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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 17:32:43 +0000 |
commit | 6bf0a5cb5034a7e684dcc3500e841785237ce2dd (patch) | |
tree | a68f146d7fa01f0134297619fbe7e33db084e0aa /security/sandbox/chromium/base/strings/utf_string_conversion_utils.cc | |
parent | Initial commit. (diff) | |
download | thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.tar.xz thunderbird-6bf0a5cb5034a7e684dcc3500e841785237ce2dd.zip |
Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'security/sandbox/chromium/base/strings/utf_string_conversion_utils.cc')
-rw-r--r-- | security/sandbox/chromium/base/strings/utf_string_conversion_utils.cc | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/security/sandbox/chromium/base/strings/utf_string_conversion_utils.cc b/security/sandbox/chromium/base/strings/utf_string_conversion_utils.cc new file mode 100644 index 0000000000..f7682c1be9 --- /dev/null +++ b/security/sandbox/chromium/base/strings/utf_string_conversion_utils.cc @@ -0,0 +1,155 @@ +// 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/strings/utf_string_conversion_utils.h" + +#include "base/third_party/icu/icu_utf.h" +#include "build/build_config.h" + +namespace base { + +// ReadUnicodeCharacter -------------------------------------------------------- + +bool ReadUnicodeCharacter(const char* src, + int32_t src_len, + int32_t* char_index, + uint32_t* 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_t code_point; + CBU8_NEXT(src, *char_index, src_len, code_point); + *code_point_out = static_cast<uint32_t>(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); +} + +bool ReadUnicodeCharacter(const char16* src, + int32_t src_len, + int32_t* char_index, + uint32_t* code_point) { + if (CBU16_IS_SURROGATE(src[*char_index])) { + if (!CBU16_IS_SURROGATE_LEAD(src[*char_index]) || + *char_index + 1 >= src_len || + !CBU16_IS_TRAIL(src[*char_index + 1])) { + // Invalid surrogate pair. + return false; + } + + // Valid surrogate pair. + *code_point = CBU16_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) +bool ReadUnicodeCharacter(const wchar_t* src, + int32_t src_len, + int32_t* char_index, + uint32_t* 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 ------------------------------------------------------- + +size_t WriteUnicodeCharacter(uint32_t code_point, std::string* output) { + if (code_point <= 0x7f) { + // Fast path the common case of one byte. + output->push_back(static_cast<char>(code_point)); + return 1; + } + + + // CBU8_APPEND_UNSAFE can append up to 4 bytes. + size_t char_offset = output->length(); + size_t original_char_offset = char_offset; + output->resize(char_offset + CBU8_MAX_LENGTH); + + CBU8_APPEND_UNSAFE(&(*output)[0], char_offset, code_point); + + // CBU8_APPEND_UNSAFE will advance our pointer past the inserted character, so + // it will represent the new length of the string. + output->resize(char_offset); + return char_offset - original_char_offset; +} + +size_t WriteUnicodeCharacter(uint32_t code_point, string16* output) { + if (CBU16_LENGTH(code_point) == 1) { + // Thie code point is in the Basic Multilingual Plane (BMP). + output->push_back(static_cast<char16>(code_point)); + return 1; + } + // Non-BMP characters use a double-character encoding. + size_t char_offset = output->length(); + output->resize(char_offset + CBU16_MAX_LENGTH); + CBU16_APPEND_UNSAFE(&(*output)[0], char_offset, code_point); + return CBU16_MAX_LENGTH; +} + +// Generalized Unicode converter ----------------------------------------------- + +template<typename CHAR> +void PrepareForUTF8Output(const CHAR* src, + size_t src_len, + std::string* output) { + output->clear(); + if (src_len == 0) + return; + 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); + } +} + +// Instantiate versions we know callers will need. +#if !defined(OS_WIN) +// wchar_t and char16 are the same thing on Windows. +template void PrepareForUTF8Output(const wchar_t*, size_t, std::string*); +#endif +template void PrepareForUTF8Output(const char16*, size_t, std::string*); + +template<typename STRING> +void PrepareForUTF16Or32Output(const char* src, + size_t src_len, + STRING* output) { + output->clear(); + if (src_len == 0) + return; + 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); + } +} + +// Instantiate versions we know callers will need. +#if !defined(OS_WIN) +// std::wstring and string16 are the same thing on Windows. +template void PrepareForUTF16Or32Output(const char*, size_t, std::wstring*); +#endif +template void PrepareForUTF16Or32Output(const char*, size_t, string16*); + +} // namespace base |