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      1 /*
      2  * Copyright (C) 2014 Google Inc. All rights reserved.
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions are
      6  * met:
      7  *
      8  *     * Redistributions of source code must retain the above copyright
      9  * notice, this list of conditions and the following disclaimer.
     10  *     * Redistributions in binary form must reproduce the above
     11  * copyright notice, this list of conditions and the following disclaimer
     12  * in the documentation and/or other materials provided with the
     13  * distribution.
     14  *     * Neither the name of Google Inc. nor the names of its
     15  * contributors may be used to endorse or promote products derived from
     16  * this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
     19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
     20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
     21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
     22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     23  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
     24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     29  */
     30 
     31 #ifndef Character_h
     32 #define Character_h
     33 
     34 #include "platform/PlatformExport.h"
     35 #include "platform/text/TextDirection.h"
     36 #include "platform/text/TextPath.h"
     37 #include "wtf/HashSet.h"
     38 #include "wtf/text/WTFString.h"
     39 #include "wtf/unicode/CharacterNames.h"
     40 
     41 namespace blink {
     42 
     43 class PLATFORM_EXPORT Character {
     44 public:
     45     static CodePath characterRangeCodePath(const LChar*, unsigned) { return SimplePath; }
     46     static CodePath characterRangeCodePath(const UChar*, unsigned len);
     47 
     48     static bool isCJKIdeograph(UChar32);
     49     static bool isCJKIdeographOrSymbol(UChar32);
     50 
     51     static unsigned expansionOpportunityCount(const LChar*, size_t length, TextDirection, bool& isAfterExpansion);
     52     static unsigned expansionOpportunityCount(const UChar*, size_t length, TextDirection, bool& isAfterExpansion);
     53 
     54     static bool treatAsSpace(UChar c) { return c == space || c == characterTabulation || c == newlineCharacter || c == noBreakSpace; }
     55     static bool treatAsZeroWidthSpace(UChar c) { return treatAsZeroWidthSpaceInComplexScript(c) || c == 0x200c || c == 0x200d; }
     56     static bool treatAsZeroWidthSpaceInComplexScript(UChar c) { return c < 0x20 || (c >= 0x7F && c < 0xA0) || c == softHyphen || c == zeroWidthSpace || (c >= 0x200e && c <= 0x200f) || (c >= 0x202a && c <= 0x202e) || c == zeroWidthNoBreakSpace || c == objectReplacementCharacter; }
     57     static bool canReceiveTextEmphasis(UChar32);
     58 
     59     static inline UChar normalizeSpaces(UChar character)
     60     {
     61         if (treatAsSpace(character))
     62             return space;
     63 
     64         if (treatAsZeroWidthSpace(character))
     65             return zeroWidthSpace;
     66 
     67         return character;
     68     }
     69 
     70     static inline bool isNormalizedCanvasSpaceCharacter(UChar c)
     71     {
     72         // According to specification all space characters should be replaced with 0x0020 space character.
     73         // http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#text-preparation-algorithm
     74         // The space characters according to specification are : U+0020, U+0009, U+000A, U+000C, and U+000D.
     75         // http://www.whatwg.org/specs/web-apps/current-work/multipage/common-microsyntaxes.html#space-character
     76         // This function returns true for 0x000B also, so that this is backward compatible.
     77         // Otherwise, the test LayoutTests/canvas/philip/tests/2d.text.draw.space.collapse.space.html will fail
     78         return c == 0x0009 || (c >= 0x000A && c <= 0x000D);
     79     }
     80 
     81     static String normalizeSpaces(const LChar*, unsigned length);
     82     static String normalizeSpaces(const UChar*, unsigned length);
     83 
     84 private:
     85     Character();
     86 };
     87 
     88 } // namespace blink
     89 
     90 #endif
     91