hashmap: improve struct hashmap member documentation
[git/git.git] / diffcore-rename.c
CommitLineData
427dcb4b
JH
1/*
2 * Copyright (C) 2005 Junio C Hamano
3 */
4#include "cache.h"
5#include "diff.h"
6#include "diffcore.h"
f79d9c58 7#include "hashmap.h"
3ac942d4 8#include "progress.h"
427dcb4b 9
25d5ea41
JH
10/* Table of rename/copy destinations */
11
12static struct diff_rename_dst {
13 struct diff_filespec *two;
14 struct diff_filepair *pair;
15} *rename_dst;
16static int rename_dst_nr, rename_dst_alloc;
427dcb4b 17
25d5ea41
JH
18static struct diff_rename_dst *locate_rename_dst(struct diff_filespec *two,
19 int insert_ok)
427dcb4b 20{
25d5ea41
JH
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" */
337ce247 41 ALLOC_GROW(rename_dst, rename_dst_nr + 1, rename_dst_alloc);
25d5ea41
JH
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));
5098bafb 46 rename_dst[first].two = alloc_filespec(two->path);
e5450100 47 fill_filespec(rename_dst[first].two, two->sha1, two->sha1_valid, two->mode);
25d5ea41
JH
48 rename_dst[first].pair = NULL;
49 return &(rename_dst[first]);
427dcb4b
JH
50}
51
15d061b4 52/* Table of rename/copy src files */
25d5ea41 53static struct diff_rename_src {
e88d6bc6 54 struct diff_filepair *p;
fc580719 55 unsigned short score; /* to remember the break score */
25d5ea41
JH
56} *rename_src;
57static int rename_src_nr, rename_src_alloc;
427dcb4b 58
e88d6bc6 59static struct diff_rename_src *register_rename_src(struct diff_filepair *p)
25d5ea41
JH
60{
61 int first, last;
e88d6bc6
JH
62 struct diff_filespec *one = p->one;
63 unsigned short score = p->score;
25d5ea41
JH
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]);
e88d6bc6 70 int cmp = strcmp(one->path, src->p->one->path);
25d5ea41
JH
71 if (!cmp)
72 return src;
73 if (cmp < 0) {
74 last = next;
75 continue;
76 }
77 first = next+1;
78 }
15d061b4 79
25d5ea41 80 /* insert to make it at "first" */
337ce247 81 ALLOC_GROW(rename_src, rename_src_nr + 1, rename_src_alloc);
25d5ea41
JH
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));
e88d6bc6 86 rename_src[first].p = p;
fc580719 87 rename_src[first].score = score;
25d5ea41 88 return &(rename_src[first]);
427dcb4b
JH
89}
90
0ce39643
JS
91static 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
427dcb4b 106struct diff_score {
25d5ea41
JH
107 int src; /* index in rename_src */
108 int dst; /* index in rename_dst */
6d24ad97
JH
109 unsigned short score;
110 short name_score;
427dcb4b
JH
111};
112
113static 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
f0c6b2a2
JH
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.
427dcb4b 129 */
90bd932c 130 unsigned long max_size, delta_size, base_size, src_copied, literal_added;
75c660ac 131 unsigned long delta_limit;
427dcb4b
JH
132 int score;
133
60896c7b
JH
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
81ac051d
LT
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 */
885c716f 150 if (!src->cnt_data && diff_populate_filespec(src, 1))
81ac051d 151 return 0;
885c716f 152 if (!dst->cnt_data && diff_populate_filespec(dst, 1))
81ac051d
LT
153 return 0;
154
90bd932c 155 max_size = ((src->size > dst->size) ? src->size : dst->size);
58b103f5 156 base_size = ((src->size < dst->size) ? src->size : dst->size);
90bd932c 157 delta_size = max_size - base_size;
427dcb4b 158
58b103f5
JH
159 /* We would not consider edits that change the file size so
160 * drastically. delta_size must be smaller than
cd1870ed 161 * (MAX_SCORE-minimum_score)/MAX_SCORE * min(src->size, dst->size).
f0c6b2a2 162 *
58b103f5
JH
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.
427dcb4b 166 */
3a4d6769 167 if (max_size * (MAX_SCORE-minimum_score) < delta_size * MAX_SCORE)
427dcb4b
JH
168 return 0;
169
885c716f
BS
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
dc49cd76
SP
175 delta_limit = (unsigned long)
176 (base_size * (MAX_SCORE-minimum_score) / MAX_SCORE);
d8c3d03a 177 if (diffcore_count_changes(src, dst,
c06c7966 178 &src->cnt_data, &dst->cnt_data,
65416758
JH
179 delta_limit,
180 &src_copied, &literal_added))
85976974 181 return 0;
355e76a4 182
1706306a
JH
183 /* How similar are they?
184 * what percentage of material in dst are from source?
427dcb4b 185 */
90bd932c 186 if (!dst->size)
1706306a 187 score = 0; /* should not happen */
cfc0aef1 188 else
dc49cd76 189 score = (int)(src_copied * MAX_SCORE / max_size);
427dcb4b
JH
190 return score;
191}
192
5098bafb 193static void record_rename_pair(int dst_index, int src_index, int score)
427dcb4b 194{
9fb88419 195 struct diff_filespec *src, *dst;
25d5ea41 196 struct diff_filepair *dp;
f7c1512a 197
25d5ea41
JH
198 if (rename_dst[dst_index].pair)
199 die("internal error: dst already matched.");
427dcb4b 200
e88d6bc6 201 src = rename_src[src_index].p->one;
64479711 202 src->rename_used++;
9fb88419 203 src->count++;
427dcb4b 204
25d5ea41 205 dst = rename_dst[dst_index].two;
9fb88419 206 dst->count++;
427dcb4b 207
9fb88419 208 dp = diff_queue(NULL, src, dst);
ef677686 209 dp->renamed_pair = 1;
fc580719
JH
210 if (!strcmp(src->path, dst->path))
211 dp->score = rename_src[src_index].score;
212 else
213 dp->score = score;
25d5ea41 214 rename_dst[dst_index].pair = dp;
427dcb4b
JH
215}
216
217/*
218 * We sort the rename similarity matrix with the score, in descending
15d061b4 219 * order (the most similar first).
427dcb4b
JH
220 */
221static int score_compare(const void *a_, const void *b_)
222{
223 const struct diff_score *a = a_, *b = b_;
cfc0aef1 224
6d24ad97
JH
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
cfc0aef1
RS
231 if (a->score == b->score)
232 return b->name_score - a->name_score;
233
427dcb4b
JH
234 return b->score - a->score;
235}
236
9027f53c 237struct file_similarity {
f79d9c58 238 struct hashmap_entry entry;
7c85f8ac 239 int index;
9027f53c 240 struct diff_filespec *filespec;
9027f53c
LT
241};
242
48f6407f
KB
243static unsigned int hash_filespec(struct diff_filespec *filespec)
244{
48f6407f
KB
245 if (!filespec->sha1_valid) {
246 if (diff_populate_filespec(filespec, 0))
247 return 0;
248 hash_sha1_file(filespec->data, filespec->size, "blob", filespec->sha1);
249 }
039dc71a 250 return sha1hash(filespec->sha1);
48f6407f
KB
251}
252
f79d9c58 253static int find_identical_files(struct hashmap *srcs,
7c85f8ac 254 int dst_index,
11f944dd 255 struct diff_options *options)
9027f53c
LT
256{
257 int renames = 0;
258
7c85f8ac 259 struct diff_filespec *target = rename_dst[dst_index].two;
f79d9c58 260 struct file_similarity *p, *best, dst;
48f6407f
KB
261 int i = 100, best_score = -1;
262
263 /*
7c85f8ac 264 * Find the best source match for specified destination.
48f6407f
KB
265 */
266 best = NULL;
f79d9c58
KB
267 hashmap_entry_init(&dst, hash_filespec(target));
268 for (p = hashmap_get(srcs, &dst, NULL); p; p = hashmap_get_next(srcs, p)) {
48f6407f
KB
269 int score;
270 struct diff_filespec *source = p->filespec;
271
272 /* False hash collision? */
273 if (hashcmp(source->sha1, target->sha1))
274 continue;
275 /* Non-regular files? If so, the modes must match! */
276 if (!S_ISREG(source->mode) || !S_ISREG(target->mode)) {
277 if (source->mode != target->mode)
0940e5f2 278 continue;
9027f53c 279 }
48f6407f
KB
280 /* Give higher scores to sources that haven't been used already */
281 score = !source->rename_used;
282 if (source->rename_used && options->detect_rename != DIFF_DETECT_COPY)
283 continue;
284 score += basename_same(source, target);
285 if (score > best_score) {
286 best = p;
287 best_score = score;
288 if (score == 2)
289 break;
9027f53c 290 }
48f6407f
KB
291
292 /* Too many identical alternatives? Pick one */
293 if (!--i)
294 break;
295 }
296 if (best) {
7c85f8ac 297 record_rename_pair(dst_index, best->index, MAX_SCORE);
48f6407f
KB
298 renames++;
299 }
9027f53c
LT
300 return renames;
301}
302
f79d9c58 303static void insert_file_table(struct hashmap *table, int index, struct diff_filespec *filespec)
9027f53c 304{
9027f53c
LT
305 struct file_similarity *entry = xmalloc(sizeof(*entry));
306
9027f53c
LT
307 entry->index = index;
308 entry->filespec = filespec;
9027f53c 309
f79d9c58
KB
310 hashmap_entry_init(entry, hash_filespec(filespec));
311 hashmap_add(table, entry);
9027f53c
LT
312}
313
cb1491b6
LT
314/*
315 * Find exact renames first.
316 *
317 * The first round matches up the up-to-date entries,
318 * and then during the second round we try to match
319 * cache-dirty entries as well.
cb1491b6 320 */
11f944dd 321static int find_exact_renames(struct diff_options *options)
cb1491b6 322{
7c85f8ac 323 int i, renames = 0;
f79d9c58 324 struct hashmap file_table;
cb1491b6 325
7c85f8ac 326 /* Add all sources to the hash table */
f79d9c58 327 hashmap_init(&file_table, NULL, rename_src_nr);
9027f53c 328 for (i = 0; i < rename_src_nr; i++)
7c85f8ac 329 insert_file_table(&file_table, i, rename_src[i].p->one);
9027f53c 330
7c85f8ac 331 /* Walk the destinations and find best source match */
9027f53c 332 for (i = 0; i < rename_dst_nr; i++)
7c85f8ac 333 renames += find_identical_files(&file_table, i, options);
9027f53c 334
f79d9c58
KB
335 /* Free the hash data structure and entries */
336 hashmap_free(&file_table, 1);
9027f53c 337
7c85f8ac 338 return renames;
cb1491b6
LT
339}
340
6d24ad97
JH
341#define NUM_CANDIDATE_PER_DST 4
342static void record_if_better(struct diff_score m[], struct diff_score *o)
343{
344 int i, worst;
345
346 /* find the worst one */
347 worst = 0;
348 for (i = 1; i < NUM_CANDIDATE_PER_DST; i++)
349 if (score_compare(&m[i], &m[worst]) > 0)
350 worst = i;
351
352 /* is it better than the worst one? */
353 if (score_compare(&m[worst], o) > 0)
354 m[worst] = *o;
355}
356
f31027c9
JH
357/*
358 * Returns:
359 * 0 if we are under the limit;
360 * 1 if we need to disable inexact rename detection;
361 * 2 if we would be under the limit if we were given -C instead of -C -C.
362 */
9d8a5a50
JH
363static int too_many_rename_candidates(int num_create,
364 struct diff_options *options)
365{
366 int rename_limit = options->rename_limit;
367 int num_src = rename_src_nr;
f31027c9 368 int i;
9d8a5a50
JH
369
370 options->needed_rename_limit = 0;
371
372 /*
373 * This basically does a test for the rename matrix not
374 * growing larger than a "rename_limit" square matrix, ie:
375 *
376 * num_create * num_src > rename_limit * rename_limit
377 *
378 * but handles the potential overflow case specially (and we
379 * assume at least 32-bit integers)
380 */
381 if (rename_limit <= 0 || rename_limit > 32767)
382 rename_limit = 32767;
383 if ((num_create <= rename_limit || num_src <= rename_limit) &&
384 (num_create * num_src <= rename_limit * rename_limit))
385 return 0;
386
387 options->needed_rename_limit =
388 num_src > num_create ? num_src : num_create;
f31027c9
JH
389
390 /* Are we running under -C -C? */
391 if (!DIFF_OPT_TST(options, FIND_COPIES_HARDER))
392 return 1;
393
394 /* Would we bust the limit if we were running under -C? */
395 for (num_src = i = 0; i < rename_src_nr; i++) {
396 if (diff_unmodified_pair(rename_src[i].p))
397 continue;
398 num_src++;
399 }
400 if ((num_create <= rename_limit || num_src <= rename_limit) &&
401 (num_create * num_src <= rename_limit * rename_limit))
402 return 2;
9d8a5a50
JH
403 return 1;
404}
405
0940e5f2
LT
406static int find_renames(struct diff_score *mx, int dst_cnt, int minimum_score, int copies)
407{
408 int count = 0, i;
409
410 for (i = 0; i < dst_cnt * NUM_CANDIDATE_PER_DST; i++) {
411 struct diff_rename_dst *dst;
412
413 if ((mx[i].dst < 0) ||
414 (mx[i].score < minimum_score))
415 break; /* there is no more usable pair. */
416 dst = &rename_dst[mx[i].dst];
417 if (dst->pair)
418 continue; /* already done, either exact or fuzzy. */
e88d6bc6 419 if (!copies && rename_src[mx[i].src].p->one->rename_used)
0940e5f2
LT
420 continue;
421 record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
422 count++;
423 }
424 return count;
425}
426
8082d8d3 427void diffcore_rename(struct diff_options *options)
427dcb4b 428{
8082d8d3
JH
429 int detect_rename = options->detect_rename;
430 int minimum_score = options->rename_score;
38c6f780 431 struct diff_queue_struct *q = &diff_queued_diff;
5098bafb 432 struct diff_queue_struct outq;
427dcb4b 433 struct diff_score *mx;
f31027c9 434 int i, j, rename_count, skip_unmodified = 0;
dabdbee1 435 int num_create, dst_cnt;
3ac942d4 436 struct progress *progress = NULL;
427dcb4b 437
26dee0ad 438 if (!minimum_score)
f345b0a0 439 minimum_score = DEFAULT_RENAME_SCORE;
427dcb4b 440
427dcb4b 441 for (i = 0; i < q->nr; i++) {
52e95789 442 struct diff_filepair *p = q->queue[i];
2f3f8b21 443 if (!DIFF_FILE_VALID(p->one)) {
81e50eab 444 if (!DIFF_FILE_VALID(p->two))
60896c7b 445 continue; /* unmerged */
2f3f8b21
JH
446 else if (options->single_follow &&
447 strcmp(options->single_follow, p->two->path))
448 continue; /* not interested */
90d43b07
JK
449 else if (!DIFF_OPT_TST(options, RENAME_EMPTY) &&
450 is_empty_blob_sha1(p->two->sha1))
451 continue;
427dcb4b 452 else
25d5ea41 453 locate_rename_dst(p->two, 1);
2f3f8b21 454 }
90d43b07
JK
455 else if (!DIFF_OPT_TST(options, RENAME_EMPTY) &&
456 is_empty_blob_sha1(p->one->sha1))
457 continue;
d7c9bf22 458 else if (!DIFF_PAIR_UNMERGED(p) && !DIFF_FILE_VALID(p->two)) {
64479711
LT
459 /*
460 * If the source is a broken "delete", and
2210100a
JH
461 * they did not really want to get broken,
462 * that means the source actually stays.
64479711
LT
463 * So we increment the "rename_used" score
464 * by one, to indicate ourselves as a user
465 */
466 if (p->broken_pair && !p->score)
467 p->one->rename_used++;
e88d6bc6 468 register_rename_src(p);
64479711
LT
469 }
470 else if (detect_rename == DIFF_DETECT_COPY) {
471 /*
472 * Increment the "rename_used" score by
473 * one, to indicate ourselves as a user.
2210100a 474 */
64479711 475 p->one->rename_used++;
e88d6bc6 476 register_rename_src(p);
2210100a 477 }
427dcb4b 478 }
0024a549 479 if (rename_dst_nr == 0 || rename_src_nr == 0)
427dcb4b
JH
480 goto cleanup; /* nothing to do */
481
17559a64
LT
482 /*
483 * We really want to cull the candidates list early
484 * with cheap tests in order to avoid doing deltas.
485 */
11f944dd 486 rename_count = find_exact_renames(options);
17559a64 487
42899ac8
LT
488 /* Did we only want exact renames? */
489 if (minimum_score == MAX_SCORE)
490 goto cleanup;
491
492 /*
493 * Calculate how many renames are left (but all the source
494 * files still remain as options for rename/copies!)
495 */
496 num_create = (rename_dst_nr - rename_count);
42899ac8
LT
497
498 /* All done? */
499 if (!num_create)
500 goto cleanup;
501
f31027c9
JH
502 switch (too_many_rename_candidates(num_create, options)) {
503 case 1:
0024a549 504 goto cleanup;
f31027c9
JH
505 case 2:
506 options->degraded_cc_to_c = 1;
507 skip_unmodified = 1;
508 break;
509 default:
510 break;
511 }
0024a549 512
3ac942d4
JK
513 if (options->show_rename_progress) {
514 progress = start_progress_delay(
754dbc43 515 _("Performing inexact rename detection"),
3ac942d4
JK
516 rename_dst_nr * rename_src_nr, 50, 1);
517 }
518
6d24ad97 519 mx = xcalloc(num_create * NUM_CANDIDATE_PER_DST, sizeof(*mx));
25d5ea41 520 for (dst_cnt = i = 0; i < rename_dst_nr; i++) {
25d5ea41 521 struct diff_filespec *two = rename_dst[i].two;
6d24ad97
JH
522 struct diff_score *m;
523
25d5ea41 524 if (rename_dst[i].pair)
427dcb4b 525 continue; /* dealt with exact match already. */
6d24ad97
JH
526
527 m = &mx[dst_cnt * NUM_CANDIDATE_PER_DST];
528 for (j = 0; j < NUM_CANDIDATE_PER_DST; j++)
529 m[j].dst = -1;
530
25d5ea41 531 for (j = 0; j < rename_src_nr; j++) {
e88d6bc6 532 struct diff_filespec *one = rename_src[j].p->one;
6d24ad97 533 struct diff_score this_src;
f31027c9
JH
534
535 if (skip_unmodified &&
536 diff_unmodified_pair(rename_src[j].p))
537 continue;
538
6d24ad97
JH
539 this_src.score = estimate_similarity(one, two,
540 minimum_score);
541 this_src.name_score = basename_same(one, two);
542 this_src.dst = i;
543 this_src.src = j;
544 record_if_better(m, &this_src);
809809bb
JH
545 /*
546 * Once we run estimate_similarity,
547 * We do not need the text anymore.
548 */
8ae92e63 549 diff_free_filespec_blob(one);
809809bb 550 diff_free_filespec_blob(two);
427dcb4b
JH
551 }
552 dst_cnt++;
3ac942d4 553 display_progress(progress, (i+1)*rename_src_nr);
427dcb4b 554 }
3ac942d4 555 stop_progress(&progress);
6d24ad97 556
427dcb4b 557 /* cost matrix sorted by most to least similar pair */
6d24ad97
JH
558 qsort(mx, dst_cnt * NUM_CANDIDATE_PER_DST, sizeof(*mx), score_compare);
559
0940e5f2
LT
560 rename_count += find_renames(mx, dst_cnt, minimum_score, 0);
561 if (detect_rename == DIFF_DETECT_COPY)
562 rename_count += find_renames(mx, dst_cnt, minimum_score, 1);
427dcb4b 563 free(mx);
427dcb4b 564
15d061b4 565 cleanup:
427dcb4b 566 /* At this point, we have found some renames and copies and they
5098bafb 567 * are recorded in rename_dst. The original list is still in *q.
427dcb4b 568 */
9ca5df90 569 DIFF_QUEUE_CLEAR(&outq);
427dcb4b 570 for (i = 0; i < q->nr; i++) {
25d5ea41 571 struct diff_filepair *p = q->queue[i];
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JH
572 struct diff_filepair *pair_to_free = NULL;
573
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MZ
574 if (DIFF_PAIR_UNMERGED(p)) {
575 diff_q(&outq, p);
576 }
577 else if (!DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) {
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578 /*
579 * Creation
580 *
581 * We would output this create record if it has
582 * not been turned into a rename/copy already.
583 */
584 struct diff_rename_dst *dst =
585 locate_rename_dst(p->two, 0);
586 if (dst && dst->pair) {
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587 diff_q(&outq, dst->pair);
588 pair_to_free = p;
589 }
590 else
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JH
591 /* no matching rename/copy source, so
592 * record this as a creation.
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593 */
594 diff_q(&outq, p);
427dcb4b 595 }
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JH
596 else if (DIFF_FILE_VALID(p->one) && !DIFF_FILE_VALID(p->two)) {
597 /*
598 * Deletion
599 *
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600 * We would output this delete record if:
601 *
602 * (1) this is a broken delete and the counterpart
603 * broken create remains in the output; or
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JH
604 * (2) this is not a broken delete, and rename_dst
605 * does not have a rename/copy to move p->one->path
606 * out of existence.
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JH
607 *
608 * Otherwise, the counterpart broken create
609 * has been turned into a rename-edit; or
610 * delete did not have a matching create to
611 * begin with.
2cd68882 612 */
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JH
613 if (DIFF_PAIR_BROKEN(p)) {
614 /* broken delete */
615 struct diff_rename_dst *dst =
616 locate_rename_dst(p->one, 0);
617 if (dst && dst->pair)
618 /* counterpart is now rename/copy */
619 pair_to_free = p;
620 }
621 else {
64479711 622 if (p->one->rename_used)
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JH
623 /* this path remains */
624 pair_to_free = p;
625 }
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JH
626
627 if (pair_to_free)
628 ;
629 else
630 diff_q(&outq, p);
631 }
25d5ea41 632 else if (!diff_unmodified_pair(p))
15d061b4 633 /* all the usual ones need to be kept */
25d5ea41 634 diff_q(&outq, p);
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JH
635 else
636 /* no need to keep unmodified pairs */
637 pair_to_free = p;
638
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JH
639 if (pair_to_free)
640 diff_free_filepair(pair_to_free);
427dcb4b 641 }
25d5ea41 642 diff_debug_queue("done copying original", &outq);
427dcb4b 643
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JH
644 free(q->queue);
645 *q = outq;
646 diff_debug_queue("done collapsing", q);
427dcb4b 647
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LT
648 for (i = 0; i < rename_dst_nr; i++)
649 free_filespec(rename_dst[i].two);
5098bafb 650
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JH
651 free(rename_dst);
652 rename_dst = NULL;
653 rename_dst_nr = rename_dst_alloc = 0;
654 free(rename_src);
655 rename_src = NULL;
656 rename_src_nr = rename_src_alloc = 0;
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JH
657 return;
658}