diff options
| -rw-r--r-- | base/base.gyp | 2 | ||||
| -rw-r--r-- | base/i18n/string_conversions.cc | 626 | ||||
| -rw-r--r-- | base/i18n/string_conversions.h | 101 | ||||
| -rw-r--r-- | base/string_util.h | 92 | ||||
| -rw-r--r-- | base/string_util_icu.cc | 613 |
5 files changed, 733 insertions, 701 deletions
diff --git a/base/base.gyp b/base/base.gyp index 7ea2bd9..757f5e2 100644 --- a/base/base.gyp +++ b/base/base.gyp @@ -144,6 +144,8 @@ 'hmac_mac.cc', 'hmac_nss.cc', 'hmac_win.cc', + 'i18n/string_conversions.cc', + 'i18n/string_conversions.h', 'iat_patch.cc', 'iat_patch.h', 'icu_util.cc', diff --git a/base/i18n/string_conversions.cc b/base/i18n/string_conversions.cc new file mode 100644 index 0000000..35c9d6d --- /dev/null +++ b/base/i18n/string_conversions.cc @@ -0,0 +1,626 @@ +// Copyright (c) 2009 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/string_conversions.h" + +#include <vector> + +#include "base/basictypes.h" +#include "base/logging.h" +#include "base/string_util.h" +#include "unicode/ucnv.h" +#include "unicode/ucnv_cb.h" +#include "unicode/ucnv_err.h" +#include "unicode/ustring.h" + +namespace { + +inline bool IsValidCodepoint(uint32 code_point) { + // Excludes the surrogate code points ([0xD800, 0xDFFF]) and + // codepoints larger than 0x10FFFF (the highest codepoint allowed). + // Non-characters and unassigned codepoints are allowed. + return code_point < 0xD800u || + (code_point >= 0xE000u && code_point <= 0x10FFFFu); +} + +// ToUnicodeCallbackSubstitute() is based on UCNV_TO_U_CALLBACK_SUSBSTITUTE +// 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 == NULL || + (*(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. +} + +// ReadUnicodeCharacter -------------------------------------------------------- + +// Reads a UTF-8 stream, placing the next code point into the given output +// |*code_point|. |src| represents the entire string to read, and |*char_index| +// is the character offset within the string to start reading at. |*char_index| +// will be updated to index the last character read, such that incrementing it +// (as in a for loop) will take the reader to the next character. +// +// Returns true on success. On false, |*code_point| will be invalid. +bool ReadUnicodeCharacter(const char* src, int32 src_len, + int32* char_index, uint32* code_point_out) { + // U8_NEXT expects to be able to use -1 to signal an error, so we must + // use a signed type for code_point. But this function returns false + // on error anyway, so code_point_out is unsigned. + int32 code_point; + U8_NEXT(src, *char_index, src_len, code_point); + *code_point_out = static_cast<uint32>(code_point); + + // The ICU macro above moves to the next char, we want to point to the last + // char consumed. + (*char_index)--; + + // Validate the decoded value. + return IsValidCodepoint(code_point); +} + +// Reads a UTF-16 character. The usage is the same as the 8-bit version above. +bool ReadUnicodeCharacter(const char16* src, int32 src_len, + int32* char_index, uint32* code_point) { + if (U16_IS_SURROGATE(src[*char_index])) { + if (!U16_IS_SURROGATE_LEAD(src[*char_index]) || + *char_index + 1 >= src_len || + !U16_IS_TRAIL(src[*char_index + 1])) { + // Invalid surrogate pair. + return false; + } + + // Valid surrogate pair. + *code_point = U16_GET_SUPPLEMENTARY(src[*char_index], + src[*char_index + 1]); + (*char_index)++; + } else { + // Not a surrogate, just one 16-bit word. + *code_point = src[*char_index]; + } + + return IsValidCodepoint(*code_point); +} + +#if defined(WCHAR_T_IS_UTF32) +// Reads UTF-32 character. The usage is the same as the 8-bit version above. +bool ReadUnicodeCharacter(const wchar_t* src, int32 src_len, + int32* char_index, uint32* code_point) { + // Conversion is easy since the source is 32-bit. + *code_point = src[*char_index]; + + // Validate the value. + return IsValidCodepoint(*code_point); +} +#endif // defined(WCHAR_T_IS_UTF32) + +// WriteUnicodeCharacter ------------------------------------------------------- + +// Appends a UTF-8 character to the given 8-bit string. +void WriteUnicodeCharacter(uint32 code_point, std::string* output) { + if (code_point <= 0x7f) { + // Fast path the common case of one byte. + output->push_back(code_point); + return; + } + + // U8_APPEND_UNSAFE can append up to 4 bytes. + int32 char_offset = static_cast<int32>(output->length()); + output->resize(char_offset + U8_MAX_LENGTH); + + U8_APPEND_UNSAFE(&(*output)[0], char_offset, code_point); + + // U8_APPEND_UNSAFE will advance our pointer past the inserted character, so + // it will represent the new length of the string. + output->resize(char_offset); +} + +// Appends the given code point as a UTF-16 character to the STL string. +void WriteUnicodeCharacter(uint32 code_point, string16* output) { + if (U16_LENGTH(code_point) == 1) { + // Thie code point is in the Basic Multilingual Plane (BMP). + output->push_back(static_cast<char16>(code_point)); + } else { + // Non-BMP characters use a double-character encoding. + int32 char_offset = static_cast<int32>(output->length()); + output->resize(char_offset + U16_MAX_LENGTH); + U16_APPEND_UNSAFE(&(*output)[0], char_offset, code_point); + } +} + +#if defined(WCHAR_T_IS_UTF32) +// Appends the given UTF-32 character to the given 32-bit string. +inline void WriteUnicodeCharacter(uint32 code_point, std::wstring* output) { + // This is the easy case, just append the character. + output->push_back(code_point); +} +#endif // defined(WCHAR_T_IS_UTF32) + +// Generalized Unicode converter ----------------------------------------------- + +// Converts the given source Unicode character type to the given destination +// Unicode character type as a STL string. The given input buffer and size +// determine the source, and the given output STL string will be replaced by +// the result. +template<typename SRC_CHAR, typename DEST_STRING> +bool ConvertUnicode(const SRC_CHAR* src, size_t src_len, DEST_STRING* output) { + output->clear(); + + // ICU requires 32-bit numbers. + bool success = true; + int32 src_len32 = static_cast<int32>(src_len); + for (int32 i = 0; i < src_len32; i++) { + uint32 code_point; + if (ReadUnicodeCharacter(src, src_len32, &i, &code_point)) { + WriteUnicodeCharacter(code_point, output); + } else { + // TODO(jungshik): consider adding 'Replacement character' (U+FFFD) + // in place of an invalid codepoint. + success = false; + } + } + return success; +} + + +// Guesses the length of the output in UTF-8 in bytes, and reserves that amount +// of space in the given string. We also assume that the input character types +// are unsigned, which will be true for UTF-16 and -32 on our systems. We assume +// the string length is greater than zero. +template<typename CHAR> +void ReserveUTF8Output(const CHAR* src, size_t src_len, std::string* output) { + if (src[0] < 0x80) { + // Assume that the entire input will be ASCII. + output->reserve(src_len); + } else { + // Assume that the entire input is non-ASCII and will have 3 bytes per char. + output->reserve(src_len * 3); + } +} + +// Guesses the size of the output buffer (containing either UTF-16 or -32 data) +// given some UTF-8 input that will be converted to it. See ReserveUTF8Output. +// We assume the source length is > 0. +template<typename STRING> +void ReserveUTF16Or32Output(const char* src, size_t src_len, STRING* output) { + if (static_cast<unsigned char>(src[0]) < 0x80) { + // Assume the input is all ASCII, which means 1:1 correspondence. + output->reserve(src_len); + } else { + // Otherwise assume that the UTF-8 sequences will have 2 bytes for each + // character. + output->reserve(src_len / 2); + } +} + +bool ConvertFromUTF16(UConverter* converter, const UChar* uchar_src, + int uchar_len, OnStringUtilConversionError::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 OnStringUtilConversionError::FAIL: + ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_STOP, 0, + NULL, NULL, &status); + break; + case OnStringUtilConversionError::SKIP: + case OnStringUtilConversionError::SUBSTITUTE: + ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_SKIP, 0, + NULL, NULL, &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(OnStringUtilConversionError::Type on_error, + UConverter* converter, UErrorCode* status) { + switch (on_error) { + case OnStringUtilConversionError::FAIL: + ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_STOP, 0, + NULL, NULL, status); + break; + case OnStringUtilConversionError::SKIP: + ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_SKIP, 0, + NULL, NULL, status); + break; + case OnStringUtilConversionError::SUBSTITUTE: + ucnv_setToUCallBack(converter, ToUnicodeCallbackSubstitute, 0, + NULL, NULL, status); + break; + default: + NOTREACHED(); + } +} + +inline UConverterType utf32_platform_endian() { +#if U_IS_BIG_ENDIAN + return UCNV_UTF32_BigEndian; +#else + return UCNV_UTF32_LittleEndian; +#endif +} + +} // namespace + +// UTF-8 <-> Wide -------------------------------------------------------------- + +std::string WideToUTF8(const std::wstring& wide) { + std::string ret; + if (wide.empty()) + return ret; + + // Ignore the success flag of this call, it will do the best it can for + // invalid input, which is what we want here. + WideToUTF8(wide.data(), wide.length(), &ret); + return ret; +} + +bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output) { + if (src_len == 0) { + output->clear(); + return true; + } + + ReserveUTF8Output(src, src_len, output); + return ConvertUnicode<wchar_t, std::string>(src, src_len, output); +} + +std::wstring UTF8ToWide(const base::StringPiece& utf8) { + std::wstring ret; + if (utf8.empty()) + return ret; + + UTF8ToWide(utf8.data(), utf8.length(), &ret); + return ret; +} + +bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output) { + if (src_len == 0) { + output->clear(); + return true; + } + + ReserveUTF16Or32Output(src, src_len, output); + return ConvertUnicode<char, std::wstring>(src, src_len, output); +} + +// UTF-16 <-> Wide ------------------------------------------------------------- + +#if defined(WCHAR_T_IS_UTF16) + +// When wide == UTF-16, then conversions are a NOP. +string16 WideToUTF16(const std::wstring& wide) { + return wide; +} + +bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output) { + output->assign(src, src_len); + return true; +} + +std::wstring UTF16ToWide(const string16& utf16) { + return utf16; +} + +bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output) { + output->assign(src, src_len); + return true; +} + +#elif defined(WCHAR_T_IS_UTF32) + +string16 WideToUTF16(const std::wstring& wide) { + string16 ret; + if (wide.empty()) + return ret; + + WideToUTF16(wide.data(), wide.length(), &ret); + return ret; +} + +bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output) { + if (src_len == 0) { + output->clear(); + return true; + } + + // Assume that normally we won't have any non-BMP characters so the counts + // will be the same. + output->reserve(src_len); + return ConvertUnicode<wchar_t, string16>(src, src_len, output); +} + +std::wstring UTF16ToWide(const string16& utf16) { + std::wstring ret; + if (utf16.empty()) + return ret; + + UTF16ToWide(utf16.data(), utf16.length(), &ret); + return ret; +} + +bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output) { + if (src_len == 0) { + output->clear(); + return true; + } + + // Assume that normally we won't have any non-BMP characters so the counts + // will be the same. + output->reserve(src_len); + return ConvertUnicode<char16, std::wstring>(src, src_len, output); +} + +#endif // defined(WCHAR_T_IS_UTF32) + +// UTF16 <-> UTF8 -------------------------------------------------------------- + +#if defined(WCHAR_T_IS_UTF32) + +bool UTF8ToUTF16(const char* src, size_t src_len, string16* output) { + if (src_len == 0) { + output->clear(); + return true; + } + + ReserveUTF16Or32Output(src, src_len, output); + return ConvertUnicode<char, string16>(src, src_len, output); +} + +string16 UTF8ToUTF16(const std::string& utf8) { + string16 ret; + if (utf8.empty()) + return ret; + + // Ignore the success flag of this call, it will do the best it can for + // invalid input, which is what we want here. + UTF8ToUTF16(utf8.data(), utf8.length(), &ret); + return ret; +} + +bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output) { + if (src_len == 0) { + output->clear(); + return true; + } + + ReserveUTF8Output(src, src_len, output); + return ConvertUnicode<char16, std::string>(src, src_len, output); +} + +std::string UTF16ToUTF8(const string16& utf16) { + std::string ret; + if (utf16.empty()) + return ret; + + // Ignore the success flag of this call, it will do the best it can for + // invalid input, which is what we want here. + UTF16ToUTF8(utf16.data(), utf16.length(), &ret); + return ret; +} + +#elif defined(WCHAR_T_IS_UTF16) +// Easy case since we can use the "wide" versions we already wrote above. + +bool UTF8ToUTF16(const char* src, size_t src_len, string16* output) { + return UTF8ToWide(src, src_len, output); +} + +string16 UTF8ToUTF16(const std::string& utf8) { + return UTF8ToWide(utf8); +} + +bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output) { + return WideToUTF8(src, src_len, output); +} + +std::string UTF16ToUTF8(const string16& utf16) { + return WideToUTF8(utf16); +} + +#endif + +// Codepage <-> Wide/UTF-16 --------------------------------------------------- + +// Convert a wstring into the specified codepage_name. If the codepage +// isn't found, return false. +bool WideToCodepage(const std::wstring& wide, + const char* codepage_name, + OnStringUtilConversionError::Type on_error, + std::string* encoded) { +#if defined(WCHAR_T_IS_UTF16) + return UTF16ToCodepage(wide, codepage_name, on_error, encoded); +#elif defined(WCHAR_T_IS_UTF32) + encoded->clear(); + + UErrorCode status = U_ZERO_ERROR; + UConverter* converter = ucnv_open(codepage_name, &status); + if (!U_SUCCESS(status)) + return false; + + int utf16_len; + // When wchar_t is wider than UChar (16 bits), transform |wide| into a + // UChar* string. Size the UChar* buffer to be large enough to hold twice + // as many UTF-16 code units (UChar's) as there are Unicode code points, + // in case each code points translates to a UTF-16 surrogate pair, + // and leave room for a NUL terminator. + std::vector<UChar> utf16(wide.length() * 2 + 1); + u_strFromWCS(&utf16[0], utf16.size(), &utf16_len, + wide.c_str(), wide.length(), &status); + DCHECK(U_SUCCESS(status)) << "failed to convert wstring to UChar*"; + + return ConvertFromUTF16(converter, &utf16[0], utf16_len, on_error, encoded); +#endif // defined(WCHAR_T_IS_UTF32) +} + +// Convert a UTF-16 string into the specified codepage_name. If the codepage +// isn't found, return false. +bool UTF16ToCodepage(const string16& utf16, + const char* codepage_name, + OnStringUtilConversionError::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); +} + +// Converts a string of the given codepage into wstring. +// If the codepage isn't found, return false. +bool CodepageToWide(const std::string& encoded, + const char* codepage_name, + OnStringUtilConversionError::Type on_error, + std::wstring* wide) { +#if defined(WCHAR_T_IS_UTF16) + return CodepageToUTF16(encoded, codepage_name, on_error, wide); +#elif defined(WCHAR_T_IS_UTF32) + wide->clear(); + + UErrorCode status = U_ZERO_ERROR; + UConverter* converter = ucnv_open(codepage_name, &status); + if (!U_SUCCESS(status)) + return false; + + // The maximum length in 4 byte unit of UTF-32 output would be + // at most the same as the number of bytes in input. In the worst + // case of GB18030 (excluding escaped-based encodings like ISO-2022-JP), + // this can be 4 times larger than actually needed. + size_t wchar_max_length = encoded.length() + 1; + + // The byte buffer and its length to pass to ucnv_toAlgorithimic. + char* byte_buffer = reinterpret_cast<char*>( + WriteInto(wide, wchar_max_length)); + int byte_buffer_length = static_cast<int>(wchar_max_length) * 4; + + SetUpErrorHandlerForToUChars(on_error, converter, &status); + int actual_size = ucnv_toAlgorithmic(utf32_platform_endian(), + converter, + byte_buffer, + byte_buffer_length, + encoded.data(), + static_cast<int>(encoded.length()), + &status); + ucnv_close(converter); + + if (!U_SUCCESS(status)) { + wide->clear(); // Make sure the output is empty on error. + return false; + } + + // actual_size is # of bytes. + wide->resize(actual_size / 4); + return true; +#endif // defined(WCHAR_T_IS_UTF32) +} + +// Converts a string of the given codepage into UTF-16. +// If the codepage isn't found, return false. +bool CodepageToUTF16(const std::string& encoded, + const char* codepage_name, + OnStringUtilConversionError::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); + int actual_size = ucnv_toUChars(converter, + WriteInto(utf16, uchar_max_length), + 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->resize(actual_size); + return true; +} + diff --git a/base/i18n/string_conversions.h b/base/i18n/string_conversions.h new file mode 100644 index 0000000..c055bb1 --- /dev/null +++ b/base/i18n/string_conversions.h @@ -0,0 +1,101 @@ +// Copyright (c) 2009 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. + +#ifndef BASE_I18N_STRING_CONVERSIONS_H_ +#define BASE_I18N_STRING_CONVERSIONS_H_ + +#include <string> + +#include "base/string16.h" +#include "base/string_piece.h" + +// These convert between UTF-8, -16, and -32 strings. They are potentially slow, +// so avoid unnecessary conversions. The low-level versions return a boolean +// indicating whether the conversion was 100% valid. In this case, it will still +// do the best it can and put the result in the output buffer. The versions that +// return strings ignore this error and just return the best conversion +// possible. +// +// Note that only the structural validity is checked and non-character +// codepoints and unassigned are regarded as valid. +// TODO(jungshik): Consider replacing an invalid input sequence with +// the Unicode replacement character or adding |replacement_char| parameter. +// Currently, it's skipped in the ouput, which could be problematic in +// some situations. +bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output); +std::string WideToUTF8(const std::wstring& wide); +bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output); +std::wstring UTF8ToWide(const base::StringPiece& utf8); + +bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output); +string16 WideToUTF16(const std::wstring& wide); +bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output); +std::wstring UTF16ToWide(const string16& utf16); + +bool UTF8ToUTF16(const char* src, size_t src_len, string16* output); +string16 UTF8ToUTF16(const std::string& utf8); +bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output); +std::string UTF16ToUTF8(const string16& utf16); + +// We are trying to get rid of wstring as much as possible, but it's too big +// a mess to do it all at once. These conversions should be used when we +// really should just be passing a string16 around, but we haven't finished +// porting whatever module uses wstring and the conversion is being used as a +// stopcock. This makes it easy to grep for the ones that should be removed. +#if defined(OS_WIN) +# define WideToUTF16Hack +# define UTF16ToWideHack +#else +# define WideToUTF16Hack WideToUTF16 +# define UTF16ToWideHack UTF16ToWide +#endif + +// Defines the error handling modes of UTF16ToCodepage, CodepageToUTF16, +// WideToCodepage and CodepageToWide. +class OnStringUtilConversionError { + public: + enum Type { + // The function will return failure. The output buffer will be empty. + FAIL, + + // The offending characters are skipped and the conversion will proceed as + // if they did not exist. + SKIP, + + // When converting to Unicode, the offending byte sequences are substituted + // by Unicode replacement character (U+FFFD). When converting from Unicode, + // this is the same as SKIP. + SUBSTITUTE, + }; + + private: + OnStringUtilConversionError(); +}; + +// Converts between UTF-16 strings and the encoding specified. If the +// encoding doesn't exist or the encoding fails (when on_error is FAIL), +// returns false. +bool UTF16ToCodepage(const string16& utf16, + const char* codepage_name, + OnStringUtilConversionError::Type on_error, + std::string* encoded); + +bool CodepageToUTF16(const std::string& encoded, + const char* codepage_name, + OnStringUtilConversionError::Type on_error, + string16* utf16); + +// Converts between wide strings and the encoding specified. If the +// encoding doesn't exist or the encoding fails (when on_error is FAIL), +// returns false. +bool WideToCodepage(const std::wstring& wide, + const char* codepage_name, + OnStringUtilConversionError::Type on_error, + std::string* encoded); +bool CodepageToWide(const std::string& encoded, + const char* codepage_name, + OnStringUtilConversionError::Type on_error, + std::wstring* wide); + +#endif // BASE_I18N_STRING_CONVERSIONS_H_ diff --git a/base/string_util.h b/base/string_util.h index 64c1f60..52c2a84 100644 --- a/base/string_util.h +++ b/base/string_util.h @@ -16,6 +16,10 @@ #include "base/string16.h" #include "base/string_piece.h" // For implicit conversions. +// TODO(brettw) this dependency should be removed and callers that need +// these functions should include this file directly. +#include "base/i18n/string_conversions.h" + // Safe standard library wrappers for all platforms. namespace base { @@ -180,94 +184,6 @@ std::wstring ASCIIToWide(const base::StringPiece& ascii); std::string UTF16ToASCII(const string16& utf16); string16 ASCIIToUTF16(const base::StringPiece& ascii); -// These convert between UTF-8, -16, and -32 strings. They are potentially slow, -// so avoid unnecessary conversions. The low-level versions return a boolean -// indicating whether the conversion was 100% valid. In this case, it will still -// do the best it can and put the result in the output buffer. The versions that -// return strings ignore this error and just return the best conversion -// possible. -// -// Note that only the structural validity is checked and non-character -// codepoints and unassigned are regarded as valid. -// TODO(jungshik): Consider replacing an invalid input sequence with -// the Unicode replacement character or adding |replacement_char| parameter. -// Currently, it's skipped in the ouput, which could be problematic in -// some situations. -bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output); -std::string WideToUTF8(const std::wstring& wide); -bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output); -std::wstring UTF8ToWide(const base::StringPiece& utf8); - -bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output); -string16 WideToUTF16(const std::wstring& wide); -bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output); -std::wstring UTF16ToWide(const string16& utf16); - -bool UTF8ToUTF16(const char* src, size_t src_len, string16* output); -string16 UTF8ToUTF16(const std::string& utf8); -bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output); -std::string UTF16ToUTF8(const string16& utf16); - -// We are trying to get rid of wstring as much as possible, but it's too big -// a mess to do it all at once. These conversions should be used when we -// really should just be passing a string16 around, but we haven't finished -// porting whatever module uses wstring and the conversion is being used as a -// stopcock. This makes it easy to grep for the ones that should be removed. -#if defined(OS_WIN) -# define WideToUTF16Hack -# define UTF16ToWideHack -#else -# define WideToUTF16Hack WideToUTF16 -# define UTF16ToWideHack UTF16ToWide -#endif - -// Defines the error handling modes of UTF16ToCodepage, CodepageToUTF16, -// WideToCodepage and CodepageToWide. -class OnStringUtilConversionError { - public: - enum Type { - // The function will return failure. The output buffer will be empty. - FAIL, - - // The offending characters are skipped and the conversion will proceed as - // if they did not exist. - SKIP, - - // When converting to Unicode, the offending byte sequences are substituted - // by Unicode replacement character (U+FFFD). When converting from Unicode, - // this is the same as SKIP. - SUBSTITUTE, - }; - - private: - OnStringUtilConversionError(); -}; - -// Converts between UTF-16 strings and the encoding specified. If the -// encoding doesn't exist or the encoding fails (when on_error is FAIL), -// returns false. -bool UTF16ToCodepage(const string16& utf16, - const char* codepage_name, - OnStringUtilConversionError::Type on_error, - std::string* encoded); - -bool CodepageToUTF16(const std::string& encoded, - const char* codepage_name, - OnStringUtilConversionError::Type on_error, - string16* utf16); - -// Converts between wide strings and the encoding specified. If the -// encoding doesn't exist or the encoding fails (when on_error is FAIL), -// returns false. -bool WideToCodepage(const std::wstring& wide, - const char* codepage_name, - OnStringUtilConversionError::Type on_error, - std::string* encoded); -bool CodepageToWide(const std::string& encoded, - const char* codepage_name, - OnStringUtilConversionError::Type on_error, - std::wstring* wide); - // Converts the given wide string to the corresponding Latin1. This will fail // (return false) if any characters are more than 255. bool WideToLatin1(const std::wstring& wide, std::string* latin1); diff --git a/base/string_util_icu.cc b/base/string_util_icu.cc index d3c9edf..68fbd10 100644 --- a/base/string_util_icu.cc +++ b/base/string_util_icu.cc @@ -11,621 +11,8 @@ #include "base/logging.h" #include "base/singleton.h" #include "unicode/numfmt.h" -#include "unicode/ucnv.h" -#include "unicode/ucnv_cb.h" -#include "unicode/ucnv_err.h" #include "unicode/ustring.h" -namespace { - -inline bool IsValidCodepoint(uint32 code_point) { - // Excludes the surrogate code points ([0xD800, 0xDFFF]) and - // codepoints larger than 0x10FFFF (the highest codepoint allowed). - // Non-characters and unassigned codepoints are allowed. - return code_point < 0xD800u || - (code_point >= 0xE000u && code_point <= 0x10FFFFu); -} - -// ToUnicodeCallbackSubstitute() is based on UCNV_TO_U_CALLBACK_SUSBSTITUTE -// 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 == NULL || - (*(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. -} - -// ReadUnicodeCharacter -------------------------------------------------------- - -// Reads a UTF-8 stream, placing the next code point into the given output -// |*code_point|. |src| represents the entire string to read, and |*char_index| -// is the character offset within the string to start reading at. |*char_index| -// will be updated to index the last character read, such that incrementing it -// (as in a for loop) will take the reader to the next character. -// -// Returns true on success. On false, |*code_point| will be invalid. -bool ReadUnicodeCharacter(const char* src, int32 src_len, - int32* char_index, uint32* code_point_out) { - // U8_NEXT expects to be able to use -1 to signal an error, so we must - // use a signed type for code_point. But this function returns false - // on error anyway, so code_point_out is unsigned. - int32 code_point; - U8_NEXT(src, *char_index, src_len, code_point); - *code_point_out = static_cast<uint32>(code_point); - - // The ICU macro above moves to the next char, we want to point to the last - // char consumed. - (*char_index)--; - - // Validate the decoded value. - return IsValidCodepoint(code_point); -} - -// Reads a UTF-16 character. The usage is the same as the 8-bit version above. -bool ReadUnicodeCharacter(const char16* src, int32 src_len, - int32* char_index, uint32* code_point) { - if (U16_IS_SURROGATE(src[*char_index])) { - if (!U16_IS_SURROGATE_LEAD(src[*char_index]) || - *char_index + 1 >= src_len || - !U16_IS_TRAIL(src[*char_index + 1])) { - // Invalid surrogate pair. - return false; - } - - // Valid surrogate pair. - *code_point = U16_GET_SUPPLEMENTARY(src[*char_index], - src[*char_index + 1]); - (*char_index)++; - } else { - // Not a surrogate, just one 16-bit word. - *code_point = src[*char_index]; - } - - return IsValidCodepoint(*code_point); -} - -#if defined(WCHAR_T_IS_UTF32) -// Reads UTF-32 character. The usage is the same as the 8-bit version above. -bool ReadUnicodeCharacter(const wchar_t* src, int32 src_len, - int32* char_index, uint32* code_point) { - // Conversion is easy since the source is 32-bit. - *code_point = src[*char_index]; - - // Validate the value. - return IsValidCodepoint(*code_point); -} -#endif // defined(WCHAR_T_IS_UTF32) - -// WriteUnicodeCharacter ------------------------------------------------------- - -// Appends a UTF-8 character to the given 8-bit string. -void WriteUnicodeCharacter(uint32 code_point, std::string* output) { - if (code_point <= 0x7f) { - // Fast path the common case of one byte. - output->push_back(code_point); - return; - } - - // U8_APPEND_UNSAFE can append up to 4 bytes. - int32 char_offset = static_cast<int32>(output->length()); - output->resize(char_offset + U8_MAX_LENGTH); - - U8_APPEND_UNSAFE(&(*output)[0], char_offset, code_point); - - // U8_APPEND_UNSAFE will advance our pointer past the inserted character, so - // it will represent the new length of the string. - output->resize(char_offset); -} - -// Appends the given code point as a UTF-16 character to the STL string. -void WriteUnicodeCharacter(uint32 code_point, string16* output) { - if (U16_LENGTH(code_point) == 1) { - // Thie code point is in the Basic Multilingual Plane (BMP). - output->push_back(static_cast<char16>(code_point)); - } else { - // Non-BMP characters use a double-character encoding. - int32 char_offset = static_cast<int32>(output->length()); - output->resize(char_offset + U16_MAX_LENGTH); - U16_APPEND_UNSAFE(&(*output)[0], char_offset, code_point); - } -} - -#if defined(WCHAR_T_IS_UTF32) -// Appends the given UTF-32 character to the given 32-bit string. -inline void WriteUnicodeCharacter(uint32 code_point, std::wstring* output) { - // This is the easy case, just append the character. - output->push_back(code_point); -} -#endif // defined(WCHAR_T_IS_UTF32) - -// Generalized Unicode converter ----------------------------------------------- - -// Converts the given source Unicode character type to the given destination -// Unicode character type as a STL string. The given input buffer and size -// determine the source, and the given output STL string will be replaced by -// the result. -template<typename SRC_CHAR, typename DEST_STRING> -bool ConvertUnicode(const SRC_CHAR* src, size_t src_len, DEST_STRING* output) { - output->clear(); - - // ICU requires 32-bit numbers. - bool success = true; - int32 src_len32 = static_cast<int32>(src_len); - for (int32 i = 0; i < src_len32; i++) { - uint32 code_point; - if (ReadUnicodeCharacter(src, src_len32, &i, &code_point)) { - WriteUnicodeCharacter(code_point, output); - } else { - // TODO(jungshik): consider adding 'Replacement character' (U+FFFD) - // in place of an invalid codepoint. - success = false; - } - } - return success; -} - - -// Guesses the length of the output in UTF-8 in bytes, and reserves that amount -// of space in the given string. We also assume that the input character types -// are unsigned, which will be true for UTF-16 and -32 on our systems. We assume -// the string length is greater than zero. -template<typename CHAR> -void ReserveUTF8Output(const CHAR* src, size_t src_len, std::string* output) { - if (src[0] < 0x80) { - // Assume that the entire input will be ASCII. - output->reserve(src_len); - } else { - // Assume that the entire input is non-ASCII and will have 3 bytes per char. - output->reserve(src_len * 3); - } -} - -// Guesses the size of the output buffer (containing either UTF-16 or -32 data) -// given some UTF-8 input that will be converted to it. See ReserveUTF8Output. -// We assume the source length is > 0. -template<typename STRING> -void ReserveUTF16Or32Output(const char* src, size_t src_len, STRING* output) { - if (static_cast<unsigned char>(src[0]) < 0x80) { - // Assume the input is all ASCII, which means 1:1 correspondence. - output->reserve(src_len); - } else { - // Otherwise assume that the UTF-8 sequences will have 2 bytes for each - // character. - output->reserve(src_len / 2); - } -} - -bool ConvertFromUTF16(UConverter* converter, const UChar* uchar_src, - int uchar_len, OnStringUtilConversionError::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 OnStringUtilConversionError::FAIL: - ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_STOP, 0, - NULL, NULL, &status); - break; - case OnStringUtilConversionError::SKIP: - case OnStringUtilConversionError::SUBSTITUTE: - ucnv_setFromUCallBack(converter, UCNV_FROM_U_CALLBACK_SKIP, 0, - NULL, NULL, &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(OnStringUtilConversionError::Type on_error, - UConverter* converter, UErrorCode* status) { - switch (on_error) { - case OnStringUtilConversionError::FAIL: - ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_STOP, 0, - NULL, NULL, status); - break; - case OnStringUtilConversionError::SKIP: - ucnv_setToUCallBack(converter, UCNV_TO_U_CALLBACK_SKIP, 0, - NULL, NULL, status); - break; - case OnStringUtilConversionError::SUBSTITUTE: - ucnv_setToUCallBack(converter, ToUnicodeCallbackSubstitute, 0, - NULL, NULL, status); - break; - default: - NOTREACHED(); - } -} - -inline UConverterType utf32_platform_endian() { -#if U_IS_BIG_ENDIAN - return UCNV_UTF32_BigEndian; -#else - return UCNV_UTF32_LittleEndian; -#endif -} - -} // namespace - -// UTF-8 <-> Wide -------------------------------------------------------------- - -std::string WideToUTF8(const std::wstring& wide) { - std::string ret; - if (wide.empty()) - return ret; - - // Ignore the success flag of this call, it will do the best it can for - // invalid input, which is what we want here. - WideToUTF8(wide.data(), wide.length(), &ret); - return ret; -} - -bool WideToUTF8(const wchar_t* src, size_t src_len, std::string* output) { - if (src_len == 0) { - output->clear(); - return true; - } - - ReserveUTF8Output(src, src_len, output); - return ConvertUnicode<wchar_t, std::string>(src, src_len, output); -} - -std::wstring UTF8ToWide(const base::StringPiece& utf8) { - std::wstring ret; - if (utf8.empty()) - return ret; - - UTF8ToWide(utf8.data(), utf8.length(), &ret); - return ret; -} - -bool UTF8ToWide(const char* src, size_t src_len, std::wstring* output) { - if (src_len == 0) { - output->clear(); - return true; - } - - ReserveUTF16Or32Output(src, src_len, output); - return ConvertUnicode<char, std::wstring>(src, src_len, output); -} - -// UTF-16 <-> Wide ------------------------------------------------------------- - -#if defined(WCHAR_T_IS_UTF16) - -// When wide == UTF-16, then conversions are a NOP. -string16 WideToUTF16(const std::wstring& wide) { - return wide; -} - -bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output) { - output->assign(src, src_len); - return true; -} - -std::wstring UTF16ToWide(const string16& utf16) { - return utf16; -} - -bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output) { - output->assign(src, src_len); - return true; -} - -#elif defined(WCHAR_T_IS_UTF32) - -string16 WideToUTF16(const std::wstring& wide) { - string16 ret; - if (wide.empty()) - return ret; - - WideToUTF16(wide.data(), wide.length(), &ret); - return ret; -} - -bool WideToUTF16(const wchar_t* src, size_t src_len, string16* output) { - if (src_len == 0) { - output->clear(); - return true; - } - - // Assume that normally we won't have any non-BMP characters so the counts - // will be the same. - output->reserve(src_len); - return ConvertUnicode<wchar_t, string16>(src, src_len, output); -} - -std::wstring UTF16ToWide(const string16& utf16) { - std::wstring ret; - if (utf16.empty()) - return ret; - - UTF16ToWide(utf16.data(), utf16.length(), &ret); - return ret; -} - -bool UTF16ToWide(const char16* src, size_t src_len, std::wstring* output) { - if (src_len == 0) { - output->clear(); - return true; - } - - // Assume that normally we won't have any non-BMP characters so the counts - // will be the same. - output->reserve(src_len); - return ConvertUnicode<char16, std::wstring>(src, src_len, output); -} - -#endif // defined(WCHAR_T_IS_UTF32) - -// UTF16 <-> UTF8 -------------------------------------------------------------- - -#if defined(WCHAR_T_IS_UTF32) - -bool UTF8ToUTF16(const char* src, size_t src_len, string16* output) { - if (src_len == 0) { - output->clear(); - return true; - } - - ReserveUTF16Or32Output(src, src_len, output); - return ConvertUnicode<char, string16>(src, src_len, output); -} - -string16 UTF8ToUTF16(const std::string& utf8) { - string16 ret; - if (utf8.empty()) - return ret; - - // Ignore the success flag of this call, it will do the best it can for - // invalid input, which is what we want here. - UTF8ToUTF16(utf8.data(), utf8.length(), &ret); - return ret; -} - -bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output) { - if (src_len == 0) { - output->clear(); - return true; - } - - ReserveUTF8Output(src, src_len, output); - return ConvertUnicode<char16, std::string>(src, src_len, output); -} - -std::string UTF16ToUTF8(const string16& utf16) { - std::string ret; - if (utf16.empty()) - return ret; - - // Ignore the success flag of this call, it will do the best it can for - // invalid input, which is what we want here. - UTF16ToUTF8(utf16.data(), utf16.length(), &ret); - return ret; -} - -#elif defined(WCHAR_T_IS_UTF16) -// Easy case since we can use the "wide" versions we already wrote above. - -bool UTF8ToUTF16(const char* src, size_t src_len, string16* output) { - return UTF8ToWide(src, src_len, output); -} - -string16 UTF8ToUTF16(const std::string& utf8) { - return UTF8ToWide(utf8); -} - -bool UTF16ToUTF8(const char16* src, size_t src_len, std::string* output) { - return WideToUTF8(src, src_len, output); -} - -std::string UTF16ToUTF8(const string16& utf16) { - return WideToUTF8(utf16); -} - -#endif - -// Codepage <-> Wide/UTF-16 --------------------------------------------------- - -// Convert a wstring into the specified codepage_name. If the codepage -// isn't found, return false. -bool WideToCodepage(const std::wstring& wide, - const char* codepage_name, - OnStringUtilConversionError::Type on_error, - std::string* encoded) { -#if defined(WCHAR_T_IS_UTF16) - return UTF16ToCodepage(wide, codepage_name, on_error, encoded); -#elif defined(WCHAR_T_IS_UTF32) - encoded->clear(); - - UErrorCode status = U_ZERO_ERROR; - UConverter* converter = ucnv_open(codepage_name, &status); - if (!U_SUCCESS(status)) - return false; - - int utf16_len; - // When wchar_t is wider than UChar (16 bits), transform |wide| into a - // UChar* string. Size the UChar* buffer to be large enough to hold twice - // as many UTF-16 code units (UChar's) as there are Unicode code points, - // in case each code points translates to a UTF-16 surrogate pair, - // and leave room for a NUL terminator. - std::vector<UChar> utf16(wide.length() * 2 + 1); - u_strFromWCS(&utf16[0], utf16.size(), &utf16_len, - wide.c_str(), wide.length(), &status); - DCHECK(U_SUCCESS(status)) << "failed to convert wstring to UChar*"; - - return ConvertFromUTF16(converter, &utf16[0], utf16_len, on_error, encoded); -#endif // defined(WCHAR_T_IS_UTF32) -} - -// Convert a UTF-16 string into the specified codepage_name. If the codepage -// isn't found, return false. -bool UTF16ToCodepage(const string16& utf16, - const char* codepage_name, - OnStringUtilConversionError::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); -} - -// Converts a string of the given codepage into wstring. -// If the codepage isn't found, return false. -bool CodepageToWide(const std::string& encoded, - const char* codepage_name, - OnStringUtilConversionError::Type on_error, - std::wstring* wide) { -#if defined(WCHAR_T_IS_UTF16) - return CodepageToUTF16(encoded, codepage_name, on_error, wide); -#elif defined(WCHAR_T_IS_UTF32) - wide->clear(); - - UErrorCode status = U_ZERO_ERROR; - UConverter* converter = ucnv_open(codepage_name, &status); - if (!U_SUCCESS(status)) - return false; - - // The maximum length in 4 byte unit of UTF-32 output would be - // at most the same as the number of bytes in input. In the worst - // case of GB18030 (excluding escaped-based encodings like ISO-2022-JP), - // this can be 4 times larger than actually needed. - size_t wchar_max_length = encoded.length() + 1; - - // The byte buffer and its length to pass to ucnv_toAlgorithimic. - char* byte_buffer = reinterpret_cast<char*>( - WriteInto(wide, wchar_max_length)); - int byte_buffer_length = static_cast<int>(wchar_max_length) * 4; - - SetUpErrorHandlerForToUChars(on_error, converter, &status); - int actual_size = ucnv_toAlgorithmic(utf32_platform_endian(), - converter, - byte_buffer, - byte_buffer_length, - encoded.data(), - static_cast<int>(encoded.length()), - &status); - ucnv_close(converter); - - if (!U_SUCCESS(status)) { - wide->clear(); // Make sure the output is empty on error. - return false; - } - - // actual_size is # of bytes. - wide->resize(actual_size / 4); - return true; -#endif // defined(WCHAR_T_IS_UTF32) -} - -// Converts a string of the given codepage into UTF-16. -// If the codepage isn't found, return false. -bool CodepageToUTF16(const std::string& encoded, - const char* codepage_name, - OnStringUtilConversionError::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); - int actual_size = ucnv_toUChars(converter, - WriteInto(utf16, uchar_max_length), - 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->resize(actual_size); - return true; -} - // Number formatting ----------------------------------------------------------- namespace { |