Move BE_*/LE_*/ST*/LD* macros to a common place. Some further

optimization/cleanup would be desirable (e.g. LE_* and LD*
should be the same on x86).

Originally committed as revision 7218 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 42 insertions, 0 deletions

diff --git a/libavutil/intreadwrite.h b/libavutil/intreadwrite.h
new file mode 100644
index 0000000000..c43f9d6517
--- /dev/null
+++ b/libavutil/intreadwrite.h
@@ -0,0 +1,42 @@
+#ifndef INTREADWRITE_H
+#define INTREADWRITE_H
+
+#ifdef __GNUC__
+
+struct unaligned_64 { uint64_t l; } __attribute__((packed));
+struct unaligned_32 { uint32_t l; } __attribute__((packed));
+struct unaligned_16 { uint16_t l; } __attribute__((packed));
+
+#define LD16(a) (((const struct unaligned_16 *) (a))->l)
+#define LD32(a) (((const struct unaligned_32 *) (a))->l)
+#define LD64(a) (((const struct unaligned_64 *) (a))->l)
+
+#define ST16(a, b) (((struct unaligned_16 *) (a))->l) = (b)
+#define ST32(a, b) (((struct unaligned_32 *) (a))->l) = (b)
+
+#else /* __GNUC__ */
+
+#define LD16(a) (*((uint16_t*)(a)))
+#define LD32(a) (*((uint32_t*)(a)))
+#define LD64(a) (*((uint64_t*)(a)))
+
+#define ST16(a, b) *((uint16_t*)(a)) = (b)
+#define ST32(a, b) *((uint32_t*)(a)) = (b)
+
+#endif /* !__GNUC__ */
+
+/* endian macros */
+#if !defined(BE_16) || !defined(BE_32) || !defined(LE_16) || !defined(LE_32)
+#define BE_16(x)  ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
+#define BE_32(x)  ((((uint8_t*)(x))[0] << 24) | \
+                   (((uint8_t*)(x))[1] << 16) | \
+                   (((uint8_t*)(x))[2] << 8) | \
+                    ((uint8_t*)(x))[3])
+#define LE_16(x)  ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
+#define LE_32(x)  ((((uint8_t*)(x))[3] << 24) | \
+                   (((uint8_t*)(x))[2] << 16) | \
+                   (((uint8_t*)(x))[1] << 8) | \
+                    ((uint8_t*)(x))[0])
+#endif
+
+#endif /* INTREADWRITE_H */