component/bt: Avoid A2DP demo to use unallocated memory

examples/bluetooth/bluedroid/classic_bt/a2dp_sink/main/bt_app_core.c

@@ -26,7 +26,7 @@ static void bt_app_work_dispatched(bt_app_msg_t *msg);
 static xQueueHandle s_bt_app_task_queue = NULL;
 static xTaskHandle s_bt_app_task_handle = NULL;
 static xTaskHandle s_bt_i2s_task_handle = NULL;
-static RingbufHandle_t ringbuf_i2s = NULL;;
+static RingbufHandle_t s_ringbuf_i2s = NULL;;
 
 bool bt_app_work_dispatch(bt_app_cb_t p_cback, uint16_t event, void *p_params, int param_len, bt_app_copy_cb_t p_copy_cback)
 {
@@ -123,18 +123,18 @@ static void bt_i2s_task_handler(void *arg)
     size_t bytes_written = 0;
 
     for (;;) {
-        data = (uint8_t *)xRingbufferReceive(ringbuf_i2s, &item_size, (portTickType)portMAX_DELAY);
+        data = (uint8_t *)xRingbufferReceive(s_ringbuf_i2s, &item_size, (portTickType)portMAX_DELAY);
         if (item_size != 0){
             i2s_write(0, data, item_size, &bytes_written, portMAX_DELAY);
-            vRingbufferReturnItem(ringbuf_i2s,(void *)data);
+            vRingbufferReturnItem(s_ringbuf_i2s,(void *)data);
         }
     }
 }
 
 void bt_i2s_task_start_up(void)
 {
-    ringbuf_i2s = xRingbufferCreate(8 * 1024, RINGBUF_TYPE_BYTEBUF);
-    if(ringbuf_i2s == NULL){
+    s_ringbuf_i2s = xRingbufferCreate(8 * 1024, RINGBUF_TYPE_BYTEBUF);
+    if(s_ringbuf_i2s == NULL){
         return;
     }
 
@@ -149,13 +149,15 @@ void bt_i2s_task_shut_down(void)
         s_bt_i2s_task_handle = NULL;
     }
 
-    vRingbufferDelete(ringbuf_i2s);
-    ringbuf_i2s = NULL;
+    if (s_ringbuf_i2s) {
+        vRingbufferDelete(s_ringbuf_i2s);
+        s_ringbuf_i2s = NULL;
+    }
 }
 
 size_t write_ringbuf(const uint8_t *data, size_t size)
 {
-    BaseType_t done = xRingbufferSend(ringbuf_i2s, (void *)data, size, (portTickType)portMAX_DELAY);
+    BaseType_t done = xRingbufferSend(s_ringbuf_i2s, (void *)data, size, (portTickType)portMAX_DELAY);
     if(done){
         return size;
     } else {

examples/bluetooth/bluedroid/coex/a2dp_gatts_coex/main/bt_app_core.c

@@ -26,7 +26,7 @@ static void bt_app_work_dispatched(bt_app_msg_t *msg);
 static xQueueHandle s_bt_app_task_queue = NULL;
 static xTaskHandle s_bt_app_task_handle = NULL;
 static xTaskHandle s_bt_i2s_task_handle = NULL;
-static RingbufHandle_t ringbuf_i2s = NULL;;
+static RingbufHandle_t s_ringbuf_i2s = NULL;;
 
 bool bt_app_work_dispatch(bt_app_cb_t p_cback, uint16_t event, void *p_params, int param_len, bt_app_copy_cb_t p_copy_cback)
 {
@@ -123,18 +123,18 @@ static void bt_i2s_task_handler(void *arg)
     size_t bytes_written = 0;
 
     for (;;) {
-        data = (uint8_t *)xRingbufferReceive(ringbuf_i2s, &item_size, (portTickType)portMAX_DELAY);
+        data = (uint8_t *)xRingbufferReceive(s_ringbuf_i2s, &item_size, (portTickType)portMAX_DELAY);
         if (item_size != 0){
             i2s_write(0, data, item_size, &bytes_written, portMAX_DELAY);
-            vRingbufferReturnItem(ringbuf_i2s,(void *)data);
+            vRingbufferReturnItem(s_ringbuf_i2s,(void *)data);
         }
     }
 }
 
 void bt_i2s_task_start_up(void)
 {
-    ringbuf_i2s = xRingbufferCreate(8 * 1024, RINGBUF_TYPE_BYTEBUF);
-    if(ringbuf_i2s == NULL){
+    s_ringbuf_i2s = xRingbufferCreate(8 * 1024, RINGBUF_TYPE_BYTEBUF);
+    if(s_ringbuf_i2s == NULL){
         return;
     }
 
@@ -149,13 +149,15 @@ void bt_i2s_task_shut_down(void)
         s_bt_i2s_task_handle = NULL;
     }
 
-    vRingbufferDelete(ringbuf_i2s);
-    ringbuf_i2s = NULL;
+    if (s_ringbuf_i2s) {
+        vRingbufferDelete(s_ringbuf_i2s);
+        s_ringbuf_i2s = NULL;
+    }
 }
 
 size_t write_ringbuf(const uint8_t *data, size_t size)
 {
-    BaseType_t done = xRingbufferSend(ringbuf_i2s, (void *)data, size, (portTickType)portMAX_DELAY);
+    BaseType_t done = xRingbufferSend(s_ringbuf_i2s, (void *)data, size, (portTickType)portMAX_DELAY);
     if(done){
         return size;
     } else {