Avoid running lstat(2) on the same cache entry.

[thirdparty/git.git] / diff.c

diff --git a/diff.c b/diff.c
index 5b8afdcb05abd4f634b49adb2f521fc75e220647..d464fe3b20efd13bfc7ed08304eb94aca80fa3d9 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -1510,17 +1510,22 @@ static int reuse_worktree_file(const char *name, const unsigned char *sha1, int
        if (pos < 0)
                return 0;
        ce = active_cache[pos];
-       if ((lstat(name, &st) < 0) ||
-           !S_ISREG(st.st_mode) || /* careful! */
-           ce_match_stat(ce, &st, 0) ||
-           hashcmp(sha1, ce->sha1))
+
+       /*
+        * This is not the sha1 we are looking for, or
+        * unreusable because it is not a regular file.
+        */
+       if (hashcmp(sha1, ce->sha1) || !S_ISREG(ce->ce_mode))
                return 0;
-       /* we return 1 only when we can stat, it is a regular file,
-        * stat information matches, and sha1 recorded in the cache
-        * matches.  I.e. we know the file in the work tree really is
-        * the same as the <name, sha1> pair.
+
+       /*
+        * If ce matches the file in the work tree, we can reuse it.
         */
-       return 1;
+       if (ce_uptodate(ce) ||
+           (!lstat(name, &st) && !ce_match_stat(ce, &st, 0)))
+               return 1;
+
+       return 0;
 }
 
 static int populate_from_stdin(struct diff_filespec *s)