[PATCH v3 05/25] lockfile: unlock file if lockfile permissions cannot be adjusted

[Michael Haggerty <mhagger@alum.mit.edu>]

If the call to adjust_shared_perm() fails, lock_file returns -1, which
to the caller looks like any other failure to lock the file.  So in
this case, roll back the lockfile before returning so that the lock
file is deleted immediately and the lockfile object is left in a
predictable state (namely, unlocked).  Previously, the lockfile was
retained until process cleanup in this situation.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
---
 lockfile.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/lockfile.c b/lockfile.c
index 1122542..b101f77 100644
--- a/lockfile.c
+++ b/lockfile.c
@@ -148,9 +148,11 @@ static int lock_file(struct lock_file *lk, const char *path, int flags)
 			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)) {
+			error("cannot fix permission bits on %s", lk->filename);
+			rollback_lock_file(lk);
+			return -1;
+		}
 	}
 	else
 		lk->filename[0] = 0;
-- 
1.9.1