/*
**  @(#)getopt.c    2.2 (smail) 1/26/87
*/
  
/*
 * Here's something you've all been waiting for:  the AT&T public domain
 * source for getopt(3).  It is the code which was given out at the 1985
 * UNIFORUM conference in Dallas.  I obtained it by electronic mail
 * directly from AT&T.  The people there assure me that it is indeed
 * in the public domain.
 *
 * There is no manual page.  That is because the one they gave out at
 * UNIFORUM was slightly different from the current System V Release 2
 * manual page.  The difference apparently involved a note about the
 * famous rules 5 and 6, recommending using white space between an option
 * and its first argument, and not grouping options that have arguments.
 * Getopt itself is currently lenient about both of these things White
 * space is allowed, but not mandatory, and the last option in a group can
 * have an argument.  That particular version of the man page evidently
 * has no official existence, and my source at AT&T did not send a copy.
 * The current SVR2 man page reflects the actual behavor of this getopt.
 * However, I am not about to post a copy of anything licensed by AT&T.
 */
  
#include "global.h"
#define index strchr
#ifdef BSD
#include <strings.h>
#endif
  
#ifdef  __TURBOC__
#include <io.h>     /* added by KA9Q for Turbo-C */
#endif
#ifdef  AMIGA
#include <fcntl.h>
#endif
  
/*LINTLIBRARY*/
#ifndef NULL
#define NULL    0
#endif
#define EOF (-1)
#ifdef LINUX
extern int write __ARGS((int,void*,unsigned));
#endif
#define ERR(s, c)   if(opterr){\
char errbuf[2];\
errbuf[0] = c; errbuf[1] = '\n';\
(void) write(2, argv[0], (unsigned)strlen(argv[0]));\
(void) write(2, s, (unsigned)strlen(s));\
(void) write(2, errbuf, 2);}
  
int opterr = 1;
int optind = 1;
int optopt;
char    *optarg;
  
int
getopt(argc, argv, opts)
int argc;
char    **argv, *opts;
{
    static int sp = 1;
    register int c;
    register char *cp;
  
    if(sp == 1)
        if(optind >= argc ||
            argv[optind][0] != '-' || argv[optind][1] == '\0')
            return(EOF);
        else if(strcmp(argv[optind], "--") == 0) {
            optind++;
            return(EOF);
        }
    optopt = c = argv[optind][sp];
    if(c == ':' || (cp=index(opts, c)) == NULL) {
        ERR(": illegal option -- ", c);
        if(argv[optind][++sp] == '\0') {
            optind++;
            sp = 1;
        }
        return('?');
    }
    if(*++cp == ':') {
        if(argv[optind][sp+1] != '\0')
            optarg = &argv[optind++][sp+1];
        else if(++optind >= argc) {
            ERR(": option requires an argument -- ", c);
            sp = 1;
            return('?');
        } else
            optarg = argv[optind++];
        sp = 1;
    } else {
        if(argv[optind][++sp] == '\0') {
            sp = 1;
            optind++;
        }
        optarg = NULL;
    }
    return(c);
}
