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/*************************************************************** 
File: COMMON.CPP              Copyright 1992 by Dlugosz Software 
part of the CMDL package for command-line parsing 
common functions for command-line argument derived classes 
This version may be used freely, with attribution. 
***************************************************************/ 
 
#include "usual.h" 
#include "cmdl.h" 
#include "scanner.h" 
#include  
#include  
 
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/*     post-processing                      */ 
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void cmdl::validate (unsigned fl) 
{ 
/* this virtual function is called for each argument after parseing is 
   complete.  It can be overriden in a derived class to do addtional tests. */ 
if ((flags&required) && !(flags&used)) { 
   // if required but not present 
   if (flags & noname) output ("error:  too few parameters\n"); 
   else foutput ("error:  parameter @ is required\n"); 
   exit (1); 
   } 
} 
 
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/*     parsing and extracting values        */ 
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bool cmdl::prelude() 
{ 
/* called by scan() functions for standard actions in parsing 
   a command line argument.   */ 
if ((flags&once) && (flags&used)) { 
   // if `once' flag set, make sure it is in fact only used once. 
   error= Duplicate; 
   return FALSE; 
   } 
flags |= used;  //mark as used. 
return TRUE; 
} 
 
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char* cmdl::getvalue (cmdlscan& s) 
{ 
/* this gets the associated value that follows a paramter.  At this 
   point, it is just a string.  The caller will take the result and 
   convert to the proper type and further analyse it. 
   Forms are: 
    1)    name=value 
    2)    name value 
    3)    namevalue 
    4)    value 
    #3 leaves it up the the primary parser (already done) 
   how to tell where the name leaves off and the value begins.  It 
   works for one-letter names, i.e.  -c10. 
    #2 is not allowed if the value is optional, since it could not 
   tell if the following token was the next parameter or the argument 
   of this one. 
    #4 is for positional parameters, where there is no name.  It is 
   necessary to distinguish between this and form 1 because the value 
   could begin with a '=' character. 
*/ 
 
if (!(flags & noname)) { //not a positional parameter 
   char ch= s.thischar(); 
   if (ch == '=') ++s;  //skip the '=' character 
   else { 
      //forms without a '=' character. 
      if (flags & valueoptional) { 
         //whitespace is considered no value 
         if (ch == ' ' || ch == '\t' || ch == '\n' || ch == '\0') 
            return 0; 
         } 
      s.skipws();  //skip any whitespace 
      } 
   } 
char* value= s.extract_string(); 
return value; 
} 
 
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bool cmdl::matchname (const char* s) 
{ 
/* this decides if `s' matches the name of this object */ 
if (s[1] == '\0') { 
   if (s[0] == cname) return TRUE; 
   } 
else { 
   if (!strcmp (s,sname)) return TRUE; 
   } 
return FALSE; 
} 
 
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