builtin / fast-export.con commit Merge branch 'jk/colors' (3dadfc7)
   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 "commit.h"
   9#include "object.h"
  10#include "tag.h"
  11#include "diff.h"
  12#include "diffcore.h"
  13#include "log-tree.h"
  14#include "revision.h"
  15#include "decorate.h"
  16#include "string-list.h"
  17#include "utf8.h"
  18#include "parse-options.h"
  19#include "quote.h"
  20#include "remote.h"
  21#include "blob.h"
  22
  23static const char *fast_export_usage[] = {
  24        N_("git fast-export [rev-list-opts]"),
  25        NULL
  26};
  27
  28static int progress;
  29static enum { ABORT, VERBATIM, WARN, WARN_STRIP, STRIP } signed_tag_mode = ABORT;
  30static enum { ERROR, DROP, REWRITE } tag_of_filtered_mode = ERROR;
  31static int fake_missing_tagger;
  32static int use_done_feature;
  33static int no_data;
  34static int full_tree;
  35static struct string_list extra_refs = STRING_LIST_INIT_NODUP;
  36static struct refspec *refspecs;
  37static int refspecs_nr;
  38static int anonymize;
  39
  40static int parse_opt_signed_tag_mode(const struct option *opt,
  41                                     const char *arg, int unset)
  42{
  43        if (unset || !strcmp(arg, "abort"))
  44                signed_tag_mode = ABORT;
  45        else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
  46                signed_tag_mode = VERBATIM;
  47        else if (!strcmp(arg, "warn"))
  48                signed_tag_mode = WARN;
  49        else if (!strcmp(arg, "warn-strip"))
  50                signed_tag_mode = WARN_STRIP;
  51        else if (!strcmp(arg, "strip"))
  52                signed_tag_mode = STRIP;
  53        else
  54                return error("Unknown signed-tags mode: %s", arg);
  55        return 0;
  56}
  57
  58static int parse_opt_tag_of_filtered_mode(const struct option *opt,
  59                                          const char *arg, int unset)
  60{
  61        if (unset || !strcmp(arg, "abort"))
  62                tag_of_filtered_mode = ERROR;
  63        else if (!strcmp(arg, "drop"))
  64                tag_of_filtered_mode = DROP;
  65        else if (!strcmp(arg, "rewrite"))
  66                tag_of_filtered_mode = REWRITE;
  67        else
  68                return error("Unknown tag-of-filtered mode: %s", arg);
  69        return 0;
  70}
  71
  72static struct decoration idnums;
  73static uint32_t last_idnum;
  74
  75static int has_unshown_parent(struct commit *commit)
  76{
  77        struct commit_list *parent;
  78
  79        for (parent = commit->parents; parent; parent = parent->next)
  80                if (!(parent->item->object.flags & SHOWN) &&
  81                    !(parent->item->object.flags & UNINTERESTING))
  82                        return 1;
  83        return 0;
  84}
  85
  86struct anonymized_entry {
  87        struct hashmap_entry hash;
  88        const char *orig;
  89        size_t orig_len;
  90        const char *anon;
  91        size_t anon_len;
  92};
  93
  94static int anonymized_entry_cmp(const void *va, const void *vb,
  95                                const void *data)
  96{
  97        const struct anonymized_entry *a = va, *b = vb;
  98        return a->orig_len != b->orig_len ||
  99                memcmp(a->orig, b->orig, a->orig_len);
 100}
 101
 102/*
 103 * Basically keep a cache of X->Y so that we can repeatedly replace
 104 * the same anonymized string with another. The actual generation
 105 * is farmed out to the generate function.
 106 */
 107static const void *anonymize_mem(struct hashmap *map,
 108                                 void *(*generate)(const void *, size_t *),
 109                                 const void *orig, size_t *len)
 110{
 111        struct anonymized_entry key, *ret;
 112
 113        if (!map->cmpfn)
 114                hashmap_init(map, anonymized_entry_cmp, 0);
 115
 116        hashmap_entry_init(&key, memhash(orig, *len));
 117        key.orig = orig;
 118        key.orig_len = *len;
 119        ret = hashmap_get(map, &key, NULL);
 120
 121        if (!ret) {
 122                ret = xmalloc(sizeof(*ret));
 123                hashmap_entry_init(&ret->hash, key.hash.hash);
 124                ret->orig = xstrdup(orig);
 125                ret->orig_len = *len;
 126                ret->anon = generate(orig, len);
 127                ret->anon_len = *len;
 128                hashmap_put(map, ret);
 129        }
 130
 131        *len = ret->anon_len;
 132        return ret->anon;
 133}
 134
 135/*
 136 * We anonymize each component of a path individually,
 137 * so that paths a/b and a/c will share a common root.
 138 * The paths are cached via anonymize_mem so that repeated
 139 * lookups for "a" will yield the same value.
 140 */
 141static void anonymize_path(struct strbuf *out, const char *path,
 142                           struct hashmap *map,
 143                           void *(*generate)(const void *, size_t *))
 144{
 145        while (*path) {
 146                const char *end_of_component = strchrnul(path, '/');
 147                size_t len = end_of_component - path;
 148                const char *c = anonymize_mem(map, generate, path, &len);
 149                strbuf_add(out, c, len);
 150                path = end_of_component;
 151                if (*path)
 152                        strbuf_addch(out, *path++);
 153        }
 154}
 155
 156/* Since intptr_t is C99, we do not use it here */
 157static inline uint32_t *mark_to_ptr(uint32_t mark)
 158{
 159        return ((uint32_t *)NULL) + mark;
 160}
 161
 162static inline uint32_t ptr_to_mark(void * mark)
 163{
 164        return (uint32_t *)mark - (uint32_t *)NULL;
 165}
 166
 167static inline void mark_object(struct object *object, uint32_t mark)
 168{
 169        add_decoration(&idnums, object, mark_to_ptr(mark));
 170}
 171
 172static inline void mark_next_object(struct object *object)
 173{
 174        mark_object(object, ++last_idnum);
 175}
 176
 177static int get_object_mark(struct object *object)
 178{
 179        void *decoration = lookup_decoration(&idnums, object);
 180        if (!decoration)
 181                return 0;
 182        return ptr_to_mark(decoration);
 183}
 184
 185static void show_progress(void)
 186{
 187        static int counter = 0;
 188        if (!progress)
 189                return;
 190        if ((++counter % progress) == 0)
 191                printf("progress %d objects\n", counter);
 192}
 193
 194/*
 195 * Ideally we would want some transformation of the blob data here
 196 * that is unreversible, but would still be the same size and have
 197 * the same data relationship to other blobs (so that we get the same
 198 * delta and packing behavior as the original). But the first and last
 199 * requirements there are probably mutually exclusive, so let's take
 200 * the easy way out for now, and just generate arbitrary content.
 201 *
 202 * There's no need to cache this result with anonymize_mem, since
 203 * we already handle blob content caching with marks.
 204 */
 205static char *anonymize_blob(unsigned long *size)
 206{
 207        static int counter;
 208        struct strbuf out = STRBUF_INIT;
 209        strbuf_addf(&out, "anonymous blob %d", counter++);
 210        *size = out.len;
 211        return strbuf_detach(&out, NULL);
 212}
 213
 214static void export_blob(const unsigned char *sha1)
 215{
 216        unsigned long size;
 217        enum object_type type;
 218        char *buf;
 219        struct object *object;
 220        int eaten;
 221
 222        if (no_data)
 223                return;
 224
 225        if (is_null_sha1(sha1))
 226                return;
 227
 228        object = lookup_object(sha1);
 229        if (object && object->flags & SHOWN)
 230                return;
 231
 232        if (anonymize) {
 233                buf = anonymize_blob(&size);
 234                object = (struct object *)lookup_blob(sha1);
 235                eaten = 0;
 236        } else {
 237                buf = read_sha1_file(sha1, &type, &size);
 238                if (!buf)
 239                        die ("Could not read blob %s", sha1_to_hex(sha1));
 240                if (check_sha1_signature(sha1, buf, size, typename(type)) < 0)
 241                        die("sha1 mismatch in blob %s", sha1_to_hex(sha1));
 242                object = parse_object_buffer(sha1, type, size, buf, &eaten);
 243        }
 244
 245        if (!object)
 246                die("Could not read blob %s", sha1_to_hex(sha1));
 247
 248        mark_next_object(object);
 249
 250        printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
 251        if (size && fwrite(buf, size, 1, stdout) != 1)
 252                die_errno ("Could not write blob '%s'", sha1_to_hex(sha1));
 253        printf("\n");
 254
 255        show_progress();
 256
 257        object->flags |= SHOWN;
 258        if (!eaten)
 259                free(buf);
 260}
 261
 262static int depth_first(const void *a_, const void *b_)
 263{
 264        const struct diff_filepair *a = *((const struct diff_filepair **)a_);
 265        const struct diff_filepair *b = *((const struct diff_filepair **)b_);
 266        const char *name_a, *name_b;
 267        int len_a, len_b, len;
 268        int cmp;
 269
 270        name_a = a->one ? a->one->path : a->two->path;
 271        name_b = b->one ? b->one->path : b->two->path;
 272
 273        len_a = strlen(name_a);
 274        len_b = strlen(name_b);
 275        len = (len_a < len_b) ? len_a : len_b;
 276
 277        /* strcmp will sort 'd' before 'd/e', we want 'd/e' before 'd' */
 278        cmp = memcmp(name_a, name_b, len);
 279        if (cmp)
 280                return cmp;
 281        cmp = len_b - len_a;
 282        if (cmp)
 283                return cmp;
 284        /*
 285         * Move 'R'ename entries last so that all references of the file
 286         * appear in the output before it is renamed (e.g., when a file
 287         * was copied and renamed in the same commit).
 288         */
 289        return (a->status == 'R') - (b->status == 'R');
 290}
 291
 292static void print_path_1(const char *path)
 293{
 294        int need_quote = quote_c_style(path, NULL, NULL, 0);
 295        if (need_quote)
 296                quote_c_style(path, NULL, stdout, 0);
 297        else if (strchr(path, ' '))
 298                printf("\"%s\"", path);
 299        else
 300                printf("%s", path);
 301}
 302
 303static void *anonymize_path_component(const void *path, size_t *len)
 304{
 305        static int counter;
 306        struct strbuf out = STRBUF_INIT;
 307        strbuf_addf(&out, "path%d", counter++);
 308        return strbuf_detach(&out, len);
 309}
 310
 311static void print_path(const char *path)
 312{
 313        if (!anonymize)
 314                print_path_1(path);
 315        else {
 316                static struct hashmap paths;
 317                static struct strbuf anon = STRBUF_INIT;
 318
 319                anonymize_path(&anon, path, &paths, anonymize_path_component);
 320                print_path_1(anon.buf);
 321                strbuf_reset(&anon);
 322        }
 323}
 324
 325static void *generate_fake_sha1(const void *old, size_t *len)
 326{
 327        static uint32_t counter = 1; /* avoid null sha1 */
 328        unsigned char *out = xcalloc(20, 1);
 329        put_be32(out + 16, counter++);
 330        return out;
 331}
 332
 333static const unsigned char *anonymize_sha1(const unsigned char *sha1)
 334{
 335        static struct hashmap sha1s;
 336        size_t len = 20;
 337        return anonymize_mem(&sha1s, generate_fake_sha1, sha1, &len);
 338}
 339
 340static void show_filemodify(struct diff_queue_struct *q,
 341                            struct diff_options *options, void *data)
 342{
 343        int i;
 344
 345        /*
 346         * Handle files below a directory first, in case they are all deleted
 347         * and the directory changes to a file or symlink.
 348         */
 349        qsort(q->queue, q->nr, sizeof(q->queue[0]), depth_first);
 350
 351        for (i = 0; i < q->nr; i++) {
 352                struct diff_filespec *ospec = q->queue[i]->one;
 353                struct diff_filespec *spec = q->queue[i]->two;
 354
 355                switch (q->queue[i]->status) {
 356                case DIFF_STATUS_DELETED:
 357                        printf("D ");
 358                        print_path(spec->path);
 359                        putchar('\n');
 360                        break;
 361
 362                case DIFF_STATUS_COPIED:
 363                case DIFF_STATUS_RENAMED:
 364                        printf("%c ", q->queue[i]->status);
 365                        print_path(ospec->path);
 366                        putchar(' ');
 367                        print_path(spec->path);
 368                        putchar('\n');
 369
 370                        if (!hashcmp(ospec->sha1, spec->sha1) &&
 371                            ospec->mode == spec->mode)
 372                                break;
 373                        /* fallthrough */
 374
 375                case DIFF_STATUS_TYPE_CHANGED:
 376                case DIFF_STATUS_MODIFIED:
 377                case DIFF_STATUS_ADDED:
 378                        /*
 379                         * Links refer to objects in another repositories;
 380                         * output the SHA-1 verbatim.
 381                         */
 382                        if (no_data || S_ISGITLINK(spec->mode))
 383                                printf("M %06o %s ", spec->mode,
 384                                       sha1_to_hex(anonymize ?
 385                                                   anonymize_sha1(spec->sha1) :
 386                                                   spec->sha1));
 387                        else {
 388                                struct object *object = lookup_object(spec->sha1);
 389                                printf("M %06o :%d ", spec->mode,
 390                                       get_object_mark(object));
 391                        }
 392                        print_path(spec->path);
 393                        putchar('\n');
 394                        break;
 395
 396                default:
 397                        die("Unexpected comparison status '%c' for %s, %s",
 398                                q->queue[i]->status,
 399                                ospec->path ? ospec->path : "none",
 400                                spec->path ? spec->path : "none");
 401                }
 402        }
 403}
 404
 405static const char *find_encoding(const char *begin, const char *end)
 406{
 407        const char *needle = "\nencoding ";
 408        char *bol, *eol;
 409
 410        bol = memmem(begin, end ? end - begin : strlen(begin),
 411                     needle, strlen(needle));
 412        if (!bol)
 413                return git_commit_encoding;
 414        bol += strlen(needle);
 415        eol = strchrnul(bol, '\n');
 416        *eol = '\0';
 417        return bol;
 418}
 419
 420static void *anonymize_ref_component(const void *old, size_t *len)
 421{
 422        static int counter;
 423        struct strbuf out = STRBUF_INIT;
 424        strbuf_addf(&out, "ref%d", counter++);
 425        return strbuf_detach(&out, len);
 426}
 427
 428static const char *anonymize_refname(const char *refname)
 429{
 430        /*
 431         * If any of these prefixes is found, we will leave it intact
 432         * so that tags remain tags and so forth.
 433         */
 434        static const char *prefixes[] = {
 435                "refs/heads/",
 436                "refs/tags/",
 437                "refs/remotes/",
 438                "refs/"
 439        };
 440        static struct hashmap refs;
 441        static struct strbuf anon = STRBUF_INIT;
 442        int i;
 443
 444        /*
 445         * We also leave "master" as a special case, since it does not reveal
 446         * anything interesting.
 447         */
 448        if (!strcmp(refname, "refs/heads/master"))
 449                return refname;
 450
 451        strbuf_reset(&anon);
 452        for (i = 0; i < ARRAY_SIZE(prefixes); i++) {
 453                if (skip_prefix(refname, prefixes[i], &refname)) {
 454                        strbuf_addstr(&anon, prefixes[i]);
 455                        break;
 456                }
 457        }
 458
 459        anonymize_path(&anon, refname, &refs, anonymize_ref_component);
 460        return anon.buf;
 461}
 462
 463/*
 464 * We do not even bother to cache commit messages, as they are unlikely
 465 * to be repeated verbatim, and it is not that interesting when they are.
 466 */
 467static char *anonymize_commit_message(const char *old)
 468{
 469        static int counter;
 470        return xstrfmt("subject %d\n\nbody\n", counter++);
 471}
 472
 473static struct hashmap idents;
 474static void *anonymize_ident(const void *old, size_t *len)
 475{
 476        static int counter;
 477        struct strbuf out = STRBUF_INIT;
 478        strbuf_addf(&out, "User %d <user%d@example.com>", counter, counter);
 479        counter++;
 480        return strbuf_detach(&out, len);
 481}
 482
 483/*
 484 * Our strategy here is to anonymize the names and email addresses,
 485 * but keep timestamps intact, as they influence things like traversal
 486 * order (and by themselves should not be too revealing).
 487 */
 488static void anonymize_ident_line(const char **beg, const char **end)
 489{
 490        static struct strbuf buffers[] = { STRBUF_INIT, STRBUF_INIT };
 491        static unsigned which_buffer;
 492
 493        struct strbuf *out;
 494        struct ident_split split;
 495        const char *end_of_header;
 496
 497        out = &buffers[which_buffer++];
 498        which_buffer %= ARRAY_SIZE(buffers);
 499        strbuf_reset(out);
 500
 501        /* skip "committer", "author", "tagger", etc */
 502        end_of_header = strchr(*beg, ' ');
 503        if (!end_of_header)
 504                die("BUG: malformed line fed to anonymize_ident_line: %.*s",
 505                    (int)(*end - *beg), *beg);
 506        end_of_header++;
 507        strbuf_add(out, *beg, end_of_header - *beg);
 508
 509        if (!split_ident_line(&split, end_of_header, *end - end_of_header) &&
 510            split.date_begin) {
 511                const char *ident;
 512                size_t len;
 513
 514                len = split.mail_end - split.name_begin;
 515                ident = anonymize_mem(&idents, anonymize_ident,
 516                                      split.name_begin, &len);
 517                strbuf_add(out, ident, len);
 518                strbuf_addch(out, ' ');
 519                strbuf_add(out, split.date_begin, split.tz_end - split.date_begin);
 520        } else {
 521                strbuf_addstr(out, "Malformed Ident <malformed@example.com> 0 -0000");
 522        }
 523
 524        *beg = out->buf;
 525        *end = out->buf + out->len;
 526}
 527
 528static void handle_commit(struct commit *commit, struct rev_info *rev)
 529{
 530        int saved_output_format = rev->diffopt.output_format;
 531        const char *commit_buffer;
 532        const char *author, *author_end, *committer, *committer_end;
 533        const char *encoding, *message;
 534        char *reencoded = NULL;
 535        struct commit_list *p;
 536        const char *refname;
 537        int i;
 538
 539        rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
 540
 541        parse_commit_or_die(commit);
 542        commit_buffer = get_commit_buffer(commit, NULL);
 543        author = strstr(commit_buffer, "\nauthor ");
 544        if (!author)
 545                die ("Could not find author in commit %s",
 546                     sha1_to_hex(commit->object.sha1));
 547        author++;
 548        author_end = strchrnul(author, '\n');
 549        committer = strstr(author_end, "\ncommitter ");
 550        if (!committer)
 551                die ("Could not find committer in commit %s",
 552                     sha1_to_hex(commit->object.sha1));
 553        committer++;
 554        committer_end = strchrnul(committer, '\n');
 555        message = strstr(committer_end, "\n\n");
 556        encoding = find_encoding(committer_end, message);
 557        if (message)
 558                message += 2;
 559
 560        if (commit->parents &&
 561            get_object_mark(&commit->parents->item->object) != 0 &&
 562            !full_tree) {
 563                parse_commit_or_die(commit->parents->item);
 564                diff_tree_sha1(commit->parents->item->tree->object.sha1,
 565                               commit->tree->object.sha1, "", &rev->diffopt);
 566        }
 567        else
 568                diff_root_tree_sha1(commit->tree->object.sha1,
 569                                    "", &rev->diffopt);
 570
 571        /* Export the referenced blobs, and remember the marks. */
 572        for (i = 0; i < diff_queued_diff.nr; i++)
 573                if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
 574                        export_blob(diff_queued_diff.queue[i]->two->sha1);
 575
 576        refname = commit->util;
 577        if (anonymize) {
 578                refname = anonymize_refname(refname);
 579                anonymize_ident_line(&committer, &committer_end);
 580                anonymize_ident_line(&author, &author_end);
 581        }
 582
 583        mark_next_object(&commit->object);
 584        if (anonymize)
 585                reencoded = anonymize_commit_message(message);
 586        else if (!is_encoding_utf8(encoding))
 587                reencoded = reencode_string(message, "UTF-8", encoding);
 588        if (!commit->parents)
 589                printf("reset %s\n", refname);
 590        printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
 591               refname, last_idnum,
 592               (int)(author_end - author), author,
 593               (int)(committer_end - committer), committer,
 594               (unsigned)(reencoded
 595                          ? strlen(reencoded) : message
 596                          ? strlen(message) : 0),
 597               reencoded ? reencoded : message ? message : "");
 598        free(reencoded);
 599        unuse_commit_buffer(commit, commit_buffer);
 600
 601        for (i = 0, p = commit->parents; p; p = p->next) {
 602                int mark = get_object_mark(&p->item->object);
 603                if (!mark)
 604                        continue;
 605                if (i == 0)
 606                        printf("from :%d\n", mark);
 607                else
 608                        printf("merge :%d\n", mark);
 609                i++;
 610        }
 611
 612        if (full_tree)
 613                printf("deleteall\n");
 614        log_tree_diff_flush(rev);
 615        rev->diffopt.output_format = saved_output_format;
 616
 617        printf("\n");
 618
 619        show_progress();
 620}
 621
 622static void *anonymize_tag(const void *old, size_t *len)
 623{
 624        static int counter;
 625        struct strbuf out = STRBUF_INIT;
 626        strbuf_addf(&out, "tag message %d", counter++);
 627        return strbuf_detach(&out, len);
 628}
 629
 630static void handle_tail(struct object_array *commits, struct rev_info *revs)
 631{
 632        struct commit *commit;
 633        while (commits->nr) {
 634                commit = (struct commit *)commits->objects[commits->nr - 1].item;
 635                if (has_unshown_parent(commit))
 636                        return;
 637                handle_commit(commit, revs);
 638                commits->nr--;
 639        }
 640}
 641
 642static void handle_tag(const char *name, struct tag *tag)
 643{
 644        unsigned long size;
 645        enum object_type type;
 646        char *buf;
 647        const char *tagger, *tagger_end, *message;
 648        size_t message_size = 0;
 649        struct object *tagged;
 650        int tagged_mark;
 651        struct commit *p;
 652
 653        /* Trees have no identifier in fast-export output, thus we have no way
 654         * to output tags of trees, tags of tags of trees, etc.  Simply omit
 655         * such tags.
 656         */
 657        tagged = tag->tagged;
 658        while (tagged->type == OBJ_TAG) {
 659                tagged = ((struct tag *)tagged)->tagged;
 660        }
 661        if (tagged->type == OBJ_TREE) {
 662                warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
 663                        sha1_to_hex(tag->object.sha1));
 664                return;
 665        }
 666
 667        buf = read_sha1_file(tag->object.sha1, &type, &size);
 668        if (!buf)
 669                die ("Could not read tag %s", sha1_to_hex(tag->object.sha1));
 670        message = memmem(buf, size, "\n\n", 2);
 671        if (message) {
 672                message += 2;
 673                message_size = strlen(message);
 674        }
 675        tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
 676        if (!tagger) {
 677                if (fake_missing_tagger)
 678                        tagger = "tagger Unspecified Tagger "
 679                                "<unspecified-tagger> 0 +0000";
 680                else
 681                        tagger = "";
 682                tagger_end = tagger + strlen(tagger);
 683        } else {
 684                tagger++;
 685                tagger_end = strchrnul(tagger, '\n');
 686                if (anonymize)
 687                        anonymize_ident_line(&tagger, &tagger_end);
 688        }
 689
 690        if (anonymize) {
 691                name = anonymize_refname(name);
 692                if (message) {
 693                        static struct hashmap tags;
 694                        message = anonymize_mem(&tags, anonymize_tag,
 695                                                message, &message_size);
 696                }
 697        }
 698
 699        /* handle signed tags */
 700        if (message) {
 701                const char *signature = strstr(message,
 702                                               "\n-----BEGIN PGP SIGNATURE-----\n");
 703                if (signature)
 704                        switch(signed_tag_mode) {
 705                        case ABORT:
 706                                die ("Encountered signed tag %s; use "
 707                                     "--signed-tags=<mode> to handle it.",
 708                                     sha1_to_hex(tag->object.sha1));
 709                        case WARN:
 710                                warning ("Exporting signed tag %s",
 711                                         sha1_to_hex(tag->object.sha1));
 712                                /* fallthru */
 713                        case VERBATIM:
 714                                break;
 715                        case WARN_STRIP:
 716                                warning ("Stripping signature from tag %s",
 717                                         sha1_to_hex(tag->object.sha1));
 718                                /* fallthru */
 719                        case STRIP:
 720                                message_size = signature + 1 - message;
 721                                break;
 722                        }
 723        }
 724
 725        /* handle tag->tagged having been filtered out due to paths specified */
 726        tagged = tag->tagged;
 727        tagged_mark = get_object_mark(tagged);
 728        if (!tagged_mark) {
 729                switch(tag_of_filtered_mode) {
 730                case ABORT:
 731                        die ("Tag %s tags unexported object; use "
 732                             "--tag-of-filtered-object=<mode> to handle it.",
 733                             sha1_to_hex(tag->object.sha1));
 734                case DROP:
 735                        /* Ignore this tag altogether */
 736                        return;
 737                case REWRITE:
 738                        if (tagged->type != OBJ_COMMIT) {
 739                                die ("Tag %s tags unexported %s!",
 740                                     sha1_to_hex(tag->object.sha1),
 741                                     typename(tagged->type));
 742                        }
 743                        p = (struct commit *)tagged;
 744                        for (;;) {
 745                                if (p->parents && p->parents->next)
 746                                        break;
 747                                if (p->object.flags & UNINTERESTING)
 748                                        break;
 749                                if (!(p->object.flags & TREESAME))
 750                                        break;
 751                                if (!p->parents)
 752                                        die ("Can't find replacement commit for tag %s\n",
 753                                             sha1_to_hex(tag->object.sha1));
 754                                p = p->parents->item;
 755                        }
 756                        tagged_mark = get_object_mark(&p->object);
 757                }
 758        }
 759
 760        if (starts_with(name, "refs/tags/"))
 761                name += 10;
 762        printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
 763               name, tagged_mark,
 764               (int)(tagger_end - tagger), tagger,
 765               tagger == tagger_end ? "" : "\n",
 766               (int)message_size, (int)message_size, message ? message : "");
 767}
 768
 769static struct commit *get_commit(struct rev_cmdline_entry *e, char *full_name)
 770{
 771        switch (e->item->type) {
 772        case OBJ_COMMIT:
 773                return (struct commit *)e->item;
 774        case OBJ_TAG: {
 775                struct tag *tag = (struct tag *)e->item;
 776
 777                /* handle nested tags */
 778                while (tag && tag->object.type == OBJ_TAG) {
 779                        parse_object(tag->object.sha1);
 780                        string_list_append(&extra_refs, full_name)->util = tag;
 781                        tag = (struct tag *)tag->tagged;
 782                }
 783                if (!tag)
 784                        die("Tag %s points nowhere?", e->name);
 785                return (struct commit *)tag;
 786                break;
 787        }
 788        default:
 789                return NULL;
 790        }
 791}
 792
 793static void get_tags_and_duplicates(struct rev_cmdline_info *info)
 794{
 795        int i;
 796
 797        for (i = 0; i < info->nr; i++) {
 798                struct rev_cmdline_entry *e = info->rev + i;
 799                unsigned char sha1[20];
 800                struct commit *commit;
 801                char *full_name;
 802
 803                if (e->flags & UNINTERESTING)
 804                        continue;
 805
 806                if (dwim_ref(e->name, strlen(e->name), sha1, &full_name) != 1)
 807                        continue;
 808
 809                if (refspecs) {
 810                        char *private;
 811                        private = apply_refspecs(refspecs, refspecs_nr, full_name);
 812                        if (private) {
 813                                free(full_name);
 814                                full_name = private;
 815                        }
 816                }
 817
 818                commit = get_commit(e, full_name);
 819                if (!commit) {
 820                        warning("%s: Unexpected object of type %s, skipping.",
 821                                e->name,
 822                                typename(e->item->type));
 823                        continue;
 824                }
 825
 826                switch(commit->object.type) {
 827                case OBJ_COMMIT:
 828                        break;
 829                case OBJ_BLOB:
 830                        export_blob(commit->object.sha1);
 831                        continue;
 832                default: /* OBJ_TAG (nested tags) is already handled */
 833                        warning("Tag points to object of unexpected type %s, skipping.",
 834                                typename(commit->object.type));
 835                        continue;
 836                }
 837
 838                /*
 839                 * This ref will not be updated through a commit, lets make
 840                 * sure it gets properly updated eventually.
 841                 */
 842                if (commit->util || commit->object.flags & SHOWN)
 843                        string_list_append(&extra_refs, full_name)->util = commit;
 844                if (!commit->util)
 845                        commit->util = full_name;
 846        }
 847}
 848
 849static void handle_tags_and_duplicates(void)
 850{
 851        struct commit *commit;
 852        int i;
 853
 854        for (i = extra_refs.nr - 1; i >= 0; i--) {
 855                const char *name = extra_refs.items[i].string;
 856                struct object *object = extra_refs.items[i].util;
 857                switch (object->type) {
 858                case OBJ_TAG:
 859                        handle_tag(name, (struct tag *)object);
 860                        break;
 861                case OBJ_COMMIT:
 862                        if (anonymize)
 863                                name = anonymize_refname(name);
 864                        /* create refs pointing to already seen commits */
 865                        commit = (struct commit *)object;
 866                        printf("reset %s\nfrom :%d\n\n", name,
 867                               get_object_mark(&commit->object));
 868                        show_progress();
 869                        break;
 870                }
 871        }
 872}
 873
 874static void export_marks(char *file)
 875{
 876        unsigned int i;
 877        uint32_t mark;
 878        struct object_decoration *deco = idnums.hash;
 879        FILE *f;
 880        int e = 0;
 881
 882        f = fopen(file, "w");
 883        if (!f)
 884                die_errno("Unable to open marks file %s for writing.", file);
 885
 886        for (i = 0; i < idnums.size; i++) {
 887                if (deco->base && deco->base->type == 1) {
 888                        mark = ptr_to_mark(deco->decoration);
 889                        if (fprintf(f, ":%"PRIu32" %s\n", mark,
 890                                sha1_to_hex(deco->base->sha1)) < 0) {
 891                            e = 1;
 892                            break;
 893                        }
 894                }
 895                deco++;
 896        }
 897
 898        e |= ferror(f);
 899        e |= fclose(f);
 900        if (e)
 901                error("Unable to write marks file %s.", file);
 902}
 903
 904static void import_marks(char *input_file)
 905{
 906        char line[512];
 907        FILE *f = fopen(input_file, "r");
 908        if (!f)
 909                die_errno("cannot read '%s'", input_file);
 910
 911        while (fgets(line, sizeof(line), f)) {
 912                uint32_t mark;
 913                char *line_end, *mark_end;
 914                unsigned char sha1[20];
 915                struct object *object;
 916                struct commit *commit;
 917                enum object_type type;
 918
 919                line_end = strchr(line, '\n');
 920                if (line[0] != ':' || !line_end)
 921                        die("corrupt mark line: %s", line);
 922                *line_end = '\0';
 923
 924                mark = strtoumax(line + 1, &mark_end, 10);
 925                if (!mark || mark_end == line + 1
 926                        || *mark_end != ' ' || get_sha1_hex(mark_end + 1, sha1))
 927                        die("corrupt mark line: %s", line);
 928
 929                if (last_idnum < mark)
 930                        last_idnum = mark;
 931
 932                type = sha1_object_info(sha1, NULL);
 933                if (type < 0)
 934                        die("object not found: %s", sha1_to_hex(sha1));
 935
 936                if (type != OBJ_COMMIT)
 937                        /* only commits */
 938                        continue;
 939
 940                commit = lookup_commit(sha1);
 941                if (!commit)
 942                        die("not a commit? can't happen: %s", sha1_to_hex(sha1));
 943
 944                object = &commit->object;
 945
 946                if (object->flags & SHOWN)
 947                        error("Object %s already has a mark", sha1_to_hex(sha1));
 948
 949                mark_object(object, mark);
 950
 951                object->flags |= SHOWN;
 952        }
 953        fclose(f);
 954}
 955
 956static void handle_deletes(void)
 957{
 958        int i;
 959        for (i = 0; i < refspecs_nr; i++) {
 960                struct refspec *refspec = &refspecs[i];
 961                if (*refspec->src)
 962                        continue;
 963
 964                printf("reset %s\nfrom %s\n\n",
 965                                refspec->dst, sha1_to_hex(null_sha1));
 966        }
 967}
 968
 969int cmd_fast_export(int argc, const char **argv, const char *prefix)
 970{
 971        struct rev_info revs;
 972        struct object_array commits = OBJECT_ARRAY_INIT;
 973        struct commit *commit;
 974        char *export_filename = NULL, *import_filename = NULL;
 975        uint32_t lastimportid;
 976        struct string_list refspecs_list = STRING_LIST_INIT_NODUP;
 977        struct option options[] = {
 978                OPT_INTEGER(0, "progress", &progress,
 979                            N_("show progress after <n> objects")),
 980                OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, N_("mode"),
 981                             N_("select handling of signed tags"),
 982                             parse_opt_signed_tag_mode),
 983                OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, N_("mode"),
 984                             N_("select handling of tags that tag filtered objects"),
 985                             parse_opt_tag_of_filtered_mode),
 986                OPT_STRING(0, "export-marks", &export_filename, N_("file"),
 987                             N_("Dump marks to this file")),
 988                OPT_STRING(0, "import-marks", &import_filename, N_("file"),
 989                             N_("Import marks from this file")),
 990                OPT_BOOL(0, "fake-missing-tagger", &fake_missing_tagger,
 991                         N_("Fake a tagger when tags lack one")),
 992                OPT_BOOL(0, "full-tree", &full_tree,
 993                         N_("Output full tree for each commit")),
 994                OPT_BOOL(0, "use-done-feature", &use_done_feature,
 995                             N_("Use the done feature to terminate the stream")),
 996                OPT_BOOL(0, "no-data", &no_data, N_("Skip output of blob data")),
 997                OPT_STRING_LIST(0, "refspec", &refspecs_list, N_("refspec"),
 998                             N_("Apply refspec to exported refs")),
 999                OPT_BOOL(0, "anonymize", &anonymize, N_("anonymize output")),
1000                OPT_END()
1001        };
1002
1003        if (argc == 1)
1004                usage_with_options (fast_export_usage, options);
1005
1006        /* we handle encodings */
1007        git_config(git_default_config, NULL);
1008
1009        init_revisions(&revs, prefix);
1010        revs.topo_order = 1;
1011        revs.show_source = 1;
1012        revs.rewrite_parents = 1;
1013        argc = parse_options(argc, argv, prefix, options, fast_export_usage,
1014                        PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN);
1015        argc = setup_revisions(argc, argv, &revs, NULL);
1016        if (argc > 1)
1017                usage_with_options (fast_export_usage, options);
1018
1019        if (refspecs_list.nr) {
1020                const char **refspecs_str;
1021                int i;
1022
1023                refspecs_str = xmalloc(sizeof(*refspecs_str) * refspecs_list.nr);
1024                for (i = 0; i < refspecs_list.nr; i++)
1025                        refspecs_str[i] = refspecs_list.items[i].string;
1026
1027                refspecs_nr = refspecs_list.nr;
1028                refspecs = parse_fetch_refspec(refspecs_nr, refspecs_str);
1029
1030                string_list_clear(&refspecs_list, 1);
1031                free(refspecs_str);
1032        }
1033
1034        if (use_done_feature)
1035                printf("feature done\n");
1036
1037        if (import_filename)
1038                import_marks(import_filename);
1039        lastimportid = last_idnum;
1040
1041        if (import_filename && revs.prune_data.nr)
1042                full_tree = 1;
1043
1044        get_tags_and_duplicates(&revs.cmdline);
1045
1046        if (prepare_revision_walk(&revs))
1047                die("revision walk setup failed");
1048        revs.diffopt.format_callback = show_filemodify;
1049        DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1050        while ((commit = get_revision(&revs))) {
1051                if (has_unshown_parent(commit)) {
1052                        add_object_array(&commit->object, NULL, &commits);
1053                }
1054                else {
1055                        handle_commit(commit, &revs);
1056                        handle_tail(&commits, &revs);
1057                }
1058        }
1059
1060        handle_tags_and_duplicates();
1061        handle_deletes();
1062
1063        if (export_filename && lastimportid != last_idnum)
1064                export_marks(export_filename);
1065
1066        if (use_done_feature)
1067                printf("done\n");
1068
1069        free_refspec(refspecs_nr, refspecs);
1070
1071        return 0;
1072}