/*
   =============================================================================
	filname.c -- file name and extension extractors
	Version 3 -- 1987-07-09 -- D.N. Lynx Crowe
   =============================================================================
*/

#define	TESTER	0		/* define non-zero for test routine */

#include <stddefs.h>

#define	MAX_NAME	8	/* maximum length of a file name */
#define	MAX_EXT		3	/* maximum length of an extension */

/*
   =============================================================================
	FilName(s, p) -- Return a pointer to a string containing the file name
	found in the string at 's'.  Copy the file name into string 'p'.
   =============================================================================
*/

char *
FilName(s, p)
register char *s, *p;
{
	register char	*tp;
	register int i;

	tp = p;

	for (i = 0; i < MAX_NAME; i++) {	/* scan the name */

		if (*s) {			/* ... until we hit a '\0' */

			if (*s EQ '.')		/* ... or a '.' */
				break;

			*p++ = *s++;		/* ... copying as we go */

		} else {			/* stop at '\0' */

			*p = '\0';		/* terminate the string */
			return(tp);		/* return a pointer to it */
		}
	}

	*p = '\0';		/* copied MAX_NAME bytes - that's all folks */
	return(tp);
}

/* 
*/

/*
   =============================================================================
	FilExt(s, p) -- Returns a pointer to a copy of the extension of
	the file name in 's'.  The file name is copied into string 'p' and
	a pointer to 'p' is returned.
   =============================================================================
*/

char *
FilExt(s, p)
register char *s, *p;
{
	register char c, *tp;
	register int i;

	tp = p;

	while (c = *s) {		/* scan the string */

		if (c EQ '.') {		/* ... until we hit the dot */

			++s;		/* point past the dot */

			for (i = 0; i < MAX_EXT; i++) {	/* scan the extension ... */

				if (*s) {		/* ... until we hit a '\0' */

					*p++ = *s++;	/* ... copying as we go */

				} else {		/* stop at '\0' */

					*p = '\0';	/* terminate the string */
					return(tp);	/* return a pointer to it */
				}
			}

			*p = '\0';	/* copied MAX_EXT bytes - that's all folks */
			return(tp);	/* return a pointer to the result */
				
		} else {

			++s;		/* advance the pointer */
		}
	}

	*p = '\0';	/* terminate the string */
	return(tp);	/* return a pointer to the result */
}

/* 
*/

#if	TESTER

char	*fn[] = {		/* test cases */

	"FILE.NAM",
	"FILE",
	"FILE.",
	".NAM",
	".",
	"",
	"fartoolonganame.longextension",
	"fartoolonganame",
	"fartoolonganame.",
	".longextension"
};

#define	NCASES	((sizeof fn) / (sizeof (char *)))

char	temp1[MAX_NAME+1], temp2[MAX_EXT+1];

fnt(s)		/* test both functions and print the result */
char *s;
{
	printf("[%s] gave [%s] [%s]\r\n",
		s, FilName(s, temp1), FilExt(s, temp2));
}

main()
{
	int	i;

	/* hand the functions each of the test cases */

	for (i = 0; i < NCASES; i++)
		fnt(fn[i]);

	exit();
}

#endif