4.4BSD/usr/src/contrib/nvi/nvi/ex/ex_usage.c

/*-
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char sccsid[] = "@(#)ex_usage.c	8.1 (Berkeley) 6/9/93";
#endif /* not lint */

#include <sys/types.h>
#include <string.h>

#include "vi.h"
#include "excmd.h"
#include "vcmd.h"

/*
 * ex_usage -- :usage cmd
 *	Display ex usage strings.
 */
int
ex_usage(sp, ep, cmdp)
	SCR *sp;
	EXF *ep;
	EXCMDARG *cmdp;
{
	EXCMDLIST *cp;
	size_t len;
	char *p;
	
	for (cp = cmds, p = cmdp->argv[0], len = strlen(p);
	    cp->name && memcmp(p, cp->name, len); ++cp);
	if (cp->name == NULL) {
		msgq(sp, M_ERR, "The %.*s command is unknown.", len, p);
		return (1);
	}
	(void)fprintf(sp->stdfp, "Usage: %s", cp->usage);
	return (0);
}

/*
 * ex_viusage -- :viusage key
 *	Display vi usage strings.
 */
int
ex_viusage(sp, ep, cmdp)
	SCR *sp;
	EXF *ep;
	EXCMDARG *cmdp;
{
	VIKEYS const *kp;
	int key;

	key = *cmdp->argv[0];
	if (key > MAXVIKEY)
		goto nokey;

	kp = &vikeys[key];
	if (kp->func == NULL) {
nokey:		msgq(sp, M_ERR,
		    "The %s key has no current meaning", charname(sp, key));
		return (1);
	}

	(void)fprintf(sp->stdfp, "Usage: %s", kp->usage);
	return (0);
}