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