chase: tighten flags checks in chase_and_unlinkat()

Some flags don't reasonably apply to chase_and_unlinkat() (because we
open the parent inode of an inode to delete, which is always a dir),
hence let's catch these flags when misused.

(I ran into this, and it was very confusing to debug, hence let's make
it easier)

diff --git a/src/basic/chase.c b/src/basic/chase.c
index 82946eae5f199ab4c9dfb8a7b175dc926ceda209..5abb4bc4307bb2d67f4976a8211c2b4cf0e6d312 100644 (file)
--- a/src/basic/chase.c
+++ b/src/basic/chase.c
@@ -1098,7 +1098,7 @@ int chase_and_unlink(const char *path, const char *root, ChaseFlags chase_flags,
         int r;
 
         assert(path);
-        assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP|CHASE_PARENT)));
+        assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP|CHASE_PARENT|CHASE_MUST_BE_SOCKET|CHASE_MUST_BE_REGULAR|CHASE_MUST_BE_DIRECTORY|CHASE_EXTRACT_FILENAME|CHASE_MKDIR_0755)));
 
         fd = chase_and_open(path, root, chase_flags|CHASE_PARENT|CHASE_NOFOLLOW, O_PATH|O_DIRECTORY|O_CLOEXEC, &p);
         if (fd < 0)
@@ -1312,7 +1312,7 @@ int chase_and_unlinkat(int dir_fd, const char *path, ChaseFlags chase_flags, int
         int r;
 
         assert(path);
-        assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP|CHASE_PARENT)));
+        assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP|CHASE_PARENT|CHASE_MUST_BE_SOCKET|CHASE_MUST_BE_REGULAR|CHASE_MUST_BE_DIRECTORY|CHASE_EXTRACT_FILENAME|CHASE_MKDIR_0755)));
 
         fd = chase_and_openat(dir_fd, path, chase_flags|CHASE_PARENT|CHASE_NOFOLLOW, O_PATH|O_DIRECTORY|O_CLOEXEC, &p);
         if (fd < 0)