lockfile.c: make lock_file return a meaningful errno on failurei
Making errno when returning from lock_file() meaningful, which should
fix
* an existing almost-bug in lock_ref_sha1_basic where it assumes
errno==ENOENT is meaningful and could waste some work on retries
* an existing bug in repack_without_refs where it prints
strerror(errno) and picks advice based on errno, despite errno
potentially being zero and potentially having been clobbered by
that point
Signed-off-by: Ronnie Sahlberg <sahlberg@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
Acked-by: Michael Haggerty <mhagger@alum.mit.edu>
diff --git a/lockfile.c b/lockfile.c
index 464031b..a921d77 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -121,7 +121,7 @@
return p;
}
-
+/* Make sure errno contains a meaningful value on error */
static int lock_file(struct lock_file *lk, const char *path, int flags)
{
/*
@@ -130,8 +130,10 @@
*/
static const size_t max_path_len = sizeof(lk->filename) - 5;
- if (strlen(path) >= max_path_len)
+ if (strlen(path) >= max_path_len) {
+ errno = ENAMETOOLONG;
return -1;
+ }
strcpy(lk->filename, path);
if (!(flags & LOCK_NODEREF))
resolve_symlink(lk->filename, max_path_len);
@@ -148,9 +150,13 @@
lock_file_list = lk;
lk->on_list = 1;
}
- if (adjust_shared_perm(lk->filename))
- return error("cannot fix permission bits on %s",
- lk->filename);
+ if (adjust_shared_perm(lk->filename)) {
+ int save_errno = errno;
+ error("cannot fix permission bits on %s",
+ lk->filename);
+ errno = save_errno;
+ return -1;
+ }
}
else
lk->filename[0] = 0;
@@ -188,6 +194,7 @@
die("%s", buf.buf);
}
+/* This should return a meaningful errno on failure */
int hold_lock_file_for_update(struct lock_file *lk, const char *path, int flags)
{
int fd = lock_file(lk, path, flags);
diff --git a/refs.c b/refs.c
index db05602..e9d53e4 100644
--- a/refs.c
+++ b/refs.c
@@ -2212,6 +2212,7 @@
return 0;
}
+/* This should return a meaningful errno on failure */
int lock_packed_refs(int flags)
{
struct packed_ref_cache *packed_ref_cache;
diff --git a/refs.h b/refs.h
index 09d3564..64f25d9 100644
--- a/refs.h
+++ b/refs.h
@@ -82,6 +82,7 @@
/*
* Lock the packed-refs file for writing. Flags is passed to
* hold_lock_file_for_update(). Return 0 on success.
+ * Errno is set to something meaningful on error.
*/
extern int lock_packed_refs(int flags);
