args.c

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/*
 * 68K/386 32-bit C compiler.
 *
 * copyright (c) 1997, David Lindauer
 * 
 * This compiler is intended for educational use.  It may not be used
 * for profit without the express written consent of the author.
 *
 * It may be freely redistributed, as long as this notice remains intact
 * and either the original sources or derived sources 
 * are distributed along with any executables derived from the originals.
 *
 * The author is not responsible for any damages that may arise from use
 * of this software, either idirect or consequential.
 *
 * v1.35 March 1997
 * David Lindauer, [e-mail]
 *
 * Credits to Mathew Brandt for original K&R C compiler
 *
 */
#include <stdio.h>
#include <ctype.h>
#include "cmdline.h"
/*
 * This module handles command line arguments.  The main program defines
 * an array specifying what arguments are allowed and what the activity
 * should be for each argument and then calls parse_args giving it
 * argv and argc as arguments.  Parse-args dispatches any arguments it
 * finds to the action routine and then deletes the argument it found
 * from argv[]
 */
/*
 * The main program must define this array.  It customizes the types of
 * arguments that will be allowed
 *
 */
extern ARGLIST ArgList[];

static BOOL use_case;	/* Gets set for case sensitivity */

/* 
 * Function that unlinks the argument from che argv[] chain
 */
static void remove_arg(int pos, int *count, char *list[])
{
  int i;

  /* Decrement length of list */
  (*count)--;

  /* move items down */
  for (i=pos; i<*count; i++)
    list[i] = list[i+1];

}
/*
 * ompare two characters, ignoring case if necessary
 */
static BOOL cmatch(char t1, char t2)
{
  if (use_case)
    return(t1 == t2);

  return(toupper(t1) == toupper(t2));
}
/* Routine scans a string to see if any of the characters match
 *  the arguments, then dispatches to the action routine if so.
 */
/* Callbacks of the form
 *   void boolcallback( char selectchar, BOOL value)
 *   void switchcallback( char selectchar, BOOL value)  ;; value always true
 *   void stringcallback( char selectchar, char *string)
 */
static int scan_args(char *string, int index, char *arg)
{
  int i=-1;
  while (ArgList[++i].id) {
    switch( ArgList[i].mode) {
			case ARG_SWITCHSTRING:
              if (cmatch(string[index], ArgList[i].id)) {
		(* ArgList[i].routine)(string[index],&string[index]);
		 return (ARG_NEXTCHAR);
	      }
	      break;
      case ARG_SWITCH:
              if (cmatch(string[index], ArgList[i].id)) {
		(* ArgList[i].routine)(string[index],(char *)TRUE);
		 return (ARG_NEXTCHAR);
	      }
	      break;
      case ARG_BOOL:
	      if (cmatch(string[index], ArgList[i].id)) {
		if (string[0] == ARG_SEPTRUE)
		  (* ArgList[i].routine)(string[index],(char *)TRUE);
		else
		  (* ArgList[i].routine)(string[index],(char *)FALSE);
		return(ARG_NEXTCHAR);
	      }
	      break;
      case ARG_CONCATSTRING:
	      if (cmatch(string[index], ArgList[i].id)) {
		(* ArgList[i].routine)(string[index], string+index+1);
		return(ARG_NEXTARG);
	      }
	      break;
      case ARG_NOCONCATSTRING:
	      if (cmatch(string[index], ArgList[i].id)) {
		if (!arg)
		  return(ARG_NOARG);
                (* ArgList[i].routine)(string[index], arg);
                return(ARG_NEXTNOCAT);
              }
              break;
    }
  }
  return(ARG_NOMATCH);
}
/*
 * Main parse routine.  Scans for '-', then scan for arguments and
 * delete from the argv[] array if so.
 */
BOOL parse_args(int *argc, char *argv[], BOOL case_sensitive)
{
  int pos = 0;

  BOOL retval = TRUE;
  use_case = case_sensitive;

  while(++pos < *argc) {
    if ((argv[pos][0] == ARG_SEPSWITCH) || (argv[pos][0] == ARG_SEPFALSE)
          || (argv[pos][0] == ARG_SEPTRUE)) {
      int argmode;
      int index = 1;
      int done = FALSE;
      do {
        /* Scan the present arg */
        if (pos < *argc - 1)
          argmode = scan_args(argv[pos], index, argv[pos+1]);
        else
          argmode = scan_args(argv[pos], index, 0);

        switch(argmode) {
          case ARG_NEXTCHAR:
                  /* If it was a char, go to the next one */
                  if (!argv[pos][++index])
                    done = TRUE;
                  break;
          case ARG_NEXTNOCAT:
                  /* Otherwise if it was a nocat, remove the extra arg */
                  remove_arg(pos, argc, argv);
                  /* Fall through to NEXTARG */
          case ARG_NEXTARG:
                  /* Just a next arg, go do it */
                  done = TRUE;
                  break;
          case ARG_NOMATCH:
                  /* No such arg, spit an error  */
                  fprintf(stderr,"Invalid Arg: %s\n", argv[pos]);
                  done = TRUE;
                  retval = FALSE;
                  break;
          case ARG_NOARG:
                  /* Missing the arg for a CONCAT type, spit the error */
                  fprintf(stderr,"Missing string for Arg %s\n", argv[pos]);
                  done = TRUE;
                  retval = FALSE;
                  break;
        };

      } while (!done);
      /* We'll always get rid of the present arg
       * And back up one
			 */
      remove_arg(pos--, argc, argv);
    }
  }
  return(retval);
}