xpcom/string/public/nsLiteralString.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is Mozilla.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications.
  19  * Portions created by the Initial Developer are Copyright (C) 2001
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Scott Collins <scc@mozilla.org> (original author)
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either of the GNU General Public License Version 2 or later (the "GPL"),
  27  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
  29  * of those above. If you wish to allow use of your version of this file only
  30  * under the terms of either the GPL or the LGPL, and not to allow others to
  31  * use your version of this file under the terms of the MPL, indicate your
  32  * decision by deleting the provisions above and replace them with the notice
  33  * and other provisions required by the GPL or the LGPL. If you do not delete
  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #ifndef nsLiteralString_h___
  40 #define nsLiteralString_h___
  41
  42 #ifndef nscore_h___
  43 #include "nscore.h"
  44 #endif
  45
  46 #ifndef nsDependentString_h___
  47 #include "nsDependentString.h"
  48 #endif
  49
  50
  51 #if 0
  52 inline
  53 const nsDependentString
  54 literal_string( const nsAString::char_type* aPtr )
  55   {
  56     return nsDependentString(aPtr);
  57   }
  58
  59 inline
  60 const nsDependentString
  61 literal_string( const nsAString::char_type* aPtr, PRUint32 aLength )
  62   {
  63     return nsDependentString(aPtr, aLength);
  64   }
  65
  66 inline
  67 const nsDependentCString
  68 literal_string( const nsACString::char_type* aPtr )
  69   {
  70     return nsDependentCString(aPtr);
  71   }
  72
  73 inline
  74 const nsDependentCString
  75 literal_string( const nsACString::char_type* aPtr, PRUint32 aLength )
  76   {
  77     return nsDependentCString(aPtr, aLength);
  78   }
  79 #endif
  80
  81 #if defined(HAVE_CPP_CHAR16_T) || defined(HAVE_CPP_2BYTE_WCHAR_T)
  82 #if defined(HAVE_CPP_CHAR16_T)
  83   //PR_STATIC_ASSERT(sizeof(char16_t) == 2);
  84   #define NS_LL(s)                                u##s
  85 #else
  86   //PR_STATIC_ASSERT(sizeof(wchar_t) == 2);
  87   #define NS_LL(s)                                L##s
  88 #endif
  89   #define NS_MULTILINE_LITERAL_STRING(s)          nsDependentString(reinterpret_cast<const nsAString::char_type*>(s), PRUint32((sizeof(s)/2)-1))
  90   #define NS_MULTILINE_LITERAL_STRING_INIT(n,s)   n(reinterpret_cast<const nsAString::char_type*>(s), PRUint32((sizeof(s)/2)-1))
  91   #define NS_NAMED_MULTILINE_LITERAL_STRING(n,s)  const nsDependentString n(reinterpret_cast<const nsAString::char_type*>(s), PRUint32((sizeof(s)/2)-1))
  92   typedef nsDependentString nsLiteralString;
  93 #else
  94   #define NS_LL(s)                                s
  95   #define NS_MULTILINE_LITERAL_STRING(s)          NS_ConvertASCIItoUTF16(s, PRUint32(sizeof(s)-1))
  96   #define NS_MULTILINE_LITERAL_STRING_INIT(n,s)   n(s, PRUint32(sizeof(s)-1))
  97   #define NS_NAMED_MULTILINE_LITERAL_STRING(n,s)  const NS_ConvertASCIItoUTF16 n(s, PRUint32(sizeof(s)-1))
  98   typedef NS_ConvertASCIItoUTF16 nsLiteralString;
  99 #endif
 100
 101 /*
 102  * Macro arguments used in concatenation or stringification won't be expanded.
 103  * Therefore, in order for |NS_L(FOO)| to work as expected (which is to expand
 104  * |FOO| before doing whatever |NS_L| needs to do to it) a helper macro needs
 105  * to be inserted in between to allow the macro argument to expand.
 106  * See "3.10.6 Separate Expansion of Macro Arguments" of the CPP manual for a
 107  * more accurate and precise explanation.
 108  */
 109
 110 #define NS_L(s)                                   NS_LL(s)
 111
 112 #define NS_LITERAL_STRING(s)                      static_cast<const nsAFlatString&>(NS_MULTILINE_LITERAL_STRING(NS_LL(s)))
 113 #define NS_LITERAL_STRING_INIT(n,s)               NS_MULTILINE_LITERAL_STRING_INIT(n, NS_LL(s))
 114 #define NS_NAMED_LITERAL_STRING(n,s)              NS_NAMED_MULTILINE_LITERAL_STRING(n, NS_LL(s))
 115
 116 #define NS_LITERAL_CSTRING(s)                     static_cast<const nsDependentCString&>(nsDependentCString(s, PRUint32(sizeof(s)-1)))
 117 #define NS_LITERAL_CSTRING_INIT(n,s)              n(s, PRUint32(sizeof(s)-1))
 118 #define NS_NAMED_LITERAL_CSTRING(n,s)             const nsDependentCString n(s, PRUint32(sizeof(s)-1))
 119
 120 typedef nsDependentCString nsLiteralCString;
 121
 122 #endif /* !defined(nsLiteralString_h___) */