Cellular: Added BG96 handling for socket closing URC

Author: Mirela Chirica

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

@@ -20,6 +20,12 @@
 
 using namespace mbed;
 
+const char *QIURC_RECV = "recv";
+const uint8_t QIURC_RECV_LENGTH = 4;
+const char *QIURC_CLOSED = "closed";
+const uint8_t QIURC_CLOSED_LENGTH = 6;
+const uint8_t MAX_QIURC_LENGTH = QIURC_CLOSED_LENGTH;
+
 QUECTEL_BG96_CellularStack::QUECTEL_BG96_CellularStack(ATHandler &atHandler, int cid, nsapi_ip_stack_t stack_type) : AT_CellularStack(atHandler, cid, stack_type)
 {
     _at.set_urc_handler("+QIURC:", mbed::Callback<void()>(this, &QUECTEL_BG96_CellularStack::urc_qiurc));
@@ -110,20 +116,30 @@ nsapi_error_t QUECTEL_BG96_CellularStack::socket_connect(nsapi_socket_t handle,
 
 void QUECTEL_BG96_CellularStack::urc_qiurc()
 {
-    int sock_id = 0;
-
+    char urc_string[MAX_QIURC_LENGTH + 1];
     _at.lock();
-    (void) _at.skip_param();
-    sock_id = _at.read_int();
-    _at.unlock();
+    const int urc_string_length = _at.read_string(urc_string, sizeof(urc_string));
+    const int sock_id = _at.read_int();
+    const nsapi_error_t err = _at.unlock_return_error();
+
+    if (err != NSAPI_ERROR_OK) {
+        return;
+    }
+
+    bool recv = strcmp(urc_string, "recv") == 0;
+    bool closed = strcmp(urc_string, "closed") == 0;
+
+    CellularSocket *sock = find_socket(sock_id);
+    if (sock) {
+        if (closed) {
+            tr_error("Socket closed %d", sock_id);
+            sock->closed = true;
+        }
 
-    for (int i = 0; i < get_max_socket_count(); i++) {
-        CellularSocket *sock = _socket[i];
-        if (sock && sock->id == sock_id) {
+        if (recv || closed) {
             if (sock->_cb) {
                 sock->_cb(sock->_data);
             }
-            break;
         }
     }
 }