chromium/third_party/icu/source/i18n/csr2022.cpp

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
 **********************************************************************
 *   Copyright (C) 2005-2016, International Business Machines
 *   Corporation and others.  All Rights Reserved.
 **********************************************************************
 */

#include "unicode/utypes.h"

#if !UCONFIG_NO_CONVERSION

#include "cmemory.h"
#include "cstring.h"

#include "csr2022.h"
#include "csmatch.h"

U_NAMESPACE_BEGIN

/**
 * Matching function shared among the 2022 detectors JP, CN and KR
 * Counts up the number of legal and unrecognized escape sequences in
 * the sample of text, and computes a score based on the total number &
 * the proportion that fit the encoding.
 * 
 * 
 * @param text the byte buffer containing text to analyse
 * @param textLen  the size of the text in the byte.
 * @param escapeSequences the byte escape sequences to test for.
 * @return match quality, in the range of 0-100.
 */
int32_t CharsetRecog_2022::match_2022(const uint8_t *text, int32_t textLen, const uint8_t escapeSequences[][5], int32_t escapeSequences_length) const
{ … }


static const uint8_t escapeSequences_2022JP[][5] = …;

#if !UCONFIG_ONLY_HTML_CONVERSION
static const uint8_t escapeSequences_2022KR[][5] = {
    {0x1b, 0x24, 0x29, 0x43, 0x00}   
};

static const uint8_t escapeSequences_2022CN[][5] = {
    {0x1b, 0x24, 0x29, 0x41, 0x00},   // GB 2312-80
    {0x1b, 0x24, 0x29, 0x47, 0x00},   // CNS 11643-1992 Plane 1
    {0x1b, 0x24, 0x2A, 0x48, 0x00},   // CNS 11643-1992 Plane 2
    {0x1b, 0x24, 0x29, 0x45, 0x00},   // ISO-IR-165
    {0x1b, 0x24, 0x2B, 0x49, 0x00},   // CNS 11643-1992 Plane 3
    {0x1b, 0x24, 0x2B, 0x4A, 0x00},   // CNS 11643-1992 Plane 4
    {0x1b, 0x24, 0x2B, 0x4B, 0x00},   // CNS 11643-1992 Plane 5
    {0x1b, 0x24, 0x2B, 0x4C, 0x00},   // CNS 11643-1992 Plane 6
    {0x1b, 0x24, 0x2B, 0x4D, 0x00},   // CNS 11643-1992 Plane 7
    {0x1b, 0x4e, 0x00, 0x00, 0x00},   // SS2
    {0x1b, 0x4f, 0x00, 0x00, 0x00},   // SS3
};
#endif

CharsetRecog_2022JP::~CharsetRecog_2022JP() { … }

const char *CharsetRecog_2022JP::getName() const { … }

UBool CharsetRecog_2022JP::match(InputText *textIn, CharsetMatch *results) const { … }

#if !UCONFIG_ONLY_HTML_CONVERSION
CharsetRecog_2022KR::~CharsetRecog_2022KR() {}

const char *CharsetRecog_2022KR::getName() const {
    return "ISO-2022-KR";
}

UBool CharsetRecog_2022KR::match(InputText *textIn, CharsetMatch *results) const {
    int32_t confidence = match_2022(textIn->fInputBytes, 
                                    textIn->fInputLen, 
                                    escapeSequences_2022KR, 
                                    UPRV_LENGTHOF(escapeSequences_2022KR));
    results->set(textIn, this, confidence);
    return (confidence > 0);
}

CharsetRecog_2022CN::~CharsetRecog_2022CN() {}

const char *CharsetRecog_2022CN::getName() const {
    return "ISO-2022-CN";
}

UBool CharsetRecog_2022CN::match(InputText *textIn, CharsetMatch *results) const {
    int32_t confidence = match_2022(textIn->fInputBytes,
                                    textIn->fInputLen,
                                    escapeSequences_2022CN,
                                    UPRV_LENGTHOF(escapeSequences_2022CN));
    results->set(textIn, this, confidence);
    return (confidence > 0);
}
#endif

CharsetRecog_2022::~CharsetRecog_2022() { … }

U_NAMESPACE_END
#endif