(mpstr_tag mp, boolean free_match)
| 274 | } |
| 275 | |
| 276 | int |
| 277 | sync_buffer(mpstr_tag mp, boolean free_match) |
| 278 | { |
| 279 | /* traverse mp structure without modifying pointers, looking |
| 280 | * for a frame valid header. |
| 281 | * if free_format, valid header must also have the same |
| 282 | * samplerate. |
| 283 | * return number of bytes in mp, before the header |
| 284 | * return -1 if header is not found |
| 285 | */ |
| 286 | int b[] = { 0, 0, 0, 0 }; |
| 287 | int i, pos; |
| 288 | boolean h; |
| 289 | buf buf = mp.tail; |
| 290 | if (null==buf) |
| 291 | return -1; |
| 292 | |
| 293 | pos = buf.pos; |
| 294 | for (i = 0; i < mp.bsize; i++) { |
| 295 | /* get 4 bytes */ |
| 296 | |
| 297 | b[0] = b[1]; |
| 298 | b[1] = b[2]; |
| 299 | b[2] = b[3]; |
| 300 | while (pos >= buf.size) { |
| 301 | buf = buf.next; |
| 302 | pos = buf.pos; |
| 303 | } |
| 304 | b[3] = buf.pnt[pos] & 0xff; |
| 305 | ++pos; |
| 306 | |
| 307 | if (i >= 3) { |
| 308 | Frame fr = mp.fr; |
| 309 | long head; |
| 310 | |
| 311 | head = b[0]; |
| 312 | head <<= 8; |
| 313 | head |= b[1]; |
| 314 | head <<= 8; |
| 315 | head |= b[2]; |
| 316 | head <<= 8; |
| 317 | head |= b[3]; |
| 318 | h = common.head_check(head, fr.lay); |
| 319 | |
| 320 | if (h && free_match) { |
| 321 | /* just to be even more thorough, match the sample rate */ |
| 322 | int mode, stereo, sampling_frequency, lsf; |
| 323 | boolean mpeg25; |
| 324 | |
| 325 | if ((head & (1 << 20))!=0) { |
| 326 | lsf = (head & (1 << 19)) !=0 ? 0x0 : 0x1; |
| 327 | mpeg25 = false; |
| 328 | } |
| 329 | else { |
| 330 | lsf = 1; |
| 331 | mpeg25 = true; |
| 332 | } |
| 333 |
no test coverage detected