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Copy pathnode_buffer.cc
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1877 lines (1577 loc) · 62.8 KB
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// 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_buffer.h"
#include "node.h"
#include "node_blob.h"
#include "node_debug.h"
#include "node_errors.h"
#include "node_external_reference.h"
#include "node_i18n.h"
#include "node_internals.h"
#include "env-inl.h"
#include "simdutf.h"
#include "string_bytes.h"
#include "util-inl.h"
#include "v8-fast-api-calls.h"
#include "v8.h"
#include <stdint.h>
#include <climits>
#include <cstring>
#include "nbytes.h"
#define THROW_AND_RETURN_UNLESS_BUFFER(env, obj) \
THROW_AND_RETURN_IF_NOT_BUFFER(env, obj, "argument") \
#define THROW_AND_RETURN_IF_OOB(r) \
do { \
Maybe<bool> m = (r); \
if (m.IsNothing()) return; \
if (!m.FromJust()) \
return node::THROW_ERR_OUT_OF_RANGE(env, "Index out of range"); \
} while (0) \
namespace node {
namespace Buffer {
using v8::ArrayBuffer;
using v8::ArrayBufferView;
using v8::BackingStore;
using v8::BackingStoreInitializationMode;
using v8::BackingStoreOnFailureMode;
using v8::CFunction;
using v8::Context;
using v8::EscapableHandleScope;
using v8::FastApiCallbackOptions;
using v8::FastOneByteString;
using v8::FunctionCallbackInfo;
using v8::Global;
using v8::HandleScope;
using v8::Int32;
using v8::Integer;
using v8::Isolate;
using v8::Just;
using v8::Local;
using v8::Maybe;
using v8::MaybeLocal;
using v8::Nothing;
using v8::Number;
using v8::Object;
using v8::SharedArrayBuffer;
using v8::String;
using v8::Uint32;
using v8::Uint8Array;
using v8::Value;
namespace {
class CallbackInfo : public Cleanable {
public:
static inline Local<ArrayBuffer> CreateTrackedArrayBuffer(
Environment* env,
char* data,
size_t length,
FreeCallback callback,
void* hint);
CallbackInfo(const CallbackInfo&) = delete;
CallbackInfo& operator=(const CallbackInfo&) = delete;
private:
void Clean() override;
inline void OnBackingStoreFree();
inline void CallAndResetCallback();
inline CallbackInfo(Environment* env,
FreeCallback callback,
char* data,
void* hint);
Global<ArrayBuffer> persistent_;
Mutex mutex_; // Protects callback_.
FreeCallback callback_;
char* const data_;
void* const hint_;
Environment* const env_;
};
Local<ArrayBuffer> CallbackInfo::CreateTrackedArrayBuffer(
Environment* env,
char* data,
size_t length,
FreeCallback callback,
void* hint) {
CHECK_NOT_NULL(callback);
CHECK_IMPLIES(data == nullptr, length == 0);
CallbackInfo* self = new CallbackInfo(env, callback, data, hint);
std::unique_ptr<BackingStore> bs =
ArrayBuffer::NewBackingStore(data, length, [](void*, size_t, void* arg) {
static_cast<CallbackInfo*>(arg)->OnBackingStoreFree();
}, self);
Local<ArrayBuffer> ab = ArrayBuffer::New(env->isolate(), std::move(bs));
// V8 simply ignores the BackingStore deleter callback if data == nullptr,
// but our API contract requires it being called.
if (data == nullptr) {
ab->Detach(Local<Value>()).Check();
self->OnBackingStoreFree(); // This calls `callback` asynchronously.
} else {
// Store the ArrayBuffer so that we can detach it later.
self->persistent_.Reset(env->isolate(), ab);
self->persistent_.SetWeak();
}
return ab;
}
CallbackInfo::CallbackInfo(Environment* env,
FreeCallback callback,
char* data,
void* hint)
: callback_(callback),
data_(data),
hint_(hint),
env_(env) {
env->cleanable_queue()->PushFront(this);
env->external_memory_accounter()->Increase(env->isolate(), sizeof(*this));
}
void CallbackInfo::Clean() {
{
HandleScope handle_scope(env_->isolate());
Local<ArrayBuffer> ab = persistent_.Get(env_->isolate());
if (!ab.IsEmpty() && ab->IsDetachable()) {
ab->Detach(Local<Value>()).Check();
persistent_.Reset();
}
}
// Call the callback in this case, but don't delete `this` yet because the
// BackingStore deleter callback will do so later.
CallAndResetCallback();
}
void CallbackInfo::CallAndResetCallback() {
FreeCallback callback;
{
Mutex::ScopedLock lock(mutex_);
callback = callback_;
callback_ = nullptr;
}
if (callback != nullptr) {
// Clean up all Environment-related state and run the callback.
cleanable_queue_.Remove();
env_->external_memory_accounter()->Decrease(env_->isolate(), sizeof(*this));
callback(data_, hint_);
}
}
void CallbackInfo::OnBackingStoreFree() {
// This method should always release the memory for `this`.
std::unique_ptr<CallbackInfo> self { this };
Mutex::ScopedLock lock(mutex_);
// If callback_ == nullptr, that means that the callback has already run from
// the cleanup hook, and there is nothing left to do here besides to clean
// up the memory involved. In particular, the underlying `Environment` may
// be gone at this point, so don’t attempt to call SetImmediateThreadsafe().
if (callback_ == nullptr) return;
env_->SetImmediateThreadsafe([self = std::move(self)](Environment* env) {
CHECK_EQ(self->env_, env); // Consistency check.
self->CallAndResetCallback();
});
}
// Parse index for external array data. An empty Maybe indicates
// a pending exception. `false` indicates that the index is out-of-bounds.
inline MUST_USE_RESULT Maybe<bool> ParseArrayIndex(Environment* env,
Local<Value> arg,
size_t def,
size_t* ret) {
if (arg->IsUndefined()) {
*ret = def;
return Just(true);
}
int64_t tmp_i;
if (!arg->IntegerValue(env->context()).To(&tmp_i))
return Nothing<bool>();
if (tmp_i < 0)
return Just(false);
// Check that the result fits in a size_t.
// coverity[pointless_expression]
if (static_cast<uint64_t>(tmp_i) > std::numeric_limits<size_t>::max())
return Just(false);
*ret = static_cast<size_t>(tmp_i);
return Just(true);
}
} // anonymous namespace
// Buffer methods
bool HasInstance(Local<Value> val) {
return val->IsArrayBufferView();
}
bool HasInstance(Local<Object> obj) {
return obj->IsArrayBufferView();
}
char* Data(Local<Value> val) {
CHECK(val->IsArrayBufferView());
Local<ArrayBufferView> ui = val.As<ArrayBufferView>();
return static_cast<char*>(ui->Buffer()->Data()) + ui->ByteOffset();
}
char* Data(Local<Object> obj) {
return Data(obj.As<Value>());
}
size_t Length(Local<Value> val) {
CHECK(val->IsArrayBufferView());
Local<ArrayBufferView> ui = val.As<ArrayBufferView>();
return ui->ByteLength();
}
size_t Length(Local<Object> obj) {
CHECK(obj->IsArrayBufferView());
Local<ArrayBufferView> ui = obj.As<ArrayBufferView>();
return ui->ByteLength();
}
MaybeLocal<Uint8Array> New(Environment* env,
Local<ArrayBuffer> ab,
size_t byte_offset,
size_t length) {
CHECK(!env->buffer_prototype_object().IsEmpty());
Local<Uint8Array> ui = Uint8Array::New(ab, byte_offset, length);
if (ui->SetPrototypeV2(env->context(), env->buffer_prototype_object())
.IsNothing()) {
return MaybeLocal<Uint8Array>();
}
return ui;
}
MaybeLocal<Uint8Array> New(Isolate* isolate,
Local<ArrayBuffer> ab,
size_t byte_offset,
size_t length) {
Environment* env = Environment::GetCurrent(isolate);
if (env == nullptr) {
THROW_ERR_BUFFER_CONTEXT_NOT_AVAILABLE(isolate);
return MaybeLocal<Uint8Array>();
}
return New(env, ab, byte_offset, length);
}
MaybeLocal<Object> New(Isolate* isolate,
Local<String> string,
enum encoding enc) {
EscapableHandleScope scope(isolate);
size_t length;
if (!StringBytes::Size(isolate, string, enc).To(&length)) return {};
size_t actual = 0;
std::unique_ptr<BackingStore> store;
if (length > 0) {
store = ArrayBuffer::NewBackingStore(
isolate,
length,
BackingStoreInitializationMode::kZeroInitialized,
BackingStoreOnFailureMode::kReturnNull);
if (!store) [[unlikely]] {
THROW_ERR_MEMORY_ALLOCATION_FAILED(isolate);
return {};
}
actual = StringBytes::Write(
isolate,
static_cast<char*>(store->Data()),
length,
string,
enc);
CHECK(actual <= length);
if (actual > 0) [[likely]] {
if (actual < length) {
std::unique_ptr<BackingStore> old_store = std::move(store);
store = ArrayBuffer::NewBackingStore(
isolate,
actual,
BackingStoreInitializationMode::kUninitialized,
BackingStoreOnFailureMode::kReturnNull);
if (!store) [[unlikely]] {
THROW_ERR_MEMORY_ALLOCATION_FAILED(isolate);
return {};
}
memcpy(store->Data(), old_store->Data(), actual);
}
Local<ArrayBuffer> buf = ArrayBuffer::New(isolate, std::move(store));
Local<Object> obj;
if (!New(isolate, buf, 0, actual).ToLocal(&obj)) [[unlikely]] {
return {};
}
return scope.Escape(obj);
}
}
return scope.EscapeMaybe(New(isolate, 0));
}
MaybeLocal<Object> New(Isolate* isolate, size_t length) {
EscapableHandleScope handle_scope(isolate);
Local<Object> obj;
Environment* env = Environment::GetCurrent(isolate);
if (env == nullptr) {
THROW_ERR_BUFFER_CONTEXT_NOT_AVAILABLE(isolate);
return MaybeLocal<Object>();
}
if (Buffer::New(env, length).ToLocal(&obj))
return handle_scope.Escape(obj);
return Local<Object>();
}
MaybeLocal<Object> New(Environment* env, size_t length) {
Isolate* isolate(env->isolate());
EscapableHandleScope scope(isolate);
// V8 currently only allows a maximum Typed Array index of max Smi.
if (length > kMaxLength) {
isolate->ThrowException(ERR_BUFFER_TOO_LARGE(isolate));
return Local<Object>();
}
Local<ArrayBuffer> ab;
{
std::unique_ptr<BackingStore> bs = ArrayBuffer::NewBackingStore(
isolate,
length,
BackingStoreInitializationMode::kUninitialized,
BackingStoreOnFailureMode::kReturnNull);
if (!bs) [[unlikely]] {
THROW_ERR_MEMORY_ALLOCATION_FAILED(isolate);
return {};
}
CHECK(bs);
ab = ArrayBuffer::New(isolate, std::move(bs));
}
MaybeLocal<Object> obj =
New(env, ab, 0, ab->ByteLength())
.FromMaybe(Local<Uint8Array>());
return scope.EscapeMaybe(obj);
}
MaybeLocal<Object> Copy(Isolate* isolate, const char* data, size_t length) {
EscapableHandleScope handle_scope(isolate);
Environment* env = Environment::GetCurrent(isolate);
if (env == nullptr) {
THROW_ERR_BUFFER_CONTEXT_NOT_AVAILABLE(isolate);
return MaybeLocal<Object>();
}
Local<Object> obj;
if (Buffer::Copy(env, data, length).ToLocal(&obj))
return handle_scope.Escape(obj);
return Local<Object>();
}
MaybeLocal<Object> Copy(Environment* env, const char* data, size_t length) {
Isolate* isolate(env->isolate());
EscapableHandleScope scope(isolate);
// V8 currently only allows a maximum Typed Array index of max Smi.
if (length > kMaxLength) {
isolate->ThrowException(ERR_BUFFER_TOO_LARGE(isolate));
return Local<Object>();
}
std::unique_ptr<BackingStore> bs = ArrayBuffer::NewBackingStore(
isolate,
length,
BackingStoreInitializationMode::kUninitialized,
BackingStoreOnFailureMode::kReturnNull);
if (!bs) [[unlikely]] {
THROW_ERR_MEMORY_ALLOCATION_FAILED(isolate);
return {};
}
if (length > 0) memcpy(bs->Data(), data, length);
Local<ArrayBuffer> ab = ArrayBuffer::New(isolate, std::move(bs));
MaybeLocal<Object> obj =
New(env, ab, 0, ab->ByteLength())
.FromMaybe(Local<Uint8Array>());
return scope.EscapeMaybe(obj);
}
MaybeLocal<Object> New(Isolate* isolate,
char* data,
size_t length,
FreeCallback callback,
void* hint) {
EscapableHandleScope handle_scope(isolate);
Environment* env = Environment::GetCurrent(isolate);
if (env == nullptr) {
callback(data, hint);
THROW_ERR_BUFFER_CONTEXT_NOT_AVAILABLE(isolate);
return MaybeLocal<Object>();
}
return handle_scope.EscapeMaybe(
Buffer::New(env, data, length, callback, hint));
}
MaybeLocal<Object> New(Environment* env,
char* data,
size_t length,
FreeCallback callback,
void* hint) {
EscapableHandleScope scope(env->isolate());
if (length > kMaxLength) {
env->isolate()->ThrowException(ERR_BUFFER_TOO_LARGE(env->isolate()));
callback(data, hint);
return Local<Object>();
}
Local<ArrayBuffer> ab =
CallbackInfo::CreateTrackedArrayBuffer(env, data, length, callback, hint);
if (ab->SetPrivate(env->context(),
env->untransferable_object_private_symbol(),
True(env->isolate())).IsNothing()) {
return Local<Object>();
}
MaybeLocal<Uint8Array> maybe_ui = Buffer::New(env, ab, 0, length);
Local<Uint8Array> ui;
if (!maybe_ui.ToLocal(&ui))
return MaybeLocal<Object>();
return scope.Escape(ui);
}
// Warning: This function needs `data` to be allocated with malloc() and not
// necessarily isolate's ArrayBuffer::Allocator.
MaybeLocal<Object> New(Isolate* isolate, char* data, size_t length) {
EscapableHandleScope handle_scope(isolate);
Environment* env = Environment::GetCurrent(isolate);
if (env == nullptr) {
free(data);
THROW_ERR_BUFFER_CONTEXT_NOT_AVAILABLE(isolate);
return MaybeLocal<Object>();
}
Local<Object> obj;
if (Buffer::New(env, data, length).ToLocal(&obj))
return handle_scope.Escape(obj);
return Local<Object>();
}
// The contract for this function is that `data` is allocated with malloc()
// and not necessarily isolate's ArrayBuffer::Allocator.
MaybeLocal<Object> New(Environment* env,
char* data,
size_t length) {
if (length > 0) {
CHECK_NOT_NULL(data);
// V8 currently only allows a maximum Typed Array index of max Smi.
if (length > kMaxLength) {
Isolate* isolate(env->isolate());
isolate->ThrowException(ERR_BUFFER_TOO_LARGE(isolate));
free(data);
return Local<Object>();
}
}
#if defined(V8_ENABLE_SANDBOX)
// When v8 sandbox is enabled, external backing stores are not supported
// since all arraybuffer allocations are expected to be done by the isolate.
// Since this violates the contract of this function, let's free the data and
// throw an error.
free(data);
THROW_ERR_OPERATION_FAILED(
env->isolate(),
"Wrapping external data is not supported when the v8 sandbox is enabled");
return MaybeLocal<Object>();
#else
EscapableHandleScope handle_scope(env->isolate());
auto free_callback = [](void* data, size_t length, void* deleter_data) {
free(data);
};
std::unique_ptr<BackingStore> bs =
ArrayBuffer::NewBackingStore(data, length, free_callback, nullptr);
Local<ArrayBuffer> ab = ArrayBuffer::New(env->isolate(), std::move(bs));
Local<Object> obj;
if (Buffer::New(env, ab, 0, length).ToLocal(&obj))
return handle_scope.Escape(obj);
return Local<Object>();
#endif
}
namespace {
template <encoding encoding>
void StringSlice(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
Isolate* isolate = env->isolate();
THROW_AND_RETURN_UNLESS_BUFFER(env, args[0]);
ArrayBufferViewContents<char> buffer(args[0]);
auto buffer_length = buffer.length();
const char* data_ptr = buffer.data();
Local<ArrayBufferView> view = args[0].As<ArrayBufferView>();
if (buffer_length == 0) return args.GetReturnValue().SetEmptyString();
size_t start = 0;
size_t end = 0;
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[1], 0, &start));
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[2], buffer_length, &end));
if (end <= start) return args.GetReturnValue().SetEmptyString();
THROW_AND_RETURN_IF_OOB(Just(end <= buffer_length));
size_t length = end - start;
std::unique_ptr<char[]> data_copy;
if (view->Buffer()->IsSharedArrayBuffer()) {
data_copy = std::make_unique_for_overwrite<char[]>(length);
memcpy(data_copy.get(), data_ptr + start, length);
data_ptr = data_copy.get();
start = 0;
}
Local<Value> ret;
if (StringBytes::Encode(isolate, data_ptr + start, length, encoding)
.ToLocal(&ret)) {
args.GetReturnValue().Set(ret);
}
}
// Returns the number of bytes actually copied. This is normally |to_copy|, but
// V8 copies nothing (and returns 0) when the target is backed by a detached or
// immutable ArrayBuffer.
size_t CopyImpl(Local<Value> source_obj,
Local<Value> target_obj,
const size_t target_start,
const size_t source_start,
const size_t to_copy) {
Local<ArrayBufferView> source = source_obj.As<ArrayBufferView>();
Local<ArrayBufferView> target = target_obj.As<ArrayBufferView>();
Local<ArrayBuffer> source_ab = source->Buffer();
Local<ArrayBuffer> target_ab = target->Buffer();
const size_t source_offset = source->ByteOffset() + source_start;
const size_t target_offset = target->ByteOffset() + target_start;
// Defer byte-range clamping and detached/immutable handling to V8. When both
// sides are backed by a SharedArrayBuffer the relaxed atomic overload is
// used, which honors the SharedArrayBuffer memory model. Any other
// combination (both regular, or one of each) goes through the ArrayBuffer
// overload: it operates on the underlying backing store regardless of
// shared-ness, so a plain memmove is performed (matching the historical
// behavior for SharedArrayBuffer-backed buffers). The V8 API has no overload
// that mixes ArrayBuffer and SharedArrayBuffer, so the two must never be
// cross-cast.
if (source_ab->IsSharedArrayBuffer() && target_ab->IsSharedArrayBuffer()) {
return source_ab.As<SharedArrayBuffer>()->CopyArrayBufferBytes(
source_offset,
to_copy,
target_ab.As<SharedArrayBuffer>(),
target_offset);
}
return source_ab->CopyArrayBufferBytes(
source_offset, to_copy, target_ab, target_offset);
}
// Assume caller has properly validated args.
void SlowCopy(const FunctionCallbackInfo<Value>& args) {
Local<Value> source_obj = args[0];
Local<Value> target_obj = args[1];
// Byte offsets and lengths can exceed uint32 for buffers larger than 4 GiB,
// so they are passed and returned as doubles (exact for integers < 2^53).
const size_t target_start =
static_cast<size_t>(args[2].As<Number>()->Value());
const size_t source_start =
static_cast<size_t>(args[3].As<Number>()->Value());
const size_t to_copy = static_cast<size_t>(args[4].As<Number>()->Value());
const size_t copied =
CopyImpl(source_obj, target_obj, target_start, source_start, to_copy);
args.GetReturnValue().Set(static_cast<double>(copied));
}
// Assume caller has properly validated args.
double FastCopy(Local<Value> receiver,
Local<Value> source_obj,
Local<Value> target_obj,
double target_start,
double source_start,
double to_copy,
// NOLINTNEXTLINE(runtime/references)
FastApiCallbackOptions& options) {
TRACK_V8_FAST_API_CALL("buffer.copy");
HandleScope scope(options.isolate);
return static_cast<double>(CopyImpl(source_obj,
target_obj,
static_cast<size_t>(target_start),
static_cast<size_t>(source_start),
static_cast<size_t>(to_copy)));
}
static CFunction fast_copy(CFunction::Make(FastCopy));
void Fill(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
Local<Context> ctx = env->context();
THROW_AND_RETURN_UNLESS_BUFFER(env, args[0]);
SPREAD_BUFFER_ARG(args[0], ts_obj);
size_t start = 0;
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[2], 0, &start));
size_t end;
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[3], 0, &end));
size_t fill_length = end - start;
Local<String> str_obj;
size_t str_length;
enum encoding enc;
// OOB Check. Throw the error in JS.
if (start > end || fill_length + start > ts_obj_length)
return args.GetReturnValue().Set(-2);
// First check if Buffer has been passed.
if (Buffer::HasInstance(args[1])) {
SPREAD_BUFFER_ARG(args[1], fill_obj);
str_length = fill_obj_length;
memcpy(
ts_obj_data + start, fill_obj_data, std::min(str_length, fill_length));
goto start_fill;
}
// Then coerce everything that's not a string.
if (!args[1]->IsString()) {
uint32_t val;
if (!args[1]->Uint32Value(ctx).To(&val)) return;
int value = val & 255;
memset(ts_obj_data + start, value, fill_length);
return;
}
if (!args[1]->ToString(env->context()).ToLocal(&str_obj)) {
return;
}
enc = ParseEncoding(env->isolate(), args[4], UTF8);
// Can't use StringBytes::Write() in all cases. For example if attempting
// to write a two byte character into a one byte Buffer.
if (enc == UTF8) {
str_length = str_obj->Utf8LengthV2(env->isolate());
node::Utf8Value str(env->isolate(), args[1]);
memcpy(ts_obj_data + start, *str, std::min(str_length, fill_length));
} else if (enc == UCS2) {
str_length = str_obj->Length() * sizeof(uint16_t);
node::TwoByteValue str(env->isolate(), args[1]);
if constexpr (IsBigEndian())
CHECK(nbytes::SwapBytes16(reinterpret_cast<char*>(&str[0]), str_length));
memcpy(ts_obj_data + start, *str, std::min(str_length, fill_length));
} else {
// Write initial String to Buffer, then use that memory to copy remainder
// of string. Correct the string length for cases like HEX where less than
// the total string length is written.
str_length = StringBytes::Write(
env->isolate(), ts_obj_data + start, fill_length, str_obj, enc);
}
start_fill:
if (str_length >= fill_length)
return;
// If str_length is zero, then either an empty buffer was provided, or Write()
// indicated that no bytes could be written. If no bytes could be written,
// then return -1 because the fill value is invalid. This will trigger a throw
// in JavaScript. Silently failing should be avoided because it can lead to
// buffers with unexpected contents.
if (str_length == 0)
return args.GetReturnValue().Set(-1);
size_t in_there = str_length;
char* ptr = ts_obj_data + start + str_length;
while (in_there < fill_length - in_there) {
memcpy(ptr, ts_obj_data + start, in_there);
ptr += in_there;
in_there *= 2;
}
if (in_there < fill_length) {
memcpy(ptr, ts_obj_data + start, fill_length - in_there);
}
}
template <encoding encoding>
void StringWrite(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
THROW_AND_RETURN_UNLESS_BUFFER(env, args[0]);
SPREAD_BUFFER_ARG(args[0], ts_obj);
THROW_AND_RETURN_IF_NOT_STRING(env, args[1], "argument");
Local<String> str;
if (!args[1]->ToString(env->context()).ToLocal(&str)) {
return;
}
size_t offset = 0;
size_t max_length = 0;
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[2], 0, &offset));
if (offset > ts_obj_length) {
return node::THROW_ERR_BUFFER_OUT_OF_BOUNDS(
env, "\"offset\" is outside of buffer bounds");
}
THROW_AND_RETURN_IF_OOB(
ParseArrayIndex(env, args[3], ts_obj_length - offset, &max_length));
max_length = std::min(ts_obj_length - offset, max_length);
if (max_length == 0)
return args.GetReturnValue().Set(0);
uint32_t written = StringBytes::Write(
env->isolate(), ts_obj_data + offset, max_length, str, encoding);
args.GetReturnValue().Set(written);
}
void SlowByteLengthUtf8(const FunctionCallbackInfo<Value>& args) {
CHECK(args[0]->IsString());
Isolate* isolate = args.GetIsolate();
Local<String> str = args[0].As<String>();
// Below ~512 units, or for one-byte, V8's Utf8LengthV2 is faster.
if (str->Length() >= 512 && !str->IsOneByte()) {
String::ValueView view(isolate, str);
if (!view.is_one_byte()) {
// with_replacement matches Buffer.from's U+FFFD for lone surrogates.
size_t result =
simdutf::utf8_length_from_utf16_with_replacement(
reinterpret_cast<const char16_t*>(view.data16()), view.length())
.count;
args.GetReturnValue().Set(static_cast<uint64_t>(result));
return;
}
}
args.GetReturnValue().Set(static_cast<uint64_t>(str->Utf8LengthV2(isolate)));
}
uint32_t FastByteLengthUtf8(
Local<Value> receiver,
Local<Value> sourceValue,
FastApiCallbackOptions& options) { // NOLINT(runtime/references)
TRACK_V8_FAST_API_CALL("Buffer::FastByteLengthUtf8");
auto isolate = options.isolate;
HandleScope handleScope(isolate);
CHECK(sourceValue->IsString());
Local<String> sourceStr = sourceValue.As<String>();
if (!sourceStr->IsExternalOneByte()) {
// Below ~512 units, or for one-byte, V8's Utf8LengthV2 is faster.
if (sourceStr->Length() >= 512 && !sourceStr->IsOneByte()) {
String::ValueView view(isolate, sourceStr);
if (!view.is_one_byte()) {
// with_replacement matches Buffer.from's U+FFFD for lone surrogates.
return simdutf::utf8_length_from_utf16_with_replacement(
reinterpret_cast<const char16_t*>(view.data16()),
view.length())
.count;
}
}
return sourceStr->Utf8LengthV2(isolate);
}
auto source = sourceStr->GetExternalOneByteStringResource();
// For short inputs, the function call overhead to simdutf is maybe
// not worth it, reserve simdutf for long strings.
if (source->length() > 128) {
return simdutf::utf8_length_from_latin1(source->data(), source->length());
}
uint32_t length = source->length();
const auto input = reinterpret_cast<const uint8_t*>(source->data());
uint32_t answer = length;
uint32_t i = 0;
auto pop = [](uint64_t v) {
return static_cast<size_t>(((v >> 7) & UINT64_C(0x0101010101010101)) *
UINT64_C(0x0101010101010101) >>
56);
};
for (; i + 32 <= length; i += 32) {
uint64_t v;
memcpy(&v, input + i, 8);
answer += pop(v);
memcpy(&v, input + i + 8, 8);
answer += pop(v);
memcpy(&v, input + i + 16, 8);
answer += pop(v);
memcpy(&v, input + i + 24, 8);
answer += pop(v);
}
for (; i + 8 <= length; i += 8) {
uint64_t v;
memcpy(&v, input + i, 8);
answer += pop(v);
}
for (; i + 1 <= length; i += 1) {
answer += input[i] >> 7;
}
return answer;
}
static CFunction fast_byte_length_utf8(CFunction::Make(FastByteLengthUtf8));
// Normalize val to be an integer in the range of [1, -1] since
// implementations of memcmp() can vary by platform.
static int normalizeCompareVal(int val, size_t a_length, size_t b_length) {
if (val == 0) {
if (a_length > b_length)
return 1;
else if (a_length < b_length)
return -1;
} else {
if (val > 0)
return 1;
else
return -1;
}
return val;
}
void CompareOffset(const FunctionCallbackInfo<Value> &args) {
Environment* env = Environment::GetCurrent(args);
THROW_AND_RETURN_UNLESS_BUFFER(env, args[0]);
THROW_AND_RETURN_UNLESS_BUFFER(env, args[1]);
ArrayBufferViewContents<char> source(args[0]);
ArrayBufferViewContents<char> target(args[1]);
size_t target_start = 0;
size_t source_start = 0;
size_t source_end = 0;
size_t target_end = 0;
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[2], 0, &target_start));
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[3], 0, &source_start));
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[4], target.length(),
&target_end));
THROW_AND_RETURN_IF_OOB(ParseArrayIndex(env, args[5], source.length(),
&source_end));
if (source_start > source.length())
return THROW_ERR_OUT_OF_RANGE(
env, "The value of \"sourceStart\" is out of range.");
if (target_start > target.length())
return THROW_ERR_OUT_OF_RANGE(
env, "The value of \"targetStart\" is out of range.");
CHECK_LE(source_start, source_end);
CHECK_LE(target_start, target_end);
size_t to_cmp =
std::min(std::min(source_end - source_start, target_end - target_start),
source.length() - source_start);
int val = normalizeCompareVal(to_cmp > 0 ?
memcmp(source.data() + source_start,
target.data() + target_start,
to_cmp) : 0,
source_end - source_start,
target_end - target_start);
args.GetReturnValue().Set(val);
}
int32_t CompareImpl(Local<Value> a_obj, Local<Value> b_obj) {
ArrayBufferViewContents<char> a(a_obj);
ArrayBufferViewContents<char> b(b_obj);
size_t cmp_length = std::min(a.length(), b.length());
return normalizeCompareVal(
cmp_length > 0 ? memcmp(a.data(), b.data(), cmp_length) : 0,
a.length(),
b.length());
}
void Compare(const FunctionCallbackInfo<Value> &args) {
Environment* env = Environment::GetCurrent(args);
THROW_AND_RETURN_UNLESS_BUFFER(env, args[0]);
THROW_AND_RETURN_UNLESS_BUFFER(env, args[1]);
int val = CompareImpl(args[0], args[1]);
args.GetReturnValue().Set(val);
}
int32_t FastCompare(Local<Value>,
Local<Value> a_obj,
Local<Value> b_obj,
// NOLINTNEXTLINE(runtime/references)
FastApiCallbackOptions& options) {
HandleScope scope(options.isolate);
return CompareImpl(a_obj, b_obj);
}
static CFunction fast_compare(CFunction::Make(FastCompare));
// Computes the offset for starting an indexOf or lastIndexOf search.
// Returns either a valid offset in [0...<length - 1>], ie inside the Buffer,
// or -1 to signal that there is no possible match.
int64_t IndexOfOffset(size_t length,
int64_t offset_i64,
int64_t needle_length,
bool is_forward) {
int64_t length_i64 = static_cast<int64_t>(length);
if (offset_i64 < 0) {
if (offset_i64 + length_i64 >= 0) {
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