Allow all free functions to be called on null

4 files changed, 14 insertions, 6 deletions

diff --git a/src/ring.c b/src/ring.c
index 6e26ebc..4a4692f 100644
--- a/src/ring.c
+++ b/src/ring.c
@@ -80,8 +80,10 @@ zix_ring_new(uint32_t size)
 void
 zix_ring_free(ZixRing* ring)
 {
-  free(ring->buf);
-  free(ring);
+  if (ring) {
+    free(ring->buf);
+    free(ring);
+  }
 }
 
 void
diff --git a/src/strindex.c b/src/strindex.c
index 6443a59..9a6d952 100644
--- a/src/strindex.c
+++ b/src/strindex.c
@@ -82,10 +82,12 @@ zix_strindex_free_rec(ZixStrindexNode* n)
 void
 zix_strindex_free(ZixStrindex* strindex)
 {
-  zix_strindex_free_rec(strindex->root);
-  free(strindex->s);
-  free(strindex->root);
-  free(strindex);
+  if (strindex) {
+    zix_strindex_free_rec(strindex->root);
+    free(strindex->s);
+    free(strindex->root);
+    free(strindex);
+  }
 }
 
 static inline int
diff --git a/test/ring_test.c b/test/ring_test.c
index d4d2d38..24163fe 100644
--- a/test/ring_test.c
+++ b/test/ring_test.c
@@ -129,6 +129,8 @@ main(int argc, char** argv)
     n_writes = (unsigned)atoi(argv[2]);
   }
 
+  zix_ring_free(NULL);
+
   printf("Testing %u writes of %d ints to a %u int ring...\n",
          n_writes,
          MSG_SIZE,
diff --git a/test/strindex_test.c b/test/strindex_test.c
index 42d3c66..3cdfb25 100644
--- a/test/strindex_test.c
+++ b/test/strindex_test.c
@@ -37,6 +37,8 @@ test_fail(const char* fmt, ...)
 int
 main(void)
 {
+  zix_strindex_free(NULL);
+
   const char*  str      = "BANANA";
   const size_t str_len  = strlen(str);
   ZixStrindex* strindex = zix_strindex_new(str);