fix wifi example fail issue

Author: ian-qian-ting

features/FEATURE_LWIP/lwip-interface/lwipopts.h

@@ -83,13 +83,13 @@
 #ifdef LWIP_DEBUG
 #define TCPIP_THREAD_STACKSIZE      1200*2
 #else
-#define TCPIP_THREAD_STACKSIZE      1200
+#define TCPIP_THREAD_STACKSIZE      1600
 #endif
 
 #define TCPIP_THREAD_PRIO           (osPriorityNormal)
 
 #ifdef LWIP_DEBUG
-#define DEFAULT_THREAD_STACKSIZE    512*2
+#define DEFAULT_THREAD_STACKSIZE    1024*2
 #else
 #define DEFAULT_THREAD_STACKSIZE    512
 #endif

targets/TARGET_Realtek/TARGET_AMEBA/RTWInterface.cpp

@@ -186,8 +186,7 @@ nsapi_error_t RTWInterface::scan(WiFiAccessPoint *res, unsigned count)
 		} 
 		rtw_free_sema(&scan_sema);
 		return ApNum;
-
-	}else if(count > 0 && res != NULL){
+	}else if(count > 0 && res != NULL){
 		count = count < maxApNum ? count : maxApNum;
 		for(int i = 0; i < count; i++){
 			memcpy(&res[i], SCANED_AP[i], sizeof(WiFiAccessPoint));

targets/TARGET_Realtek/TARGET_AMEBA/sdk/lib_wlan_mbed.ar

@@ -39,14 +39,22 @@ int osdep_print = 0;
 void save_and_cli()
 {
 _func_enter_;
+#if defined(__CC_ARM)
+	rtw_enter_critical(NULL, NULL);
+#else
 	__disable_irq();
+#endif
 _func_exit_;
 }
 
 void restore_flags()
 {
 _func_enter_;
+#if defined(__CC_ARM)
+	rtw_exit_critical(NULL, NULL);
+#else
 	__enable_irq();
+#endif
 _func_exit_;
 }
 
@@ -966,13 +974,15 @@ u32  _rtx_timerStop( _timerHandle xTimer,
 {
 _func_enter_;
 	rtx_tmr_t *tmr = (rtx_tmr_t *) xTimer;
-	osStatus status = osTimerStop(tmr->id);
+	if(_rtx_timerIsTimerActive(xTimer) == _TRUE){
+		osStatus status = osTimerStop(tmr->id);
 _func_exit_;
-	if(status == osOK)
-		return _SUCCESS;
-
-	DBG_ERR("error %d\n", status);
-	return _FAIL;
+		if(status != osOK){
+			DBG_ERR("error %d\n", status);
+			return _FAIL;
+		}
+	}
+	return _SUCCESS;
 }
 
 u32  _rtx_timerChangePeriod( _timerHandle xTimer,