path: root/diff.c
diff options
authorJeff King <>2010-09-21 21:01:24 (GMT)
committerJunio C Hamano <>2010-09-24 01:32:32 (GMT)
commitd391c0ff94e1b314b0664db0e8eb5bd92934f9cb (patch)
tree917615d9622c3c4958048e40b3fbef2d57c07c49 /diff.c
parente22148f406a7a31a25ebda01d21d9a4646ce82ea (diff)
diff: don't use pathname-based diff drivers for symlinks
When we're diffing symlinks, we consider the contents to be the pathname that the symlink points to. When a user sets up a userdiff driver like "*.pdf diff=pdf", their "diff.pdf.*" config generally tells us what to do with the content of pdf files. With the current code, we will actually process a symlink like "link.pdf" using a configured pdf driver, meaning we are using contents which consist of a pathname with configuration that is expecting contents that consist of an actual pdf file. The most noticeable example of this would have been textconv; however, it was already protected in its own textconv-specific code path. We can still see the breakage with something like "diff.*.binary", though. You could also see it with diff.*.funcname, though it is a bit harder to trigger accidentally there. This patch adds a check for S_ISREG lower in the callstack than the textconv-specific check, which should block use of any userdiff config for non-regular files. We can drop the check in the textconv code, which is now redundant. Signed-off-by: Jeff King <> Signed-off-by: Junio C Hamano <>
Diffstat (limited to 'diff.c')
1 files changed, 8 insertions, 3 deletions
diff --git a/diff.c b/diff.c
index 19b5bf6..95835d8 100644
--- a/diff.c
+++ b/diff.c
@@ -1764,8 +1764,14 @@ static void emit_binary_diff(FILE *file, mmfile_t *one, mmfile_t *two, char *pre
static void diff_filespec_load_driver(struct diff_filespec *one)
- if (!one->driver)
+ /* Use already-loaded driver */
+ if (one->driver)
+ return;
+ if (S_ISREG(one->mode))
one->driver = userdiff_find_by_path(one->path);
+ /* Fallback to default settings */
if (!one->driver)
one->driver = userdiff_find_by_name("default");
@@ -1813,8 +1819,7 @@ struct userdiff_driver *get_textconv(struct diff_filespec *one)
if (!DIFF_FILE_VALID(one))
return NULL;
- if (!S_ISREG(one->mode))
- return NULL;
if (!one->driver->textconv)
return NULL;