BaseTools/Source/C/VfrCompile/Pccts/h/DLG_stream_input.h

   1
   2 /************************************************************/
   3 /*                                                                                                                      */
   4 /*              Predefined char stream: Input from (c++) stream.        */
   5 /*                                                                                                                      */
   6 /* By Hubert Holin (Hubert.Holin@Bigfoot.com), 1998.            */
   7 /*                                                                                                                      */
   8 /* This is completely free stuff, do whatever you want with     */
   9 /* it (but then, I will take no responsability for whatever     */
  10 /* may happen if you do either... caveat emptor!).                      */
  11 /*                                                                                                                      */
  12 /************************************************************/
  13
  14 #ifndef _DLG_STREAM_INPUT_H
  15 #define _DLG_STREAM_INPUT_H
  16
  17 #include "pccts_istream.h"
  18
  19 PCCTS_NAMESPACE_STD
  20
  21 #ifndef DLGX_H
  22 #include "DLexerBase.h"
  23 #endif
  24
  25
  26 // NOTES:       The semantics of the copy constructor
  27 //                      and the affectation operator may be unwaranted...
  28 //                      and the stream may not be reset.
  29 //
  30 //                      It would have been so much nicer for nextChar()
  31 //                      to throw (of for the DLGInputStream to change status)
  32 //                      upon hiting EOF than to return an "int"...
  33
  34 template        <
  35                                 class E,
  36                                 class T = ::std::char_traits<E>
  37                         >
  38 class DLG_stream_input : public DLGInputStream
  39 {
  40 public:
  41
  42                                                 DLG_stream_input(::std::basic_istream<E,T> * p_input_stream)
  43         :       input(p_input_stream)
  44         {
  45                 // nothing to do!
  46         };
  47
  48                                                 DLG_stream_input(const DLG_stream_input & a_recopier)
  49         :       input(a_recopier.input)
  50         {
  51                 // nothing to do!
  52         };
  53
  54         virtual                         ~DLG_stream_input()
  55         {
  56                 this->purge();  // bloody templarized lookup...
  57         };
  58
  59         DLG_stream_input        operator = (const DLG_stream_input & a_affecter)
  60         {
  61                 if (this != &a_affecter)
  62                 {
  63                         input = a_affecter.input;
  64                 }
  65
  66                 return(*this);
  67         };
  68
  69         virtual int                     nextChar()
  70         {
  71                 E       extracted_stuff;
  72
  73                 input->get(extracted_stuff);
  74
  75                 if      (*input)
  76                 {
  77                         return(int(extracted_stuff));
  78                 }
  79                 else
  80                 {
  81                         return(EOF);
  82                 }
  83         };
  84
  85 protected:
  86
  87         ::std::basic_istream<E,T> *     input;
  88
  89 private:
  90
  91         void    purge()
  92         {
  93                 // nothing to do!
  94         };
  95 };
  96
  97 #endif /* _DLG_STREAM_INPUT_H */
  98