Merge pull request #6719 from murgatroid99/node_compressed_read_fix

Make Node not segfault when it receives a compressed message

src/node/ext/byte_buffer.cc

@@ -72,17 +72,13 @@ Local<Value> ByteBufferToBuffer(grpc_byte_buffer *buffer) {
   if (buffer == NULL) {
     return scope.Escape(Nan::Null());
   }
-  size_t length = grpc_byte_buffer_length(buffer);
-  char *result = new char[length];
-  size_t offset = 0;
   grpc_byte_buffer_reader reader;
   grpc_byte_buffer_reader_init(&reader, buffer);
-  gpr_slice next;
-  while (grpc_byte_buffer_reader_next(&reader, &next) != 0) {
-    memcpy(result + offset, GPR_SLICE_START_PTR(next), GPR_SLICE_LENGTH(next));
-    offset += GPR_SLICE_LENGTH(next);
-    gpr_slice_unref(next);
-  }
+  gpr_slice slice = grpc_byte_buffer_reader_readall(&reader);
+  size_t length = GPR_SLICE_LENGTH(slice);
+  char *result = new char[length];
+  memcpy(result, GPR_SLICE_START_PTR(slice), length);
+  gpr_slice_unref(slice);
   return scope.Escape(MakeFastBuffer(
       Nan::NewBuffer(result, length, delete_buffer, NULL).ToLocalChecked()));
 }