#include "node.h"

#include "node_file.h"

#include "node_buffer.h"

#include "node_internals.h"

#include "node_stat_watcher.h"

#include "env.h"

#include "env-inl.h"

#include "req-wrap.h"

#include "req-wrap-inl.h"

#include "string_bytes.h"

#include "util.h"

#include <fcntl.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <string.h>

#include <errno.h>

#include <limits.h>

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

# include <io.h>

#endif

#include <vector>

namespace node {

using v8::Array;

using v8::Context;

using v8::EscapableHandleScope;

using v8::Function;

using v8::FunctionCallbackInfo;

using v8::FunctionTemplate;

using v8::Handle;

using v8::HandleScope;

using v8::Integer;

using v8::Local;

using v8::Number;

using v8::Object;

using v8::String;

using v8::Value;

#ifndef MIN

# define MIN(a, b) ((a) < (b) ? (a) : (b))

#endif

#define TYPE_ERROR(msg) env->ThrowTypeError(msg)

#define THROW_BAD_ARGS TYPE_ERROR("Bad argument")

#define GET_OFFSET(a) ((a)->IsNumber() ? (a)->IntegerValue() : -1)

class FSReqWrap: public ReqWrap<uv_fs_t> {

public:

enum Ownership { COPY, MOVE };

inline static FSReqWrap* New(Environment* env,

Local<Object> req,

const char* syscall,

const char* data = nullptr,

Ownership ownership = COPY);

inline void Dispose();

void ReleaseEarly() {

if (data_ != inline_data()) {

delete[] data_;

data_ = nullptr;

}

}

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

const char* data() const { return data_; }

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

private:

FSReqWrap(Environment* env,

Local<Object> req,

const char* syscall,

const char* data)

: ReqWrap(env, req, AsyncWrap::PROVIDER_FSREQWRAP),

syscall_(syscall),

data_(data) {

Wrap(object(), this);

}

~FSReqWrap() { ReleaseEarly(); }

void* operator new(size_t size) = delete;

void* operator new(size_t size, char* storage) { return storage; }

char* inline_data() { return reinterpret_cast<char*>(this + 1); }

const char* syscall_;

const char* data_;

DISALLOW_COPY_AND_ASSIGN(FSReqWrap);

};

FSReqWrap* FSReqWrap::New(Environment* env,

Local<Object> req,

const char* syscall,

const char* data,

Ownership ownership) {

const bool copy = (data != nullptr && ownership == COPY);

const size_t size = copy ? 1 + strlen(data) : 0;

FSReqWrap* that;

char* const storage = new char[sizeof(*that) + size];

that = new(storage) FSReqWrap(env, req, syscall, data);

if (copy)

that->data_ = static_cast<char*>(memcpy(that->inline_data(), data, size));

return that;

}

void FSReqWrap::Dispose() {

this->~FSReqWrap();

delete[] reinterpret_cast<char*>(this);

}

static void NewFSReqWrap(const FunctionCallbackInfo<Value>& args) {

CHECK(args.IsConstructCall());

}

static inline bool IsInt64(double x) {

return x == static_cast<double>(static_cast<int64_t>(x));

}

static void After(uv_fs_t *req) {

FSReqWrap* req_wrap = static_cast<FSReqWrap*>(req->data);

CHECK_EQ(&req_wrap->req_, req);

req_wrap->ReleaseEarly(); // Free memory that's no longer used now.

Environment* env = req_wrap->env();

HandleScope handle_scope(env->isolate());

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

// there is always at least one argument. "error"

int argc = 1;

// Allocate space for two args. We may only use one depending on the case.

// (Feel free to increase this if you need more)

Local<Value> argv[2];

if (req->result < 0) {

// An error happened.

argv[0] = UVException(env->isolate(),

req->result,

req_wrap->syscall(),

nullptr,

req->path,

req_wrap->data());

} else {

// error value is empty or null for non-error.

argv[0] = Null(env->isolate());

// All have at least two args now.

argc = 2;

switch (req->fs_type) {

// These all have no data to pass.

case UV_FS_ACCESS:

case UV_FS_CLOSE:

case UV_FS_RENAME:

case UV_FS_UNLINK:

case UV_FS_RMDIR:

case UV_FS_MKDIR:

case UV_FS_FTRUNCATE:

case UV_FS_FSYNC:

case UV_FS_FDATASYNC:

case UV_FS_LINK:

case UV_FS_SYMLINK:

case UV_FS_CHMOD:

case UV_FS_FCHMOD:

case UV_FS_CHOWN:

case UV_FS_FCHOWN:

// These, however, don't.

argc = 1;

break;

case UV_FS_UTIME:

case UV_FS_FUTIME:

argc = 0;

break;

case UV_FS_OPEN:

argv[1] = Integer::New(env->isolate(), req->result);

break;

case UV_FS_WRITE:

argv[1] = Integer::New(env->isolate(), req->result);

break;

case UV_FS_STAT:

case UV_FS_LSTAT:

case UV_FS_FSTAT:

argv[1] = BuildStatsObject(env,

static_cast<const uv_stat_t*>(req->ptr));

break;

case UV_FS_READLINK:

argv[1] = String::NewFromUtf8(env->isolate(),

static_cast<const char*>(req->ptr));

break;

case UV_FS_READ:

// Buffer interface

argv[1] = Integer::New(env->isolate(), req->result);

break;

case UV_FS_SCANDIR:

{

int r;

Local<Array> names = Array::New(env->isolate(), 0);

for (int i = 0; ; i++) {

uv_dirent_t ent;

r = uv_fs_scandir_next(req, &ent);

if (r == UV_EOF)

break;

if (r != 0) {

argv[0] = UVException(r,

nullptr,

req_wrap->syscall(),

static_cast<const char*>(req->path));

break;

}

Local<String> name = String::NewFromUtf8(env->isolate(),

ent.name);

names->Set(i, name);

}

argv[1] = names;

}

break;

default:

CHECK(0 && "Unhandled eio response");

}

}

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

uv_fs_req_cleanup(&req_wrap->req_);

req_wrap->Dispose();

}

// This struct is only used on sync fs calls.

// For async calls FSReqWrap is used.

struct fs_req_wrap {

fs_req_wrap() {}

~fs_req_wrap() { uv_fs_req_cleanup(&req); }

uv_fs_t req;

DISALLOW_COPY_AND_ASSIGN(fs_req_wrap);

};

#define ASYNC_DEST_CALL(func, req, dest, ...) \

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

CHECK(req->IsObject()); \

FSReqWrap* req_wrap = FSReqWrap::New(env, req.As<Object>(), #func, dest); \

int err = uv_fs_ ## func(env->event_loop(), \

&req_wrap->req_, \

__VA_ARGS__, \

After); \

req_wrap->Dispatched(); \

if (err < 0) { \

uv_fs_t* uv_req = &req_wrap->req_; \

uv_req->result = err; \

uv_req->path = nullptr; \

After(uv_req); \

} \

args.GetReturnValue().Set(req_wrap->persistent());

#define ASYNC_CALL(func, req, ...) \

ASYNC_DEST_CALL(func, req, nullptr, __VA_ARGS__) \

#define SYNC_DEST_CALL(func, path, dest, ...) \

fs_req_wrap req_wrap; \

env->PrintSyncTrace(); \

int err = uv_fs_ ## func(env->event_loop(), \

&req_wrap.req, \

__VA_ARGS__, \

nullptr); \

if (err < 0) { \

return env->ThrowUVException(err, #func, nullptr, path, dest); \

} \

#define SYNC_CALL(func, path, ...) \

SYNC_DEST_CALL(func, path, nullptr, __VA_ARGS__) \

#define SYNC_REQ req_wrap.req

#define SYNC_RESULT err

static void Access(const FunctionCallbackInfo<Value>& args) {

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

HandleScope scope(env->isolate());

if (args.Length() < 2)

return THROW_BAD_ARGS;

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

if (!args[1]->IsInt32())

return TYPE_ERROR("mode must be an integer");

node::Utf8Value path(env->isolate(), args[0]);

int mode = static_cast<int>(args[1]->Int32Value());

if (args[2]->IsObject()) {

ASYNC_CALL(access, args[2], *path, mode);

} else {

SYNC_CALL(access, *path, *path, mode);

}

}

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

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

if (args.Length() < 1 || !args[0]->IsInt32()) {

return THROW_BAD_ARGS;

}

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

if (args[1]->IsObject()) {

ASYNC_CALL(close, args[1], fd)

} else {

SYNC_CALL(close, 0, fd)

}

}

Local<Value> BuildStatsObject(Environment* env, const uv_stat_t* s) {

// If you hit this assertion, you forgot to enter the v8::Context first.

CHECK_EQ(env->context(), env->isolate()->GetCurrentContext());

EscapableHandleScope handle_scope(env->isolate());

// The code below is very nasty-looking but it prevents a segmentation fault

// when people run JS code like the snippet below. It's apparently more

// common than you would expect, several people have reported this crash...

//

// function crash() {

// fs.statSync('.');

// crash();

// }

//

// We need to check the return value of Integer::New() and Date::New()

// and make sure that we bail out when V8 returns an empty handle.

// Integers.

#define X(name) \

Local<Value> name = Integer::New(env->isolate(), s->st_##name); \

if (name.IsEmpty()) \

return handle_scope.Escape(Local<Object>()); \

X(dev)

X(mode)

X(nlink)

X(uid)

X(gid)

X(rdev)

# if defined(__POSIX__)

X(blksize)

# else

Local<Value> blksize = Undefined(env->isolate());

# endif

#undef X

// Numbers.

#define X(name) \

Local<Value> name = Number::New(env->isolate(), \

static_cast<double>(s->st_##name)); \

if (name.IsEmpty()) \

return handle_scope.Escape(Local<Object>()); \

X(ino)

X(size)

# if defined(__POSIX__)

X(blocks)

# else

Local<Value> blocks = Undefined(env->isolate());

# endif

#undef X

// Dates.

#define X(name) \

Local<Value> name##_msec = \

Number::New(env->isolate(), \

(static_cast<double>(s->st_##name.tv_sec) * 1000) + \

(static_cast<double>(s->st_##name.tv_nsec / 1000000))); \

\

if (name##_msec.IsEmpty()) \

return handle_scope.Escape(Local<Object>()); \

X(atim)

X(mtim)

X(ctim)

X(birthtim)

#undef X

// Pass stats as the first argument, this is the object we are modifying.

Local<Value> argv[] = {

dev,

mode,

nlink,

uid,

gid,

rdev,

blksize,

ino,

size,

blocks,

atim_msec,

mtim_msec,

ctim_msec,

birthtim_msec

};

// Call out to JavaScript to create the stats object.

Local<Value> stats =

env->fs_stats_constructor_function()->NewInstance(ARRAY_SIZE(argv), argv);

if (stats.IsEmpty())

return handle_scope.Escape(Local<Object>());

return handle_scope.Escape(stats);

}

// Used to speed up module loading. Returns the contents of the file as

// a string or undefined when the file cannot be opened. The speedup

// comes from not creating Error objects on failure.

static void InternalModuleReadFile(const FunctionCallbackInfo<Value>& args) {

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

CHECK(args[0]->IsString());

node::Utf8Value path(env->isolate(), args[0]);

FILE* const stream = fopen(*path, "rb");

if (stream == nullptr) {

return;

}

std::vector<char> chars;

while (!ferror(stream)) {

const size_t kBlockSize = 32 << 10;

const size_t start = chars.size();

chars.resize(start + kBlockSize);

const size_t numchars = fread(&chars[start], 1, kBlockSize, stream);

if (numchars < kBlockSize) {

chars.resize(start + numchars);

}

if (numchars == 0) {

break;

}

}

CHECK_EQ(false, ferror(stream));

CHECK_EQ(0, fclose(stream));

size_t start = 0;

if (chars.size() >= 3 && 0 == memcmp(&chars[0], "\xEF\xBB\xBF", 3)) {

start = 3; // Skip UTF-8 BOM.

}

Local<String> chars_string =

String::NewFromUtf8(env->isolate(),

&chars[start],

String::kNormalString,

chars.size() - start);

args.GetReturnValue().Set(chars_string);

}

// Used to speed up module loading. Returns 0 if the path refers to

// a file, 1 when it's a directory or < 0 on error (usually -ENOENT.)

// The speedup comes from not creating thousands of Stat and Error objects.

static void InternalModuleStat(const FunctionCallbackInfo<Value>& args) {

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

CHECK(args[0]->IsString());

node::Utf8Value path(env->isolate(), args[0]);

uv_fs_t req;

int rc = uv_fs_stat(env->event_loop(), &req, *path, nullptr);

if (rc == 0) {

const uv_stat_t* const s = static_cast<const uv_stat_t*>(req.ptr);

rc = !!(s->st_mode & S_IFDIR);

}

uv_fs_req_cleanup(&req);

args.GetReturnValue().Set(rc);

}

static void Stat(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1)

return TYPE_ERROR("path required");

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

node::Utf8Value path(env->isolate(), args[0]);

if (args[1]->IsObject()) {

ASYNC_CALL(stat, args[1], *path)

} else {

SYNC_CALL(stat, *path, *path)

args.GetReturnValue().Set(

BuildStatsObject(env, static_cast<const uv_stat_t*>(SYNC_REQ.ptr)));

}

}

static void LStat(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1)

return TYPE_ERROR("path required");

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

node::Utf8Value path(env->isolate(), args[0]);

if (args[1]->IsObject()) {

ASYNC_CALL(lstat, args[1], *path)

} else {

SYNC_CALL(lstat, *path, *path)

args.GetReturnValue().Set(

BuildStatsObject(env, static_cast<const uv_stat_t*>(SYNC_REQ.ptr)));

}

}

static void FStat(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1 || !args[0]->IsInt32()) {

return THROW_BAD_ARGS;

}

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

if (args[1]->IsObject()) {

ASYNC_CALL(fstat, args[1], fd)

} else {

SYNC_CALL(fstat, 0, fd)

args.GetReturnValue().Set(

BuildStatsObject(env, static_cast<const uv_stat_t*>(SYNC_REQ.ptr)));

}

}

static void Symlink(const FunctionCallbackInfo<Value>& args) {

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

int len = args.Length();

if (len < 1)

return TYPE_ERROR("dest path required");

if (len < 2)

return TYPE_ERROR("src path required");

if (!args[0]->IsString())

return TYPE_ERROR("dest path must be a string");

if (!args[1]->IsString())

return TYPE_ERROR("src path must be a string");

node::Utf8Value dest(env->isolate(), args[0]);

node::Utf8Value path(env->isolate(), args[1]);

int flags = 0;

if (args[2]->IsString()) {

node::Utf8Value mode(env->isolate(), args[2]);

if (strcmp(*mode, "dir") == 0) {

flags |= UV_FS_SYMLINK_DIR;

} else if (strcmp(*mode, "junction") == 0) {

flags |= UV_FS_SYMLINK_JUNCTION;

} else if (strcmp(*mode, "file") != 0) {

return env->ThrowError("Unknown symlink type");

}

}

if (args[3]->IsObject()) {

ASYNC_DEST_CALL(symlink, args[3], *path, *dest, *path, flags)

} else {

SYNC_DEST_CALL(symlink, *dest, *path, *dest, *path, flags)

}

}

static void Link(const FunctionCallbackInfo<Value>& args) {

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

int len = args.Length();

if (len < 1)

return TYPE_ERROR("dest path required");

if (len < 2)

return TYPE_ERROR("src path required");

if (!args[0]->IsString())

return TYPE_ERROR("dest path must be a string");

if (!args[1]->IsString())

return TYPE_ERROR("src path must be a string");

node::Utf8Value orig_path(env->isolate(), args[0]);

node::Utf8Value new_path(env->isolate(), args[1]);

if (args[2]->IsObject()) {

ASYNC_DEST_CALL(link, args[2], *new_path, *orig_path, *new_path)

} else {

SYNC_DEST_CALL(link, *orig_path, *new_path, *orig_path, *new_path)

}

}

static void ReadLink(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1)

return TYPE_ERROR("path required");

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

node::Utf8Value path(env->isolate(), args[0]);

if (args[1]->IsObject()) {

ASYNC_CALL(readlink, args[1], *path)

} else {

SYNC_CALL(readlink, *path, *path)

const char* link_path = static_cast<const char*>(SYNC_REQ.ptr);

Local<String> rc = String::NewFromUtf8(env->isolate(), link_path);

args.GetReturnValue().Set(rc);

}

}

static void Rename(const FunctionCallbackInfo<Value>& args) {

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

int len = args.Length();

if (len < 1)

return TYPE_ERROR("old path required");

if (len < 2)

return TYPE_ERROR("new path required");

if (!args[0]->IsString())

return TYPE_ERROR("old path must be a string");

if (!args[1]->IsString())

return TYPE_ERROR("new path must be a string");

node::Utf8Value old_path(env->isolate(), args[0]);

node::Utf8Value new_path(env->isolate(), args[1]);

if (args[2]->IsObject()) {

ASYNC_DEST_CALL(rename, args[2], *new_path, *old_path, *new_path)

} else {

SYNC_DEST_CALL(rename, *old_path, *new_path, *old_path, *new_path)

}

}

static void FTruncate(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 2 || !args[0]->IsInt32()) {

return THROW_BAD_ARGS;

}

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

// FIXME(bnoordhuis) It's questionable to reject non-ints here but still

// allow implicit coercion from null or undefined to zero. Probably best

// handled in lib/fs.js.

Local<Value> len_v(args[1]);

if (!len_v->IsUndefined() &&

!len_v->IsNull() &&

!IsInt64(len_v->NumberValue())) {

return env->ThrowTypeError("Not an integer");

}

const int64_t len = len_v->IntegerValue();

if (args[2]->IsObject()) {

ASYNC_CALL(ftruncate, args[2], fd, len)

} else {

SYNC_CALL(ftruncate, 0, fd, len)

}

}

static void Fdatasync(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1 || !args[0]->IsInt32()) {

return THROW_BAD_ARGS;

}

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

if (args[1]->IsObject()) {

ASYNC_CALL(fdatasync, args[1], fd)

} else {

SYNC_CALL(fdatasync, 0, fd)

}

}

static void Fsync(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1 || !args[0]->IsInt32()) {

return THROW_BAD_ARGS;

}

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

if (args[1]->IsObject()) {

ASYNC_CALL(fsync, args[1], fd)

} else {

SYNC_CALL(fsync, 0, fd)

}

}

static void Unlink(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1)

return TYPE_ERROR("path required");

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

node::Utf8Value path(env->isolate(), args[0]);

if (args[1]->IsObject()) {

ASYNC_CALL(unlink, args[1], *path)

} else {

SYNC_CALL(unlink, *path, *path)

}

}

static void RMDir(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1)

return TYPE_ERROR("path required");

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

node::Utf8Value path(env->isolate(), args[0]);

if (args[1]->IsObject()) {

ASYNC_CALL(rmdir, args[1], *path)

} else {

SYNC_CALL(rmdir, *path, *path)

}

}

static void MKDir(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 2 || !args[0]->IsString() || !args[1]->IsInt32()) {

return THROW_BAD_ARGS;

}

node::Utf8Value path(env->isolate(), args[0]);

int mode = static_cast<int>(args[1]->Int32Value());

if (args[2]->IsObject()) {

ASYNC_CALL(mkdir, args[2], *path, mode)

} else {

SYNC_CALL(mkdir, *path, *path, mode)

}

}

static void ReadDir(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 1)

return TYPE_ERROR("path required");

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

node::Utf8Value path(env->isolate(), args[0]);

if (args[1]->IsObject()) {

ASYNC_CALL(scandir, args[1], *path, 0 /*flags*/)

} else {

SYNC_CALL(scandir, *path, *path, 0 /*flags*/)

CHECK_GE(SYNC_REQ.result, 0);

int r;

Local<Array> names = Array::New(env->isolate(), 0);

for (int i = 0; ; i++) {

uv_dirent_t ent;

r = uv_fs_scandir_next(&SYNC_REQ, &ent);

if (r == UV_EOF)

break;

if (r != 0)

return env->ThrowUVException(r, "readdir", "", *path);

Local<String> name = String::NewFromUtf8(env->isolate(),

ent.name);

names->Set(i, name);

}

args.GetReturnValue().Set(names);

}

}

static void Open(const FunctionCallbackInfo<Value>& args) {

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

int len = args.Length();

if (len < 1)

return TYPE_ERROR("path required");

if (len < 2)

return TYPE_ERROR("flags required");

if (len < 3)

return TYPE_ERROR("mode required");

if (!args[0]->IsString())

return TYPE_ERROR("path must be a string");

if (!args[1]->IsInt32())

return TYPE_ERROR("flags must be an int");

if (!args[2]->IsInt32())

return TYPE_ERROR("mode must be an int");

node::Utf8Value path(env->isolate(), args[0]);

int flags = args[1]->Int32Value();

int mode = static_cast<int>(args[2]->Int32Value());

if (args[3]->IsObject()) {

ASYNC_CALL(open, args[3], *path, flags, mode)

} else {

SYNC_CALL(open, *path, *path, flags, mode)

args.GetReturnValue().Set(SYNC_RESULT);

}

}

// Wrapper for write(2).

//

// bytesWritten = write(fd, buffer, offset, length, position, callback)

// 0 fd integer. file descriptor

// 1 buffer the data to write

// 2 offset where in the buffer to start from

// 3 length how much to write

// 4 position if integer, position to write at in the file.

// if null, write from the current position

static void WriteBuffer(const FunctionCallbackInfo<Value>& args) {

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

if (!args[0]->IsInt32())

return env->ThrowTypeError("First argument must be file descriptor");

CHECK(Buffer::HasInstance(args[1]));

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

Local<Object> obj = args[1].As<Object>();

const char* buf = Buffer::Data(obj);

size_t buffer_length = Buffer::Length(obj);

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

size_t len = args[3]->Uint32Value();

int64_t pos = GET_OFFSET(args[4]);

Local<Value> req = args[5];

if (off > buffer_length)

return env->ThrowRangeError("offset out of bounds");

if (len > buffer_length)

return env->ThrowRangeError("length out of bounds");

if (off + len < off)

return env->ThrowRangeError("off + len overflow");

if (!Buffer::IsWithinBounds(off, len, buffer_length))

return env->ThrowRangeError("off + len > buffer.length");

buf += off;

uv_buf_t uvbuf = uv_buf_init(const_cast<char*>(buf), len);

if (req->IsObject()) {

ASYNC_CALL(write, req, fd, &uvbuf, 1, pos)

return;

}

SYNC_CALL(write, nullptr, fd, &uvbuf, 1, pos)

args.GetReturnValue().Set(SYNC_RESULT);

}

// Wrapper for write(2).

//

// bytesWritten = write(fd, string, position, enc, callback)

// 0 fd integer. file descriptor

// 1 string non-buffer values are converted to strings

// 2 position if integer, position to write at in the file.

// if null, write from the current position

// 3 enc encoding of string

static void WriteString(const FunctionCallbackInfo<Value>& args) {

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

if (!args[0]->IsInt32())

return env->ThrowTypeError("First argument must be file descriptor");

Local<Value> req;

Local<Value> string = args[1];

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

char* buf = nullptr;

int64_t pos;

size_t len;

FSReqWrap::Ownership ownership = FSReqWrap::COPY;

// will assign buf and len if string was external

if (!StringBytes::GetExternalParts(env->isolate(),

string,

const_cast<const char**>(&buf),

&len)) {

enum encoding enc = ParseEncoding(env->isolate(), args[3], UTF8);

len = StringBytes::StorageSize(env->isolate(), string, enc);

buf = new char[len];

// StorageSize may return too large a char, so correct the actual length

// by the write size

len = StringBytes::Write(env->isolate(), buf, len, args[1], enc);

ownership = FSReqWrap::MOVE;

}

pos = GET_OFFSET(args[2]);

req = args[4];

uv_buf_t uvbuf = uv_buf_init(const_cast<char*>(buf), len);

if (!req->IsObject()) {

// SYNC_CALL returns on error. Make sure to always free the memory.

struct Delete {

inline explicit Delete(char* pointer) : pointer_(pointer) {}

inline ~Delete() { delete[] pointer_; }

char* const pointer_;

};

Delete delete_on_return(ownership == FSReqWrap::MOVE ? buf : nullptr);

SYNC_CALL(write, nullptr, fd, &uvbuf, 1, pos)

return args.GetReturnValue().Set(SYNC_RESULT);

}

FSReqWrap* req_wrap =

FSReqWrap::New(env, req.As<Object>(), "write", buf, ownership);

int err = uv_fs_write(env->event_loop(),

&req_wrap->req_,

fd,

&uvbuf,

1,

pos,

After);

req_wrap->Dispatched();

if (err < 0) {

uv_fs_t* uv_req = &req_wrap->req_;

uv_req->result = err;

uv_req->path = nullptr;

After(uv_req);

}

return args.GetReturnValue().Set(req_wrap->persistent());

}

/*

* Wrapper for read(2).

*

* bytesRead = fs.read(fd, buffer, offset, length, position)

*

* 0 fd integer. file descriptor

* 1 buffer instance of Buffer

* 2 offset integer. offset to start reading into inside buffer

* 3 length integer. length to read

* 4 position file position - null for current position

*

*/

static void Read(const FunctionCallbackInfo<Value>& args) {

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

if (args.Length() < 2 || !args[0]->IsInt32()) {

return THROW_BAD_ARGS;

}

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

Local<Value> req;

size_t len;

int64_t pos;

char * buf = nullptr;

if (!Buffer::HasInstance(args[1])) {

return env->ThrowError("Second argument needs to be a buffer");

}

Local<Object> buffer_obj = args[1]->ToObject(env->isolate());

char *buffer_data = Buffer::Data(buffer_obj);

size_t buffer_length = Buffer::Length(buffer_obj);

size_t off = args[2]->Int32Value();

if (off >= buffer_length) {

return env->ThrowError("Offset is out of bounds");

}