You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
opentracker/ot_fullscrape.c

100 lines
3.2 KiB
C

/* This software was written by Dirk Engling <erdgeist@erdgeist.org>
It is considered beerware. Prost. Skol. Cheers or whatever. */
/* System */
#include <sys/uio.h>
#include <stdio.h>
#include <string.h>
/* Libowfat */
/* Opentracker */
#include "trackerlogic.h"
#include "ot_mutex.h"
#include "ot_iovec.h"
#include "ot_fullscrape.h"
/* Fetch full scrape info for all torrents
Full scrapes usually are huge and one does not want to
allocate more memory. So lets get them in 1M units
*/
#define OT_SCRAPE_CHUNK_SIZE (256*1024)
/* "d8:completei%zde10:downloadedi%zde10:incompletei%zdee" */
#define OT_FULLSCRAPE_MAXENTRYLEN 100
size_t return_fullscrape_for_tracker( int *iovec_entries, struct iovec **iovector ) {
int bucket;
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; bucket<OT_BUCKET_COUNT; ++bucket ) {
/* Get exclusive access to that bucket */
ot_vector *torrents_list = mutex_bucket_lock( bucket );
size_t tor_offset;
/* For each torrent in this bucket.. */
for( tor_offset=0; tor_offset<torrents_list->size; ++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 );
}