Improved transport and module code.v0.1.24

1 files changed, 43 insertions, 14 deletions

diff --git a/src/gnunet/service/dht/routingtable.go b/src/gnunet/service/dht/routingtable.go
index 0078b71..2933e6a 100644
--- a/src/gnunet/service/dht/routingtable.go
+++ b/src/gnunet/service/dht/routingtable.go
@@ -101,7 +101,7 @@ type RoutingTable struct {
         ref       *PeerAddress              // reference address for distance
         buckets   []*Bucket                 // list of buckets
         list      map[*PeerAddress]struct{} // keep list of peers
-        rwlock    sync.RWMutex              // lock for write operations
+        mtx       sync.RWMutex              // lock for write operations
         l2nse     float64                   // log2 of estimated network size
         inProcess bool                      // flag if Process() is running
 }
@@ -131,8 +131,8 @@ func NewRoutingTable(ref *PeerAddress) *RoutingTable {
 // Returns true if the entry was added, false otherwise.
 func (rt *RoutingTable) Add(p *PeerAddress) bool {
         // ensure one write and no readers
-        rt.rwlock.Lock()
-        defer rt.rwlock.Unlock()
+        rt.lock(false)
+        defer rt.unlock(false)
 
         // check if peer is already known
         if _, ok := rt.list[p]; ok {
@@ -153,8 +153,8 @@ func (rt *RoutingTable) Add(p *PeerAddress) bool {
 // Returns true if the entry was removed, false otherwise.
 func (rt *RoutingTable) Remove(p *PeerAddress) bool {
         // ensure one write and no readers
-        rt.rwlock.Lock()
-        defer rt.rwlock.Unlock()
+        rt.lock(false)
+        defer rt.unlock(false)
 
         // compute distance (bucket index) and remove entry from bucket
         _, idx := p.Distance(rt.ref)
@@ -170,10 +170,15 @@ func (rt *RoutingTable) Remove(p *PeerAddress) bool {
 //----------------------------------------------------------------------
 
 // Process a function f in the locked context of a routing table
-func (rt *RoutingTable) Process(f func() error) error {
-        // ensure one write and no readers
-        rt.rwlock.Lock()
-        defer rt.rwlock.Unlock()
+func (rt *RoutingTable) Process(f func() error, readonly bool) error {
+        // handle locking
+        rt.lock(readonly)
+        rt.inProcess = true
+        defer func() {
+                rt.inProcess = false
+                rt.unlock(readonly)
+        }()
+        // call function in unlocked context
         return f()
 }
 
@@ -184,8 +189,8 @@ func (rt *RoutingTable) Process(f func() error) error {
 // SelectClosestPeer for a given peer address and bloomfilter.
 func (rt *RoutingTable) SelectClosestPeer(p *PeerAddress, bf *PeerBloomFilter) (n *PeerAddress) {
         // no writer allowed
-        rt.rwlock.RLock()
-        defer rt.rwlock.RUnlock()
+        rt.mtx.RLock()
+        defer rt.mtx.RUnlock()
 
         // find closest address
         var dist *math.Int
@@ -204,8 +209,8 @@ func (rt *RoutingTable) SelectClosestPeer(p *PeerAddress, bf *PeerBloomFilter) (
 // included in the bloomfilter)
 func (rt *RoutingTable) SelectRandomPeer(bf *PeerBloomFilter) *PeerAddress {
         // no writer allowed
-        rt.rwlock.RLock()
-        defer rt.rwlock.RUnlock()
+        rt.mtx.RLock()
+        defer rt.mtx.RUnlock()
 
         // select random entry from list
         if size := len(rt.list); size > 0 {
@@ -279,11 +284,35 @@ func (rt *RoutingTable) heartbeat(ctx context.Context) {
                         }
                 }
                 return nil
-        }); err != nil {
+        }, false); err != nil {
                 logger.Println(logger.ERROR, "[dht] RT heartbeat: "+err.Error())
         }
 }
 
+//----------------------------------------------------------------------
+
+// lock with given mode (if not in processing function)
+func (rt *RoutingTable) lock(readonly bool) {
+        if !rt.inProcess {
+                if readonly {
+                        rt.mtx.RLock()
+                } else {
+                        rt.mtx.Lock()
+                }
+        }
+}
+
+// lock with given mode (if not in processing function)
+func (rt *RoutingTable) unlock(readonly bool) {
+        if !rt.inProcess {
+                if readonly {
+                        rt.mtx.RUnlock()
+                } else {
+                        rt.mtx.Unlock()
+                }
+        }
+}
+
 //======================================================================
 // Routing table buckets
 //======================================================================