diff options
Diffstat (limited to 'thirdparty/icu4c/common/usc_impl.cpp')
-rw-r--r-- | thirdparty/icu4c/common/usc_impl.cpp | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/thirdparty/icu4c/common/usc_impl.cpp b/thirdparty/icu4c/common/usc_impl.cpp new file mode 100644 index 0000000000..111029b974 --- /dev/null +++ b/thirdparty/icu4c/common/usc_impl.cpp @@ -0,0 +1,361 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +********************************************************************** +* Copyright (C) 1999-2016, International Business Machines +* Corporation and others. All Rights Reserved. +********************************************************************** +* +* File USC_IMPL.C +* +* Modification History: +* +* Date Name Description +* 07/08/2002 Eric Mader Creation. +****************************************************************************** +*/ + +#include "unicode/uscript.h" +#include "usc_impl.h" +#include "cmemory.h" + +#define PAREN_STACK_DEPTH 32 + +#define MOD(sp) ((sp) % PAREN_STACK_DEPTH) +#define LIMIT_INC(sp) (((sp) < PAREN_STACK_DEPTH)? (sp) + 1 : PAREN_STACK_DEPTH) +#define INC(sp,count) (MOD((sp) + (count))) +#define INC1(sp) (INC(sp, 1)) +#define DEC(sp,count) (MOD((sp) + PAREN_STACK_DEPTH - (count))) +#define DEC1(sp) (DEC(sp, 1)) +#define STACK_IS_EMPTY(scriptRun) ((scriptRun)->pushCount <= 0) +#define STACK_IS_NOT_EMPTY(scriptRun) (! STACK_IS_EMPTY(scriptRun)) +#define TOP(scriptRun) ((scriptRun)->parenStack[(scriptRun)->parenSP]) +#define SYNC_FIXUP(scriptRun) ((scriptRun)->fixupCount = 0) + +struct ParenStackEntry +{ + int32_t pairIndex; + UScriptCode scriptCode; +}; + +struct UScriptRun +{ + int32_t textLength; + const UChar *textArray; + + int32_t scriptStart; + int32_t scriptLimit; + UScriptCode scriptCode; + + struct ParenStackEntry parenStack[PAREN_STACK_DEPTH]; + int32_t parenSP; + int32_t pushCount; + int32_t fixupCount; +}; + +static int8_t highBit(int32_t value); + +static const UChar32 pairedChars[] = { + 0x0028, 0x0029, /* ascii paired punctuation */ + 0x003c, 0x003e, + 0x005b, 0x005d, + 0x007b, 0x007d, + 0x00ab, 0x00bb, /* guillemets */ + 0x2018, 0x2019, /* general punctuation */ + 0x201c, 0x201d, + 0x2039, 0x203a, + 0x3008, 0x3009, /* chinese paired punctuation */ + 0x300a, 0x300b, + 0x300c, 0x300d, + 0x300e, 0x300f, + 0x3010, 0x3011, + 0x3014, 0x3015, + 0x3016, 0x3017, + 0x3018, 0x3019, + 0x301a, 0x301b +}; + +static void push(UScriptRun *scriptRun, int32_t pairIndex, UScriptCode scriptCode) +{ + scriptRun->pushCount = LIMIT_INC(scriptRun->pushCount); + scriptRun->fixupCount = LIMIT_INC(scriptRun->fixupCount); + + scriptRun->parenSP = INC1(scriptRun->parenSP); + scriptRun->parenStack[scriptRun->parenSP].pairIndex = pairIndex; + scriptRun->parenStack[scriptRun->parenSP].scriptCode = scriptCode; +} + +static void pop(UScriptRun *scriptRun) +{ + if (STACK_IS_EMPTY(scriptRun)) { + return; + } + + if (scriptRun->fixupCount > 0) { + scriptRun->fixupCount -= 1; + } + + scriptRun->pushCount -= 1; + scriptRun->parenSP = DEC1(scriptRun->parenSP); + + /* If the stack is now empty, reset the stack + pointers to their initial values. + */ + if (STACK_IS_EMPTY(scriptRun)) { + scriptRun->parenSP = -1; + } +} + +static void fixup(UScriptRun *scriptRun, UScriptCode scriptCode) +{ + int32_t fixupSP = DEC(scriptRun->parenSP, scriptRun->fixupCount); + + while (scriptRun->fixupCount-- > 0) { + fixupSP = INC1(fixupSP); + scriptRun->parenStack[fixupSP].scriptCode = scriptCode; + } +} + +static int8_t +highBit(int32_t value) +{ + int8_t bit = 0; + + if (value <= 0) { + return -32; + } + + if (value >= 1 << 16) { + value >>= 16; + bit += 16; + } + + if (value >= 1 << 8) { + value >>= 8; + bit += 8; + } + + if (value >= 1 << 4) { + value >>= 4; + bit += 4; + } + + if (value >= 1 << 2) { + value >>= 2; + bit += 2; + } + + if (value >= 1 << 1) { + //value >>= 1; + bit += 1; + } + + return bit; +} + +static int32_t +getPairIndex(UChar32 ch) +{ + int32_t pairedCharCount = UPRV_LENGTHOF(pairedChars); + int32_t pairedCharPower = 1 << highBit(pairedCharCount); + int32_t pairedCharExtra = pairedCharCount - pairedCharPower; + + int32_t probe = pairedCharPower; + int32_t pairIndex = 0; + + if (ch >= pairedChars[pairedCharExtra]) { + pairIndex = pairedCharExtra; + } + + while (probe > (1 << 0)) { + probe >>= 1; + + if (ch >= pairedChars[pairIndex + probe]) { + pairIndex += probe; + } + } + + if (pairedChars[pairIndex] != ch) { + pairIndex = -1; + } + + return pairIndex; +} + +static UBool +sameScript(UScriptCode scriptOne, UScriptCode scriptTwo) +{ + return scriptOne <= USCRIPT_INHERITED || scriptTwo <= USCRIPT_INHERITED || scriptOne == scriptTwo; +} + +U_CAPI UScriptRun * U_EXPORT2 +uscript_openRun(const UChar *src, int32_t length, UErrorCode *pErrorCode) +{ + UScriptRun *result = NULL; + + if (pErrorCode == NULL || U_FAILURE(*pErrorCode)) { + return NULL; + } + + result = (UScriptRun *)uprv_malloc(sizeof (UScriptRun)); + + if (result == NULL) { + *pErrorCode = U_MEMORY_ALLOCATION_ERROR; + return NULL; + } + + uscript_setRunText(result, src, length, pErrorCode); + + /* Release the UScriptRun if uscript_setRunText() returns an error */ + if (U_FAILURE(*pErrorCode)) { + uprv_free(result); + result = NULL; + } + + return result; +} + +U_CAPI void U_EXPORT2 +uscript_closeRun(UScriptRun *scriptRun) +{ + if (scriptRun != NULL) { + uprv_free(scriptRun); + } +} + +U_CAPI void U_EXPORT2 +uscript_resetRun(UScriptRun *scriptRun) +{ + if (scriptRun != NULL) { + scriptRun->scriptStart = 0; + scriptRun->scriptLimit = 0; + scriptRun->scriptCode = USCRIPT_INVALID_CODE; + scriptRun->parenSP = -1; + scriptRun->pushCount = 0; + scriptRun->fixupCount = 0; + } +} + +U_CAPI void U_EXPORT2 +uscript_setRunText(UScriptRun *scriptRun, const UChar *src, int32_t length, UErrorCode *pErrorCode) +{ + if (pErrorCode == NULL || U_FAILURE(*pErrorCode)) { + return; + } + + if (scriptRun == NULL || length < 0 || ((src == NULL) != (length == 0))) { + *pErrorCode = U_ILLEGAL_ARGUMENT_ERROR; + return; + } + + scriptRun->textArray = src; + scriptRun->textLength = length; + + uscript_resetRun(scriptRun); +} + +U_CAPI UBool U_EXPORT2 +uscript_nextRun(UScriptRun *scriptRun, int32_t *pRunStart, int32_t *pRunLimit, UScriptCode *pRunScript) +{ + UErrorCode error = U_ZERO_ERROR; + + /* if we've fallen off the end of the text, we're done */ + if (scriptRun == NULL || scriptRun->scriptLimit >= scriptRun->textLength) { + return FALSE; + } + + SYNC_FIXUP(scriptRun); + scriptRun->scriptCode = USCRIPT_COMMON; + + for (scriptRun->scriptStart = scriptRun->scriptLimit; scriptRun->scriptLimit < scriptRun->textLength; scriptRun->scriptLimit += 1) { + UChar high = scriptRun->textArray[scriptRun->scriptLimit]; + UChar32 ch = high; + UScriptCode sc; + int32_t pairIndex; + + /* + * if the character is a high surrogate and it's not the last one + * in the text, see if it's followed by a low surrogate + */ + if (high >= 0xD800 && high <= 0xDBFF && scriptRun->scriptLimit < scriptRun->textLength - 1) { + UChar low = scriptRun->textArray[scriptRun->scriptLimit + 1]; + + /* + * if it is followed by a low surrogate, + * consume it and form the full character + */ + if (low >= 0xDC00 && low <= 0xDFFF) { + ch = (high - 0xD800) * 0x0400 + low - 0xDC00 + 0x10000; + scriptRun->scriptLimit += 1; + } + } + + sc = uscript_getScript(ch, &error); + pairIndex = getPairIndex(ch); + + /* + * Paired character handling: + * + * if it's an open character, push it onto the stack. + * if it's a close character, find the matching open on the + * stack, and use that script code. Any non-matching open + * characters above it on the stack will be poped. + */ + if (pairIndex >= 0) { + if ((pairIndex & 1) == 0) { + push(scriptRun, pairIndex, scriptRun->scriptCode); + } else { + int32_t pi = pairIndex & ~1; + + while (STACK_IS_NOT_EMPTY(scriptRun) && TOP(scriptRun).pairIndex != pi) { + pop(scriptRun); + } + + if (STACK_IS_NOT_EMPTY(scriptRun)) { + sc = TOP(scriptRun).scriptCode; + } + } + } + + if (sameScript(scriptRun->scriptCode, sc)) { + if (scriptRun->scriptCode <= USCRIPT_INHERITED && sc > USCRIPT_INHERITED) { + scriptRun->scriptCode = sc; + + fixup(scriptRun, scriptRun->scriptCode); + } + + /* + * if this character is a close paired character, + * pop the matching open character from the stack + */ + if (pairIndex >= 0 && (pairIndex & 1) != 0) { + pop(scriptRun); + } + } else { + /* + * if the run broke on a surrogate pair, + * end it before the high surrogate + */ + if (ch >= 0x10000) { + scriptRun->scriptLimit -= 1; + } + + break; + } + } + + + if (pRunStart != NULL) { + *pRunStart = scriptRun->scriptStart; + } + + if (pRunLimit != NULL) { + *pRunLimit = scriptRun->scriptLimit; + } + + if (pRunScript != NULL) { + *pRunScript = scriptRun->scriptCode; + } + + return TRUE; +} |