Both function ease allocating large arrays implementing the overflow
check inside it
Since pointless memsetting a potential large array is a waste of time
the av_malloc_array is provided along with the av_calloc version.
---
libavutil/mem.h | 38 ++++++++++++++++++++++++++++++++++++--
1 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/libavutil/mem.h b/libavutil/mem.h
index cd8490b..4a15b87 100644
--- a/libavutil/mem.h
+++ b/libavutil/mem.h
@@ -63,9 +63,9 @@
#endif
#if AV_GCC_VERSION_AT_LEAST(4,3)
- #define av_alloc_size(n) __attribute__((alloc_size(n)))
+ #define av_alloc_size(...) __attribute__((alloc_size(__VA_ARGS__)))
#else
- #define av_alloc_size(n)
+ #define av_alloc_size(...)
#endif
/**
@@ -79,6 +79,22 @@
void *av_malloc(size_t size) av_malloc_attrib av_alloc_size(1);
/**
+ * Helper function to allocate a block of size * nmemb bytes with
+ * using av_malloc()
+ * @param nmemb Number of elements
+ * @param size Size of the single element
+ * @return Pointer to the allocated block, NULL if the block cannot
+ * be allocated.
+ * @see av_malloc()
+ */
+av_alloc_size(1,2) static inline void *av_malloc_array(size_t nmemb, size_t
size)
+{
+ if (size <= 0 || nmemb >= INT_MAX / size)
+ return NULL;
+ return av_malloc(nmemb * size);
+}
+
+/**
* Allocate or reallocate a block of memory.
* If ptr is NULL and size > 0, allocate a new block. If
* size is zero, free the memory block pointed to by ptr.
@@ -113,6 +129,24 @@ void av_free(void *ptr);
void *av_mallocz(size_t size) av_malloc_attrib av_alloc_size(1);
/**
+ * Helper function to allocate a block of size * nmemb bytes with
+ * using av_mallocz()
+ * @param nmemb Number of elements
+ * @param size Size of the single element
+ * @return Pointer to the allocated block, NULL if the block cannot
+ * be allocated.
+ * @see av_mallocz()
+ * @see av_malloc_array()
+ */
+av_alloc_size(1,2) static inline void *av_calloc(size_t nmemb, size_t size)
+{
+ if (size <= 0 || nmemb >= INT_MAX / size)
+ return NULL;
+ return av_mallocz(nmemb * size);
+}
+
+
+/**
* Duplicate the string s.
* @param s string to be duplicated
* @return Pointer to a newly allocated string containing a
--
1.7.8.rc1
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