public:

typedef MaybeStackBuffer<char, 64> FSReqBuffer;

FSReqBase(Environment* env, Local<Object> req, AsyncWrap::ProviderType type)

: ReqWrap(env, req, type) {

}

void Init(const char* syscall,

const char* data,

size_t len,

enum encoding encoding) {

syscall_ = syscall;

encoding_ = encoding;

if (data != nullptr) {

CHECK(!has_data_);

buffer_.AllocateSufficientStorage(len + 1);

buffer_.SetLengthAndZeroTerminate(len);

memcpy(*buffer_, data, len);

has_data_ = true;

}

}

FSReqBuffer& Init(const char* syscall, size_t len,

enum encoding encoding) {

syscall_ = syscall;

encoding_ = encoding;

buffer_.AllocateSufficientStorage(len + 1);

has_data_ = false; // so that the data does not show up in error messages

return buffer_;

}

virtual void Reject(Local<Value> reject) = 0;

virtual void Resolve(Local<Value> value) = 0;

virtual void ResolveStat(const uv_stat_t* stat) = 0;

virtual void SetReturnValue(const FunctionCallbackInfo<Value>& args) = 0;

const char* syscall() const { return syscall_; }

const char* data() const { return has_data_ ? *buffer_ : nullptr; }

enum encoding encoding() const { return encoding_; }

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

private:

enum encoding encoding_ = UTF8;

bool has_data_ = false;

const char* syscall_ = nullptr;

// Typically, the content of buffer_ is something like a file name, so

// something around 64 bytes should be enough.

FSReqBuffer buffer_;

DISALLOW_COPY_AND_ASSIGN(FSReqBase);

public:

FSReqWrap(Environment* env, Local<Object> req)

: FSReqBase(env, req, AsyncWrap::PROVIDER_FSREQWRAP) { }

void Reject(Local<Value> reject) override;

void Resolve(Local<Value> value) override;

void ResolveStat(const uv_stat_t* stat) override;

void SetReturnValue(const FunctionCallbackInfo<Value>& args) override;

private:

DISALLOW_COPY_AND_ASSIGN(FSReqWrap);

public:

explicit FSReqPromise(Environment* env)

: FSReqBase(env,

env->fsreqpromise_constructor_template()

->NewInstance(env->context()).ToLocalChecked(),

AsyncWrap::PROVIDER_FSREQPROMISE),

stats_field_array_(env->isolate(), env->kFsStatsFieldsLength) {

auto resolver = Promise::Resolver::New(env->context()).ToLocalChecked();

object()->Set(env->context(), env->promise_string(),

resolver).FromJust();

}

~FSReqPromise() override {

// Validate that the promise was explicitly resolved or rejected.

CHECK(finished_);

}

void Reject(Local<Value> reject) override {

finished_ = true;

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

InternalCallbackScope callback_scope(this);

Local<Value> value =

object()->Get(env()->context(),

env()->promise_string()).ToLocalChecked();

Local<Promise::Resolver> resolver = value.As<Promise::Resolver>();

resolver->Reject(env()->context(), reject).FromJust();

}

void Resolve(Local<Value> value) override {

finished_ = true;

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

InternalCallbackScope callback_scope(this);

Local<Value> val =

object()->Get(env()->context(),

env()->promise_string()).ToLocalChecked();

Local<Promise::Resolver> resolver = val.As<Promise::Resolver>();

resolver->Resolve(env()->context(), value).FromJust();

}

void ResolveStat(const uv_stat_t* stat) override {

node::FillStatsArray(&stats_field_array_, stat);

Resolve(stats_field_array_.GetJSArray());

}

void SetReturnValue(const FunctionCallbackInfo<Value>& args) override {

Local<Value> val =

object()->Get(env()->context(),

env()->promise_string()).ToLocalChecked();

Local<Promise::Resolver> resolver = val.As<Promise::Resolver>();

args.GetReturnValue().Set(resolver->GetPromise());

}

private:

bool finished_ = false;

AliasedBuffer<NativeT, V8T> stats_field_array_;

DISALLOW_COPY_AND_ASSIGN(FSReqPromise);

public:

FSReqAfterScope(FSReqBase* wrap, uv_fs_t* req);

~FSReqAfterScope();

bool Proceed();

void Reject(uv_fs_t* req);

private:

FSReqBase* wrap_ = nullptr;

uv_fs_t* req_ = nullptr;

HandleScope handle_scope_;

Context::Scope context_scope_;

public:

FileHandleReadWrap(FileHandle* handle, v8::Local<v8::Object> obj);

static inline FileHandleReadWrap* from_req(uv_fs_t* req) {

return static_cast<FileHandleReadWrap*>(ReqWrap::from_req(req));

}

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

private:

FileHandle* file_handle_;

uv_buf_t buffer_;

friend class FileHandle;

public:

FileHandle(Environment* env,

int fd,

v8::Local<v8::Object> obj = v8::Local<v8::Object>());

virtual ~FileHandle();

static void New(const v8::FunctionCallbackInfo<v8::Value>& args);

int fd() const { return fd_; }

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

// Will asynchronously close the FD and return a Promise that will

// be resolved once closing is complete.

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

// Releases ownership of the FD.

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

// StreamBase interface:

int ReadStart() override;

int ReadStop() override;

bool IsAlive() override { return !closed_; }

bool IsClosing() override { return closing_; }

AsyncWrap* GetAsyncWrap() override { return this; }

// In the case of file streams, shutting down corresponds to closing.

ShutdownWrap* CreateShutdownWrap(v8::Local<v8::Object> object) override;

int DoShutdown(ShutdownWrap* req_wrap) override;

int DoWrite(WriteWrap* w,

uv_buf_t* bufs,

size_t count,

uv_stream_t* send_handle) override {

return UV_ENOSYS; // Not implemented (yet).

}

private:

// Synchronous close that emits a warning

void Close();

void AfterClose();

class CloseReq : public ReqWrap<uv_fs_t> {

public:

CloseReq(Environment* env,

Local<Promise> promise,

Local<Value> ref)

: ReqWrap(env,

env->fdclose_constructor_template()

->NewInstance(env->context()).ToLocalChecked(),

AsyncWrap::PROVIDER_FILEHANDLECLOSEREQ) {

promise_.Reset(env->isolate(), promise);

ref_.Reset(env->isolate(), ref);

}

~CloseReq() {

uv_fs_req_cleanup(req());

promise_.Reset();

ref_.Reset();

}

FileHandle* file_handle();

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

void Resolve();

void Reject(Local<Value> reason);

private:

Persistent<Promise> promise_;

Persistent<Value> ref_;

};

// Asynchronous close

inline MaybeLocal<Promise> ClosePromise();

int fd_;

bool closing_ = false;

bool closed_ = false;

int64_t read_offset_ = -1;

int64_t read_length_ = -1;

bool reading_ = false;

std::unique_ptr<FileHandleReadWrap> current_read_ = nullptr;

DISALLOW_COPY_AND_ASSIGN(FileHandle);