Generic Memory Pools

1. Add API for function `wc_UnloadStaticMemory()` which frees the mutex
   used by the static memory pool.
2. Update the `wc_LoadStaticMemory_ex()` test to free the static memory
   pool's mutex on each successful test case.

Author: ejohnstown

tests/api.c

@@ -744,6 +744,7 @@ static int test_wc_LoadStaticMemory_ex(void)
                 (word32)(sizeof(WOLFSSL_HEAP) + sizeof(WOLFSSL_HEAP_HINT)),
                 0, 1),
             0);
+    wc_UnloadStaticMemory(heap);
 
     /* Success case. */
     heap = NULL;
@@ -752,6 +753,7 @@ static int test_wc_LoadStaticMemory_ex(void)
                 staticMemory, (word32)sizeof(staticMemory),
                 0, 1),
             0);
+    wc_UnloadStaticMemory(heap);
 #endif /* WOLFSSL_STATIC_MEMORY */
     return EXPECT_RESULT();
 }

wolfcrypt/src/memory.c

@@ -729,6 +729,15 @@ int wc_LoadStaticMemory(WOLFSSL_HEAP_HINT** pHint,
 }
 
 
+void wc_UnloadStaticMemory(WOLFSSL_HEAP_HINT* heap)
+{
+    WOLFSSL_ENTER("wc_UnloadStaticMemory");
+    if (heap != NULL && heap->memory != NULL) {
+        wc_FreeMutex(&heap->memory->memory_mutex);
+    }
+}
+
+
 /* returns the size of management memory needed for each bucket.
  * This is memory that is used to keep track of and align memory buckets. */
 int wolfSSL_MemoryPaddingSz(void)

wolfssl/wolfcrypt/memory.h

@@ -222,6 +222,7 @@ WOLFSSL_API int wolfSSL_GetAllocators(wolfSSL_Malloc_cb* mf,
             int flag, int max);
     WOLFSSL_API int wc_LoadStaticMemory(WOLFSSL_HEAP_HINT** pHint,
             unsigned char* buf, unsigned int sz, int flag, int max);
+    WOLFSSL_API void wc_UnloadStaticMemory(WOLFSSL_HEAP_HINT* heap);
 
     WOLFSSL_API int wolfSSL_GetMemStats(WOLFSSL_HEAP* heap,
                                                       WOLFSSL_MEM_STATS* stats);