memory: respect configured alignment

Move the alignment from GstBuffer to GstMemory.
make sure memory is at least aligned to the configured values.

configure.ac

@@ -556,22 +556,22 @@ dnl bit of a misnomer, but keep the conditional named like this so we don't
 dnl have to change too much elsewhere
 AM_CONDITIONAL(HAVE_CHECK, test "x$BUILD_CHECK" = "xyes")
 
-dnl configure the desired buffer alignment
-AC_ARG_WITH([buffer-alignment],
-  AS_HELP_STRING([--with-buffer-alignment],[8,N,malloc,pagesize (default is 32)]),
+dnl configure the desired memory alignment
+AC_ARG_WITH([memory-alignment],
+  AS_HELP_STRING([--with-memory-alignment],[8,N,malloc,pagesize (default is 32)]),
   [
     if test "x$withval" = "xyes"
     then
-      AC_DEFINE(BUFFER_ALIGNMENT, 32, [Buffer alignment to use])
+      AC_DEFINE(MEMORY_ALIGNMENT, 32, [Memory alignment to use])
     else
       case "${withval}" in
-        malloc) AC_DEFINE(BUFFER_ALIGNMENT_MALLOC, 1, [Buffer alignment by malloc default]) ;;
-        pagesize)  AC_DEFINE(BUFFER_ALIGNMENT_PAGESIZE, 1, [Buffer alignment by pagesize]) ;;
-        *)   AC_DEFINE_UNQUOTED(BUFFER_ALIGNMENT, ${withval}, [Buffer alignment to use]) ;;
+        malloc) AC_DEFINE(MEMORY_ALIGNMENT_MALLOC, 1, [Memory alignment by malloc default]) ;;
+        pagesize)  AC_DEFINE(MEMORY_ALIGNMENT_PAGESIZE, 1, [Memory alignment by pagesize]) ;;
+        *)   AC_DEFINE_UNQUOTED(MEMORY_ALIGNMENT, ${withval}, [Memory alignment to use]) ;;
       esac
     fi
   ], [
-    AC_DEFINE(BUFFER_ALIGNMENT_MALLOC, 1, [Buffer alignment by malloc default]) 
+    AC_DEFINE(MEMORY_ALIGNMENT_MALLOC, 1, [Memory alignment by malloc default]) 
   ]
 )
 
@@ -798,7 +798,7 @@ sed \
     -e 's/.* HAVE_WIN32$/#define HAVE_WIN32 1/' \
     -e 's/.* HAVE_WINSOCK2_H$/#define HAVE_WINSOCK2_H 1/' \
     -e 's/.* HOST_CPU$/#define HOST_CPU "i686"/' \
-    -e 's/.* BUFFER_ALIGNMENT_MALLOC/#define BUFFER_ALIGNMENT_MALLOC 1/' \
+    -e 's/.* MEMORY_ALIGNMENT_MALLOC/#define MEMORY_ALIGNMENT_MALLOC 1/' \
     -e 's/.* LIBDIR$/#ifdef _DEBUG\n#  define LIBDIR PREFIX "\\\\debug\\\\lib"\n#else\n#  define LIBDIR PREFIX "\\\\lib"\n#endif/' \
     -e 's/.* LOCALEDIR$/#define LOCALEDIR PREFIX "\\\\share\\\\locale"/' \
     -e 's/.* PACKAGE$/#define PACKAGE "gstreamer"/' \

gst/gstbuffer.c

@@ -211,35 +211,11 @@ _memory_add (GstBuffer * buffer, GstMemory * mem)
   GST_BUFFER_MEM_LEN (buffer) = len + 1;
 }
 
-#if 0
-/* buffer alignment in bytes - 1
- * an alignment of 7 would be the same as malloc() guarantees
- */
-#ifdef HAVE_POSIX_MEMALIGN
-#if defined(BUFFER_ALIGNMENT_MALLOC)
-static size_t _gst_buffer_data_alignment = 7;
-#elif defined(BUFFER_ALIGNMENT_PAGESIZE)
-static size_t _gst_buffer_data_alignment = 0;
-#elif defined(BUFFER_ALIGNMENT)
-static size_t _gst_buffer_data_alignment = BUFFER_ALIGNMENT - 1;
-#else
-#error "No buffer alignment configured"
-#endif
-#endif /* HAVE_POSIX_MEMALIGN */
-#endif
-
 void
 _gst_buffer_initialize (void)
 {
   if (G_LIKELY (_gst_buffer_type == 0)) {
     _gst_buffer_type = gst_mini_object_register ("GstBuffer");
-#if 0
-#ifdef HAVE_GETPAGESIZE
-#ifdef BUFFER_ALIGNMENT_PAGESIZE
-    _gst_buffer_data_alignment = getpagesize () - 1;
-#endif
-#endif
-#endif
   }
 }
 

gst/gstmemory.c

@@ -63,6 +63,21 @@
 #include "gstmemory.h"
 
 
+/* buffer alignment in bytes - 1
+ * an alignment of 7 would be the same as malloc() guarantees
+ */
+#ifdef HAVE_POSIX_MEMALIGN
+#if defined(MEMORY_ALIGNMENT_MALLOC)
+static size_t _gst_memory_alignment = 7;
+#elif defined(MEMORY_ALIGNMENT_PAGESIZE)
+static size_t _gst_memory_alignment = 0;
+#elif defined(MEMORY_ALIGNMENT)
+static size_t _gst_memory_alignment = MEMORY_ALIGNMENT - 1;
+#else
+#error "No memory alignment configured"
+#endif
+#endif /* HAVE_POSIX_MEMALIGN */
+
 struct _GstMemoryAllocator
 {
   GQuark name;
@@ -131,6 +146,8 @@ _default_mem_new_block (gsize maxsize, gsize align, gsize offset, gsize size)
   gsize aoffset, slice_size;
   guint8 *data;
 
+  /* ensure configured alignment */
+  align |= _gst_memory_alignment;
   /* allocate more to compensate for alignment */
   maxsize += align;
   /* alloc header and data in one block */
@@ -300,6 +317,12 @@ _gst_memory_init (void)
 
   allocators = g_hash_table_new (g_str_hash, g_str_equal);
 
+#ifdef HAVE_GETPAGESIZE
+#ifdef MEMORY_ALIGNMENT_PAGESIZE
+  _gst_memory_alignment = getpagesize () - 1;
+#endif
+#endif
+
   _default_mem_impl =
       gst_memory_allocator_register ("GstMemoryDefault", &_mem_info);