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-rw-r--r--intl/lwbrk/WordBreaker.cpp218
1 files changed, 218 insertions, 0 deletions
diff --git a/intl/lwbrk/WordBreaker.cpp b/intl/lwbrk/WordBreaker.cpp
new file mode 100644
index 0000000000..269d084d93
--- /dev/null
+++ b/intl/lwbrk/WordBreaker.cpp
@@ -0,0 +1,218 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/intl/WordBreaker.h"
+#include "mozilla/StaticPrefs_layout.h"
+#include "nsComplexBreaker.h"
+#include "nsUnicodeProperties.h"
+
+using mozilla::intl::WordBreakClass;
+using mozilla::intl::WordBreaker;
+using mozilla::intl::WordRange;
+using mozilla::unicode::GetScriptCode;
+
+/*static*/
+already_AddRefed<WordBreaker> WordBreaker::Create() {
+ return RefPtr<WordBreaker>(new WordBreaker()).forget();
+}
+
+bool WordBreaker::BreakInBetween(const char16_t* aText1, uint32_t aTextLen1,
+ const char16_t* aText2, uint32_t aTextLen2) {
+ MOZ_ASSERT(nullptr != aText1, "null ptr");
+ MOZ_ASSERT(nullptr != aText2, "null ptr");
+
+ if (!aText1 || !aText2 || (0 == aTextLen1) || (0 == aTextLen2)) return false;
+
+ uint8_t c1 = GetClass(aText1[aTextLen1 - 1]);
+ uint8_t c2 = GetClass(aText2[0]);
+
+ if (c1 == c2 && kWbClassScriptioContinua == c1) {
+ nsAutoString text(aText1, aTextLen1);
+ text.Append(aText2, aTextLen2);
+ AutoTArray<uint8_t, 256> breakBefore;
+ breakBefore.SetLength(aTextLen1 + aTextLen2);
+ NS_GetComplexLineBreaks(text.get(), text.Length(), breakBefore.Elements());
+ bool ret = breakBefore[aTextLen1];
+ return ret;
+ }
+
+ return (c1 != c2);
+}
+
+#define IS_ASCII(c) (0 == (0xFF80 & (c)))
+#define ASCII_IS_ALPHA(c) \
+ ((('a' <= (c)) && ((c) <= 'z')) || (('A' <= (c)) && ((c) <= 'Z')))
+#define ASCII_IS_DIGIT(c) (('0' <= (c)) && ((c) <= '9'))
+#define ASCII_IS_SPACE(c) \
+ ((' ' == (c)) || ('\t' == (c)) || ('\r' == (c)) || ('\n' == (c)))
+#define IS_ALPHABETICAL_SCRIPT(c) ((c) < 0x2E80)
+
+// we change the beginning of IS_HAN from 0x4e00 to 0x3400 to relfect
+// Unicode 3.0
+#define IS_HAN(c) \
+ ((0x3400 <= (c)) && ((c) <= 0x9fff)) || ((0xf900 <= (c)) && ((c) <= 0xfaff))
+#define IS_KATAKANA(c) ((0x30A0 <= (c)) && ((c) <= 0x30FF))
+#define IS_HIRAGANA(c) ((0x3040 <= (c)) && ((c) <= 0x309F))
+#define IS_HALFWIDTHKATAKANA(c) ((0xFF60 <= (c)) && ((c) <= 0xFF9F))
+
+// Return true if aChar belongs to a SEAsian script that is written without
+// word spaces, so we need to use the "complex breaker" to find possible word
+// boundaries. (https://en.wikipedia.org/wiki/Scriptio_continua)
+// (How well this works depends on the level of platform support for finding
+// possible line breaks - or possible word boundaries - in the particular
+// script. Thai, at least, works pretty well on the major desktop OSes. If
+// the script is not supported by the platform, we just won't find any useful
+// boundaries.)
+static bool IsScriptioContinua(char16_t aChar) {
+ Script sc = GetScriptCode(aChar);
+ return sc == Script::THAI || sc == Script::MYANMAR || sc == Script::KHMER ||
+ sc == Script::JAVANESE || sc == Script::BALINESE ||
+ sc == Script::SUNDANESE || sc == Script::LAO;
+}
+
+/* static */
+WordBreakClass WordBreaker::GetClass(char16_t c) {
+ // begin of the hack
+
+ if (IS_ALPHABETICAL_SCRIPT(c)) {
+ if (IS_ASCII(c)) {
+ if (ASCII_IS_SPACE(c)) {
+ return kWbClassSpace;
+ }
+ if (ASCII_IS_ALPHA(c) || ASCII_IS_DIGIT(c) ||
+ (c == '_' && !StaticPrefs::layout_word_select_stop_at_underscore())) {
+ return kWbClassAlphaLetter;
+ }
+ return kWbClassPunct;
+ }
+ if (c == 0x00A0 /*NBSP*/) {
+ return kWbClassSpace;
+ }
+ if (GetGenCategory(c) == nsUGenCategory::kPunctuation) {
+ return kWbClassPunct;
+ }
+ if (IsScriptioContinua(c)) {
+ return kWbClassScriptioContinua;
+ }
+ return kWbClassAlphaLetter;
+ }
+ if (IS_HAN(c)) {
+ return kWbClassHanLetter;
+ }
+ if (IS_KATAKANA(c)) {
+ return kWbClassKatakanaLetter;
+ }
+ if (IS_HIRAGANA(c)) {
+ return kWbClassHiraganaLetter;
+ }
+ if (IS_HALFWIDTHKATAKANA(c)) {
+ return kWbClassHWKatakanaLetter;
+ }
+ if (GetGenCategory(c) == nsUGenCategory::kPunctuation) {
+ return kWbClassPunct;
+ }
+ if (IsScriptioContinua(c)) {
+ return kWbClassScriptioContinua;
+ }
+ return kWbClassAlphaLetter;
+}
+
+WordRange WordBreaker::FindWord(const char16_t* aText, uint32_t aTextLen,
+ uint32_t aOffset) {
+ WordRange range;
+ MOZ_ASSERT(nullptr != aText, "null ptr");
+ MOZ_ASSERT(0 != aTextLen, "len = 0");
+ MOZ_ASSERT(aOffset <= aTextLen, "aOffset > aTextLen");
+
+ range.mBegin = aTextLen + 1;
+ range.mEnd = aTextLen + 1;
+
+ if (!aText || aOffset > aTextLen) return range;
+
+ WordBreakClass c = GetClass(aText[aOffset]);
+ uint32_t i;
+ // Scan forward
+ range.mEnd--;
+ for (i = aOffset + 1; i <= aTextLen; i++) {
+ if (c != GetClass(aText[i])) {
+ range.mEnd = i;
+ break;
+ }
+ }
+
+ // Scan backward
+ range.mBegin = 0;
+ for (i = aOffset; i > 0; i--) {
+ if (c != GetClass(aText[i - 1])) {
+ range.mBegin = i;
+ break;
+ }
+ }
+
+ if (kWbClassScriptioContinua == c) {
+ // we pass the whole text segment to the complex word breaker to find a
+ // shorter answer
+ AutoTArray<uint8_t, 256> breakBefore;
+ breakBefore.SetLength(range.mEnd - range.mBegin);
+ NS_GetComplexLineBreaks(aText + range.mBegin, range.mEnd - range.mBegin,
+ breakBefore.Elements());
+
+ // Scan forward
+ for (i = aOffset + 1; i < range.mEnd; i++) {
+ if (breakBefore[i - range.mBegin]) {
+ range.mEnd = i;
+ break;
+ }
+ }
+
+ // Scan backward
+ for (i = aOffset; i > range.mBegin; i--) {
+ if (breakBefore[i - range.mBegin]) {
+ range.mBegin = i;
+ break;
+ }
+ }
+ }
+ return range;
+}
+
+int32_t WordBreaker::NextWord(const char16_t* aText, uint32_t aLen,
+ uint32_t aPos) {
+ WordBreakClass c1, c2;
+ uint32_t cur = aPos;
+ if (cur == aLen) {
+ return NS_WORDBREAKER_NEED_MORE_TEXT;
+ }
+ c1 = GetClass(aText[cur]);
+
+ for (cur++; cur < aLen; cur++) {
+ c2 = GetClass(aText[cur]);
+ if (c2 != c1) {
+ break;
+ }
+ }
+
+ if (kWbClassScriptioContinua == c1) {
+ // we pass the whole text segment to the complex word breaker to find a
+ // shorter answer
+ AutoTArray<uint8_t, 256> breakBefore;
+ breakBefore.SetLength(aLen - aPos);
+ NS_GetComplexLineBreaks(aText + aPos, aLen - aPos, breakBefore.Elements());
+ uint32_t i = 1;
+ while (i < cur - aPos && !breakBefore[i]) {
+ i++;
+ }
+ if (i < cur - aPos) {
+ return aPos + i;
+ }
+ }
+
+ if (cur == aLen) {
+ return NS_WORDBREAKER_NEED_MORE_TEXT;
+ }
+
+ MOZ_ASSERT(cur != aPos);
+ return cur;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-15 13:52:11 +0000