[PATCH/RFC v1 4/6] use fstat() instead of lstat() when we have an opened file

[Kjetil Barvik <barvik@broadpark.no>]

Currently inside write_entry() we do an lstat(path, &st) call on a
file which have just been opened inside the exact same function.  It
should be better to call fstat(fd, &st) on the file while it is
opened, and it should be at least as fast as the lstat() method.

Signed-off-by: Kjetil Barvik <barvik@broadpark.no>
---
 entry.c |   11 ++++++++---
 1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/entry.c b/entry.c
index 8543755..c932ae8 100644
--- a/entry.c
+++ b/entry.c
@@ -96,11 +96,12 @@ write_entry(struct cache_entry *ce, char *path, const struct checkout *state,
 	    int to_tempfile)
 {
 	unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
-	int fd, ret;
+	int fd, ret, fstat_done = 0;
 	char *new;
 	struct strbuf buf = STRBUF_INIT;
 	unsigned long size;
 	size_t wrote, newsize = 0;
+	struct stat st;
 
 	switch (ce_mode_s_ifmt) {
 	case S_IFREG:
@@ -151,6 +152,10 @@ write_entry(struct cache_entry *ce, char *path, const struct checkout *state,
 		}
 
 		wrote = write_in_full(fd, new, size);
+		if (state->refresh_cache) {
+			fstat(fd, &st);
+			fstat_done = 1;
+		}
 		close(fd);
 		free(new);
 		if (wrote != size)
@@ -174,8 +179,8 @@ write_entry(struct cache_entry *ce, char *path, const struct checkout *state,
 	}
 
 	if (state->refresh_cache) {
-		struct stat st;
-		lstat(ce->name, &st);
+		if (!fstat_done)
+			lstat(ce->name, &st);
 		fill_stat_cache_info(ce, &st);
 	}
 	return 0;
-- 
1.6.1.349.g99fa5