Move av_fast_{m,re}alloc from lavc to lavu.

libavutil/mem.c

@@ -35,6 +35,7 @@
 #endif
 
 #include "avutil.h"
+#include "common.h"
 #include "intreadwrite.h"
 #include "mem.h"
 
@@ -344,3 +345,35 @@ void av_memcpy_backptr(uint8_t *dst, int back, int cnt)
             *dst = *src;
     }
 }
+
+void *av_fast_realloc(void *ptr, unsigned int *size, size_t min_size)
+{
+    if (min_size < *size)
+        return ptr;
+
+    min_size = FFMAX(17 * min_size / 16 + 32, min_size);
+
+    ptr = av_realloc(ptr, min_size);
+    /* we could set this to the unmodified min_size but this is safer
+     * if the user lost the ptr and uses NULL now
+     */
+    if (!ptr)
+        min_size = 0;
+
+    *size = min_size;
+
+    return ptr;
+}
+
+void av_fast_malloc(void *ptr, unsigned int *size, size_t min_size)
+{
+    void **p = ptr;
+    if (min_size < *size)
+        return;
+    min_size = FFMAX(17 * min_size / 16 + 32, min_size);
+    av_free(*p);
+    *p = av_malloc(min_size);
+    if (!*p)
+        min_size = 0;
+    *size = min_size;
+}