Delete input buffer on postclose #151

Notify V8 GC of memory (de)allocation

src/resize.cc

@@ -51,7 +51,7 @@ enum class Angle {
 
 struct ResizeBaton {
   std::string fileIn;
-  void* bufferIn;
+  char* bufferIn;
   size_t bufferInLength;
   std::string iccProfilePath;
   int limitInputPixels;
@@ -125,6 +125,20 @@ struct ResizeBaton {
     }
 };
 
+/*
+  Delete input char[] buffer and notify V8 of memory deallocation
+  Used as the callback function for the "postclose" signal
+*/
+static void DeleteBuffer(VipsObject *object, std::tuple<char*, size_t> *buffer) {
+  char* data = std::get<0>(*buffer);
+  size_t length = std::get<1>(*buffer);
+  if (data != NULL) {
+    delete[] data;
+  }
+  NanAdjustExternalMemory(static_cast<int>(-length));
+  delete buffer;
+}
+
 class ResizeWorker : public NanAsyncWorker {
 
  public:
@@ -149,18 +163,25 @@ class ResizeWorker : public NanAsyncWorker {
 
     // Input
     ImageType inputImageType = ImageType::UNKNOWN;
-    VipsImage *image;
+    VipsImage *image = NULL;
     if (baton->bufferInLength > 1) {
       // From buffer
       inputImageType = DetermineImageType(baton->bufferIn, baton->bufferInLength);
+      std::tuple<char*, size_t> *buffer = new std::tuple<char*, size_t>(baton->bufferIn, baton->bufferInLength);
       if (inputImageType != ImageType::UNKNOWN) {
         image = InitImage(inputImageType, baton->bufferIn, baton->bufferInLength, baton->accessMethod);
-        if (image == NULL) {
+        if (image != NULL) {
+          // Listen for "postclose" signal to delete input buffer
+          g_signal_connect(image, "postclose", G_CALLBACK(DeleteBuffer), buffer);
+        } else {
+          // Could not read header data
           (baton->err).append("Input buffer has corrupt header");
           inputImageType = ImageType::UNKNOWN;
+          DeleteBuffer(NULL, buffer);
         }
       } else {
         (baton->err).append("Input buffer contains unsupported image format");
+        DeleteBuffer(NULL, buffer);
       }
     } else {
       // From file
@@ -175,7 +196,7 @@ class ResizeWorker : public NanAsyncWorker {
         (baton->err).append("Input file is of an unsupported image format");
       }
     }
-    if (inputImageType == ImageType::UNKNOWN) {
+    if (image == NULL || inputImageType == ImageType::UNKNOWN) {
       return Error(baton, hook);
     }
     vips_object_local(hook, image);
@@ -775,11 +796,6 @@ class ResizeWorker : public NanAsyncWorker {
   void HandleOKCallback () {
     NanScope();
 
-    // Free input Buffer
-    if (baton->bufferInLength > 0) {
-      g_free(baton->bufferIn);
-    }
-
     Handle<Value> argv[3] = { NanNull(), NanNull(),  NanNull() };
     if (!baton->err.empty()) {
       // Error
@@ -804,6 +820,7 @@ class ResizeWorker : public NanAsyncWorker {
       if (baton->bufferOutLength > 0) {
         // Copy data to new Buffer
         argv[1] = NanNewBufferHandle(static_cast<char*>(baton->bufferOut), baton->bufferOutLength);
+        // bufferOut was allocated via malloc
         g_free(baton->bufferOut);
         // Add buffer size to info
         info->Set(NanNew<String>("size"), NanNew<Uint32>(static_cast<uint32_t>(baton->bufferOutLength)));
@@ -925,9 +942,11 @@ NAN_METHOD(resize) {
     Local<Object> buffer = options->Get(NanNew<String>("bufferIn"))->ToObject();
     // Take a copy of the input Buffer to avoid problems with V8 heap compaction
     baton->bufferInLength = node::Buffer::Length(buffer);
-    baton->bufferIn = g_malloc(baton->bufferInLength);
+    baton->bufferIn = new char[baton->bufferInLength];
     memcpy(baton->bufferIn, node::Buffer::Data(buffer), baton->bufferInLength);
     options->Set(NanNew<String>("bufferIn"), NanNull());
+    // Notify V8 GC of memory allocation
+    NanAdjustExternalMemory(static_cast<int>(baton->bufferInLength));
   }
   // ICC profile to use when input CMYK image has no embedded profile
   baton->iccProfilePath = *String::Utf8Value(options->Get(NanNew<String>("iccProfilePath"))->ToString());