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      1 /*
      2  * Copyright 2010, The Android Open Source Project
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions
      6  * are met:
      7  *  * Redistributions of source code must retain the above copyright
      8  *    notice, this list of conditions and the following disclaimer.
      9  *  * Redistributions in binary form must reproduce the above copyright
     10  *    notice, this list of conditions and the following disclaimer in the
     11  *    documentation and/or other materials provided with the distribution.
     12  *
     13  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
     14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
     17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
     21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     24  */
     25 
     26 #include "config.h"
     27 #include "Hyphenation.h"
     28 
     29 // For external hyphenation library.
     30 #include "hyphen.h"
     31 #include <androidfw/AssetManager.h>
     32 #include <wtf/text/CString.h>
     33 #include <wtf/text/WTFString.h>
     34 
     35 extern android::AssetManager* globalAssetManager();
     36 
     37 using namespace WTF;
     38 
     39 namespace WebCore {
     40 
     41 static HyphenDict* loadHyphenationDictionary()
     42 {
     43     android::AssetManager* am = globalAssetManager();
     44     // Only support English for now.
     45     android::Asset* a = am->open("webkit/hyph_en_US.dic",
     46         android::Asset::ACCESS_BUFFER);
     47     if (!a) {
     48         // Asset webkit/hyph_en_US.dic not found!
     49         return 0;
     50     }
     51     const CString dictContents = String(static_cast<const char*>(a->getBuffer(false)),
     52         a->getLength()).utf8();
     53     HyphenDict* dict = hnj_hyphen_load_from_buffer(dictContents.data(),
     54         dictContents.length());
     55     delete a;
     56 
     57     return dict;
     58 }
     59 
     60 bool canHyphenate(const AtomicString& /* localeIdentifier */)
     61 {
     62     // FIXME: Check that the locale identifier matches the available dictionary.
     63     return true;
     64 }
     65 
     66 size_t lastHyphenLocation(const UChar* characters, size_t length, size_t beforeIndex, const AtomicString& /* localeIdentifier */)
     67 {
     68     static const size_t minWordLen = 5;
     69     static const size_t maxWordLen = 100;
     70     if (beforeIndex <= 0 || length < minWordLen || length > maxWordLen)
     71         return 0;
     72 
     73     static HyphenDict* dict = loadHyphenationDictionary();
     74     if (!dict)
     75         return 0;
     76 
     77     char word[maxWordLen];
     78     size_t wordLength = 0;
     79     for (size_t i = 0; i < length; ++i) {
     80         const UChar ch = characters[i];
     81         // Only English for now.
     82         // To really make it language aware, we need something like language
     83         // detection or rely on the langAttr in the html element.  Though
     84         // seems right now the langAttr is not used or quite implemented in
     85         // webkit.
     86         if (!isASCIIAlpha(ch)) {
     87             // Bypass leading spaces.
     88             if (isASCIISpace(ch) && !wordLength)
     89               continue;
     90             return 0;
     91         }
     92         word[wordLength++] = ch;
     93     }
     94     if (wordLength < minWordLen)
     95         return 0;
     96 
     97     static const int extraBuffer = 5;
     98     const int leadingSpacesCount = length - wordLength;
     99     char hyphens[maxWordLen + extraBuffer];
    100     if (!hnj_hyphen_hyphenate(dict, word, wordLength, hyphens)) {
    101         for (size_t i = beforeIndex - 2 - leadingSpacesCount; i > 0; --i) {
    102             if (hyphens[i] & 1)
    103                 return i + 1 + leadingSpacesCount;
    104         }
    105     }
    106 
    107     return 0;
    108 }
    109 
    110 } // namespace WebCore
    111