Add API for get the memory stats (#1923)

JerryScript-DCO-1.0-Signed-off-by: Zidong Jiang zidong.jiang@intel.com

jerry-core/api/jerry.c

@@ -33,6 +33,7 @@
 #include "ecma-promise-object.h"
 #include "jcontext.h"
 #include "jerryscript.h"
+#include "jmem.h"
 #include "js-parser.h"
 #include "re-compiler.h"
 
@@ -254,6 +255,39 @@ jerry_gc (void)
   ecma_gc_run (JMEM_FREE_UNUSED_MEMORY_SEVERITY_LOW);
 } /* jerry_gc */
 
+/**
+ * Get heap memory stats.
+ *
+ * @return true - get the heap stats successful
+ *         false - otherwise. Usually it is because the MEM_STATS feature is not enabled.
+ */
+bool
+jerry_get_memory_stats (jerry_heap_stats_t *out_stats_p) /**< [out] heap memory stats */
+{
+#ifdef JMEM_STATS
+  if (out_stats_p == NULL)
+  {
+    return false;
+  }
+
+  jmem_heap_stats_t jmem_heap_stats = {0};
+  jmem_heap_get_stats (&jmem_heap_stats);
+
+  *out_stats_p = (jerry_heap_stats_t)
+  {
+    .version = 1,
+    .size = jmem_heap_stats.size,
+    .allocated_bytes = jmem_heap_stats.allocated_bytes,
+    .peak_allocated_bytes = jmem_heap_stats.peak_allocated_bytes
+  };
+
+  return true;
+#else
+  JERRY_UNUSED (out_stats_p);
+  return false;
+#endif
+} /* jerry_get_memory_stats */
+
 /**
  * Simple Jerry runner
  *