static int find_tag(ByteIOContext *pb, uint32_t tag1) { unsigned int tag; int size; for(;;) { if (url_feof(pb)) return -1; tag = get_le32(pb); size = get_le32(pb); if (tag == tag1) break; url_fseek(pb, size, SEEK_CUR); } if (size < 0) size = 0x7fffffff; return size; }