BSD 4_3_Net_2 release

[unix-history] / usr / src / usr.bin / window / context.c

/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Wang at The University of California, Berkeley.
 *
 * 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[] = "@(#)context.c	3.12 (Berkeley) 6/6/90";
#endif /* not lint */

#include "value.h"
#include "string.h"
#include "context.h"

/*
 * Context push/pop for nested command files.
 */

char *malloc();

cx_alloc()
{
	register struct context *xp;

	if (cx.x_type != 0) {
		xp = (struct context *)
			malloc((unsigned) sizeof (struct context));
		if (xp == 0)
			return -1;
		*xp = cx;
		cx.x_link = xp;
		cx.x_type = 0;
	}
	cx.x_erred = 0;
	cx.x_synerred = 0;
	cx.x_abort = 0;
	return 0;
}

cx_free()
{
	struct context *xp;

	if ((xp = cx.x_link) != 0) {
		cx = *xp;
		free((char *)xp);
	} else
		cx.x_type = 0;
}

cx_beginfile(filename)
char *filename;
{
	if (cx_alloc() < 0)
		return -1;
	cx.x_type = X_FILE;
	if ((cx.x_filename = str_cpy(filename)) == 0)
		goto bad;
	cx.x_fp = fopen(filename, "r");
	if (cx.x_fp == 0)
		goto bad;
	cx.x_bol = 1;
	cx.x_lineno = 0;
	cx.x_errwin = 0;
	cx.x_noerr = 0;
	return 0;
bad:
	if (cx.x_filename != 0)
		str_free(cx.x_filename);
	cx_free();
	return -1;
}

cx_beginbuf(buf, arg, narg)
char *buf;
struct value *arg;
int narg;
{
	if (cx_alloc() < 0)
		return -1;
	cx.x_type = X_BUF;
	cx.x_bufp = cx.x_buf = buf;
	cx.x_arg = arg;
	cx.x_narg = narg;
	return 0;
}

cx_end()
{
	switch (cx.x_type) {
	case X_BUF:
		break;
	case X_FILE:
		(void) fclose(cx.x_fp);
		str_free(cx.x_filename);
		break;
	}
	cx_free();
}