Author: ods15 Date: Sat Nov 18 15:38:19 2006 New Revision: 237 Modified: trunk/libnut/demuxer.c Log: make the search for main header in 4kb chunks instead of 0.5mb chunks to save memory, while still keeping same effectiveness... Modified: trunk/libnut/demuxer.c ============================================================================== --- trunk/libnut/demuxer.c (original) +++ trunk/libnut/demuxer.c Sat Nov 18 15:38:19 2006 @@ -714,17 +714,15 @@ static int find_main_headers(nut_context_t * nut) { int err = 0; uint64_t tmp; - int read_data = 512*1024; + int len = PREALLOC_SIZE; + int read_data = ready_read_buf(nut->i, len); // don't waste cpu by running this check every damn time for EAGAIN - // Except for the first time, to not waste memory - if (!nut->seek_status && ready_read_buf(nut->i, read_data) < read_data && buf_eof(nut->i) == NUT_ERR_EAGAIN) - return NUT_ERR_EAGAIN; - - CHECK(get_bytes(nut->i, 7, &tmp)); - read_data -= 7; - while (read_data--) { - ERROR(ready_read_buf(nut->i, 30) < 1, buf_eof(nut->i)); + if (read_data < len && buf_eof(nut->i) != NUT_ERR_EOF) return buf_eof(nut->i); + + CHECK(get_bytes(nut->i, 7, &tmp)); // true EOF will fail here + len = (read_data -= 7); + while (len--) { tmp = (tmp << 8) | *(nut->i->buf_ptr++); if (tmp == MAIN_STARTCODE) break; // give up if we reach a syncpoint, unless we're searching the file end @@ -743,6 +741,7 @@ ERROR(err, err); // if get_bytes returns EAGAIN or a memory error, check for that } while (tmp != SYNCPOINT_STARTCODE); if (tmp == SYNCPOINT_STARTCODE) { // success! + nut->before_seek = nut->seek_status = 0; nut->last_headers = pos; nut->i->buf_ptr = get_buf(nut->i, nut->last_headers); flush_buf(nut->i); @@ -751,6 +750,11 @@ } // failure + if (len == -1 && (nut->before_seek += read_data) < 512*1024) { + nut->i->buf_ptr -= 7; // rewind 7 bytes, try again + flush_buf(nut->i); + return find_main_headers(nut); + } else nut->before_seek = 0; if (!nut->i->isc.seek) return NUT_ERR_NO_HEADERS; if (!nut->seek_status) { nut->seek_status = 18; // start search at 512kb