libs/minisat/ParseUtils.h

   1 /************************************************************************************[ParseUtils.h]
   2 Copyright (c) 2003-2006, Niklas Een, Niklas Sorensson
   3 Copyright (c) 2007-2010, Niklas Sorensson
   4
   5 Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
   6 associated documentation files (the "Software"), to deal in the Software without restriction,
   7 including without limitation the rights to use, copy, modify, merge, publish, distribute,
   8 sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
   9 furnished to do so, subject to the following conditions:
  10
  11 The above copyright notice and this permission notice shall be included in all copies or
  12 substantial portions of the Software.
  13
  14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
  15 NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  16 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
  17 DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT
  18 OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  19 **************************************************************************************************/
  20
  21 #ifndef Minisat_ParseUtils_h
  22 #define Minisat_ParseUtils_h
  23
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26
  27 #include "XAlloc.h"
  28
  29 namespace Minisat {
  30
  31 //-------------------------------------------------------------------------------------------------
  32 // A simple buffered character stream class:
  33
  34
  35
  36 class StreamBuffer {
  37     unsigned char* buf;
  38     int            pos;
  39     int            size;
  40
  41     enum { buffer_size = 64*1024 };
  42
  43     virtual void assureLookahead() = 0;
  44
  45 public:
  46     virtual ~StreamBuffer() { }
  47
  48     int  operator *  () const { return (pos >= size) ? EOF : buf[pos]; }
  49     void operator ++ ()       { pos++; assureLookahead(); }
  50     int  position    () const { return pos; }
  51 };
  52
  53
  54 //-------------------------------------------------------------------------------------------------
  55 // End-of-file detection functions for StreamBuffer and char*:
  56
  57
  58 static inline bool isEof(StreamBuffer& in) { return *in == EOF;  }
  59 static inline bool isEof(const char*   in) { return *in == '\0'; }
  60
  61 //-------------------------------------------------------------------------------------------------
  62 // Generic parse functions parametrized over the input-stream type.
  63
  64
  65 template<class B>
  66 static void skipWhitespace(B& in) {
  67     while ((*in >= 9 && *in <= 13) || *in == 32)
  68         ++in; }
  69
  70
  71 template<class B>
  72 static void skipLine(B& in) {
  73     for (;;){
  74         if (isEof(in)) return;
  75         if (*in == '\n') { ++in; return; }
  76         ++in; } }
  77
  78
  79 template<class B>
  80 static int parseInt(B& in) {
  81     int     val = 0;
  82     bool    neg = false;
  83     skipWhitespace(in);
  84     if      (*in == '-') neg = true, ++in;
  85     else if (*in == '+') ++in;
  86     if (*in < '0' || *in > '9') fprintf(stderr, "PARSE ERROR! Unexpected char: %c\n", *in), exit(3);
  87     while (*in >= '0' && *in <= '9')
  88         val = val*10 + (*in - '0'),
  89         ++in;
  90     return neg ? -val : val; }
  91
  92
  93 // String matching: in case of a match the input iterator will be advanced the corresponding
  94 // number of characters.
  95 template<class B>
  96 static bool match(B& in, const char* str) {
  97     int i;
  98     for (i = 0; str[i] != '\0'; i++)
  99         if (in[i] != str[i])
 100             return false;
 101
 102     in += i;
 103
 104     return true;
 105 }
 106
 107 // String matching: consumes characters eagerly, but does not require random access iterator.
 108 template<class B>
 109 static bool eagerMatch(B& in, const char* str) {
 110     for (; *str != '\0'; ++str, ++in)
 111         if (*str != *in)
 112             return false;
 113     return true; }
 114
 115
 116 //=================================================================================================
 117 }
 118
 119 #endif