| /* |
| * |
| * Copyright (C) 2005 Junio C Hamano |
| */ |
| #include "cache.h" |
| #include "diff.h" |
| #include "diffcore.h" |
| #include "object-store.h" |
| #include "hashmap.h" |
| #include "progress.h" |
| #include "promisor-remote.h" |
| #include "strmap.h" |
| |
| /* Table of rename/copy destinations */ |
| |
| static struct diff_rename_dst { |
| struct diff_filepair *p; |
| struct diff_filespec *filespec_to_free; |
| int is_rename; /* false -> just a create; true -> rename or copy */ |
| } *rename_dst; |
| static int rename_dst_nr, rename_dst_alloc; |
| /* Mapping from break source pathname to break destination index */ |
| static struct strintmap *break_idx = NULL; |
| |
| static struct diff_rename_dst *locate_rename_dst(struct diff_filepair *p) |
| { |
| /* Lookup by p->ONE->path */ |
| int idx = break_idx ? strintmap_get(break_idx, p->one->path) : -1; |
| return (idx == -1) ? NULL : &rename_dst[idx]; |
| } |
| |
| /* |
| * Returns 0 on success, -1 if we found a duplicate. |
| */ |
| static int add_rename_dst(struct diff_filepair *p) |
| { |
| ALLOC_GROW(rename_dst, rename_dst_nr + 1, rename_dst_alloc); |
| rename_dst[rename_dst_nr].p = p; |
| rename_dst[rename_dst_nr].filespec_to_free = NULL; |
| rename_dst[rename_dst_nr].is_rename = 0; |
| rename_dst_nr++; |
| return 0; |
| } |
| |
| /* Table of rename/copy src files */ |
| static struct diff_rename_src { |
| struct diff_filepair *p; |
| unsigned short score; /* to remember the break score */ |
| } *rename_src; |
| static int rename_src_nr, rename_src_alloc; |
| |
| static void register_rename_src(struct diff_filepair *p) |
| { |
| if (p->broken_pair) { |
| if (!break_idx) { |
| break_idx = xmalloc(sizeof(*break_idx)); |
| strintmap_init(break_idx, -1); |
| } |
| strintmap_set(break_idx, p->one->path, rename_dst_nr); |
| } |
| |
| ALLOC_GROW(rename_src, rename_src_nr + 1, rename_src_alloc); |
| rename_src[rename_src_nr].p = p; |
| rename_src[rename_src_nr].score = p->score; |
| rename_src_nr++; |
| } |
| |
| static int basename_same(struct diff_filespec *src, struct diff_filespec *dst) |
| { |
| int src_len = strlen(src->path), dst_len = strlen(dst->path); |
| while (src_len && dst_len) { |
| char c1 = src->path[--src_len]; |
| char c2 = dst->path[--dst_len]; |
| if (c1 != c2) |
| return 0; |
| if (c1 == '/') |
| return 1; |
| } |
| return (!src_len || src->path[src_len - 1] == '/') && |
| (!dst_len || dst->path[dst_len - 1] == '/'); |
| } |
| |
| struct diff_score { |
| int src; /* index in rename_src */ |
| int dst; /* index in rename_dst */ |
| unsigned short score; |
| short name_score; |
| }; |
| |
| struct prefetch_options { |
| struct repository *repo; |
| int skip_unmodified; |
| }; |
| static void prefetch(void *prefetch_options) |
| { |
| struct prefetch_options *options = prefetch_options; |
| int i; |
| struct oid_array to_fetch = OID_ARRAY_INIT; |
| |
| for (i = 0; i < rename_dst_nr; i++) { |
| if (rename_dst[i].p->renamed_pair) |
| /* |
| * The loop in diffcore_rename() will not need these |
| * blobs, so skip prefetching. |
| */ |
| continue; /* already found exact match */ |
| diff_add_if_missing(options->repo, &to_fetch, |
| rename_dst[i].p->two); |
| } |
| for (i = 0; i < rename_src_nr; i++) { |
| if (options->skip_unmodified && |
| diff_unmodified_pair(rename_src[i].p)) |
| /* |
| * The loop in diffcore_rename() will not need these |
| * blobs, so skip prefetching. |
| */ |
| continue; |
| diff_add_if_missing(options->repo, &to_fetch, |
| rename_src[i].p->one); |
| } |
| promisor_remote_get_direct(options->repo, to_fetch.oid, to_fetch.nr); |
| oid_array_clear(&to_fetch); |
| } |
| |
| static int estimate_similarity(struct repository *r, |
| struct diff_filespec *src, |
| struct diff_filespec *dst, |
| int minimum_score, |
| int skip_unmodified) |
| { |
| /* src points at a file that existed in the original tree (or |
| * optionally a file in the destination tree) and dst points |
| * at a newly created file. They may be quite similar, in which |
| * case we want to say src is renamed to dst or src is copied into |
| * dst, and then some edit has been applied to dst. |
| * |
| * Compare them and return how similar they are, representing |
| * the score as an integer between 0 and MAX_SCORE. |
| * |
| * When there is an exact match, it is considered a better |
| * match than anything else; the destination does not even |
| * call into this function in that case. |
| */ |
| unsigned long max_size, delta_size, base_size, src_copied, literal_added; |
| int score; |
| struct diff_populate_filespec_options dpf_options = { |
| .check_size_only = 1 |
| }; |
| struct prefetch_options prefetch_options = {r, skip_unmodified}; |
| |
| if (r == the_repository && has_promisor_remote()) { |
| dpf_options.missing_object_cb = prefetch; |
| dpf_options.missing_object_data = &prefetch_options; |
| } |
| |
| /* We deal only with regular files. Symlink renames are handled |
| * only when they are exact matches --- in other words, no edits |
| * after renaming. |
| */ |
| if (!S_ISREG(src->mode) || !S_ISREG(dst->mode)) |
| return 0; |
| |
| /* |
| * Need to check that source and destination sizes are |
| * filled in before comparing them. |
| * |
| * If we already have "cnt_data" filled in, we know it's |
| * all good (avoid checking the size for zero, as that |
| * is a possible size - we really should have a flag to |
| * say whether the size is valid or not!) |
| */ |
| if (!src->cnt_data && |
| diff_populate_filespec(r, src, &dpf_options)) |
| return 0; |
| if (!dst->cnt_data && |
| diff_populate_filespec(r, dst, &dpf_options)) |
| return 0; |
| |
| max_size = ((src->size > dst->size) ? src->size : dst->size); |
| base_size = ((src->size < dst->size) ? src->size : dst->size); |
| delta_size = max_size - base_size; |
| |
| /* We would not consider edits that change the file size so |
| * drastically. delta_size must be smaller than |
| * (MAX_SCORE-minimum_score)/MAX_SCORE * min(src->size, dst->size). |
| * |
| * Note that base_size == 0 case is handled here already |
| * and the final score computation below would not have a |
| * divide-by-zero issue. |
| */ |
| if (max_size * (MAX_SCORE-minimum_score) < delta_size * MAX_SCORE) |
| return 0; |
| |
| dpf_options.check_size_only = 0; |
| |
| if (!src->cnt_data && diff_populate_filespec(r, src, &dpf_options)) |
| return 0; |
| if (!dst->cnt_data && diff_populate_filespec(r, dst, &dpf_options)) |
| return 0; |
| |
| if (diffcore_count_changes(r, src, dst, |
| &src->cnt_data, &dst->cnt_data, |
| &src_copied, &literal_added)) |
| return 0; |
| |
| /* How similar are they? |
| * what percentage of material in dst are from source? |
| */ |
| if (!dst->size) |
| score = 0; /* should not happen */ |
| else |
| score = (int)(src_copied * MAX_SCORE / max_size); |
| return score; |
| } |
| |
| static void record_rename_pair(int dst_index, int src_index, int score) |
| { |
| struct diff_filepair *src = rename_src[src_index].p; |
| struct diff_filepair *dst = rename_dst[dst_index].p; |
| |
| if (dst->renamed_pair) |
| die("internal error: dst already matched."); |
| |
| src->one->rename_used++; |
| src->one->count++; |
| |
| rename_dst[dst_index].filespec_to_free = dst->one; |
| rename_dst[dst_index].is_rename = 1; |
| |
| dst->one = src->one; |
| dst->renamed_pair = 1; |
| if (!strcmp(dst->one->path, dst->two->path)) |
| dst->score = rename_src[src_index].score; |
| else |
| dst->score = score; |
| } |
| |
| /* |
| * We sort the rename similarity matrix with the score, in descending |
| * order (the most similar first). |
| */ |
| static int score_compare(const void *a_, const void *b_) |
| { |
| const struct diff_score *a = a_, *b = b_; |
| |
| /* sink the unused ones to the bottom */ |
| if (a->dst < 0) |
| return (0 <= b->dst); |
| else if (b->dst < 0) |
| return -1; |
| |
| if (a->score == b->score) |
| return b->name_score - a->name_score; |
| |
| return b->score - a->score; |
| } |
| |
| struct file_similarity { |
| struct hashmap_entry entry; |
| int index; |
| struct diff_filespec *filespec; |
| }; |
| |
| static unsigned int hash_filespec(struct repository *r, |
| struct diff_filespec *filespec) |
| { |
| if (!filespec->oid_valid) { |
| if (diff_populate_filespec(r, filespec, NULL)) |
| return 0; |
| hash_object_file(r->hash_algo, filespec->data, filespec->size, |
| "blob", &filespec->oid); |
| } |
| return oidhash(&filespec->oid); |
| } |
| |
| static int find_identical_files(struct hashmap *srcs, |
| int dst_index, |
| struct diff_options *options) |
| { |
| int renames = 0; |
| struct diff_filespec *target = rename_dst[dst_index].p->two; |
| struct file_similarity *p, *best = NULL; |
| int i = 100, best_score = -1; |
| unsigned int hash = hash_filespec(options->repo, target); |
| |
| /* |
| * Find the best source match for specified destination. |
| */ |
| p = hashmap_get_entry_from_hash(srcs, hash, NULL, |
| struct file_similarity, entry); |
| hashmap_for_each_entry_from(srcs, p, entry) { |
| int score; |
| struct diff_filespec *source = p->filespec; |
| |
| /* False hash collision? */ |
| if (!oideq(&source->oid, &target->oid)) |
| continue; |
| /* Non-regular files? If so, the modes must match! */ |
| if (!S_ISREG(source->mode) || !S_ISREG(target->mode)) { |
| if (source->mode != target->mode) |
| continue; |
| } |
| /* Give higher scores to sources that haven't been used already */ |
| score = !source->rename_used; |
| if (source->rename_used && options->detect_rename != DIFF_DETECT_COPY) |
| continue; |
| score += basename_same(source, target); |
| if (score > best_score) { |
| best = p; |
| best_score = score; |
| if (score == 2) |
| break; |
| } |
| |
| /* Too many identical alternatives? Pick one */ |
| if (!--i) |
| break; |
| } |
| if (best) { |
| record_rename_pair(dst_index, best->index, MAX_SCORE); |
| renames++; |
| } |
| return renames; |
| } |
| |
| static void insert_file_table(struct repository *r, |
| struct hashmap *table, int index, |
| struct diff_filespec *filespec) |
| { |
| struct file_similarity *entry = xmalloc(sizeof(*entry)); |
| |
| entry->index = index; |
| entry->filespec = filespec; |
| |
| hashmap_entry_init(&entry->entry, hash_filespec(r, filespec)); |
| hashmap_add(table, &entry->entry); |
| } |
| |
| /* |
| * Find exact renames first. |
| * |
| * The first round matches up the up-to-date entries, |
| * and then during the second round we try to match |
| * cache-dirty entries as well. |
| */ |
| static int find_exact_renames(struct diff_options *options) |
| { |
| int i, renames = 0; |
| struct hashmap file_table; |
| |
| /* Add all sources to the hash table in reverse order, because |
| * later on they will be retrieved in LIFO order. |
| */ |
| hashmap_init(&file_table, NULL, NULL, rename_src_nr); |
| for (i = rename_src_nr-1; i >= 0; i--) |
| insert_file_table(options->repo, |
| &file_table, i, |
| rename_src[i].p->one); |
| |
| /* Walk the destinations and find best source match */ |
| for (i = 0; i < rename_dst_nr; i++) |
| renames += find_identical_files(&file_table, i, options); |
| |
| /* Free the hash data structure and entries */ |
| hashmap_clear_and_free(&file_table, struct file_similarity, entry); |
| |
| return renames; |
| } |
| |
| static const char *get_basename(const char *filename) |
| { |
| /* |
| * gitbasename() has to worry about special drives, multiple |
| * directory separator characters, trailing slashes, NULL or |
| * empty strings, etc. We only work on filenames as stored in |
| * git, and thus get to ignore all those complications. |
| */ |
| const char *base = strrchr(filename, '/'); |
| return base ? base + 1 : filename; |
| } |
| |
| static int find_basename_matches(struct diff_options *options, |
| int minimum_score) |
| { |
| /* |
| * When I checked in early 2020, over 76% of file renames in linux |
| * just moved files to a different directory but kept the same |
| * basename. gcc did that with over 64% of renames, gecko did it |
| * with over 79%, and WebKit did it with over 89%. |
| * |
| * Therefore we can bypass the normal exhaustive NxM matrix |
| * comparison of similarities between all potential rename sources |
| * and destinations by instead using file basename as a hint (i.e. |
| * the portion of the filename after the last '/'), checking for |
| * similarity between files with the same basename, and if we find |
| * a pair that are sufficiently similar, record the rename pair and |
| * exclude those two from the NxM matrix. |
| * |
| * This *might* cause us to find a less than optimal pairing (if |
| * there is another file that we are even more similar to but has a |
| * different basename). Given the huge performance advantage |
| * basename matching provides, and given the frequency with which |
| * people use the same basename in real world projects, that's a |
| * trade-off we are willing to accept when doing just rename |
| * detection. |
| * |
| * If someone wants copy detection that implies they are willing to |
| * spend more cycles to find similarities between files, so it may |
| * be less likely that this heuristic is wanted. If someone is |
| * doing break detection, that means they do not want filename |
| * similarity to imply any form of content similiarity, and thus |
| * this heuristic would definitely be incompatible. |
| */ |
| |
| int i, renames = 0; |
| struct strintmap sources; |
| struct strintmap dests; |
| struct hashmap_iter iter; |
| struct strmap_entry *entry; |
| |
| /* |
| * The prefeteching stuff wants to know if it can skip prefetching |
| * blobs that are unmodified...and will then do a little extra work |
| * to verify that the oids are indeed different before prefetching. |
| * Unmodified blobs are only relevant when doing copy detection; |
| * when limiting to rename detection, diffcore_rename[_extended]() |
| * will never be called with unmodified source paths fed to us, so |
| * the extra work necessary to check if rename_src entries are |
| * unmodified would be a small waste. |
| */ |
| int skip_unmodified = 0; |
| |
| /* |
| * Create maps of basename -> fullname(s) for remaining sources and |
| * dests. |
| */ |
| strintmap_init_with_options(&sources, -1, NULL, 0); |
| strintmap_init_with_options(&dests, -1, NULL, 0); |
| for (i = 0; i < rename_src_nr; ++i) { |
| char *filename = rename_src[i].p->one->path; |
| const char *base; |
| |
| /* exact renames removed in remove_unneeded_paths_from_src() */ |
| assert(!rename_src[i].p->one->rename_used); |
| |
| /* Record index within rename_src (i) if basename is unique */ |
| base = get_basename(filename); |
| if (strintmap_contains(&sources, base)) |
| strintmap_set(&sources, base, -1); |
| else |
| strintmap_set(&sources, base, i); |
| } |
| for (i = 0; i < rename_dst_nr; ++i) { |
| char *filename = rename_dst[i].p->two->path; |
| const char *base; |
| |
| if (rename_dst[i].is_rename) |
| continue; /* involved in exact match already. */ |
| |
| /* Record index within rename_dst (i) if basename is unique */ |
| base = get_basename(filename); |
| if (strintmap_contains(&dests, base)) |
| strintmap_set(&dests, base, -1); |
| else |
| strintmap_set(&dests, base, i); |
| } |
| |
| /* Now look for basename matchups and do similarity estimation */ |
| strintmap_for_each_entry(&sources, &iter, entry) { |
| const char *base = entry->key; |
| intptr_t src_index = (intptr_t)entry->value; |
| intptr_t dst_index; |
| if (src_index == -1) |
| continue; |
| |
| if (0 <= (dst_index = strintmap_get(&dests, base))) { |
| struct diff_filespec *one, *two; |
| int score; |
| |
| /* Estimate the similarity */ |
| one = rename_src[src_index].p->one; |
| two = rename_dst[dst_index].p->two; |
| score = estimate_similarity(options->repo, one, two, |
| minimum_score, skip_unmodified); |
| |
| /* If sufficiently similar, record as rename pair */ |
| if (score < minimum_score) |
| continue; |
| record_rename_pair(dst_index, src_index, score); |
| renames++; |
| |
| /* |
| * Found a rename so don't need text anymore; if we |
| * didn't find a rename, the filespec_blob would get |
| * re-used when doing the matrix of comparisons. |
| */ |
| diff_free_filespec_blob(one); |
| diff_free_filespec_blob(two); |
| } |
| } |
| |
| strintmap_clear(&sources); |
| strintmap_clear(&dests); |
| |
| return renames; |
| } |
| |
| #define NUM_CANDIDATE_PER_DST 4 |
| static void record_if_better(struct diff_score m[], struct diff_score *o) |
| { |
| int i, worst; |
| |
| /* find the worst one */ |
| worst = 0; |
| for (i = 1; i < NUM_CANDIDATE_PER_DST; i++) |
| if (score_compare(&m[i], &m[worst]) > 0) |
| worst = i; |
| |
| /* is it better than the worst one? */ |
| if (score_compare(&m[worst], o) > 0) |
| m[worst] = *o; |
| } |
| |
| /* |
| * Returns: |
| * 0 if we are under the limit; |
| * 1 if we need to disable inexact rename detection; |
| * 2 if we would be under the limit if we were given -C instead of -C -C. |
| */ |
| static int too_many_rename_candidates(int num_destinations, int num_sources, |
| struct diff_options *options) |
| { |
| int rename_limit = options->rename_limit; |
| int i, limited_sources; |
| |
| options->needed_rename_limit = 0; |
| |
| /* |
| * This basically does a test for the rename matrix not |
| * growing larger than a "rename_limit" square matrix, ie: |
| * |
| * num_destinations * num_sources > rename_limit * rename_limit |
| * |
| * We use st_mult() to check overflow conditions; in the |
| * exceptional circumstance that size_t isn't large enough to hold |
| * the multiplication, the system won't be able to allocate enough |
| * memory for the matrix anyway. |
| */ |
| if (rename_limit <= 0) |
| rename_limit = 32767; |
| if (st_mult(num_destinations, num_sources) |
| <= st_mult(rename_limit, rename_limit)) |
| return 0; |
| |
| options->needed_rename_limit = |
| num_sources > num_destinations ? num_sources : num_destinations; |
| |
| /* Are we running under -C -C? */ |
| if (!options->flags.find_copies_harder) |
| return 1; |
| |
| /* Would we bust the limit if we were running under -C? */ |
| for (limited_sources = i = 0; i < num_sources; i++) { |
| if (diff_unmodified_pair(rename_src[i].p)) |
| continue; |
| limited_sources++; |
| } |
| if (st_mult(num_destinations, limited_sources) |
| <= st_mult(rename_limit, rename_limit)) |
| return 2; |
| return 1; |
| } |
| |
| static int find_renames(struct diff_score *mx, int dst_cnt, int minimum_score, int copies) |
| { |
| int count = 0, i; |
| |
| for (i = 0; i < dst_cnt * NUM_CANDIDATE_PER_DST; i++) { |
| struct diff_rename_dst *dst; |
| |
| if ((mx[i].dst < 0) || |
| (mx[i].score < minimum_score)) |
| break; /* there is no more usable pair. */ |
| dst = &rename_dst[mx[i].dst]; |
| if (dst->is_rename) |
| continue; /* already done, either exact or fuzzy. */ |
| if (!copies && rename_src[mx[i].src].p->one->rename_used) |
| continue; |
| record_rename_pair(mx[i].dst, mx[i].src, mx[i].score); |
| count++; |
| } |
| return count; |
| } |
| |
| static void remove_unneeded_paths_from_src(int detecting_copies) |
| { |
| int i, new_num_src; |
| |
| if (detecting_copies) |
| return; /* nothing to remove */ |
| if (break_idx) |
| return; /* culling incompatible with break detection */ |
| |
| /* |
| * Note on reasons why we cull unneeded sources but not destinations: |
| * 1) Pairings are stored in rename_dst (not rename_src), which we |
| * need to keep around. So, we just can't cull rename_dst even |
| * if we wanted to. But doing so wouldn't help because... |
| * |
| * 2) There is a matrix pairwise comparison that follows the |
| * "Performing inexact rename detection" progress message. |
| * Iterating over the destinations is done in the outer loop, |
| * hence we only iterate over each of those once and we can |
| * easily skip the outer loop early if the destination isn't |
| * relevant. That's only one check per destination path to |
| * skip. |
| * |
| * By contrast, the sources are iterated in the inner loop; if |
| * we check whether a source can be skipped, then we'll be |
| * checking it N separate times, once for each destination. |
| * We don't want to have to iterate over known-not-needed |
| * sources N times each, so avoid that by removing the sources |
| * from rename_src here. |
| */ |
| for (i = 0, new_num_src = 0; i < rename_src_nr; i++) { |
| /* |
| * renames are stored in rename_dst, so if a rename has |
| * already been detected using this source, we can just |
| * remove the source knowing rename_dst has its info. |
| */ |
| if (rename_src[i].p->one->rename_used) |
| continue; |
| |
| if (new_num_src < i) |
| memcpy(&rename_src[new_num_src], &rename_src[i], |
| sizeof(struct diff_rename_src)); |
| new_num_src++; |
| } |
| |
| rename_src_nr = new_num_src; |
| } |
| |
| void diffcore_rename(struct diff_options *options) |
| { |
| int detect_rename = options->detect_rename; |
| int minimum_score = options->rename_score; |
| struct diff_queue_struct *q = &diff_queued_diff; |
| struct diff_queue_struct outq; |
| struct diff_score *mx; |
| int i, j, rename_count, skip_unmodified = 0; |
| int num_destinations, dst_cnt; |
| int num_sources, want_copies; |
| struct progress *progress = NULL; |
| |
| trace2_region_enter("diff", "setup", options->repo); |
| want_copies = (detect_rename == DIFF_DETECT_COPY); |
| if (!minimum_score) |
| minimum_score = DEFAULT_RENAME_SCORE; |
| |
| for (i = 0; i < q->nr; i++) { |
| struct diff_filepair *p = q->queue[i]; |
| if (!DIFF_FILE_VALID(p->one)) { |
| if (!DIFF_FILE_VALID(p->two)) |
| continue; /* unmerged */ |
| else if (options->single_follow && |
| strcmp(options->single_follow, p->two->path)) |
| continue; /* not interested */ |
| else if (!options->flags.rename_empty && |
| is_empty_blob_oid(&p->two->oid)) |
| continue; |
| else if (add_rename_dst(p) < 0) { |
| warning("skipping rename detection, detected" |
| " duplicate destination '%s'", |
| p->two->path); |
| goto cleanup; |
| } |
| } |
| else if (!options->flags.rename_empty && |
| is_empty_blob_oid(&p->one->oid)) |
| continue; |
| else if (!DIFF_PAIR_UNMERGED(p) && !DIFF_FILE_VALID(p->two)) { |
| /* |
| * If the source is a broken "delete", and |
| * they did not really want to get broken, |
| * that means the source actually stays. |
| * So we increment the "rename_used" score |
| * by one, to indicate ourselves as a user |
| */ |
| if (p->broken_pair && !p->score) |
| p->one->rename_used++; |
| register_rename_src(p); |
| } |
| else if (want_copies) { |
| /* |
| * Increment the "rename_used" score by |
| * one, to indicate ourselves as a user. |
| */ |
| p->one->rename_used++; |
| register_rename_src(p); |
| } |
| } |
| trace2_region_leave("diff", "setup", options->repo); |
| if (rename_dst_nr == 0 || rename_src_nr == 0) |
| goto cleanup; /* nothing to do */ |
| |
| trace2_region_enter("diff", "exact renames", options->repo); |
| /* |
| * We really want to cull the candidates list early |
| * with cheap tests in order to avoid doing deltas. |
| */ |
| rename_count = find_exact_renames(options); |
| trace2_region_leave("diff", "exact renames", options->repo); |
| |
| /* Did we only want exact renames? */ |
| if (minimum_score == MAX_SCORE) |
| goto cleanup; |
| |
| num_sources = rename_src_nr; |
| |
| if (want_copies || break_idx) { |
| /* |
| * Cull sources: |
| * - remove ones corresponding to exact renames |
| */ |
| trace2_region_enter("diff", "cull after exact", options->repo); |
| remove_unneeded_paths_from_src(want_copies); |
| trace2_region_leave("diff", "cull after exact", options->repo); |
| } else { |
| /* Determine minimum score to match basenames */ |
| double factor = 0.5; |
| char *basename_factor = getenv("GIT_BASENAME_FACTOR"); |
| int min_basename_score; |
| |
| if (basename_factor) |
| factor = strtol(basename_factor, NULL, 10)/100.0; |
| assert(factor >= 0.0 && factor <= 1.0); |
| min_basename_score = minimum_score + |
| (int)(factor * (MAX_SCORE - minimum_score)); |
| |
| /* |
| * Cull sources: |
| * - remove ones involved in renames (found via exact match) |
| */ |
| trace2_region_enter("diff", "cull after exact", options->repo); |
| remove_unneeded_paths_from_src(want_copies); |
| trace2_region_leave("diff", "cull after exact", options->repo); |
| |
| /* Utilize file basenames to quickly find renames. */ |
| trace2_region_enter("diff", "basename matches", options->repo); |
| rename_count += find_basename_matches(options, |
| min_basename_score); |
| trace2_region_leave("diff", "basename matches", options->repo); |
| |
| /* |
| * Cull sources, again: |
| * - remove ones involved in renames (found via basenames) |
| */ |
| trace2_region_enter("diff", "cull basename", options->repo); |
| remove_unneeded_paths_from_src(want_copies); |
| trace2_region_leave("diff", "cull basename", options->repo); |
| } |
| |
| /* Calculate how many rename destinations are left */ |
| num_destinations = (rename_dst_nr - rename_count); |
| num_sources = rename_src_nr; /* rename_src_nr reflects lower number */ |
| |
| /* All done? */ |
| if (!num_destinations || !num_sources) |
| goto cleanup; |
| |
| switch (too_many_rename_candidates(num_destinations, num_sources, |
| options)) { |
| case 1: |
| goto cleanup; |
| case 2: |
| options->degraded_cc_to_c = 1; |
| skip_unmodified = 1; |
| break; |
| default: |
| break; |
| } |
| |
| trace2_region_enter("diff", "inexact renames", options->repo); |
| if (options->show_rename_progress) { |
| progress = start_delayed_progress( |
| _("Performing inexact rename detection"), |
| (uint64_t)num_destinations * (uint64_t)num_sources); |
| } |
| |
| CALLOC_ARRAY(mx, st_mult(NUM_CANDIDATE_PER_DST, num_destinations)); |
| for (dst_cnt = i = 0; i < rename_dst_nr; i++) { |
| struct diff_filespec *two = rename_dst[i].p->two; |
| struct diff_score *m; |
| |
| if (rename_dst[i].is_rename) |
| continue; /* exact or basename match already handled */ |
| |
| m = &mx[dst_cnt * NUM_CANDIDATE_PER_DST]; |
| for (j = 0; j < NUM_CANDIDATE_PER_DST; j++) |
| m[j].dst = -1; |
| |
| for (j = 0; j < rename_src_nr; j++) { |
| struct diff_filespec *one = rename_src[j].p->one; |
| struct diff_score this_src; |
| |
| assert(!one->rename_used || want_copies || break_idx); |
| |
| if (skip_unmodified && |
| diff_unmodified_pair(rename_src[j].p)) |
| continue; |
| |
| this_src.score = estimate_similarity(options->repo, |
| one, two, |
| minimum_score, |
| skip_unmodified); |
| this_src.name_score = basename_same(one, two); |
| this_src.dst = i; |
| this_src.src = j; |
| record_if_better(m, &this_src); |
| /* |
| * Once we run estimate_similarity, |
| * We do not need the text anymore. |
| */ |
| diff_free_filespec_blob(one); |
| diff_free_filespec_blob(two); |
| } |
| dst_cnt++; |
| display_progress(progress, |
| (uint64_t)dst_cnt * (uint64_t)num_sources); |
| } |
| stop_progress(&progress); |
| |
| /* cost matrix sorted by most to least similar pair */ |
| STABLE_QSORT(mx, dst_cnt * NUM_CANDIDATE_PER_DST, score_compare); |
| |
| rename_count += find_renames(mx, dst_cnt, minimum_score, 0); |
| if (want_copies) |
| rename_count += find_renames(mx, dst_cnt, minimum_score, 1); |
| free(mx); |
| trace2_region_leave("diff", "inexact renames", options->repo); |
| |
| cleanup: |
| /* At this point, we have found some renames and copies and they |
| * are recorded in rename_dst. The original list is still in *q. |
| */ |
| trace2_region_enter("diff", "write back to queue", options->repo); |
| DIFF_QUEUE_CLEAR(&outq); |
| for (i = 0; i < q->nr; i++) { |
| struct diff_filepair *p = q->queue[i]; |
| struct diff_filepair *pair_to_free = NULL; |
| |
| if (DIFF_PAIR_UNMERGED(p)) { |
| diff_q(&outq, p); |
| } |
| else if (!DIFF_FILE_VALID(p->one) && DIFF_FILE_VALID(p->two)) { |
| /* Creation */ |
| diff_q(&outq, p); |
| } |
| else if (DIFF_FILE_VALID(p->one) && !DIFF_FILE_VALID(p->two)) { |
| /* |
| * Deletion |
| * |
| * We would output this delete record if: |
| * |
| * (1) this is a broken delete and the counterpart |
| * broken create remains in the output; or |
| * (2) this is not a broken delete, and rename_dst |
| * does not have a rename/copy to move p->one->path |
| * out of existence. |
| * |
| * Otherwise, the counterpart broken create |
| * has been turned into a rename-edit; or |
| * delete did not have a matching create to |
| * begin with. |
| */ |
| if (DIFF_PAIR_BROKEN(p)) { |
| /* broken delete */ |
| struct diff_rename_dst *dst = locate_rename_dst(p); |
| if (!dst) |
| BUG("tracking failed somehow; failed to find associated dst for broken pair"); |
| if (dst->is_rename) |
| /* counterpart is now rename/copy */ |
| pair_to_free = p; |
| } |
| else { |
| if (p->one->rename_used) |
| /* this path remains */ |
| pair_to_free = p; |
| } |
| |
| if (!pair_to_free) |
| diff_q(&outq, p); |
| } |
| else if (!diff_unmodified_pair(p)) |
| /* all the usual ones need to be kept */ |
| diff_q(&outq, p); |
| else |
| /* no need to keep unmodified pairs; FIXME: remove earlier? */ |
| pair_to_free = p; |
| |
| if (pair_to_free) |
| diff_free_filepair(pair_to_free); |
| } |
| diff_debug_queue("done copying original", &outq); |
| |
| free(q->queue); |
| *q = outq; |
| diff_debug_queue("done collapsing", q); |
| |
| for (i = 0; i < rename_dst_nr; i++) |
| if (rename_dst[i].filespec_to_free) |
| free_filespec(rename_dst[i].filespec_to_free); |
| |
| FREE_AND_NULL(rename_dst); |
| rename_dst_nr = rename_dst_alloc = 0; |
| FREE_AND_NULL(rename_src); |
| rename_src_nr = rename_src_alloc = 0; |
| if (break_idx) { |
| strintmap_clear(break_idx); |
| FREE_AND_NULL(break_idx); |
| } |
| trace2_region_leave("diff", "write back to queue", options->repo); |
| return; |
| } |