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/*************************************************************** 
File: SCANNER.CPP             Copyright 1992 by Dlugosz Software 
part of the CMDL package for command-line parsing 
the scanner class, used as part of parsing the strings. 
This version may be used freely, with attribution. 
***************************************************************/ 
 
#include "usual.h" 
#include "cmdl.h" 
#include "scanner.h" 
#include  
#include  
 
/* /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ */ 
 
cmdlscan::cmdlscan (char* s) 
: s (s) 
{ 
link= 0;   // the root entry 
source= 0; // came from nowhere 
cursor= 0; // always start at the beginning of the string 
} 
 
/* /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ */ 
 
inline bool isws (char c) 
{ 
return c==' ' || c=='\t'; 
} 
 
/* /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ */ 
 
void cmdlscan::skipws() 
{  // stands for Skip Whitespace, in case you did not figure it out. 
while (isws(s[cursor])) cursor++; 
} 
 
/* /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ */ 
 
void cmdlscan::extract_word (char* buf, int len) 
{   // copy letters from string, until it reaches a blank or '='. 
len--;  //leave room for trailing nul 
for (;;) { 
   char ch= s[cursor]; 
   if (ch == '\n' || ch == '\0' || ch == ' ' || ch == '\t' || ch == '=') break;  //the end 
   *buf++ = ch; 
   len--; 
   cursor++; 
   if (len == 0) break;  //quit now anyway.  out of room. 
   } 
*buf= '\0'; 
} 
 
/* /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ */ 
 
char* cmdlscan::extract_string() 
{ 
const bufsize= 128; 
char buf[1+bufsize]; 
int pos= 0; 
char close= '\0';  //char used to delimit string (optional) 
char ch= s[cursor]; 
if (ch == '"' || ch == '\'') {  //look for quotes... 
   close= ch;                   //...and remember what close quote will be. 
   ++s; 
   } 
for (;;) { 
   ch= s[cursor]; 
   if (ch == '\0') break; 
   if (close) { //looking for closing quote 
      if (ch == close) { 
         cursor++; 
         break; 
         } 
      } 
   else { //looking for whitespace 
      if (ch == '\n' || ch == '\0' || ch == ' ' || ch == '\t') break; 
      } 
   buf[pos++] = ch; 
   cursor++; 
   if (pos == bufsize) break;  //quit now anyway.  out of room. 
   } 
buf[pos]= '\0'; 
char* result= new char [1+strlen(buf)]; 
strcpy (result, buf); 
return result; 
} 
 
/* /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\ */