src/node/ext/slice.cc

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#include <node.h>
#include <nan.h>
#include <grpc/slice.h>
#include <grpc/support/alloc.h>

#include "slice.h"
#include "byte_buffer.h"

namespace grpc {
namespace node {

using Nan::Persistent;

using v8::Local;
using v8::String;
using v8::Value;

namespace {
void SliceFreeCallback(char *data, void *hint) {
  grpc_slice *slice = reinterpret_cast<grpc_slice*>(hint);
  grpc_slice_unref(*slice);
  delete slice;
}

void string_destroy_func(void *user_data) {
  delete reinterpret_cast<Nan::Utf8String*>(user_data);
}

void buffer_destroy_func(void *user_data) {
  delete reinterpret_cast<PersistentValue*>(user_data);
}
} // namespace

grpc_slice CreateSliceFromString(const Local<String> source) {
  Nan::HandleScope scope;
  Nan::Utf8String *utf8_value = new Nan::Utf8String(source);
  return grpc_slice_new_with_user_data(**utf8_value, source->Length(),
                                       string_destroy_func, utf8_value);
}

grpc_slice CreateSliceFromBuffer(const Local<Value> source) {
  // Prerequisite: ::node::Buffer::HasInstance(source)
  Nan::HandleScope scope;
  return grpc_slice_new_with_user_data(::node::Buffer::Data(source),
                                       ::node::Buffer::Length(source),
                                       buffer_destroy_func,
                                       new PersistentValue(source));
}
Local<String> CopyStringFromSlice(const grpc_slice slice) {
  Nan::EscapableHandleScope scope;
  if (GRPC_SLICE_LENGTH(slice) == 0) {
    return scope.Escape(Nan::EmptyString());
  }
  return scope.Escape(Nan::New<String>(
      const_cast<char *>(reinterpret_cast<const char *>(GRPC_SLICE_START_PTR(slice))),
      GRPC_SLICE_LENGTH(slice)).ToLocalChecked());
}

Local<Value> CreateBufferFromSlice(const grpc_slice slice) {
  Nan::EscapableHandleScope scope;
  grpc_slice *slice_ptr = new grpc_slice;
  *slice_ptr = grpc_slice_ref(slice);
  return scope.Escape(MakeFastBuffer(Nan::NewBuffer(
      const_cast<char *>(reinterpret_cast<const char *>(GRPC_SLICE_START_PTR(*slice_ptr))),
      GRPC_SLICE_LENGTH(*slice_ptr), SliceFreeCallback, slice_ptr).ToLocalChecked()));
}

}  // namespace node
}  // namespace grpc