/****************************************************************************
 * miscutils.c                                                              *
 *                                                                          *
 * LocalGate Local Filesystem -> WWW Gateway                                *
 *                                                                          *
 * LocalGate allows a user to access HTML files on the local filesystem     *
 * as if they had a web server to access the files.                         *
 *                                                                          *
 * miscutils.c: miscellaneous routines for LocalGate.                       *
 *                                                                          *
 * Copyright (C) 1997  Michael Chu                                          *
 * This file is part of the LocalGate local filesystem -> WWW gateway.      *
 *                                                                          *
 * This program is free software; you can redistribute it and/or modify     *
 * it under the terms of the GNU General Public License as published by     *
 * the Free Software Foundation; either version 2 of the License, or        *
 * (at your option) any later version.                                      *
 *                                                                          *
 * This program is distributed in the hope that it will be useful,          *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of           *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            *
 * GNU General Public License for more details.                             *
 *                                                                          *
 * You should have received a copy of the GNU General Public License        *
 * along with this program; if not, write to the Free Software              *
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.                *
 *                                                                          *
 * Contact information:      Michael Chu                                    *
 *                           mmchu@pobox.com                                *
 ****************************************************************************/


/*********************************** INCLUDES *******************************/

#include <string.h>
#include <ctype.h>
#include <assert.h>
#include "miscutils.h"


/********************************** FUNCTIONS *******************************/

/****************************************************************************
 * isUnsignedInteger:                                                       *
 *                                                                          *
 * Summary: Returns whether string represents an unsigned integer.          *
 *                                                                          *
 * Input:   numberString: string to check.                                  *
 *                                                                          *
 * Returns: 0 (zero) if numberString does not represents an unsigned        *
 *            integer.                                                      *
 *          1 (one) if numberString represents an unsigned integer.         *
 *                                                                          *
 * Global State Affected:                                                   *
 *          None.                                                           *
 ****************************************************************************/
int isUnsignedInteger(char *numberString) {
  int stringLength = 0;               /* length of string. */
  int stringIndex = 0;                /* index of string. */

  /* make sure that numberString is not NULL. */
  assert(numberString != NULL);

  /* get the string length. */
  stringLength = strlen(numberString);

  /* if the length was zero, then it was not an unsigned integer. */
  if (stringLength == 0) {
    /* this is not an unsigned integer. */
    return(0);
  } 

  /* check all characters for digits. */
  for (stringIndex = 0; stringIndex < stringLength; stringIndex++) {
    if (!(isdigit(numberString[stringIndex]))) {
      /* this is not an unsigned integer. */
	return(0);
    }
  }

  /* if we got this far, then it is an unsigned integer. */
  return(1);
}