third_party/WebKit/Source/wtf/text/StringStatics.cpp

   1 /*
   2  * Copyright (C) 2010 Apple 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
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. 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 APPLE INC. ``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 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 "StringStatics.h"
  28
  29 #include "AtomicString.h"
  30 #include "StringImpl.h"
  31 #include "wtf/DynamicAnnotations.h"
  32 #include "wtf/MainThread.h"
  33 #include "wtf/StaticConstructors.h"
  34
  35 namespace WTF {
  36
  37 StringImpl* StringImpl::empty()
  38 {
  39     DEFINE_STATIC_LOCAL(StringImpl, emptyString, (ConstructEmptyString));
  40     WTF_ANNOTATE_BENIGN_RACE(&emptyString,
  41         "Benign race on the reference counter of a static string created by StringImpl::empty");
  42     return &emptyString;
  43 }
  44
  45 StringImpl* StringImpl::empty16Bit()
  46 {
  47     DEFINE_STATIC_LOCAL(StringImpl, emptyString, (ConstructEmptyString16Bit));
  48     WTF_ANNOTATE_BENIGN_RACE(&emptyString,
  49         "Benign race on the reference counter of a static string created by StringImpl::empty16Bit");
  50     return &emptyString;
  51 }
  52
  53 WTF_EXPORT DEFINE_GLOBAL(AtomicString, nullAtom)
  54 WTF_EXPORT DEFINE_GLOBAL(AtomicString, emptyAtom)
  55 WTF_EXPORT DEFINE_GLOBAL(AtomicString, starAtom)
  56 WTF_EXPORT DEFINE_GLOBAL(AtomicString, xmlAtom)
  57 WTF_EXPORT DEFINE_GLOBAL(AtomicString, xmlnsAtom)
  58 WTF_EXPORT DEFINE_GLOBAL(AtomicString, xlinkAtom)
  59
  60 // This is not an AtomicString because it is unlikely to be used as an
  61 // event/element/attribute name, so it shouldn't pollute the AtomicString hash
  62 // table.
  63 WTF_EXPORT DEFINE_GLOBAL(String, xmlnsWithColon)
  64
  65 NEVER_INLINE unsigned StringImpl::hashSlowCase() const
  66 {
  67     if (is8Bit())
  68         setHash(StringHasher::computeHashAndMaskTop8Bits(characters8(), m_length));
  69     else
  70         setHash(StringHasher::computeHashAndMaskTop8Bits(characters16(), m_length));
  71     return existingHash();
  72 }
  73
  74 void AtomicString::init()
  75 {
  76     ASSERT(isMainThread());
  77
  78     new (NotNull, (void*)&nullAtom) AtomicString;
  79     new (NotNull, (void*)&emptyAtom) AtomicString("");
  80 }
  81
  82 void StringStatics::init()
  83 {
  84     ASSERT(isMainThread());
  85
  86     // FIXME: These should be allocated at compile time.
  87     new (NotNull, (void*)&starAtom) AtomicString("*", AtomicString::ConstructFromLiteral);
  88     new (NotNull, (void*)&xmlAtom) AtomicString("xml", AtomicString::ConstructFromLiteral);
  89     new (NotNull, (void*)&xmlnsAtom) AtomicString("xmlns", AtomicString::ConstructFromLiteral);
  90     new (NotNull, (void*)&xlinkAtom) AtomicString("xlink", AtomicString::ConstructFromLiteral);
  91     new (NotNull, (void*)&xmlnsWithColon) String("xmlns:");
  92 }
  93
  94 }