Electronic Arts Game Multimedia format demuxer (WVE/UV2/etc.)

[ffmpeg] / libavcodec / mem.c

diff --git a/libavcodec/mem.c b/libavcodec/mem.c
index 5799c07744ea5bb671283165894e155fab52110e..9eaa09ed62dbe4bd860528cc64611e9dd2135262 100644 (file)
--- a/libavcodec/mem.c
+++ b/libavcodec/mem.c
@@ -16,7 +16,19 @@
  * License along with this library; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  */
+ 
+/**
+ * @file mem.c
+ * default memory allocator for libavcodec.
+ */
+ 
 #include "avcodec.h"
+
+/* here we can use OS dependant allocation functions */
+#undef malloc
+#undef free
+#undef realloc
+
 #ifdef HAVE_MALLOC_H
 #include <malloc.h>
 #endif
@@ -25,11 +37,22 @@
    memory allocator. You do not need to suppress this file because the
    linker will do it automatically */
 
-/* memory alloc */
-void *av_malloc(int size)
+/** 
+ * Memory allocation of size byte with alignment suitable for all
+ * memory accesses (including vectors if available on the
+ * CPU). av_malloc(0) must return a non NULL pointer.
+ */
+void *av_malloc(unsigned int size)
 {
     void *ptr;
-#if defined (HAVE_MEMALIGN)
+    
+#ifdef MEMALIGN_HACK
+    int diff;
+    ptr = malloc(size+16+1);
+    diff= ((-(int)ptr - 1)&15) + 1;
+    ptr += diff;
+    ((char*)ptr)[-1]= diff;
+#elif defined (HAVE_MEMALIGN) 
     ptr = memalign(16,size);
     /* Why 64? 
        Indeed, we should align it:
@@ -60,19 +83,36 @@ void *av_malloc(int size)
 #else
     ptr = malloc(size);
 #endif
-    if (!ptr)
-        return NULL;
-//fprintf(stderr, "%X %d\n", (int)ptr, size);
-    /* NOTE: this memset should not be present */
-    memset(ptr, 0, size);
     return ptr;
 }
 
+/**
+ * av_realloc semantics (same as glibc): if ptr is NULL and size > 0,
+ * identical to malloc(size). If size is zero, it is identical to
+ * free(ptr) and NULL is returned.  
+ */
+void *av_realloc(void *ptr, unsigned int size)
+{
+#ifdef MEMALIGN_HACK
+    //FIXME this isnt aligned correctly though it probably isnt needed
+    int diff;
+    if(!ptr) return av_malloc(size);
+    diff= ((char*)ptr)[-1];
+    return realloc(ptr - diff, size + diff) + diff;
+#else
+    return realloc(ptr, size);
+#endif
+}
+
 /* NOTE: ptr = NULL is explicetly allowed */
 void av_free(void *ptr)
 {
     /* XXX: this test should not be needed on most libcs */
     if (ptr)
+#ifdef MEMALIGN_HACK
+        free(ptr - ((char*)ptr)[-1]);
+#else
         free(ptr);
+#endif
 }