builtin / fast-export.con commit Merge branch 'jc/utf8-fprintf' (62458ea)
   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 "commit.h"
  11#include "object.h"
  12#include "tag.h"
  13#include "diff.h"
  14#include "diffcore.h"
  15#include "log-tree.h"
  16#include "revision.h"
  17#include "decorate.h"
  18#include "string-list.h"
  19#include "utf8.h"
  20#include "parse-options.h"
  21#include "quote.h"
  22#include "remote.h"
  23#include "blob.h"
  24
  25static const char *fast_export_usage[] = {
  26        N_("git fast-export [rev-list-opts]"),
  27        NULL
  28};
  29
  30static int progress;
  31static enum { ABORT, VERBATIM, WARN, WARN_STRIP, STRIP } signed_tag_mode = ABORT;
  32static enum { ERROR, DROP, REWRITE } tag_of_filtered_mode = ERROR;
  33static int fake_missing_tagger;
  34static int use_done_feature;
  35static int no_data;
  36static int full_tree;
  37static struct string_list extra_refs = STRING_LIST_INIT_NODUP;
  38static struct refspec *refspecs;
  39static int refspecs_nr;
  40static int anonymize;
  41
  42static int parse_opt_signed_tag_mode(const struct option *opt,
  43                                     const char *arg, int unset)
  44{
  45        if (unset || !strcmp(arg, "abort"))
  46                signed_tag_mode = ABORT;
  47        else if (!strcmp(arg, "verbatim") || !strcmp(arg, "ignore"))
  48                signed_tag_mode = VERBATIM;
  49        else if (!strcmp(arg, "warn"))
  50                signed_tag_mode = WARN;
  51        else if (!strcmp(arg, "warn-strip"))
  52                signed_tag_mode = WARN_STRIP;
  53        else if (!strcmp(arg, "strip"))
  54                signed_tag_mode = STRIP;
  55        else
  56                return error("Unknown signed-tags mode: %s", arg);
  57        return 0;
  58}
  59
  60static int parse_opt_tag_of_filtered_mode(const struct option *opt,
  61                                          const char *arg, int unset)
  62{
  63        if (unset || !strcmp(arg, "abort"))
  64                tag_of_filtered_mode = ERROR;
  65        else if (!strcmp(arg, "drop"))
  66                tag_of_filtered_mode = DROP;
  67        else if (!strcmp(arg, "rewrite"))
  68                tag_of_filtered_mode = REWRITE;
  69        else
  70                return error("Unknown tag-of-filtered mode: %s", arg);
  71        return 0;
  72}
  73
  74static struct decoration idnums;
  75static uint32_t last_idnum;
  76
  77static int has_unshown_parent(struct commit *commit)
  78{
  79        struct commit_list *parent;
  80
  81        for (parent = commit->parents; parent; parent = parent->next)
  82                if (!(parent->item->object.flags & SHOWN) &&
  83                    !(parent->item->object.flags & UNINTERESTING))
  84                        return 1;
  85        return 0;
  86}
  87
  88struct anonymized_entry {
  89        struct hashmap_entry hash;
  90        const char *orig;
  91        size_t orig_len;
  92        const char *anon;
  93        size_t anon_len;
  94};
  95
  96static int anonymized_entry_cmp(const void *va, const void *vb,
  97                                const void *data)
  98{
  99        const struct anonymized_entry *a = va, *b = vb;
 100        return a->orig_len != b->orig_len ||
 101                memcmp(a->orig, b->orig, a->orig_len);
 102}
 103
 104/*
 105 * Basically keep a cache of X->Y so that we can repeatedly replace
 106 * the same anonymized string with another. The actual generation
 107 * is farmed out to the generate function.
 108 */
 109static const void *anonymize_mem(struct hashmap *map,
 110                                 void *(*generate)(const void *, size_t *),
 111                                 const void *orig, size_t *len)
 112{
 113        struct anonymized_entry key, *ret;
 114
 115        if (!map->cmpfn)
 116                hashmap_init(map, anonymized_entry_cmp, 0);
 117
 118        hashmap_entry_init(&key, memhash(orig, *len));
 119        key.orig = orig;
 120        key.orig_len = *len;
 121        ret = hashmap_get(map, &key, NULL);
 122
 123        if (!ret) {
 124                ret = xmalloc(sizeof(*ret));
 125                hashmap_entry_init(&ret->hash, key.hash.hash);
 126                ret->orig = xstrdup(orig);
 127                ret->orig_len = *len;
 128                ret->anon = generate(orig, len);
 129                ret->anon_len = *len;
 130                hashmap_put(map, ret);
 131        }
 132
 133        *len = ret->anon_len;
 134        return ret->anon;
 135}
 136
 137/*
 138 * We anonymize each component of a path individually,
 139 * so that paths a/b and a/c will share a common root.
 140 * The paths are cached via anonymize_mem so that repeated
 141 * lookups for "a" will yield the same value.
 142 */
 143static void anonymize_path(struct strbuf *out, const char *path,
 144                           struct hashmap *map,
 145                           void *(*generate)(const void *, size_t *))
 146{
 147        while (*path) {
 148                const char *end_of_component = strchrnul(path, '/');
 149                size_t len = end_of_component - path;
 150                const char *c = anonymize_mem(map, generate, path, &len);
 151                strbuf_add(out, c, len);
 152                path = end_of_component;
 153                if (*path)
 154                        strbuf_addch(out, *path++);
 155        }
 156}
 157
 158/* Since intptr_t is C99, we do not use it here */
 159static inline uint32_t *mark_to_ptr(uint32_t mark)
 160{
 161        return ((uint32_t *)NULL) + mark;
 162}
 163
 164static inline uint32_t ptr_to_mark(void * mark)
 165{
 166        return (uint32_t *)mark - (uint32_t *)NULL;
 167}
 168
 169static inline void mark_object(struct object *object, uint32_t mark)
 170{
 171        add_decoration(&idnums, object, mark_to_ptr(mark));
 172}
 173
 174static inline void mark_next_object(struct object *object)
 175{
 176        mark_object(object, ++last_idnum);
 177}
 178
 179static int get_object_mark(struct object *object)
 180{
 181        void *decoration = lookup_decoration(&idnums, object);
 182        if (!decoration)
 183                return 0;
 184        return ptr_to_mark(decoration);
 185}
 186
 187static void show_progress(void)
 188{
 189        static int counter = 0;
 190        if (!progress)
 191                return;
 192        if ((++counter % progress) == 0)
 193                printf("progress %d objects\n", counter);
 194}
 195
 196/*
 197 * Ideally we would want some transformation of the blob data here
 198 * that is unreversible, but would still be the same size and have
 199 * the same data relationship to other blobs (so that we get the same
 200 * delta and packing behavior as the original). But the first and last
 201 * requirements there are probably mutually exclusive, so let's take
 202 * the easy way out for now, and just generate arbitrary content.
 203 *
 204 * There's no need to cache this result with anonymize_mem, since
 205 * we already handle blob content caching with marks.
 206 */
 207static char *anonymize_blob(unsigned long *size)
 208{
 209        static int counter;
 210        struct strbuf out = STRBUF_INIT;
 211        strbuf_addf(&out, "anonymous blob %d", counter++);
 212        *size = out.len;
 213        return strbuf_detach(&out, NULL);
 214}
 215
 216static void export_blob(const struct object_id *oid)
 217{
 218        unsigned long size;
 219        enum object_type type;
 220        char *buf;
 221        struct object *object;
 222        int eaten;
 223
 224        if (no_data)
 225                return;
 226
 227        if (is_null_oid(oid))
 228                return;
 229
 230        object = lookup_object(oid->hash);
 231        if (object && object->flags & SHOWN)
 232                return;
 233
 234        if (anonymize) {
 235                buf = anonymize_blob(&size);
 236                object = (struct object *)lookup_blob(oid);
 237                eaten = 0;
 238        } else {
 239                buf = read_sha1_file(oid->hash, &type, &size);
 240                if (!buf)
 241                        die ("Could not read blob %s", oid_to_hex(oid));
 242                if (check_sha1_signature(oid->hash, buf, size, typename(type)) < 0)
 243                        die("sha1 mismatch in blob %s", oid_to_hex(oid));
 244                object = parse_object_buffer(oid, type, size, buf, &eaten);
 245        }
 246
 247        if (!object)
 248                die("Could not read blob %s", oid_to_hex(oid));
 249
 250        mark_next_object(object);
 251
 252        printf("blob\nmark :%"PRIu32"\ndata %lu\n", last_idnum, size);
 253        if (size && fwrite(buf, size, 1, stdout) != 1)
 254                die_errno ("Could not write blob '%s'", oid_to_hex(oid));
 255        printf("\n");
 256
 257        show_progress();
 258
 259        object->flags |= SHOWN;
 260        if (!eaten)
 261                free(buf);
 262}
 263
 264static int depth_first(const void *a_, const void *b_)
 265{
 266        const struct diff_filepair *a = *((const struct diff_filepair **)a_);
 267        const struct diff_filepair *b = *((const struct diff_filepair **)b_);
 268        const char *name_a, *name_b;
 269        int len_a, len_b, len;
 270        int cmp;
 271
 272        name_a = a->one ? a->one->path : a->two->path;
 273        name_b = b->one ? b->one->path : b->two->path;
 274
 275        len_a = strlen(name_a);
 276        len_b = strlen(name_b);
 277        len = (len_a < len_b) ? len_a : len_b;
 278
 279        /* strcmp will sort 'd' before 'd/e', we want 'd/e' before 'd' */
 280        cmp = memcmp(name_a, name_b, len);
 281        if (cmp)
 282                return cmp;
 283        cmp = len_b - len_a;
 284        if (cmp)
 285                return cmp;
 286        /*
 287         * Move 'R'ename entries last so that all references of the file
 288         * appear in the output before it is renamed (e.g., when a file
 289         * was copied and renamed in the same commit).
 290         */
 291        return (a->status == 'R') - (b->status == 'R');
 292}
 293
 294static void print_path_1(const char *path)
 295{
 296        int need_quote = quote_c_style(path, NULL, NULL, 0);
 297        if (need_quote)
 298                quote_c_style(path, NULL, stdout, 0);
 299        else if (strchr(path, ' '))
 300                printf("\"%s\"", path);
 301        else
 302                printf("%s", path);
 303}
 304
 305static void *anonymize_path_component(const void *path, size_t *len)
 306{
 307        static int counter;
 308        struct strbuf out = STRBUF_INIT;
 309        strbuf_addf(&out, "path%d", counter++);
 310        return strbuf_detach(&out, len);
 311}
 312
 313static void print_path(const char *path)
 314{
 315        if (!anonymize)
 316                print_path_1(path);
 317        else {
 318                static struct hashmap paths;
 319                static struct strbuf anon = STRBUF_INIT;
 320
 321                anonymize_path(&anon, path, &paths, anonymize_path_component);
 322                print_path_1(anon.buf);
 323                strbuf_reset(&anon);
 324        }
 325}
 326
 327static void *generate_fake_oid(const void *old, size_t *len)
 328{
 329        static uint32_t counter = 1; /* avoid null sha1 */
 330        unsigned char *out = xcalloc(GIT_SHA1_RAWSZ, 1);
 331        put_be32(out + GIT_SHA1_RAWSZ - 4, counter++);
 332        return out;
 333}
 334
 335static const unsigned char *anonymize_sha1(const struct object_id *oid)
 336{
 337        static struct hashmap sha1s;
 338        size_t len = GIT_SHA1_RAWSZ;
 339        return anonymize_mem(&sha1s, generate_fake_oid, oid, &len);
 340}
 341
 342static void show_filemodify(struct diff_queue_struct *q,
 343                            struct diff_options *options, void *data)
 344{
 345        int i;
 346
 347        /*
 348         * Handle files below a directory first, in case they are all deleted
 349         * and the directory changes to a file or symlink.
 350         */
 351        QSORT(q->queue, q->nr, depth_first);
 352
 353        for (i = 0; i < q->nr; i++) {
 354                struct diff_filespec *ospec = q->queue[i]->one;
 355                struct diff_filespec *spec = q->queue[i]->two;
 356
 357                switch (q->queue[i]->status) {
 358                case DIFF_STATUS_DELETED:
 359                        printf("D ");
 360                        print_path(spec->path);
 361                        putchar('\n');
 362                        break;
 363
 364                case DIFF_STATUS_COPIED:
 365                case DIFF_STATUS_RENAMED:
 366                        printf("%c ", q->queue[i]->status);
 367                        print_path(ospec->path);
 368                        putchar(' ');
 369                        print_path(spec->path);
 370                        putchar('\n');
 371
 372                        if (!oidcmp(&ospec->oid, &spec->oid) &&
 373                            ospec->mode == spec->mode)
 374                                break;
 375                        /* fallthrough */
 376
 377                case DIFF_STATUS_TYPE_CHANGED:
 378                case DIFF_STATUS_MODIFIED:
 379                case DIFF_STATUS_ADDED:
 380                        /*
 381                         * Links refer to objects in another repositories;
 382                         * output the SHA-1 verbatim.
 383                         */
 384                        if (no_data || S_ISGITLINK(spec->mode))
 385                                printf("M %06o %s ", spec->mode,
 386                                       sha1_to_hex(anonymize ?
 387                                                   anonymize_sha1(&spec->oid) :
 388                                                   spec->oid.hash));
 389                        else {
 390                                struct object *object = lookup_object(spec->oid.hash);
 391                                printf("M %06o :%d ", spec->mode,
 392                                       get_object_mark(object));
 393                        }
 394                        print_path(spec->path);
 395                        putchar('\n');
 396                        break;
 397
 398                default:
 399                        die("Unexpected comparison status '%c' for %s, %s",
 400                                q->queue[i]->status,
 401                                ospec->path ? ospec->path : "none",
 402                                spec->path ? spec->path : "none");
 403                }
 404        }
 405}
 406
 407static const char *find_encoding(const char *begin, const char *end)
 408{
 409        const char *needle = "\nencoding ";
 410        char *bol, *eol;
 411
 412        bol = memmem(begin, end ? end - begin : strlen(begin),
 413                     needle, strlen(needle));
 414        if (!bol)
 415                return git_commit_encoding;
 416        bol += strlen(needle);
 417        eol = strchrnul(bol, '\n');
 418        *eol = '\0';
 419        return bol;
 420}
 421
 422static void *anonymize_ref_component(const void *old, size_t *len)
 423{
 424        static int counter;
 425        struct strbuf out = STRBUF_INIT;
 426        strbuf_addf(&out, "ref%d", counter++);
 427        return strbuf_detach(&out, len);
 428}
 429
 430static const char *anonymize_refname(const char *refname)
 431{
 432        /*
 433         * If any of these prefixes is found, we will leave it intact
 434         * so that tags remain tags and so forth.
 435         */
 436        static const char *prefixes[] = {
 437                "refs/heads/",
 438                "refs/tags/",
 439                "refs/remotes/",
 440                "refs/"
 441        };
 442        static struct hashmap refs;
 443        static struct strbuf anon = STRBUF_INIT;
 444        int i;
 445
 446        /*
 447         * We also leave "master" as a special case, since it does not reveal
 448         * anything interesting.
 449         */
 450        if (!strcmp(refname, "refs/heads/master"))
 451                return refname;
 452
 453        strbuf_reset(&anon);
 454        for (i = 0; i < ARRAY_SIZE(prefixes); i++) {
 455                if (skip_prefix(refname, prefixes[i], &refname)) {
 456                        strbuf_addstr(&anon, prefixes[i]);
 457                        break;
 458                }
 459        }
 460
 461        anonymize_path(&anon, refname, &refs, anonymize_ref_component);
 462        return anon.buf;
 463}
 464
 465/*
 466 * We do not even bother to cache commit messages, as they are unlikely
 467 * to be repeated verbatim, and it is not that interesting when they are.
 468 */
 469static char *anonymize_commit_message(const char *old)
 470{
 471        static int counter;
 472        return xstrfmt("subject %d\n\nbody\n", counter++);
 473}
 474
 475static struct hashmap idents;
 476static void *anonymize_ident(const void *old, size_t *len)
 477{
 478        static int counter;
 479        struct strbuf out = STRBUF_INIT;
 480        strbuf_addf(&out, "User %d <user%d@example.com>", counter, counter);
 481        counter++;
 482        return strbuf_detach(&out, len);
 483}
 484
 485/*
 486 * Our strategy here is to anonymize the names and email addresses,
 487 * but keep timestamps intact, as they influence things like traversal
 488 * order (and by themselves should not be too revealing).
 489 */
 490static void anonymize_ident_line(const char **beg, const char **end)
 491{
 492        static struct strbuf buffers[] = { STRBUF_INIT, STRBUF_INIT };
 493        static unsigned which_buffer;
 494
 495        struct strbuf *out;
 496        struct ident_split split;
 497        const char *end_of_header;
 498
 499        out = &buffers[which_buffer++];
 500        which_buffer %= ARRAY_SIZE(buffers);
 501        strbuf_reset(out);
 502
 503        /* skip "committer", "author", "tagger", etc */
 504        end_of_header = strchr(*beg, ' ');
 505        if (!end_of_header)
 506                die("BUG: malformed line fed to anonymize_ident_line: %.*s",
 507                    (int)(*end - *beg), *beg);
 508        end_of_header++;
 509        strbuf_add(out, *beg, end_of_header - *beg);
 510
 511        if (!split_ident_line(&split, end_of_header, *end - end_of_header) &&
 512            split.date_begin) {
 513                const char *ident;
 514                size_t len;
 515
 516                len = split.mail_end - split.name_begin;
 517                ident = anonymize_mem(&idents, anonymize_ident,
 518                                      split.name_begin, &len);
 519                strbuf_add(out, ident, len);
 520                strbuf_addch(out, ' ');
 521                strbuf_add(out, split.date_begin, split.tz_end - split.date_begin);
 522        } else {
 523                strbuf_addstr(out, "Malformed Ident <malformed@example.com> 0 -0000");
 524        }
 525
 526        *beg = out->buf;
 527        *end = out->buf + out->len;
 528}
 529
 530static void handle_commit(struct commit *commit, struct rev_info *rev)
 531{
 532        int saved_output_format = rev->diffopt.output_format;
 533        const char *commit_buffer;
 534        const char *author, *author_end, *committer, *committer_end;
 535        const char *encoding, *message;
 536        char *reencoded = NULL;
 537        struct commit_list *p;
 538        const char *refname;
 539        int i;
 540
 541        rev->diffopt.output_format = DIFF_FORMAT_CALLBACK;
 542
 543        parse_commit_or_die(commit);
 544        commit_buffer = get_commit_buffer(commit, NULL);
 545        author = strstr(commit_buffer, "\nauthor ");
 546        if (!author)
 547                die ("Could not find author in commit %s",
 548                     oid_to_hex(&commit->object.oid));
 549        author++;
 550        author_end = strchrnul(author, '\n');
 551        committer = strstr(author_end, "\ncommitter ");
 552        if (!committer)
 553                die ("Could not find committer in commit %s",
 554                     oid_to_hex(&commit->object.oid));
 555        committer++;
 556        committer_end = strchrnul(committer, '\n');
 557        message = strstr(committer_end, "\n\n");
 558        encoding = find_encoding(committer_end, message);
 559        if (message)
 560                message += 2;
 561
 562        if (commit->parents &&
 563            get_object_mark(&commit->parents->item->object) != 0 &&
 564            !full_tree) {
 565                parse_commit_or_die(commit->parents->item);
 566                diff_tree_oid(&commit->parents->item->tree->object.oid,
 567                              &commit->tree->object.oid, "", &rev->diffopt);
 568        }
 569        else
 570                diff_root_tree_oid(&commit->tree->object.oid,
 571                                   "", &rev->diffopt);
 572
 573        /* Export the referenced blobs, and remember the marks. */
 574        for (i = 0; i < diff_queued_diff.nr; i++)
 575                if (!S_ISGITLINK(diff_queued_diff.queue[i]->two->mode))
 576                        export_blob(&diff_queued_diff.queue[i]->two->oid);
 577
 578        refname = commit->util;
 579        if (anonymize) {
 580                refname = anonymize_refname(refname);
 581                anonymize_ident_line(&committer, &committer_end);
 582                anonymize_ident_line(&author, &author_end);
 583        }
 584
 585        mark_next_object(&commit->object);
 586        if (anonymize)
 587                reencoded = anonymize_commit_message(message);
 588        else if (!is_encoding_utf8(encoding))
 589                reencoded = reencode_string(message, "UTF-8", encoding);
 590        if (!commit->parents)
 591                printf("reset %s\n", refname);
 592        printf("commit %s\nmark :%"PRIu32"\n%.*s\n%.*s\ndata %u\n%s",
 593               refname, last_idnum,
 594               (int)(author_end - author), author,
 595               (int)(committer_end - committer), committer,
 596               (unsigned)(reencoded
 597                          ? strlen(reencoded) : message
 598                          ? strlen(message) : 0),
 599               reencoded ? reencoded : message ? message : "");
 600        free(reencoded);
 601        unuse_commit_buffer(commit, commit_buffer);
 602
 603        for (i = 0, p = commit->parents; p; p = p->next) {
 604                int mark = get_object_mark(&p->item->object);
 605                if (!mark)
 606                        continue;
 607                if (i == 0)
 608                        printf("from :%d\n", mark);
 609                else
 610                        printf("merge :%d\n", mark);
 611                i++;
 612        }
 613
 614        if (full_tree)
 615                printf("deleteall\n");
 616        log_tree_diff_flush(rev);
 617        rev->diffopt.output_format = saved_output_format;
 618
 619        printf("\n");
 620
 621        show_progress();
 622}
 623
 624static void *anonymize_tag(const void *old, size_t *len)
 625{
 626        static int counter;
 627        struct strbuf out = STRBUF_INIT;
 628        strbuf_addf(&out, "tag message %d", counter++);
 629        return strbuf_detach(&out, len);
 630}
 631
 632static void handle_tail(struct object_array *commits, struct rev_info *revs)
 633{
 634        struct commit *commit;
 635        while (commits->nr) {
 636                commit = (struct commit *)commits->objects[commits->nr - 1].item;
 637                if (has_unshown_parent(commit))
 638                        return;
 639                handle_commit(commit, revs);
 640                commits->nr--;
 641        }
 642}
 643
 644static void handle_tag(const char *name, struct tag *tag)
 645{
 646        unsigned long size;
 647        enum object_type type;
 648        char *buf;
 649        const char *tagger, *tagger_end, *message;
 650        size_t message_size = 0;
 651        struct object *tagged;
 652        int tagged_mark;
 653        struct commit *p;
 654
 655        /* Trees have no identifier in fast-export output, thus we have no way
 656         * to output tags of trees, tags of tags of trees, etc.  Simply omit
 657         * such tags.
 658         */
 659        tagged = tag->tagged;
 660        while (tagged->type == OBJ_TAG) {
 661                tagged = ((struct tag *)tagged)->tagged;
 662        }
 663        if (tagged->type == OBJ_TREE) {
 664                warning("Omitting tag %s,\nsince tags of trees (or tags of tags of trees, etc.) are not supported.",
 665                        oid_to_hex(&tag->object.oid));
 666                return;
 667        }
 668
 669        buf = read_sha1_file(tag->object.oid.hash, &type, &size);
 670        if (!buf)
 671                die ("Could not read tag %s", oid_to_hex(&tag->object.oid));
 672        message = memmem(buf, size, "\n\n", 2);
 673        if (message) {
 674                message += 2;
 675                message_size = strlen(message);
 676        }
 677        tagger = memmem(buf, message ? message - buf : size, "\ntagger ", 8);
 678        if (!tagger) {
 679                if (fake_missing_tagger)
 680                        tagger = "tagger Unspecified Tagger "
 681                                "<unspecified-tagger> 0 +0000";
 682                else
 683                        tagger = "";
 684                tagger_end = tagger + strlen(tagger);
 685        } else {
 686                tagger++;
 687                tagger_end = strchrnul(tagger, '\n');
 688                if (anonymize)
 689                        anonymize_ident_line(&tagger, &tagger_end);
 690        }
 691
 692        if (anonymize) {
 693                name = anonymize_refname(name);
 694                if (message) {
 695                        static struct hashmap tags;
 696                        message = anonymize_mem(&tags, anonymize_tag,
 697                                                message, &message_size);
 698                }
 699        }
 700
 701        /* handle signed tags */
 702        if (message) {
 703                const char *signature = strstr(message,
 704                                               "\n-----BEGIN PGP SIGNATURE-----\n");
 705                if (signature)
 706                        switch(signed_tag_mode) {
 707                        case ABORT:
 708                                die ("Encountered signed tag %s; use "
 709                                     "--signed-tags=<mode> to handle it.",
 710                                     oid_to_hex(&tag->object.oid));
 711                        case WARN:
 712                                warning ("Exporting signed tag %s",
 713                                         oid_to_hex(&tag->object.oid));
 714                                /* fallthru */
 715                        case VERBATIM:
 716                                break;
 717                        case WARN_STRIP:
 718                                warning ("Stripping signature from tag %s",
 719                                         oid_to_hex(&tag->object.oid));
 720                                /* fallthru */
 721                        case STRIP:
 722                                message_size = signature + 1 - message;
 723                                break;
 724                        }
 725        }
 726
 727        /* handle tag->tagged having been filtered out due to paths specified */
 728        tagged = tag->tagged;
 729        tagged_mark = get_object_mark(tagged);
 730        if (!tagged_mark) {
 731                switch(tag_of_filtered_mode) {
 732                case ABORT:
 733                        die ("Tag %s tags unexported object; use "
 734                             "--tag-of-filtered-object=<mode> to handle it.",
 735                             oid_to_hex(&tag->object.oid));
 736                case DROP:
 737                        /* Ignore this tag altogether */
 738                        free(buf);
 739                        return;
 740                case REWRITE:
 741                        if (tagged->type != OBJ_COMMIT) {
 742                                die ("Tag %s tags unexported %s!",
 743                                     oid_to_hex(&tag->object.oid),
 744                                     typename(tagged->type));
 745                        }
 746                        p = (struct commit *)tagged;
 747                        for (;;) {
 748                                if (p->parents && p->parents->next)
 749                                        break;
 750                                if (p->object.flags & UNINTERESTING)
 751                                        break;
 752                                if (!(p->object.flags & TREESAME))
 753                                        break;
 754                                if (!p->parents)
 755                                        die ("Can't find replacement commit for tag %s\n",
 756                                             oid_to_hex(&tag->object.oid));
 757                                p = p->parents->item;
 758                        }
 759                        tagged_mark = get_object_mark(&p->object);
 760                }
 761        }
 762
 763        if (starts_with(name, "refs/tags/"))
 764                name += 10;
 765        printf("tag %s\nfrom :%d\n%.*s%sdata %d\n%.*s\n",
 766               name, tagged_mark,
 767               (int)(tagger_end - tagger), tagger,
 768               tagger == tagger_end ? "" : "\n",
 769               (int)message_size, (int)message_size, message ? message : "");
 770        free(buf);
 771}
 772
 773static struct commit *get_commit(struct rev_cmdline_entry *e, char *full_name)
 774{
 775        switch (e->item->type) {
 776        case OBJ_COMMIT:
 777                return (struct commit *)e->item;
 778        case OBJ_TAG: {
 779                struct tag *tag = (struct tag *)e->item;
 780
 781                /* handle nested tags */
 782                while (tag && tag->object.type == OBJ_TAG) {
 783                        parse_object(&tag->object.oid);
 784                        string_list_append(&extra_refs, full_name)->util = tag;
 785                        tag = (struct tag *)tag->tagged;
 786                }
 787                if (!tag)
 788                        die("Tag %s points nowhere?", e->name);
 789                return (struct commit *)tag;
 790                break;
 791        }
 792        default:
 793                return NULL;
 794        }
 795}
 796
 797static void get_tags_and_duplicates(struct rev_cmdline_info *info)
 798{
 799        int i;
 800
 801        for (i = 0; i < info->nr; i++) {
 802                struct rev_cmdline_entry *e = info->rev + i;
 803                struct object_id oid;
 804                struct commit *commit;
 805                char *full_name;
 806
 807                if (e->flags & UNINTERESTING)
 808                        continue;
 809
 810                if (dwim_ref(e->name, strlen(e->name), oid.hash, &full_name) != 1)
 811                        continue;
 812
 813                if (refspecs) {
 814                        char *private;
 815                        private = apply_refspecs(refspecs, refspecs_nr, full_name);
 816                        if (private) {
 817                                free(full_name);
 818                                full_name = private;
 819                        }
 820                }
 821
 822                commit = get_commit(e, full_name);
 823                if (!commit) {
 824                        warning("%s: Unexpected object of type %s, skipping.",
 825                                e->name,
 826                                typename(e->item->type));
 827                        continue;
 828                }
 829
 830                switch(commit->object.type) {
 831                case OBJ_COMMIT:
 832                        break;
 833                case OBJ_BLOB:
 834                        export_blob(&commit->object.oid);
 835                        continue;
 836                default: /* OBJ_TAG (nested tags) is already handled */
 837                        warning("Tag points to object of unexpected type %s, skipping.",
 838                                typename(commit->object.type));
 839                        continue;
 840                }
 841
 842                /*
 843                 * This ref will not be updated through a commit, lets make
 844                 * sure it gets properly updated eventually.
 845                 */
 846                if (commit->util || commit->object.flags & SHOWN)
 847                        string_list_append(&extra_refs, full_name)->util = commit;
 848                if (!commit->util)
 849                        commit->util = full_name;
 850        }
 851}
 852
 853static void handle_tags_and_duplicates(void)
 854{
 855        struct commit *commit;
 856        int i;
 857
 858        for (i = extra_refs.nr - 1; i >= 0; i--) {
 859                const char *name = extra_refs.items[i].string;
 860                struct object *object = extra_refs.items[i].util;
 861                switch (object->type) {
 862                case OBJ_TAG:
 863                        handle_tag(name, (struct tag *)object);
 864                        break;
 865                case OBJ_COMMIT:
 866                        if (anonymize)
 867                                name = anonymize_refname(name);
 868                        /* create refs pointing to already seen commits */
 869                        commit = (struct commit *)object;
 870                        printf("reset %s\nfrom :%d\n\n", name,
 871                               get_object_mark(&commit->object));
 872                        show_progress();
 873                        break;
 874                }
 875        }
 876}
 877
 878static void export_marks(char *file)
 879{
 880        unsigned int i;
 881        uint32_t mark;
 882        struct object_decoration *deco = idnums.hash;
 883        FILE *f;
 884        int e = 0;
 885
 886        f = fopen_for_writing(file);
 887        if (!f)
 888                die_errno("Unable to open marks file %s for writing.", file);
 889
 890        for (i = 0; i < idnums.size; i++) {
 891                if (deco->base && deco->base->type == 1) {
 892                        mark = ptr_to_mark(deco->decoration);
 893                        if (fprintf(f, ":%"PRIu32" %s\n", mark,
 894                                oid_to_hex(&deco->base->oid)) < 0) {
 895                            e = 1;
 896                            break;
 897                        }
 898                }
 899                deco++;
 900        }
 901
 902        e |= ferror(f);
 903        e |= fclose(f);
 904        if (e)
 905                error("Unable to write marks file %s.", file);
 906}
 907
 908static void import_marks(char *input_file)
 909{
 910        char line[512];
 911        FILE *f = xfopen(input_file, "r");
 912
 913        while (fgets(line, sizeof(line), f)) {
 914                uint32_t mark;
 915                char *line_end, *mark_end;
 916                struct object_id oid;
 917                struct object *object;
 918                struct commit *commit;
 919                enum object_type type;
 920
 921                line_end = strchr(line, '\n');
 922                if (line[0] != ':' || !line_end)
 923                        die("corrupt mark line: %s", line);
 924                *line_end = '\0';
 925
 926                mark = strtoumax(line + 1, &mark_end, 10);
 927                if (!mark || mark_end == line + 1
 928                        || *mark_end != ' ' || get_oid_hex(mark_end + 1, &oid))
 929                        die("corrupt mark line: %s", line);
 930
 931                if (last_idnum < mark)
 932                        last_idnum = mark;
 933
 934                type = sha1_object_info(oid.hash, NULL);
 935                if (type < 0)
 936                        die("object not found: %s", oid_to_hex(&oid));
 937
 938                if (type != OBJ_COMMIT)
 939                        /* only commits */
 940                        continue;
 941
 942                commit = lookup_commit(&oid);
 943                if (!commit)
 944                        die("not a commit? can't happen: %s", oid_to_hex(&oid));
 945
 946                object = &commit->object;
 947
 948                if (object->flags & SHOWN)
 949                        error("Object %s already has a mark", oid_to_hex(&oid));
 950
 951                mark_object(object, mark);
 952
 953                object->flags |= SHOWN;
 954        }
 955        fclose(f);
 956}
 957
 958static void handle_deletes(void)
 959{
 960        int i;
 961        for (i = 0; i < refspecs_nr; i++) {
 962                struct refspec *refspec = &refspecs[i];
 963                if (*refspec->src)
 964                        continue;
 965
 966                printf("reset %s\nfrom %s\n\n",
 967                                refspec->dst, sha1_to_hex(null_sha1));
 968        }
 969}
 970
 971int cmd_fast_export(int argc, const char **argv, const char *prefix)
 972{
 973        struct rev_info revs;
 974        struct object_array commits = OBJECT_ARRAY_INIT;
 975        struct commit *commit;
 976        char *export_filename = NULL, *import_filename = NULL;
 977        uint32_t lastimportid;
 978        struct string_list refspecs_list = STRING_LIST_INIT_NODUP;
 979        struct option options[] = {
 980                OPT_INTEGER(0, "progress", &progress,
 981                            N_("show progress after <n> objects")),
 982                OPT_CALLBACK(0, "signed-tags", &signed_tag_mode, N_("mode"),
 983                             N_("select handling of signed tags"),
 984                             parse_opt_signed_tag_mode),
 985                OPT_CALLBACK(0, "tag-of-filtered-object", &tag_of_filtered_mode, N_("mode"),
 986                             N_("select handling of tags that tag filtered objects"),
 987                             parse_opt_tag_of_filtered_mode),
 988                OPT_STRING(0, "export-marks", &export_filename, N_("file"),
 989                             N_("Dump marks to this file")),
 990                OPT_STRING(0, "import-marks", &import_filename, N_("file"),
 991                             N_("Import marks from this file")),
 992                OPT_BOOL(0, "fake-missing-tagger", &fake_missing_tagger,
 993                         N_("Fake a tagger when tags lack one")),
 994                OPT_BOOL(0, "full-tree", &full_tree,
 995                         N_("Output full tree for each commit")),
 996                OPT_BOOL(0, "use-done-feature", &use_done_feature,
 997                             N_("Use the done feature to terminate the stream")),
 998                OPT_BOOL(0, "no-data", &no_data, N_("Skip output of blob data")),
 999                OPT_STRING_LIST(0, "refspec", &refspecs_list, N_("refspec"),
1000                             N_("Apply refspec to exported refs")),
1001                OPT_BOOL(0, "anonymize", &anonymize, N_("anonymize output")),
1002                OPT_END()
1003        };
1004
1005        if (argc == 1)
1006                usage_with_options (fast_export_usage, options);
1007
1008        /* we handle encodings */
1009        git_config(git_default_config, NULL);
1010
1011        init_revisions(&revs, prefix);
1012        revs.topo_order = 1;
1013        revs.show_source = 1;
1014        revs.rewrite_parents = 1;
1015        argc = parse_options(argc, argv, prefix, options, fast_export_usage,
1016                        PARSE_OPT_KEEP_ARGV0 | PARSE_OPT_KEEP_UNKNOWN);
1017        argc = setup_revisions(argc, argv, &revs, NULL);
1018        if (argc > 1)
1019                usage_with_options (fast_export_usage, options);
1020
1021        if (refspecs_list.nr) {
1022                const char **refspecs_str;
1023                int i;
1024
1025                ALLOC_ARRAY(refspecs_str, refspecs_list.nr);
1026                for (i = 0; i < refspecs_list.nr; i++)
1027                        refspecs_str[i] = refspecs_list.items[i].string;
1028
1029                refspecs_nr = refspecs_list.nr;
1030                refspecs = parse_fetch_refspec(refspecs_nr, refspecs_str);
1031
1032                string_list_clear(&refspecs_list, 1);
1033                free(refspecs_str);
1034        }
1035
1036        if (use_done_feature)
1037                printf("feature done\n");
1038
1039        if (import_filename)
1040                import_marks(import_filename);
1041        lastimportid = last_idnum;
1042
1043        if (import_filename && revs.prune_data.nr)
1044                full_tree = 1;
1045
1046        get_tags_and_duplicates(&revs.cmdline);
1047
1048        if (prepare_revision_walk(&revs))
1049                die("revision walk setup failed");
1050        revs.diffopt.format_callback = show_filemodify;
1051        DIFF_OPT_SET(&revs.diffopt, RECURSIVE);
1052        while ((commit = get_revision(&revs))) {
1053                if (has_unshown_parent(commit)) {
1054                        add_object_array(&commit->object, NULL, &commits);
1055                }
1056                else {
1057                        handle_commit(commit, &revs);
1058                        handle_tail(&commits, &revs);
1059                }
1060        }
1061
1062        handle_tags_and_duplicates();
1063        handle_deletes();
1064
1065        if (export_filename && lastimportid != last_idnum)
1066                export_marks(export_filename);
1067
1068        if (use_done_feature)
1069                printf("done\n");
1070
1071        free_refspec(refspecs_nr, refspecs);
1072
1073        return 0;
1074}