lts/src/node_i18n.cc
// 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.
/*
* notes: by srl295
* - When in NODE_HAVE_SMALL_ICU mode, ICU is linked against "stub" (null) data
* ( stubdata/libicudata.a ) containing nothing, no data, and it's also
* linked against a "small" data file which the SMALL_ICUDATA_ENTRY_POINT
* macro names. That's the "english+root" data.
*
* If icu_data_path is non-null, the user has provided a path and we assume
* it goes somewhere useful. We set that path in ICU, and exit.
* If icu_data_path is null, they haven't set a path and we want the
* "english+root" data. We call
* udata_setCommonData(SMALL_ICUDATA_ENTRY_POINT,...)
* to load up the english+root data.
*
* - when NOT in NODE_HAVE_SMALL_ICU mode, ICU is linked directly with its full
* data. All of the variables and command line options for changing data at
* runtime are disabled, as they wouldn't fully override the internal data.
* See: http://bugs.icu-project.org/trac/ticket/10924
*/
#include "node_i18n.h"
#if defined(NODE_HAVE_I18N_SUPPORT)
#include "base_object-inl.h"
#include "node.h"
#include "node_buffer.h"
#include "node_errors.h"
#include "node_internals.h"
#include "util-inl.h"
#include "v8.h"
#include <unicode/utypes.h>
#include <unicode/putil.h>
#include <unicode/uchar.h>
#include <unicode/uclean.h>
#include <unicode/udata.h>
#include <unicode/uidna.h>
#include <unicode/ucnv.h>
#include <unicode/utf8.h>
#include <unicode/utf16.h>
#include <unicode/timezone.h>
#include <unicode/ulocdata.h>
#include <unicode/uvernum.h>
#include <unicode/uversion.h>
#include <unicode/ustring.h>
#ifdef NODE_HAVE_SMALL_ICU
/* if this is defined, we have a 'secondary' entry point.
compare following to utypes.h defs for U_ICUDATA_ENTRY_POINT */
#define SMALL_ICUDATA_ENTRY_POINT \
SMALL_DEF2(U_ICU_VERSION_MAJOR_NUM, U_LIB_SUFFIX_C_NAME)
#define SMALL_DEF2(major, suff) SMALL_DEF(major, suff)
#ifndef U_LIB_SUFFIX_C_NAME
#define SMALL_DEF(major, suff) icusmdt##major##_dat
#else
#define SMALL_DEF(major, suff) icusmdt##suff##major##_dat
#endif
extern "C" const char U_DATA_API SMALL_ICUDATA_ENTRY_POINT[];
#endif
namespace node {
using v8::Context;
using v8::FunctionCallbackInfo;
using v8::FunctionTemplate;
using v8::Int32;
using v8::Isolate;
using v8::Local;
using v8::MaybeLocal;
using v8::NewStringType;
using v8::Object;
using v8::ObjectTemplate;
using v8::String;
using v8::Uint8Array;
using v8::Value;
namespace i18n {
namespace {
template <typename T>
MaybeLocal<Object> ToBufferEndian(Environment* env, MaybeStackBuffer<T>* buf) {
MaybeLocal<Object> ret = Buffer::New(env, buf);
if (ret.IsEmpty())
return ret;
static_assert(sizeof(T) == 1 || sizeof(T) == 2,
"Currently only one- or two-byte buffers are supported");
if (sizeof(T) > 1 && IsBigEndian()) {
SPREAD_BUFFER_ARG(ret.ToLocalChecked(), retbuf);
SwapBytes16(retbuf_data, retbuf_length);
}
return ret;
}
// One-Shot Converters
void CopySourceBuffer(MaybeStackBuffer<UChar>* dest,
const char* data,
const size_t length,
const size_t length_in_chars) {
dest->AllocateSufficientStorage(length_in_chars);
char* dst = reinterpret_cast<char*>(**dest);
memcpy(dst, data, length);
if (IsBigEndian()) {
SwapBytes16(dst, length);
}
}
typedef MaybeLocal<Object> (*TranscodeFunc)(Environment* env,
const char* fromEncoding,
const char* toEncoding,
const char* source,
const size_t source_length,
UErrorCode* status);
MaybeLocal<Object> Transcode(Environment* env,
const char* fromEncoding,
const char* toEncoding,
const char* source,
const size_t source_length,
UErrorCode* status) {
*status = U_ZERO_ERROR;
MaybeLocal<Object> ret;
MaybeStackBuffer<char> result;
Converter to(toEncoding, "?");
Converter from(fromEncoding);
const uint32_t limit = source_length * to.max_char_size();
result.AllocateSufficientStorage(limit);
char* target = *result;
ucnv_convertEx(to.conv(), from.conv(), &target, target + limit,
&source, source + source_length, nullptr, nullptr,
nullptr, nullptr, true, true, status);
if (U_SUCCESS(*status)) {
result.SetLength(target - &result[0]);
ret = ToBufferEndian(env, &result);
}
return ret;
}
MaybeLocal<Object> TranscodeToUcs2(Environment* env,
const char* fromEncoding,
const char* toEncoding,
const char* source,
const size_t source_length,
UErrorCode* status) {
*status = U_ZERO_ERROR;
MaybeLocal<Object> ret;
MaybeStackBuffer<UChar> destbuf(source_length);
Converter from(fromEncoding);
const size_t length_in_chars = source_length * sizeof(UChar);
ucnv_toUChars(from.conv(), *destbuf, length_in_chars,
source, source_length, status);
if (U_SUCCESS(*status))
ret = ToBufferEndian(env, &destbuf);
return ret;
}
MaybeLocal<Object> TranscodeFromUcs2(Environment* env,
const char* fromEncoding,
const char* toEncoding,
const char* source,
const size_t source_length,
UErrorCode* status) {
*status = U_ZERO_ERROR;
MaybeStackBuffer<UChar> sourcebuf;
MaybeLocal<Object> ret;
Converter to(toEncoding, "?");
const size_t length_in_chars = source_length / sizeof(UChar);
CopySourceBuffer(&sourcebuf, source, source_length, length_in_chars);
MaybeStackBuffer<char> destbuf(length_in_chars);
const uint32_t len = ucnv_fromUChars(to.conv(), *destbuf, length_in_chars,
*sourcebuf, length_in_chars, status);
if (U_SUCCESS(*status)) {
destbuf.SetLength(len);
ret = ToBufferEndian(env, &destbuf);
}
return ret;
}
MaybeLocal<Object> TranscodeUcs2FromUtf8(Environment* env,
const char* fromEncoding,
const char* toEncoding,
const char* source,
const size_t source_length,
UErrorCode* status) {
*status = U_ZERO_ERROR;
MaybeStackBuffer<UChar> destbuf;
int32_t result_length;
u_strFromUTF8(*destbuf, destbuf.capacity(), &result_length,
source, source_length, status);
MaybeLocal<Object> ret;
if (U_SUCCESS(*status)) {
destbuf.SetLength(result_length);
ret = ToBufferEndian(env, &destbuf);
} else if (*status == U_BUFFER_OVERFLOW_ERROR) {
*status = U_ZERO_ERROR;
destbuf.AllocateSufficientStorage(result_length);
u_strFromUTF8(*destbuf, result_length, &result_length,
source, source_length, status);
if (U_SUCCESS(*status)) {
destbuf.SetLength(result_length);
ret = ToBufferEndian(env, &destbuf);
}
}
return ret;
}
MaybeLocal<Object> TranscodeUtf8FromUcs2(Environment* env,
const char* fromEncoding,
const char* toEncoding,
const char* source,
const size_t source_length,
UErrorCode* status) {
*status = U_ZERO_ERROR;
MaybeLocal<Object> ret;
const size_t length_in_chars = source_length / sizeof(UChar);
int32_t result_length;
MaybeStackBuffer<UChar> sourcebuf;
MaybeStackBuffer<char> destbuf;
CopySourceBuffer(&sourcebuf, source, source_length, length_in_chars);
u_strToUTF8(*destbuf, destbuf.capacity(), &result_length,
*sourcebuf, length_in_chars, status);
if (U_SUCCESS(*status)) {
destbuf.SetLength(result_length);
ret = ToBufferEndian(env, &destbuf);
} else if (*status == U_BUFFER_OVERFLOW_ERROR) {
*status = U_ZERO_ERROR;
destbuf.AllocateSufficientStorage(result_length);
u_strToUTF8(*destbuf, result_length, &result_length, *sourcebuf,
length_in_chars, status);
if (U_SUCCESS(*status)) {
destbuf.SetLength(result_length);
ret = ToBufferEndian(env, &destbuf);
}
}
return ret;
}
const char* EncodingName(const enum encoding encoding) {
switch (encoding) {
case ASCII: return "us-ascii";
case LATIN1: return "iso8859-1";
case UCS2: return "utf16le";
case UTF8: return "utf-8";
default: return nullptr;
}
}
bool SupportedEncoding(const enum encoding encoding) {
switch (encoding) {
case ASCII:
case LATIN1:
case UCS2:
case UTF8: return true;
default: return false;
}
}
void Transcode(const FunctionCallbackInfo<Value>&args) {
Environment* env = Environment::GetCurrent(args);
Isolate* isolate = env->isolate();
UErrorCode status = U_ZERO_ERROR;
MaybeLocal<Object> result;
ArrayBufferViewContents<char> input(args[0]);
const enum encoding fromEncoding = ParseEncoding(isolate, args[1], BUFFER);
const enum encoding toEncoding = ParseEncoding(isolate, args[2], BUFFER);
if (SupportedEncoding(fromEncoding) && SupportedEncoding(toEncoding)) {
TranscodeFunc tfn = &Transcode;
switch (fromEncoding) {
case ASCII:
case LATIN1:
if (toEncoding == UCS2)
tfn = &TranscodeToUcs2;
break;
case UTF8:
if (toEncoding == UCS2)
tfn = &TranscodeUcs2FromUtf8;
break;
case UCS2:
switch (toEncoding) {
case UCS2:
tfn = &Transcode;
break;
case UTF8:
tfn = &TranscodeUtf8FromUcs2;
break;
default:
tfn = &TranscodeFromUcs2;
}
break;
default:
// This should not happen because of the SupportedEncoding checks
ABORT();
}
result = tfn(env, EncodingName(fromEncoding), EncodingName(toEncoding),
input.data(), input.length(), &status);
} else {
status = U_ILLEGAL_ARGUMENT_ERROR;
}
if (result.IsEmpty())
return args.GetReturnValue().Set(status);
return args.GetReturnValue().Set(result.ToLocalChecked());
}
void ICUErrorName(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(args[0]->IsInt32());
UErrorCode status = static_cast<UErrorCode>(args[0].As<Int32>()->Value());
args.GetReturnValue().Set(
String::NewFromUtf8(env->isolate(),
u_errorName(status),
NewStringType::kNormal).ToLocalChecked());
}
} // anonymous namespace
Converter::Converter(const char* name, const char* sub) {
UErrorCode status = U_ZERO_ERROR;
UConverter* conv = ucnv_open(name, &status);
CHECK(U_SUCCESS(status));
conv_.reset(conv);
set_subst_chars(sub);
}
Converter::Converter(UConverter* converter, const char* sub)
: conv_(converter) {
set_subst_chars(sub);
}
void Converter::set_subst_chars(const char* sub) {
CHECK(conv_);
UErrorCode status = U_ZERO_ERROR;
if (sub != nullptr) {
ucnv_setSubstChars(conv_.get(), sub, strlen(sub), &status);
CHECK(U_SUCCESS(status));
}
}
void Converter::reset() {
ucnv_reset(conv_.get());
}
size_t Converter::min_char_size() const {
CHECK(conv_);
return ucnv_getMinCharSize(conv_.get());
}
size_t Converter::max_char_size() const {
CHECK(conv_);
return ucnv_getMaxCharSize(conv_.get());
}
void ConverterObject::Has(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK_GE(args.Length(), 1);
Utf8Value label(env->isolate(), args[0]);
UErrorCode status = U_ZERO_ERROR;
ConverterPointer conv(ucnv_open(*label, &status));
args.GetReturnValue().Set(!!U_SUCCESS(status));
}
void ConverterObject::Create(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
Local<ObjectTemplate> t = env->i18n_converter_template();
Local<Object> obj;
if (!t->NewInstance(env->context()).ToLocal(&obj)) return;
CHECK_GE(args.Length(), 2);
Utf8Value label(env->isolate(), args[0]);
int flags = args[1]->Uint32Value(env->context()).ToChecked();
bool fatal =
(flags & CONVERTER_FLAGS_FATAL) == CONVERTER_FLAGS_FATAL;
UErrorCode status = U_ZERO_ERROR;
UConverter* conv = ucnv_open(*label, &status);
if (U_FAILURE(status))
return;
if (fatal) {
status = U_ZERO_ERROR;
ucnv_setToUCallBack(conv, UCNV_TO_U_CALLBACK_STOP,
nullptr, nullptr, nullptr, &status);
}
new ConverterObject(env, obj, conv, flags);
args.GetReturnValue().Set(obj);
}
void ConverterObject::Decode(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK_GE(args.Length(), 3); // Converter, Buffer, Flags
ConverterObject* converter;
ASSIGN_OR_RETURN_UNWRAP(&converter, args[0].As<Object>());
ArrayBufferViewContents<char> input(args[1]);
int flags = args[2]->Uint32Value(env->context()).ToChecked();
UErrorCode status = U_ZERO_ERROR;
MaybeStackBuffer<UChar> result;
MaybeLocal<Object> ret;
size_t limit = converter->min_char_size() * input.length();
if (limit > 0)
result.AllocateSufficientStorage(limit);
UBool flush = (flags & CONVERTER_FLAGS_FLUSH) == CONVERTER_FLAGS_FLUSH;
auto cleanup = OnScopeLeave([&]() {
if (flush) {
// Reset the converter state.
converter->set_bom_seen(false);
converter->reset();
}
});
const char* source = input.data();
size_t source_length = input.length();
UChar* target = *result;
ucnv_toUnicode(converter->conv(),
&target,
target + (limit * sizeof(UChar)),
&source,
source + source_length,
nullptr,
flush,
&status);
if (U_SUCCESS(status)) {
bool omit_initial_bom = false;
if (limit > 0) {
result.SetLength(target - &result[0]);
if (result.length() > 0 &&
converter->unicode() &&
!converter->ignore_bom() &&
!converter->bom_seen()) {
// If the very first result in the stream is a BOM, and we are not
// explicitly told to ignore it, then we mark it for discarding.
if (result[0] == 0xFEFF)
omit_initial_bom = true;
converter->set_bom_seen(true);
}
}
ret = ToBufferEndian(env, &result);
if (omit_initial_bom && !ret.IsEmpty()) {
// Peform `ret = ret.slice(2)`.
CHECK(ret.ToLocalChecked()->IsUint8Array());
Local<Uint8Array> orig_ret = ret.ToLocalChecked().As<Uint8Array>();
ret = Buffer::New(env,
orig_ret->Buffer(),
orig_ret->ByteOffset() + 2,
orig_ret->ByteLength() - 2)
.FromMaybe(Local<Uint8Array>());
}
if (!ret.IsEmpty())
args.GetReturnValue().Set(ret.ToLocalChecked());
return;
}
args.GetReturnValue().Set(status);
}
ConverterObject::ConverterObject(
Environment* env,
Local<Object> wrap,
UConverter* converter,
int flags,
const char* sub)
: BaseObject(env, wrap),
Converter(converter, sub),
flags_(flags) {
MakeWeak();
switch (ucnv_getType(converter)) {
case UCNV_UTF8:
case UCNV_UTF16_BigEndian:
case UCNV_UTF16_LittleEndian:
flags_ |= CONVERTER_FLAGS_UNICODE;
break;
default: {
// Fall through
}
}
}
bool InitializeICUDirectory(const std::string& path) {
UErrorCode status = U_ZERO_ERROR;
if (path.empty()) {
#ifdef NODE_HAVE_SMALL_ICU
// install the 'small' data.
udata_setCommonData(&SMALL_ICUDATA_ENTRY_POINT, &status);
#else // !NODE_HAVE_SMALL_ICU
// no small data, so nothing to do.
#endif // !NODE_HAVE_SMALL_ICU
} else {
u_setDataDirectory(path.c_str());
u_init(&status);
}
return status == U_ZERO_ERROR;
}
int32_t ToUnicode(MaybeStackBuffer<char>* buf,
const char* input,
size_t length) {
UErrorCode status = U_ZERO_ERROR;
uint32_t options = UIDNA_NONTRANSITIONAL_TO_UNICODE;
UIDNA* uidna = uidna_openUTS46(options, &status);
if (U_FAILURE(status))
return -1;
UIDNAInfo info = UIDNA_INFO_INITIALIZER;
int32_t len = uidna_nameToUnicodeUTF8(uidna,
input, length,
**buf, buf->capacity(),
&info,
&status);
// Do not check info.errors like we do with ToASCII since ToUnicode always
// returns a string, despite any possible errors that may have occurred.
if (status == U_BUFFER_OVERFLOW_ERROR) {
status = U_ZERO_ERROR;
buf->AllocateSufficientStorage(len);
len = uidna_nameToUnicodeUTF8(uidna,
input, length,
**buf, buf->capacity(),
&info,
&status);
}
// info.errors is ignored as UTS #46 ToUnicode always produces a Unicode
// string, regardless of whether an error occurred.
if (U_FAILURE(status)) {
len = -1;
buf->SetLength(0);
} else {
buf->SetLength(len);
}
uidna_close(uidna);
return len;
}
int32_t ToASCII(MaybeStackBuffer<char>* buf,
const char* input,
size_t length,
enum idna_mode mode) {
UErrorCode status = U_ZERO_ERROR;
uint32_t options = // CheckHyphens = false; handled later
UIDNA_CHECK_BIDI | // CheckBidi = true
UIDNA_CHECK_CONTEXTJ | // CheckJoiners = true
UIDNA_NONTRANSITIONAL_TO_ASCII; // Nontransitional_Processing
if (mode == IDNA_STRICT) {
options |= UIDNA_USE_STD3_RULES; // UseSTD3ASCIIRules = beStrict
// VerifyDnsLength = beStrict;
// handled later
}
UIDNA* uidna = uidna_openUTS46(options, &status);
if (U_FAILURE(status))
return -1;
UIDNAInfo info = UIDNA_INFO_INITIALIZER;
int32_t len = uidna_nameToASCII_UTF8(uidna,
input, length,
**buf, buf->capacity(),
&info,
&status);
if (status == U_BUFFER_OVERFLOW_ERROR) {
status = U_ZERO_ERROR;
buf->AllocateSufficientStorage(len);
len = uidna_nameToASCII_UTF8(uidna,
input, length,
**buf, buf->capacity(),
&info,
&status);
}
// In UTS #46 which specifies ToASCII, certain error conditions are
// configurable through options, and the WHATWG URL Standard promptly elects
// to disable some of them to accommodate for real-world use cases.
// Unfortunately, ICU4C's IDNA module does not support disabling some of
// these options through `options` above, and thus continues throwing
// unnecessary errors. To counter this situation, we just filter out the
// errors that may have happened afterwards, before deciding whether to
// return an error from this function.
// CheckHyphens = false
// (Specified in the current UTS #46 draft rev. 18.)
// Refs:
// - https://github.com/whatwg/url/issues/53
// - https://github.com/whatwg/url/pull/309
// - http://www.unicode.org/review/pri317/
// - http://www.unicode.org/reports/tr46/tr46-18.html
// - https://www.icann.org/news/announcement-2000-01-07-en
info.errors &= ~UIDNA_ERROR_HYPHEN_3_4;
info.errors &= ~UIDNA_ERROR_LEADING_HYPHEN;
info.errors &= ~UIDNA_ERROR_TRAILING_HYPHEN;
if (mode != IDNA_STRICT) {
// VerifyDnsLength = beStrict
info.errors &= ~UIDNA_ERROR_EMPTY_LABEL;
info.errors &= ~UIDNA_ERROR_LABEL_TOO_LONG;
info.errors &= ~UIDNA_ERROR_DOMAIN_NAME_TOO_LONG;
}
if (U_FAILURE(status) || (mode != IDNA_LENIENT && info.errors != 0)) {
len = -1;
buf->SetLength(0);
} else {
buf->SetLength(len);
}
uidna_close(uidna);
return len;
}
static void ToUnicode(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK_GE(args.Length(), 1);
CHECK(args[0]->IsString());
Utf8Value val(env->isolate(), args[0]);
MaybeStackBuffer<char> buf;
int32_t len = ToUnicode(&buf, *val, val.length());
if (len < 0) {
return THROW_ERR_INVALID_ARG_VALUE(env, "Cannot convert name to Unicode");
}
args.GetReturnValue().Set(
String::NewFromUtf8(env->isolate(),
*buf,
NewStringType::kNormal,
len).ToLocalChecked());
}
static void ToASCII(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK_GE(args.Length(), 1);
CHECK(args[0]->IsString());
Utf8Value val(env->isolate(), args[0]);
// optional arg
bool lenient = args[1]->BooleanValue(env->isolate());
enum idna_mode mode = lenient ? IDNA_LENIENT : IDNA_DEFAULT;
MaybeStackBuffer<char> buf;
int32_t len = ToASCII(&buf, *val, val.length(), mode);
if (len < 0) {
return THROW_ERR_INVALID_ARG_VALUE(env, "Cannot convert name to ASCII");
}
args.GetReturnValue().Set(
String::NewFromUtf8(env->isolate(),
*buf,
NewStringType::kNormal,
len).ToLocalChecked());
}
// This is similar to wcwidth except that it takes the current unicode
// character properties database into consideration, allowing it to
// correctly calculate the column widths of things like emoji's and
// newer wide characters. wcwidth, on the other hand, uses a fixed
// algorithm that does not take things like emoji into proper
// consideration.
//
// TODO(TimothyGu): Investigate Cc (C0/C1 control codes). Both VTE (used by
// GNOME Terminal) and Konsole don't consider them to be zero-width (see refs
// below), and when printed in VTE it is Narrow. However GNOME Terminal doesn't
// allow it to be input. Linux's PTY terminal prints control characters as
// Narrow rhombi.
//
// TODO(TimothyGu): Investigate Hangul jamo characters. Medial vowels and final
// consonants are 0-width when combined with initial consonants; otherwise they
// are technically Wide. But many terminals (including Konsole and
// VTE/GLib-based) implement all medials and finals as 0-width.
//
// Refs: https://eev.ee/blog/2015/09/12/dark-corners-of-unicode/#combining-characters-and-character-width
// Refs: https://github.com/GNOME/glib/blob/79e4d4c6be/glib/guniprop.c#L388-L420
// Refs: https://github.com/KDE/konsole/blob/8c6a5d13c0/src/konsole_wcwidth.cpp#L101-L223
static int GetColumnWidth(UChar32 codepoint,
bool ambiguous_as_full_width = false) {
// UCHAR_EAST_ASIAN_WIDTH is the Unicode property that identifies a
// codepoint as being full width, wide, ambiguous, neutral, narrow,
// or halfwidth.
const int eaw = u_getIntPropertyValue(codepoint, UCHAR_EAST_ASIAN_WIDTH);
switch (eaw) {
case U_EA_FULLWIDTH:
case U_EA_WIDE:
return 2;
case U_EA_AMBIGUOUS:
// See: http://www.unicode.org/reports/tr11/#Ambiguous for details
if (ambiguous_as_full_width) {
return 2;
}
// If ambiguous_as_full_width is false:
// Fall through
case U_EA_NEUTRAL:
if (u_hasBinaryProperty(codepoint, UCHAR_EMOJI_PRESENTATION)) {
return 2;
}
// Fall through
case U_EA_HALFWIDTH:
case U_EA_NARROW:
default:
const auto zero_width_mask = U_GC_CC_MASK | // C0/C1 control code
U_GC_CF_MASK | // Format control character
U_GC_ME_MASK | // Enclosing mark
U_GC_MN_MASK; // Nonspacing mark
if (codepoint != 0x00AD && // SOFT HYPHEN is Cf but not zero-width
((U_MASK(u_charType(codepoint)) & zero_width_mask) ||
u_hasBinaryProperty(codepoint, UCHAR_EMOJI_MODIFIER))) {
return 0;
}
return 1;
}
}
// Returns the column width for the given String.
static void GetStringWidth(const FunctionCallbackInfo<Value>& args) {
Environment* env = Environment::GetCurrent(args);
CHECK(args[0]->IsString());
bool ambiguous_as_full_width = args[1]->IsTrue();
bool expand_emoji_sequence = !args[2]->IsBoolean() || args[2]->IsTrue();
TwoByteValue value(env->isolate(), args[0]);
// reinterpret_cast is required by windows to compile
UChar* str = reinterpret_cast<UChar*>(*value);
static_assert(sizeof(*str) == sizeof(**value),
"sizeof(*str) == sizeof(**value)");
UChar32 c = 0;
UChar32 p;
size_t n = 0;
uint32_t width = 0;
while (n < value.length()) {
p = c;
U16_NEXT(str, n, value.length(), c);
// Don't count individual emoji codepoints that occur within an
// emoji sequence. This is not necessarily foolproof. Some
// environments display emoji sequences in the appropriate
// condensed form (as a single emoji glyph), other environments
// may not understand an emoji sequence and will display each
// individual emoji separately. When this happens, the width
// calculated will be off, and there's no reliable way of knowing
// in advance if a particular sequence is going to be supported.
// The expand_emoji_sequence option allows the caller to skip this
// check and count each code within an emoji sequence separately.
// https://www.unicode.org/reports/tr51/tr51-16.html#Emoji_ZWJ_Sequences
if (!expand_emoji_sequence &&
n > 0 && p == 0x200d && // 0x200d == ZWJ (zero width joiner)
(u_hasBinaryProperty(c, UCHAR_EMOJI_PRESENTATION) ||
u_hasBinaryProperty(c, UCHAR_EMOJI_MODIFIER))) {
continue;
}
width += GetColumnWidth(c, ambiguous_as_full_width);
}
args.GetReturnValue().Set(width);
}
void Initialize(Local<Object> target,
Local<Value> unused,
Local<Context> context,
void* priv) {
Environment* env = Environment::GetCurrent(context);
env->SetMethod(target, "toUnicode", ToUnicode);
env->SetMethod(target, "toASCII", ToASCII);
env->SetMethod(target, "getStringWidth", GetStringWidth);
// One-shot converters
env->SetMethod(target, "icuErrName", ICUErrorName);
env->SetMethod(target, "transcode", Transcode);
// ConverterObject
{
Local<FunctionTemplate> t = FunctionTemplate::New(env->isolate());
t->InstanceTemplate()->SetInternalFieldCount(
ConverterObject::kInternalFieldCount);
Local<String> converter_string =
FIXED_ONE_BYTE_STRING(env->isolate(), "Converter");
t->SetClassName(converter_string);
env->set_i18n_converter_template(t->InstanceTemplate());
}
env->SetMethod(target, "getConverter", ConverterObject::Create);
env->SetMethod(target, "decode", ConverterObject::Decode);
env->SetMethod(target, "hasConverter", ConverterObject::Has);
}
} // namespace i18n
} // namespace node
NODE_MODULE_CONTEXT_AWARE_INTERNAL(icu, node::i18n::Initialize)
#endif // NODE_HAVE_I18N_SUPPORT