Add enable/disable cb function in mem_trace

platform/mbed_mem_trace.cpp

@@ -28,6 +28,7 @@
 
 /* The callback function that will be called after a traced memory operations finishes. */
 static mbed_mem_trace_cb_t mem_trace_cb;
+static mbed_mem_trace_cb_t mem_trace_cb_reserve;
 /* 'trace_lock_count' guards "trace inside trace" situations (for example, the implementation
  * of realloc() might call malloc() internally, and since malloc() is also traced, this could
  * result in two calls to the callback function instead of one. */
@@ -46,6 +47,24 @@ void mbed_mem_trace_set_callback(mbed_mem_trace_cb_t cb)
     mem_trace_cb = cb;
 }
 
+void mbed_mem_trace_disable()
+{
+    mbed_mem_trace_lock();
+    if (mem_trace_cb) {
+        mem_trace_cb_reserve = mem_trace_cb;
+        mem_trace_cb = 0;
+    }
+    mbed_mem_trace_unlock();
+}
+void mbed_mem_trace_enable()
+{
+    mbed_mem_trace_lock();
+    if (!mem_trace_cb && mem_trace_cb_reserve) {
+        mem_trace_cb = mem_trace_cb_reserve;
+    }
+    mbed_mem_trace_unlock();
+}
+
 void mbed_mem_trace_lock()
 {
     mem_trace_mutex->lock();

platform/mbed_mem_trace.h

@@ -72,6 +72,16 @@ typedef void (*mbed_mem_trace_cb_t)(uint8_t op, void *res, void *caller, ...);
  */
 void mbed_mem_trace_set_callback(mbed_mem_trace_cb_t cb);
 
+/**
+ * Disable the memory trace output by disabling the callback function
+ */
+void mbed_mem_trace_disable();
+
+/**
+ * Renable the memory trace output with the cb in use when disable was called
+ */
+void mbed_mem_trace_enable();
+
 /**
  * Trace lock.
  * @note Locking prevent recursive tracing of malloc/free inside relloc/calloc