/* * Bytestream functions * copyright (c) 2006 Baptiste Coudurier * Copyright (c) 2012 Aneesh Dogra (lionaneesh) * * 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 AVCODEC_BYTESTREAM_H #define AVCODEC_BYTESTREAM_H #include #include #include "libavutil/avassert.h" #include "libavutil/common.h" #include "libavutil/intreadwrite.h" typedef struct GetByteContext { const uint8_t *buffer, *buffer_end, *buffer_start; } GetByteContext; typedef struct PutByteContext { uint8_t *buffer, *buffer_end, *buffer_start; int eof; } PutByteContext; #define DEF(type, name, bytes, read, write) \ static av_always_inline type bytestream_get_ ## name(const uint8_t **b) \ { \ (*b) += bytes; \ return read(*b - bytes); \ } \ static av_always_inline void bytestream_put_ ## name(uint8_t **b, \ const type value) \ { \ write(*b, value); \ (*b) += bytes; \ } \ static av_always_inline void bytestream2_put_ ## name ## u(PutByteContext *p, \ const type value) \ { \ bytestream_put_ ## name(&p->buffer, value); \ } \ static av_always_inline void bytestream2_put_ ## name(PutByteContext *p, \ const type value) \ { \ if (!p->eof && (p->buffer_end - p->buffer >= bytes)) { \ write(p->buffer, value); \ p->buffer += bytes; \ } else \ p->eof = 1; \ } \ static av_always_inline type bytestream2_get_ ## name ## u(GetByteContext *g) \ { \ return bytestream_get_ ## name(&g->buffer); \ } \ static av_always_inline type bytestream2_get_ ## name(GetByteContext *g) \ { \ if (g->buffer_end - g->buffer < bytes) { \ g->buffer = g->buffer_end; \ return 0; \ } \ return bytestream2_get_ ## name ## u(g); \ } \ static av_always_inline type bytestream2_peek_ ## name(GetByteContext *g) \ { \ if (g->buffer_end - g->buffer < bytes) \ return 0; \ return read(g->buffer); \ } DEF(uint64_t, le64, 8, AV_RL64, AV_WL64) DEF(unsigned int, le32, 4, AV_RL32, AV_WL32) DEF(unsigned int, le24, 3, AV_RL24, AV_WL24) DEF(unsigned int, le16, 2, AV_RL16, AV_WL16) DEF(uint64_t, be64, 8, AV_RB64, AV_WB64) DEF(unsigned int, be32, 4, AV_RB32, AV_WB32) DEF(unsigned int, be24, 3, AV_RB24, AV_WB24) DEF(unsigned int, be16, 2, AV_RB16, AV_WB16) DEF(unsigned int, byte, 1, AV_RB8 , AV_WB8) #if HAVE_BIGENDIAN # define bytestream2_get_ne16 bytestream2_get_be16 # define bytestream2_get_ne24 bytestream2_get_be24 # define bytestream2_get_ne32 bytestream2_get_be32 # define bytestream2_get_ne64 bytestream2_get_be64 # define bytestream2_get_ne16u bytestream2_get_be16u # define bytestream2_get_ne24u bytestream2_get_be24u # define bytestream2_get_ne32u bytestream2_get_be32u # define bytestream2_get_ne64u bytestream2_get_be64u # define bytestream2_put_ne16 bytestream2_put_be16 # define bytestream2_put_ne24 bytestream2_put_be24 # define bytestream2_put_ne32 bytestream2_put_be32 # define bytestream2_put_ne64 bytestream2_put_be64 # define bytestream2_peek_ne16 bytestream2_peek_be16 # define bytestream2_peek_ne24 bytestream2_peek_be24 # define bytestream2_peek_ne32 bytestream2_peek_be32 # define bytestream2_peek_ne64 bytestream2_peek_be64 #else # define bytestream2_get_ne16 bytestream2_get_le16 # define bytestream2_get_ne24 bytestream2_get_le24 # define bytestream2_get_ne32 bytestream2_get_le32 # define bytestream2_get_ne64 bytestream2_get_le64 # define bytestream2_get_ne16u bytestream2_get_le16u # define bytestream2_get_ne24u bytestream2_get_le24u # define bytestream2_get_ne32u bytestream2_get_le32u # define bytestream2_get_ne64u bytestream2_get_le64u # define bytestream2_put_ne16 bytestream2_put_le16 # define bytestream2_put_ne24 bytestream2_put_le24 # define bytestream2_put_ne32 bytestream2_put_le32 # define bytestream2_put_ne64 bytestream2_put_le64 # define bytestream2_peek_ne16 bytestream2_peek_le16 # define bytestream2_peek_ne24 bytestream2_peek_le24 # define bytestream2_peek_ne32 bytestream2_peek_le32 # define bytestream2_peek_ne64 bytestream2_peek_le64 #endif static av_always_inline void bytestream2_init(GetByteContext *g, const uint8_t *buf, int buf_size) { av_assert0(buf_size >= 0); g->buffer = buf; g->buffer_start = buf; g->buffer_end = buf + buf_size; } static av_always_inline void bytestream2_init_writer(PutByteContext *p, uint8_t *buf, int buf_size) { av_assert0(buf_size >= 0); p->buffer = buf; p->buffer_start = buf; p->buffer_end = buf + buf_size; p->eof = 0; } static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g) { return g->buffer_end - g->buffer; } static av_always_inline unsigned int bytestream2_get_bytes_left_p(PutByteContext *p) { return p->buffer_end - p->buffer; } static av_always_inline void bytestream2_skip(GetByteContext *g, unsigned int size) { g->buffer += FFMIN((unsigned int)(g->buffer_end - g->buffer), size); } static av_always_inline void bytestream2_skipu(GetByteContext *g, unsigned int size) { g->buffer += size; } static av_always_inline void bytestream2_skip_p(PutByteContext *p, unsigned int size) { unsigned int size2; if (p->eof) return; size2 = FFMIN((unsigned int)(p->buffer_end - p->buffer), size); if (size2 != size) p->eof = 1; p->buffer += size2; } static av_always_inline int bytestream2_tell(GetByteContext *g) { return (int)(g->buffer - g->buffer_start); } static av_always_inline int bytestream2_tell_p(PutByteContext *p) { return (int)(p->buffer - p->buffer_start); } static av_always_inline int bytestream2_size(GetByteContext *g) { return (int)(g->buffer_end - g->buffer_start); } static av_always_inline int bytestream2_size_p(PutByteContext *p) { return (int)(p->buffer_end - p->buffer_start); } static av_always_inline int bytestream2_seek(GetByteContext *g, int offset, int whence) { switch (whence) { case SEEK_CUR: offset = av_clip(offset, -(g->buffer - g->buffer_start), g->buffer_end - g->buffer); g->buffer += offset; break; case SEEK_END: offset = av_clip(offset, -(g->buffer_end - g->buffer_start), 0); g->buffer = g->buffer_end + offset; break; case SEEK_SET: offset = av_clip(offset, 0, g->buffer_end - g->buffer_start); g->buffer = g->buffer_start + offset; break; default: return AVERROR(EINVAL); } return bytestream2_tell(g); } static av_always_inline int bytestream2_seek_p(PutByteContext *p, int offset, int whence) { p->eof = 0; switch (whence) { case SEEK_CUR: if (p->buffer_end - p->buffer < offset) p->eof = 1; offset = av_clip(offset, -(p->buffer - p->buffer_start), p->buffer_end - p->buffer); p->buffer += offset; break; case SEEK_END: if (offset > 0) p->eof = 1; offset = av_clip(offset, -(p->buffer_end - p->buffer_start), 0); p->buffer = p->buffer_end + offset; break; case SEEK_SET: if (p->buffer_end - p->buffer_start < offset) p->eof = 1; offset = av_clip(offset, 0, p->buffer_end - p->buffer_start); p->buffer = p->buffer_start + offset; break; default: return AVERROR(EINVAL); } return bytestream2_tell_p(p); } static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g, uint8_t *dst, unsigned int size) { unsigned int size2 = FFMIN((unsigned int)(g->buffer_end - g->buffer), size); memcpy(dst, g->buffer, size2); g->buffer += size2; return size2; } static av_always_inline unsigned int bytestream2_get_bufferu(GetByteContext *g, uint8_t *dst, unsigned int size) { memcpy(dst, g->buffer, size); g->buffer += size; return size; } static av_always_inline unsigned int bytestream2_put_buffer(PutByteContext *p, const uint8_t *src, unsigned int size) { unsigned int size2; if (p->eof) return 0; size2 = FFMIN((unsigned int)(p->buffer_end - p->buffer), size); if (size2 != size) p->eof = 1; memcpy(p->buffer, src, size2); p->buffer += size2; return size2; } static av_always_inline unsigned int bytestream2_put_bufferu(PutByteContext *p, const uint8_t *src, unsigned int size) { memcpy(p->buffer, src, size); p->buffer += size; return size; } static av_always_inline void bytestream2_set_buffer(PutByteContext *p, const uint8_t c, unsigned int size) { unsigned int size2; if (p->eof) return; size2 = FFMIN((unsigned int)(p->buffer_end - p->buffer), size); if (size2 != size) p->eof = 1; memset(p->buffer, c, size2); p->buffer += size2; } static av_always_inline void bytestream2_set_bufferu(PutByteContext *p, const uint8_t c, unsigned int size) { memset(p->buffer, c, size); p->buffer += size; } static av_always_inline unsigned int bytestream2_get_eof(PutByteContext *p) { return p->eof; } static av_always_inline unsigned int bytestream2_copy_bufferu(PutByteContext *p, GetByteContext *g, unsigned int size) { memcpy(p->buffer, g->buffer, size); p->buffer += size; g->buffer += size; return size; } static av_always_inline unsigned int bytestream2_copy_buffer(PutByteContext *p, GetByteContext *g, unsigned int size) { unsigned int size2; if (p->eof) return 0; size = FFMIN((unsigned int)(g->buffer_end - g->buffer), size); size2 = FFMIN((unsigned int)(p->buffer_end - p->buffer), size); if (size2 != size) p->eof = 1; return bytestream2_copy_bufferu(p, g, size2); } static av_always_inline unsigned int bytestream_get_buffer(const uint8_t **b, uint8_t *dst, unsigned int size) { memcpy(dst, *b, size); (*b) += size; return size; } static av_always_inline void bytestream_put_buffer(uint8_t **b, const uint8_t *src, unsigned int size) { memcpy(*b, src, size); (*b) += size; } #endif /* AVCODEC_BYTESTREAM_H */