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00023 #ifndef AVCODEC_BYTESTREAM_H
00024 #define AVCODEC_BYTESTREAM_H
00025
00026 #include <string.h>
00027
00028 #include "libavutil/common.h"
00029 #include "libavutil/intreadwrite.h"
00030
00031 typedef struct {
00032 const uint8_t *buffer, *buffer_end, *buffer_start;
00033 } GetByteContext;
00034
00035 typedef struct {
00036 uint8_t *buffer, *buffer_end, *buffer_start;
00037 int eof;
00038 } PutByteContext;
00039
00040 #define DEF_T(type, name, bytes, read, write) \
00041 static av_always_inline type bytestream_get_ ## name(const uint8_t **b) \
00042 { \
00043 (*b) += bytes; \
00044 return read(*b - bytes); \
00045 } \
00046 static av_always_inline void bytestream_put_ ## name(uint8_t **b, \
00047 const type value) \
00048 { \
00049 write(*b, value); \
00050 (*b) += bytes; \
00051 } \
00052 static av_always_inline void bytestream2_put_ ## name ## u(PutByteContext *p, \
00053 const type value) \
00054 { \
00055 bytestream_put_ ## name(&p->buffer, value); \
00056 } \
00057 static av_always_inline void bytestream2_put_ ## name(PutByteContext *p, \
00058 const type value) \
00059 { \
00060 if (!p->eof && (p->buffer_end - p->buffer >= bytes)) { \
00061 write(p->buffer, value); \
00062 p->buffer += bytes; \
00063 } else \
00064 p->eof = 1; \
00065 } \
00066 static av_always_inline type bytestream2_get_ ## name ## u(GetByteContext *g) \
00067 { \
00068 return bytestream_get_ ## name(&g->buffer); \
00069 } \
00070 static av_always_inline type bytestream2_get_ ## name(GetByteContext *g) \
00071 { \
00072 if (g->buffer_end - g->buffer < bytes) \
00073 return 0; \
00074 return bytestream2_get_ ## name ## u(g); \
00075 } \
00076 static av_always_inline type bytestream2_peek_ ## name(GetByteContext *g) \
00077 { \
00078 if (g->buffer_end - g->buffer < bytes) \
00079 return 0; \
00080 return read(g->buffer); \
00081 }
00082
00083 #define DEF(name, bytes, read, write) \
00084 DEF_T(unsigned int, name, bytes, read, write)
00085 #define DEF64(name, bytes, read, write) \
00086 DEF_T(uint64_t, name, bytes, read, write)
00087
00088 DEF64(le64, 8, AV_RL64, AV_WL64)
00089 DEF (le32, 4, AV_RL32, AV_WL32)
00090 DEF (le24, 3, AV_RL24, AV_WL24)
00091 DEF (le16, 2, AV_RL16, AV_WL16)
00092 DEF64(be64, 8, AV_RB64, AV_WB64)
00093 DEF (be32, 4, AV_RB32, AV_WB32)
00094 DEF (be24, 3, AV_RB24, AV_WB24)
00095 DEF (be16, 2, AV_RB16, AV_WB16)
00096 DEF (byte, 1, AV_RB8 , AV_WB8 )
00097
00098 #undef DEF
00099 #undef DEF64
00100 #undef DEF_T
00101
00102 #if HAVE_BIGENDIAN
00103 # define bytestream2_get_ne16 bytestream2_get_be16
00104 # define bytestream2_get_ne24 bytestream2_get_be24
00105 # define bytestream2_get_ne32 bytestream2_get_be32
00106 # define bytestream2_get_ne64 bytestream2_get_be64
00107 # define bytestream2_get_ne16u bytestream2_get_be16u
00108 # define bytestream2_get_ne24u bytestream2_get_be24u
00109 # define bytestream2_get_ne32u bytestream2_get_be32u
00110 # define bytestream2_get_ne64u bytestream2_get_be64u
00111 # define bytestream2_put_ne16 bytestream2_put_be16
00112 # define bytestream2_put_ne24 bytestream2_put_be24
00113 # define bytestream2_put_ne32 bytestream2_put_be32
00114 # define bytestream2_put_ne64 bytestream2_put_be64
00115 # define bytestream2_peek_ne16 bytestream2_peek_be16
00116 # define bytestream2_peek_ne24 bytestream2_peek_be24
00117 # define bytestream2_peek_ne32 bytestream2_peek_be32
00118 # define bytestream2_peek_ne64 bytestream2_peek_be64
00119 #else
00120 # define bytestream2_get_ne16 bytestream2_get_le16
00121 # define bytestream2_get_ne24 bytestream2_get_le24
00122 # define bytestream2_get_ne32 bytestream2_get_le32
00123 # define bytestream2_get_ne64 bytestream2_get_le64
00124 # define bytestream2_get_ne16u bytestream2_get_le16u
00125 # define bytestream2_get_ne24u bytestream2_get_le24u
00126 # define bytestream2_get_ne32u bytestream2_get_le32u
00127 # define bytestream2_get_ne64u bytestream2_get_le64u
00128 # define bytestream2_put_ne16 bytestream2_put_le16
00129 # define bytestream2_put_ne24 bytestream2_put_le24
00130 # define bytestream2_put_ne32 bytestream2_put_le32
00131 # define bytestream2_put_ne64 bytestream2_put_le64
00132 # define bytestream2_peek_ne16 bytestream2_peek_le16
00133 # define bytestream2_peek_ne24 bytestream2_peek_le24
00134 # define bytestream2_peek_ne32 bytestream2_peek_le32
00135 # define bytestream2_peek_ne64 bytestream2_peek_le64
00136 #endif
00137
00138 static av_always_inline void bytestream2_init(GetByteContext *g,
00139 const uint8_t *buf,
00140 int buf_size)
00141 {
00142 g->buffer = buf;
00143 g->buffer_start = buf;
00144 g->buffer_end = buf + buf_size;
00145 }
00146
00147 static av_always_inline void bytestream2_init_writer(PutByteContext *p,
00148 uint8_t *buf,
00149 int buf_size)
00150 {
00151 p->buffer = buf;
00152 p->buffer_start = buf;
00153 p->buffer_end = buf + buf_size;
00154 p->eof = 0;
00155 }
00156
00157 static av_always_inline unsigned int bytestream2_get_bytes_left(GetByteContext *g)
00158 {
00159 return g->buffer_end - g->buffer;
00160 }
00161
00162 static av_always_inline unsigned int bytestream2_get_bytes_left_p(PutByteContext *p)
00163 {
00164 return p->buffer_end - p->buffer;
00165 }
00166
00167 static av_always_inline void bytestream2_skip(GetByteContext *g,
00168 unsigned int size)
00169 {
00170 g->buffer += FFMIN(g->buffer_end - g->buffer, size);
00171 }
00172
00173 static av_always_inline void bytestream2_skipu(GetByteContext *g,
00174 unsigned int size)
00175 {
00176 g->buffer += size;
00177 }
00178
00179 static av_always_inline void bytestream2_skip_p(PutByteContext *p,
00180 unsigned int size)
00181 {
00182 int size2;
00183 if (p->eof)
00184 return;
00185 size2 = FFMIN(p->buffer_end - p->buffer, size);
00186 if (size2 != size)
00187 p->eof = 1;
00188 p->buffer += size2;
00189 }
00190
00191 static av_always_inline int bytestream2_tell(GetByteContext *g)
00192 {
00193 return (int)(g->buffer - g->buffer_start);
00194 }
00195
00196 static av_always_inline int bytestream2_tell_p(PutByteContext *p)
00197 {
00198 return (int)(p->buffer - p->buffer_start);
00199 }
00200
00201 static av_always_inline int bytestream2_seek(GetByteContext *g,
00202 int offset,
00203 int whence)
00204 {
00205 switch (whence) {
00206 case SEEK_CUR:
00207 offset = av_clip(offset, -(g->buffer - g->buffer_start),
00208 g->buffer_end - g->buffer);
00209 g->buffer += offset;
00210 break;
00211 case SEEK_END:
00212 offset = av_clip(offset, -(g->buffer_end - g->buffer_start), 0);
00213 g->buffer = g->buffer_end + offset;
00214 break;
00215 case SEEK_SET:
00216 offset = av_clip(offset, 0, g->buffer_end - g->buffer_start);
00217 g->buffer = g->buffer_start + offset;
00218 break;
00219 default:
00220 return AVERROR(EINVAL);
00221 }
00222 return bytestream2_tell(g);
00223 }
00224
00225 static av_always_inline int bytestream2_seek_p(PutByteContext *p,
00226 int offset,
00227 int whence)
00228 {
00229 p->eof = 0;
00230 switch (whence) {
00231 case SEEK_CUR:
00232 if (p->buffer_end - p->buffer < offset)
00233 p->eof = 1;
00234 offset = av_clip(offset, -(p->buffer - p->buffer_start),
00235 p->buffer_end - p->buffer);
00236 p->buffer += offset;
00237 break;
00238 case SEEK_END:
00239 if (offset > 0)
00240 p->eof = 1;
00241 offset = av_clip(offset, -(p->buffer_end - p->buffer_start), 0);
00242 p->buffer = p->buffer_end + offset;
00243 break;
00244 case SEEK_SET:
00245 if (p->buffer_end - p->buffer_start < offset)
00246 p->eof = 1;
00247 offset = av_clip(offset, 0, p->buffer_end - p->buffer_start);
00248 p->buffer = p->buffer_start + offset;
00249 break;
00250 default:
00251 return AVERROR(EINVAL);
00252 }
00253 return bytestream2_tell_p(p);
00254 }
00255
00256 static av_always_inline unsigned int bytestream2_get_buffer(GetByteContext *g,
00257 uint8_t *dst,
00258 unsigned int size)
00259 {
00260 int size2 = FFMIN(g->buffer_end - g->buffer, size);
00261 memcpy(dst, g->buffer, size2);
00262 g->buffer += size2;
00263 return size2;
00264 }
00265
00266 static av_always_inline unsigned int bytestream2_get_bufferu(GetByteContext *g,
00267 uint8_t *dst,
00268 unsigned int size)
00269 {
00270 memcpy(dst, g->buffer, size);
00271 g->buffer += size;
00272 return size;
00273 }
00274
00275 static av_always_inline unsigned int bytestream2_put_buffer(PutByteContext *p,
00276 const uint8_t *src,
00277 unsigned int size)
00278 {
00279 int size2;
00280 if (p->eof)
00281 return 0;
00282 size2 = FFMIN(p->buffer_end - p->buffer, size);
00283 if (size2 != size)
00284 p->eof = 1;
00285 memcpy(p->buffer, src, size2);
00286 p->buffer += size2;
00287 return size2;
00288 }
00289
00290 static av_always_inline unsigned int bytestream2_put_bufferu(PutByteContext *p,
00291 const uint8_t *src,
00292 unsigned int size)
00293 {
00294 memcpy(p->buffer, src, size);
00295 p->buffer += size;
00296 return size;
00297 }
00298
00299 static av_always_inline void bytestream2_set_buffer(PutByteContext *p,
00300 const uint8_t c,
00301 unsigned int size)
00302 {
00303 int size2;
00304 if (p->eof)
00305 return;
00306 size2 = FFMIN(p->buffer_end - p->buffer, size);
00307 if (size2 != size)
00308 p->eof = 1;
00309 memset(p->buffer, c, size2);
00310 p->buffer += size2;
00311 }
00312
00313 static av_always_inline void bytestream2_set_bufferu(PutByteContext *p,
00314 const uint8_t c,
00315 unsigned int size)
00316 {
00317 memset(p->buffer, c, size);
00318 p->buffer += size;
00319 }
00320
00321 static av_always_inline unsigned int bytestream2_get_eof(PutByteContext *p)
00322 {
00323 return p->eof;
00324 }
00325
00326 static av_always_inline unsigned int bytestream_get_buffer(const uint8_t **b,
00327 uint8_t *dst,
00328 unsigned int size)
00329 {
00330 memcpy(dst, *b, size);
00331 (*b) += size;
00332 return size;
00333 }
00334
00335 static av_always_inline void bytestream_put_buffer(uint8_t **b,
00336 const uint8_t *src,
00337 unsigned int size)
00338 {
00339 memcpy(*b, src, size);
00340 (*b) += size;
00341 }
00342
00343 #endif
