FFmpeg/libavutil/intreadwrite.h

/*
 * 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 AVUTIL_INTREADWRITE_H
#define AVUTIL_INTREADWRITE_H

#include <stdint.h>
#include "config.h"
#include "bswap.h"

/*
 * Arch-specific headers can provide any combination of
 * AV_[RW][BLN](16|32|64) macros.  Preprocessor symbols must be
 * defined, even if these are implemented as inline functions.
 */


/*
 * Define AV_[RW]N helper macros to simplify definitions not provided
 * by per-arch headers.
 */

#if   defined(__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 AV_RN(s, p) (((const struct unaligned_##s *) (p))->l)
#   define AV_WN(s, p, v) (((struct unaligned_##s *) (p))->l) = (v)

#elif defined(__DECC)

#   define AV_RN(s, p) (*((const __unaligned uint##s##_t*)(p)))
#   define AV_WN(s, p, v) *((__unaligned uint##s##_t*)(p)) = (v)

#elif HAVE_FAST_UNALIGNED

#   define AV_RN(s, p) (*((const uint##s##_t*)(p)))
#   define AV_WN(s, p, v) *((uint##s##_t*)(p)) = (v)

#else

#ifndef AV_RB16
#define AV_RB16(x)  ((((const uint8_t*)(x))[0] << 8) | \
                      ((const uint8_t*)(x))[1])
#endif
#ifndef AV_WB16
#define AV_WB16(p, d) do { \
                    ((uint8_t*)(p))[1] = (d); \
                    ((uint8_t*)(p))[0] = (d)>>8; } while(0)
#endif

#ifndef AV_RL16
#define AV_RL16(x)  ((((const uint8_t*)(x))[1] << 8) | \
                      ((const uint8_t*)(x))[0])
#endif
#ifndef AV_WL16
#define AV_WL16(p, d) do { \
                    ((uint8_t*)(p))[0] = (d); \
                    ((uint8_t*)(p))[1] = (d)>>8; } while(0)
#endif

#ifndef AV_RB32
#define AV_RB32(x)  ((((const uint8_t*)(x))[0] << 24) | \
                     (((const uint8_t*)(x))[1] << 16) | \
                     (((const uint8_t*)(x))[2] <<  8) | \
                      ((const uint8_t*)(x))[3])
#endif
#ifndef AV_WB32
#define AV_WB32(p, d) do { \
                    ((uint8_t*)(p))[3] = (d); \
                    ((uint8_t*)(p))[2] = (d)>>8; \
                    ((uint8_t*)(p))[1] = (d)>>16; \
                    ((uint8_t*)(p))[0] = (d)>>24; } while(0)
#endif

#ifndef AV_RL32
#define AV_RL32(x) ((((const uint8_t*)(x))[3] << 24) | \
                    (((const uint8_t*)(x))[2] << 16) | \
                    (((const uint8_t*)(x))[1] <<  8) | \
                     ((const uint8_t*)(x))[0])
#endif
#ifndef AV_WL32
#define AV_WL32(p, d) do { \
                    ((uint8_t*)(p))[0] = (d); \
                    ((uint8_t*)(p))[1] = (d)>>8; \
                    ((uint8_t*)(p))[2] = (d)>>16; \
                    ((uint8_t*)(p))[3] = (d)>>24; } while(0)
#endif

#ifndef AV_RB64
#define AV_RB64(x)  (((uint64_t)((const uint8_t*)(x))[0] << 56) | \
                     ((uint64_t)((const uint8_t*)(x))[1] << 48) | \
                     ((uint64_t)((const uint8_t*)(x))[2] << 40) | \
                     ((uint64_t)((const uint8_t*)(x))[3] << 32) | \
                     ((uint64_t)((const uint8_t*)(x))[4] << 24) | \
                     ((uint64_t)((const uint8_t*)(x))[5] << 16) | \
                     ((uint64_t)((const uint8_t*)(x))[6] <<  8) | \
                      (uint64_t)((const uint8_t*)(x))[7])
#endif
#ifndef AV_WB64
#define AV_WB64(p, d) do { \
                    ((uint8_t*)(p))[7] = (d);     \
                    ((uint8_t*)(p))[6] = (d)>>8;  \
                    ((uint8_t*)(p))[5] = (d)>>16; \
                    ((uint8_t*)(p))[4] = (d)>>24; \
                    ((uint8_t*)(p))[3] = (d)>>32; \
                    ((uint8_t*)(p))[2] = (d)>>40; \
                    ((uint8_t*)(p))[1] = (d)>>48; \
                    ((uint8_t*)(p))[0] = (d)>>56; } while(0)
#endif

#ifndef AV_RL64
#define AV_RL64(x)  (((uint64_t)((const uint8_t*)(x))[7] << 56) | \
                     ((uint64_t)((const uint8_t*)(x))[6] << 48) | \
                     ((uint64_t)((const uint8_t*)(x))[5] << 40) | \
                     ((uint64_t)((const uint8_t*)(x))[4] << 32) | \
                     ((uint64_t)((const uint8_t*)(x))[3] << 24) | \
                     ((uint64_t)((const uint8_t*)(x))[2] << 16) | \
                     ((uint64_t)((const uint8_t*)(x))[1] <<  8) | \
                      (uint64_t)((const uint8_t*)(x))[0])
#endif
#ifndef AV_WL64
#define AV_WL64(p, d) do { \
                    ((uint8_t*)(p))[0] = (d);     \
                    ((uint8_t*)(p))[1] = (d)>>8;  \
                    ((uint8_t*)(p))[2] = (d)>>16; \
                    ((uint8_t*)(p))[3] = (d)>>24; \
                    ((uint8_t*)(p))[4] = (d)>>32; \
                    ((uint8_t*)(p))[5] = (d)>>40; \
                    ((uint8_t*)(p))[6] = (d)>>48; \
                    ((uint8_t*)(p))[7] = (d)>>56; } while(0)
#endif

#ifdef WORDS_BIGENDIAN
#   define AV_RN(s, p)    AV_RB##s(p)
#   define AV_WN(s, p, v) AV_WB##s(p, v)
#else
#   define AV_RN(s, p)    AV_RL##s(p)
#   define AV_WN(s, p, v) AV_WL##s(p, v)
#endif

#endif /* HAVE_FAST_UNALIGNED */

#ifndef AV_RN16
#   define AV_RN16(p) AV_RN(16, p)
#endif

#ifndef AV_RN32
#   define AV_RN32(p) AV_RN(32, p)
#endif

#ifndef AV_RN64
#   define AV_RN64(p) AV_RN(64, p)
#endif

#ifndef AV_WN16
#   define AV_WN16(p, v) AV_WN(16, p, v)
#endif

#ifndef AV_WN32
#   define AV_WN32(p, v) AV_WN(32, p, v)
#endif

#ifndef AV_WN64
#   define AV_WN64(p, v) AV_WN(64, p, v)
#endif

#ifdef WORDS_BIGENDIAN
#   define AV_RB(s, p)    AV_RN(s, p)
#   define AV_WB(s, p, v) AV_WN(s, p, v)
#   define AV_RL(s, p)    bswap_##s(AV_RN(s, p))
#   define AV_WL(s, p, v) AV_WN(s, p, bswap_##s(v))
#else
#   define AV_RB(s, p)    bswap_##s(AV_RN(s, p))
#   define AV_WB(s, p, v) AV_WN(s, p, bswap_##s(v))
#   define AV_RL(s, p)    AV_RN(s, p)
#   define AV_WL(s, p, v) AV_WN(s, p, v)
#endif

#define AV_RB8(x)     (((const uint8_t*)(x))[0])
#define AV_WB8(p, d)  do { ((uint8_t*)(p))[0] = (d); } while(0)

#define AV_RL8(x)     AV_RB8(x)
#define AV_WL8(p, d)  AV_WB8(p, d)

#ifndef AV_RB16
#   define AV_RB16(p)    AV_RB(16, p)
#endif
#ifndef AV_WB16
#   define AV_WB16(p, v) AV_WB(16, p, v)
#endif

#ifndef AV_RL16
#   define AV_RL16(p)    AV_RL(16, p)
#endif
#ifndef AV_WL16
#   define AV_WL16(p, v) AV_WL(16, p, v)
#endif

#ifndef AV_RB32
#   define AV_RB32(p)    AV_RB(32, p)
#endif
#ifndef AV_WB32
#   define AV_WB32(p, v) AV_WB(32, p, v)
#endif

#ifndef AV_RL32
#   define AV_RL32(p)    AV_RL(32, p)
#endif
#ifndef AV_WL32
#   define AV_WL32(p, v) AV_WL(32, p, v)
#endif

#ifndef AV_RB64
#   define AV_RB64(p)    AV_RB(64, p)
#endif
#ifndef AV_WB64
#   define AV_WB64(p, v) AV_WB(64, p, v)
#endif

#ifndef AV_RL64
#   define AV_RL64(p)    AV_RL(64, p)
#endif
#ifndef AV_WL64
#   define AV_WL64(p, v) AV_WL(64, p, v)
#endif

#define AV_RB24(x)  ((((const uint8_t*)(x))[0] << 16) | \
                     (((const uint8_t*)(x))[1] <<  8) | \
                      ((const uint8_t*)(x))[2])
#define AV_WB24(p, d) do { \
                    ((uint8_t*)(p))[2] = (d); \
                    ((uint8_t*)(p))[1] = (d)>>8; \
                    ((uint8_t*)(p))[0] = (d)>>16; } while(0)

#define AV_RL24(x)  ((((const uint8_t*)(x))[2] << 16) | \
                     (((const uint8_t*)(x))[1] <<  8) | \
                      ((const uint8_t*)(x))[0])
#define AV_WL24(p, d) do { \
                    ((uint8_t*)(p))[0] = (d); \
                    ((uint8_t*)(p))[1] = (d)>>8; \
                    ((uint8_t*)(p))[2] = (d)>>16; } while(0)

#endif /* AVUTIL_INTREADWRITE_H */