blob: 97b027a6f747b2cd979b5c3b6ad2df325bec4e02 [file] [log] [blame]
// 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/strings/sys_string_conversions.h"
#include <stddef.h>
#include <wchar.h>
#include "base/strings/string_piece.h"
#include "base/strings/utf_string_conversions.h"
#include "build_config.h"
namespace base {
std::string SysWideToUTF8(const std::wstring& wide) {
// In theory this should be using the system-provided conversion rather
// than our ICU, but this will do for now.
return WideToUTF8(wide);
}
std::wstring SysUTF8ToWide(StringPiece utf8) {
// In theory this should be using the system-provided conversion rather
// than our ICU, but this will do for now.
std::wstring out;
UTF8ToWide(utf8.data(), utf8.size(), &out);
return out;
}
#if defined(SYSTEM_NATIVE_UTF8) || defined(OS_ANDROID)
// TODO(port): Consider reverting the OS_ANDROID when we have wcrtomb()
// support and a better understanding of what calls these routines.
std::string SysWideToNativeMB(const std::wstring& wide) {
return WideToUTF8(wide);
}
std::wstring SysNativeMBToWide(StringPiece native_mb) {
return SysUTF8ToWide(native_mb);
}
#else
std::string SysWideToNativeMB(const std::wstring& wide) {
mbstate_t ps;
// Calculate the number of multi-byte characters. We walk through the string
// without writing the output, counting the number of multi-byte characters.
size_t num_out_chars = 0;
memset(&ps, 0, sizeof(ps));
for (size_t i = 0; i < wide.size(); ++i) {
const wchar_t src = wide[i];
// Use a temp buffer since calling wcrtomb with an output of NULL does not
// calculate the output length.
char buf[16];
// Skip NULLs to avoid wcrtomb's special handling of them.
size_t res = src ? wcrtomb(buf, src, &ps) : 0;
switch (res) {
// Handle any errors and return an empty string.
case static_cast<size_t>(-1):
return std::string();
break;
case 0:
// We hit an embedded null byte, keep going.
++num_out_chars;
break;
default:
num_out_chars += res;
break;
}
}
if (num_out_chars == 0)
return std::string();
std::string out;
out.resize(num_out_chars);
// We walk the input string again, with |i| tracking the index of the
// wide input, and |j| tracking the multi-byte output.
memset(&ps, 0, sizeof(ps));
for (size_t i = 0, j = 0; i < wide.size(); ++i) {
const wchar_t src = wide[i];
// We don't want wcrtomb to do its funkiness for embedded NULLs.
size_t res = src ? wcrtomb(&out[j], src, &ps) : 0;
switch (res) {
// Handle any errors and return an empty string.
case static_cast<size_t>(-1):
return std::string();
break;
case 0:
// We hit an embedded null byte, keep going.
++j; // Output is already zeroed.
break;
default:
j += res;
break;
}
}
return out;
}
std::wstring SysNativeMBToWide(StringPiece native_mb) {
mbstate_t ps;
// Calculate the number of wide characters. We walk through the string
// without writing the output, counting the number of wide characters.
size_t num_out_chars = 0;
memset(&ps, 0, sizeof(ps));
for (size_t i = 0; i < native_mb.size(); ) {
const char* src = native_mb.data() + i;
size_t res = mbrtowc(nullptr, src, native_mb.size() - i, &ps);
switch (res) {
// Handle any errors and return an empty string.
case static_cast<size_t>(-2):
case static_cast<size_t>(-1):
return std::wstring();
break;
case 0:
// We hit an embedded null byte, keep going.
i += 1;
FALLTHROUGH;
default:
i += res;
++num_out_chars;
break;
}
}
if (num_out_chars == 0)
return std::wstring();
std::wstring out;
out.resize(num_out_chars);
memset(&ps, 0, sizeof(ps)); // Clear the shift state.
// We walk the input string again, with |i| tracking the index of the
// multi-byte input, and |j| tracking the wide output.
for (size_t i = 0, j = 0; i < native_mb.size(); ++j) {
const char* src = native_mb.data() + i;
wchar_t* dst = &out[j];
size_t res = mbrtowc(dst, src, native_mb.size() - i, &ps);
switch (res) {
// Handle any errors and return an empty string.
case static_cast<size_t>(-2):
case static_cast<size_t>(-1):
return std::wstring();
break;
case 0:
i += 1; // Skip null byte.
break;
default:
i += res;
break;
}
}
return out;
}
#endif // defined(SYSTEM_NATIVE_UTF8) || defined(OS_ANDROID)
} // namespace base