even more TCP fixage.

- don't try to remove spawned sockets from Endpoints hashtable.
 - return B_WOULD_BLOCK (EAGAIN) when we time out in acquire_sem().
 - use B_RELEASE_IF_WAITING_ONLY in the TCP WaitList.
 - fixed a off by one issue in ReadData() which could result in more than needed iterations (and waiting).
 - implemented prepending new buffers to a net_buffer.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@20639 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/add-ons/kernel/network/protocols/tcp/EndpointManager.cpp

@@ -319,6 +319,7 @@ EndpointManager::Unbind(TCPEndpoint *endpoint)
 
 	RecursiveLocker locker(&fLock);
 
+	if (!endpoint->fSpawned) {
 		TCPEndpoint *other = _LookupEndpoint(gAddressModule->get_port(
 			(sockaddr *)&endpoint->socket->address));
 		if (other != endpoint) {
@@ -339,6 +340,7 @@ EndpointManager::Unbind(TCPEndpoint *endpoint)
 			if (other != NULL)
 				hash_insert(fEndpointHash, other);
 		}
+	}
 
 	endpoint->fEndpointNextWithSamePort = NULL;
 	_RemoveConnection(endpoint);

src/add-ons/kernel/network/protocols/tcp/TCPEndpoint.cpp

@@ -49,8 +49,9 @@
 //#define TRACE_TCP
 
 #ifdef TRACE_TCP
-// the space after 'this' is important in order for this to work with cpp 2.95
-#	define TRACE(format, args...)	dprintf("TCP:%p:" format "\n", this , ##args)
+// the space before ', ##args' is important in order for this to work with cpp 2.95
+#	define TRACE(format, args...)	dprintf("TCP [%llu] %p (%12s) " format "\n", \
+		system_time(), this, name_for_state(fState) , ##args)
 #else
 #	define TRACE(args...)			do { } while (0)
 #endif
@@ -79,8 +80,17 @@ absolute_timeout(bigtime_t timeout)
 }
 
 
+static inline status_t
+posix_error(status_t error)
+{
+	if (error == B_TIMED_OUT)
+		return B_WOULD_BLOCK;
+
+	return error;
+}
+
+
 WaitList::WaitList(const char *name)
-	: fWaiting(0)
 {
 	fSem = create_sem(0, name);
 }
@@ -100,15 +110,13 @@ WaitList::InitCheck() const
 
 
 status_t
-WaitList::Wait(RecursiveLocker &locker, bigtime_t timeout)
+WaitList::Wait(RecursiveLocker &locker, bigtime_t timeout, bool wakeNext)
 {
-	// this function is called with `locker' held.
-	fWaiting++;
 	locker.Unlock();
-	status_t status = acquire_sem_etc(fSem, 1, B_ABSOLUTE_TIMEOUT |
-		B_CAN_INTERRUPT, timeout);
+	status_t status = acquire_sem_etc(fSem, 1, B_ABSOLUTE_TIMEOUT
+		| B_CAN_INTERRUPT, timeout);
 	locker.Lock();
-	if (status == B_OK)
+	if (wakeNext && status == B_OK)
 		Signal();
 	return status;
 }
@@ -117,14 +125,8 @@ WaitList::Wait(RecursiveLocker &locker, bigtime_t timeout)
 void
 WaitList::Signal()
 {
-	// the same locker used with Wait() must be held
-	// when calling this function.
-
-	if (fWaiting == 0)
-		return;
-
-	fWaiting--;
-	release_sem_etc(fSem, 1, B_DO_NOT_RESCHEDULE);
+	release_sem_etc(fSem, 1, B_DO_NOT_RESCHEDULE
+		| B_RELEASE_IF_WAITING_ONLY);
 }
 
 
@@ -152,7 +154,8 @@ TCPEndpoint::TCPEndpoint(net_socket *socket)
 	fRoundTripTime(TCP_INITIAL_RTT),
 	fState(CLOSED),
 	fFlags(0), //FLAG_OPTION_WINDOW_SHIFT),
-	fError(B_OK)
+	fError(B_OK),
+	fSpawned(false)
 {
 	//gStackModule->init_timer(&fTimer, _TimeWait, this);
 
@@ -228,7 +231,7 @@ TCPEndpoint::Close()
 	if (status != B_OK)
 		return status;
 
-	TRACE("Close(): Entering state %s", name_for_state(fState));
+	TRACE("Close() after Shutdown()");
 
 	if (socket->options & SO_LINGER) {
 		TRACE("Close(): Lingering for %i secs", socket->linger);
@@ -277,13 +280,8 @@ TCPEndpoint::Connect(const struct sockaddr *address)
 	TRACE("Connect() on address %s",
 		  AddressString(gDomain, address, true).Data());
 
-	if (address->sa_family != AF_INET)
-		return EAFNOSUPPORT;
-
 	RecursiveLocker locker(&fLock);
 
-	TRACE("  Connect(): in state %s", name_for_state(fState));
-
 	// Can only call connect() from CLOSED or LISTEN states
 	// otherwise endpoint is considered already connected
 	if (fState == LISTEN) {
@@ -355,7 +353,7 @@ TCPEndpoint::Connect(const struct sockaddr *address)
 
 	TRACE("  Connect(): Connection complete: %s", strerror(status));
 
-	return status;
+	return posix_error(status);
 }
 
 
@@ -506,7 +504,7 @@ TCPEndpoint::SendData(net_buffer *buffer)
 		while (fSendQueue.Free() < chunk->size) {
 			status_t status = fSendList.Wait(lock, timeout);
 			if (status < B_OK)
-				return status;
+				return posix_error(status);
 		}
 
 		// TODO: check state!
@@ -569,7 +567,7 @@ TCPEndpoint::ReadData(size_t numBytes, uint32 flags, net_buffer** _buffer)
 			// we need to wait until the connection becomes established
 			status_t status = fSendList.Wait(locker, timeout);
 			if (status < B_OK)
-				return status;
+				return posix_error(status);
 		}
 	}
 
@@ -589,8 +587,8 @@ TCPEndpoint::ReadData(size_t numBytes, uint32 flags, net_buffer** _buffer)
 			return B_OK;
 		}
 
-		if (fReceiveQueue.Available() > dataNeeded ||
-				(fReceiveQueue.PushedData() > 0
+		if (fReceiveQueue.Available() >= dataNeeded ||
+				((fReceiveQueue.PushedData() > 0)
 					&& (fReceiveQueue.PushedData() >= fReceiveQueue.Available())))
 			break;
 
@@ -603,7 +601,7 @@ TCPEndpoint::ReadData(size_t numBytes, uint32 flags, net_buffer** _buffer)
 		if (flags & MSG_DONTWAIT)
 			return B_WOULD_BLOCK;
 
-		status_t status = fReceiveList.Wait(locker, timeout);
+		status_t status = fReceiveList.Wait(locker, timeout, false);
 		if (status < B_OK) {
 			// The Open Group base specification mentions that EINTR should be
 			// returned if the recv() is interrupted before _any data_ is
@@ -613,7 +611,7 @@ TCPEndpoint::ReadData(size_t numBytes, uint32 flags, net_buffer** _buffer)
 					&& fReceiveQueue.Available() > 0)
 				break;
 
-			return status;
+			return posix_error(status);
 		}
 	}
 
@@ -707,8 +705,8 @@ TCPEndpoint::UpdateTimeWait()
 int32
 TCPEndpoint::ListenReceive(tcp_segment_header &segment, net_buffer *buffer)
 {
-	TRACE("ListenReceive(): Connection in state %s received packet %p (%lu bytes) with flags 0x%x, seq %lu, ack %lu!",
-		  name_for_state(fState), buffer, buffer->size, segment.flags, segment.sequence, segment.acknowledge);
+	TRACE("ListenReceive(): packet %p (%lu bytes) with flags 0x%x, seq %lu, ack %lu!",
+		  buffer, buffer->size, segment.flags, segment.sequence, segment.acknowledge);
 
 	// Essentially, we accept only TCP_FLAG_SYNCHRONIZE in this state,
 	// but the error behaviour differs
@@ -733,6 +731,8 @@ TCPEndpoint::ListenReceive(tcp_segment_header &segment, net_buffer *buffer)
 
 	TCPEndpoint *endpoint = (TCPEndpoint *)newSocket->first_protocol;
 
+	endpoint->fSpawned = true;
+
 	// TODO: proper error handling!
 
 	endpoint->fRoute = gDatalinkModule->get_route(gDomain,
@@ -796,6 +796,9 @@ TCPEndpoint::ListenReceive(tcp_segment_header &segment, net_buffer *buffer)
 int32
 TCPEndpoint::SynchronizeSentReceive(tcp_segment_header &segment, net_buffer *buffer)
 {
+	TRACE("SynchronizeReceive(): packet %p (%lu bytes) with flags 0x%x, seq %lu, ack %lu!",
+		buffer, buffer->size, segment.flags, segment.sequence, segment.acknowledge);
+
 	if ((segment.flags & TCP_FLAG_ACKNOWLEDGE) != 0
 		&& (fInitialSendSequence >= segment.acknowledge
 			|| fSendMax < segment.acknowledge))
@@ -855,8 +858,8 @@ TCPEndpoint::SynchronizeSentReceive(tcp_segment_header &segment, net_buffer *buf
 int32
 TCPEndpoint::Receive(tcp_segment_header &segment, net_buffer *buffer)
 {
-	TRACE("Receive(): Connection in state %s received packet %p (%lu bytes) with flags 0x%x, seq %lu, ack %lu!",
-		  name_for_state(fState), buffer, buffer->size, segment.flags, segment.sequence, segment.acknowledge);
+	TRACE("Receive(): packet %p (%lu bytes) with flags 0x%x, seq %lu, ack %lu!",
+		buffer, buffer->size, segment.flags, segment.sequence, segment.acknowledge);
 
 	// TODO: rethink locking!
 
@@ -1146,7 +1149,7 @@ TCPEndpoint::Receive(tcp_segment_header &segment, net_buffer *buffer)
 	if (buffer->size > 0 || (segment.flags & TCP_FLAG_SYNCHRONIZE) != 0)
 		action |= ACKNOWLEDGE;
 
-	TRACE("Receive():Entering state %s, segment action %ld", name_for_state(fState), action);
+	TRACE("Receive() Action %ld", action);
 
 	return action;
 }

src/add-ons/kernel/network/protocols/tcp/TCPEndpoint.h

@@ -30,12 +30,11 @@ public:
 
 	status_t InitCheck() const;
 
-	status_t Wait(RecursiveLocker &, bigtime_t timeout);
+	status_t Wait(RecursiveLocker &, bigtime_t timeout, bool wakeNext = true);
 	void Signal();
 
 private:
 	sem_id fSem;
-	int32 fWaiting;
 };
 
 
@@ -143,6 +142,8 @@ class TCPEndpoint : public net_protocol {
 		uint32			fFlags;
 		status_t		fError;
 
+		bool			fSpawned;
+
 		// timer
 		net_timer		fRetransmitTimer;
 		net_timer		fPersistTimer;

src/add-ons/kernel/network/stack/net_buffer.cpp

@@ -632,13 +632,47 @@ prepend_size(net_buffer *_buffer, size_t size, void **_contiguousBuffer)
 	if (node->header_space < size) {
 		// we need to prepend a new buffer
 
-		// TODO: implement me!
-		panic("prepending buffer not implemented\n");
+		size_t bytesLeft = size;
+		do {
+			if (node->header_space == 0) {
+				size_t headerSpace = BUFFER_SIZE - sizeof(data_header);
+				// no more space, need another data node
+				data_header *header = create_data_header(headerSpace);
+				if (header == NULL) {
+					// TODO: free up headers we already allocated!
+					return B_NO_MEMORY;
+				}
+
+				data_node *previous = node;
+				node = (data_node *)add_data_node(header);
+
+				init_data_node(node, headerSpace);
+				node->header_space = header->data_space;
+				header->first_node = node;
+
+				list_insert_item_before(&buffer->buffers, previous, node);
+			} else {
+				size_t willConsume = min_c(size, node->header_space);
+
+				node->header_space -= willConsume;
+				node->start -= willConsume;
+				node->used += willConsume;
+				bytesLeft -= willConsume;
+			}
+		} while (bytesLeft > 0);
+
+		size_t offset = 0;
+		for (node = (data_node *)list_get_first_item(&buffer->buffers);
+				node != NULL; node = (data_node *)
+					list_get_next_item(&buffer->buffers, node)) {
+			node->offset = offset;
+			offset += node->used;
+		}
 
 		if (_contiguousBuffer)
 			*_contiguousBuffer = NULL;
 
-		return B_ERROR;
+		return B_OK;
 	}
 
 	// the data fits into this buffer