git.oblomov.eu Git - git/blob - builtin/fast-export.c

   1 /*
   2  * "git fast-export" builtin command
   3  *
   4  * Copyright (C) 2007 Johannes E. Schindelin
   5  */
   6 #include "builtin.h"
   7 #include "cache.h"
   8 #include "config.h"
   9 #include "refs.h"
  10 #include "refspec.h"
  11 #include "object-store.h"
  12 #include "commit.h"
  13 #include "object.h"
  14 #include "tag.h"
  15 #include "diff.h"
  16 #include "diffcore.h"
  17 #include "log-tree.h"
  18 #include "revision.h"
  19 #include "decorate.h"
  20 #include "string-list.h"
  21 #include "utf8.h"
  22 #include "parse-options.h"
  23 #include "quote.h"
  24 #include "remote.h"
  25 #include "blob.h"
  26 #include "commit-slab.h"
  27
  28 static const char *fast_export_usage[] = {
  29         N_("git fast-export [rev-list-opts]"),
  30         NULL
  31 };
  32
  33 static int progress;
  34 static enum { SIGNED_TAG_ABORT, VERBATIM, WARN, WARN_STRIP, STRIP } signed_tag_mode = SIGNED_TAG_ABORT;
  35 static enum { TAG_FILTERING_ABORT, DROP, REWRITE } tag_of_filtered_mode = TAG_FILTERING_ABORT;
  36 static enum { REENCODE_ABORT, REENCODE_YES, REENCODE_NO } reencode_mode = REENCODE_ABORT;
  37 static int fake_missing_tagger;
  38 static int use_done_feature;
  39 static int no_data;
  40 static int full_tree;
  41 static int reference_excluded_commits;
  42 static int show_original_ids;
  43 static int mark_tags;
  44 static struct string_list extra_refs = STRING_LIST_INIT_NODUP;
  45 static struct string_list tag_refs = STRING_LIST_INIT_NODUP;
  46 static struct refspec refspecs = REFSPEC_INIT_FETCH;
  47 static int anonymize;
  48 static struct revision_sources revision_sources;
  49
  50 static int parse_opt_signed_tag_mode(const struct option *opt,
  51                                      const char *arg, int unset)
  52 {
  53         if (unset || !strcmp(arg, "abort"))
  54                 signed_tag_mode = SIGNED_TAG_ABORT;
  55         else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
  56                 signed_tag_mode = VERBATIM;
  57         else if (!strcmp(arg, "warn"))
  58                 signed_tag_mode = WARN;
  59         else if (!strcmp(arg, "warn-strip"))
  60                 signed_tag_mode = WARN_STRIP;
  61         else if (!strcmp(arg, "strip"))
  62                 signed_tag_mode = STRIP;
  63         else
  64                 return error("Unknown signed-tags mode: %s", arg);
  65         return 0;
  66 }
  67
  68 static int parse_opt_tag_of_filtered_mode(const struct option *opt,
  69                                           const char *arg, int unset)
  70 {
  71         if (unset || !strcmp(arg, "abort"))
  72                 tag_of_filtered_mode = TAG_FILTERING_ABORT;
  73         else if (!strcmp(arg, "drop"))
  74                 tag_of_filtered_mode = DROP;
  75         else if (!strcmp(arg, "rewrite"))
  76                 tag_of_filtered_mode = REWRITE;
  77         else
  78                 return error("Unknown tag-of-filtered mode: %s", arg);
  79         return 0;
  80 }
  81
  82 static int parse_opt_reencode_mode(const struct option *opt,
  83                                    const char *arg, int unset)
  84 {
  85         if (unset) {
  86                 reencode_mode = REENCODE_ABORT;
  87                 return 0;
  88         }
  89
  90         switch (git_parse_maybe_bool(arg)) {
  91         case 0:
  92                 reencode_mode = REENCODE_NO;
  93                 break;
  94         case 1:
  95                 reencode_mode = REENCODE_YES;
  96                 break;
  97         default:
  98                 if (!strcasecmp(arg, "abort"))
  99                         reencode_mode = REENCODE_ABORT;
 100                 else
 101                         return error("Unknown reencoding mode: %s", arg);
 102         }
 103
 104         return 0;
 105 }
 106
 107 static struct decoration idnums;
 108 static uint32_t last_idnum;
 109
 110 static int has_unshown_parent(struct commit *commit)
 111 {
 112         struct commit_list *parent;
 113
 114         for (parent = commit->parents; parent; parent = parent->next)
 115                 if (!(parent->item->object.flags & SHOWN) &&
 116                     !(parent->item->object.flags & UNINTERESTING))
 117                         return 1;
 118         return 0;
 119 }
 120
 121 struct anonymized_entry {
 122         struct hashmap_entry hash;
 123         const char *orig;
 124         size_t orig_len;
 125         const char *anon;
 126         size_t anon_len;
 127 };
 128
 129 static int anonymized_entry_cmp(const void *unused_cmp_data,
 130                                 const struct hashmap_entry *eptr,
 131                                 const struct hashmap_entry *entry_or_key,
 132                                 const void *unused_keydata)
 133 {
 134         const struct anonymized_entry *a, *b;
 135
 136         a = container_of(eptr, const struct anonymized_entry, hash);
 137         b = container_of(entry_or_key, const struct anonymized_entry, hash);
 138
 139         return a->orig_len != b->orig_len ||
 140                 memcmp(a->orig, b->orig, a->orig_len);
 141 }
 142
 143 /*
 144  * Basically keep a cache of X->Y so that we can repeatedly replace
 145  * the same anonymized string with another. The actual generation
 146  * is farmed out to the generate function.
 147  */
 148 static const void *anonymize_mem(struct hashmap *map,
 149                                  void *(*generate)(const void *, size_t *),
 150                                  const void *orig, size_t *len)
 151 {
 152         struct anonymized_entry key, *ret;
 153
 154         if (!map->cmpfn)
 155                 hashmap_init(map, anonymized_entry_cmp, NULL, 0);
 156
 157         hashmap_entry_init(&key.hash, memhash(orig, *len));
 158         key.orig = orig;
 159         key.orig_len = *len;
 160         ret = hashmap_get_entry(map, &key, hash, NULL);
 161
 162         if (!ret) {
 163                 ret = xmalloc(sizeof(*ret));
 164                 hashmap_entry_init(&ret->hash, key.hash.hash);
 165                 ret->orig = xstrdup(orig);
 166                 ret->orig_len = *len;
 167                 ret->anon = generate(orig, len);
 168                 ret->anon_len = *len;
 169                 hashmap_put(map, &ret->hash);
 170         }
 171
 172         *len = ret->anon_len;
 173         return ret->anon;
 174 }
 175
 176 /*
 177  * We anonymize each component of a path individually,
 178  * so that paths a/b and a/c will share a common root.
 179  * The paths are cached via anonymize_mem so that repeated
 180  * lookups for "a" will yield the same value.
 181  */
 182 static void anonymize_path(struct strbuf *out, const char *path,
 183                            struct hashmap *map,
 184                            void *(*generate)(const void *, size_t *))
 185 {
 186         while (*path) {
 187                 const char *end_of_component = strchrnul(path, '/');
 188                 size_t len = end_of_component - path;
 189                 const char *c = anonymize_mem(map, generate, path, &len);
 190                 strbuf_add(out, c, len);
 191                 path = end_of_component;
 192                 if (*path)
 193                         strbuf_addch(out, *path++);
 194         }
 195 }
 196
 197 static inline void *mark_to_ptr(uint32_t mark)
 198 {
 199         return (void *)(uintptr_t)mark;
 200 }
 201
 202 static inline uint32_t ptr_to_mark(void * mark)
 203 {
 204         return (uint32_t)(uintptr_t)mark;
 205 }
 206
 207 static inline void mark_object(struct object *object, uint32_t mark)
 208 {
 209         add_decoration(&idnums, object, mark_to_ptr(mark));
 210 }
 211
 212 static inline void mark_next_object(struct object *object)
 213 {
 214         mark_object(object, ++last_idnum);
 215 }
 216
 217 static int get_object_mark(struct object *object)
 218 {
 219         void *decoration = lookup_decoration(&idnums, object);
 220         if (!decoration)
 221                 return 0;
 222         return ptr_to_mark(decoration);
 223 }
 224
 225 static struct commit *rewrite_commit(struct commit *p)
 226 {
 227         for (;;) {
 228                 if (p->parents && p->parents->next)
 229                         break;
 230                 if (p->object.flags & UNINTERESTING)
 231                         break;
 232                 if (!(p->object.flags & TREESAME))
 233                         break;
 234                 if (!p->parents)
 235                         return NULL;
 236                 p = p->parents->item;
 237         }
 238         return p;
 239 }
 240
 241 static void show_progress(void)
 242 {
 243         static int counter = 0;
 244         if (!progress)
 245                 return;
 246         if ((++counter % progress) == 0)
 247                 printf("progress %d objects\n", counter);
 248 }
 249
 250 /*
 251  * Ideally we would want some transformation of the blob data here
 252  * that is unreversible, but would still be the same size and have
 253  * the same data relationship to other blobs (so that we get the same
 254  * delta and packing behavior as the original). But the first and last
 255  * requirements there are probably mutually exclusive, so let's take
 256  * the easy way out for now, and just generate arbitrary content.
 257  *
 258  * There's no need to cache this result with anonymize_mem, since
 259  * we already handle blob content caching with marks.
 260  */
 261 static char *anonymize_blob(unsigned long *size)
 262 {
 263         static int counter;
 264         struct strbuf out = STRBUF_INIT;
 265         strbuf_addf(&out, "anonymous blob %d", counter++);
 266         *size = out.len;
 267         return strbuf_detach(&out, NULL);
 268 }
 269
 270 static void export_blob(const struct object_id *oid)
 271 {
 272         unsigned long size;
 273         enum object_type type;
 274         char *buf;
 275         struct object *object;
 276         int eaten;
 277
 278         if (no_data)
 279                 return;
 280
 281         if (is_null_oid(oid))
 282                 return;
 283
 284         object = lookup_object(the_repository, oid);
 285         if (object && object->flags & SHOWN)
 286                 return;
 287
 288         if (anonymize) {
 289                 buf = anonymize_blob(&size);
 290                 object = (struct object *)lookup_blob(the_repository, oid);
 291                 eaten = 0;
 292         } else {
 293                 buf = read_object_file(oid, &type, &size);
 294                 if (!buf)
 295                         die("could not read blob %s", oid_to_hex(oid));
 296                 if (check_object_signature(oid, buf, size, type_name(type)) < 0)
 297                         die("oid mismatch in blob %s", oid_to_hex(oid));
 298                 object = parse_object_buffer(the_repository, oid, type,
 299                                              size, buf, &eaten);
 300         }
 301
 302         if (!object)
 303                 die("Could not read blob %s", oid_to_hex(oid));
 304
 305         mark_next_object(object);
 306
 307         printf("blob\nmark :%"PRIu32"\n", last_idnum);
 308         if (show_original_ids)
 309                 printf("original-oid %s\n", oid_to_hex(oid));
 310         printf("data %"PRIuMAX"\n", (uintmax_t)size);
 311         if (size && fwrite(buf, size, 1, stdout) != 1)
 312                 die_errno("could not write blob '%s'", oid_to_hex(oid));
 313         printf("\n");
 314
 315         show_progress();
 316
 317         object->flags |= SHOWN;
 318         if (!eaten)
 319                 free(buf);
 320 }
 321
 322 static int depth_first(const void *a_, const void *b_)
 323 {
 324         const struct diff_filepair *a = *((const struct diff_filepair **)a_);
 325         const struct diff_filepair *b = *((const struct diff_filepair **)b_);
 326         const char *name_a, *name_b;
 327         int len_a, len_b, len;
 328         int cmp;
 329
 330         name_a = a->one ? a->one->path : a->two->path;
 331         name_b = b->one ? b->one->path : b->two->path;
 332
 333         len_a = strlen(name_a);
 334         len_b = strlen(name_b);
 335         len = (len_a < len_b) ? len_a : len_b;
 336
 337         /* strcmp will sort 'd' before 'd/e', we want 'd/e' before 'd' */
 338         cmp = memcmp(name_a, name_b, len);
 339         if (cmp)
 340                 return cmp;
 341         cmp = len_b - len_a;
 342         if (cmp)
 343                 return cmp;
 344         /*
 345          * Move 'R'ename entries last so that all references of the file
 346          * appear in the output before it is renamed (e.g., when a file
 347          * was copied and renamed in the same commit).
 348          */
 349         return (a->status == 'R') - (b->status == 'R');
 350 }
 351
 352 static void print_path_1(const char *path)
 353 {
 354         int need_quote = quote_c_style(path, NULL, NULL, 0);
 355         if (need_quote)
 356                 quote_c_style(path, NULL, stdout, 0);
 357         else if (strchr(path, ' '))
 358                 printf("\"%s\"", path);
 359         else
 360                 printf("%s", path);
 361 }
 362
 363 static void *anonymize_path_component(const void *path, size_t *len)
 364 {
 365         static int counter;
 366         struct strbuf out = STRBUF_INIT;
 367         strbuf_addf(&out, "path%d", counter++);
 368         return strbuf_detach(&out, len);
 369 }
 370
 371 static void print_path(const char *path)
 372 {
 373         if (!anonymize)
 374                 print_path_1(path);
 375         else {
 376                 static struct hashmap paths;
 377                 static struct strbuf anon = STRBUF_INIT;
 378
 379                 anonymize_path(&anon, path, &paths, anonymize_path_component);
 380                 print_path_1(anon.buf);
 381                 strbuf_reset(&anon);
 382         }
 383 }
 384
 385 static void *generate_fake_oid(const void *old, size_t *len)
 386 {
 387         static uint32_t counter = 1; /* avoid null oid */
 388         const unsigned hashsz = the_hash_algo->rawsz;
 389         unsigned char *out = xcalloc(hashsz, 1);
 390         put_be32(out + hashsz - 4, counter++);
 391         return out;
 392 }
 393
 394 static const struct object_id *anonymize_oid(const struct object_id *oid)
 395 {
 396         static struct hashmap objs;
 397         size_t len = the_hash_algo->rawsz;
 398         return anonymize_mem(&objs, generate_fake_oid, oid, &len);
 399 }
 400
 401 static void show_filemodify(struct diff_queue_struct *q,
 402                             struct diff_options *options, void *data)
 403 {
 404         int i;
 405         struct string_list *changed = data;
 406
 407         /*
 408          * Handle files below a directory first, in case they are all deleted
 409          * and the directory changes to a file or symlink.
 410          */
 411         QSORT(q->queue, q->nr, depth_first);
 412
 413         for (i = 0; i < q->nr; i++) {
 414                 struct diff_filespec *ospec = q->queue[i]->one;
 415                 struct diff_filespec *spec = q->queue[i]->two;
 416
 417                 switch (q->queue[i]->status) {
 418                 case DIFF_STATUS_DELETED:
 419                         printf("D ");
 420                         print_path(spec->path);
 421                         string_list_insert(changed, spec->path);
 422                         putchar('\n');
 423                         break;
 424
 425                 case DIFF_STATUS_COPIED:
 426                 case DIFF_STATUS_RENAMED:
 427                         /*
 428                          * If a change in the file corresponding to ospec->path
 429                          * has been observed, we cannot trust its contents
 430                          * because the diff is calculated based on the prior
 431                          * contents, not the current contents.  So, declare a
 432                          * copy or rename only if there was no change observed.
 433                          */
 434                         if (!string_list_has_string(changed, ospec->path)) {
 435                                 printf("%c ", q->queue[i]->status);
 436                                 print_path(ospec->path);
 437                                 putchar(' ');
 438                                 print_path(spec->path);
 439                                 string_list_insert(changed, spec->path);
 440                                 putchar('\n');
 441
 442                                 if (oideq(&ospec->oid, &spec->oid) &&
 443                                     ospec->mode == spec->mode)
 444                                         break;
 445                         }
 446                         /* fallthrough */
 447
 448                 case DIFF_STATUS_TYPE_CHANGED:
 449                 case DIFF_STATUS_MODIFIED:
 450                 case DIFF_STATUS_ADDED:
 451                         /*
 452                          * Links refer to objects in another repositories;
 453                          * output the SHA-1 verbatim.
 454                          */
 455                         if (no_data || S_ISGITLINK(spec->mode))
 456                                 printf("M %06o %s ", spec->mode,
 457                                        oid_to_hex(anonymize ?
 458                                                   anonymize_oid(&spec->oid) :
 459                                                   &spec->oid));
 460                         else {
 461                                 struct object *object = lookup_object(the_repository,
 462                                                                       &spec->oid);
 463                                 printf("M %06o :%d ", spec->mode,
 464                                        get_object_mark(object));
 465                         }
 466                         print_path(spec->path);
 467                         string_list_insert(changed, spec->path);
 468                         putchar('\n');
 469                         break;
 470
 471                 default:
 472                         die("Unexpected comparison status '%c' for %s, %s",
 473                                 q->queue[i]->status,
 474                                 ospec->path ? ospec->path : "none",
 475                                 spec->path ? spec->path : "none");
 476                 }
 477         }
 478 }
 479
 480 static const char *find_encoding(const char *begin, const char *end)
 481 {
 482         const char *needle = "\nencoding ";
 483         char *bol, *eol;
 484
 485         bol = memmem(begin, end ? end - begin : strlen(begin),
 486                      needle, strlen(needle));
 487         if (!bol)
 488                 return NULL;
 489         bol += strlen(needle);
 490         eol = strchrnul(bol, '\n');
 491         *eol = '\0';
 492         return bol;
 493 }
 494
 495 static void *anonymize_ref_component(const void *old, size_t *len)
 496 {
 497         static int counter;
 498         struct strbuf out = STRBUF_INIT;
 499         strbuf_addf(&out, "ref%d", counter++);
 500         return strbuf_detach(&out, len);
 501 }
 502
 503 static const char *anonymize_refname(const char *refname)
 504 {
 505         /*
 506          * If any of these prefixes is found, we will leave it intact
 507          * so that tags remain tags and so forth.
 508          */
 509         static const char *prefixes[] = {
 510                 "refs/heads/",
 511                 "refs/tags/",
 512                 "refs/remotes/",
 513                 "refs/"
 514         };
 515         static struct hashmap refs;
 516         static struct strbuf anon = STRBUF_INIT;
 517         int i;
 518
 519         /*
 520          * We also leave "master" as a special case, since it does not reveal
 521          * anything interesting.
 522          */
 523         if (!strcmp(refname, "refs/heads/master"))
 524                 return refname;
 525
 526         strbuf_reset(&anon);
 527         for (i = 0; i < ARRAY_SIZE(prefixes); i++) {
 528                 if (skip_prefix(refname, prefixes[i], &refname)) {
 529                         strbuf_addstr(&anon, prefixes[i]);
 530                         break;
 531                 }
 532         }
 533
 534         anonymize_path(&anon, refname, &refs, anonymize_ref_component);
 535         return anon.buf;
 536 }
 537
 538 /*
 539  * We do not even bother to cache commit messages, as they are unlikely
 540  * to be repeated verbatim, and it is not that interesting when they are.
 541  */
 542 static char *anonymize_commit_message(const char *old)
 543 {
 544         static int counter;
 545         return xstrfmt("subject %d\n\nbody\n", counter++);
 546 }
 547
 548 static struct hashmap idents;
 549 static void *anonymize_ident(const void *old, size_t *len)
 550 {
 551         static int counter;
 552         struct strbuf out = STRBUF_INIT;
 553         strbuf_addf(&out, "User %d <user%d@example.com>", counter, counter);
 554         counter++;
 555         return strbuf_detach(&out, len);
 556 }
 557
 558 /*
 559  * Our strategy here is to anonymize the names and email addresses,
 560  * but keep timestamps intact, as they influence things like traversal
 561  * order (and by themselves should not be too revealing).
 562  */
 563 static void anonymize_ident_line(const char **beg, const char **end)
 564 {
 565         static struct strbuf buffers[] = { STRBUF_INIT, STRBUF_INIT };
 566         static unsigned which_buffer;
 567
 568         struct strbuf *out;
 569         struct ident_split split;
 570         const char *end_of_header;
 571
 572         out = &buffers[which_buffer++];
 573         which_buffer %= ARRAY_SIZE(buffers);
 574         strbuf_reset(out);
 575
 576         /* skip "committer", "author", "tagger", etc */
 577         end_of_header = strchr(*beg, ' ');
 578         if (!end_of_header)
 579                 BUG("malformed line fed to anonymize_ident_line: %.*s",
 580                     (int)(*end - *beg), *beg);
 581         end_of_header++;
 582         strbuf_add(out, *beg, end_of_header - *beg);
 583
 584         if (!split_ident_line(&split, end_of_header, *end - end_of_header) &&
 585             split.date_begin) {
 586                 const char *ident;
 587                 size_t len;
 588
 589                 len = split.mail_end - split.name_begin;
 590                 ident = anonymize_mem(&idents, anonymize_ident,
 591                                       split.name_begin, &len);
 592                 strbuf_add(out, ident, len);
 593                 strbuf_addch(out, ' ');
 594                 strbuf_add(out, split.date_begin, split.tz_end - split.date_begin);
 595         } else {
 596                 strbuf_addstr(out, "Malformed Ident <malformed@example.com> 0 -0000");
 597         }
 598
 599         *beg = out->buf;
 600         *end = out->buf + out->len;
 601 }
 602
 603 static void handle_commit(struct commit *commit, struct rev_info *rev,
 604                           struct string_list *paths_of_changed_objects)
 605 {
 606         int saved_output_format = rev->diffopt.output_format;
 607         const char *commit_buffer;
 608         const char *author, *author_end, *committer, *committer_end;
 609         const char *encoding, *message;
 610         char *reencoded = NULL;
 611         struct commit_list *p;
 612         const char *refname;
 613         int i;
 614
 615         rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
 616
 617         parse_commit_or_die(commit);
 618         commit_buffer = get_commit_buffer(commit, NULL);
 619         author = strstr(commit_buffer, "\nauthor ");
 620         if (!author)
 621                 die("could not find author in commit %s",
 622                     oid_to_hex(&commit->object.oid));
 623         author++;
 624         author_end = strchrnul(author, '\n');
 625         committer = strstr(author_end, "\ncommitter ");
 626         if (!committer)
 627                 die("could not find committer in commit %s",
 628                     oid_to_hex(&commit->object.oid));
 629         committer++;
 630         committer_end = strchrnul(committer, '\n');
 631         message = strstr(committer_end, "\n\n");
 632         encoding = find_encoding(committer_end, message);
 633         if (message)
 634                 message += 2;
 635
 636         if (commit->parents &&
 637             (get_object_mark(&commit->parents->item->object) != 0 ||
 638              reference_excluded_commits) &&
 639             !full_tree) {
 640                 parse_commit_or_die(commit->parents->item);
 641                 diff_tree_oid(get_commit_tree_oid(commit->parents->item),
 642                               get_commit_tree_oid(commit), "", &rev->diffopt);
 643         }
 644         else
 645                 diff_root_tree_oid(get_commit_tree_oid(commit),
 646                                    "", &rev->diffopt);
 647
 648         /* Export the referenced blobs, and remember the marks. */
 649         for (i = 0; i < diff_queued_diff.nr; i++)
 650                 if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
 651                         export_blob(&diff_queued_diff.queue[i]->two->oid);
 652
 653         refname = *revision_sources_at(&revision_sources, commit);
 654         /*
 655          * FIXME: string_list_remove() below for each ref is overall
 656          * O(N^2).  Compared to a history walk and diffing trees, this is
 657          * just lost in the noise in practice.  However, theoretically a
 658          * repo may have enough refs for this to become slow.
 659          */
 660         string_list_remove(&extra_refs, refname, 0);
 661         if (anonymize) {
 662                 refname = anonymize_refname(refname);
 663                 anonymize_ident_line(&committer, &committer_end);
 664                 anonymize_ident_line(&author, &author_end);
 665         }
 666
 667         mark_next_object(&commit->object);
 668         if (anonymize) {
 669                 reencoded = anonymize_commit_message(message);
 670         } else if (encoding) {
 671                 switch(reencode_mode) {
 672                 case REENCODE_YES:
 673                         reencoded = reencode_string(message, "UTF-8", encoding);
 674                         break;
 675                 case REENCODE_NO:
 676                         break;
 677                 case REENCODE_ABORT:
 678                         die("Encountered commit-specific encoding %s in commit "
 679                             "%s; use --reencode=[yes|no] to handle it",
 680                             encoding, oid_to_hex(&commit->object.oid));
 681                 }
 682         }
 683         if (!commit->parents)
 684                 printf("reset %s\n", refname);
 685         printf("commit %s\nmark :%"PRIu32"\n", refname, last_idnum);
 686         if (show_original_ids)
 687                 printf("original-oid %s\n", oid_to_hex(&commit->object.oid));
 688         printf("%.*s\n%.*s\n",
 689                (int)(author_end - author), author,
 690                (int)(committer_end - committer), committer);
 691         if (!reencoded && encoding)
 692                 printf("encoding %s\n", encoding);
 693         printf("data %u\n%s",
 694                (unsigned)(reencoded
 695                           ? strlen(reencoded) : message
 696                           ? strlen(message) : 0),
 697                reencoded ? reencoded : message ? message : "");
 698         free(reencoded);
 699         unuse_commit_buffer(commit, commit_buffer);
 700
 701         for (i = 0, p = commit->parents; p; p = p->next) {
 702                 struct object *obj = &p->item->object;
 703                 int mark = get_object_mark(obj);
 704
 705                 if (!mark && !reference_excluded_commits)
 706                         continue;
 707                 if (i == 0)
 708                         printf("from ");
 709                 else
 710                         printf("merge ");
 711                 if (mark)
 712                         printf(":%d\n", mark);
 713                 else
 714                         printf("%s\n", oid_to_hex(anonymize ?
 715                                                   anonymize_oid(&obj->oid) :
 716                                                   &obj->oid));
 717                 i++;
 718         }
 719
 720         if (full_tree)
 721                 printf("deleteall\n");
 722         log_tree_diff_flush(rev);
 723         string_list_clear(paths_of_changed_objects, 0);
 724         rev->diffopt.output_format = saved_output_format;
 725
 726         printf("\n");
 727
 728         show_progress();
 729 }
 730
 731 static void *anonymize_tag(const void *old, size_t *len)
 732 {
 733         static int counter;
 734         struct strbuf out = STRBUF_INIT;
 735         strbuf_addf(&out, "tag message %d", counter++);
 736         return strbuf_detach(&out, len);
 737 }
 738
 739 static void handle_tail(struct object_array *commits, struct rev_info *revs,
 740                         struct string_list *paths_of_changed_objects)
 741 {
 742         struct commit *commit;
 743         while (commits->nr) {
 744                 commit = (struct commit *)object_array_pop(commits);
 745                 if (has_unshown_parent(commit)) {
 746                         /* Queue again, to be handled later */
 747                         add_object_array(&commit->object, NULL, commits);
 748                         return;
 749                 }
 750                 handle_commit(commit, revs, paths_of_changed_objects);
 751         }
 752 }
 753
 754 static void handle_tag(const char *name, struct tag *tag)
 755 {
 756         unsigned long size;
 757         enum object_type type;
 758         char *buf;
 759         const char *tagger, *tagger_end, *message;
 760         size_t message_size = 0;
 761         struct object *tagged;
 762         int tagged_mark;
 763         struct commit *p;
 764
 765         /* Trees have no identifier in fast-export output, thus we have no way
 766          * to output tags of trees, tags of tags of trees, etc.  Simply omit
 767          * such tags.
 768          */
 769         tagged = tag->tagged;
 770         while (tagged->type == OBJ_TAG) {
 771                 tagged = ((struct tag *)tagged)->tagged;
 772         }
 773         if (tagged->type == OBJ_TREE) {
 774                 warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
 775                         oid_to_hex(&tag->object.oid));
 776                 return;
 777         }
 778
 779         buf = read_object_file(&tag->object.oid, &type, &size);
 780         if (!buf)
 781                 die("could not read tag %s", oid_to_hex(&tag->object.oid));
 782         message = memmem(buf, size, "\n\n", 2);
 783         if (message) {
 784                 message += 2;
 785                 message_size = strlen(message);
 786         }
 787         tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
 788         if (!tagger) {
 789                 if (fake_missing_tagger)
 790                         tagger = "tagger Unspecified Tagger "
 791                                 "<unspecified-tagger> 0 +0000";
 792                 else
 793                         tagger = "";
 794                 tagger_end = tagger + strlen(tagger);
 795         } else {
 796                 tagger++;
 797                 tagger_end = strchrnul(tagger, '\n');
 798                 if (anonymize)
 799                         anonymize_ident_line(&tagger, &tagger_end);
 800         }
 801
 802         if (anonymize) {
 803                 name = anonymize_refname(name);
 804                 if (message) {
 805                         static struct hashmap tags;
 806                         message = anonymize_mem(&tags, anonymize_tag,
 807                                                 message, &message_size);
 808                 }
 809         }
 810
 811         /* handle signed tags */
 812         if (message) {
 813                 const char *signature = strstr(message,
 814                                                "\n-----BEGIN PGP SIGNATURE-----\n");
 815                 if (signature)
 816                         switch(signed_tag_mode) {
 817                         case SIGNED_TAG_ABORT:
 818                                 die("encountered signed tag %s; use "
 819                                     "--signed-tags=<mode> to handle it",
 820                                     oid_to_hex(&tag->object.oid));
 821                         case WARN:
 822                                 warning("exporting signed tag %s",
 823                                         oid_to_hex(&tag->object.oid));
 824                                 /* fallthru */
 825                         case VERBATIM:
 826                                 break;
 827                         case WARN_STRIP:
 828                                 warning("stripping signature from tag %s",
 829                                         oid_to_hex(&tag->object.oid));
 830                                 /* fallthru */
 831                         case STRIP:
 832                                 message_size = signature + 1 - message;
 833                                 break;
 834                         }
 835         }
 836
 837         /* handle tag->tagged having been filtered out due to paths specified */
 838         tagged = tag->tagged;
 839         tagged_mark = get_object_mark(tagged);
 840         if (!tagged_mark) {
 841                 switch(tag_of_filtered_mode) {
 842                 case TAG_FILTERING_ABORT:
 843                         die("tag %s tags unexported object; use "
 844                             "--tag-of-filtered-object=<mode> to handle it",
 845                             oid_to_hex(&tag->object.oid));
 846                 case DROP:
 847                         /* Ignore this tag altogether */
 848                         free(buf);
 849                         return;
 850                 case REWRITE:
 851                         if (tagged->type == OBJ_TAG && !mark_tags) {
 852                                 die(_("Error: Cannot export nested tags unless --mark-tags is specified."));
 853                         } else if (tagged->type == OBJ_COMMIT) {
 854                                 p = rewrite_commit((struct commit *)tagged);
 855                                 if (!p) {
 856                                         printf("reset %s\nfrom %s\n\n",
 857                                                name, oid_to_hex(&null_oid));
 858                                         free(buf);
 859                                         return;
 860                                 }
 861                                 tagged_mark = get_object_mark(&p->object);
 862                         } else {
 863                                 /* tagged->type is either OBJ_BLOB or OBJ_TAG */
 864                                 tagged_mark = get_object_mark(tagged);
 865                         }
 866                 }
 867         }
 868
 869         if (tagged->type == OBJ_TAG) {
 870                 printf("reset %s\nfrom %s\n\n",
 871                        name, oid_to_hex(&null_oid));
 872         }
 873         skip_prefix(name, "refs/tags/", &name);
 874         printf("tag %s\n", name);
 875         if (mark_tags) {
 876                 mark_next_object(&tag->object);
 877                 printf("mark :%"PRIu32"\n", last_idnum);
 878         }
 879         if (tagged_mark)
 880                 printf("from :%d\n", tagged_mark);
 881         else
 882                 printf("from %s\n", oid_to_hex(&tagged->oid));
 883
 884         if (show_original_ids)
 885                 printf("original-oid %s\n", oid_to_hex(&tag->object.oid));
 886         printf("%.*s%sdata %d\n%.*s\n",
 887                (int)(tagger_end - tagger), tagger,
 888                tagger == tagger_end ? "" : "\n",
 889                (int)message_size, (int)message_size, message ? message : "");
 890         free(buf);
 891 }
 892
 893 static struct commit *get_commit(struct rev_cmdline_entry *e, char *full_name)
 894 {
 895         switch (e->item->type) {
 896         case OBJ_COMMIT:
 897                 return (struct commit *)e->item;
 898         case OBJ_TAG: {
 899                 struct tag *tag = (struct tag *)e->item;
 900
 901                 /* handle nested tags */
 902                 while (tag && tag->object.type == OBJ_TAG) {
 903                         parse_object(the_repository, &tag->object.oid);
 904                         string_list_append(&tag_refs, full_name)->util = tag;
 905                         tag = (struct tag *)tag->tagged;
 906                 }
 907                 if (!tag)
 908                         die("Tag %s points nowhere?", e->name);
 909                 return (struct commit *)tag;
 910                 break;
 911         }
 912         default:
 913                 return NULL;
 914         }
 915 }
 916
 917 static void get_tags_and_duplicates(struct rev_cmdline_info *info)
 918 {
 919         int i;
 920
 921         for (i = 0; i < info->nr; i++) {
 922                 struct rev_cmdline_entry *e = info->rev + i;
 923                 struct object_id oid;
 924                 struct commit *commit;
 925                 char *full_name;
 926
 927                 if (e->flags & UNINTERESTING)
 928                         continue;
 929
 930                 if (dwim_ref(e->name, strlen(e->name), &oid, &full_name) != 1)
 931                         continue;
 932
 933                 if (refspecs.nr) {
 934                         char *private;
 935                         private = apply_refspecs(&refspecs, full_name);
 936                         if (private) {
 937                                 free(full_name);
 938                                 full_name = private;
 939                         }
 940                 }
 941
 942                 commit = get_commit(e, full_name);
 943                 if (!commit) {
 944                         warning("%s: Unexpected object of type %s, skipping.",
 945                                 e->name,
 946                                 type_name(e->item->type));
 947                         continue;
 948                 }
 949
 950                 switch(commit->object.type) {
 951                 case OBJ_COMMIT:
 952                         break;
 953                 case OBJ_BLOB:
 954                         export_blob(&commit->object.oid);
 955                         continue;
 956                 default: /* OBJ_TAG (nested tags) is already handled */
 957                         warning("Tag points to object of unexpected type %s, skipping.",
 958                                 type_name(commit->object.type));
 959                         continue;
 960                 }
 961
 962                 /*
 963                  * Make sure this ref gets properly updated eventually, whether
 964                  * through a commit or manually at the end.
 965                  */
 966                 if (e->item->type != OBJ_TAG)
 967                         string_list_append(&extra_refs, full_name)->util = commit;
 968
 969                 if (!*revision_sources_at(&revision_sources, commit))
 970                         *revision_sources_at(&revision_sources, commit) = full_name;
 971         }
 972
 973         string_list_sort(&extra_refs);
 974         string_list_remove_duplicates(&extra_refs, 0);
 975 }
 976
 977 static void handle_tags_and_duplicates(struct string_list *extras)
 978 {
 979         struct commit *commit;
 980         int i;
 981
 982         for (i = extras->nr - 1; i >= 0; i--) {
 983                 const char *name = extras->items[i].string;
 984                 struct object *object = extras->items[i].util;
 985                 int mark;
 986
 987                 switch (object->type) {
 988                 case OBJ_TAG:
 989                         handle_tag(name, (struct tag *)object);
 990                         break;
 991                 case OBJ_COMMIT:
 992                         if (anonymize)
 993                                 name = anonymize_refname(name);
 994                         /* create refs pointing to already seen commits */
 995                         commit = rewrite_commit((struct commit *)object);
 996                         if (!commit) {
 997                                 /*
 998                                  * Neither this object nor any of its
 999                                  * ancestors touch any relevant paths, so
1000                                  * it has been filtered to nothing.  Delete
1001                                  * it.
1002                                  */
1003                                 printf("reset %s\nfrom %s\n\n",
1004                                        name, oid_to_hex(&null_oid));
1005                                 continue;
1006                         }
1007
1008                         mark = get_object_mark(&commit->object);
1009                         if (!mark) {
1010                                 /*
1011                                  * Getting here means we have a commit which
1012                                  * was excluded by a negative refspec (e.g.
1013                                  * fast-export ^master master).  If we are
1014                                  * referencing excluded commits, set the ref
1015                                  * to the exact commit.  Otherwise, the user
1016                                  * wants the branch exported but every commit
1017                                  * in its history to be deleted, which basically
1018                                  * just means deletion of the ref.
1019                                  */
1020                                 if (!reference_excluded_commits) {
1021                                         /* delete the ref */
1022                                         printf("reset %s\nfrom %s\n\n",
1023                                                name, oid_to_hex(&null_oid));
1024                                         continue;
1025                                 }
1026                                 /* set ref to commit using oid, not mark */
1027                                 printf("reset %s\nfrom %s\n\n", name,
1028                                        oid_to_hex(&commit->object.oid));
1029                                 continue;
1030                         }
1031
1032                         printf("reset %s\nfrom :%d\n\n", name, mark
1033                                );
1034                         show_progress();
1035                         break;
1036                 }
1037         }
1038 }
1039
1040 static void export_marks(char *file)
1041 {
1042         unsigned int i;
1043         uint32_t mark;
1044         struct decoration_entry *deco = idnums.entries;
1045         FILE *f;
1046         int e = 0;
1047
1048         f = fopen_for_writing(file);
1049         if (!f)
1050                 die_errno("Unable to open marks file %s for writing.", file);
1051
1052         for (i = 0; i < idnums.size; i++) {
1053                 if (deco->base && deco->base->type == 1) {
1054                         mark = ptr_to_mark(deco->decoration);
1055                         if (fprintf(f, ":%"PRIu32" %s\n", mark,
1056                                 oid_to_hex(&deco->base->oid)) < 0) {
1057                             e = 1;
1058                             break;
1059                         }
1060                 }
1061                 deco++;
1062         }
1063
1064         e |= ferror(f);
1065         e |= fclose(f);
1066         if (e)
1067                 error("Unable to write marks file %s.", file);
1068 }
1069
1070 static void import_marks(char *input_file, int check_exists)
1071 {
1072         char line[512];
1073         FILE *f;
1074         struct stat sb;
1075
1076         if (check_exists && stat(input_file, &sb))
1077                 return;
1078
1079         f = xfopen(input_file, "r");
1080         while (fgets(line, sizeof(line), f)) {
1081                 uint32_t mark;
1082                 char *line_end, *mark_end;
1083                 struct object_id oid;
1084                 struct object *object;
1085                 struct commit *commit;
1086                 enum object_type type;
1087
1088                 line_end = strchr(line, '\n');
1089                 if (line[0] != ':' || !line_end)
1090                         die("corrupt mark line: %s", line);
1091                 *line_end = '\0';
1092
1093                 mark = strtoumax(line + 1, &mark_end, 10);
1094                 if (!mark || mark_end == line + 1
1095                         || *mark_end != ' ' || get_oid_hex(mark_end + 1, &oid))
1096                         die("corrupt mark line: %s", line);
1097
1098                 if (last_idnum < mark)
1099                         last_idnum = mark;
1100
1101                 type = oid_object_info(the_repository, &oid, NULL);
1102                 if (type < 0)
1103                         die("object not found: %s", oid_to_hex(&oid));
1104
1105                 if (type != OBJ_COMMIT)
1106                         /* only commits */
1107                         continue;
1108
1109                 commit = lookup_commit(the_repository, &oid);
1110                 if (!commit)
1111                         die("not a commit? can't happen: %s", oid_to_hex(&oid));
1112
1113                 object = &commit->object;
1114
1115                 if (object->flags & SHOWN)
1116                         error("Object %s already has a mark", oid_to_hex(&oid));
1117
1118                 mark_object(object, mark);
1119
1120                 object->flags |= SHOWN;
1121         }
1122         fclose(f);
1123 }
1124
1125 static void handle_deletes(void)
1126 {
1127         int i;
1128         for (i = 0; i < refspecs.nr; i++) {
1129                 struct refspec_item *refspec = &refspecs.items[i];
1130                 if (*refspec->src)
1131                         continue;
1132
1133                 printf("reset %s\nfrom %s\n\n",
1134                                 refspec->dst, oid_to_hex(&null_oid));
1135         }
1136 }
1137
1138 int cmd_fast_export(int argc, const char **argv, const char *prefix)
1139 {
1140         struct rev_info revs;
1141         struct object_array commits = OBJECT_ARRAY_INIT;
1142         struct commit *commit;
1143         char *export_filename = NULL,
1144              *import_filename = NULL,
1145              *import_filename_if_exists = NULL;
1146         uint32_t lastimportid;
1147         struct string_list refspecs_list = STRING_LIST_INIT_NODUP;
1148         struct string_list paths_of_changed_objects = STRING_LIST_INIT_DUP;
1149         struct option options[] = {
1150                 OPT_INTEGER(0, "progress", &progress,
1151                             N_("show progress after <n> objects")),
1152                 OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, N_("mode"),
1153                              N_("select handling of signed tags"),
1154                              parse_opt_signed_tag_mode),
1155                 OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, N_("mode"),
1156                              N_("select handling of tags that tag filtered objects"),
1157                              parse_opt_tag_of_filtered_mode),
1158                 OPT_CALLBACK(0, "reencode", &reencode_mode, N_("mode"),
1159                              N_("select handling of commit messages in an alternate encoding"),
1160                              parse_opt_reencode_mode),
1161                 OPT_STRING(0, "export-marks", &export_filename, N_("file"),
1162                              N_("Dump marks to this file")),
1163                 OPT_STRING(0, "import-marks", &import_filename, N_("file"),
1164                              N_("Import marks from this file")),
1165                 OPT_STRING(0, "import-marks-if-exists",
1166                              &import_filename_if_exists,
1167                              N_("file"),
1168                              N_("Import marks from this file if it exists")),
1169                 OPT_BOOL(0, "fake-missing-tagger", &fake_missing_tagger,
1170                          N_("Fake a tagger when tags lack one")),
1171                 OPT_BOOL(0, "full-tree", &full_tree,
1172                          N_("Output full tree for each commit")),
1173                 OPT_BOOL(0, "use-done-feature", &use_done_feature,
1174                              N_("Use the done feature to terminate the stream")),
1175                 OPT_BOOL(0, "no-data", &no_data, N_("Skip output of blob data")),
1176                 OPT_STRING_LIST(0, "refspec", &refspecs_list, N_("refspec"),
1177                              N_("Apply refspec to exported refs")),
1178                 OPT_BOOL(0, "anonymize", &anonymize, N_("anonymize output")),
1179                 OPT_BOOL(0, "reference-excluded-parents",
1180                          &reference_excluded_commits, N_("Reference parents which are not in fast-export stream by object id")),
1181                 OPT_BOOL(0, "show-original-ids", &show_original_ids,
1182                             N_("Show original object ids of blobs/commits")),
1183                 OPT_BOOL(0, "mark-tags", &mark_tags,
1184                             N_("Label tags with mark ids")),
1185
1186                 OPT_END()
1187         };
1188
1189         if (argc == 1)
1190                 usage_with_options (fast_export_usage, options);
1191
1192         /* we handle encodings */
1193         git_config(git_default_config, NULL);
1194
1195         repo_init_revisions(the_repository, &revs, prefix);
1196         init_revision_sources(&revision_sources);
1197         revs.topo_order = 1;
1198         revs.sources = &revision_sources;
1199         revs.rewrite_parents = 1;
1200         argc = parse_options(argc, argv, prefix, options, fast_export_usage,
1201                         PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN);
1202         argc = setup_revisions(argc, argv, &revs, NULL);
1203         if (argc > 1)
1204                 usage_with_options (fast_export_usage, options);
1205
1206         if (refspecs_list.nr) {
1207                 int i;
1208
1209                 for (i = 0; i < refspecs_list.nr; i++)
1210                         refspec_append(&refspecs, refspecs_list.items[i].string);
1211
1212                 string_list_clear(&refspecs_list, 1);
1213         }
1214
1215         if (use_done_feature)
1216                 printf("feature done\n");
1217
1218         if (import_filename && import_filename_if_exists)
1219                 die(_("Cannot pass both --import-marks and --import-marks-if-exists"));
1220         if (import_filename)
1221                 import_marks(import_filename, 0);
1222         else if (import_filename_if_exists)
1223                 import_marks(import_filename_if_exists, 1);
1224         lastimportid = last_idnum;
1225
1226         if (import_filename && revs.prune_data.nr)
1227                 full_tree = 1;
1228
1229         get_tags_and_duplicates(&revs.cmdline);
1230
1231         if (prepare_revision_walk(&revs))
1232                 die("revision walk setup failed");
1233         revs.diffopt.format_callback = show_filemodify;
1234         revs.diffopt.format_callback_data = &paths_of_changed_objects;
1235         revs.diffopt.flags.recursive = 1;
1236         while ((commit = get_revision(&revs))) {
1237                 if (has_unshown_parent(commit)) {
1238                         add_object_array(&commit->object, NULL, &commits);
1239                 }
1240                 else {
1241                         handle_commit(commit, &revs, &paths_of_changed_objects);
1242                         handle_tail(&commits, &revs, &paths_of_changed_objects);
1243                 }
1244         }
1245
1246         handle_tags_and_duplicates(&extra_refs);
1247         handle_tags_and_duplicates(&tag_refs);
1248         handle_deletes();
1249
1250         if (export_filename && lastimportid != last_idnum)
1251                 export_marks(export_filename);
1252
1253         if (use_done_feature)
1254                 printf("done\n");
1255
1256         refspec_clear(&refspecs);
1257
1258         return 0;
1259 }