The Tor Browser: comparison gfx/thebes/gfxScriptItemizer.cpp

--1:000000000000
+:25fbf66b24ad
+/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* 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/. */
+/*
+* This file is based on usc_impl.c from ICU 4.2.0.1, slightly adapted
+* for use within Mozilla Gecko, separate from a standard ICU build.
+*
+* The original ICU license of the code follows:
+*
+* ICU License - ICU 1.8.1 and later
+*
+* COPYRIGHT AND PERMISSION NOTICE
+*
+* Copyright (c) 1995-2009 International Business Machines Corporation and
+* others
+*
+* All rights reserved.
+*
+* Permission is hereby granted, free of charge, to any person obtaining a
+* copy of this software and associated documentation files (the "Software"),
+* to deal in the Software without restriction, including without limitation
+* the rights to use, copy, modify, merge, publish, distribute, and/or sell
+* copies of the Software, and to permit persons to whom the Software is
+* furnished to do so, provided that the above copyright notice(s) and this
+* permission notice appear in all copies of the Software and that both the
+* above copyright notice(s) and this permission notice appear in supporting
+* documentation.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS.
+* IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS NOTICE
+* BE LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES,
+* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+* WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+* ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+* SOFTWARE.
+*
+* Except as contained in this notice, the name of a copyright holder shall
+* not be used in advertising or otherwise to promote the sale, use or other
+* dealings in this Software without prior written authorization of the
+* copyright holder.
+*
+* All trademarks and registered trademarks mentioned herein are the property
+* of their respective owners.
+*/
+#include "gfxScriptItemizer.h"
+#include "nsUnicodeProperties.h"
+#include "nsCharTraits.h"
+#include "harfbuzz/hb.h"
+#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() (pushCount <= 0)
+#define STACK_IS_NOT_EMPTY() (! STACK_IS_EMPTY())
+#define TOP() (parenStack[parenSP])
+#define SYNC_FIXUP() (fixupCount = 0)
+void
+gfxScriptItemizer::push(uint32_t endPairChar, int32_t scriptCode)
+{
+pushCount  = LIMIT_INC(pushCount);
+fixupCount = LIMIT_INC(fixupCount);
+parenSP = INC1(parenSP);
+parenStack[parenSP].endPairChar = endPairChar;
+parenStack[parenSP].scriptCode = scriptCode;
+}
+void
+gfxScriptItemizer::pop()
+{
+if (STACK_IS_EMPTY()) {
+return;
+}
+if (fixupCount > 0) {
+fixupCount -= 1;
+}
+pushCount -= 1;
+parenSP = DEC1(parenSP);
+/* If the stack is now empty, reset the stack
+pointers to their initial values.
+*/
+if (STACK_IS_EMPTY()) {
+parenSP = -1;
+}
+}
+void
+gfxScriptItemizer::fixup(int32_t scriptCode)
+{
+int32_t fixupSP = DEC(parenSP, fixupCount);
+while (fixupCount-- > 0) {
+fixupSP = INC1(fixupSP);
+parenStack[fixupSP].scriptCode = scriptCode;
+}
+}
+static inline bool
+SameScript(int32_t runScript, int32_t currCharScript)
+{
+return runScript <= MOZ_SCRIPT_INHERITED ||
+currCharScript <= MOZ_SCRIPT_INHERITED ||
+currCharScript == runScript;
+}
+// Return whether the char has a mirrored-pair counterpart.
+// NOTE that this depends on the implementation of nsCharProps records in
+// nsUnicodeProperties, and may need to be updated if those structures change
+static inline bool
+HasMirroredChar(uint32_t aCh)
+{
+return GetCharProps1(aCh).mMirrorOffsetIndex != 0;
+}
+gfxScriptItemizer::gfxScriptItemizer(const char16_t *src, uint32_t length)
+: textPtr(src), textLength(length)
+{
+reset();
+}
+void
+gfxScriptItemizer::SetText(const char16_t *src, uint32_t length)
+{
+textPtr  = src;
+textLength = length;
+reset();
+}
+bool
+gfxScriptItemizer::Next(uint32_t& aRunStart, uint32_t& aRunLimit,
+int32_t& aRunScript)
+{
+/* if we've fallen off the end of the text, we're done */
+if (scriptLimit >= textLength) {
+return false;
+}
+SYNC_FIXUP();
+scriptCode = MOZ_SCRIPT_COMMON;
+for (scriptStart = scriptLimit; scriptLimit < textLength; scriptLimit += 1) {
+uint32_t ch;
+int32_t sc;
+uint32_t startOfChar = scriptLimit;
+ch = textPtr[scriptLimit];
+/* decode UTF-16 (may be surrogate pair) */
+if (NS_IS_HIGH_SURROGATE(ch) && scriptLimit < textLength - 1) {
+uint32_t low = textPtr[scriptLimit + 1];
+if (NS_IS_LOW_SURROGATE(low)) {
+ch = SURROGATE_TO_UCS4(ch, low);
+scriptLimit += 1;
+}
+}
+// Get the nsCharProps2 record for the current character,
+// so we can read the script and (if needed) the gen category
+// without needing to do two multi-level lookups.
+// NOTE that this means we're relying on an implementation detail
+// of the nsUnicodeProperties tables, and might have to revise this
+// if the nsCharProps records used there are modified in future.
+const nsCharProps2& charProps = GetCharProps2(ch);
+// Initialize gc to UNASSIGNED; we'll only set it to the true GC
+// if the character has script=COMMON, otherwise we don't care.
+uint8_t gc = HB_UNICODE_GENERAL_CATEGORY_UNASSIGNED;
+sc = charProps.mScriptCode;
+if (sc == MOZ_SCRIPT_COMMON) {
+/*
+* 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 popped.
+*
+* We only do this if the script is COMMON; for chars with
+* specific script assignments, we just use them as-is.
+*/
+gc = charProps.mCategory;
+if (gc == HB_UNICODE_GENERAL_CATEGORY_OPEN_PUNCTUATION) {
+uint32_t endPairChar = mozilla::unicode::GetMirroredChar(ch);
+if (endPairChar != ch) {
+push(endPairChar, scriptCode);
+}
+} else if (gc == HB_UNICODE_GENERAL_CATEGORY_CLOSE_PUNCTUATION &&
+HasMirroredChar(ch))
+{
+while (STACK_IS_NOT_EMPTY() && TOP().endPairChar != ch) {
+pop();
+}
+if (STACK_IS_NOT_EMPTY()) {
+sc = TOP().scriptCode;
+}
+}
+}
+if (SameScript(scriptCode, sc)) {
+if (scriptCode <= MOZ_SCRIPT_INHERITED &&
+sc > MOZ_SCRIPT_INHERITED)
+{
+scriptCode = sc;
+fixup(scriptCode);
+}
+/*
+* if this character is a close paired character,
+* pop the matching open character from the stack
+*/
+if (gc == HB_UNICODE_GENERAL_CATEGORY_CLOSE_PUNCTUATION &&
+HasMirroredChar(ch)) {
+pop();
+}
+} else {
+/*
+* reset scriptLimit in case it was advanced during reading a
+* multiple-code-unit character
+*/
+scriptLimit = startOfChar;
+break;
+}
+}
+aRunStart = scriptStart;
+aRunLimit = scriptLimit;
+aRunScript = scriptCode;
+return true;
+}

The Tor Browser / file comparison

comparison: gfx/thebes/gfxScriptItemizer.cpp

gfx/thebes/gfxScriptItemizer.cpp