security/sandbox/chromium/base/strings/utf_string_conversion_utils.h

Tue, 06 Jan 2015 21:39:09 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Tue, 06 Jan 2015 21:39:09 +0100
branch
TOR_BUG_9701
changeset 8
97036ab72558
permissions
-rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

michael@0 1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
michael@0 2 // Use of this source code is governed by a BSD-style license that can be
michael@0 3 // found in the LICENSE file.
michael@0 4
michael@0 5 #ifndef BASE_STRINGS_UTF_STRING_CONVERSION_UTILS_H_
michael@0 6 #define BASE_STRINGS_UTF_STRING_CONVERSION_UTILS_H_
michael@0 7
michael@0 8 // This should only be used by the various UTF string conversion files.
michael@0 9
michael@0 10 #include "base/base_export.h"
michael@0 11 #include "base/strings/string16.h"
michael@0 12
michael@0 13 namespace base {
michael@0 14
michael@0 15 inline bool IsValidCodepoint(uint32 code_point) {
michael@0 16 // Excludes the surrogate code points ([0xD800, 0xDFFF]) and
michael@0 17 // codepoints larger than 0x10FFFF (the highest codepoint allowed).
michael@0 18 // Non-characters and unassigned codepoints are allowed.
michael@0 19 return code_point < 0xD800u ||
michael@0 20 (code_point >= 0xE000u && code_point <= 0x10FFFFu);
michael@0 21 }
michael@0 22
michael@0 23 inline bool IsValidCharacter(uint32 code_point) {
michael@0 24 // Excludes non-characters (U+FDD0..U+FDEF, and all codepoints ending in
michael@0 25 // 0xFFFE or 0xFFFF) from the set of valid code points.
michael@0 26 return code_point < 0xD800u || (code_point >= 0xE000u &&
michael@0 27 code_point < 0xFDD0u) || (code_point > 0xFDEFu &&
michael@0 28 code_point <= 0x10FFFFu && (code_point & 0xFFFEu) != 0xFFFEu);
michael@0 29 }
michael@0 30
michael@0 31 // ReadUnicodeCharacter --------------------------------------------------------
michael@0 32
michael@0 33 // Reads a UTF-8 stream, placing the next code point into the given output
michael@0 34 // |*code_point|. |src| represents the entire string to read, and |*char_index|
michael@0 35 // is the character offset within the string to start reading at. |*char_index|
michael@0 36 // will be updated to index the last character read, such that incrementing it
michael@0 37 // (as in a for loop) will take the reader to the next character.
michael@0 38 //
michael@0 39 // Returns true on success. On false, |*code_point| will be invalid.
michael@0 40 BASE_EXPORT bool ReadUnicodeCharacter(const char* src,
michael@0 41 int32 src_len,
michael@0 42 int32* char_index,
michael@0 43 uint32* code_point_out);
michael@0 44
michael@0 45 // Reads a UTF-16 character. The usage is the same as the 8-bit version above.
michael@0 46 BASE_EXPORT bool ReadUnicodeCharacter(const char16* src,
michael@0 47 int32 src_len,
michael@0 48 int32* char_index,
michael@0 49 uint32* code_point);
michael@0 50
michael@0 51 #if defined(WCHAR_T_IS_UTF32)
michael@0 52 // Reads UTF-32 character. The usage is the same as the 8-bit version above.
michael@0 53 BASE_EXPORT bool ReadUnicodeCharacter(const wchar_t* src,
michael@0 54 int32 src_len,
michael@0 55 int32* char_index,
michael@0 56 uint32* code_point);
michael@0 57 #endif // defined(WCHAR_T_IS_UTF32)
michael@0 58
michael@0 59 // WriteUnicodeCharacter -------------------------------------------------------
michael@0 60
michael@0 61 // Appends a UTF-8 character to the given 8-bit string. Returns the number of
michael@0 62 // bytes written.
michael@0 63 // TODO(brettw) Bug 79631: This function should not be exposed.
michael@0 64 BASE_EXPORT size_t WriteUnicodeCharacter(uint32 code_point,
michael@0 65 std::string* output);
michael@0 66
michael@0 67 // Appends the given code point as a UTF-16 character to the given 16-bit
michael@0 68 // string. Returns the number of 16-bit values written.
michael@0 69 BASE_EXPORT size_t WriteUnicodeCharacter(uint32 code_point, string16* output);
michael@0 70
michael@0 71 #if defined(WCHAR_T_IS_UTF32)
michael@0 72 // Appends the given UTF-32 character to the given 32-bit string. Returns the
michael@0 73 // number of 32-bit values written.
michael@0 74 inline size_t WriteUnicodeCharacter(uint32 code_point, std::wstring* output) {
michael@0 75 // This is the easy case, just append the character.
michael@0 76 output->push_back(code_point);
michael@0 77 return 1;
michael@0 78 }
michael@0 79 #endif // defined(WCHAR_T_IS_UTF32)
michael@0 80
michael@0 81 // Generalized Unicode converter -----------------------------------------------
michael@0 82
michael@0 83 // Guesses the length of the output in UTF-8 in bytes, clears that output
michael@0 84 // string, and reserves that amount of space. We assume that the input
michael@0 85 // character types are unsigned, which will be true for UTF-16 and -32 on our
michael@0 86 // systems.
michael@0 87 template<typename CHAR>
michael@0 88 void PrepareForUTF8Output(const CHAR* src, size_t src_len, std::string* output);
michael@0 89
michael@0 90 // Prepares an output buffer (containing either UTF-16 or -32 data) given some
michael@0 91 // UTF-8 input that will be converted to it. See PrepareForUTF8Output().
michael@0 92 template<typename STRING>
michael@0 93 void PrepareForUTF16Or32Output(const char* src, size_t src_len, STRING* output);
michael@0 94
michael@0 95 } // namespace base
michael@0 96
michael@0 97 #endif // BASE_STRINGS_UTF_STRING_CONVERSION_UTILS_H_

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