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