Coverity issues fixed

UNITTESTS/stubs/CellularUtil_stub.cpp

@@ -110,6 +110,11 @@ int hex_str_to_char_str(const char *str, uint16_t len, char *buf)
     return 1;
 }
 
+void hex_to_char(const char *hex, char &buf)
+{
+    buf = CellularUtil_stub::char_ptr[CellularUtil_stub::char_pos++];
+}
+
 void uint_to_binary_str(uint32_t num, char *str, int str_size, int bit_cnt)
 {
 

components/wifi/esp8266-driver/ESP8266/ESP8266.cpp

@@ -49,12 +49,14 @@ ESP8266::ESP8266(PinName tx, PinName rx, bool debug, PinName rts, PinName cts)
       _parser(&_serial),
       _packets(0),
       _packets_end(&_packets),
+      _sock_active_id(-1),
       _heap_usage(0),
       _connect_error(0),
       _disconnect(false),
       _fail(false),
       _sock_already(false),
       _closed(false),
+      _error(false),
       _busy(false),
       _reset_check(_rmutex),
       _reset_done(false),
@@ -97,6 +99,10 @@ ESP8266::ESP8266(PinName tx, PinName rx, bool debug, PinName rts, PinName cts)
         _sock_i[i].tcp_data_avbl = 0;
         _sock_i[i].tcp_data_rcvd = 0;
     }
+
+    _scan_r.res = NULL;
+    _scan_r.limit = 0;
+    _scan_r.cnt = 0;
 }
 
 bool ESP8266::at_available()
@@ -328,8 +334,8 @@ nsapi_error_t ESP8266::connect(const char *ap, const char *passPhrase)
     _smutex.lock();
     set_timeout(ESP8266_CONNECT_TIMEOUT);
 
-    _parser.send("AT+CWJAP_CUR=\"%s\",\"%s\"", ap, passPhrase);
+    bool res = _parser.send("AT+CWJAP_CUR=\"%s\",\"%s\"", ap, passPhrase);
-    if (!_parser.recv("OK\n")) {
+    if (!res || !_parser.recv("OK\n")) {
         if (_fail) {
             if (_connect_error == 1) {
                 ret = NSAPI_ERROR_CONNECTION_TIMEOUT;

components/wifi/esp8266-driver/ESP8266Interface.cpp

@@ -94,6 +94,7 @@ ESP8266Interface::ESP8266Interface(PinName tx, PinName rx, bool debug, PinName r
       _if_blocking(true),
       _if_connected(_cmutex),
       _initialized(false),
+      _connect_retval(NSAPI_ERROR_OK),
       _conn_stat(NSAPI_STATUS_DISCONNECTED),
       _conn_stat_cb(NULL),
       _global_event_queue(mbed_event_queue()), // Needs to be set before attaching event() to SIGIO
@@ -298,7 +299,7 @@ int ESP8266Interface::set_credentials(const char *ssid, const char *pass, nsapi_
         if (pass_length >= ESP8266_PASSPHRASE_MIN_LENGTH
                 && pass_length <= ESP8266_PASSPHRASE_MAX_LENGTH) {
             memset(ap_pass, 0, sizeof(ap_pass));
-            strncpy(ap_pass, pass, sizeof(ap_pass));
+            strncpy(ap_pass, pass, ESP8266_PASSPHRASE_MAX_LENGTH);
         } else {
             return NSAPI_ERROR_PARAMETER;
         }

features/cellular/framework/AT/ATHandler.cpp

@@ -698,7 +698,7 @@ ssize_t ATHandler::read_hex_string(char *buf, size_t size)
         } else {
             hexbuf[read_idx % 2] = c;
             if (read_idx % 2 == 1) {
-                hex_str_to_char_str(hexbuf, 2, buf + buf_idx);
+                hex_to_char(hexbuf, *(buf + buf_idx));
             }
         }
     }
@@ -923,7 +923,7 @@ void ATHandler::resp(const char *prefix, bool check_urc)
 
     while (!get_last_error()) {
 
-        match(CRLF, CRLF_LENGTH);
+        (void)match(CRLF, CRLF_LENGTH);
 
         if (match(OK, OK_LENGTH)) {
             set_scope(RespType);
@@ -1281,6 +1281,7 @@ void ATHandler::cmd_start_stop(const char *cmd, const char *cmd_chr, const char
 
 nsapi_error_t ATHandler::at_cmd_str(const char *cmd, const char *cmd_chr, char *resp_buf, size_t buf_size, const char *format, ...)
 {
+    MBED_ASSERT(strlen(cmd) < BUFF_SIZE);
     lock();
 
     handle_start(cmd, cmd_chr);

features/cellular/framework/AT/AT_CellularSMS.cpp

@@ -188,7 +188,7 @@ void AT_CellularSMS::cmt_urc()
 {
     tr_debug("CMT_URC called");
     //+CMT: <oa>,[<alpha>],<scts>[,<tooa>,<fo>,<pid>,<dcs>,<sca>,<tosca>,<length>]<CR><LF><data>
-    _at.consume_to_stop_tag();
+    (void)_at.consume_to_stop_tag();
     // call user defined callback function
     if (_cb) {
         _cb();
@@ -1205,7 +1205,7 @@ uint16_t AT_CellularSMS::unpack_7_bit_gsm_to_str(const char *str, int len, char
     char tmp1;
 
     if (padding_bits) {
-        hex_str_to_char_str(str, 2, &tmp);
+        hex_to_char(str, tmp);
         buf[decodedCount] = gsm_to_ascii[(tmp >> padding_bits) & 0x7F];
         strCount++;
         decodedCount++;
@@ -1213,19 +1213,19 @@ uint16_t AT_CellularSMS::unpack_7_bit_gsm_to_str(const char *str, int len, char
 
     while (strCount < len) {
         shift = (strCount - padding_bits) % 7;
-        hex_str_to_char_str(str + strCount * 2, 2, &tmp);
+        hex_to_char(str + strCount * 2, tmp);
         if (shift == 0) {
             buf[decodedCount] = gsm_to_ascii[tmp & 0x7F];
         } else if (shift == 6) {
-            hex_str_to_char_str(str + (strCount - 1) * 2, 2, &tmp1);
+            hex_to_char(str + (strCount - 1) * 2, tmp1);
             buf[decodedCount] = gsm_to_ascii[(((tmp1 >> 2)) | (tmp << 6)) & 0x7F];
             if (decodedCount + 1 < msg_len) {
-                hex_str_to_char_str(str + strCount * 2, 2, &tmp);
+                hex_to_char(str + strCount * 2, tmp);
                 decodedCount++;
                 buf[decodedCount] = gsm_to_ascii[(tmp >> 1) & 0x7F];
             }
         } else {
-            hex_str_to_char_str(str + (strCount - 1) * 2, 2, &tmp1);
+            hex_to_char(str + (strCount - 1) * 2, tmp1);
             buf[decodedCount] = gsm_to_ascii[(((tmp1 >> (8 - shift))) | ((tmp << shift))) & 0x7F];
         }
 

features/cellular/framework/common/CellularUtil.cpp

@@ -271,15 +271,22 @@ int hex_str_to_char_str(const char *str, uint16_t len, char *buf)
 {
     int strcount = 0;
     for (int i = 0; i + 1 < len; i += 2) {
-        int upper = hex_str_to_int(str + i, 1);
+        char tmp;
-        int lower = hex_str_to_int(str + i + 1, 1);
+        hex_to_char(str + i, tmp);
-        buf[strcount] = ((upper << 4) & 0xF0) | (lower & 0x0F);
+        buf[strcount] = tmp;
         strcount++;
     }
 
     return strcount;
 }
 
+void hex_to_char(const char *hex, char &buf)
+{
+    int upper = hex_str_to_int(hex, 1);
+    int lower = hex_str_to_int(hex + 1, 1);
+    buf = ((upper << 4) & 0xF0) | (lower & 0x0F);
+}
+
 void uint_to_binary_str(uint32_t num, char *str, int str_size, int bit_cnt)
 {
     if (!str || str_size < bit_cnt) {

features/cellular/framework/common/CellularUtil.h

@@ -105,6 +105,13 @@ int hex_str_to_int(const char *hex_string, int hex_string_length);
  */
 int hex_str_to_char_str(const char *str, uint16_t len, char *buf);
 
+/** Converts the given hex string to char
+ *
+ *  @param str A hex value that is converted to char
+ *  @param buf A char variable where result conversion is stored
+ */
+void hex_to_char(const char *hex, char &buf);
+
 /** Converts the given uint to binary string. Fills the given str starting from [0] with the number of bits defined by bit_cnt
  *  For example uint_to_binary_string(9, str, 10) would fill str "0000001001"
  *  For example uint_to_binary_string(9, str, 3) would fill str "001"

features/cellular/framework/targets/QUECTEL/M26/QUECTEL_M26_CellularStack.cpp

@@ -478,6 +478,7 @@ nsapi_size_or_error_t QUECTEL_M26_CellularStack::socket_sendto_impl(CellularSock
             _at.resp_start("+QISACK:");
             sent_len_before = _at.read_int();
             sent_acked = _at.read_int();
+            (void)sent_acked;
             sent_nacked = _at.read_int();
             _at.resp_stop();
 

features/lwipstack/LWIPStack.cpp

@@ -162,6 +162,7 @@ void LWIP::tcpip_init_irq(void *eh)
 LWIP::LWIP()
 {
     default_interface = NULL;
+    tcpip_thread_id = NULL;
 
     // Seed lwip random
     lwip_seed_random();
@@ -208,7 +209,9 @@ nsapi_error_t LWIP::add_dns_server(const SocketAddress &address, const char *int
     const ip_addr_t *ip_addr_move;
     ip_addr_t ip_addr;
 
-    convert_mbed_addr_to_lwip(&ip_addr, &addr);
+    if (!convert_mbed_addr_to_lwip(&ip_addr, &addr)) {
+        return NSAPI_ERROR_PARAMETER;
+    }
 
     if (ip_addr_isany(&ip_addr)) {
         return NSAPI_ERROR_NO_ADDRESS;