Terminate diff-* on non-zero exit from GIT_EXTERNAL_DIFF
(slightly updated from the version posted to the GIT mailing list
with small bugfixes).
This patch changes the git-apply-patch-script to exit non-zero when
the patch cannot be applied. Previously, the external diff driver
deliberately ignored the exit status of GIT_EXTERNAL_DIFF command,
which was a design mistake. It now stops the processing when
GIT_EXTERNAL_DIFF exits non-zero, so the damages from running
git-diff-* with git-apply-patch-script between two wrong trees can be
contained.
The "diff" command line generated by the built-in driver is changed to
always exit 0 in order to match this new behaviour. I know Pasky does
not use GIT_EXTERNAL_DIFF yet, so this change should not break Cogito,
either.
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/diff.c b/diff.c
index a4d2b2d..4a54688 100644
--- a/diff.c
+++ b/diff.c
@@ -83,7 +83,7 @@
{
int i, next_at;
const char *diff_cmd = "diff -L'%s%s' -L'%s%s'";
- const char *diff_arg = "'%s' '%s'";
+ const char *diff_arg = "'%s' '%s'||:"; /* "||:" is to return 0 */
const char *input_name_sq[2];
const char *path0[2];
const char *path1[2];
@@ -261,16 +261,20 @@
printf("* Unmerged path %s\n", name);
exit(0);
}
- if (waitpid(pid, &status, 0) < 0 || !WIFEXITED(status)) {
- /* We do not check the exit status because typically
+ if (waitpid(pid, &status, 0) < 0 ||
+ !WIFEXITED(status) || WEXITSTATUS(status)) {
+ /* Earlier we did not check the exit status because
* diff exits non-zero if files are different, and
- * we are not interested in knowing that. We *knew*
- * they are different and that's why we ran diff
- * in the first place! However if it dies by a signal,
- * we stop processing immediately.
+ * we are not interested in knowing that. It was a
+ * mistake which made it harder to quit a diff-*
+ * session that uses the git-apply-patch-script as
+ * the GIT_EXTERNAL_DIFF. A custom GIT_EXTERNAL_DIFF
+ * should also exit non-zero only when it wants to
+ * abort the entire diff-* session.
*/
remove_tempfile();
- die("external diff died unexpectedly.\n");
+ fprintf(stderr, "external diff died, stopping at %s.\n", name);
+ exit(1);
}
remove_tempfile();
}