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Copy pathdiff_tform.c
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948 lines (747 loc) · 25 KB
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/*
* Copyright (C) the libgit2 contributors. All rights reserved.
*
* This file is part of libgit2, distributed under the GNU GPL v2 with
* a Linking Exception. For full terms see the included COPYING file.
*/
#include "common.h"
#include "git2/config.h"
#include "git2/blob.h"
#include "diff.h"
#include "hashsig.h"
#include "path.h"
#include "fileops.h"
static git_diff_delta *diff_delta__dup(
const git_diff_delta *d, git_pool *pool)
{
git_diff_delta *delta = git__malloc(sizeof(git_diff_delta));
if (!delta)
return NULL;
memcpy(delta, d, sizeof(git_diff_delta));
GIT_DIFF_FLAG__CLEAR_INTERNAL(delta->flags);
if (d->old_file.path != NULL) {
delta->old_file.path = git_pool_strdup(pool, d->old_file.path);
if (delta->old_file.path == NULL)
goto fail;
}
if (d->new_file.path != d->old_file.path && d->new_file.path != NULL) {
delta->new_file.path = git_pool_strdup(pool, d->new_file.path);
if (delta->new_file.path == NULL)
goto fail;
} else {
delta->new_file.path = delta->old_file.path;
}
return delta;
fail:
git__free(delta);
return NULL;
}
static git_diff_delta *diff_delta__merge_like_cgit(
const git_diff_delta *a, const git_diff_delta *b, git_pool *pool)
{
git_diff_delta *dup;
/* Emulate C git for merging two diffs (a la 'git diff <sha>').
*
* When C git does a diff between the work dir and a tree, it actually
* diffs with the index but uses the workdir contents. This emulates
* those choices so we can emulate the type of diff.
*
* We have three file descriptions here, let's call them:
* f1 = a->old_file
* f2 = a->new_file AND b->old_file
* f3 = b->new_file
*/
/* if f2 == f3 or f2 is deleted, then just dup the 'a' diff */
if (b->status == GIT_DELTA_UNMODIFIED || a->status == GIT_DELTA_DELETED)
return diff_delta__dup(a, pool);
/* otherwise, base this diff on the 'b' diff */
if ((dup = diff_delta__dup(b, pool)) == NULL)
return NULL;
/* If 'a' status is uninteresting, then we're done */
if (a->status == GIT_DELTA_UNMODIFIED)
return dup;
assert(a->status != GIT_DELTA_UNMODIFIED);
assert(b->status != GIT_DELTA_UNMODIFIED);
/* A cgit exception is that the diff of a file that is only in the
* index (i.e. not in HEAD nor workdir) is given as empty.
*/
if (dup->status == GIT_DELTA_DELETED) {
if (a->status == GIT_DELTA_ADDED)
dup->status = GIT_DELTA_UNMODIFIED;
/* else don't overwrite DELETE status */
} else {
dup->status = a->status;
}
git_oid_cpy(&dup->old_file.oid, &a->old_file.oid);
dup->old_file.mode = a->old_file.mode;
dup->old_file.size = a->old_file.size;
dup->old_file.flags = a->old_file.flags;
return dup;
}
int git_diff_merge(
git_diff_list *onto,
const git_diff_list *from)
{
int error = 0;
git_pool onto_pool;
git_vector onto_new;
git_diff_delta *delta;
bool ignore_case = false;
unsigned int i, j;
assert(onto && from);
if (!from->deltas.length)
return 0;
if (git_vector_init(
&onto_new, onto->deltas.length, git_diff_delta__cmp) < 0 ||
git_pool_init(&onto_pool, 1, 0) < 0)
return -1;
if ((onto->opts.flags & GIT_DIFF_DELTAS_ARE_ICASE) != 0 ||
(from->opts.flags & GIT_DIFF_DELTAS_ARE_ICASE) != 0)
{
ignore_case = true;
/* This function currently only supports merging diff lists that
* are sorted identically. */
assert((onto->opts.flags & GIT_DIFF_DELTAS_ARE_ICASE) != 0 &&
(from->opts.flags & GIT_DIFF_DELTAS_ARE_ICASE) != 0);
}
for (i = 0, j = 0; i < onto->deltas.length || j < from->deltas.length; ) {
git_diff_delta *o = GIT_VECTOR_GET(&onto->deltas, i);
const git_diff_delta *f = GIT_VECTOR_GET(&from->deltas, j);
int cmp = !f ? -1 : !o ? 1 : STRCMP_CASESELECT(ignore_case, o->old_file.path, f->old_file.path);
if (cmp < 0) {
delta = diff_delta__dup(o, &onto_pool);
i++;
} else if (cmp > 0) {
delta = diff_delta__dup(f, &onto_pool);
j++;
} else {
delta = diff_delta__merge_like_cgit(o, f, &onto_pool);
i++;
j++;
}
/* the ignore rules for the target may not match the source
* or the result of a merged delta could be skippable...
*/
if (git_diff_delta__should_skip(&onto->opts, delta)) {
git__free(delta);
continue;
}
if ((error = !delta ? -1 : git_vector_insert(&onto_new, delta)) < 0)
break;
}
if (!error) {
git_vector_swap(&onto->deltas, &onto_new);
git_pool_swap(&onto->pool, &onto_pool);
onto->new_src = from->new_src;
/* prefix strings also come from old pool, so recreate those.*/
onto->opts.old_prefix =
git_pool_strdup_safe(&onto->pool, onto->opts.old_prefix);
onto->opts.new_prefix =
git_pool_strdup_safe(&onto->pool, onto->opts.new_prefix);
}
git_vector_foreach(&onto_new, i, delta)
git__free(delta);
git_vector_free(&onto_new);
git_pool_clear(&onto_pool);
return error;
}
int git_diff_find_similar__hashsig_for_file(
void **out, const git_diff_file *f, const char *path, void *p)
{
git_hashsig_option_t opt = (git_hashsig_option_t)p;
int error = 0;
GIT_UNUSED(f);
error = git_hashsig_create_fromfile((git_hashsig **)out, path, opt);
if (error == GIT_EBUFS) {
error = 0;
giterr_clear();
}
return error;
}
int git_diff_find_similar__hashsig_for_buf(
void **out, const git_diff_file *f, const char *buf, size_t len, void *p)
{
git_hashsig_option_t opt = (git_hashsig_option_t)p;
int error = 0;
GIT_UNUSED(f);
error = git_hashsig_create((git_hashsig **)out, buf, len, opt);
if (error == GIT_EBUFS) {
error = 0;
giterr_clear();
}
return error;
}
void git_diff_find_similar__hashsig_free(void *sig, void *payload)
{
GIT_UNUSED(payload);
git_hashsig_free(sig);
}
int git_diff_find_similar__calc_similarity(
int *score, void *siga, void *sigb, void *payload)
{
GIT_UNUSED(payload);
*score = git_hashsig_compare(siga, sigb);
return 0;
}
#define DEFAULT_THRESHOLD 50
#define DEFAULT_BREAK_REWRITE_THRESHOLD 60
#define DEFAULT_RENAME_LIMIT 200
static int normalize_find_opts(
git_diff_list *diff,
git_diff_find_options *opts,
git_diff_find_options *given)
{
git_config *cfg = NULL;
if (diff->repo != NULL &&
git_repository_config__weakptr(&cfg, diff->repo) < 0)
return -1;
if (given != NULL)
memcpy(opts, given, sizeof(*opts));
else {
const char *val = NULL;
GIT_INIT_STRUCTURE(opts, GIT_DIFF_FIND_OPTIONS_VERSION);
opts->flags = GIT_DIFF_FIND_RENAMES;
if (git_config_get_string(&val, cfg, "diff.renames") < 0)
giterr_clear();
else if (val &&
(!strcasecmp(val, "copies") || !strcasecmp(val, "copy")))
opts->flags = GIT_DIFF_FIND_RENAMES | GIT_DIFF_FIND_COPIES;
}
GITERR_CHECK_VERSION(opts, GIT_DIFF_FIND_OPTIONS_VERSION, "git_diff_find_options");
/* some flags imply others */
if (opts->flags & GIT_DIFF_FIND_EXACT_MATCH_ONLY) {
/* if we are only looking for exact matches, then don't turn
* MODIFIED items into ADD/DELETE pairs because it's too picky
*/
opts->flags &= ~(GIT_DIFF_FIND_REWRITES | GIT_DIFF_BREAK_REWRITES);
/* similarly, don't look for self-rewrites to split */
opts->flags &= ~GIT_DIFF_FIND_RENAMES_FROM_REWRITES;
}
if (opts->flags & GIT_DIFF_FIND_RENAMES_FROM_REWRITES)
opts->flags |= GIT_DIFF_FIND_RENAMES;
if (opts->flags & GIT_DIFF_FIND_COPIES_FROM_UNMODIFIED)
opts->flags |= GIT_DIFF_FIND_COPIES;
if (opts->flags & GIT_DIFF_BREAK_REWRITES)
opts->flags |= GIT_DIFF_FIND_REWRITES;
#define USE_DEFAULT(X) ((X) == 0 || (X) > 100)
if (USE_DEFAULT(opts->rename_threshold))
opts->rename_threshold = DEFAULT_THRESHOLD;
if (USE_DEFAULT(opts->rename_from_rewrite_threshold))
opts->rename_from_rewrite_threshold = DEFAULT_THRESHOLD;
if (USE_DEFAULT(opts->copy_threshold))
opts->copy_threshold = DEFAULT_THRESHOLD;
if (USE_DEFAULT(opts->break_rewrite_threshold))
opts->break_rewrite_threshold = DEFAULT_BREAK_REWRITE_THRESHOLD;
#undef USE_DEFAULT
if (!opts->rename_limit) {
int32_t limit = 0;
opts->rename_limit = DEFAULT_RENAME_LIMIT;
if (git_config_get_int32(&limit, cfg, "diff.renameLimit") < 0)
giterr_clear();
else if (limit > 0)
opts->rename_limit = limit;
}
/* assign the internal metric with whitespace flag as payload */
if (!opts->metric) {
opts->metric = git__malloc(sizeof(git_diff_similarity_metric));
GITERR_CHECK_ALLOC(opts->metric);
opts->metric->file_signature = git_diff_find_similar__hashsig_for_file;
opts->metric->buffer_signature = git_diff_find_similar__hashsig_for_buf;
opts->metric->free_signature = git_diff_find_similar__hashsig_free;
opts->metric->similarity = git_diff_find_similar__calc_similarity;
if (opts->flags & GIT_DIFF_FIND_IGNORE_WHITESPACE)
opts->metric->payload = (void *)GIT_HASHSIG_IGNORE_WHITESPACE;
else if (opts->flags & GIT_DIFF_FIND_DONT_IGNORE_WHITESPACE)
opts->metric->payload = (void *)GIT_HASHSIG_NORMAL;
else
opts->metric->payload = (void *)GIT_HASHSIG_SMART_WHITESPACE;
}
return 0;
}
static int apply_splits_and_deletes(
git_diff_list *diff, size_t expected_size, bool actually_split)
{
git_vector onto = GIT_VECTOR_INIT;
size_t i;
git_diff_delta *delta, *deleted;
if (git_vector_init(&onto, expected_size, git_diff_delta__cmp) < 0)
return -1;
/* build new delta list without TO_DELETE and splitting TO_SPLIT */
git_vector_foreach(&diff->deltas, i, delta) {
if ((delta->flags & GIT_DIFF_FLAG__TO_DELETE) != 0)
continue;
if ((delta->flags & GIT_DIFF_FLAG__TO_SPLIT) != 0 && actually_split) {
delta->similarity = 0;
/* make new record for DELETED side of split */
if (!(deleted = diff_delta__dup(delta, &diff->pool)))
goto on_error;
deleted->status = GIT_DELTA_DELETED;
memset(&deleted->new_file, 0, sizeof(deleted->new_file));
deleted->new_file.path = deleted->old_file.path;
deleted->new_file.flags |= GIT_DIFF_FLAG_VALID_OID;
if (git_vector_insert(&onto, deleted) < 0)
goto on_error;
if (diff->new_src == GIT_ITERATOR_TYPE_WORKDIR)
delta->status = GIT_DELTA_UNTRACKED;
else
delta->status = GIT_DELTA_ADDED;
memset(&delta->old_file, 0, sizeof(delta->old_file));
delta->old_file.path = delta->new_file.path;
delta->old_file.flags |= GIT_DIFF_FLAG_VALID_OID;
}
/* clean up delta before inserting into new list */
GIT_DIFF_FLAG__CLEAR_INTERNAL(delta->flags);
if (delta->status != GIT_DELTA_COPIED &&
delta->status != GIT_DELTA_RENAMED &&
(delta->status != GIT_DELTA_MODIFIED || actually_split))
delta->similarity = 0;
/* insert into new list */
if (git_vector_insert(&onto, delta) < 0)
goto on_error;
}
/* cannot return an error past this point */
/* free deltas from old list that didn't make it to the new one */
git_vector_foreach(&diff->deltas, i, delta) {
if ((delta->flags & GIT_DIFF_FLAG__TO_DELETE) != 0)
git__free(delta);
}
/* swap new delta list into place */
git_vector_swap(&diff->deltas, &onto);
git_vector_free(&onto);
git_vector_sort(&diff->deltas);
return 0;
on_error:
git_vector_foreach(&onto, i, delta)
git__free(delta);
git_vector_free(&onto);
return -1;
}
GIT_INLINE(git_diff_file *) similarity_get_file(git_diff_list *diff, size_t idx)
{
git_diff_delta *delta = git_vector_get(&diff->deltas, idx / 2);
return (idx & 1) ? &delta->new_file : &delta->old_file;
}
static int similarity_calc(
git_diff_list *diff,
const git_diff_find_options *opts,
size_t file_idx,
void **cache)
{
int error = 0;
git_diff_file *file = similarity_get_file(diff, file_idx);
git_iterator_type_t src = (file_idx & 1) ? diff->new_src : diff->old_src;
if (src == GIT_ITERATOR_TYPE_WORKDIR) { /* compute hashsig from file */
git_buf path = GIT_BUF_INIT;
/* TODO: apply wd-to-odb filters to file data if necessary */
if ((error = git_buf_joinpath(
&path, git_repository_workdir(diff->repo), file->path)) < 0)
return error;
/* if path is not a regular file, just skip this item */
if (git_path_isfile(path.ptr))
error = opts->metric->file_signature(
&cache[file_idx], file, path.ptr, opts->metric->payload);
git_buf_free(&path);
} else { /* compute hashsig from blob buffer */
git_blob *blob = NULL;
git_off_t blobsize;
/* TODO: add max size threshold a la diff? */
if (git_blob_lookup(&blob, diff->repo, &file->oid) < 0) {
/* if lookup fails, just skip this item in similarity calc */
giterr_clear();
return 0;
}
blobsize = git_blob_rawsize(blob);
if (!git__is_sizet(blobsize)) /* ? what to do ? */
blobsize = (size_t)-1;
error = opts->metric->buffer_signature(
&cache[file_idx], file, git_blob_rawcontent(blob),
(size_t)blobsize, opts->metric->payload);
git_blob_free(blob);
}
return error;
}
#define FLAG_SET(opts,flag_name) (((opts)->flags & flag_name) != 0)
/* - score < 0 means files cannot be compared
* - score >= 100 means files are exact match
* - score == 0 means files are completely different
*/
static int similarity_measure(
int *score,
git_diff_list *diff,
const git_diff_find_options *opts,
void **cache,
size_t a_idx,
size_t b_idx)
{
git_diff_file *a_file = similarity_get_file(diff, a_idx);
git_diff_file *b_file = similarity_get_file(diff, b_idx);
bool exact_match = FLAG_SET(opts, GIT_DIFF_FIND_EXACT_MATCH_ONLY);
*score = -1;
/* don't try to compare files of different types */
if (GIT_MODE_TYPE(a_file->mode) != GIT_MODE_TYPE(b_file->mode))
return 0;
/* if exact match is requested, force calculation of missing OIDs now */
if (exact_match) {
if (git_oid_iszero(&a_file->oid) &&
diff->old_src == GIT_ITERATOR_TYPE_WORKDIR &&
!git_diff__oid_for_file(diff->repo, a_file->path,
a_file->mode, a_file->size, &a_file->oid))
a_file->flags |= GIT_DIFF_FLAG_VALID_OID;
if (git_oid_iszero(&b_file->oid) &&
diff->new_src == GIT_ITERATOR_TYPE_WORKDIR &&
!git_diff__oid_for_file(diff->repo, b_file->path,
b_file->mode, b_file->size, &b_file->oid))
b_file->flags |= GIT_DIFF_FLAG_VALID_OID;
}
/* check OID match as a quick test */
if (git_oid__cmp(&a_file->oid, &b_file->oid) == 0) {
*score = 100;
return 0;
}
/* don't calculate signatures if we are doing exact match */
if (exact_match) {
*score = 0;
return 0;
}
/* update signature cache if needed */
if (!cache[a_idx] && similarity_calc(diff, opts, a_idx, cache) < 0)
return -1;
if (!cache[b_idx] && similarity_calc(diff, opts, b_idx, cache) < 0)
return -1;
/* some metrics may not wish to process this file (too big / too small) */
if (!cache[a_idx] || !cache[b_idx])
return 0;
/* compare signatures */
return opts->metric->similarity(
score, cache[a_idx], cache[b_idx], opts->metric->payload);
}
static int calc_self_similarity(
git_diff_list *diff,
const git_diff_find_options *opts,
size_t delta_idx,
void **cache)
{
int error, similarity = -1;
git_diff_delta *delta = GIT_VECTOR_GET(&diff->deltas, delta_idx);
if ((delta->flags & GIT_DIFF_FLAG__HAS_SELF_SIMILARITY) != 0)
return 0;
error = similarity_measure(
&similarity, diff, opts, cache, 2 * delta_idx, 2 * delta_idx + 1);
if (error < 0)
return error;
if (similarity >= 0) {
delta->similarity = (uint32_t)similarity;
delta->flags |= GIT_DIFF_FLAG__HAS_SELF_SIMILARITY;
}
return 0;
}
static bool is_rename_target(
git_diff_list *diff,
const git_diff_find_options *opts,
size_t delta_idx,
void **cache)
{
git_diff_delta *delta = GIT_VECTOR_GET(&diff->deltas, delta_idx);
/* skip things that aren't plain blobs */
if (!GIT_MODE_ISBLOB(delta->new_file.mode))
return false;
/* only consider ADDED, RENAMED, COPIED, and split MODIFIED as
* targets; maybe include UNTRACKED and IGNORED if requested.
*/
switch (delta->status) {
case GIT_DELTA_UNMODIFIED:
case GIT_DELTA_DELETED:
return false;
case GIT_DELTA_MODIFIED:
if (!FLAG_SET(opts, GIT_DIFF_FIND_REWRITES) &&
!FLAG_SET(opts, GIT_DIFF_FIND_RENAMES_FROM_REWRITES))
return false;
if (calc_self_similarity(diff, opts, delta_idx, cache) < 0)
return false;
if (FLAG_SET(opts, GIT_DIFF_BREAK_REWRITES) &&
delta->similarity < opts->break_rewrite_threshold) {
delta->flags |= GIT_DIFF_FLAG__TO_SPLIT;
break;
}
if (FLAG_SET(opts, GIT_DIFF_FIND_RENAMES_FROM_REWRITES) &&
delta->similarity < opts->rename_from_rewrite_threshold)
break;
return false;
case GIT_DELTA_UNTRACKED:
case GIT_DELTA_IGNORED:
if (!FLAG_SET(opts, GIT_DIFF_FIND_FOR_UNTRACKED))
return false;
break;
default: /* all other status values should be checked */
break;
}
delta->flags |= GIT_DIFF_FLAG__IS_RENAME_TARGET;
return true;
}
static bool is_rename_source(
git_diff_list *diff,
const git_diff_find_options *opts,
size_t delta_idx,
void **cache)
{
git_diff_delta *delta = GIT_VECTOR_GET(&diff->deltas, delta_idx);
/* skip things that aren't blobs */
if (!GIT_MODE_ISBLOB(delta->old_file.mode))
return false;
switch (delta->status) {
case GIT_DELTA_ADDED:
case GIT_DELTA_UNTRACKED:
case GIT_DELTA_IGNORED:
return false;
case GIT_DELTA_DELETED:
case GIT_DELTA_TYPECHANGE:
break;
case GIT_DELTA_UNMODIFIED:
if (!FLAG_SET(opts, GIT_DIFF_FIND_COPIES_FROM_UNMODIFIED))
return false;
break;
default: /* MODIFIED, RENAMED, COPIED */
/* if we're finding copies, this could be a source */
if (FLAG_SET(opts, GIT_DIFF_FIND_COPIES))
break;
/* otherwise, this is only a source if we can split it */
if (!FLAG_SET(opts, GIT_DIFF_FIND_REWRITES) &&
!FLAG_SET(opts, GIT_DIFF_FIND_RENAMES_FROM_REWRITES))
return false;
if (calc_self_similarity(diff, opts, delta_idx, cache) < 0)
return false;
if (FLAG_SET(opts, GIT_DIFF_BREAK_REWRITES) &&
delta->similarity < opts->break_rewrite_threshold) {
delta->flags |= GIT_DIFF_FLAG__TO_SPLIT;
break;
}
if (FLAG_SET(opts, GIT_DIFF_FIND_RENAMES_FROM_REWRITES) &&
delta->similarity < opts->rename_from_rewrite_threshold)
break;
return false;
}
delta->flags |= GIT_DIFF_FLAG__IS_RENAME_SOURCE;
return true;
}
GIT_INLINE(bool) delta_is_split(git_diff_delta *delta)
{
return (delta->status == GIT_DELTA_TYPECHANGE ||
(delta->flags & GIT_DIFF_FLAG__TO_SPLIT) != 0);
}
GIT_INLINE(bool) delta_is_new_only(git_diff_delta *delta)
{
return (delta->status == GIT_DELTA_ADDED ||
delta->status == GIT_DELTA_UNTRACKED ||
delta->status == GIT_DELTA_IGNORED);
}
GIT_INLINE(void) delta_make_rename(
git_diff_delta *to, const git_diff_delta *from, uint32_t similarity)
{
to->status = GIT_DELTA_RENAMED;
to->similarity = similarity;
memcpy(&to->old_file, &from->old_file, sizeof(to->old_file));
to->flags &= ~GIT_DIFF_FLAG__TO_SPLIT;
}
typedef struct {
uint32_t idx;
uint32_t similarity;
} diff_find_match;
int git_diff_find_similar(
git_diff_list *diff,
git_diff_find_options *given_opts)
{
size_t i, j, sigcache_size;
int error = 0, similarity;
git_diff_delta *from, *to;
git_diff_find_options opts;
size_t num_srcs = 0, num_tgts = 0, tried_srcs = 0, tried_tgts = 0;
size_t num_rewrites = 0, num_updates = 0, num_bumped = 0;
void **sigcache; /* cache of similarity metric file signatures */
diff_find_match *match_srcs = NULL, *match_tgts = NULL, *best_match;
git_diff_file swap;
if ((error = normalize_find_opts(diff, &opts, given_opts)) < 0)
return error;
/* TODO: maybe abort if deltas.length > rename_limit ??? */
if (!git__is_uint32(diff->deltas.length))
return 0;
sigcache_size = diff->deltas.length * 2; /* keep size b/c diff may change */
sigcache = git__calloc(sigcache_size, sizeof(void *));
GITERR_CHECK_ALLOC(sigcache);
/* Label rename sources and targets
*
* This will also set self-similarity scores for MODIFIED files and
* mark them for splitting if break-rewrites is enabled
*/
git_vector_foreach(&diff->deltas, i, to) {
if (is_rename_source(diff, &opts, i, sigcache))
++num_srcs;
if (is_rename_target(diff, &opts, i, sigcache))
++num_tgts;
}
/* if there are no candidate srcs or tgts, we're done */
if (!num_srcs || !num_tgts)
goto cleanup;
match_tgts = git__calloc(diff->deltas.length, sizeof(diff_find_match));
GITERR_CHECK_ALLOC(match_tgts);
match_srcs = git__calloc(diff->deltas.length, sizeof(diff_find_match));
GITERR_CHECK_ALLOC(match_srcs);
/*
* Find best-fit matches for rename / copy candidates
*/
find_best_matches:
tried_tgts = num_bumped = 0;
git_vector_foreach(&diff->deltas, i, to) {
/* skip things that are not rename targets */
if ((to->flags & GIT_DIFF_FLAG__IS_RENAME_TARGET) == 0)
continue;
tried_srcs = 0;
git_vector_foreach(&diff->deltas, j, from) {
/* skip things that are not rename sources */
if ((from->flags & GIT_DIFF_FLAG__IS_RENAME_SOURCE) == 0)
continue;
/* calculate similarity for this pair and find best match */
if (i == j)
similarity = -1; /* don't measure self-similarity here */
else if ((error = similarity_measure(
&similarity, diff, &opts, sigcache, 2 * j, 2 * i + 1)) < 0)
goto cleanup;
/* if this pairing is better for the src and the tgt, keep it */
if (similarity > 0 &&
match_tgts[i].similarity < (uint32_t)similarity &&
match_srcs[j].similarity < (uint32_t)similarity)
{
if (match_tgts[i].similarity > 0) {
match_tgts[match_srcs[j].idx].similarity = 0;
match_srcs[match_tgts[i].idx].similarity = 0;
++num_bumped;
}
match_tgts[i].similarity = (uint32_t)similarity;
match_tgts[i].idx = (uint32_t)j;
match_srcs[j].similarity = (uint32_t)similarity;
match_srcs[j].idx = (uint32_t)i;
}
if (++tried_srcs >= num_srcs)
break;
/* cap on maximum targets we'll examine (per "to" file) */
if (tried_srcs > opts.rename_limit)
break;
}
if (++tried_tgts >= num_tgts)
break;
}
if (num_bumped > 0) /* try again if we bumped some items */
goto find_best_matches;
/*
* Rewrite the diffs with renames / copies
*/
tried_tgts = 0;
git_vector_foreach(&diff->deltas, i, to) {
/* skip things that are not rename targets */
if ((to->flags & GIT_DIFF_FLAG__IS_RENAME_TARGET) == 0)
continue;
/* check if this delta was the target of a similarity */
best_match = &match_tgts[i];
if (!best_match->similarity)
continue;
j = best_match->idx;
from = GIT_VECTOR_GET(&diff->deltas, j);
/* possible scenarios:
* 1. from DELETE to ADD/UNTRACK/IGNORE = RENAME
* 2. from DELETE to SPLIT/TYPECHANGE = RENAME + DELETE
* 3. from SPLIT/TYPECHANGE to ADD/UNTRACK/IGNORE = ADD + RENAME
* 4. from SPLIT/TYPECHANGE to SPLIT/TYPECHANGE = RENAME + SPLIT
* 5. from OTHER to ADD/UNTRACK/IGNORE = OTHER + COPY
*/
if (from->status == GIT_DELTA_DELETED) {
if (delta_is_new_only(to)) {
if (best_match->similarity < opts.rename_threshold)
continue;
delta_make_rename(to, from, best_match->similarity);
from->flags |= GIT_DIFF_FLAG__TO_DELETE;
num_rewrites++;
} else {
assert(delta_is_split(to));
if (best_match->similarity < opts.rename_from_rewrite_threshold)
continue;
memcpy(&swap, &to->old_file, sizeof(swap));
delta_make_rename(to, from, best_match->similarity);
num_rewrites--;
from->status = GIT_DELTA_DELETED;
memcpy(&from->old_file, &swap, sizeof(from->old_file));
memset(&from->new_file, 0, sizeof(from->new_file));
from->new_file.path = from->old_file.path;
from->new_file.flags |= GIT_DIFF_FLAG_VALID_OID;
num_updates++;
}
}
else if (delta_is_split(from)) {
if (delta_is_new_only(to)) {
if (best_match->similarity < opts.rename_threshold)
continue;
delta_make_rename(to, from, best_match->similarity);
from->status = (diff->new_src == GIT_ITERATOR_TYPE_WORKDIR) ?
GIT_DELTA_UNTRACKED : GIT_DELTA_ADDED;
memset(&from->old_file, 0, sizeof(from->old_file));
from->old_file.path = from->new_file.path;
from->old_file.flags |= GIT_DIFF_FLAG_VALID_OID;
from->flags &= ~GIT_DIFF_FLAG__TO_SPLIT;
num_rewrites--;
num_updates++;
} else {
assert(delta_is_split(from));
if (best_match->similarity < opts.rename_from_rewrite_threshold)
continue;
memcpy(&swap, &to->old_file, sizeof(swap));
delta_make_rename(to, from, best_match->similarity);
num_rewrites--;
num_updates++;
memcpy(&from->old_file, &swap, sizeof(from->old_file));
/* if we've just swapped the new element into the correct
* place, clear the SPLIT flag
*/
if (match_tgts[j].idx == i &&
match_tgts[j].similarity >
opts.rename_from_rewrite_threshold) {
from->status = GIT_DELTA_RENAMED;
from->similarity = match_tgts[j].similarity;
match_tgts[j].similarity = 0;
from->flags &= ~GIT_DIFF_FLAG__TO_SPLIT;
num_rewrites--;
}
/* otherwise, if we just overwrote a source, update mapping */
else if (j > i && match_srcs[i].similarity > 0) {
match_tgts[match_srcs[i].idx].idx = j;
}
num_updates++;
}
}
else if (delta_is_new_only(to)) {
if (!FLAG_SET(&opts, GIT_DIFF_FIND_COPIES) ||
best_match->similarity < opts.copy_threshold)
continue;
to->status = GIT_DELTA_COPIED;
to->similarity = best_match->similarity;
memcpy(&to->old_file, &from->old_file, sizeof(to->old_file));
num_updates++;
}
}
/*
* Actually split and delete entries as needed
*/
if (num_rewrites > 0 || num_updates > 0)
error = apply_splits_and_deletes(
diff, diff->deltas.length - num_rewrites,
FLAG_SET(&opts, GIT_DIFF_BREAK_REWRITES));
cleanup:
git__free(match_srcs);
git__free(match_tgts);
for (i = 0; i < sigcache_size; ++i) {
if (sigcache[i] != NULL)
opts.metric->free_signature(sigcache[i], opts.metric->payload);
}
git__free(sigcache);
if (!given_opts || !given_opts->metric)
git__free(opts.metric);
return error;
}
#undef FLAG_SET
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