FFmpeg/libavutil/intreadwrite.h
Ramiro Polla 7b829d2ab6 "fast unaligned" bytestream functions
patch by Ramiro Polla ramiro lisha ufsc br
original thread:
date: 03/11/2007 03:06 AM
subject: [Ffmpeg-devel] [PATCH] Machine endian bytestream functions

Originally committed as revision 8803 to svn://svn.ffmpeg.org/ffmpeg/trunk
2007-04-25 08:47:15 +00:00

133 lines
4.4 KiB
C

/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#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 */
#define AV_RB8(x) (((uint8_t*)(x))[0])
#define AV_WB8(p, d) { ((uint8_t*)(p))[0] = (d); }
#define AV_RL8(x) AV_RB8(x)
#define AV_WL8(p, d) AV_WB8(p, d)
#ifdef HAVE_FAST_UNALIGNED
# ifdef WORDS_BIGENDIAN
# define AV_RB16(x) LD16(x)
# define AV_WB16(p, d) ST16(p, d)
# define AV_RL16(x) bswap_16(LD16(x))
# define AV_WL16(p, d) ST16(p, bswap_16(d))
# else /* WORDS_BIGENDIAN */
# define AV_RB16(x) bswap_16(LD16(x))
# define AV_WB16(p, d) ST16(p, bswap_16(d))
# define AV_RL16(x) LD16(x)
# define AV_WL16(p, d) ST16(p, d)
# endif
#else /* HAVE_FAST_UNALIGNED */
#define AV_RB16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
#define AV_WB16(p, d) { \
((uint8_t*)(p))[1] = (d); \
((uint8_t*)(p))[0] = (d)>>8; }
#define AV_RL16(x) ((((uint8_t*)(x))[1] << 8) | \
((uint8_t*)(x))[0])
#define AV_WL16(p, d) { \
((uint8_t*)(p))[0] = (d); \
((uint8_t*)(p))[1] = (d)>>8; }
#endif
#define AV_RB24(x) ((((uint8_t*)(x))[0] << 16) | \
(((uint8_t*)(x))[1] << 8) | \
((uint8_t*)(x))[2])
#define AV_WB24(p, d) { \
((uint8_t*)(p))[2] = (d); \
((uint8_t*)(p))[1] = (d)>>8; \
((uint8_t*)(p))[0] = (d)>>16; }
#define AV_RL24(x) ((((uint8_t*)(x))[2] << 16) | \
(((uint8_t*)(x))[1] << 8) | \
((uint8_t*)(x))[0])
#define AV_WL24(p, d) { \
((uint8_t*)(p))[0] = (d); \
((uint8_t*)(p))[1] = (d)>>8; \
((uint8_t*)(p))[2] = (d)>>16; }
#ifdef HAVE_FAST_UNALIGNED
# ifdef WORDS_BIGENDIAN
# define AV_RB32(x) LD32(x)
# define AV_WB32(p, d) ST32(p, d)
# define AV_RL32(x) bswap_32(LD32(x))
# define AV_WL32(p, d) ST32(p, bswap_32(d))
# else /* WORDS_BIGENDIAN */
# define AV_RB32(x) bswap_32(LD32(x))
# define AV_WB32(p, d) ST32(p, bswap_32(d))
# define AV_RL32(x) LD32(x)
# define AV_WL32(p, d) ST32(p, d)
# endif
#else /* HAVE_FAST_UNALIGNED */
#define AV_RB32(x) ((((uint8_t*)(x))[0] << 24) | \
(((uint8_t*)(x))[1] << 16) | \
(((uint8_t*)(x))[2] << 8) | \
((uint8_t*)(x))[3])
#define AV_WB32(p, d) { \
((uint8_t*)(p))[3] = (d); \
((uint8_t*)(p))[2] = (d)>>8; \
((uint8_t*)(p))[1] = (d)>>16; \
((uint8_t*)(p))[0] = (d)>>24; }
#define AV_RL32(x) ((((uint8_t*)(x))[3] << 24) | \
(((uint8_t*)(x))[2] << 16) | \
(((uint8_t*)(x))[1] << 8) | \
((uint8_t*)(x))[0])
#define AV_WL32(p, d) { \
((uint8_t*)(p))[0] = (d); \
((uint8_t*)(p))[1] = (d)>>8; \
((uint8_t*)(p))[2] = (d)>>16; \
((uint8_t*)(p))[3] = (d)>>24; }
#endif
#endif /* INTREADWRITE_H */