gnu/lib/libg++/g++-include/istream.h

   1 // This may look like C code, but it is really -*- C++ -*-
   2 /*
   3 Copyright (C) 1989 Free Software Foundation
   4     written by Doug Lea (dl@rocky.oswego.edu)
   5
   6 This file is part of GNU CC.
   7
   8 GNU CC is distributed in the hope that it will be useful,
   9 but WITHOUT ANY WARRANTY.  No author or distributor
  10 accepts responsibility to anyone for the consequences of using it
  11 or for whether it serves any particular purpose or works at all,
  12 unless he says so in writing.  Refer to the GNU CC General Public
  13 License for full details.
  14
  15 Everyone is granted permission to copy, modify and redistribute
  16 GNU CC, but only under the conditions described in the
  17 GNU CC General Public License.   A copy of this license is
  18 supposed to have been given to you along with GNU CC so you
  19 can know your rights and responsibilities.  It should be in a
  20 file named COPYING.  Among other things, the copyright notice
  21 and this notice must be preserved on all copies.
  22 */
  23
  24 /* *** Version 1.2 -- nearly 100% AT&T 1.2 compatible *** */
  25
  26 /* istream.h now separately includable */
  27
  28 #ifndef _istream_h
  29 #ifdef __GNUG__
  30 #pragma once
  31 #pragma interface
  32 #endif
  33 #define _istream_h 1
  34
  35
  36 #include <File.h>
  37 #include <streambuf.h>
  38 #include <filebuf.h>
  39 #include <Filebuf.h>
  40
  41 class whitespace                // a class used only to input and
  42 {                               // discard white space characters
  43   char filler;
  44 };
  45
  46 class ostream;
  47
  48 class istream
  49 {
  50   friend void   eatwhite(istream& s);
  51 protected:
  52   streambuf*    bp;
  53   state_value   state;           // _good/_eof/_fail/_bad
  54   ostream*      tied_to;
  55   char          skipws;
  56   char          ownbuf;
  57   void          _flush();
  58   char*         readline (int chunk_number, char terminator);
  59
  60 public:
  61                 istream(const char* filename, io_mode m, access_mode a,
  62                         int sk=1, ostream* t = 0);
  63                 istream(const char* filename, const char* m,
  64                         int sk=1, ostream* t = 0);
  65                 istream(int filedesc, io_mode m, int sk=1, ostream* t = 0);
  66                 istream(FILE* fileptr, int sk=1, ostream* t = 0);
  67                 istream(int sz, char* buf, int sk=1, ostream* t = 0);
  68                 istream(int filedesc, int sk=1, ostream* t = 0);
  69                 istream(int filedesc, char* buf, int buflen,
  70                         int sk, ostream* t = 0);
  71                 istream(streambuf* s, int sk=1, ostream* t = 0);
  72
  73                ~istream();
  74
  75   istream&      open(const char* filename, io_mode m, access_mode a);
  76   istream&      open(const char* filename, const char* m);
  77   istream&      open(int  filedesc, io_mode m);
  78   istream&      open(FILE* fileptr);
  79   istream&      open(const char* filenam, open_mode m);
  80
  81   istream&      close();
  82
  83   ostream*      tie(ostream* s);
  84   int           skip(int);
  85
  86 // stream status
  87
  88   int           rdstate();
  89   int           eof();
  90   int           fail();
  91   int           bad();
  92   int           good();
  93
  94 // other status queries
  95
  96   int           readable();
  97   int           writable();
  98   int           is_open();
  99
 100                 operator void*();
 101   int           operator !();
 102
 103   const char*   name();
 104
 105   char*         bufptr();
 106
 107 // error handling
 108
 109   void          error();
 110   void          clear(state_value f = _good); // poorly named
 111   void          set(state_value f); // set corresponding bit
 112   void          unset(state_value f); // clear corresponding bit
 113   istream&      failif(int cond);
 114
 115 // unformatted IO
 116
 117   istream&      get(char& c);
 118   istream&      unget(char c);
 119   istream&      putback(char c); // a synonym for unget
 120
 121   istream&      get    (char* s, int n, char terminator = '\n');
 122   istream&      getline(char* s, int n, char terminator = '\n');
 123   istream&      gets   (char **s, char terminator = '\n');
 124
 125
 126   istream&      operator >> (char&   c);
 127   istream&      operator >> (short&  n);
 128   istream&      operator >> (unsigned short& n);
 129   istream&      operator >> (int&    n);
 130   istream&      operator >> (unsigned int& n);
 131   istream&      operator >> (long&   n);
 132   istream&      operator >> (unsigned long& n);
 133 #ifdef __GNUG__
 134   istream&      operator >> (long long& n);
 135   istream&      operator >> (unsigned long long& n);
 136 #endif
 137   istream&      operator >> (float&  n);
 138   istream&      operator >> (double& n);
 139   istream&      operator >> (char*   s);
 140   istream&      operator >> (whitespace& w);
 141 };
 142
 143 // pre-declared streams
 144
 145 extern istream  cin;             // stdin
 146
 147 extern whitespace WS;            // for convenience
 148
 149 #if defined(__OPTIMIZE__) || defined(USE_LIBGXX_INLINES)
 150
 151
 152 inline void istream::clear(state_value flag)
 153 {
 154   state = flag;
 155 }
 156
 157 inline void istream::set(state_value flag)
 158 {
 159   state = state_value(int(state) | int(flag));
 160 }
 161
 162 inline void istream::unset(state_value flag)
 163 {
 164   state = state_value(int(state) & ~int(flag));
 165 }
 166
 167 inline int istream::rdstate()
 168 {
 169   return int(state);
 170 }
 171
 172 inline int istream::good()
 173 {
 174   return state == _good;
 175 }
 176
 177 inline int istream::eof()
 178 {
 179   return int(state) & int(_eof);
 180 }
 181
 182 inline int istream::fail()
 183 {
 184   return int(state) & int(_fail);
 185 }
 186
 187 inline int istream::bad()
 188 {
 189   return int(state) & int(_bad);
 190 }
 191
 192 inline istream::operator void*()
 193 {
 194   return (state == _good)? this : 0;
 195 }
 196
 197 inline int istream::operator !()
 198 {
 199   return (state != _good);
 200 }
 201
 202 inline istream& istream::failif(int cond)
 203 {
 204   if (cond) set(_fail); return *this;
 205 }
 206
 207 inline int istream::is_open()
 208 {
 209   return bp->is_open();
 210 }
 211
 212 inline int istream::readable()
 213 {
 214   return (bp != 0) && (bp->is_open()) && (state == _good);
 215 }
 216
 217 inline int istream::writable()
 218 {
 219   return 0;
 220 }
 221
 222
 223 inline char* istream::bufptr()
 224 {
 225   return bp->base;
 226 }
 227
 228
 229 inline istream& istream::close()
 230 {
 231   bp->close();  return *this;
 232 }
 233
 234
 235 inline int istream::skip(int sk)
 236 {
 237   int was = skipws; skipws = sk; return was;
 238 }
 239
 240
 241 inline istream& istream::unget(char c)
 242 {
 243   if (bp->sputbackc(c) == EOF) set(_fail); return *this;
 244 }
 245
 246 inline istream& istream::putback(char c)
 247 {
 248   if (bp->sputbackc(c) == EOF) set(_fail); return *this;
 249 }
 250
 251 inline void eatwhite(istream& s)
 252 {
 253   s >> WS;
 254 }
 255
 256 #endif
 257
 258
 259 #endif