offset_t url_fseek(ByteIOContext *s, offset_t offset, int whence) { offset_t offset1; offset_t pos= s->pos - (s->write_flag ? 0 : (s->buf_end - s->buffer)); if (whence != SEEK_CUR && whence != SEEK_SET) return -EINVAL; if (whence == SEEK_CUR) { offset1 = pos + (s->buf_ptr - s->buffer); if (offset == 0) return offset1; offset += offset1; } offset1 = offset - pos; if (!s->must_flush && offset1 >= 0 && offset1 < (s->buf_end - s->buffer)) { /* can do the seek inside the buffer */ s->buf_ptr = s->buffer + offset1; } else { if (!s->seek) return -EPIPE; #ifdef CONFIG_MUXERS if (s->write_flag) { flush_buffer(s); s->must_flush = 1; } else #endif //CONFIG_MUXERS { s->buf_end = s->buffer; } s->buf_ptr = s->buffer; if (s->seek(s->opaque, offset, SEEK_SET) == (offset_t)-EPIPE) return -EPIPE; s->pos = offset; } s->eof_reached = 0; return offset; }