diff --git a/ot_fullscrape.c b/ot_fullscrape.c index 0571049..052777a 100644 --- a/ot_fullscrape.c +++ b/ot_fullscrape.c @@ -25,43 +25,75 @@ size_t return_fullscrape_for_tracker( int *iovec_entries, struct iovec **iovector ) { int bucket; - size_t j; char *r, *re; + /* Setup return vector */ *iovec_entries = 0; if( !( r = iovec_increase( iovec_entries, iovector, OT_SCRAPE_CHUNK_SIZE ) ) ) return 0; + + /* ... and pointer end of current output buffer + this works as a low watermark */ re = r + OT_SCRAPE_CHUNK_SIZE; + /* Start reply dictionary */ memmove( r, "d5:filesd", 9 ); r += 9; + + /* For each bucket... */ for( bucket=0; bucketsize; ++j ) { - ot_peerlist *peer_list = ( ((ot_torrent*)(torrents_list->data))[j] ).peer_list; - ot_hash *hash =&( ((ot_torrent*)(torrents_list->data))[j] ).hash; + size_t tor_offset; + + /* For each torrent in this bucket.. */ + for( tor_offset=0; tor_offsetsize; ++tor_offset ) { + /* Address torrents members */ + ot_peerlist *peer_list = ( ((ot_torrent*)(torrents_list->data))[tor_offset] ).peer_list; + ot_hash *hash =&( ((ot_torrent*)(torrents_list->data))[tor_offset] ).hash; + + /* If torrent has peers or download count, its interesting */ if( peer_list->peer_count || peer_list->down_count ) { + + /* push hash as bencoded string */ *r++='2'; *r++='0'; *r++=':'; memmove( r, hash, 20 ); r+=20; + + /* push rest of the scrape string */ r += sprintf( r, "d8:completei%zde10:downloadedi%zde10:incompletei%zdee", peer_list->seed_count, peer_list->down_count, peer_list->peer_count-peer_list->seed_count ); } + /* If we reached our low watermark in buffer... */ if( re - r <= OT_FULLSCRAPE_MAXENTRYLEN ) { + + /* crop current output buffer to the amount really used */ iovec_fixlast( iovec_entries, iovector, OT_SCRAPE_CHUNK_SIZE - ( re - r ) ); + + /* And allocate a fresh output buffer at the end of our buffers list */ if( !( r = iovec_increase( iovec_entries, iovector, OT_SCRAPE_CHUNK_SIZE ) ) ) { + + /* If this fails: free buffers */ iovec_free( iovec_entries, iovector ); + + /* Release lock on current bucket and return */ mutex_bucket_unlock( bucket ); return 0; } + + /* Adjust new end of output buffer */ re = r + OT_SCRAPE_CHUNK_SIZE; } - } + + /* All torrents done: release lock on currenct bucket */ mutex_bucket_unlock( bucket ); } + /* Close bencoded scrape dictionary */ *r++='e'; *r++='e'; + /* Release unused memory in current output buffer */ iovec_fixlast( iovec_entries, iovector, OT_SCRAPE_CHUNK_SIZE - ( re - r ) ); + /* Return answer size */ return iovec_length( iovec_entries, iovector ); }