[PATCH v3] preserve mtime of local clone

[Clemens Buchacher <drizzd@aon.at>]

A local clone without hardlinks copies all objects, including dangling
ones, to the new repository. Since the mtimes are renewed, those
dangling objects cannot be pruned by "git gc --prune", even if they
would have been old enough for pruning in the original repository.

Instead, preserve mtime during copy. "git gc --prune" will then work
in the clone just like it did in the original.

Signed-off-by: Clemens Buchacher <drizzd@aon.at>
---

On Sat, Sep 12, 2009 at 08:06:51PM -0700, Junio C Hamano wrote:

> This new feature is not wanted by most of the callers of copy_file(), and
> it is not like they may want to conditionally pass 1 in preserve_times
> someday.  I'd limit the damage like this replacement patch, instead.

You're right. That's much better.

> Is it unreasonable to have a test for this one, by the way?

It's not. Test added.

Clemens

 builtin-clone.c  |    2 +-
 cache.h          |    2 ++
 copy.c           |   21 +++++++++++++++++++++
 t/t5304-prune.sh |   54 +++++++++++++++++++++++++++++++++---------------------
 4 files changed, 57 insertions(+), 22 deletions(-)

diff --git a/builtin-clone.c b/builtin-clone.c
index ad04808..bab2d84 100644
--- a/builtin-clone.c
+++ b/builtin-clone.c
@@ -269,7 +269,7 @@ static void copy_or_link_directory(struct strbuf *src, struct strbuf *dest)
 				die_errno("failed to create link '%s'", dest->buf);
 			option_no_hardlinks = 1;
 		}
-		if (copy_file(dest->buf, src->buf, 0666))
+		if (copy_file_with_time(dest->buf, src->buf, 0666))
 			die_errno("failed to copy file to '%s'", dest->buf);
 	}
 	closedir(dir);
diff --git a/cache.h b/cache.h
index 5fad24c..ee9c98c 100644
--- a/cache.h
+++ b/cache.h
@@ -923,6 +923,8 @@ extern const char *git_mailmap_file;
 extern void maybe_flush_or_die(FILE *, const char *);
 extern int copy_fd(int ifd, int ofd);
 extern int copy_file(const char *dst, const char *src, int mode);
+extern int copy_times(const char *dst, const char *src);
+extern int copy_file_with_time(const char *dst, const char *src, int mode);
 extern ssize_t read_in_full(int fd, void *buf, size_t count);
 extern ssize_t write_in_full(int fd, const void *buf, size_t count);
 extern void write_or_die(int fd, const void *buf, size_t count);
diff --git a/copy.c b/copy.c
index e54d15a..963b481 100644
--- a/copy.c
+++ b/copy.c
@@ -55,3 +55,24 @@ int copy_file(const char *dst, const char *src, int mode)
 
 	return status;
 }
+
+int copy_times(const char *dst, const char *src)
+{
+	struct stat st;
+	struct utimbuf times;
+	if (stat(src, &st) < 0)
+		return -1;
+	times.actime = st.st_atime;
+	times.modtime = st.st_mtime;
+	if (utime(dst, &times) < 0)
+		return -1;
+	return 0;
+}
+
+int copy_file_with_time(const char *dst, const char *src, int mode)
+{
+     int status = copy_file(dst, src, mode);
+     if (!status)
+		return copy_times(dst, src);
+     return status;
+}
diff --git a/t/t5304-prune.sh b/t/t5304-prune.sh
index 55ed7c7..15fd90a 100755
--- a/t/t5304-prune.sh
+++ b/t/t5304-prune.sh
@@ -6,6 +6,17 @@
 test_description='prune'
 . ./test-lib.sh
 
+day=$((60*60*24))
+week=$(($day*7))
+
+add_blob() {
+	before=$(git count-objects | sed "s/ .*//") &&
+	BLOB=$(echo aleph_0 | git hash-object -w --stdin) &&
+	BLOB_FILE=.git/objects/$(echo $BLOB | sed "s/^../&\//") &&
+	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
+	test -f $BLOB_FILE
+}
+
 test_expect_success setup '
 
 	: > file &&
@@ -31,11 +42,7 @@ test_expect_success 'prune stale packs' '
 
 test_expect_success 'prune --expire' '
 
-	before=$(git count-objects | sed "s/ .*//") &&
-	BLOB=$(echo aleph | git hash-object -w --stdin) &&
-	BLOB_FILE=.git/objects/$(echo $BLOB | sed "s/^../&\//") &&
-	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
-	test -f $BLOB_FILE &&
+	add_blob &&
 	git prune --expire=1.hour.ago &&
 	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
 	test -f $BLOB_FILE &&
@@ -48,16 +55,12 @@ test_expect_success 'prune --expire' '
 
 test_expect_success 'gc: implicit prune --expire' '
 
-	before=$(git count-objects | sed "s/ .*//") &&
-	BLOB=$(echo aleph_0 | git hash-object -w --stdin) &&
-	BLOB_FILE=.git/objects/$(echo $BLOB | sed "s/^../&\//") &&
-	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
-	test -f $BLOB_FILE &&
-	test-chmtime =-$((86400*14-30)) $BLOB_FILE &&
+	add_blob &&
+	test-chmtime =-$((2*$week-30)) $BLOB_FILE &&
 	git gc &&
 	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
 	test -f $BLOB_FILE &&
-	test-chmtime =-$((86400*14+1)) $BLOB_FILE &&
+	test-chmtime =-$((2*$week+1)) $BLOB_FILE &&
 	git gc &&
 	test $before = $(git count-objects | sed "s/ .*//") &&
 	! test -f $BLOB_FILE
@@ -114,12 +117,8 @@ test_expect_success 'prune: do not prune heads listed as an argument' '
 
 test_expect_success 'gc --no-prune' '
 
-	before=$(git count-objects | sed "s/ .*//") &&
-	BLOB=$(echo aleph_0 | git hash-object -w --stdin) &&
-	BLOB_FILE=.git/objects/$(echo $BLOB | sed "s/^../&\//") &&
-	test $((1 + $before)) = $(git count-objects | sed "s/ .*//") &&
-	test -f $BLOB_FILE &&
-	test-chmtime =-$((86400*5001)) $BLOB_FILE &&
+	add_blob &&
+	test-chmtime =-$((5001*$day)) $BLOB_FILE &&
 	git config gc.pruneExpire 2.days.ago &&
 	git gc --no-prune &&
 	test 1 = $(git count-objects | sed "s/ .*//") &&
@@ -140,9 +139,8 @@ test_expect_success 'gc respects gc.pruneExpire' '
 
 test_expect_success 'gc --prune=<date>' '
 
-	BLOB=$(echo aleph_0 | git hash-object -w --stdin) &&
-	BLOB_FILE=.git/objects/$(echo $BLOB | sed "s/^../&\//") &&
-	test-chmtime =-$((86400*5001)) $BLOB_FILE &&
+	add_blob &&
+	test-chmtime =-$((5001*$day)) $BLOB_FILE &&
 	git gc --prune=5002.days.ago &&
 	test -f $BLOB_FILE &&
 	git gc --prune=5000.days.ago &&
@@ -150,4 +148,18 @@ test_expect_success 'gc --prune=<date>' '
 
 '
 
+test_expect_success 'gc: prune old objects after local clone' '
+
+	add_blob &&
+	test-chmtime =-$((2*$week+1)) $BLOB_FILE &&
+	git clone --no-hardlinks . aclone &&
+	cd aclone &&
+	test 1 = $(git count-objects | sed "s/ .*//") &&
+	test -f $BLOB_FILE &&
+	git gc --prune &&
+	test 0 = $(git count-objects | sed "s/ .*//") &&
+	! test -f $BLOB_FILE
+
+'
+
 test_done
-- 
1.6.5.rc0.164.g5f6b0