Utf8Utils for dicttoolkit.

        makedict_executor.cpp) \

    $(addprefix offdevice_intermediate_dict/, \

        offdevice_intermediate_dict.cpp) \

    utils/command_utils.cpp

    $(addprefix utils/, \

        command_utils.cpp \

        utf8_utils.cpp)

LATIN_IME_DICT_TOOLKIT_TEST_FILES := \

    dict_toolkit_defines_test.cpp \

    $(addprefix offdevice_intermediate_dict/, \

        offdevice_intermediate_dict_test.cpp) \

    $(addprefix utils/, \

        command_utils_test.cpp)

        command_utils_test.cpp \

        utf8_utils_test.cpp)

/*

 * Copyright (C) 2014 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.

 */

#include "utils/utf8_utils.h"

#include "utils/char_utils.h"

namespace latinime {

namespace dicttoolkit {

const size_t Utf8Utils::MAX_SEQUENCE_SIZE_FOR_A_CODE_POINT = 4;

const uint8_t Utf8Utils::FIRST_BYTE_MARKER_MASKS[] = {0, 0x80, 0xE0, 0xF0, 0xF8};

const uint8_t Utf8Utils::FIRST_BYTE_MARKERS[] = {0, 0x00, 0xC0, 0xE0, 0xF0};

const uint8_t Utf8Utils::FIRST_BYTE_CODE_POINT_BITS_MASKS[] = {0, 0x7F, 0x1F, 0x0F, 0x03};

const int Utf8Utils::MAX_ENCODED_CODE_POINT_VALUES[] = {-1, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};

const uint8_t Utf8Utils::TRAILING_BYTE_CODE_POINT_BITS_MASK = 0x3F;

const uint8_t Utf8Utils::TRAILING_BYTE_MARKER = 0x80;

const size_t Utf8Utils::CODE_POINT_BIT_COUNT_IN_TRAILING_BYTE = 6;

/* static */ std::vector<int> Utf8Utils::getCodePoints(const std::string &utf8Str) {

    std::vector<int> codePoints;

    int remainingByteCountForCurrentCodePoint = 0;

    int currentCodePointSequenceSize = 0;

    int codePoint = 0;

    for (const char c : utf8Str) {

        if (remainingByteCountForCurrentCodePoint == 0) {

            currentCodePointSequenceSize = getSequenceSizeByCheckingFirstByte(c);

            if (currentCodePointSequenceSize <= 0) {

                AKLOGE("%x is an invalid utf8 first byte value.", c);

                return std::vector<int>();

            }

            remainingByteCountForCurrentCodePoint = currentCodePointSequenceSize;

            codePoint = maskFirstByte(c, remainingByteCountForCurrentCodePoint);

        } else {

            codePoint <<= CODE_POINT_BIT_COUNT_IN_TRAILING_BYTE;

            codePoint += maskTrailingByte(c);

        }

        remainingByteCountForCurrentCodePoint--;

        if (remainingByteCountForCurrentCodePoint == 0) {

            if (codePoint <= MAX_ENCODED_CODE_POINT_VALUES[currentCodePointSequenceSize - 1]) {

                AKLOGE("%d bytes encode for codePoint(%x) is a redundant UTF-8 sequence.",

                        currentCodePointSequenceSize,  codePoint);

                return std::vector<int>();

            }

            codePoints.push_back(codePoint);

        }

    }

    return codePoints;

}

/* static */ int Utf8Utils::getSequenceSizeByCheckingFirstByte(const uint8_t firstByte) {

    for (size_t i = 1; i <= MAX_SEQUENCE_SIZE_FOR_A_CODE_POINT; ++i) {

        if ((firstByte & FIRST_BYTE_MARKER_MASKS[i]) == FIRST_BYTE_MARKERS[i]) {

            return i;

        }

    }

    // Not a valid utf8 char first byte.

    return -1;

}

/* static */ AK_FORCE_INLINE int Utf8Utils::maskFirstByte(const uint8_t firstByte,

        const int sequenceSize) {

    return firstByte & FIRST_BYTE_CODE_POINT_BITS_MASKS[sequenceSize];

}

/* static */ AK_FORCE_INLINE int Utf8Utils::maskTrailingByte(const uint8_t secondOrLaterByte) {

    return secondOrLaterByte & TRAILING_BYTE_CODE_POINT_BITS_MASK;

}

/* static */ std::string Utf8Utils::getUtf8String(const CodePointArrayView codePoints) {

    std::string utf8String;

    for (const int codePoint : codePoints) {

        const int sequenceSize = getSequenceSizeToEncodeCodePoint(codePoint);

        if (sequenceSize <= 0) {

            AKLOGE("Cannot encode code point (%d).", codePoint);

            return std::string();

        }

        const int trailingByteCount = sequenceSize - 1;

        // Output first byte.

        const int value = codePoint >> (trailingByteCount * CODE_POINT_BIT_COUNT_IN_TRAILING_BYTE);

        utf8String.push_back(static_cast<char>(value | FIRST_BYTE_MARKERS[sequenceSize]));

        // Output second and later bytes.

        for (int i = 1; i < sequenceSize; ++i) {

            const int shiftAmount = (trailingByteCount - i) * CODE_POINT_BIT_COUNT_IN_TRAILING_BYTE;

            const int value = (codePoint >> shiftAmount) & TRAILING_BYTE_CODE_POINT_BITS_MASK;

            utf8String.push_back(static_cast<char>(value | TRAILING_BYTE_MARKER));

        }

    }

    return utf8String;

}

/* static */ int Utf8Utils::getSequenceSizeToEncodeCodePoint(const int codePoint) {

    if (codePoint < 0) {

        return -1;

    }

    for (size_t i = 1; i <= MAX_SEQUENCE_SIZE_FOR_A_CODE_POINT; ++i) {

        if (codePoint <= MAX_ENCODED_CODE_POINT_VALUES[i]) {

            return i;

        }

    }

    return -1;

}

} // namespace dicttoolkit

} // namespace latinime

/*

 * Copyright (C) 2014 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 LATINIME_DICT_TOOLKIT_UTF8_UTILS_H

#define LATINIME_DICT_TOOLKIT_UTF8_UTILS_H

#include <cstdint>

#include <string>

#include <vector>

#include "dict_toolkit_defines.h"

#include "utils/int_array_view.h"

namespace latinime {

namespace dicttoolkit {

class Utf8Utils {

public:

    static std::vector<int> getCodePoints(const std::string &utf8Str);

    static std::string getUtf8String(const CodePointArrayView codePoints);

private:

    DISALLOW_IMPLICIT_CONSTRUCTORS(Utf8Utils);

    // Values indexed by sequence size.

    static const size_t MAX_SEQUENCE_SIZE_FOR_A_CODE_POINT;

    static const uint8_t FIRST_BYTE_MARKER_MASKS[];

    static const uint8_t FIRST_BYTE_MARKERS[];

    static const uint8_t FIRST_BYTE_CODE_POINT_BITS_MASKS[];

    static const int MAX_ENCODED_CODE_POINT_VALUES[];

    static const uint8_t TRAILING_BYTE_CODE_POINT_BITS_MASK;

    static const uint8_t TRAILING_BYTE_MARKER;

    static const size_t CODE_POINT_BIT_COUNT_IN_TRAILING_BYTE;

    static int getSequenceSizeByCheckingFirstByte(const uint8_t firstByte);

    static int maskFirstByte(const uint8_t firstByte, const int encodeSize);

    static int maskTrailingByte(const uint8_t secondOrLaterByte);

    static int getSequenceSizeToEncodeCodePoint(const int codePoint);

};

} // namespace dicttoolkit

} // namespace latinime

#endif // LATINIME_DICT_TOOLKIT_UTF8_UTILS_H

/*

 * Copyright (C) 2014 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.

 */

#include "utils/utf8_utils.h"

#include <gtest/gtest.h>

#include <vector>

#include "utils/int_array_view.h"

namespace latinime {

namespace dicttoolkit {

namespace {

TEST(Utf8UtilsTests, TestGetCodePoints) {

    {

        const std::vector<int> codePoints = Utf8Utils::getCodePoints("");

        EXPECT_EQ(0u, codePoints.size());

    }

    {

        const std::vector<int> codePoints = Utf8Utils::getCodePoints("test");

        EXPECT_EQ(4u, codePoints.size());

        EXPECT_EQ('t', codePoints[0]);

        EXPECT_EQ('e', codePoints[1]);

        EXPECT_EQ('s', codePoints[2]);

        EXPECT_EQ('t', codePoints[3]);

    }

    {

        const std::vector<int> codePoints = Utf8Utils::getCodePoints(u8"\u3042a\u03C2\u0410");

        EXPECT_EQ(4u, codePoints.size());

        EXPECT_EQ(0x3042, codePoints[0]); // HIRAGANA LETTER A

        EXPECT_EQ('a', codePoints[1]);

        EXPECT_EQ(0x03C2, codePoints[2]); // CYRILLIC CAPITAL LETTER A

        EXPECT_EQ(0x0410, codePoints[3]); // GREEK SMALL LETTER FINAL SIGMA

    }

    {

        const std::vector<int> codePoints = Utf8Utils::getCodePoints(u8"\U0001F36A?\U0001F752");

        EXPECT_EQ(3u, codePoints.size());

        EXPECT_EQ(0x1F36A, codePoints[0]); // COOKIE

        EXPECT_EQ('?', codePoints[1]);

        EXPECT_EQ(0x1F752, codePoints[2]); // ALCHEMICAL SYMBOL FOR STARRED TRIDENT

    }

    // Redundant UTF-8 sequences must be rejected.

    EXPECT_TRUE(Utf8Utils::getCodePoints("\xC0\xAF").empty());

    EXPECT_TRUE(Utf8Utils::getCodePoints("\xE0\x80\xAF").empty());

    EXPECT_TRUE(Utf8Utils::getCodePoints("\xF0\x80\x80\xAF").empty());

}

TEST(Utf8UtilsTests, TestGetUtf8String) {

    {

        const std::vector<int> codePoints = {'t', 'e', 's', 't'};

        EXPECT_EQ("test", Utf8Utils::getUtf8String(CodePointArrayView(codePoints)));

    }

    {

        const std::vector<int> codePoints = {

                0x00E0 /* LATIN SMALL LETTER A WITH GRAVE */,

                0x03C2 /* GREEK SMALL LETTER FINAL SIGMA */,

                0x0430 /* CYRILLIC SMALL LETTER A */,

                0x3042 /* HIRAGANA LETTER A */,

                0x1F36A /* COOKIE */,

                0x1F752 /* ALCHEMICAL SYMBOL FOR STARRED TRIDENT */

        };

        EXPECT_EQ(u8"\u00E0\u03C2\u0430\u3042\U0001F36A\U0001F752",

                Utf8Utils::getUtf8String(CodePointArrayView(codePoints)));

    }

}

} // namespace

} // namespace dicttoolkit

} // namespace latinime