CSE2410 Fall 2014 Bounce

// Copyright Joyent, Inc. and other Node contributors.

//

// Permission is hereby granted, free of charge, to any person obtaining a

// copy of this software and associated documentation files (the

// "Software"), to deal in the Software without restriction, including

// without limitation the rights to use, copy, modify, merge, publish,

// distribute, sublicense, and/or sell copies of the Software, and to permit

// persons to whom the Software is furnished to do so, subject to the

// following conditions:

//

// The above copyright notice and this permission notice shall be included

// in all copies or substantial portions of the Software.

//

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN

// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,

// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR

// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE

// USE OR OTHER DEALINGS IN THE SOFTWARE.

#include "node.h"

#include "node_buffer.h"

#include "slab_allocator.h"

#include "req_wrap.h"

#include "handle_wrap.h"

#include "udp_wrap.h"

#include <stdlib.h>

#define SLAB_SIZE (1024 * 1024)

// Temporary hack: libuv should provide uv_inet_pton and uv_inet_ntop.

// Clean this up in tcp_wrap.cc too.

#if defined(__MINGW32__) || defined(_MSC_VER)

  extern "C" {

#   include <inet_net_pton.h>

#   include <inet_ntop.h>

  }

# define uv_inet_pton ares_inet_pton

# define uv_inet_ntop ares_inet_ntop

#else // __POSIX__

# include <arpa/inet.h>

# define uv_inet_pton inet_pton

# define uv_inet_ntop inet_ntop

#endif

using namespace v8;

namespace node {

typedef ReqWrap<uv_udp_send_t> SendWrap;

// see tcp_wrap.cc

Local<Object> AddressToJS(const sockaddr* addr);

static Persistent<String> buffer_sym;

static Persistent<String> oncomplete_sym;

static Persistent<String> onmessage_sym;

static SlabAllocator* slab_allocator;

static void DeleteSlabAllocator(void*) {

  delete slab_allocator;

  slab_allocator = NULL;

}

UDPWrap::UDPWrap(Handle<Object> object): HandleWrap(object,

                                                    (uv_handle_t*)&handle_) {

  int r = uv_udp_init(uv_default_loop(), &handle_);

  assert(r == 0); // can't fail anyway

  handle_.data = reinterpret_cast<void*>(this);

}

UDPWrap::~UDPWrap() {

}

void UDPWrap::Initialize(Handle<Object> target) {

  HandleWrap::Initialize(target);

  slab_allocator = new SlabAllocator(SLAB_SIZE);

  AtExit(DeleteSlabAllocator, NULL);

  HandleScope scope;

  buffer_sym = NODE_PSYMBOL("buffer");

  oncomplete_sym = NODE_PSYMBOL("oncomplete");

  onmessage_sym = NODE_PSYMBOL("onmessage");

  Local<FunctionTemplate> t = FunctionTemplate::New(New);

  t->InstanceTemplate()->SetInternalFieldCount(1);

  t->SetClassName(String::NewSymbol("UDP"));

  NODE_SET_PROTOTYPE_METHOD(t, "bind", Bind);

  NODE_SET_PROTOTYPE_METHOD(t, "send", Send);

  NODE_SET_PROTOTYPE_METHOD(t, "bind6", Bind6);

  NODE_SET_PROTOTYPE_METHOD(t, "send6", Send6);

  NODE_SET_PROTOTYPE_METHOD(t, "close", Close);

  NODE_SET_PROTOTYPE_METHOD(t, "recvStart", RecvStart);

  NODE_SET_PROTOTYPE_METHOD(t, "recvStop", RecvStop);

  NODE_SET_PROTOTYPE_METHOD(t, "getsockname", GetSockName);

  NODE_SET_PROTOTYPE_METHOD(t, "addMembership", AddMembership);

  NODE_SET_PROTOTYPE_METHOD(t, "dropMembership", DropMembership);

  NODE_SET_PROTOTYPE_METHOD(t, "setMulticastTTL", SetMulticastTTL);

  NODE_SET_PROTOTYPE_METHOD(t, "setMulticastLoopback", SetMulticastLoopback);

  NODE_SET_PROTOTYPE_METHOD(t, "setBroadcast", SetBroadcast);

  NODE_SET_PROTOTYPE_METHOD(t, "setTTL", SetTTL);

  target->Set(String::NewSymbol("UDP"),

              Persistent<FunctionTemplate>::New(t)->GetFunction());

}

Handle<Value> UDPWrap::New(const Arguments& args) {

  HandleScope scope;

  assert(args.IsConstructCall());

  new UDPWrap(args.This());

  return scope.Close(args.This());

}

Handle<Value> UDPWrap::DoBind(const Arguments& args, int family) {

  HandleScope scope;

  int r;

  UNWRAP(UDPWrap)

  // bind(ip, port, flags)

  assert(args.Length() == 3);

  String::Utf8Value address(args[0]);

  const int port = args[1]->Uint32Value();

  const int flags = args[2]->Uint32Value();

  switch (family) {

  case AF_INET:

    r = uv_udp_bind(&wrap->handle_, uv_ip4_addr(*address, port), flags);

    break;

  case AF_INET6:

    r = uv_udp_bind6(&wrap->handle_, uv_ip6_addr(*address, port), flags);

    break;

  default:

    assert(0 && "unexpected address family");

    abort();

  }

  if (r)

    SetErrno(uv_last_error(uv_default_loop()));

  return scope.Close(Integer::New(r));

}

Handle<Value> UDPWrap::Bind(const Arguments& args) {

  return DoBind(args, AF_INET);

}

Handle<Value> UDPWrap::Bind6(const Arguments& args) {

  return DoBind(args, AF_INET6);

}

#define X(name, fn)                                                           \

  Handle<Value> UDPWrap::name(const Arguments& args) {                        \

    HandleScope scope;                                                        \

    UNWRAP(UDPWrap)                                                                    \

    assert(args.Length() == 1);                                               \

    int flag = args[0]->Int32Value();                                         \

    int r = fn(&wrap->handle_, flag);                                         \

    if (r) SetErrno(uv_last_error(uv_default_loop()));                        \

    return scope.Close(Integer::New(r));                                      \

  }

X(SetTTL, uv_udp_set_ttl)

X(SetBroadcast, uv_udp_set_broadcast)

X(SetMulticastTTL, uv_udp_set_multicast_ttl)

X(SetMulticastLoopback, uv_udp_set_multicast_loop)

#undef X

Handle<Value> UDPWrap::SetMembership(const Arguments& args,

                                     uv_membership membership) {

  HandleScope scope;

  UNWRAP(UDPWrap)

  assert(args.Length() == 2);

  String::Utf8Value address(args[0]);

  String::Utf8Value iface(args[1]);

  const char* iface_cstr = *iface;

  if (args[1]->IsUndefined() || args[1]->IsNull()) {

      iface_cstr = NULL;

  }

  int r = uv_udp_set_membership(&wrap->handle_, *address, iface_cstr,

                                membership);

  if (r)

    SetErrno(uv_last_error(uv_default_loop()));

  return scope.Close(Integer::New(r));

}

Handle<Value> UDPWrap::AddMembership(const Arguments& args) {

  return SetMembership(args, UV_JOIN_GROUP);

}

Handle<Value> UDPWrap::DropMembership(const Arguments& args) {

  return SetMembership(args, UV_LEAVE_GROUP);

}

Handle<Value> UDPWrap::DoSend(const Arguments& args, int family) {

  HandleScope scope;

  int r;

  // send(buffer, offset, length, port, address)

  assert(args.Length() == 5);

  UNWRAP(UDPWrap)

  assert(Buffer::HasInstance(args[0]));

  Local<Object> buffer_obj = args[0]->ToObject();

  size_t offset = args[1]->Uint32Value();

  size_t length = args[2]->Uint32Value();

  assert(offset < Buffer::Length(buffer_obj));

  assert(length <= Buffer::Length(buffer_obj) - offset);

  SendWrap* req_wrap = new SendWrap();

  req_wrap->object_->SetHiddenValue(buffer_sym, buffer_obj);

  uv_buf_t buf = uv_buf_init(Buffer::Data(buffer_obj) + offset,

                             length);

  const unsigned short port = args[3]->Uint32Value();

  String::Utf8Value address(args[4]);

  switch (family) {

  case AF_INET:

    r = uv_udp_send(&req_wrap->req_, &wrap->handle_, &buf, 1,

                    uv_ip4_addr(*address, port), OnSend);

    break;

  case AF_INET6:

    r = uv_udp_send6(&req_wrap->req_, &wrap->handle_, &buf, 1,

                     uv_ip6_addr(*address, port), OnSend);

    break;

  default:

    assert(0 && "unexpected address family");

    abort();

  }

  req_wrap->Dispatched();

  if (r) {

    SetErrno(uv_last_error(uv_default_loop()));

    delete req_wrap;

    return Null();

  }

  else {

    return scope.Close(req_wrap->object_);

  }

}

Handle<Value> UDPWrap::Send(const Arguments& args) {

  return DoSend(args, AF_INET);

}

Handle<Value> UDPWrap::Send6(const Arguments& args) {

  return DoSend(args, AF_INET6);

}

Handle<Value> UDPWrap::RecvStart(const Arguments& args) {

  HandleScope scope;

  UNWRAP(UDPWrap)

  // UV_EALREADY means that the socket is already bound but that's okay

  int r = uv_udp_recv_start(&wrap->handle_, OnAlloc, OnRecv);

  if (r && uv_last_error(uv_default_loop()).code != UV_EALREADY) {

    SetErrno(uv_last_error(uv_default_loop()));

    return False();

  }

  return True();

}

Handle<Value> UDPWrap::RecvStop(const Arguments& args) {

  HandleScope scope;

  UNWRAP(UDPWrap)

  int r = uv_udp_recv_stop(&wrap->handle_);

  return scope.Close(Integer::New(r));

}

Handle<Value> UDPWrap::GetSockName(const Arguments& args) {

  HandleScope scope;

  struct sockaddr_storage address;

  UNWRAP(UDPWrap)

  int addrlen = sizeof(address);

  int r = uv_udp_getsockname(&wrap->handle_,

                             reinterpret_cast<sockaddr*>(&address),

                             &addrlen);

  if (r) {

    SetErrno(uv_last_error(uv_default_loop()));

    return Null();

  }

  const sockaddr* addr = reinterpret_cast<const sockaddr*>(&address);

  return scope.Close(AddressToJS(addr));

}

// TODO share with StreamWrap::AfterWrite() in stream_wrap.cc

void UDPWrap::OnSend(uv_udp_send_t* req, int status) {

  HandleScope scope;

  assert(req != NULL);

  SendWrap* req_wrap = reinterpret_cast<SendWrap*>(req->data);

  UDPWrap* wrap = reinterpret_cast<UDPWrap*>(req->handle->data);

  assert(req_wrap->object_.IsEmpty() == false);

  assert(wrap->object_.IsEmpty() == false);

  if (status) {

    SetErrno(uv_last_error(uv_default_loop()));

  }

  Local<Value> argv[4] = {

    Integer::New(status),

    Local<Value>::New(wrap->object_),

    Local<Value>::New(req_wrap->object_),

    req_wrap->object_->GetHiddenValue(buffer_sym),

  };

  MakeCallback(req_wrap->object_, oncomplete_sym, ARRAY_SIZE(argv), argv);

  delete req_wrap;

}

uv_buf_t UDPWrap::OnAlloc(uv_handle_t* handle, size_t suggested_size) {

  UDPWrap* wrap = static_cast<UDPWrap*>(handle->data);

  char* buf = slab_allocator->Allocate(wrap->object_, suggested_size);

  return uv_buf_init(buf, suggested_size);

}

void UDPWrap::OnRecv(uv_udp_t* handle,

                     ssize_t nread,

                     uv_buf_t buf,

                     struct sockaddr* addr,

                     unsigned flags) {

  HandleScope scope;

  UDPWrap* wrap = reinterpret_cast<UDPWrap*>(handle->data);

  Local<Object> slab = slab_allocator->Shrink(wrap->object_,

                                              buf.base,

                                              nread < 0 ? 0 : nread);

  if (nread == 0) return;

  if (nread < 0) {

    Local<Value> argv[] = { Local<Object>::New(wrap->object_) };

    SetErrno(uv_last_error(uv_default_loop()));

    MakeCallback(wrap->object_, onmessage_sym, ARRAY_SIZE(argv), argv);

    return;

  }

  Local<Value> argv[] = {

    Local<Object>::New(wrap->object_),

    slab,

    Integer::NewFromUnsigned(buf.base - Buffer::Data(slab)),

    Integer::NewFromUnsigned(nread),

    AddressToJS(addr)

  };

  MakeCallback(wrap->object_, onmessage_sym, ARRAY_SIZE(argv), argv);

}

UDPWrap* UDPWrap::Unwrap(Local<Object> obj) {

  assert(!obj.IsEmpty());

  assert(obj->InternalFieldCount() > 0);

  return static_cast<UDPWrap*>(obj->GetPointerFromInternalField(0));

}

uv_udp_t* UDPWrap::UVHandle() {

  return &handle_;

}

} // namespace node

NODE_MODULE(node_udp_wrap, node::UDPWrap::Initialize)