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-rw-r--r--security/sandbox/chromium/base/strings/utf_string_conversion_utils.cc155
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