_hex(&e->item->oid), the_hash_algo->hexsz);
 437                 write_or_die(bundle_fd, " ", 1);
 438                 write_or_die(bundle_fd, display_ref, strlen(display_ref));
 439                 write_or_die(bundle_fd, "\n", 1);
 440  skip_write_ref:
 441                 free(ref);
 442         }
 443
 444         /* end header */
 445         write_or_die(bundle_fd, "\n", 1);
 446         return ref_count;
 447 }
 448
 449 struct bundle_prerequisites_info {
 450         struct object_array *pending;
 451         int fd;
 452 };
 453
 454 static void write_bundle_prerequisites(struct commit *commit, void *data)
 455 {
 456         struct bundle_prerequisites_info *bpi = data;
 457         struct object *object;
 458         struct pretty_print_context ctx = { 0 };
 459         struct strbuf buf = STRBUF_INIT;
 460
 461         if (!(commit->object.flags & BOUNDARY))
 462                 return;
 463         strbuf_addf(&buf, "-%s ", oid_to_hex(&commit->object.oid));
 464         write_or_die(bpi->fd, buf.buf, buf.len);
 465
 466         ctx.fmt = CMIT_FMT_ONELINE;
 467         ctx.output_encoding = get_log_output_encoding();
 468         strbuf_reset(&buf);
 469         pretty_print_commit(&ctx, commit, &buf);
 470         strbuf_trim(&buf);
 471
 472         object = (struct object *)commit;
 473         object->flags |= UNINTERESTING;
 474         add_object_array_with_path(object, buf.buf, bpi->pending, S_IFINVALID,
 475                                    NULL);
 476         strbuf_addch(&buf, '\n');
 477         write_or_die(bpi->fd, buf.buf, buf.len);
 478         strbuf_release(&buf);
 479 }
 480
 481 int create_bundle(struct repository *r, const char *path,
 482                   int argc, const char **argv, struct strvec *pack_options, int version)
 483 {
 484         struct lock_file lock = LOCK_INIT;
 485         int bundle_fd = -1;
 486         int bundle_to_stdout;
 487         int ref_count = 0;
 488         struct rev_info revs, revs_copy;
 489         int min_version = the_hash_algo == &hash_algos[GIT_HASH_SHA1] ? 2 : 3;
 490         struct bundle_prerequisites_info bpi;
 491         int i;
 492
 493         bundle_to_stdout = !strcmp(path, "-");
 494         if (bundle_to_stdout)
 495                 bundle_fd = 1;
 496         else
 497                 bundle_fd = hold_lock_file_for_update(&lock, path,
 498                                                       LOCK_DIE_ON_ERROR);
 499
 500         if (version == -1)
 501                 version = min_version;
 502
 503         if (version < 2 || version > 3) {
 504                 die(_("unsupported bundle version %d"), version);
 505         } else if (version < min_version) {
 506                 die(_("cannot write bundle version %d with algorithm %s"), version, the_hash_algo->name);
 507         } else if (version == 2) {
 508                 write_or_die(bundle_fd, v2_bundle_signature, strlen(v2_bundle_signature));
 509         } else {
 510                 const char *capability = "@object-format=";
 511                 write_or_die(bundle_fd, v3_bundle_signature, strlen(v3_bundle_signature));
 512                 write_or_die(bundle_fd, capability, strlen(capability));
 513                 write_or_die(bundle_fd, the_hash_algo->name, strlen(the_hash_algo->name));
 514                 write_or_die(bundle_fd, "\n", 1);
 515         }
 516
 517         /* init revs to list objects for pack-objects later */
 518         save_commit_buffer = 0;
 519         repo_init_revisions(r, &revs, NULL);
 520
 521         argc = setup_revisions(argc, argv, &revs, NULL);
 522
 523         if (argc > 1) {
 524                 error(_("unrecognized argument: %s"), argv[1]);
 525                 goto err;
 526         }
 527
 528         /* save revs.pending in revs_copy for later use */
 529         memcpy(&revs_copy, &revs, sizeof(revs));
 530         revs_copy.pending.nr = 0;
 531         revs_copy.pending.alloc = 0;
 532         revs_copy.pending.objects = NULL;
 533         for (i = 0; i < revs.pending.nr; i++) {
 534                 struct object_array_entry *e = revs.pending.objects + i;
 535                 if (e)
 536                         add_object_array_with_path(e->item, e->name,
 537                                                    &revs_copy.pending,
 538                                                    e->mode, e->path);
 539         }
 540
 541         /* write prerequisites */
 542         revs.boundary = 1;
 543         if (prepare_revision_walk(&revs))
 544                 die("revision walk setup failed");
 545         bpi.fd = bundle_fd;
 546         bpi.pending = &revs_copy.pending;
 547         traverse_commit_list(&revs, write_bundle_prerequisites, NULL, &bpi);
 548         object_array_remove_duplicates(&revs_copy.pending);
 549
 550         /* write bundle refs */
 551         ref_count = write_bundle_refs(bundle_fd, &revs_copy);
 552         if (!ref_count)
 553                 die(_("Refusing to create empty bundle."));
 554         else if (ref_count < 0)
 555                 goto err;
 556
 557         /* write pack */
 558         if (write_pack_data(bundle_fd, &revs_copy, pack_options))
 559                 goto err;
 560
 561         if (!bundle_to_stdout) {
 562                 if (commit_lock_file(&lock))
 563                         die_errno(_("cannot create '%s'"), path);
 564         }
 565         return 0;
 566 err:
 567         rollback_lock_file(&lock);
 568         return -1;
 569 }
 570
 571 int unbundle(struct repository *r, struct bundle_header *header,
 572              int bundle_fd, struct strvec *extra_index_pack_args)
 573 {
 574         struct child_process ip = CHILD_PROCESS_INIT;
 575         strvec_pushl(&ip.args, "index-pack", "--fix-thin", "--stdin", NULL);
 576
 577         if (extra_index_pack_args) {
 578                 strvec_pushv(&ip.args, extra_index_pack_args->v);
 579                 strvec_clear(extra_index_pack_args);
 580         }
 581
 582         if (verify_bundle(r, header, 0))
 583                 return -1;
 584         ip.in = bundle_fd;
 585         ip.no_stdout = 1;
 586         ip.git_cmd = 1;
 587         if (run_command(&ip))
 588                 return error(_("index-pack died"));
 589         return 0;
 590 }