runtime/Identifier.h

   1 /*
   2  *  Copyright (C) 2003, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
   3  *
   4  *  This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Library General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2 of the License, or (at your option) any later version.
   8  *
   9  *  This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Library General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU Library General Public License
  15  *  along with this library; see the file COPYING.LIB.  If not, write to
  16  *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  *  Boston, MA 02110-1301, USA.
  18  *
  19  */
  20
  21 #ifndef Identifier_h
  22 #define Identifier_h
  23
  24 #include "JSGlobalData.h"
  25 #include "ThreadSpecific.h"
  26 #include "UString.h"
  27 #include <wtf/text/CString.h>
  28
  29 namespace JSC {
  30
  31     class ExecState;
  32
  33     class Identifier {
  34         friend class Structure;
  35     public:
  36         Identifier() { }
  37
  38         Identifier(ExecState* exec, const char* s) : m_string(add(exec, s)) { } // Only to be used with string literals.
  39         Identifier(ExecState* exec, const UChar* s, int length) : m_string(add(exec, s, length)) { }
  40         Identifier(ExecState* exec, StringImpl* rep) : m_string(add(exec, rep)) { }
  41         Identifier(ExecState* exec, const UString& s) : m_string(add(exec, s.impl())) { }
  42
  43         Identifier(JSGlobalData* globalData, const char* s) : m_string(add(globalData, s)) { } // Only to be used with string literals.
  44         Identifier(JSGlobalData* globalData, const UChar* s, int length) : m_string(add(globalData, s, length)) { }
  45         Identifier(JSGlobalData* globalData, StringImpl* rep) : m_string(add(globalData, rep)) { }
  46         Identifier(JSGlobalData* globalData, const UString& s) : m_string(add(globalData, s.impl())) { }
  47
  48         const UString& ustring() const { return m_string; }
  49         StringImpl* impl() const { return m_string.impl(); }
  50
  51         const UChar* characters() const { return m_string.characters(); }
  52         int length() const { return m_string.length(); }
  53
  54         CString ascii() const { return m_string.ascii(); }
  55
  56         static Identifier from(ExecState* exec, unsigned y);
  57         static Identifier from(ExecState* exec, int y);
  58         static Identifier from(ExecState* exec, double y);
  59         static Identifier from(JSGlobalData*, unsigned y);
  60         static Identifier from(JSGlobalData*, int y);
  61         static Identifier from(JSGlobalData*, double y);
  62
  63         static uint32_t toUInt32(const UString&, bool& ok);
  64         uint32_t toUInt32(bool& ok) const { return toUInt32(m_string, ok); }
  65         unsigned toArrayIndex(bool& ok) const;
  66
  67         bool isNull() const { return m_string.isNull(); }
  68         bool isEmpty() const { return m_string.isEmpty(); }
  69
  70         friend bool operator==(const Identifier&, const Identifier&);
  71         friend bool operator!=(const Identifier&, const Identifier&);
  72
  73         friend bool operator==(const Identifier&, const char*);
  74         friend bool operator!=(const Identifier&, const char*);
  75
  76         static bool equal(const StringImpl*, const char*);
  77         static bool equal(const StringImpl*, const UChar*, unsigned length);
  78         static bool equal(const StringImpl* a, const StringImpl* b) { return ::equal(a, b); }
  79
  80         static PassRefPtr<StringImpl> add(ExecState*, const char*); // Only to be used with string literals.
  81         static PassRefPtr<StringImpl> add(JSGlobalData*, const char*); // Only to be used with string literals.
  82
  83     private:
  84         UString m_string;
  85
  86         static bool equal(const Identifier& a, const Identifier& b) { return a.m_string.impl() == b.m_string.impl(); }
  87         static bool equal(const Identifier& a, const char* b) { return equal(a.m_string.impl(), b); }
  88
  89         static PassRefPtr<StringImpl> add(ExecState*, const UChar*, int length);
  90         static PassRefPtr<StringImpl> add(JSGlobalData*, const UChar*, int length);
  91
  92         static PassRefPtr<StringImpl> add(ExecState* exec, StringImpl* r)
  93         {
  94 #ifndef NDEBUG
  95             checkCurrentIdentifierTable(exec);
  96 #endif
  97             if (r->isIdentifier())
  98                 return r;
  99             return addSlowCase(exec, r);
 100         }
 101         static PassRefPtr<StringImpl> add(JSGlobalData* globalData, StringImpl* r)
 102         {
 103 #ifndef NDEBUG
 104             checkCurrentIdentifierTable(globalData);
 105 #endif
 106             if (r->isIdentifier())
 107                 return r;
 108             return addSlowCase(globalData, r);
 109         }
 110
 111         static PassRefPtr<StringImpl> addSlowCase(ExecState*, StringImpl* r);
 112         static PassRefPtr<StringImpl> addSlowCase(JSGlobalData*, StringImpl* r);
 113
 114         static void checkCurrentIdentifierTable(ExecState*);
 115         static void checkCurrentIdentifierTable(JSGlobalData*);
 116     };
 117
 118     inline bool operator==(const Identifier& a, const Identifier& b)
 119     {
 120         return Identifier::equal(a, b);
 121     }
 122
 123     inline bool operator!=(const Identifier& a, const Identifier& b)
 124     {
 125         return !Identifier::equal(a, b);
 126     }
 127
 128     inline bool operator==(const Identifier& a, const char* b)
 129     {
 130         return Identifier::equal(a, b);
 131     }
 132
 133     inline bool operator!=(const Identifier& a, const char* b)
 134     {
 135         return !Identifier::equal(a, b);
 136     }
 137
 138     inline bool Identifier::equal(const StringImpl* r, const UChar* s, unsigned length)
 139     {
 140         if (r->length() != length)
 141             return false;
 142         const UChar* d = r->characters();
 143         for (unsigned i = 0; i != length; ++i)
 144             if (d[i] != s[i])
 145                 return false;
 146         return true;
 147     }
 148
 149     IdentifierTable* createIdentifierTable();
 150     void deleteIdentifierTable(IdentifierTable*);
 151
 152     struct IdentifierRepHash : PtrHash<RefPtr<StringImpl> > {
 153         static unsigned hash(const RefPtr<StringImpl>& key) { return key->existingHash(); }
 154         static unsigned hash(StringImpl* key) { return key->existingHash(); }
 155     };
 156
 157 } // namespace JSC
 158
 159 #endif // Identifier_h