return static_cast<uint32_t>(p[0] << 24U) |

static_cast<uint32_t>(p[1] << 16U) |

static_cast<uint32_t>(p[2] << 8U) |

static_cast<uint32_t>(p[3]);

ChannelWrap* channel;

ares_socket_t sock;

uv_poll_t poll_watcher;

size_t operator()(node_ares_task* a) const {

return std::hash<ares_socket_t>()(a->sock);

}

inline bool operator()(node_ares_task* a, node_ares_task* b) const {

return a->sock == b->sock;

}

public:

ChannelWrap(Environment* env, Local<Object> object);

~ChannelWrap();

static void New(const FunctionCallbackInfo<Value>& args);

void Setup();

void EnsureServers();

void StartTimer();

void CloseTimer();

void ModifyActivityQueryCount(int count);

inline uv_timer_t* timer_handle() { return timer_handle_; }

inline ares_channel cares_channel() { return channel_; }

inline bool query_last_ok() const { return query_last_ok_; }

inline void set_query_last_ok(bool ok) { query_last_ok_ = ok; }

inline bool is_servers_default() const { return is_servers_default_; }

inline void set_is_servers_default(bool is_default) {

is_servers_default_ = is_default;

}

inline int active_query_count() { return active_query_count_; }

inline node_ares_task_list* task_list() { return &task_list_; }

size_t self_size() const override { return sizeof(*this); }

static void AresTimeout(uv_timer_t* handle);

private:

uv_timer_t* timer_handle_;

ares_channel channel_;

bool query_last_ok_;

bool is_servers_default_;

bool library_inited_;

int active_query_count_;

node_ares_task_list task_list_;

Local<Object> object)

: AsyncWrap(env, object, PROVIDER_DNSCHANNEL),

timer_handle_(nullptr),

channel_(nullptr),

query_last_ok_(true),

is_servers_default_(true),

library_inited_(false),

active_query_count_(0) {

MakeWeak();

Setup();

CHECK(args.IsConstructCall());

CHECK_EQ(args.Length(), 0);

Environment* env = Environment::GetCurrent(args);

new ChannelWrap(env, args.This());

public:

GetAddrInfoReqWrap(Environment* env,

Local<Object> req_wrap_obj,

bool verbatim);

size_t self_size() const override { return sizeof(*this); }

bool verbatim() const { return verbatim_; }

private:

const bool verbatim_;

Local<Object> req_wrap_obj,

bool verbatim)

: ReqWrap(env, req_wrap_obj, AsyncWrap::PROVIDER_GETADDRINFOREQWRAP)

, verbatim_(verbatim) {

public:

GetNameInfoReqWrap(Environment* env, Local<Object> req_wrap_obj);

size_t self_size() const override { return sizeof(*this); }

ChannelWrap* channel = static_cast<ChannelWrap*>(handle->data);

CHECK_EQ(channel->timer_handle(), handle);

CHECK_EQ(false, channel->task_list()->empty());

ares_process_fd(channel->cares_channel(), ARES_SOCKET_BAD, ARES_SOCKET_BAD);

node_ares_task* task = ContainerOf(&node_ares_task::poll_watcher, watcher);

ChannelWrap* channel = task->channel;

/* Reset the idle timer */

uv_timer_again(channel->timer_handle());

if (status < 0) {

/* An error happened. Just pretend that the socket is both readable and */

/* writable. */

ares_process_fd(channel->cares_channel(), task->sock, task->sock);

return;

}

/* Process DNS responses */

ares_process_fd(channel->cares_channel(),

events & UV_READABLE ? task->sock : ARES_SOCKET_BAD,

events & UV_WRITABLE ? task->sock : ARES_SOCKET_BAD);

ares_socket_t sock,

int read,

int write) {

ChannelWrap* channel = static_cast<ChannelWrap*>(data);

node_ares_task* task;

node_ares_task lookup_task;

lookup_task.sock = sock;

auto it = channel->task_list()->find(&lookup_task);

task = (it == channel->task_list()->end()) ? nullptr : *it;

if (read || write) {

if (!task) {

/* New socket */

channel->StartTimer();

task = ares_task_create(channel, sock);

if (task == nullptr) {

/* This should never happen unless we're out of memory or something */

/* is seriously wrong. The socket won't be polled, but the query will */

/* eventually time out. */

return;

}

channel->task_list()->insert(task);

}

/* This should never fail. If it fails anyway, the query will eventually */

/* time out. */

uv_poll_start(&task->poll_watcher,

(read ? UV_READABLE : 0) | (write ? UV_WRITABLE : 0),

ares_poll_cb);

} else {

/* read == 0 and write == 0 this is c-ares's way of notifying us that */

/* the socket is now closed. We must free the data associated with */

/* socket. */

CHECK(task &&

"When an ares socket is closed we should have a handle for it");

channel->task_list()->erase(it);

channel->env()->CloseHandle(&task->poll_watcher, ares_poll_close_cb);

if (channel->task_list()->empty()) {

channel->CloseTimer();

}

}

struct hostent* host,

Local<Array> append_to = Local<Array>()) {

EscapableHandleScope scope(env->isolate());

auto context = env->context();

bool append = !append_to.IsEmpty();

Local<Array> names = append ? append_to : Array::New(env->isolate());

size_t offset = names->Length();

for (uint32_t i = 0; host->h_aliases[i] != nullptr; ++i) {

Local<String> address = OneByteString(env->isolate(), host->h_aliases[i]);

names->Set(context, i + offset, address).FromJust();

}

return append ? names : scope.Escape(names);

int idx;

if (host->h_addr_list != nullptr) {

idx = 0;

while (host->h_addr_list[idx]) {

free(host->h_addr_list[idx++]);

}

free(host->h_addr_list);

host->h_addr_list = 0;

}

if (host->h_aliases != nullptr) {

idx = 0;

while (host->h_aliases[idx]) {

free(host->h_aliases[idx++]);

}

free(host->h_aliases);

host->h_aliases = 0;

}

if (host->h_name != nullptr) {

free(host->h_name);

}

host->h_addrtype = host->h_length = 0;

dest->h_addr_list = nullptr;

dest->h_addrtype = 0;

dest->h_aliases = nullptr;

dest->h_length = 0;

dest->h_name = nullptr;

/* copy `h_name` */

size_t name_size = strlen(src->h_name) + 1;

dest->h_name = node::Malloc<char>(name_size);

memcpy(dest->h_name, src->h_name, name_size);

/* copy `h_aliases` */

size_t alias_count;

size_t cur_alias_length;

for (alias_count = 0;

src->h_aliases[alias_count] != nullptr;

alias_count++) {

}

dest->h_aliases = node::Malloc<char*>(alias_count + 1);

for (size_t i = 0; i < alias_count; i++) {

cur_alias_length = strlen(src->h_aliases[i]);

dest->h_aliases[i] = node::Malloc(cur_alias_length + 1);

memcpy(dest->h_aliases[i], src->h_aliases[i], cur_alias_length + 1);

}

dest->h_aliases[alias_count] = nullptr;

/* copy `h_addr_list` */

size_t list_count;

for (list_count = 0;

src->h_addr_list[list_count] != nullptr;

list_count++) {

}

dest->h_addr_list = node::Malloc<char*>(list_count + 1);

for (size_t i = 0; i < list_count; i++) {

dest->h_addr_list[i] = node::Malloc(src->h_length);

memcpy(dest->h_addr_list[i], src->h_addr_list[i], src->h_length);

}

dest->h_addr_list[list_count] = nullptr;

/* work after work */

dest->h_length = src->h_length;

dest->h_addrtype = src->h_addrtype;

QueryWrap* wrap;

int status;

bool is_host;

union {

hostent* host;

unsigned char* buf;

} data;

int len;

uv_async_t async_handle;

struct ares_options options;

memset(&options, 0, sizeof(options));

options.flags = ARES_FLAG_NOCHECKRESP;

options.sock_state_cb = ares_sockstate_cb;

options.sock_state_cb_data = this;

int r;

if (!library_inited_) {

Mutex::ScopedLock lock(ares_library_mutex);

// Multiple calls to ares_library_init() increase a reference counter,

// so this is a no-op except for the first call to it.

r = ares_library_init(ARES_LIB_INIT_ALL);

if (r != ARES_SUCCESS)

return env()->ThrowError(ToErrorCodeString(r));

}

/* We do the call to ares_init_option for caller. */

r = ares_init_options(&channel_,

&options,

ARES_OPT_FLAGS | ARES_OPT_SOCK_STATE_CB);

if (r != ARES_SUCCESS) {

Mutex::ScopedLock lock(ares_library_mutex);

ares_library_cleanup();

return env()->ThrowError(ToErrorCodeString(r));

}

library_inited_ = true;

if (timer_handle_ == nullptr) {

timer_handle_ = new uv_timer_t();

timer_handle_->data = static_cast<void*>(this);

uv_timer_init(env()->event_loop(), timer_handle_);

} else if (uv_is_active(reinterpret_cast<uv_handle_t*>(timer_handle_))) {

return;

}

uv_timer_start(timer_handle_, AresTimeout, 1000, 1000);

if (timer_handle_ == nullptr)

return;

env()->CloseHandle(timer_handle_, [](uv_timer_t* handle) { delete handle; });

timer_handle_ = nullptr;

/* if last query is OK or servers are set by user self, do not check */

if (query_last_ok_ || !is_servers_default_) {

return;

}

ares_addr_port_node* servers = nullptr;

ares_get_servers_ports(channel_, &servers);

/* if no server or multi-servers, ignore */

if (servers == nullptr) return;

if (servers->next != nullptr) {

ares_free_data(servers);

is_servers_default_ = false;

return;

}

/* if the only server is not 127.0.0.1, ignore */

if (servers[0].family != AF_INET ||

servers[0].addr.addr4.s_addr != htonl(INADDR_LOOPBACK) ||

servers[0].tcp_port != 0 ||

servers[0].udp_port != 0) {

ares_free_data(servers);

is_servers_default_ = false;

return;

}

ares_free_data(servers);

servers = nullptr;

/* destroy channel and reset channel */

ares_destroy(channel_);

CloseTimer();

Setup();

public:

QueryWrap(ChannelWrap* channel, Local<Object> req_wrap_obj)

: AsyncWrap(channel->env(), req_wrap_obj, AsyncWrap::PROVIDER_QUERYWRAP),

channel_(channel) {

// Make sure the channel object stays alive during the query lifetime.

req_wrap_obj->Set(env()->context(),

env()->channel_string(),

channel->object()).FromJust();

}

~QueryWrap() override {

CHECK_EQ(false, persistent().IsEmpty());

}

// Subclasses should implement the appropriate Send method.

virtual int Send(const char* name) {

UNREACHABLE();

return 0;

}

virtual int Send(const char* name, int family) {

UNREACHABLE();

return 0;

}

protected:

void AresQuery(const char* name,

int dnsclass,

int type) {

channel_->EnsureServers();

ares_query(channel_->cares_channel(), name, dnsclass, type, Callback,

static_cast<void*>(this));

}

static void CaresAsyncClose(uv_async_t* async) {

auto data = static_cast<struct CaresAsyncData*>(async->data);

delete data->wrap;

delete data;

}

static void CaresAsyncCb(uv_async_t* handle) {

auto data = static_cast<struct CaresAsyncData*>(handle->data);

QueryWrap* wrap = data->wrap;

int status = data->status;

if (status != ARES_SUCCESS) {

wrap->ParseError(status);

} else if (!data->is_host) {

unsigned char* buf = data->data.buf;

wrap->Parse(buf, data->len);

free(buf);

} else {

hostent* host = data->data.host;

wrap->Parse(host);

safe_free_hostent(host);

free(host);

}

wrap->env()->CloseHandle(handle, CaresAsyncClose);

}

static void Callback(void* arg, int status, int timeouts,

unsigned char* answer_buf, int answer_len) {

QueryWrap* wrap = static_cast<QueryWrap*>(arg);

unsigned char* buf_copy = nullptr;

if (status == ARES_SUCCESS) {

buf_copy = node::Malloc<unsigned char>(answer_len);

memcpy(buf_copy, answer_buf, answer_len);

}

CaresAsyncData* data = new CaresAsyncData();

data->status = status;

data->wrap = wrap;

data->is_host = false;

data->data.buf = buf_copy;

data->len = answer_len;

uv_async_t* async_handle = &data->async_handle;

CHECK_EQ(0, uv_async_init(wrap->env()->event_loop(),

async_handle,

CaresAsyncCb));

wrap->channel_->set_query_last_ok(status != ARES_ECONNREFUSED);

wrap->channel_->ModifyActivityQueryCount(-1);

async_handle->data = data;

uv_async_send(async_handle);

}

static void Callback(void* arg, int status, int timeouts,

struct hostent* host) {

QueryWrap* wrap = static_cast<QueryWrap*>(arg);

struct hostent* host_copy = nullptr;

if (status == ARES_SUCCESS) {

host_copy = node::Malloc<hostent>(1);

cares_wrap_hostent_cpy(host_copy, host);

}

CaresAsyncData* data = new CaresAsyncData();

data->status = status;

data->data.host = host_copy;

data->wrap = wrap;

data->is_host = true;

uv_async_t* async_handle = &data->async_handle;

CHECK_EQ(0, uv_async_init(wrap->env()->event_loop(),

async_handle,

CaresAsyncCb));

wrap->channel_->set_query_last_ok(status != ARES_ECONNREFUSED);

async_handle->data = data;

uv_async_send(async_handle);

}

void CallOnComplete(Local<Value> answer,

Local<Value> extra = Local<Value>()) {

HandleScope handle_scope(env()->isolate());

Context::Scope context_scope(env()->context());

Local<Value> argv[] = {

Integer::New(env()->isolate(), 0),

answer,

extra

};

const int argc = arraysize(argv) - extra.IsEmpty();

MakeCallback(env()->oncomplete_string(), argc, argv);

}

void ParseError(int status) {

CHECK_NE(status, ARES_SUCCESS);

HandleScope handle_scope(env()->isolate());

Context::Scope context_scope(env()->context());

const char* code = ToErrorCodeString(status);

Local<Value> arg = OneByteString(env()->isolate(), code);

MakeCallback(env()->oncomplete_string(), 1, &arg);

}

// Subclasses should implement the appropriate Parse method.

virtual void Parse(unsigned char* buf, int len) {

UNREACHABLE();

}

virtual void Parse(struct hostent* host) {

UNREACHABLE();

}

ChannelWrap* channel_;

const T* addrttls,

size_t naddrttls) {

auto isolate = env->isolate();

EscapableHandleScope escapable_handle_scope(isolate);

auto context = env->context();

Local<Array> ttls = Array::New(isolate, naddrttls);

for (size_t i = 0; i < naddrttls; i++) {

auto value = Integer::New(isolate, addrttls[i].ttl);

ttls->Set(context, i, value).FromJust();

}

return escapable_handle_scope.Escape(ttls);

const unsigned char* buf,

int len,

int* type,

Local<Array> ret,

void* addrttls = nullptr,

int* naddrttls = nullptr) {

HandleScope handle_scope(env->isolate());

auto context = env->context();

hostent* host;

int status;

switch (*type) {

case ns_t_a:

case ns_t_cname:

case ns_t_cname_or_a:

status = ares_parse_a_reply(buf,

len,

&host,

static_cast<ares_addrttl*>(addrttls),

naddrttls);

break;

case ns_t_aaaa:

status = ares_parse_aaaa_reply(buf,

len,

&host,

static_cast<ares_addr6ttl*>(addrttls),

naddrttls);

break;

case ns_t_ns:

status = ares_parse_ns_reply(buf, len, &host);

break;

case ns_t_ptr:

status = ares_parse_ptr_reply(buf, len, nullptr, 0, AF_INET, &host);

break;

default:

CHECK(0 && "Bad NS type");

break;

}

if (status != ARES_SUCCESS)

return status;

/* If it's `CNAME`, return the CNAME value;

if ((*type == ns_t_cname_or_a && host->h_name && host->h_aliases[0]) ||

*type == ns_t_cname) {

// A cname lookup always returns a single record but we follow the

// common API here.

*type = ns_t_cname;

ret->Set(context,

ret->Length(),

OneByteString(env->isolate(), host->h_name)).FromJust();

ares_free_hostent(host);

return ARES_SUCCESS;

}

if (*type == ns_t_cname_or_a)

*type = ns_t_a;

if (*type == ns_t_ns) {

HostentToNames(env, host, ret);

} else if (*type == ns_t_ptr) {

uint32_t offset = ret->Length();

for (uint32_t i = 0; host->h_aliases[i] != nullptr; i++) {

auto alias = OneByteString(env->isolate(), host->h_aliases[i]);

ret->Set(context, i + offset, alias).FromJust();

}

} else {

uint32_t offset = ret->Length();

char ip[INET6_ADDRSTRLEN];

for (uint32_t i = 0; host->h_addr_list[i] != nullptr; ++i) {

uv_inet_ntop(host->h_addrtype, host->h_addr_list[i], ip, sizeof(ip));

auto address = OneByteString(env->isolate(), ip);

ret->Set(context, i + offset, address).FromJust();

}

}

ares_free_hostent(host);

return ARES_SUCCESS;

const unsigned char* buf,

int len,

Local<Array> ret,

bool need_type = false) {

HandleScope handle_scope(env->isolate());

auto context = env->context();

struct ares_mx_reply* mx_start;

int status = ares_parse_mx_reply(buf, len, &mx_start);

if (status != ARES_SUCCESS) {

return status;

}

Local<String> exchange_symbol = env->exchange_string();

Local<String> priority_symbol = env->priority_string();

Local<String> type_symbol = env->type_string();

Local<String> mx_symbol = env->dns_mx_string();

uint32_t offset = ret->Length();

ares_mx_reply* current = mx_start;

for (uint32_t i = 0; current != nullptr; ++i, current = current->next) {

Local<Object> mx_record = Object::New(env->isolate());

mx_record->Set(context,

exchange_symbol,

OneByteString(env->isolate(), current->host)).FromJust();

mx_record->Set(context,

priority_symbol,

Integer::New(env->isolate(), current->priority)).FromJust();

if (need_type)

mx_record->Set(context, type_symbol, mx_symbol).FromJust();

ret->Set(context, i + offset, mx_record).FromJust();

}

ares_free_data(mx_start);

return ARES_SUCCESS;

const unsigned char* buf,

int len,

Local<Array> ret,

bool need_type = false) {

HandleScope handle_scope(env->isolate());

auto context = env->context();

struct ares_txt_ext* txt_out;

int status = ares_parse_txt_reply_ext(buf, len, &txt_out);

if (status != ARES_SUCCESS) {

return status;

}

Local<Array> txt_chunk;

struct ares_txt_ext* current = txt_out;

uint32_t i = 0, j;

uint32_t offset = ret->Length();

for (j = 0; current != nullptr; current = current->next) {

Local<String> txt = OneByteString(env->isolate(), current->txt);

// New record found - write out the current chunk

if (current->record_start) {

if (!txt_chunk.IsEmpty()) {

if (need_type) {

Local<Object> elem = Object::New(env->isolate());

elem->Set(context, env->entries_string(), txt_chunk).FromJust();

elem->Set(context,

env->type_string(),

env->dns_txt_string()).FromJust();

ret->Set(context, offset + i++, elem).FromJust();

} else {

ret->Set(context, offset + i++, txt_chunk).FromJust();

}

}

txt_chunk = Array::New(env->isolate());

j = 0;

}

txt_chunk->Set(context, j++, txt).FromJust();

}

// Push last chunk if it isn't empty

if (!txt_chunk.IsEmpty()) {

if (need_type) {

Local<Object> elem = Object::New(env->isolate());

elem->Set(context, env->entries_string(), txt_chunk).FromJust();

elem->Set(context,

env->type_string(),

env->dns_txt_string()).FromJust();

ret->Set(context, offset + i, elem).FromJust();

} else {

ret->Set(context, offset + i, txt_chunk).FromJust();

}

}

ares_free_data(txt_out);

return ARES_SUCCESS;

const unsigned char* buf,

int len,

Local<Array> ret,

bool need_type = false) {

HandleScope handle_scope(env->isolate());

auto context = env->context();

struct ares_srv_reply* srv_start;

int status = ares_parse_srv_reply(buf, len, &srv_start);

if (status != ARES_SUCCESS) {

return status;

}

Local<String> name_symbol = env->name_string();

Local<String> port_symbol = env->port_string();

Local<String> priority_symbol = env->priority_string();

Local<String> weight_symbol = env->weight_string();

Local<String> type_symbol = env->type_string();

Local<String> srv_symbol = env->dns_srv_string();

ares_srv_reply* current = srv_start;

int offset = ret->Length();

for (uint32_t i = 0; current != nullptr; ++i, current = current->next) {

Local<Object> srv_record = Object::New(env->isolate());

srv_record->Set(context,

name_symbol,

OneByteString(env->isolate(), current->host)).FromJust();

srv_record->Set(context,

port_symbol,

Integer::New(env->isolate(), current->port)).FromJust();

srv_record->Set(context,

priority_symbol,

Integer::New(env->isolate(), current->priority)).FromJust();

srv_record->Set(context,

weight_symbol,

Integer::New(env->isolate(), current->weight)).FromJust();

if (need_type)

srv_record->Set(context, type_symbol, srv_symbol).FromJust();

ret->Set(context, i + offset, srv_record).FromJust();

}

ares_free_data(srv_start);

return ARES_SUCCESS;

const unsigned char* buf,

int len,

Local<Array> ret,

bool need_type = false) {

HandleScope handle_scope(env->isolate());

auto context = env->context();

ares_naptr_reply* naptr_start;

int status = ares_parse_naptr_reply(buf, len, &naptr_start);

if (status != ARES_SUCCESS) {

return status;

}

Local<String> flags_symbol = env->flags_string();

Local<String> service_symbol = env->service_string();

Local<String> regexp_symbol = env->regexp_string();

Local<String> replacement_symbol = env->replacement_string();

Local<String> order_symbol = env->order_string();

Local<String> preference_symbol = env->preference_string();

Local<String> type_symbol = env->type_string();