(libT) (1) shave a few bytes from tr_peer and tr_ratecontrol's footprints. (2) remove some dead code.

libtransmission/peer-mgr-private.h

@@ -34,27 +34,6 @@ enum
     ENCRYPTION_PREFERENCE_NO
 };
 
-/**
-*** The "SWIFT" system is described by Karthik Tamilmani,
-*** Vinay Pai, and Alexander Mohr of Stony Brook University
-*** in their paper "SWIFT: A System With Incentives For Trading"
-*** http://citeseer.ist.psu.edu/tamilmani04swift.html
-***
-*** More SWIFT constants are defined in peer-mgr.c
-**/
-
-/**
- * Use SWIFT?
- */
-static const int SWIFT_ENABLED = 0;
-
-/**
- * For every byte the peer uploads to us,
- * allow them to download this many bytes from us
- */
-static const double SWIFT_REPAYMENT_RATIO = 1.33;
-
-
 typedef struct tr_peer
 {
     unsigned int  peerIsChoked : 1;
@@ -88,10 +67,8 @@ typedef struct tr_peer
     struct tr_ratecontrol * rcToClient;
     struct tr_ratecontrol * rcToPeer;
 
-    double rateToClient;
+    float rateToClient;
-    double rateToPeer;
+    float rateToPeer;
-
-    int64_t credit;
 }
 tr_peer;
 

libtransmission/peer-mgr.c

@@ -35,35 +35,6 @@
 #include "trevent.h"
 #include "utils.h"
 
-/**
-*** The "SWIFT" system is described by Karthik Tamilmani,
-*** Vinay Pai, and Alexander Mohr of Stony Brook University
-*** in their paper "SWIFT: A System With Incentives For Trading"
-*** http://citeseer.ist.psu.edu/tamilmani04swift.html
-***
-*** More SWIFT constants are defined in peer-mgr-private.h
-**/
-
-/**
- * Allow new peers to download this many bytes from
- * us when getting started.  This can prevent gridlock
- * with other peers using tit-for-tat algorithms
- */
-static const int SWIFT_INITIAL_CREDIT = 64 * 1024; /* 64 KiB */
-
-/**
- * We expend a fraction of our torrent's total upload speed
- * on largesse by uniformly distributing free credit to
- * all of our peers.  This too helps prevent gridlock.
- */
-static const double SWIFT_LARGESSE = 0.15; /* 15% of our UL */
-
-/**
- * How frequently to extend largesse-based credit
- */
-static const int SWIFT_PERIOD_MSEC = 5000;
-
-
 enum
 {
     /* how frequently to change which peers are choked */
@@ -135,7 +106,6 @@ typedef struct
     tr_timer * reconnectTimer;
     tr_timer * rechokeTimer;
     tr_timer * refillTimer;
-    tr_timer * swiftTimer;
     tr_torrent * tor;
     tr_peer * optimistic; /* the optimistic peer, or NULL if none */
     tr_bitfield * requested;
@@ -308,7 +278,6 @@ peerConstructor( const struct in_addr * in_addr )
 {
     tr_peer * p;
     p = tr_new0( tr_peer, 1 );
-    p->credit = SWIFT_INITIAL_CREDIT;
     p->rcToClient = tr_rcInit( );
     p->rcToPeer = tr_rcInit( );
     memcpy( &p->in_addr, in_addr, sizeof(struct in_addr) );
@@ -392,7 +361,6 @@ torrentDestructor( Torrent * t )
     tr_timerFree( &t->reconnectTimer );
     tr_timerFree( &t->rechokeTimer );
     tr_timerFree( &t->refillTimer );
-    tr_timerFree( &t->swiftTimer );
 
     tr_bitfieldFree( t->requested );
     tr_ptrArrayFree( t->pool, (PtrArrayForeachFunc)tr_free );
@@ -1235,7 +1203,6 @@ tr_peerMgrGetPeers( tr_peerMgr      * manager,
 
 static int reconnectPulse( void * vtorrent );
 static int rechokePulse( void * vtorrent );
-static int swiftPulse( void * vtorrent );
 
 void
 tr_peerMgrStartTorrent( tr_peerMgr     * manager,
@@ -1250,7 +1217,6 @@ tr_peerMgrStartTorrent( tr_peerMgr     * manager,
     assert( t != NULL );
     assert( ( t->isRunning != 0 ) == ( t->reconnectTimer != NULL ) );
     assert( ( t->isRunning != 0 ) == ( t->rechokeTimer != NULL ) );
-    assert( ( t->isRunning != 0 ) == ( t->swiftTimer != NULL ) );
 
     if( !t->isRunning )
     {
@@ -1264,15 +1230,9 @@ tr_peerMgrStartTorrent( tr_peerMgr     * manager,
                                        rechokePulse, t,
                                        RECHOKE_PERIOD_MSEC );
 
-        t->swiftTimer = tr_timerNew( t->manager->handle,
-                                     swiftPulse, t,
-                                     SWIFT_PERIOD_MSEC );
-
         reconnectPulse( t );
 
         rechokePulse( t );
-
-        swiftPulse( t );
     }
 
     managerUnlock( manager );
@@ -1286,7 +1246,6 @@ stopTorrent( Torrent * t )
     t->isRunning = 0;
     tr_timerFree( &t->rechokeTimer );
     tr_timerFree( &t->reconnectTimer );
-    tr_timerFree( &t->swiftTimer );
 
     /* disconnect the peers. */
     tr_ptrArrayForeach( t->peers, (PtrArrayForeachFunc)peerDestructor );
@@ -1563,7 +1522,7 @@ isSame( const tr_peer * peer )
 ***
 **/
 
-static double
+static int
 getWeightedRate( const tr_peer * peer, int clientIsSeed )
 {
     return (int)( 10.0 * ( clientIsSeed ? peer->rateToPeer
@@ -1658,55 +1617,6 @@ rechokePulse( void * vtorrent )
     return TRUE;
 }
 
-/***
-****
-***/
-
-static int
-swiftPulse( void * vtorrent )
-{
-    Torrent * t = vtorrent;
-    torrentLock( t );
-
-    if( !tr_torrentIsSeed( t->tor ) )
-    {
-        int i;
-        int peerCount = 0;
-        int deadbeatCount = 0;
-        tr_peer ** peers = getConnectedPeers( t, &peerCount );
-        tr_peer ** deadbeats = tr_new( tr_peer*, peerCount );
-
-        const double ul_KiBsec = tr_rcRate( t->tor->upload );
-        const double ul_KiB = ul_KiBsec * (SWIFT_PERIOD_MSEC/1000.0);
-        const double ul_bytes = ul_KiB * 1024;
-        const double freeCreditTotal = ul_bytes * SWIFT_LARGESSE;
-        int freeCreditPerPeer;
-
-        for( i=0; i<peerCount; ++i ) {
-            tr_peer * peer = peers[i];
-            if( peer->credit <= 0 )
-                deadbeats[deadbeatCount++] =  peer;
-        }
-
-        freeCreditPerPeer = (int)( freeCreditTotal / deadbeatCount );
-        for( i=0; i<deadbeatCount; ++i )
-            deadbeats[i]->credit = freeCreditPerPeer;
-
-        tordbg( t, "%d deadbeats, "
-            "who are each being granted %d bytes' credit "
-            "for a total of %.1f KiB, "
-            "%d%% of the torrent's ul speed %.1f\n",
-            deadbeatCount, freeCreditPerPeer,
-            ul_KiBsec*SWIFT_LARGESSE, (int)(SWIFT_LARGESSE*100), ul_KiBsec );
-
-        tr_free( deadbeats );
-        tr_free( peers );
-    }
-
-    torrentUnlock( t );
-    return TRUE;
-}
-
 /***
 ****
 ****  Life and Death
@@ -1752,9 +1662,9 @@ shouldPeerBeClosed( const Torrent * t, const tr_peer * peer, int peerCount )
         const int relaxStrictnessIfFewerThanN = (int)((getMaxPeerCount(tor) * 0.9) + 0.5);
         /* if we have >= relaxIfFewerThan, strictness is 100%.
          * if we have zero connections, strictness is 0% */
-        const double strictness = peerCount >= relaxStrictnessIfFewerThanN
+        const float strictness = peerCount >= relaxStrictnessIfFewerThanN
             ? 1.0
-            : peerCount / (double)relaxStrictnessIfFewerThanN;
+            : peerCount / (float)relaxStrictnessIfFewerThanN;
         const int lo = MIN_UPLOAD_IDLE_SECS;
         const int hi = MAX_UPLOAD_IDLE_SECS;
         const int limit = lo + ((hi-lo) * strictness);

libtransmission/peer-msgs.c

@@ -1160,7 +1160,6 @@ clientGotBytes( tr_peermsgs * msgs, uint32_t byteCount )
     tor->activityDate = now;
     tor->downloadedCur += byteCount;
     msgs->info->pieceDataActivityDate = now;
-    msgs->info->credit += (int)(byteCount * SWIFT_REPAYMENT_RATIO);
     tr_rcTransferred( msgs->info->rcToClient, byteCount );
     tr_rcTransferred( tor->download, byteCount );
     tr_rcTransferred( tor->handle->download, byteCount );
@@ -1383,7 +1382,6 @@ peerGotBytes( tr_peermsgs * msgs, uint32_t byteCount )
     tor->activityDate = now;
     tor->uploadedCur += byteCount;
     msgs->info->pieceDataActivityDate = now;
-    msgs->info->credit -= byteCount;
     tr_rcTransferred( msgs->info->rcToPeer, byteCount );
     tr_rcTransferred( tor->upload, byteCount );
     tr_rcTransferred( tor->handle->upload, byteCount );
@@ -1578,27 +1576,13 @@ sendKeepalive( tr_peermsgs * msgs )
 ***
 **/
 
-static int
-isSwiftEnabled( const tr_peermsgs * msgs )
-{
-    /* rationale: SWIFT is good for getting rid of deadbeats, but most
-     * private trackers have ratios where you _want_ to feed deadbeats
-     * as much as possible.  So we disable SWIFT on private torrents */
-    return SWIFT_ENABLED
-        && !tr_torrentIsSeed( msgs->torrent )
-        && !tr_torrentIsPrivate( msgs->torrent );
-}
-
 static size_t
 getUploadMax( const tr_peermsgs * msgs )
 {
     static const size_t maxval = ~0;
     const tr_torrent * tor = msgs->torrent;
-    const int useSwift = isSwiftEnabled( msgs );
-    const size_t swiftLeft = msgs->info->credit;
     int speedLeft;
     int bufLeft;
-    size_t ret;
 
     if( tor->uploadLimitMode == TR_SPEEDLIMIT_GLOBAL )
         speedLeft = tor->handle->useUploadLimit ? tr_rcBytesLeft( tor->handle->upload ) : maxval;
@@ -1611,10 +1595,7 @@ getUploadMax( const tr_peermsgs * msgs )
      * queued up in it... blocksize, +13 for the size of the BT protocol's
      * block message overhead */
     bufLeft = tor->blockSize + 13 - tr_peerIoWriteBytesWaiting( msgs->io );
-    ret = MIN( speedLeft, bufLeft );
+    return MIN( speedLeft, bufLeft );
-    if( useSwift)
-        ret = MIN( ret, swiftLeft );
-    return ret;
 }
 
 static int

libtransmission/ratecontrol.c

@@ -42,8 +42,8 @@ struct tr_transfer
 
 struct tr_ratecontrol
 {
-    int limit;
+    int8_t limit;
-    int newest;
+    int8_t newest;
     struct tr_transfer transfers[HISTORY_SIZE];
 };
 

libtransmission/transmission.h

@@ -52,6 +52,20 @@ typedef uint32_t tr_file_index_t;
 typedef uint32_t tr_piece_index_t;
 typedef uint64_t tr_block_index_t;
 
+/**
+ * @brief returns Transmission's default configuration file directory.
+ *
+ * The default configuration directory is determined this way:
+ * - If the TRANSMISSION_HOME environmental variable is set,
+ *   its value is returned.
+ * - otherwise, if we're running on Darwin,
+ *   "$HOME/Library/Application Support/Transmission" is returned.
+ * - otherwise, if we're running on WIN32,
+ *   "$CSIDL_APPDATA/Transmission" is returned.
+ * - otherwise, if XDG_CONFIG_HOME is set,
+ *   "$XDG_CONFIG_HOME/transmission" is returned.
+ * - lastly, $HOME/.config/transmission" is used.
+ */
 const char* tr_getDefaultConfigDir( void );
 
 typedef struct tr_ctor tr_ctor;
@@ -72,61 +86,123 @@ typedef struct tr_torrent tr_torrent;
  * @{
  */
 
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_CONFIG_DIR                  tr_getDefaultConfigDir()
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_PEX_ENABLED                 1
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_PORT_FORWARDING_ENABLED     0
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_PORT                        51413
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_GLOBAL_PEER_LIMIT           200
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_PEER_SOCKET_TOS             8
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_BLOCKLIST_ENABLED           0
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_RPC_ENABLED                 0
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_RPC_PORT                    9091
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_RPC_PORT_STR                "9091"
+/** @see tr_sessionInitFull */
 #define TR_DEFAULT_RPC_ACL                     "+127.0.0.1"
 
 /**
- * Create and return a Transmission session handle.
+ * @brief Start a libtransmission session.
+ * @return an opaque handle to the new session
  *
- * @param configDir the config directory where libtransmission config
+ * @param configDir
- *                  subdirectories will be found, such as "torrents",
+ *  The config directory where libtransmission config subdirectories
- *                  "resume", and "blocklists".
+ *  will be found, such as "torrents", "resume", and "blocklists".
- *                  TR_DEFAULT_CONFIG_DIR can be used as a default.
+ *  #TR_DEFAULT_CONFIG_DIR can be used as a default.
- * @param downloadDir The default directory to save added torrents.
+ *
- *                    This can be changed per-session with
+ * @param downloadDir
- *                    tr_sessionSetDownloadDir() and per-torrent with
+ *  The default directory to save added torrents.
- *                    tr_ctorSetDownloadDir().
+ *  This can be changed per-session with
- * @param tag   Obsolete.  Only used now for locating legacy fastresume files.
+ *  tr_sessionSetDownloadDir() and per-torrent with
- *              Valid tags: beos, cli, daemon, gtk, macos, wx
+ *  tr_ctorSetDownloadDir().
- * @param isPexEnabled whether or not PEX is allowed for non-private torrents.
+ *
- *                     This can be changed per-session with
+ * @param tag
- *                     tr_sessionSetPexEnabled().
+ *  Obsolete.  Only used now for locating legacy fastresume files.
- *                     TR_DEFAULT_PEX_ENABLED is the default.
+ *  This will be removed at some point in the future.
- * @param isPortForwardingEnabled If true, libtransmission will attempt
+ *  Valid tags: beos cli daemon gtk macos wx
- *                       to find a local UPnP-enabled or NATPMP-enabled
+ *
- *                       router and forward a port from there to the local
+ * @param isPexEnabled
- *                       machine.  This is so remote peers can initiate
+ *  whether or not PEX is allowed for non-private torrents.
- *                       connections with us.
+ *  This can be changed per-session with
- *                       TR_DEFAULT_PORT_FORWARDING_ENABLED is the default.
+ *  tr_sessionSetPexEnabled().
- * @param publicPort Port number to open for incoming peer connections.
+ *  #TR_DEFAULT_PEX_ENABLED is the default.
- *                   TR_DEFAULT_PORT is the default.
+ *
- * @param encryptionMode must be one of TR_PLAINTEXT_PREFERRED,
+ * @param isPortForwardingEnabled
- *                       TR_ENCRYPTION_PREFERRED, or TR_ENCRYPTION_REQUIRED.
+ *  If true, libtransmission will attempt
- * @param isUploadLimitEnabled If true, libtransmission will limit the entire
+ *  to find a local UPnP-enabled or NATPMP-enabled
- *                             session's upload speed from `uploadLimit'.
+ *  router and forward a port from there to the local
- * @param uploadLimit The speed limit to use for the entire session when
+ *  machine.  This is so remote peers can initiate
- *                    isUploadLimitEnabled is true.
+ *  connections with us.
- * @param isDownloadLimitEnabled If true, libtransmission will limit the entire
+ *  #TR_DEFAULT_PORT_FORWARDING_ENABLED is the default.
- *                               session's download speed from `downloadLimit'.
+ *
- * @param downloadLimit The speed limit to use for the entire session when
+ * @param publicPort
- *                      isDownloadLimitEnabled is true.
+ *  Port number to open for incoming peer connections.
- * @param peerLimit The maximum number of peer connections allowed in a session.
+ *  #TR_DEFAULT_PORT is the default.
- *                  TR_DEFAULT_GLOBAL_PEER_LIMIT can be used as a default.
+ *
+ * @param encryptionMode
+ *  Must be one of #TR_PLAINTEXT_PREFERRED,
+ *  #TR_ENCRYPTION_PREFERRED, or #TR_ENCRYPTION_REQUIRED.
+ *
+ * @param isUploadLimitEnabled
+ *  If true, libtransmission will limit the entire
+ *  session's upload speed from "uploadLimit".
+ *
+ * @param uploadLimit
+ *  The speed limit to use for the entire session when
+ *  "isUploadLimitEnabled" is true.
+ *
+ * @param isDownloadLimitEnabled
+ *  If true, libtransmission will limit the entire
+ *  session's download speed from "downloadLimit".
+ *
+ * @param downloadLimit
+ *  The speed limit to use for the entire session when
+ *  "isDownloadLimitEnabled" is true.
+ *
+ * @param peerLimit
+ *  The maximum number of peer connections allowed in a session.
+ *  #TR_DEFAULT_GLOBAL_PEER_LIMIT can be used as a default.
+ *
+ * @param messageLevel
+ *  Verbosity level of libtransmission's logging mechanism.
+ *  Must be one of #TR_MSG_ERR, #TR_MSG_INF, #TR_MSG_DBG.
+ * 
+ * @param isMessageQueueingEnabled
+ *  If true, then messages will build up in a queue until
+ *  processed by the client application.
+ *
+ * @param isBlocklistEnabled
+ *  If true, then Transmission will not allow peer connections
+ *  to the IP addressess specified in the blocklist.
+ * 
+ * @param peerSocketTOS
+ *
+ * @param rpcIsEnabled
+ *  If true, then libtransmission will open an http server port
+ *  to listen for incoming RPC requests.
+ *
+ * @param rpcPort
+ *  The port on which to listen for incoming RPC requests
+ *
+ * @param rpcACL
+ *  The access control list for allowing/denying RPC requests
+ *  from specific IP ranges.
+ *  @see tr_sessionSetRPCACL()
  *
  * @see TR_DEFAULT_PEER_SOCKET_TOS
  * @see TR_DEFAULT_BLOCKLIST_ENABLED
  * @see TR_DEFAULT_RPC_ENABLED
  * @see TR_DEFAULT_RPC_PORT
  * @see TR_DEFAULT_RPC_ACL
+ * @see tr_sessionClose()
  */
 tr_handle * tr_sessionInitFull( const char * configDir,
                                 const char * downloadDir,
@@ -146,17 +222,20 @@ tr_handle * tr_sessionInitFull( const char * configDir,
                                 int          peerSocketTOS,
                                 int          rpcIsEnabled,
                                 int          rpcPort,
-                                const char * rpcACL );
+                                const char * rpcAccessControlList );
 
 /**
- * Like tr_sessionInitFull() but with default values supplied.
+ * @brief shorter form of tr_sessionInitFull()
+ *
+ * @deprecated Use tr_sessionInitFull() instead.
  */ 
 tr_handle * tr_sessionInit( const char * configDir,
                             const char * downloadDir,
                             const char * tag );
 
 /**
- * Shut down a libtransmission instance created by tr_sessionInit*()
+ * @brief end a libtransmission session
+ * @see tr_sessionInitFull()
  */
 void tr_sessionClose( tr_handle * );
 
@@ -170,18 +249,43 @@ const char * tr_sessionGetConfigDir( const tr_handle * );
 /**
  * Set the per-session default download folder for new torrents.
  * @see tr_sessionInitFull()
+ * @see tr_sessionGetDownloadDir()
  * @see tr_ctorSetDownloadDir()
  */
 void tr_sessionSetDownloadDir( tr_handle *, const char * downloadDir );
 
+/**
+ * Get the default download folder for new torrents.
+ *
+ * This is set by tr_sessionInitFull() or tr_sessionSetDownloadDir(),
+ * and can be overridden on a per-torrent basis by tr_ctorSetDownloadDir().
+ */
 const char * tr_sessionGetDownloadDir( const tr_handle * );
 
+/**
+ * @brief Set whether or not RPC calls are allowed in this session.
+ *
+ * @details If true, libtransmission will open a server socket to listen 
+ * for incoming http RPC requests as described in docs/rpc-spec.txt.
+ *
+ * This is intially set by tr_sessionInitFull() and can be
+ * queried by tr_sessionIsRPCEnabled().
+ */
 void tr_sessionSetRPCEnabled( tr_handle *, int isEnabled );
 
+/** @brief Get whether or not RPC calls are allowed in this session.
+    @see tr_sessionInitFull()
+    @see tr_sessionSetRPCEnabled() */
 int tr_sessionIsRPCEnabled( const tr_handle * handle );
 
+/** @brief Specify which port to listen for RPC requests on.
+    @see tr_sessionInitFull()
+    @see tr_sessionGetRPCPort */
 void tr_sessionSetRPCPort( tr_handle *, int port );
 
+/** @brief Get which port to listen for RPC requests on.
+    @see tr_sessionInitFull()
+    @see tr_sessionSetRPCPort */
 int tr_sessionGetRPCPort( const tr_handle * );
 
 /**
@@ -197,9 +301,15 @@ int tr_sessionGetRPCPort( const tr_handle * );
  * Client applications need to validate user input, or better yet
  * generate it from a higher-level interface that doesn't allow user error,
  * before calling this function.
+ *
+ * @see tr_sessionInitFull
+ * @see tr_sessionGetRPCACL
  */
 void tr_sessionSetRPCACL( tr_handle *, const char * acl );
 
+/** Returns the Access Control List for allowing/denying RPC requests.
+    @see tr_sessionInitFull
+    @see tr_sessionSetRPCACL */
 const char* tr_sessionGetRPCACL( const tr_handle * );
 
 typedef enum
@@ -231,9 +341,9 @@ void tr_sessionSetRPCCallback( tr_handle    * handle,
 
 typedef struct tr_session_stats
 {
+    float ratio;              /* TR_RATIO_INF, TR_RATIO_NA, or total up/down */
     uint64_t uploadedBytes;   /* total up */
     uint64_t downloadedBytes; /* total down */
-    double ratio;             /* TR_RATIO_INF, TR_RATIO_NA, or total up/down */
     uint64_t filesAdded;      /* number of files added */
     uint64_t sessionCount;    /* program started N times */
     uint64_t secondsActive;   /* how long Transmisson's been running */