bundle.c

   1 #include "cache.h"
   2 #include "bundle.h"
   3 #include "object.h"
   4 #include "commit.h"
   5 #include "diff.h"
   6 #include "revision.h"
   7 #include "list-objects.h"
   8 #include "run-command.h"
   9 #include "refs.h"
  10
  11 static const char bundle_signature[] = "# v2 git bundle\n";
  12
  13 static void add_to_ref_list(const unsigned char *sha1, const char *name,
  14                 struct ref_list *list)
  15 {
  16         if (list->nr + 1 >= list->alloc) {
  17                 list->alloc = alloc_nr(list->nr + 1);
  18                 list->list = xrealloc(list->list,
  19                                 list->alloc * sizeof(list->list[0]));
  20         }
  21         memcpy(list->list[list->nr].sha1, sha1, 20);
  22         list->list[list->nr].name = xstrdup(name);
  23         list->nr++;
  24 }
  25
  26 /* Eventually this should go to strbuf.[ch] */
  27 static int strbuf_readline_fd(struct strbuf *sb, int fd)
  28 {
  29         strbuf_reset(sb);
  30
  31         while (1) {
  32                 char ch;
  33                 ssize_t len = xread(fd, &ch, 1);
  34                 if (len < 0)
  35                         return -1;
  36                 strbuf_addch(sb, ch);
  37                 if (ch == '\n')
  38                         break;
  39         }
  40         return 0;
  41 }
  42
  43 static int parse_bundle_header(int fd, struct bundle_header *header,
  44                                const char *report_path)
  45 {
  46         struct strbuf buf = STRBUF_INIT;
  47         int status = 0;
  48
  49         /* The bundle header begins with the signature */
  50         if (strbuf_readline_fd(&buf, fd) ||
  51             strcmp(buf.buf, bundle_signature)) {
  52                 if (report_path)
  53                         error("'%s' does not look like a v2 bundle file",
  54                               report_path);
  55                 status = -1;
  56                 goto abort;
  57         }
  58
  59         /* The bundle header ends with an empty line */
  60         while (!strbuf_readline_fd(&buf, fd) &&
  61                buf.len && buf.buf[0] != '\n') {
  62                 unsigned char sha1[20];
  63                 int is_prereq = 0;
  64
  65                 if (*buf.buf == '-') {
  66                         is_prereq = 1;
  67                         strbuf_remove(&buf, 0, 1);
  68                 }
  69                 strbuf_rtrim(&buf);
  70
  71                 /*
  72                  * Tip lines have object name, SP, and refname.
  73                  * Prerequisites have object name that is optionally
  74                  * followed by SP and subject line.
  75                  */
  76                 if (get_sha1_hex(buf.buf, sha1) ||
  77                     (40 <= buf.len && !isspace(buf.buf[40])) ||
  78                     (!is_prereq && buf.len <= 40)) {
  79                         if (report_path)
  80                                 error("unrecognized header: %s%s (%d)",
  81                                       (is_prereq ? "-" : ""), buf.buf, (int)buf.len);
  82                         status = -1;
  83                         break;
  84                 } else {
  85                         if (is_prereq)
  86                                 add_to_ref_list(sha1, "", &header->prerequisites);
  87                         else
  88                                 add_to_ref_list(sha1, buf.buf + 41, &header->references);
  89                 }
  90         }
  91
  92  abort:
  93         if (status) {
  94                 close(fd);
  95                 fd = -1;
  96         }
  97         strbuf_release(&buf);
  98         return fd;
  99 }
 100
 101 int read_bundle_header(const char *path, struct bundle_header *header)
 102 {
 103         int fd = open(path, O_RDONLY);
 104
 105         if (fd < 0)
 106                 return error("could not open '%s'", path);
 107         return parse_bundle_header(fd, header, path);
 108 }
 109
 110 int is_bundle(const char *path, int quiet)
 111 {
 112         struct bundle_header header;
 113         int fd = open(path, O_RDONLY);
 114
 115         if (fd < 0)
 116                 return 0;
 117         memset(&header, 0, sizeof(header));
 118         fd = parse_bundle_header(fd, &header, quiet ? NULL : path);
 119         if (fd >= 0)
 120                 close(fd);
 121         return (fd >= 0);
 122 }
 123
 124 static int list_refs(struct ref_list *r, int argc, const char **argv)
 125 {
 126         int i;
 127
 128         for (i = 0; i < r->nr; i++) {
 129                 if (argc > 1) {
 130                         int j;
 131                         for (j = 1; j < argc; j++)
 132                                 if (!strcmp(r->list[i].name, argv[j]))
 133                                         break;
 134                         if (j == argc)
 135                                 continue;
 136                 }
 137                 printf("%s %s\n", sha1_to_hex(r->list[i].sha1),
 138                                 r->list[i].name);
 139         }
 140         return 0;
 141 }
 142
 143 #define PREREQ_MARK (1u<<16)
 144
 145 int verify_bundle(struct bundle_header *header, int verbose)
 146 {
 147         /*
 148          * Do fast check, then if any prereqs are missing then go line by line
 149          * to be verbose about the errors
 150          */
 151         struct ref_list *p = &header->prerequisites;
 152         struct rev_info revs;
 153         const char *argv[] = {NULL, "--all", NULL};
 154         struct object_array refs;
 155         struct commit *commit;
 156         int i, ret = 0, req_nr;
 157         const char *message = "Repository lacks these prerequisite commits:";
 158
 159         init_revisions(&revs, NULL);
 160         for (i = 0; i < p->nr; i++) {
 161                 struct ref_list_entry *e = p->list + i;
 162                 struct object *o = parse_object(e->sha1);
 163                 if (o) {
 164                         o->flags |= PREREQ_MARK;
 165                         add_pending_object(&revs, o, e->name);
 166                         continue;
 167                 }
 168                 if (++ret == 1)
 169                         error("%s", message);
 170                 error("%s %s", sha1_to_hex(e->sha1), e->name);
 171         }
 172         if (revs.pending.nr != p->nr)
 173                 return ret;
 174         req_nr = revs.pending.nr;
 175         setup_revisions(2, argv, &revs, NULL);
 176
 177         memset(&refs, 0, sizeof(struct object_array));
 178         for (i = 0; i < revs.pending.nr; i++) {
 179                 struct object_array_entry *e = revs.pending.objects + i;
 180                 add_object_array(e->item, e->name, &refs);
 181         }
 182
 183         if (prepare_revision_walk(&revs))
 184                 die("revision walk setup failed");
 185
 186         i = req_nr;
 187         while (i && (commit = get_revision(&revs)))
 188                 if (commit->object.flags & PREREQ_MARK)
 189                         i--;
 190
 191         for (i = 0; i < req_nr; i++)
 192                 if (!(refs.objects[i].item->flags & SHOWN)) {
 193                         if (++ret == 1)
 194                                 error("%s", message);
 195                         error("%s %s", sha1_to_hex(refs.objects[i].item->sha1),
 196                                 refs.objects[i].name);
 197                 }
 198
 199         for (i = 0; i < refs.nr; i++)
 200                 clear_commit_marks((struct commit *)refs.objects[i].item, -1);
 201
 202         if (verbose) {
 203                 struct ref_list *r;
 204
 205                 r = &header->references;
 206                 printf("The bundle contains %d ref%s\n",
 207                        r->nr, (1 < r->nr) ? "s" : "");
 208                 list_refs(r, 0, NULL);
 209                 r = &header->prerequisites;
 210                 printf("The bundle requires these %d ref%s\n",
 211                        r->nr, (1 < r->nr) ? "s" : "");
 212                 list_refs(r, 0, NULL);
 213         }
 214         return ret;
 215 }
 216
 217 int list_bundle_refs(struct bundle_header *header, int argc, const char **argv)
 218 {
 219         return list_refs(&header->references, argc, argv);
 220 }
 221
 222 static int is_tag_in_date_range(struct object *tag, struct rev_info *revs)
 223 {
 224         unsigned long size;
 225         enum object_type type;
 226         char *buf, *line, *lineend;
 227         unsigned long date;
 228
 229         if (revs->max_age == -1 && revs->min_age == -1)
 230                 return 1;
 231
 232         buf = read_sha1_file(tag->sha1, &type, &size);
 233         if (!buf)
 234                 return 1;
 235         line = memmem(buf, size, "\ntagger ", 8);
 236         if (!line++)
 237                 return 1;
 238         lineend = memchr(line, buf + size - line, '\n');
 239         line = memchr(line, lineend ? lineend - line : buf + size - line, '>');
 240         if (!line++)
 241                 return 1;
 242         date = strtoul(line, NULL, 10);
 243         free(buf);
 244         return (revs->max_age == -1 || revs->max_age < date) &&
 245                 (revs->min_age == -1 || revs->min_age > date);
 246 }
 247
 248 int create_bundle(struct bundle_header *header, const char *path,
 249                 int argc, const char **argv)
 250 {
 251         static struct lock_file lock;
 252         int bundle_fd = -1;
 253         int bundle_to_stdout;
 254         const char **argv_boundary = xmalloc((argc + 4) * sizeof(const char *));
 255         const char **argv_pack = xmalloc(6 * sizeof(const char *));
 256         int i, ref_count = 0;
 257         char buffer[1024];
 258         struct rev_info revs;
 259         struct child_process rls;
 260         FILE *rls_fout;
 261
 262         bundle_to_stdout = !strcmp(path, "-");
 263         if (bundle_to_stdout)
 264                 bundle_fd = 1;
 265         else
 266                 bundle_fd = hold_lock_file_for_update(&lock, path,
 267                                                       LOCK_DIE_ON_ERROR);
 268
 269         /* write signature */
 270         write_or_die(bundle_fd, bundle_signature, strlen(bundle_signature));
 271
 272         /* init revs to list objects for pack-objects later */
 273         save_commit_buffer = 0;
 274         init_revisions(&revs, NULL);
 275
 276         /* write prerequisites */
 277         memcpy(argv_boundary + 3, argv + 1, argc * sizeof(const char *));
 278         argv_boundary[0] = "rev-list";
 279         argv_boundary[1] = "--boundary";
 280         argv_boundary[2] = "--pretty=oneline";
 281         argv_boundary[argc + 2] = NULL;
 282         memset(&rls, 0, sizeof(rls));
 283         rls.argv = argv_boundary;
 284         rls.out = -1;
 285         rls.git_cmd = 1;
 286         if (start_command(&rls))
 287                 return -1;
 288         rls_fout = xfdopen(rls.out, "r");
 289         while (fgets(buffer, sizeof(buffer), rls_fout)) {
 290                 unsigned char sha1[20];
 291                 if (buffer[0] == '-') {
 292                         write_or_die(bundle_fd, buffer, strlen(buffer));
 293                         if (!get_sha1_hex(buffer + 1, sha1)) {
 294                                 struct object *object = parse_object(sha1);
 295                                 object->flags |= UNINTERESTING;
 296                                 add_pending_object(&revs, object, buffer);
 297                         }
 298                 } else if (!get_sha1_hex(buffer, sha1)) {
 299                         struct object *object = parse_object(sha1);
 300                         object->flags |= SHOWN;
 301                 }
 302         }
 303         fclose(rls_fout);
 304         if (finish_command(&rls))
 305                 return error("rev-list died");
 306
 307         /* write references */
 308         argc = setup_revisions(argc, argv, &revs, NULL);
 309
 310         if (argc > 1)
 311                 return error("unrecognized argument: %s'", argv[1]);
 312
 313         object_array_remove_duplicates(&revs.pending);
 314
 315         for (i = 0; i < revs.pending.nr; i++) {
 316                 struct object_array_entry *e = revs.pending.objects + i;
 317                 unsigned char sha1[20];
 318                 char *ref;
 319                 const char *display_ref;
 320                 int flag;
 321
 322                 if (e->item->flags & UNINTERESTING)
 323                         continue;
 324                 if (dwim_ref(e->name, strlen(e->name), sha1, &ref) != 1)
 325                         continue;
 326                 if (!resolve_ref(e->name, sha1, 1, &flag))
 327                         flag = 0;
 328                 display_ref = (flag & REF_ISSYMREF) ? e->name : ref;
 329
 330                 if (e->item->type == OBJ_TAG &&
 331                                 !is_tag_in_date_range(e->item, &revs)) {
 332                         e->item->flags |= UNINTERESTING;
 333                         continue;
 334                 }
 335
 336                 /*
 337                  * Make sure the refs we wrote out is correct; --max-count and
 338                  * other limiting options could have prevented all the tips
 339                  * from getting output.
 340                  *
 341                  * Non commit objects such as tags and blobs do not have
 342                  * this issue as they are not affected by those extra
 343                  * constraints.
 344                  */
 345                 if (!(e->item->flags & SHOWN) && e->item->type == OBJ_COMMIT) {
 346                         warning("ref '%s' is excluded by the rev-list options",
 347                                 e->name);
 348                         free(ref);
 349                         continue;
 350                 }
 351                 /*
 352                  * If you run "git bundle create bndl v1.0..v2.0", the
 353                  * name of the positive ref is "v2.0" but that is the
 354                  * commit that is referenced by the tag, and not the tag
 355                  * itself.
 356                  */
 357                 if (hashcmp(sha1, e->item->sha1)) {
 358                         /*
 359                          * Is this the positive end of a range expressed
 360                          * in terms of a tag (e.g. v2.0 from the range
 361                          * "v1.0..v2.0")?
 362                          */
 363                         struct commit *one = lookup_commit_reference(sha1);
 364                         struct object *obj;
 365
 366                         if (e->item == &(one->object)) {
 367                                 /*
 368                                  * Need to include e->name as an
 369                                  * independent ref to the pack-objects
 370                                  * input, so that the tag is included
 371                                  * in the output; otherwise we would
 372                                  * end up triggering "empty bundle"
 373                                  * error.
 374                                  */
 375                                 obj = parse_object(sha1);
 376                                 obj->flags |= SHOWN;
 377                                 add_pending_object(&revs, obj, e->name);
 378                         }
 379                         free(ref);
 380                         continue;
 381                 }
 382
 383                 ref_count++;
 384                 write_or_die(bundle_fd, sha1_to_hex(e->item->sha1), 40);
 385                 write_or_die(bundle_fd, " ", 1);
 386                 write_or_die(bundle_fd, display_ref, strlen(display_ref));
 387                 write_or_die(bundle_fd, "\n", 1);
 388                 free(ref);
 389         }
 390         if (!ref_count)
 391                 die ("Refusing to create empty bundle.");
 392
 393         /* end header */
 394         write_or_die(bundle_fd, "\n", 1);
 395
 396         /* write pack */
 397         argv_pack[0] = "pack-objects";
 398         argv_pack[1] = "--all-progress-implied";
 399         argv_pack[2] = "--stdout";
 400         argv_pack[3] = "--thin";
 401         argv_pack[4] = "--delta-base-offset";
 402         argv_pack[5] = NULL;
 403         memset(&rls, 0, sizeof(rls));
 404         rls.argv = argv_pack;
 405         rls.in = -1;
 406         rls.out = bundle_fd;
 407         rls.git_cmd = 1;
 408         if (start_command(&rls))
 409                 return error("Could not spawn pack-objects");
 410
 411         /*
 412          * start_command closed bundle_fd if it was > 1
 413          * so set the lock fd to -1 so commit_lock_file()
 414          * won't fail trying to close it.
 415          */
 416         lock.fd = -1;
 417
 418         for (i = 0; i < revs.pending.nr; i++) {
 419                 struct object *object = revs.pending.objects[i].item;
 420                 if (object->flags & UNINTERESTING)
 421                         write_or_die(rls.in, "^", 1);
 422                 write_or_die(rls.in, sha1_to_hex(object->sha1), 40);
 423                 write_or_die(rls.in, "\n", 1);
 424         }
 425         close(rls.in);
 426         if (finish_command(&rls))
 427                 return error ("pack-objects died");
 428         if (!bundle_to_stdout) {
 429                 if (commit_lock_file(&lock))
 430                         die_errno("cannot create '%s'", path);
 431         }
 432         return 0;
 433 }
 434
 435 int unbundle(struct bundle_header *header, int bundle_fd)
 436 {
 437         const char *argv_index_pack[] = {"index-pack",
 438                 "--fix-thin", "--stdin", NULL};
 439         struct child_process ip;
 440
 441         if (verify_bundle(header, 0))
 442                 return -1;
 443         memset(&ip, 0, sizeof(ip));
 444         ip.argv = argv_index_pack;
 445         ip.in = bundle_fd;
 446         ip.no_stdout = 1;
 447         ip.git_cmd = 1;
 448         if (run_command(&ip))
 449                 return error("index-pack died");
 450         return 0;
 451 }