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-rw-r--r--intl/icu/source/common/usc_impl.cpp361
1 files changed, 361 insertions, 0 deletions
diff --git a/intl/icu/source/common/usc_impl.cpp b/intl/icu/source/common/usc_impl.cpp
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index 0000000000..cd5a4e5b8d
--- /dev/null
+++ b/intl/icu/source/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 char16_t *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 char16_t *src, int32_t length, UErrorCode *pErrorCode)
+{
+ UScriptRun *result = nullptr;
+
+ if (pErrorCode == nullptr || U_FAILURE(*pErrorCode)) {
+ return nullptr;
+ }
+
+ result = (UScriptRun *)uprv_malloc(sizeof (UScriptRun));
+
+ if (result == nullptr) {
+ *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
+ return nullptr;
+ }
+
+ uscript_setRunText(result, src, length, pErrorCode);
+
+ /* Release the UScriptRun if uscript_setRunText() returns an error */
+ if (U_FAILURE(*pErrorCode)) {
+ uprv_free(result);
+ result = nullptr;
+ }
+
+ return result;
+}
+
+U_CAPI void U_EXPORT2
+uscript_closeRun(UScriptRun *scriptRun)
+{
+ if (scriptRun != nullptr) {
+ uprv_free(scriptRun);
+ }
+}
+
+U_CAPI void U_EXPORT2
+uscript_resetRun(UScriptRun *scriptRun)
+{
+ if (scriptRun != nullptr) {
+ 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 char16_t *src, int32_t length, UErrorCode *pErrorCode)
+{
+ if (pErrorCode == nullptr || U_FAILURE(*pErrorCode)) {
+ return;
+ }
+
+ if (scriptRun == nullptr || length < 0 || ((src == nullptr) != (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 == nullptr || 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) {
+ char16_t 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) {
+ char16_t 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 != nullptr) {
+ *pRunStart = scriptRun->scriptStart;
+ }
+
+ if (pRunLimit != nullptr) {
+ *pRunLimit = scriptRun->scriptLimit;
+ }
+
+ if (pRunScript != nullptr) {
+ *pRunScript = scriptRun->scriptCode;
+ }
+
+ return true;
+}
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