diff --git a/libfreerdp/core/fastpath.c b/libfreerdp/core/fastpath.c
index 7a43c6c6a..b6c012401 100644
--- a/libfreerdp/core/fastpath.c
+++ b/libfreerdp/core/fastpath.c
@@ -506,7 +506,7 @@ static BOOL fastpath_recv_input_event(rdpFastPath* fastpath, STREAM* s)
 	return TRUE;
 }
 
-BOOL fastpath_recv_inputs(rdpFastPath* fastpath, STREAM* s)
+int fastpath_recv_inputs(rdpFastPath* fastpath, STREAM* s)
 {
 	BYTE i;
 
@@ -518,7 +518,7 @@ BOOL fastpath_recv_inputs(rdpFastPath* fastpath, STREAM* s)
 		 */
 
 		if (stream_get_left(s) < 1)
-			return FALSE;
+			return -1;
 
 		stream_read_BYTE(s, fastpath->numberEvents); /* eventHeader (1 byte) */
 	}
@@ -526,10 +526,10 @@ BOOL fastpath_recv_inputs(rdpFastPath* fastpath, STREAM* s)
 	for (i = 0; i < fastpath->numberEvents; i++)
 	{
 		if (!fastpath_recv_input_event(fastpath, s))
-			return FALSE;
+			return -1;
 	}
 
-	return TRUE;
+	return 0;
 }
 
 static UINT32 fastpath_get_sec_bytes(rdpRdp* rdp)
diff --git a/libfreerdp/core/nego.c b/libfreerdp/core/nego.c
index 07c6ea035..770c6da8c 100644
--- a/libfreerdp/core/nego.c
+++ b/libfreerdp/core/nego.c
@@ -465,9 +465,9 @@ BOOL nego_recv_response(rdpNego* nego)
 	STREAM* s = transport_recv_stream_init(nego->transport, 1024);
 
 	if (transport_read(nego->transport, s) < 0)
-		return FALSE;
+		return -1;
 
-	return nego_recv(nego->transport, s, nego);
+	return ((nego_recv(nego->transport, s, nego) < 0) ? FALSE : TRUE);
 }
 
 /**
@@ -478,7 +478,7 @@ BOOL nego_recv_response(rdpNego* nego)
  * @param extra nego pointer
  */
 
-BOOL nego_recv(rdpTransport* transport, STREAM* s, void* extra)
+int nego_recv(rdpTransport* transport, STREAM* s, void* extra)
 {
 	BYTE li;
 	BYTE type;
@@ -488,7 +488,7 @@ BOOL nego_recv(rdpTransport* transport, STREAM* s, void* extra)
 	length = tpkt_read_header(s);
 
 	if (length == 0)
-		return FALSE;
+		return -1;
 
 	li = tpdu_read_connection_confirm(s);
 
@@ -546,7 +546,7 @@ BOOL nego_recv(rdpTransport* transport, STREAM* s, void* extra)
 		nego->state = NEGO_STATE_FAIL;
 	}
 
-	return TRUE;
+	return 0;
 }
 
 /**
diff --git a/libfreerdp/core/nego.h b/libfreerdp/core/nego.h
index 5b9c31079..622f8f33b 100644
--- a/libfreerdp/core/nego.h
+++ b/libfreerdp/core/nego.h
@@ -117,7 +117,7 @@ void nego_attempt_tls(rdpNego* nego);
 void nego_attempt_rdp(rdpNego* nego);
 
 void nego_send(rdpNego* nego);
-BOOL nego_recv(rdpTransport* transport, STREAM* s, void* extra);
+int nego_recv(rdpTransport* transport, STREAM* s, void* extra);
 BOOL nego_recv_response(rdpNego* nego);
 BOOL nego_read_request(rdpNego* nego, STREAM* s);
 
diff --git a/libfreerdp/core/peer.c b/libfreerdp/core/peer.c
index 059de8cf9..215bcb9c3 100644
--- a/libfreerdp/core/peer.c
+++ b/libfreerdp/core/peer.c
@@ -156,7 +156,7 @@ static BOOL peer_recv_data_pdu(freerdp_peer* client, STREAM* s)
 	return TRUE;
 }
 
-static BOOL peer_recv_tpkt_pdu(freerdp_peer* client, STREAM* s)
+static int peer_recv_tpkt_pdu(freerdp_peer* client, STREAM* s)
 {
 	rdpRdp* rdp;
 	UINT16 length;
@@ -171,7 +171,7 @@ static BOOL peer_recv_tpkt_pdu(freerdp_peer* client, STREAM* s)
 	if (!rdp_read_header(rdp, s, &length, &channelId))
 	{
 		printf("Incorrect RDP header.\n");
-		return FALSE;
+		return -1;
 	}
 
 	if (rdp->settings->DisableEncryption)
@@ -183,7 +183,7 @@ static BOOL peer_recv_tpkt_pdu(freerdp_peer* client, STREAM* s)
 			if (!rdp_decrypt(rdp, s, length - 4, securityFlags))
 			{
 				printf("rdp_decrypt failed\n");
-				return FALSE;
+				return -1;
 			}
 		}
 	}
@@ -195,7 +195,7 @@ static BOOL peer_recv_tpkt_pdu(freerdp_peer* client, STREAM* s)
 	else
 	{
 		if (!rdp_read_share_control_header(s, &pduLength, &pduType, &pduSource))
-			return FALSE;
+			return -1;
 
 		client->settings->PduSource = pduSource;
 
@@ -203,19 +203,19 @@ static BOOL peer_recv_tpkt_pdu(freerdp_peer* client, STREAM* s)
 		{
 			case PDU_TYPE_DATA:
 				if (!peer_recv_data_pdu(client, s))
-					return FALSE;
+					return -1;
 				break;
 
 			default:
 				printf("Client sent pduType %d\n", pduType);
-				return FALSE;
+				return -1;
 		}
 	}
 
-	return TRUE;
+	return 0;
 }
 
-static BOOL peer_recv_fastpath_pdu(freerdp_peer* client, STREAM* s)
+static int peer_recv_fastpath_pdu(freerdp_peer* client, STREAM* s)
 {
 	rdpRdp* rdp;
 	UINT16 length;
@@ -225,10 +225,10 @@ static BOOL peer_recv_fastpath_pdu(freerdp_peer* client, STREAM* s)
 	fastpath = rdp->fastpath;
 	length = fastpath_read_header_rdp(fastpath, s);
 
-	if (length == 0 || length > stream_get_left(s))
+	if ((length == 0) || (length > stream_get_left(s)))
 	{
 		printf("incorrect FastPath PDU header length %d\n", length);
-		return FALSE;
+		return -1;
 	}
 
 	if (fastpath->encryptionFlags & FASTPATH_OUTPUT_ENCRYPTED)
@@ -239,7 +239,7 @@ static BOOL peer_recv_fastpath_pdu(freerdp_peer* client, STREAM* s)
 	return fastpath_recv_inputs(fastpath, s);
 }
 
-static BOOL peer_recv_pdu(freerdp_peer* client, STREAM* s)
+static int peer_recv_pdu(freerdp_peer* client, STREAM* s)
 {
 	if (tpkt_verify_header(s))
 		return peer_recv_tpkt_pdu(client, s);
@@ -256,7 +256,7 @@ static BOOL peer_recv_callback(rdpTransport* transport, STREAM* s, void* extra)
 	{
 		case CONNECTION_STATE_INITIAL:
 			if (!rdp_server_accept_nego(rdp, s))
-				return FALSE;
+				return -1;
 
 			if (rdp->nego->selected_protocol & PROTOCOL_NLA)
 			{
@@ -273,29 +273,29 @@ static BOOL peer_recv_callback(rdpTransport* transport, STREAM* s, void* extra)
 
 		case CONNECTION_STATE_NEGO:
 			if (!rdp_server_accept_mcs_connect_initial(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_MCS_CONNECT:
 			if (!rdp_server_accept_mcs_erect_domain_request(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_MCS_ERECT_DOMAIN:
 			if (!rdp_server_accept_mcs_attach_user_request(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_MCS_ATTACH_USER:
 			if (!rdp_server_accept_mcs_channel_join_request(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_MCS_CHANNEL_JOIN:
 			if (rdp->settings->DisableEncryption)
 			{
 				if (!rdp_server_accept_client_keys(rdp, s))
-					return FALSE;
+					return -1;
 				break;
 			}
 			rdp->state = CONNECTION_STATE_ESTABLISH_KEYS;
@@ -303,12 +303,12 @@ static BOOL peer_recv_callback(rdpTransport* transport, STREAM* s, void* extra)
 
 		case CONNECTION_STATE_ESTABLISH_KEYS:
 			if (!rdp_server_accept_client_info(rdp, s))
-				return FALSE;
+				return -1;
 
 			IFCALL(client->Capabilities, client);
 
 			if (!rdp_send_demand_active(rdp))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_LICENSE:
@@ -325,15 +325,15 @@ static BOOL peer_recv_callback(rdpTransport* transport, STREAM* s, void* extra)
 
 		case CONNECTION_STATE_ACTIVE:
 			if (!peer_recv_pdu(client, s))
-				return FALSE;
+				return -1;
 			break;
 
 		default:
 			printf("Invalid state %d\n", rdp->state);
-			return FALSE;
+			return -1;
 	}
 
-	return TRUE;
+	return 0;
 }
 
 static BOOL freerdp_peer_close(freerdp_peer* client)
diff --git a/libfreerdp/core/rdp.c b/libfreerdp/core/rdp.c
index 999e7b567..2c10b1b61 100644
--- a/libfreerdp/core/rdp.c
+++ b/libfreerdp/core/rdp.c
@@ -850,50 +850,50 @@ static BOOL rdp_recv_callback(rdpTransport* transport, STREAM* s, void* extra)
 	{
 		case CONNECTION_STATE_NEGO:
 			if (!rdp_client_connect_mcs_connect_response(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_MCS_ATTACH_USER:
 			if (!rdp_client_connect_mcs_attach_user_confirm(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_MCS_CHANNEL_JOIN:
 			if (!rdp_client_connect_mcs_channel_join_confirm(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_LICENSE:
 			if (!rdp_client_connect_license(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		case CONNECTION_STATE_CAPABILITY:
 			if (!rdp_client_connect_demand_active(rdp, s))
 			{
 				printf("rdp_client_connect_demand_active failed\n");
-				return FALSE;
+				return -1;
 			}
 			break;
 
 		case CONNECTION_STATE_FINALIZATION:
 			if (!rdp_recv_pdu(rdp, s))
-				return FALSE;
+				return -1;
 			if (rdp->finalize_sc_pdus == FINALIZE_SC_COMPLETE)
 				rdp->state = CONNECTION_STATE_ACTIVE;
 			break;
 
 		case CONNECTION_STATE_ACTIVE:
 			if (!rdp_recv_pdu(rdp, s))
-				return FALSE;
+				return -1;
 			break;
 
 		default:
 			printf("Invalid state %d\n", rdp->state);
-			return FALSE;
+			return -1;
 	}
 
-	return TRUE;
+	return 0;
 }
 
 int rdp_send_channel_data(rdpRdp* rdp, int channel_id, BYTE* data, int size)
diff --git a/libfreerdp/core/transport.c b/libfreerdp/core/transport.c
index 75287059d..fc2be7b3a 100644
--- a/libfreerdp/core/transport.c
+++ b/libfreerdp/core/transport.c
@@ -589,6 +589,7 @@ int transport_check_fds(rdpTransport** ptransport)
 	int pos;
 	int status;
 	UINT16 length;
+	int recv_status;
 	STREAM* received;
 	rdpTransport* transport = *ptransport;
 
@@ -684,10 +685,21 @@ int transport_check_fds(rdpTransport** ptransport)
 		stream_seal(received);
 		stream_set_pos(received, 0);
 
-		if (transport->ReceiveCallback(transport, received, transport->ReceiveExtra) == FALSE)
+		/**
+		 * ReceiveCallback return values:
+		 *
+		 * -1: synchronous failure
+		 *  0: synchronous success
+		 *  1: asynchronous return
+		 */
+
+		recv_status = transport->ReceiveCallback(transport, received, transport->ReceiveExtra);
+
+		if (recv_status < 0)
 			status = -1;
 
-		transport_receive_pool_return(transport, received);
+		if (recv_status == 0)
+			transport_receive_pool_return(transport, received);
 
 		if (status < 0)
 			return status;
diff --git a/winpr/libwinpr/crypto/test/TestCertEnumCertificatesInStore.c b/winpr/libwinpr/crypto/test/TestCertEnumCertificatesInStore.c
index 5f81415a4..d4a909e5a 100644
--- a/winpr/libwinpr/crypto/test/TestCertEnumCertificatesInStore.c
+++ b/winpr/libwinpr/crypto/test/TestCertEnumCertificatesInStore.c
@@ -41,7 +41,7 @@ int TestCertEnumCertificatesInStore(int argc, char* argv[])
 
 	index = 0;
 
-	while (pCertContext = CertEnumCertificatesInStore(hCertStore, pCertContext))
+	while ((pCertContext = CertEnumCertificatesInStore(hCertStore, pCertContext)))
 	{
 		status = CertGetNameString(pCertContext, CERT_NAME_SIMPLE_DISPLAY_TYPE, 0, NULL, NULL, 0);