summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJunio C Hamano <junkio@cox.net>2005-06-04 06:05:57 (GMT)
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-06-05 21:14:58 (GMT)
commitf78c79c5d4486f47dcd69ea7fef93e84051d4496 (patch)
treef14b7a4fb10b95ff4c0d6c7aecb6f05c6b72f8aa
parent49d9e85d1103fe1d0fcb73956643b93acc5c1f4f (diff)
downloadgit-f78c79c5d4486f47dcd69ea7fef93e84051d4496.zip
git-f78c79c5d4486f47dcd69ea7fef93e84051d4496.tar.gz
git-f78c79c5d4486f47dcd69ea7fef93e84051d4496.tar.bz2
[PATCH] diffcore-break.c: various fixes.
This fixes three bugs in the -B heuristics. - Although it was advertised that the initial break criteria used was the same as what diffcore-rename uses, it was using something different. Instead of using smaller of src and dst size to compare with "edit" size, (insertion and deletion), it was using larger of src and dst, unlike the rename/copy detection logic. This caused the parameter to -B to mean something different from the one to -M and -C. To compensate for this change, the default break score is also changed to match that of the default for rename/copy. - The code would have crashed with division by zero when trying to break an originally empty file. - Contrary to what the comment said, the algorithm was breaking small files, only to later merge them together. Signed-off-by: Junio C Hamano <junkio@cox.net> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
-rw-r--r--diffcore-break.c22
-rw-r--r--diffcore.h2
2 files changed, 9 insertions, 15 deletions
diff --git a/diffcore-break.c b/diffcore-break.c
index 8cbb99f..082e4e5 100644
--- a/diffcore-break.c
+++ b/diffcore-break.c
@@ -61,14 +61,7 @@ static int should_break(struct diff_filespec *src,
if (diff_populate_filespec(src, 0) || diff_populate_filespec(dst, 0))
return 0; /* error but caught downstream */
- delta_size = ((src->size < dst->size) ?
- (dst->size - src->size) : (src->size - dst->size));
-
- /* Notice that we use max of src and dst as the base size,
- * unlike rename similarity detection. This is so that we do
- * not mistake a large addition as a complete rewrite.
- */
- base_size = ((src->size < dst->size) ? dst->size : src->size);
+ base_size = ((src->size < dst->size) ? src->size : dst->size);
delta = diff_delta(src->data, src->size,
dst->data, dst->size,
@@ -88,10 +81,11 @@ static int should_break(struct diff_filespec *src,
* less than the minimum, after rename/copy runs.
*/
if (src->size <= src_copied)
- delta_size = 0; /* avoid wrapping around */
- else
+ ; /* all copied, nothing removed */
+ else {
delta_size = src->size - src_copied;
- *merge_score_p = delta_size * MAX_SCORE / src->size;
+ *merge_score_p = delta_size * MAX_SCORE / src->size;
+ }
/* Extent of damage, which counts both inserts and
* deletes.
@@ -174,7 +168,8 @@ void diffcore_break(int break_score)
!S_ISDIR(p->one->mode) && !S_ISDIR(p->two->mode) &&
!strcmp(p->one->path, p->two->path)) {
if (should_break(p->one, p->two,
- break_score, &score)) {
+ break_score, &score) &&
+ MINIMUM_BREAK_SIZE <= p->one->size) {
/* Split this into delete and create */
struct diff_filespec *null_one, *null_two;
struct diff_filepair *dp;
@@ -185,8 +180,7 @@ void diffcore_break(int break_score)
* Also we do not want to break very
* small files.
*/
- if ((score < merge_score) ||
- (p->one->size < MINIMUM_BREAK_SIZE))
+ if (score < merge_score)
score = 0;
/* deletion of one */
diff --git a/diffcore.h b/diffcore.h
index 194d40c..f1b5ca7 100644
--- a/diffcore.h
+++ b/diffcore.h
@@ -17,7 +17,7 @@
*/
#define MAX_SCORE 60000
#define DEFAULT_RENAME_SCORE 30000 /* rename/copy similarity minimum (50%) */
-#define DEFAULT_BREAK_SCORE 59400 /* minimum for break to happen (99%)*/
+#define DEFAULT_BREAK_SCORE 30000 /* minimum for break to happen (50%)*/
#define DEFAULT_MERGE_SCORE 48000 /* maximum for break-merge to happen (80%)*/
#define MINIMUM_BREAK_SIZE 400 /* do not break a file smaller than this */