Cellular: Fix socket bind tests for BG96

Author: Mirela Chirica

features/cellular/framework/AT/AT_CellularStack.cpp

@@ -198,15 +198,21 @@ nsapi_error_t AT_CellularStack::socket_bind(nsapi_socket_t handle, const SocketA
     }
 
     if (addr) {
-        socket->localAddress.set_addr(addr.get_addr());
-    }
-
-    if (addr.get_port()) {
-        socket->localAddress.set_port(addr.get_port());
+        return NSAPI_ERROR_UNSUPPORTED;
     }
 
     _at.lock();
 
+    uint16_t port = addr.get_port();
+    if (port != socket->localAddress.get_port()) {
+        if (port && (get_socket_index_by_port(port) == -1)) {
+            socket->localAddress.set_port(port);
+        } else {
+            _at.unlock();
+            return NSAPI_ERROR_PARAMETER;
+        }
+    }
+
     if (!socket->created) {
         create_socket_impl(socket);
     }
@@ -340,3 +346,14 @@ void AT_CellularStack::socket_attach(nsapi_socket_t handle, void (*callback)(voi
     socket->_cb = callback;
     socket->_data = data;
 }
+
+int AT_CellularStack::get_socket_index_by_port(uint16_t port)
+{
+    int max_socket_count = get_max_socket_count();
+    for (int i = 0; i < max_socket_count; i++) {
+        if (_socket[i]->localAddress.get_port() == port) {
+            return i;
+        }
+    }
+    return -1;
+}

features/cellular/framework/AT/AT_CellularStack.h

@@ -184,6 +184,8 @@ class AT_CellularStack : public NetworkStack, public AT_CellularBase {
 private:
     int find_socket_index(nsapi_socket_t handle);
 
+    int get_socket_index_by_port(uint16_t port);
+
     // mutex for write/read to a _socket array, needed when multiple threads may open sockets simultaneously
     PlatformMutex _socket_mutex;
 };

features/cellular/framework/targets/QUECTEL/BG96/QUECTEL_BG96_CellularStack.cpp

@@ -62,6 +62,10 @@ nsapi_error_t QUECTEL_BG96_CellularStack::socket_connect(nsapi_socket_t handle,
         handle_open_socket_response(modem_connect_id, err);
 
         if ((_at.get_last_error() == NSAPI_ERROR_OK) && err) {
+            if (err == BG96_SOCKET_BIND_FAIL) {
+                socket->created = false;
+                return NSAPI_ERROR_PARAMETER;
+            }
             _at.cmd_start("AT+QICLOSE=");
             _at.write_int(modem_connect_id);
             _at.cmd_stop();
@@ -178,6 +182,10 @@ nsapi_error_t QUECTEL_BG96_CellularStack::create_socket_impl(CellularSocket *soc
         handle_open_socket_response(modem_connect_id, err);
 
         if ((_at.get_last_error() == NSAPI_ERROR_OK) && err) {
+            if (err == BG96_SOCKET_BIND_FAIL) {
+                socket->created = false;
+                return NSAPI_ERROR_PARAMETER;
+            }
             _at.cmd_start("AT+QICLOSE=");
             _at.write_int(modem_connect_id);
             _at.cmd_stop_read_resp();
@@ -206,6 +214,10 @@ nsapi_error_t QUECTEL_BG96_CellularStack::create_socket_impl(CellularSocket *soc
         handle_open_socket_response(modem_connect_id, err);
 
         if ((_at.get_last_error() == NSAPI_ERROR_OK) && err) {
+            if (err == BG96_SOCKET_BIND_FAIL) {
+                socket->created = false;
+                return NSAPI_ERROR_PARAMETER;
+            }
             _at.cmd_start("AT+QICLOSE=");
             _at.write_int(modem_connect_id);
             _at.cmd_stop_read_resp();

features/cellular/framework/targets/QUECTEL/BG96/QUECTEL_BG96_CellularStack.h

@@ -25,6 +25,7 @@ namespace mbed {
 #define BG96_SOCKET_MAX 12
 #define BG96_CREATE_SOCKET_TIMEOUT 150000 //150 seconds
 #define BG96_CLOSE_SOCKET_TIMEOUT 20000 // TCP socket max timeout is >10sec
+#define BG96_SOCKET_BIND_FAIL 556
 
 class QUECTEL_BG96_CellularStack : public AT_CellularStack {
 public: