base/i18n/icu_string_conversions.cc - chromium/src - Git at Google

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "base/i18n/icu_string_conversions.h"

 #include <stddef.h>
 #include <stdint.h>

 #include <memory>
 #include <vector>

 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "third_party/icu/source/common/unicode/normalizer2.h"
 #include "third_party/icu/source/common/unicode/ucnv.h"
 #include "third_party/icu/source/common/unicode/ucnv_cb.h"
 #include "third_party/icu/source/common/unicode/ucnv_err.h"
 #include "third_party/icu/source/common/unicode/ustring.h"

 namespace base {

 namespace {
 // ToUnicodeCallbackSubstitute() is based on UCNV_TO_U_CALLBACK_SUBSTITUTE
 // in source/common/ucnv_err.c.

 // Copyright (c) 1995-2006 International Business Machines Corporation
 // and others
 //
 // All rights reserved.
 //

 // 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, and/or
 // sell copies of the Software, and to permit persons to whom the Software
 // is furnished to do so, provided that the above copyright notice(s) and
 // this permission notice appear in all copies of the Software and that
 // both the above copyright notice(s) and this permission notice appear in
 // supporting documentation.
 //
 // 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
 // OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
 // INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
 // OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
 // OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 // OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE
 // OR PERFORMANCE OF THIS SOFTWARE.
 //
 // Except as contained in this notice, the name of a copyright holder
 // shall not be used in advertising or otherwise to promote the sale, use
 // or other dealings in this Software without prior written authorization
 // of the copyright holder.

 //  ___________________________________________________________________________
 //
 // All trademarks and registered trademarks mentioned herein are the property
 // of their respective owners.

 void ToUnicodeCallbackSubstitute(const void* context,
                                  UConverterToUnicodeArgs *to_args,
                                  const char* code_units,
                                  int32_t length,
                                  UConverterCallbackReason reason,
                                  UErrorCode * err) {
   static const UChar kReplacementChar = 0xFFFD;
   if (reason <= UCNV_IRREGULAR) {
     if (context == nullptr ||
         (*(reinterpret_cast<const char*>(context)) == 'i' &&
          reason == UCNV_UNASSIGNED)) {
       *err = U_ZERO_ERROR;
       ucnv_cbToUWriteUChars(to_args, &kReplacementChar, 1, 0, err);
       }
       // else the caller must have set the error code accordingly.
   }
   // else ignore the reset, close and clone calls.
 }

 bool ConvertFromUTF16(UConverter* converter, const UChar* uchar_src,
                       int uchar_len, OnStringConversionError::Type on_error,
                       std::string* encoded) {
   int encoded_max_length = UCNV_GET_MAX_BYTES_FOR_STRING(uchar_len,
       ucnv_getMaxCharSize(converter));
   encoded->resize(encoded_max_length);

   UErrorCode status = U_ZERO_ERROR;

   // Setup our error handler.
   switch (on_error) {
     case OnStringConversionError::FAIL:
       ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_STOP, nullptr,
                             nullptr, nullptr, &status);
       break;
     case OnStringConversionError::SKIP:
     case OnStringConversionError::SUBSTITUTE:
       ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_SKIP, nullptr,
                             nullptr, nullptr, &status);
       break;
     default:
       NOTREACHED();
   }

   // ucnv_fromUChars returns size not including terminating null
   int actual_size = ucnv_fromUChars(converter, &(*encoded)[0],
       encoded_max_length, uchar_src, uchar_len, &status);
   encoded->resize(actual_size);
   ucnv_close(converter);
   if (U_SUCCESS(status))
     return true;
   encoded->clear();  // Make sure the output is empty on error.
   return false;
 }

 // Set up our error handler for ToUTF-16 converters
 void SetUpErrorHandlerForToUChars(OnStringConversionError::Type on_error,
                                   UConverter* converter, UErrorCode* status) {
   switch (on_error) {
     case OnStringConversionError::FAIL:
       ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_STOP, nullptr, nullptr,
                           nullptr, status);
       break;
     case OnStringConversionError::SKIP:
       ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_SKIP, nullptr, nullptr,
                           nullptr, status);
       break;
     case OnStringConversionError::SUBSTITUTE:
       ucnv_setToUCallBack(converter, ToUnicodeCallbackSubstitute, nullptr,
                           nullptr, nullptr, status);
       break;
     default:
       NOTREACHED();
   }
 }

 }  // namespace

 // Codepage <-> Wide/UTF-16  ---------------------------------------------------

 bool UTF16ToCodepage(const string16& utf16,
                      const char* codepage_name,
                      OnStringConversionError::Type on_error,
                      std::string* encoded) {
   encoded->clear();

   UErrorCode status = U_ZERO_ERROR;
   UConverter* converter = ucnv_open(codepage_name, &status);
   if (!U_SUCCESS(status))
     return false;

   return ConvertFromUTF16(converter, utf16.c_str(),
                           static_cast<int>(utf16.length()), on_error, encoded);
 }

 bool CodepageToUTF16(const std::string& encoded,
                      const char* codepage_name,
                      OnStringConversionError::Type on_error,
                      string16* utf16) {
   utf16->clear();

   UErrorCode status = U_ZERO_ERROR;
   UConverter* converter = ucnv_open(codepage_name, &status);
   if (!U_SUCCESS(status))
     return false;

   // Even in the worst case, the maximum length in 2-byte units of UTF-16
   // output would be at most the same as the number of bytes in input. There
   // is no single-byte encoding in which a character is mapped to a
   // non-BMP character requiring two 2-byte units.
   //
   // Moreover, non-BMP characters in legacy multibyte encodings
   // (e.g. EUC-JP, GB18030) take at least 2 bytes. The only exceptions are
   // BOCU and SCSU, but we don't care about them.
   size_t uchar_max_length = encoded.length() + 1;

   SetUpErrorHandlerForToUChars(on_error, converter, &status);
   std::unique_ptr<char16[]> buffer(new char16[uchar_max_length]);
   int actual_size = ucnv_toUChars(converter, buffer.get(),
       static_cast<int>(uchar_max_length), encoded.data(),
       static_cast<int>(encoded.length()), &status);
   ucnv_close(converter);
   if (!U_SUCCESS(status)) {
     utf16->clear();  // Make sure the output is empty on error.
     return false;
   }

   utf16->assign(buffer.get(), actual_size);
   return true;
 }

 bool ConvertToUtf8AndNormalize(const std::string& text,
                                const std::string& charset,
                                std::string* result) {
   result->clear();
   string16 utf16;
   if (!CodepageToUTF16(
       text, charset.c_str(), OnStringConversionError::FAIL, &utf16))
     return false;

   UErrorCode status = U_ZERO_ERROR;
   const icu::Normalizer2* normalizer = icu::Normalizer2::getNFCInstance(status);
   DCHECK(U_SUCCESS(status));
   if (U_FAILURE(status))
     return false;
   int32_t utf16_length = static_cast<int32_t>(utf16.length());
   icu::UnicodeString normalized(utf16.data(), utf16_length);
   int32_t normalized_prefix_length =
       normalizer->spanQuickCheckYes(normalized, status);
   if (normalized_prefix_length < utf16_length) {
     icu::UnicodeString un_normalized(normalized, normalized_prefix_length);
     normalized.truncate(normalized_prefix_length);
     normalizer->normalizeSecondAndAppend(normalized, un_normalized, status);
   }
   if (U_FAILURE(status))
     return false;
   normalized.toUTF8String(*result);
   return true;
 }

 }  // namespace base
	// Copyright (c) 2012 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "base/i18n/icu_string_conversions.h"

	#include <stddef.h>
	#include <stdint.h>

	#include <memory>
	#include <vector>

	#include "base/logging.h"
	#include "base/strings/string_util.h"
	#include "base/strings/utf_string_conversions.h"
	#include "third_party/icu/source/common/unicode/normalizer2.h"
	#include "third_party/icu/source/common/unicode/ucnv.h"
	#include "third_party/icu/source/common/unicode/ucnv_cb.h"
	#include "third_party/icu/source/common/unicode/ucnv_err.h"
	#include "third_party/icu/source/common/unicode/ustring.h"

	namespace base {

	namespace {
	// ToUnicodeCallbackSubstitute() is based on UCNV_TO_U_CALLBACK_SUBSTITUTE
	// in source/common/ucnv_err.c.

	// Copyright (c) 1995-2006 International Business Machines Corporation
	// and others
	//
	// All rights reserved.
	//

	// 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, and/or
	// sell copies of the Software, and to permit persons to whom the Software
	// is furnished to do so, provided that the above copyright notice(s) and
	// this permission notice appear in all copies of the Software and that
	// both the above copyright notice(s) and this permission notice appear in
	// supporting documentation.
	//
	// 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
	// OF THIRD PARTY RIGHTS. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS
	// INCLUDED IN THIS NOTICE BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT
	// OR CONSEQUENTIAL DAMAGES, OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
	// OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
	// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE
	// OR PERFORMANCE OF THIS SOFTWARE.
	//
	// Except as contained in this notice, the name of a copyright holder
	// shall not be used in advertising or otherwise to promote the sale, use
	// or other dealings in this Software without prior written authorization
	// of the copyright holder.

	// ___________________________________________________________________________
	//
	// All trademarks and registered trademarks mentioned herein are the property
	// of their respective owners.

	void ToUnicodeCallbackSubstitute(const void* context,
	UConverterToUnicodeArgs *to_args,
	const char* code_units,
	int32_t length,
	UConverterCallbackReason reason,
	UErrorCode * err) {
	static const UChar kReplacementChar = 0xFFFD;
	if (reason <= UCNV_IRREGULAR) {
	if (context == nullptr \|\|
	((reinterpret_cast<const char>(context)) == 'i' &&
	reason == UCNV_UNASSIGNED)) {
	*err = U_ZERO_ERROR;
	ucnv_cbToUWriteUChars(to_args, &kReplacementChar, 1, 0, err);
	}
	// else the caller must have set the error code accordingly.
	}
	// else ignore the reset, close and clone calls.
	}

	bool ConvertFromUTF16(UConverter* converter, const UChar* uchar_src,
	int uchar_len, OnStringConversionError::Type on_error,
	std::string* encoded) {
	int encoded_max_length = UCNV_GET_MAX_BYTES_FOR_STRING(uchar_len,
	ucnv_getMaxCharSize(converter));
	encoded->resize(encoded_max_length);

	UErrorCode status = U_ZERO_ERROR;

	// Setup our error handler.
	switch (on_error) {
	case OnStringConversionError::FAIL:
	ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_STOP, nullptr,
	nullptr, nullptr, &status);
	break;
	case OnStringConversionError::SKIP:
	case OnStringConversionError::SUBSTITUTE:
	ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_SKIP, nullptr,
	nullptr, nullptr, &status);
	break;
	default:
	NOTREACHED();
	}

	// ucnv_fromUChars returns size not including terminating null
	int actual_size = ucnv_fromUChars(converter, &(*encoded)[0],
	encoded_max_length, uchar_src, uchar_len, &status);
	encoded->resize(actual_size);
	ucnv_close(converter);
	if (U_SUCCESS(status))
	return true;
	encoded->clear(); // Make sure the output is empty on error.
	return false;
	}

	// Set up our error handler for ToUTF-16 converters
	void SetUpErrorHandlerForToUChars(OnStringConversionError::Type on_error,
	UConverter* converter, UErrorCode* status) {
	switch (on_error) {
	case OnStringConversionError::FAIL:
	ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_STOP, nullptr, nullptr,
	nullptr, status);
	break;
	case OnStringConversionError::SKIP:
	ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_SKIP, nullptr, nullptr,
	nullptr, status);
	break;
	case OnStringConversionError::SUBSTITUTE:
	ucnv_setToUCallBack(converter, ToUnicodeCallbackSubstitute, nullptr,
	nullptr, nullptr, status);
	break;
	default:
	NOTREACHED();
	}
	}

	} // namespace

	// Codepage <-> Wide/UTF-16 ---------------------------------------------------

	bool UTF16ToCodepage(const string16& utf16,
	const char* codepage_name,
	OnStringConversionError::Type on_error,
	std::string* encoded) {
	encoded->clear();

	UErrorCode status = U_ZERO_ERROR;
	UConverter* converter = ucnv_open(codepage_name, &status);
	if (!U_SUCCESS(status))
	return false;

	return ConvertFromUTF16(converter, utf16.c_str(),
	static_cast<int>(utf16.length()), on_error, encoded);
	}

	bool CodepageToUTF16(const std::string& encoded,
	const char* codepage_name,
	OnStringConversionError::Type on_error,
	string16* utf16) {
	utf16->clear();

	UErrorCode status = U_ZERO_ERROR;
	UConverter* converter = ucnv_open(codepage_name, &status);
	if (!U_SUCCESS(status))
	return false;

	// Even in the worst case, the maximum length in 2-byte units of UTF-16
	// output would be at most the same as the number of bytes in input. There
	// is no single-byte encoding in which a character is mapped to a
	// non-BMP character requiring two 2-byte units.
	//
	// Moreover, non-BMP characters in legacy multibyte encodings
	// (e.g. EUC-JP, GB18030) take at least 2 bytes. The only exceptions are
	// BOCU and SCSU, but we don't care about them.
	size_t uchar_max_length = encoded.length() + 1;

	SetUpErrorHandlerForToUChars(on_error, converter, &status);
	std::unique_ptr<char16[]> buffer(new char16[uchar_max_length]);
	int actual_size = ucnv_toUChars(converter, buffer.get(),
	static_cast<int>(uchar_max_length), encoded.data(),
	static_cast<int>(encoded.length()), &status);
	ucnv_close(converter);
	if (!U_SUCCESS(status)) {
	utf16->clear(); // Make sure the output is empty on error.
	return false;
	}

	utf16->assign(buffer.get(), actual_size);
	return true;
	}

	bool ConvertToUtf8AndNormalize(const std::string& text,
	const std::string& charset,
	std::string* result) {
	result->clear();
	string16 utf16;
	if (!CodepageToUTF16(
	text, charset.c_str(), OnStringConversionError::FAIL, &utf16))
	return false;

	UErrorCode status = U_ZERO_ERROR;
	const icu::Normalizer2* normalizer = icu::Normalizer2::getNFCInstance(status);
	DCHECK(U_SUCCESS(status));
	if (U_FAILURE(status))
	return false;
	int32_t utf16_length = static_cast<int32_t>(utf16.length());
	icu::UnicodeString normalized(utf16.data(), utf16_length);
	int32_t normalized_prefix_length =
	normalizer->spanQuickCheckYes(normalized, status);
	if (normalized_prefix_length < utf16_length) {
	icu::UnicodeString un_normalized(normalized, normalized_prefix_length);
	normalized.truncate(normalized_prefix_length);
	normalizer->normalizeSecondAndAppend(normalized, un_normalized, status);
	}
	if (U_FAILURE(status))
	return false;
	normalized.toUTF8String(*result);
	return true;
	}

	} // namespace base