Returning an empty shared_ptr returns null to JavaScript. Similarly, passing null into a shared_ptr creates an empty shared_ptr.

2 files changed, 31 insertions, 3 deletions

diff --git a/src/embind/embind.js b/src/embind/embind.js
index bbbeb96c..98d4b13e 100644
--- a/src/embind/embind.js
+++ b/src/embind/embind.js
@@ -60,7 +60,9 @@ function __embind_register_bool(boolType, name, trueValue, falseValue) {
             return o ? trueValue : falseValue;
         },
         fromWireType: function(wt) {
-            return wt === trueValue;
+            // ambiguous emscripten ABI: sometimes return values are
+            // true or false, and sometimes integers (0 or 1)
+            return !!wt;
         },
     });
 }
@@ -397,7 +399,7 @@ function __embind_register_smart_ptr(
     };
     
     Handle.prototype['delete'] = function() {
-        if (!this.ptr && !this.smartPointer) {
+        if (!this.ptr) {
             throw new BindingError(pointeeType.name + ' instance already deleted');
         }
         
@@ -412,10 +414,18 @@ function __embind_register_smart_ptr(
     registerType(pointerType, name, {
         name: name,
         fromWireType: function(ptr) {
+            if (!getPointee(ptr)) {
+                destructor(ptr);
+                return null;
+            }
             return new Handle(ptr);
         },
         toWireType: function(destructors, o) {
-            return o.smartPointer;
+            if (null === o) {
+                return 0;
+            } else {
+                return o.smartPointer;
+            }
         }
     });
 }
diff --git a/system/include/emscripten/wire.h b/system/include/emscripten/wire.h
index 89e68c68..452628a0 100644
--- a/system/include/emscripten/wire.h
+++ b/system/include/emscripten/wire.h
@@ -210,6 +210,24 @@ namespace emscripten {
             }
         };
 
+        template<typename T>
+        struct BindingType<std::shared_ptr<T>> {
+            typedef std::shared_ptr<T> shared_ptr;
+            typedef std::shared_ptr<T>* WireType;
+
+            static WireType toWireType(shared_ptr p) {
+                return new shared_ptr(p);
+            }
+
+            static shared_ptr fromWireType(WireType wt) {
+                if (wt) {
+                    return shared_ptr(*wt);
+                } else {
+                    return shared_ptr();
+                }
+            }
+        };
+
         template<typename Enum>
         struct EnumBindingType {
             typedef Enum WireType;