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/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef ART_RUNTIME_UTF_H_
#define ART_RUNTIME_UTF_H_
#include "base/macros.h"
#include "base/mutex.h"
#include <stddef.h>
#include <stdint.h>
/*
* All UTF-8 in art is actually modified UTF-8. Mostly, this distinction
* doesn't matter.
*
* See http://en.wikipedia.org/wiki/UTF-8#Modified_UTF-8 for the details.
*/
namespace art {
namespace mirror {
template<class T> class PrimitiveArray;
typedef PrimitiveArray<uint16_t> CharArray;
} // namespace mirror
/*
* Returns the number of UTF-16 characters in the given modified UTF-8 string.
*/
size_t CountModifiedUtf8Chars(const char* utf8);
size_t CountModifiedUtf8Chars(const char* utf8, size_t byte_count);
/*
* Returns the number of modified UTF-8 bytes needed to represent the given
* UTF-16 string.
*/
size_t CountUtf8Bytes(const uint16_t* chars, size_t char_count);
/*
* Convert from Modified UTF-8 to UTF-16.
*/
void ConvertModifiedUtf8ToUtf16(uint16_t* utf16_out, const char* utf8_in);
void ConvertModifiedUtf8ToUtf16(uint16_t* utf16_out, size_t out_chars,
const char* utf8_in, size_t in_bytes);
/*
* Compare two modified UTF-8 strings as UTF-16 code point values in a non-locale sensitive manner
*/
ALWAYS_INLINE int CompareModifiedUtf8ToModifiedUtf8AsUtf16CodePointValues(const char* utf8_1,
const char* utf8_2);
/*
* Compare a null-terminated modified UTF-8 string with a UTF-16 string (not null-terminated)
* as code point values in a non-locale sensitive manner.
*/
int CompareModifiedUtf8ToUtf16AsCodePointValues(const char* utf8, const uint16_t* utf16,
size_t utf16_length);
/*
* Convert from UTF-16 to Modified UTF-8. Note that the output is _not_
* NUL-terminated. You probably need to call CountUtf8Bytes before calling
* this anyway, so if you want a NUL-terminated string, you know where to
* put the NUL byte.
*/
void ConvertUtf16ToModifiedUtf8(char* utf8_out, size_t byte_count,
const uint16_t* utf16_in, size_t char_count);
/*
* The java.lang.String hashCode() algorithm.
*/
int32_t ComputeUtf16Hash(mirror::CharArray* chars, int32_t offset, size_t char_count)
SHARED_REQUIRES(Locks::mutator_lock_);
template<typename MemoryType>
int32_t ComputeUtf16Hash(const MemoryType* chars, size_t char_count) {
uint32_t hash = 0;
while (char_count--) {
hash = hash * 31 + *chars++;
}
return static_cast<int32_t>(hash);
}
int32_t ComputeUtf16HashFromModifiedUtf8(const char* utf8, size_t utf16_length);
// Compute a hash code of a modified UTF-8 string. Not the standard java hash since it returns a
// uint32_t and hashes individual chars instead of codepoint words.
uint32_t ComputeModifiedUtf8Hash(const char* chars);
/*
* Retrieve the next UTF-16 character or surrogate pair from a UTF-8 string.
* single byte, 2-byte and 3-byte UTF-8 sequences result in a single UTF-16
* character (possibly one half of a surrogate) whereas 4-byte UTF-8 sequences
* result in a surrogate pair. Use GetLeadingUtf16Char and GetTrailingUtf16Char
* to process the return value of this function.
*
* Advances "*utf8_data_in" to the start of the next character.
*
* WARNING: If a string is corrupted by dropping a '\0' in the middle
* of a multi byte sequence, you can end up overrunning the buffer with
* reads (and possibly with the writes if the length was computed and
* cached before the damage). For performance reasons, this function
* assumes that the string being parsed is known to be valid (e.g., by
* already being verified). Most strings we process here are coming
* out of dex files or other internal translations, so the only real
* risk comes from the JNI NewStringUTF call.
*/
uint32_t GetUtf16FromUtf8(const char** utf8_data_in);
/**
* Gets the leading UTF-16 character from a surrogate pair, or the sole
* UTF-16 character from the return value of GetUtf16FromUtf8.
*/
ALWAYS_INLINE uint16_t GetLeadingUtf16Char(uint32_t maybe_pair);
/**
* Gets the trailing UTF-16 character from a surrogate pair, or 0 otherwise
* from the return value of GetUtf16FromUtf8.
*/
ALWAYS_INLINE uint16_t GetTrailingUtf16Char(uint32_t maybe_pair);
} // namespace art
#endif // ART_RUNTIME_UTF_H_