git.oblomov.eu Git - git/blob - diffcore-rename.c

   1 /*
   2  * Copyright (C) 2005 Junio C Hamano
   3  */
   4 #include "cache.h"
   5 #include "diff.h"
   6 #include "diffcore.h"
   7 #include "hash.h"
   8 #include "progress.h"
   9
  10 /* Table of rename/copy destinations */
  11
  12 static struct diff_rename_dst {
  13         struct diff_filespec *two;
  14         struct diff_filepair *pair;
  15 } *rename_dst;
  16 static int rename_dst_nr, rename_dst_alloc;
  17
  18 static struct diff_rename_dst *locate_rename_dst(struct diff_filespec *two,
  19                                                  int insert_ok)
  20 {
  21         int first, last;
  22
  23         first = 0;
  24         last = rename_dst_nr;
  25         while (last > first) {
  26                 int next = (last + first) >> 1;
  27                 struct diff_rename_dst *dst = &(rename_dst[next]);
  28                 int cmp = strcmp(two->path, dst->two->path);
  29                 if (!cmp)
  30                         return dst;
  31                 if (cmp < 0) {
  32                         last = next;
  33                         continue;
  34                 }
  35                 first = next+1;
  36         }
  37         /* not found */
  38         if (!insert_ok)
  39                 return NULL;
  40         /* insert to make it at "first" */
  41         ALLOC_GROW(rename_dst, rename_dst_nr + 1, rename_dst_alloc);
  42         rename_dst_nr++;
  43         if (first < rename_dst_nr)
  44                 memmove(rename_dst + first + 1, rename_dst + first,
  45                         (rename_dst_nr - first - 1) * sizeof(*rename_dst));
  46         rename_dst[first].two = alloc_filespec(two->path);
  47         fill_filespec(rename_dst[first].two, two->sha1, two->sha1_valid, two->mode);
  48         rename_dst[first].pair = NULL;
  49         return &(rename_dst[first]);
  50 }
  51
  52 /* Table of rename/copy src files */
  53 static struct diff_rename_src {
  54         struct diff_filepair *p;
  55         unsigned short score; /* to remember the break score */
  56 } *rename_src;
  57 static int rename_src_nr, rename_src_alloc;
  58
  59 static struct diff_rename_src *register_rename_src(struct diff_filepair *p)
  60 {
  61         int first, last;
  62         struct diff_filespec *one = p->one;
  63         unsigned short score = p->score;
  64
  65         first = 0;
  66         last = rename_src_nr;
  67         while (last > first) {
  68                 int next = (last + first) >> 1;
  69                 struct diff_rename_src *src = &(rename_src[next]);
  70                 int cmp = strcmp(one->path, src->p->one->path);
  71                 if (!cmp)
  72                         return src;
  73                 if (cmp < 0) {
  74                         last = next;
  75                         continue;
  76                 }
  77                 first = next+1;
  78         }
  79
  80         /* insert to make it at "first" */
  81         ALLOC_GROW(rename_src, rename_src_nr + 1, rename_src_alloc);
  82         rename_src_nr++;
  83         if (first < rename_src_nr)
  84                 memmove(rename_src + first + 1, rename_src + first,
  85                         (rename_src_nr - first - 1) * sizeof(*rename_src));
  86         rename_src[first].p = p;
  87         rename_src[first].score = score;
  88         return &(rename_src[first]);
  89 }
  90
  91 static int basename_same(struct diff_filespec *src, struct diff_filespec *dst)
  92 {
  93         int src_len = strlen(src->path), dst_len = strlen(dst->path);
  94         while (src_len && dst_len) {
  95                 char c1 = src->path[--src_len];
  96                 char c2 = dst->path[--dst_len];
  97                 if (c1 != c2)
  98                         return 0;
  99                 if (c1 == '/')
 100                         return 1;
 101         }
 102         return (!src_len || src->path[src_len - 1] == '/') &&
 103                 (!dst_len || dst->path[dst_len - 1] == '/');
 104 }
 105
 106 struct diff_score {
 107         int src; /* index in rename_src */
 108         int dst; /* index in rename_dst */
 109         unsigned short score;
 110         short name_score;
 111 };
 112
 113 static int estimate_similarity(struct diff_filespec *src,
 114                                struct diff_filespec *dst,
 115                                int minimum_score)
 116 {
 117         /* src points at a file that existed in the original tree (or
 118          * optionally a file in the destination tree) and dst points
 119          * at a newly created file.  They may be quite similar, in which
 120          * case we want to say src is renamed to dst or src is copied into
 121          * dst, and then some edit has been applied to dst.
 122          *
 123          * Compare them and return how similar they are, representing
 124          * the score as an integer between 0 and MAX_SCORE.
 125          *
 126          * When there is an exact match, it is considered a better
 127          * match than anything else; the destination does not even
 128          * call into this function in that case.
 129          */
 130         unsigned long max_size, delta_size, base_size, src_copied, literal_added;
 131         unsigned long delta_limit;
 132         int score;
 133
 134         /* We deal only with regular files.  Symlink renames are handled
 135          * only when they are exact matches --- in other words, no edits
 136          * after renaming.
 137          */
 138         if (!S_ISREG(src->mode) || !S_ISREG(dst->mode))
 139                 return 0;
 140
 141         /*
 142          * Need to check that source and destination sizes are
 143          * filled in before comparing them.
 144          *
 145          * If we already have "cnt_data" filled in, we know it's
 146          * all good (avoid checking the size for zero, as that
 147          * is a possible size - we really should have a flag to
 148          * say whether the size is valid or not!)
 149          */
 150         if (!src->cnt_data && diff_populate_filespec(src, 1))
 151                 return 0;
 152         if (!dst->cnt_data && diff_populate_filespec(dst, 1))
 153                 return 0;
 154
 155         max_size = ((src->size > dst->size) ? src->size : dst->size);
 156         base_size = ((src->size < dst->size) ? src->size : dst->size);
 157         delta_size = max_size - base_size;
 158
 159         /* We would not consider edits that change the file size so
 160          * drastically.  delta_size must be smaller than
 161          * (MAX_SCORE-minimum_score)/MAX_SCORE * min(src->size, dst->size).
 162          *
 163          * Note that base_size == 0 case is handled here already
 164          * and the final score computation below would not have a
 165          * divide-by-zero issue.
 166          */
 167         if (max_size * (MAX_SCORE-minimum_score) < delta_size * MAX_SCORE)
 168                 return 0;
 169
 170         if (!src->cnt_data && diff_populate_filespec(src, 0))
 171                 return 0;
 172         if (!dst->cnt_data && diff_populate_filespec(dst, 0))
 173                 return 0;
 174
 175         delta_limit = (unsigned long)
 176                 (base_size * (MAX_SCORE-minimum_score) / MAX_SCORE);
 177         if (diffcore_count_changes(src, dst,
 178                                    &src->cnt_data, &dst->cnt_data,
 179                                    delta_limit,
 180                                    &src_copied, &literal_added))
 181                 return 0;
 182
 183         /* How similar are they?
 184          * what percentage of material in dst are from source?
 185          */
 186         if (!dst->size)
 187                 score = 0; /* should not happen */
 188         else
 189                 score = (int)(src_copied * MAX_SCORE / max_size);
 190         return score;
 191 }
 192
 193 static void record_rename_pair(int dst_index, int src_index, int score)
 194 {
 195         struct diff_filespec *src, *dst;
 196         struct diff_filepair *dp;
 197
 198         if (rename_dst[dst_index].pair)
 199                 die("internal error: dst already matched.");
 200
 201         src = rename_src[src_index].p->one;
 202         src->rename_used++;
 203         src->count++;
 204
 205         dst = rename_dst[dst_index].two;
 206         dst->count++;
 207
 208         dp = diff_queue(NULL, src, dst);
 209         dp->renamed_pair = 1;
 210         if (!strcmp(src->path, dst->path))
 211                 dp->score = rename_src[src_index].score;
 212         else
 213                 dp->score = score;
 214         rename_dst[dst_index].pair = dp;
 215 }
 216
 217 /*
 218  * We sort the rename similarity matrix with the score, in descending
 219  * order (the most similar first).
 220  */
 221 static int score_compare(const void *a_, const void *b_)
 222 {
 223         const struct diff_score *a = a_, *b = b_;
 224
 225         /* sink the unused ones to the bottom */
 226         if (a->dst < 0)
 227                 return (0 <= b->dst);
 228         else if (b->dst < 0)
 229                 return -1;
 230
 231         if (a->score == b->score)
 232                 return b->name_score - a->name_score;
 233
 234         return b->score - a->score;
 235 }
 236
 237 struct file_similarity {
 238         int src_dst, index;
 239         struct diff_filespec *filespec;
 240         struct file_similarity *next;
 241 };
 242
 243 static int find_identical_files(struct file_similarity *src,
 244                                 struct file_similarity *dst,
 245                                 struct diff_options *options)
 246 {
 247         int renames = 0;
 248
 249         /*
 250          * Walk over all the destinations ...
 251          */
 252         do {
 253                 struct diff_filespec *target = dst->filespec;
 254                 struct file_similarity *p, *best;
 255                 int i = 100, best_score = -1;
 256
 257                 /*
 258                  * .. to find the best source match
 259                  */
 260                 best = NULL;
 261                 for (p = src; p; p = p->next) {
 262                         int score;
 263                         struct diff_filespec *source = p->filespec;
 264
 265                         /* False hash collision? */
 266                         if (hashcmp(source->sha1, target->sha1))
 267                                 continue;
 268                         /* Non-regular files? If so, the modes must match! */
 269                         if (!S_ISREG(source->mode) || !S_ISREG(target->mode)) {
 270                                 if (source->mode != target->mode)
 271                                         continue;
 272                         }
 273                         /* Give higher scores to sources that haven't been used already */
 274                         score = !source->rename_used;
 275                         if (source->rename_used && options->detect_rename != DIFF_DETECT_COPY)
 276                                 continue;
 277                         score += basename_same(source, target);
 278                         if (score > best_score) {
 279                                 best = p;
 280                                 best_score = score;
 281                                 if (score == 2)
 282                                         break;
 283                         }
 284
 285                         /* Too many identical alternatives? Pick one */
 286                         if (!--i)
 287                                 break;
 288                 }
 289                 if (best) {
 290                         record_rename_pair(dst->index, best->index, MAX_SCORE);
 291                         renames++;
 292                 }
 293         } while ((dst = dst->next) != NULL);
 294         return renames;
 295 }
 296
 297 static void free_similarity_list(struct file_similarity *p)
 298 {
 299         while (p) {
 300                 struct file_similarity *entry = p;
 301                 p = p->next;
 302                 free(entry);
 303         }
 304 }
 305
 306 static int find_same_files(void *ptr, void *data)
 307 {
 308         int ret;
 309         struct file_similarity *p = ptr;
 310         struct file_similarity *src = NULL, *dst = NULL;
 311         struct diff_options *options = data;
 312
 313         /* Split the hash list up into sources and destinations */
 314         do {
 315                 struct file_similarity *entry = p;
 316                 p = p->next;
 317                 if (entry->src_dst < 0) {
 318                         entry->next = src;
 319                         src = entry;
 320                 } else {
 321                         entry->next = dst;
 322                         dst = entry;
 323                 }
 324         } while (p);
 325
 326         /*
 327          * If we have both sources *and* destinations, see if
 328          * we can match them up
 329          */
 330         ret = (src && dst) ? find_identical_files(src, dst, options) : 0;
 331
 332         /* Free the hashes and return the number of renames found */
 333         free_similarity_list(src);
 334         free_similarity_list(dst);
 335         return ret;
 336 }
 337
 338 static unsigned int hash_filespec(struct diff_filespec *filespec)
 339 {
 340         unsigned int hash;
 341         if (!filespec->sha1_valid) {
 342                 if (diff_populate_filespec(filespec, 0))
 343                         return 0;
 344                 hash_sha1_file(filespec->data, filespec->size, "blob", filespec->sha1);
 345         }
 346         memcpy(&hash, filespec->sha1, sizeof(hash));
 347         return hash;
 348 }
 349
 350 static void insert_file_table(struct hash_table *table, int src_dst, int index, struct diff_filespec *filespec)
 351 {
 352         void **pos;
 353         unsigned int hash;
 354         struct file_similarity *entry = xmalloc(sizeof(*entry));
 355
 356         entry->src_dst = src_dst;
 357         entry->index = index;
 358         entry->filespec = filespec;
 359         entry->next = NULL;
 360
 361         hash = hash_filespec(filespec);
 362         pos = insert_hash(hash, entry, table);
 363
 364         /* We already had an entry there? */
 365         if (pos) {
 366                 entry->next = *pos;
 367                 *pos = entry;
 368         }
 369 }
 370
 371 /*
 372  * Find exact renames first.
 373  *
 374  * The first round matches up the up-to-date entries,
 375  * and then during the second round we try to match
 376  * cache-dirty entries as well.
 377  */
 378 static int find_exact_renames(struct diff_options *options)
 379 {
 380         int i;
 381         struct hash_table file_table;
 382
 383         init_hash(&file_table);
 384         preallocate_hash(&file_table, rename_src_nr + rename_dst_nr);
 385         for (i = 0; i < rename_src_nr; i++)
 386                 insert_file_table(&file_table, -1, i, rename_src[i].p->one);
 387
 388         for (i = 0; i < rename_dst_nr; i++)
 389                 insert_file_table(&file_table, 1, i, rename_dst[i].two);
 390
 391         /* Find the renames */
 392         i = for_each_hash(&file_table, find_same_files, options);
 393
 394         /* .. and free the hash data structure */
 395         free_hash(&file_table);
 396
 397         return i;
 398 }
 399
 400 #define NUM_CANDIDATE_PER_DST 4
 401 static void record_if_better(struct diff_score m[], struct diff_score *o)
 402 {
 403         int i, worst;
 404
 405         /* find the worst one */
 406         worst = 0;
 407         for (i = 1; i < NUM_CANDIDATE_PER_DST; i++)
 408                 if (score_compare(&m[i], &m[worst]) > 0)
 409                         worst = i;
 410
 411         /* is it better than the worst one? */
 412         if (score_compare(&m[worst], o) > 0)
 413                 m[worst] = *o;
 414 }
 415
 416 /*
 417  * Returns:
 418  * 0 if we are under the limit;
 419  * 1 if we need to disable inexact rename detection;
 420  * 2 if we would be under the limit if we were given -C instead of -C -C.
 421  */
 422 static int too_many_rename_candidates(int num_create,
 423                                       struct diff_options *options)
 424 {
 425         int rename_limit = options->rename_limit;
 426         int num_src = rename_src_nr;
 427         int i;
 428
 429         options->needed_rename_limit = 0;
 430
 431         /*
 432          * This basically does a test for the rename matrix not
 433          * growing larger than a "rename_limit" square matrix, ie:
 434          *
 435          *    num_create * num_src > rename_limit * rename_limit
 436          *
 437          * but handles the potential overflow case specially (and we
 438          * assume at least 32-bit integers)
 439          */
 440         if (rename_limit <= 0 || rename_limit > 32767)
 441                 rename_limit = 32767;
 442         if ((num_create <= rename_limit || num_src <= rename_limit) &&
 443             (num_create * num_src <= rename_limit * rename_limit))
 444                 return 0;
 445
 446         options->needed_rename_limit =
 447                 num_src > num_create ? num_src : num_create;
 448
 449         /* Are we running under -C -C? */
 450         if (!DIFF_OPT_TST(options, FIND_COPIES_HARDER))
 451                 return 1;
 452
 453         /* Would we bust the limit if we were running under -C? */
 454         for (num_src = i = 0; i < rename_src_nr; i++) {
 455                 if (diff_unmodified_pair(rename_src[i].p))
 456                         continue;
 457                 num_src++;
 458         }
 459         if ((num_create <= rename_limit || num_src <= rename_limit) &&
 460             (num_create * num_src <= rename_limit * rename_limit))
 461                 return 2;
 462         return 1;
 463 }
 464
 465 static int find_renames(struct diff_score *mx, int dst_cnt, int minimum_score, int copies)
 466 {
 467         int count = 0, i;
 468
 469         for (i = 0; i < dst_cnt * NUM_CANDIDATE_PER_DST; i++) {
 470                 struct diff_rename_dst *dst;
 471
 472                 if ((mx[i].dst < 0) ||
 473                     (mx[i].score < minimum_score))
 474                         break; /* there is no more usable pair. */
 475                 dst = &rename_dst[mx[i].dst];
 476                 if (dst->pair)
 477                         continue; /* already done, either exact or fuzzy. */
 478                 if (!copies && rename_src[mx[i].src].p->one->rename_used)
 479                         continue;
 480                 record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
 481                 count++;
 482         }
 483         return count;
 484 }
 485
 486 void diffcore_rename(struct diff_options *options)
 487 {
 488         int detect_rename = options->detect_rename;
 489         int minimum_score = options->rename_score;
 490         struct diff_queue_struct *q = &diff_queued_diff;
 491         struct diff_queue_struct outq;
 492         struct diff_score *mx;
 493         int i, j, rename_count, skip_unmodified = 0;
 494         int num_create, dst_cnt;
 495         struct progress *progress = NULL;
 496
 497         if (!minimum_score)
 498                 minimum_score = DEFAULT_RENAME_SCORE;
 499
 500         for (i = 0; i < q->nr; i++) {
 501                 struct diff_filepair *p = q->queue[i];
 502                 if (!DIFF_FILE_VALID(p->one)) {
 503                         if (!DIFF_FILE_VALID(p->two))
 504                                 continue; /* unmerged */
 505                         else if (options->single_follow &&
 506                                  strcmp(options->single_follow, p->two->path))
 507                                 continue; /* not interested */
 508                         else if (!DIFF_OPT_TST(options, RENAME_EMPTY) &&
 509                                  is_empty_blob_sha1(p->two->sha1))
 510                                 continue;
 511                         else
 512                                 locate_rename_dst(p->two, 1);
 513                 }
 514                 else if (!DIFF_OPT_TST(options, RENAME_EMPTY) &&
 515                          is_empty_blob_sha1(p->one->sha1))
 516                         continue;
 517                 else if (!DIFF_PAIR_UNMERGED(p) && !DIFF_FILE_VALID(p->two)) {
 518                         /*
 519                          * If the source is a broken "delete", and
 520                          * they did not really want to get broken,
 521                          * that means the source actually stays.
 522                          * So we increment the "rename_used" score
 523                          * by one, to indicate ourselves as a user
 524                          */
 525                         if (p->broken_pair && !p->score)
 526                                 p->one->rename_used++;
 527                         register_rename_src(p);
 528                 }
 529                 else if (detect_rename == DIFF_DETECT_COPY) {
 530                         /*
 531                          * Increment the "rename_used" score by
 532                          * one, to indicate ourselves as a user.
 533                          */
 534                         p->one->rename_used++;
 535                         register_rename_src(p);
 536                 }
 537         }
 538         if (rename_dst_nr == 0 || rename_src_nr == 0)
 539                 goto cleanup; /* nothing to do */
 540
 541         /*
 542          * We really want to cull the candidates list early
 543          * with cheap tests in order to avoid doing deltas.
 544          */
 545         rename_count = find_exact_renames(options);
 546
 547         /* Did we only want exact renames? */
 548         if (minimum_score == MAX_SCORE)
 549                 goto cleanup;
 550
 551         /*
 552          * Calculate how many renames are left (but all the source
 553          * files still remain as options for rename/copies!)
 554          */
 555         num_create = (rename_dst_nr - rename_count);
 556
 557         /* All done? */
 558         if (!num_create)
 559                 goto cleanup;
 560
 561         switch (too_many_rename_candidates(num_create, options)) {
 562         case 1:
 563                 goto cleanup;
 564         case 2:
 565                 options->degraded_cc_to_c = 1;
 566                 skip_unmodified = 1;
 567                 break;
 568         default:
 569                 break;
 570         }
 571
 572         if (options->show_rename_progress) {
 573                 progress = start_progress_delay(
 574                                 "Performing inexact rename detection",
 575                                 rename_dst_nr * rename_src_nr, 50, 1);
 576         }
 577
 578         mx = xcalloc(num_create * NUM_CANDIDATE_PER_DST, sizeof(*mx));
 579         for (dst_cnt = i = 0; i < rename_dst_nr; i++) {
 580                 struct diff_filespec *two = rename_dst[i].two;
 581                 struct diff_score *m;
 582
 583                 if (rename_dst[i].pair)
 584                         continue; /* dealt with exact match already. */
 585
 586                 m = &mx[dst_cnt * NUM_CANDIDATE_PER_DST];
 587                 for (j = 0; j < NUM_CANDIDATE_PER_DST; j++)
 588                         m[j].dst = -1;
 589
 590                 for (j = 0; j < rename_src_nr; j++) {
 591                         struct diff_filespec *one = rename_src[j].p->one;
 592                         struct diff_score this_src;
 593
 594                         if (skip_unmodified &&
 595                             diff_unmodified_pair(rename_src[j].p))
 596                                 continue;
 597
 598                         this_src.score = estimate_similarity(one, two,
 599                                                              minimum_score);
 600                         this_src.name_score = basename_same(one, two);
 601                         this_src.dst = i;
 602                         this_src.src = j;
 603                         record_if_better(m, &this_src);
 604                         /*
 605                          * Once we run estimate_similarity,
 606                          * We do not need the text anymore.
 607                          */
 608                         diff_free_filespec_blob(one);
 609                         diff_free_filespec_blob(two);
 610                 }
 611                 dst_cnt++;
 612                 display_progress(progress, (i+1)*rename_src_nr);
 613         }
 614         stop_progress(&progress);
 615
 616         /* cost matrix sorted by most to least similar pair */
 617         qsort(mx, dst_cnt * NUM_CANDIDATE_PER_DST, sizeof(*mx), score_compare);
 618
 619         rename_count += find_renames(mx, dst_cnt, minimum_score, 0);
 620         if (detect_rename == DIFF_DETECT_COPY)
 621                 rename_count += find_renames(mx, dst_cnt, minimum_score, 1);
 622         free(mx);
 623
 624  cleanup:
 625         /* At this point, we have found some renames and copies and they
 626          * are recorded in rename_dst.  The original list is still in *q.
 627          */
 628         DIFF_QUEUE_CLEAR(&outq);
 629         for (i = 0; i < q->nr; i++) {
 630                 struct diff_filepair *p = q->queue[i];
 631                 struct diff_filepair *pair_to_free = NULL;
 632
 633                 if (DIFF_PAIR_UNMERGED(p)) {
 634                         diff_q(&outq, p);
 635                 }
 636                 else if (!DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
 637                         /*
 638                          * Creation
 639                          *
 640                          * We would output this create record if it has
 641                          * not been turned into a rename/copy already.
 642                          */
 643                         struct diff_rename_dst *dst =
 644                                 locate_rename_dst(p->two, 0);
 645                         if (dst && dst->pair) {
 646                                 diff_q(&outq, dst->pair);
 647                                 pair_to_free = p;
 648                         }
 649                         else
 650                                 /* no matching rename/copy source, so
 651                                  * record this as a creation.
 652                                  */
 653                                 diff_q(&outq, p);
 654                 }
 655                 else if (DIFF_FILE_VALID(p->one) && !DIFF_FILE_VALID(p->two)) {
 656                         /*
 657                          * Deletion
 658                          *
 659                          * We would output this delete record if:
 660                          *
 661                          * (1) this is a broken delete and the counterpart
 662                          *     broken create remains in the output; or
 663                          * (2) this is not a broken delete, and rename_dst
 664                          *     does not have a rename/copy to move p->one->path
 665                          *     out of existence.
 666                          *
 667                          * Otherwise, the counterpart broken create
 668                          * has been turned into a rename-edit; or
 669                          * delete did not have a matching create to
 670                          * begin with.
 671                          */
 672                         if (DIFF_PAIR_BROKEN(p)) {
 673                                 /* broken delete */
 674                                 struct diff_rename_dst *dst =
 675                                         locate_rename_dst(p->one, 0);
 676                                 if (dst && dst->pair)
 677                                         /* counterpart is now rename/copy */
 678                                         pair_to_free = p;
 679                         }
 680                         else {
 681                                 if (p->one->rename_used)
 682                                         /* this path remains */
 683                                         pair_to_free = p;
 684                         }
 685
 686                         if (pair_to_free)
 687                                 ;
 688                         else
 689                                 diff_q(&outq, p);
 690                 }
 691                 else if (!diff_unmodified_pair(p))
 692                         /* all the usual ones need to be kept */
 693                         diff_q(&outq, p);
 694                 else
 695                         /* no need to keep unmodified pairs */
 696                         pair_to_free = p;
 697
 698                 if (pair_to_free)
 699                         diff_free_filepair(pair_to_free);
 700         }
 701         diff_debug_queue("done copying original", &outq);
 702
 703         free(q->queue);
 704         *q = outq;
 705         diff_debug_queue("done collapsing", q);
 706
 707         for (i = 0; i < rename_dst_nr; i++)
 708                 free_filespec(rename_dst[i].two);
 709
 710         free(rename_dst);
 711         rename_dst = NULL;
 712         rename_dst_nr = rename_dst_alloc = 0;
 713         free(rename_src);
 714         rename_src = NULL;
 715         rename_src_nr = rename_src_alloc = 0;
 716         return;
 717 }