cmdline.c

/*
 * Name:    cmdline.c
 * Author:  Pietro Belotti
 * Purpose: procedures for reading/managing command line arguments
 *
 * This code is published under the Eclipse Public License (EPL).
 * See http://www.eclipse.org/legal/epl-v10.html
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "cmdline.h"

#define MALLOC_BLOCK 20

/*
 * Action to be taken for each parameter
 */

int act (char ***argv, int *argc, enum etype tact, void *par) {

  switch (tact) {

  case TTOGGLE:                              *(char   *) par = 1;                  break; /**< Toggle some parameter */
  case TCHARA:  if (!(--(*argc))) return -1; *(char   *) par  =        **++*argv;  break; /**< Char param */
  case TINT:    if (!(--(*argc))) return -1; *(int    *) par  = atoi   (*++*argv); break; /**< Integer param */
  case TDOUBLE: if (!(--(*argc))) return -1; *(double *) par  = atof   (*++*argv); break; /**< Double param */
  case TSTRING: if (!(--(*argc))) return -1; 
                *(char **) par = (char *) realloc (*(char **) par, (1 + strlen (*++*argv)) * sizeof (char));
		Strcpy (* (char **) par, strlen (**argv) + 1, **argv); break; /**< String param */

  default: printf ("switch{} mismatch in act ()\n"); return -1;
  }

  return 0;
}


/*
 * Set default value of the command line arguments
 */

void set_default_args (tpar *options) {

  for (; options -> shortopt; options++) 

    switch (options -> type) {

    case TINT:    * (int    *) (options -> par) = (int)    options -> initial; break;
    case TTOGGLE: * (char   *) (options -> par) = (char)   options -> initial; break;
    case TCHARA:  * (char   *) (options -> par) = (char)   options -> initial; break;
    case TDOUBLE: * (double *) (options -> par) = (double) options -> initial; break;
    case TSTRING: Strcpy (*(char **) options -> par, 1, ""); break;
    default: ;
    }
}


/*
 * Read argument line
 */ 

char **readargs (int argc, char **argv, tpar *options) {

  char **filenames = NULL;

  char *cumul;
  char *pname = *argv;

  int nfiles = 0;
  tpar *p2;

  /*
   * parse arguments, set corresponding parameters
   */

  while (--argc) {

    ++argv;

    if ((options) && 
	(** argv == '-') &&    /* arg starts with a "-"                               */
	((*argv) [1])) {       /* not a single "-" (meaning I should read from stdin) */

      cumul = *argv + 1;

      if (*cumul == '-') {  /** long option  ("--something [val]") */

	cumul++;

	for (p2 = options; p2 -> shortopt; p2++) {

	  if (!strcmp (cumul, p2->longopt)) {

	    if (!(p2 -> par)) {

	      if (p2 -> type != TTOGGLE) argv++;		  
	      printf ("%s: not yet implemented\n", *argv);
	    } 

	    else 

	      if (act (&argv, &argc, p2->type, (p2->par))) {

		printf ("%s: missing value\n", *(argv)); 
		return NULL;
	      }

	    break;
	  }
	}
	if (!(p2 -> shortopt)) {

	  printf ("%s: unrecognized option \"--%s\"\n", pname, cumul); 
	}
      }
      else {                   /** short option ("-s [val]") */

	for (; *cumul; cumul++) {

	  for (p2 = options; p2 -> shortopt; p2++)

	    if (*cumul == p2->shortopt) { 

	      if (act (&argv, &argc, p2->type, (p2->par))) {
		printf ("%s: missing value\n", *(argv)); 
		return NULL;
	      }
	      break;
	    }

	  if (!(p2 -> shortopt)) {

	    printf ("%s: unrecognized option \"-%c\"\n", pname, *cumul); 
	  }
	}
      }
    }
    else {

      if (!(nfiles % MALLOC_BLOCK)) {
	filenames = (char **) realloc (filenames, (nfiles + MALLOC_BLOCK) * sizeof (char *));
	filenames [0] = NULL;
      }

      filenames [nfiles] = (char *) malloc ((strlen (*argv) + 1) * sizeof (char));

      Strcpy (filenames [nfiles++], 1 + strlen (*argv), *argv);
    }
  }

  if (filenames) {

    if (!(nfiles % MALLOC_BLOCK)) 
      filenames = (char **) realloc (filenames, (nfiles + 1) * sizeof (char *));

    filenames [nfiles] = NULL;
  }

  return filenames;
}


/*
 * Print help message
 */

void print_help (char *pname, tpar *opt) {

  int i;

  char arg [5];
  char helpline [80];

  printf ("Usage: %s [options] file...\nOptions are:\n", pname);

  for (i=0; opt [i]. shortopt; i++) {

    switch (opt [i]. type) {
    case TTOGGLE: *arg=0;                break; /*Sprintf (arg, "    "); break;*/
    case TCHARA:  Sprintf (arg, " <c>"); break;
    case TSTRING: Sprintf (arg, " <s>"); break;
    case TDOUBLE: Sprintf (arg, " <x>"); break;
    case TINT:    Sprintf (arg, " <n>"); break;
    }

    Sprintf (helpline,"  -%c%s, --%s%s:", opt [i].shortopt, arg,
	    opt [i].longopt,  arg);

    printf ("%-40s %s\n", helpline, opt [i].help);
  }
}