diff options
Diffstat (limited to 'intl/icu/source/i18n/csrmbcs.cpp')
-rw-r--r-- | intl/icu/source/i18n/csrmbcs.cpp | 527 |
1 files changed, 527 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/csrmbcs.cpp b/intl/icu/source/i18n/csrmbcs.cpp new file mode 100644 index 0000000000..ec346b5fb3 --- /dev/null +++ b/intl/icu/source/i18n/csrmbcs.cpp @@ -0,0 +1,527 @@ +// © 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 "csmatch.h" +#include "csrmbcs.h" + +#include <math.h> + +U_NAMESPACE_BEGIN + +#define min(x,y) (((x)<(y))?(x):(y)) + +static const uint16_t commonChars_sjis [] = { +// TODO: This set of data comes from the character frequency- +// of-occurrence analysis tool. The data needs to be moved +// into a resource and loaded from there. +0x8140, 0x8141, 0x8142, 0x8145, 0x815b, 0x8169, 0x816a, 0x8175, 0x8176, 0x82a0, +0x82a2, 0x82a4, 0x82a9, 0x82aa, 0x82ab, 0x82ad, 0x82af, 0x82b1, 0x82b3, 0x82b5, +0x82b7, 0x82bd, 0x82be, 0x82c1, 0x82c4, 0x82c5, 0x82c6, 0x82c8, 0x82c9, 0x82cc, +0x82cd, 0x82dc, 0x82e0, 0x82e7, 0x82e8, 0x82e9, 0x82ea, 0x82f0, 0x82f1, 0x8341, +0x8343, 0x834e, 0x834f, 0x8358, 0x835e, 0x8362, 0x8367, 0x8375, 0x8376, 0x8389, +0x838a, 0x838b, 0x838d, 0x8393, 0x8e96, 0x93fa, 0x95aa}; + +static const uint16_t commonChars_euc_jp[] = { +// TODO: This set of data comes from the character frequency- +// of-occurrence analysis tool. The data needs to be moved +// into a resource and loaded from there. +0xa1a1, 0xa1a2, 0xa1a3, 0xa1a6, 0xa1bc, 0xa1ca, 0xa1cb, 0xa1d6, 0xa1d7, 0xa4a2, +0xa4a4, 0xa4a6, 0xa4a8, 0xa4aa, 0xa4ab, 0xa4ac, 0xa4ad, 0xa4af, 0xa4b1, 0xa4b3, +0xa4b5, 0xa4b7, 0xa4b9, 0xa4bb, 0xa4bd, 0xa4bf, 0xa4c0, 0xa4c1, 0xa4c3, 0xa4c4, +0xa4c6, 0xa4c7, 0xa4c8, 0xa4c9, 0xa4ca, 0xa4cb, 0xa4ce, 0xa4cf, 0xa4d0, 0xa4de, +0xa4df, 0xa4e1, 0xa4e2, 0xa4e4, 0xa4e8, 0xa4e9, 0xa4ea, 0xa4eb, 0xa4ec, 0xa4ef, +0xa4f2, 0xa4f3, 0xa5a2, 0xa5a3, 0xa5a4, 0xa5a6, 0xa5a7, 0xa5aa, 0xa5ad, 0xa5af, +0xa5b0, 0xa5b3, 0xa5b5, 0xa5b7, 0xa5b8, 0xa5b9, 0xa5bf, 0xa5c3, 0xa5c6, 0xa5c7, +0xa5c8, 0xa5c9, 0xa5cb, 0xa5d0, 0xa5d5, 0xa5d6, 0xa5d7, 0xa5de, 0xa5e0, 0xa5e1, +0xa5e5, 0xa5e9, 0xa5ea, 0xa5eb, 0xa5ec, 0xa5ed, 0xa5f3, 0xb8a9, 0xb9d4, 0xbaee, +0xbbc8, 0xbef0, 0xbfb7, 0xc4ea, 0xc6fc, 0xc7bd, 0xcab8, 0xcaf3, 0xcbdc, 0xcdd1}; + +static const uint16_t commonChars_euc_kr[] = { +// TODO: This set of data comes from the character frequency- +// of-occurrence analysis tool. The data needs to be moved +// into a resource and loaded from there. +0xb0a1, 0xb0b3, 0xb0c5, 0xb0cd, 0xb0d4, 0xb0e6, 0xb0ed, 0xb0f8, 0xb0fa, 0xb0fc, +0xb1b8, 0xb1b9, 0xb1c7, 0xb1d7, 0xb1e2, 0xb3aa, 0xb3bb, 0xb4c2, 0xb4cf, 0xb4d9, +0xb4eb, 0xb5a5, 0xb5b5, 0xb5bf, 0xb5c7, 0xb5e9, 0xb6f3, 0xb7af, 0xb7c2, 0xb7ce, +0xb8a6, 0xb8ae, 0xb8b6, 0xb8b8, 0xb8bb, 0xb8e9, 0xb9ab, 0xb9ae, 0xb9cc, 0xb9ce, +0xb9fd, 0xbab8, 0xbace, 0xbad0, 0xbaf1, 0xbbe7, 0xbbf3, 0xbbfd, 0xbcad, 0xbcba, +0xbcd2, 0xbcf6, 0xbdba, 0xbdc0, 0xbdc3, 0xbdc5, 0xbec6, 0xbec8, 0xbedf, 0xbeee, +0xbef8, 0xbefa, 0xbfa1, 0xbfa9, 0xbfc0, 0xbfe4, 0xbfeb, 0xbfec, 0xbff8, 0xc0a7, +0xc0af, 0xc0b8, 0xc0ba, 0xc0bb, 0xc0bd, 0xc0c7, 0xc0cc, 0xc0ce, 0xc0cf, 0xc0d6, +0xc0da, 0xc0e5, 0xc0fb, 0xc0fc, 0xc1a4, 0xc1a6, 0xc1b6, 0xc1d6, 0xc1df, 0xc1f6, +0xc1f8, 0xc4a1, 0xc5cd, 0xc6ae, 0xc7cf, 0xc7d1, 0xc7d2, 0xc7d8, 0xc7e5, 0xc8ad}; + +static const uint16_t commonChars_big5[] = { +// TODO: This set of data comes from the character frequency- +// of-occurrence analysis tool. The data needs to be moved +// into a resource and loaded from there. +0xa140, 0xa141, 0xa142, 0xa143, 0xa147, 0xa149, 0xa175, 0xa176, 0xa440, 0xa446, +0xa447, 0xa448, 0xa451, 0xa454, 0xa457, 0xa464, 0xa46a, 0xa46c, 0xa477, 0xa4a3, +0xa4a4, 0xa4a7, 0xa4c1, 0xa4ce, 0xa4d1, 0xa4df, 0xa4e8, 0xa4fd, 0xa540, 0xa548, +0xa558, 0xa569, 0xa5cd, 0xa5e7, 0xa657, 0xa661, 0xa662, 0xa668, 0xa670, 0xa6a8, +0xa6b3, 0xa6b9, 0xa6d3, 0xa6db, 0xa6e6, 0xa6f2, 0xa740, 0xa751, 0xa759, 0xa7da, +0xa8a3, 0xa8a5, 0xa8ad, 0xa8d1, 0xa8d3, 0xa8e4, 0xa8fc, 0xa9c0, 0xa9d2, 0xa9f3, +0xaa6b, 0xaaba, 0xaabe, 0xaacc, 0xaafc, 0xac47, 0xac4f, 0xacb0, 0xacd2, 0xad59, +0xaec9, 0xafe0, 0xb0ea, 0xb16f, 0xb2b3, 0xb2c4, 0xb36f, 0xb44c, 0xb44e, 0xb54c, +0xb5a5, 0xb5bd, 0xb5d0, 0xb5d8, 0xb671, 0xb7ed, 0xb867, 0xb944, 0xbad8, 0xbb44, +0xbba1, 0xbdd1, 0xc2c4, 0xc3b9, 0xc440, 0xc45f}; + +static const uint16_t commonChars_gb_18030[] = { +// TODO: This set of data comes from the character frequency- +// of-occurrence analysis tool. The data needs to be moved +// into a resource and loaded from there. +0xa1a1, 0xa1a2, 0xa1a3, 0xa1a4, 0xa1b0, 0xa1b1, 0xa1f1, 0xa1f3, 0xa3a1, 0xa3ac, +0xa3ba, 0xb1a8, 0xb1b8, 0xb1be, 0xb2bb, 0xb3c9, 0xb3f6, 0xb4f3, 0xb5bd, 0xb5c4, +0xb5e3, 0xb6af, 0xb6d4, 0xb6e0, 0xb7a2, 0xb7a8, 0xb7bd, 0xb7d6, 0xb7dd, 0xb8b4, +0xb8df, 0xb8f6, 0xb9ab, 0xb9c9, 0xb9d8, 0xb9fa, 0xb9fd, 0xbacd, 0xbba7, 0xbbd6, +0xbbe1, 0xbbfa, 0xbcbc, 0xbcdb, 0xbcfe, 0xbdcc, 0xbecd, 0xbedd, 0xbfb4, 0xbfc6, +0xbfc9, 0xc0b4, 0xc0ed, 0xc1cb, 0xc2db, 0xc3c7, 0xc4dc, 0xc4ea, 0xc5cc, 0xc6f7, +0xc7f8, 0xc8ab, 0xc8cb, 0xc8d5, 0xc8e7, 0xc9cf, 0xc9fa, 0xcab1, 0xcab5, 0xcac7, +0xcad0, 0xcad6, 0xcaf5, 0xcafd, 0xccec, 0xcdf8, 0xceaa, 0xcec4, 0xced2, 0xcee5, +0xcfb5, 0xcfc2, 0xcfd6, 0xd0c2, 0xd0c5, 0xd0d0, 0xd0d4, 0xd1a7, 0xd2aa, 0xd2b2, +0xd2b5, 0xd2bb, 0xd2d4, 0xd3c3, 0xd3d0, 0xd3fd, 0xd4c2, 0xd4da, 0xd5e2, 0xd6d0}; + +static int32_t binarySearch(const uint16_t *array, int32_t len, uint16_t value) +{ + int32_t start = 0, end = len-1; + int32_t mid = (start+end)/2; + + while(start <= end) { + if(array[mid] == value) { + return mid; + } + + if(array[mid] < value){ + start = mid+1; + } else { + end = mid-1; + } + + mid = (start+end)/2; + } + + return -1; +} + +IteratedChar::IteratedChar() : +charValue(0), index(-1), nextIndex(0), error(false), done(false) +{ + // nothing else to do. +} + +/*void IteratedChar::reset() +{ + charValue = 0; + index = -1; + nextIndex = 0; + error = false; + done = false; +}*/ + +int32_t IteratedChar::nextByte(InputText *det) +{ + if (nextIndex >= det->fRawLength) { + done = true; + + return -1; + } + + return det->fRawInput[nextIndex++]; +} + +CharsetRecog_mbcs::~CharsetRecog_mbcs() +{ + // nothing to do. +} + +int32_t CharsetRecog_mbcs::match_mbcs(InputText *det, const uint16_t commonChars[], int32_t commonCharsLen) const { + int32_t doubleByteCharCount = 0; + int32_t commonCharCount = 0; + int32_t badCharCount = 0; + int32_t totalCharCount = 0; + int32_t confidence = 0; + IteratedChar iter; + + while (nextChar(&iter, det)) { + totalCharCount++; + + if (iter.error) { + badCharCount++; + } else { + if (iter.charValue > 0xFF) { + doubleByteCharCount++; + + if (commonChars != 0) { + if (binarySearch(commonChars, commonCharsLen, static_cast<uint16_t>(iter.charValue)) >= 0){ + commonCharCount += 1; + } + } + } + } + + + if (badCharCount >= 2 && badCharCount*5 >= doubleByteCharCount) { + // Bail out early if the byte data is not matching the encoding scheme. + // break detectBlock; + return confidence; + } + } + + if (doubleByteCharCount <= 10 && badCharCount == 0) { + // Not many multi-byte chars. + if (doubleByteCharCount == 0 && totalCharCount < 10) { + // There weren't any multibyte sequences, and there was a low density of non-ASCII single bytes. + // We don't have enough data to have any confidence. + // Statistical analysis of single byte non-ASCII characters would probably help here. + confidence = 0; + } + else { + // ASCII or ISO file? It's probably not our encoding, + // but is not incompatible with our encoding, so don't give it a zero. + confidence = 10; + } + + return confidence; + } + + // + // No match if there are too many characters that don't fit the encoding scheme. + // (should we have zero tolerance for these?) + // + if (doubleByteCharCount < 20*badCharCount) { + confidence = 0; + + return confidence; + } + + if (commonChars == 0) { + // We have no statistics on frequently occurring characters. + // Assess confidence purely on having a reasonable number of + // multi-byte characters (the more the better) + confidence = 30 + doubleByteCharCount - 20*badCharCount; + + if (confidence > 100) { + confidence = 100; + } + } else { + // + // Frequency of occurrence statistics exist. + // + + double maxVal = log((double)doubleByteCharCount / 4); /*(float)?*/ + double scaleFactor = 90.0 / maxVal; + confidence = (int32_t)(log((double)commonCharCount+1) * scaleFactor + 10.0); + + confidence = min(confidence, 100); + } + + if (confidence < 0) { + confidence = 0; + } + + return confidence; +} + +CharsetRecog_sjis::~CharsetRecog_sjis() +{ + // nothing to do +} + +UBool CharsetRecog_sjis::nextChar(IteratedChar* it, InputText* det) const { + it->index = it->nextIndex; + it->error = false; + + int32_t firstByte = it->charValue = it->nextByte(det); + + if (firstByte < 0) { + return false; + } + + if (firstByte <= 0x7F || (firstByte > 0xA0 && firstByte <= 0xDF)) { + return true; + } + + int32_t secondByte = it->nextByte(det); + if (secondByte >= 0) { + it->charValue = (firstByte << 8) | secondByte; + } + // else we'll handle the error later. + + if (! ((secondByte >= 0x40 && secondByte <= 0x7F) || (secondByte >= 0x80 && secondByte <= 0xFE))) { + // Illegal second byte value. + it->error = true; + } + + return true; +} + +UBool CharsetRecog_sjis::match(InputText* det, CharsetMatch *results) const { + int32_t confidence = match_mbcs(det, commonChars_sjis, UPRV_LENGTHOF(commonChars_sjis)); + results->set(det, this, confidence); + return (confidence > 0); +} + +const char *CharsetRecog_sjis::getName() const +{ + return "Shift_JIS"; +} + +const char *CharsetRecog_sjis::getLanguage() const +{ + return "ja"; +} + +CharsetRecog_euc::~CharsetRecog_euc() +{ + // nothing to do +} + +UBool CharsetRecog_euc::nextChar(IteratedChar* it, InputText* det) const { + int32_t firstByte = 0; + int32_t secondByte = 0; + int32_t thirdByte = 0; + + it->index = it->nextIndex; + it->error = false; + firstByte = it->charValue = it->nextByte(det); + + if (firstByte < 0) { + // Ran off the end of the input data + return false; + } + + if (firstByte <= 0x8D) { + // single byte char + return true; + } + + secondByte = it->nextByte(det); + if (secondByte >= 0) { + it->charValue = (it->charValue << 8) | secondByte; + } + // else we'll handle the error later. + + if (firstByte >= 0xA1 && firstByte <= 0xFE) { + // Two byte Char + if (secondByte < 0xA1) { + it->error = true; + } + + return true; + } + + if (firstByte == 0x8E) { + // Code Set 2. + // In EUC-JP, total char size is 2 bytes, only one byte of actual char value. + // In EUC-TW, total char size is 4 bytes, three bytes contribute to char value. + // We don't know which we've got. + // Treat it like EUC-JP. If the data really was EUC-TW, the following two + // bytes will look like a well formed 2 byte char. + if (secondByte < 0xA1) { + it->error = true; + } + + return true; + } + + if (firstByte == 0x8F) { + // Code set 3. + // Three byte total char size, two bytes of actual char value. + thirdByte = it->nextByte(det); + it->charValue = (it->charValue << 8) | thirdByte; + + if (thirdByte < 0xa1) { + // Bad second byte or ran off the end of the input data with a non-ASCII first byte. + it->error = true; + } + } + + return true; + +} + +CharsetRecog_euc_jp::~CharsetRecog_euc_jp() +{ + // nothing to do +} + +const char *CharsetRecog_euc_jp::getName() const +{ + return "EUC-JP"; +} + +const char *CharsetRecog_euc_jp::getLanguage() const +{ + return "ja"; +} + +UBool CharsetRecog_euc_jp::match(InputText *det, CharsetMatch *results) const +{ + int32_t confidence = match_mbcs(det, commonChars_euc_jp, UPRV_LENGTHOF(commonChars_euc_jp)); + results->set(det, this, confidence); + return (confidence > 0); +} + +CharsetRecog_euc_kr::~CharsetRecog_euc_kr() +{ + // nothing to do +} + +const char *CharsetRecog_euc_kr::getName() const +{ + return "EUC-KR"; +} + +const char *CharsetRecog_euc_kr::getLanguage() const +{ + return "ko"; +} + +UBool CharsetRecog_euc_kr::match(InputText *det, CharsetMatch *results) const +{ + int32_t confidence = match_mbcs(det, commonChars_euc_kr, UPRV_LENGTHOF(commonChars_euc_kr)); + results->set(det, this, confidence); + return (confidence > 0); +} + +CharsetRecog_big5::~CharsetRecog_big5() +{ + // nothing to do +} + +UBool CharsetRecog_big5::nextChar(IteratedChar* it, InputText* det) const +{ + int32_t firstByte; + + it->index = it->nextIndex; + it->error = false; + firstByte = it->charValue = it->nextByte(det); + + if (firstByte < 0) { + return false; + } + + if (firstByte <= 0x7F || firstByte == 0xFF) { + // single byte character. + return true; + } + + int32_t secondByte = it->nextByte(det); + if (secondByte >= 0) { + it->charValue = (it->charValue << 8) | secondByte; + } + // else we'll handle the error later. + + if (secondByte < 0x40 || secondByte == 0x7F || secondByte == 0xFF) { + it->error = true; + } + + return true; +} + +const char *CharsetRecog_big5::getName() const +{ + return "Big5"; +} + +const char *CharsetRecog_big5::getLanguage() const +{ + return "zh"; +} + +UBool CharsetRecog_big5::match(InputText *det, CharsetMatch *results) const +{ + int32_t confidence = match_mbcs(det, commonChars_big5, UPRV_LENGTHOF(commonChars_big5)); + results->set(det, this, confidence); + return (confidence > 0); +} + +CharsetRecog_gb_18030::~CharsetRecog_gb_18030() +{ + // nothing to do +} + +UBool CharsetRecog_gb_18030::nextChar(IteratedChar* it, InputText* det) const { + int32_t firstByte = 0; + int32_t secondByte = 0; + int32_t thirdByte = 0; + int32_t fourthByte = 0; + + it->index = it->nextIndex; + it->error = false; + firstByte = it->charValue = it->nextByte(det); + + if (firstByte < 0) { + // Ran off the end of the input data + return false; + } + + if (firstByte <= 0x80) { + // single byte char + return true; + } + + secondByte = it->nextByte(det); + if (secondByte >= 0) { + it->charValue = (it->charValue << 8) | secondByte; + } + // else we'll handle the error later. + + if (firstByte >= 0x81 && firstByte <= 0xFE) { + // Two byte Char + if ((secondByte >= 0x40 && secondByte <= 0x7E) || (secondByte >=80 && secondByte <= 0xFE)) { + return true; + } + + // Four byte char + if (secondByte >= 0x30 && secondByte <= 0x39) { + thirdByte = it->nextByte(det); + + if (thirdByte >= 0x81 && thirdByte <= 0xFE) { + fourthByte = it->nextByte(det); + + if (fourthByte >= 0x30 && fourthByte <= 0x39) { + it->charValue = (it->charValue << 16) | (thirdByte << 8) | fourthByte; + + return true; + } + } + } + + // Something wasn't valid, or we ran out of data (-1). + it->error = true; + } + + return true; +} + +const char *CharsetRecog_gb_18030::getName() const +{ + return "GB18030"; +} + +const char *CharsetRecog_gb_18030::getLanguage() const +{ + return "zh"; +} + +UBool CharsetRecog_gb_18030::match(InputText *det, CharsetMatch *results) const +{ + int32_t confidence = match_mbcs(det, commonChars_gb_18030, UPRV_LENGTHOF(commonChars_gb_18030)); + results->set(det, this, confidence); + return (confidence > 0); +} + +U_NAMESPACE_END +#endif |