include/wx/cmdargs.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        wx/cmdargs.h
   3 // Purpose:     declaration of wxCmdLineArgsArray helper class
   4 // Author:      Vadim Zeitlin
   5 // Created:     2007-11-12
   6 // RCS-ID:      $Id$
   7 // Copyright:   (c) 2007 Vadim Zeitlin <vadim@wxwindows.org>
   8 // Licence:     wxWindows licence
   9 ///////////////////////////////////////////////////////////////////////////////
  10
  11 #ifndef _WX_CMDARGS_H_
  12 #define _WX_CMDARGS_H_
  13
  14 #include "wx/arrstr.h"
  15
  16 // ----------------------------------------------------------------------------
  17 // wxCmdLineArgsArray: helper class used by wxApp::argv
  18 // ----------------------------------------------------------------------------
  19
  20 #if wxUSE_UNICODE
  21
  22 // this class is used instead of either "char **" or "wchar_t **" (neither of
  23 // which would be backwards compatible with all the existing code) for argv
  24 // field of wxApp
  25 //
  26 // as it's used for compatibility, it tries to look as much as traditional
  27 // (char **) argv as possible, in particular it provides implicit conversions
  28 // to "char **" and also array-like operator[]
  29 class WXDLLIMPEXP_BASE wxCmdLineArgsArray
  30 {
  31 public:
  32     wxCmdLineArgsArray() { m_argsA = NULL; m_argsW = NULL; }
  33
  34     template <typename T>
  35     wxCmdLineArgsArray& operator=(T **argv)
  36     {
  37         FreeArgs();
  38
  39         m_args.clear();
  40
  41         if ( argv )
  42         {
  43             while ( *argv )
  44                 m_args.push_back(*argv++);
  45         }
  46
  47         return *this;
  48     }
  49
  50     operator char**() const
  51     {
  52         if ( !m_argsA )
  53         {
  54             const size_t count = m_args.size();
  55             m_argsA = new char *[count];
  56             for ( size_t n = 0; n < count; n++ )
  57                 m_argsA[n] = wxStrdup(m_args[n].ToAscii());
  58         }
  59
  60         return m_argsA;
  61     }
  62
  63     operator wchar_t**() const
  64     {
  65         if ( !m_argsW )
  66         {
  67             const size_t count = m_args.size();
  68             m_argsW = new wchar_t *[count];
  69             for ( size_t n = 0; n < count; n++ )
  70                 m_argsW[n] = wxStrdup(m_args[n].wc_str());
  71         }
  72
  73         return m_argsW;
  74     }
  75
  76     // existing code does checks like "if ( argv )" and we want it to continue
  77     // to compile, so provide this conversion even if it is pretty dangerous
  78     operator bool() const
  79     {
  80         return !m_args.empty();
  81     }
  82
  83     // and the same for "if ( !argv )" checks
  84     bool operator!() const
  85     {
  86         return m_args.empty();
  87     }
  88
  89     wxString operator[](size_t n) const
  90     {
  91         return m_args[n];
  92     }
  93
  94     // we must provide this overload for g++ 3.4 which can't choose between
  95     // our operator[](size_t) and ::operator[](char**, int) otherwise
  96     wxString operator[](int n) const
  97     {
  98         return m_args[n];
  99     }
 100
 101
 102     // convenience methods, i.e. not existing only for backwards compatibility
 103
 104     // do we have any arguments at all?
 105     bool IsEmpty() const { return m_args.empty(); }
 106
 107     // access the arguments as a convenient array of wxStrings
 108     const wxArrayString& GetArguments() const { return m_args; }
 109
 110     ~wxCmdLineArgsArray()
 111     {
 112         FreeArgs();
 113     }
 114
 115 private:
 116     template <typename T>
 117     void Free(T **args)
 118     {
 119         if ( !args )
 120             return;
 121
 122         const size_t count = m_args.size();
 123         for ( size_t n = 0; n < count; n++ )
 124             free(args[n]);
 125
 126         delete [] args;
 127     }
 128
 129     void FreeArgs()
 130     {
 131         Free(m_argsA);
 132         Free(m_argsW);
 133     }
 134
 135     wxArrayString m_args;
 136     mutable char **m_argsA;
 137     mutable wchar_t **m_argsW;
 138
 139     wxDECLARE_NO_COPY_CLASS(wxCmdLineArgsArray);
 140 };
 141
 142 // provide global operator overload for compatibility with the existing code
 143 // doing things like "if ( condition && argv )"
 144 inline bool operator&&(bool cond, const wxCmdLineArgsArray& array)
 145 {
 146     return cond && !array.IsEmpty();
 147 }
 148
 149 #endif // wxUSE_UNICODE
 150
 151 #endif // _WX_CMDARGS_H_
 152