[PATCH 1/7 v2] libsepol: Changes to ebitmap.h to fix compiler warnings

[James Carter <jwcart2@gmail.com>]

When compiling with the "-Wnull-dereference" flag, the compiler is
not smart enough to realize that anytime the ebitmap_t node field is
NULL, the highbit field will equal 0. This causes false positive
warnings to be generated.

Change the ebitmap_is_empty() and ebitmap_length() macros to check
for the node being NULL instead of just relying on the value of
highbit to eliminate these false warnings.

Signed-off-by: James Carter <jwcart2@gmail.com>
---
 libsepol/include/sepol/policydb/ebitmap.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/libsepol/include/sepol/policydb/ebitmap.h b/libsepol/include/sepol/policydb/ebitmap.h
index c434c4ba..7e19c301 100644
--- a/libsepol/include/sepol/policydb/ebitmap.h
+++ b/libsepol/include/sepol/policydb/ebitmap.h
@@ -39,8 +39,8 @@ typedef struct ebitmap {
 	uint32_t highbit;	/* highest position in the total bitmap */
 } ebitmap_t;
 
-#define ebitmap_is_empty(e) (((e)->highbit) == 0)
-#define ebitmap_length(e) ((e)->highbit)
+#define ebitmap_is_empty(e) (((e)->node) == NULL)
+#define ebitmap_length(e) ((e)->node ? (e)->highbit : 0)
 #define ebitmap_startbit(e) ((e)->node ? (e)->node->startbit : 0)
 #define ebitmap_startnode(e) ((e)->node)
 
-- 
2.41.0