Start to opentracker's memory requirements

* peer lists for v4 and v6 are now lazily allocated and, more importantly, will be freed once there are no more peers
* The downloaded count is now per torrent and not per peer list anymore, moving in what was alignment loss, anyway
* The (now) per torrent downloaded and the per peer list peer and seed count shrunk from size_t to uint32_t
* A helper guards accesses to the peer and seed count to prevent null pointer dereferences
* The base time also shrank from time_t to uint32_t, minutes since the epoch currently fits in 25 bits

1 files changed, 9 insertions, 6 deletions

diff --git a/src/trackerlogic.h b/src/trackerlogic.h
index 241b6a7..6b53406 100644
--- a/src/trackerlogic.h
+++ b/src/trackerlogic.h
@@ -165,17 +165,17 @@ struct ot_peerlist;
 typedef struct ot_peerlist ot_peerlist;
 typedef struct {
   ot_hash      hash;
-  ot_peerlist *peer_list6;
-  ot_peerlist *peer_list4;
+  ot_peerlist *peer_list6; /* NULL until the torrent has a v6 peer */
+  ot_peerlist *peer_list4; /* NULL until the torrent has a v4 peer */
+  uint32_t     base;       /* minutes, when the torrent was last cleaned */
+  uint32_t     down_count; /* completed events, summed over both families */
 } ot_torrent;
 
 #include "ot_vector.h"
 
 struct ot_peerlist {
-  ot_time   base;
-  size_t    seed_count;
-  size_t    peer_count;
-  size_t    down_count;
+  uint32_t  seed_count;
+  uint32_t  peer_count;
   /* normal peers vector or
      pointer to ot_vector[32] buckets if data != NULL and space == 0
   */
@@ -183,6 +183,9 @@ struct ot_peerlist {
 };
 #define OT_PEERLIST_HASBUCKETS(peer_list) ((peer_list)->peers.size > (peer_list)->peers.space)
 
+static inline uint32_t peerlist_peer_count(const ot_peerlist *peer_list) { return peer_list ? peer_list->peer_count : 0; }
+static inline uint32_t peerlist_seed_count(const ot_peerlist *peer_list) { return peer_list ? peer_list->seed_count : 0; }
+
 /* The http replies the tracker counts when it has to refuse a request. */
 enum {
   CODE_HTTPERROR_302,