tty_subs.c revision 330897 
1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1992 Keith Muller.
5 * Copyright (c) 1992, 1993
6 *	The Regents of the University of California.  All rights reserved.
7 *
8 * This code is derived from software contributed to Berkeley by
9 * Keith Muller of the University of California, San Diego.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#ifndef lint
37#if 0
38static char sccsid[] = "@(#)tty_subs.c	8.2 (Berkeley) 4/18/94";
39#endif
40#endif /* not lint */
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD: stable/11/bin/pax/tty_subs.c 330897 2018-03-14 03:19:51Z eadler $");
43
44#include <sys/types.h>
45#include <sys/stat.h>
46#include <fcntl.h>
47#include <stdio.h>
48#include <unistd.h>
49#include <string.h>
50#include "pax.h"
51#include "extern.h"
52#include <stdarg.h>
53
54/*
55 * routines that deal with I/O to and from the user
56 */
57
58#define DEVTTY	  "/dev/tty"      /* device for interactive i/o */
59static FILE *ttyoutf = NULL;		/* output pointing at control tty */
60static FILE *ttyinf = NULL;		/* input pointing at control tty */
61
62/*
63 * tty_init()
64 *	try to open the controlling terminal (if any) for this process. if the
65 *	open fails, future ops that require user input will get an EOF
66 */
67
68int
69tty_init(void)
70{
71	int ttyfd;
72
73	if ((ttyfd = open(DEVTTY, O_RDWR)) >= 0) {
74		if ((ttyoutf = fdopen(ttyfd, "w")) != NULL) {
75			if ((ttyinf = fdopen(ttyfd, "r")) != NULL)
76				return(0);
77			(void)fclose(ttyoutf);
78		}
79		(void)close(ttyfd);
80	}
81
82	if (iflag) {
83		paxwarn(1, "Fatal error, cannot open %s", DEVTTY);
84		return(-1);
85	}
86	return(0);
87}
88
89/*
90 * tty_prnt()
91 *	print a message using the specified format to the controlling tty
92 *	if there is no controlling terminal, just return.
93 */
94
95void
96tty_prnt(const char *fmt, ...)
97{
98	va_list ap;
99	if (ttyoutf == NULL)
100		return;
101	va_start(ap, fmt);
102	(void)vfprintf(ttyoutf, fmt, ap);
103	va_end(ap);
104	(void)fflush(ttyoutf);
105}
106
107/*
108 * tty_read()
109 *	read a string from the controlling terminal if it is open into the
110 *	supplied buffer
111 * Return:
112 *	0 if data was read, -1 otherwise.
113 */
114
115int
116tty_read(char *str, int len)
117{
118	char *pt;
119
120	if ((--len <= 0) || (ttyinf == NULL) || (fgets(str,len,ttyinf) == NULL))
121		return(-1);
122	*(str + len) = '\0';
123
124	/*
125	 * strip off that trailing newline
126	 */
127	if ((pt = strchr(str, '\n')) != NULL)
128		*pt = '\0';
129	return(0);
130}
131
132/*
133 * paxwarn()
134 *	write a warning message to stderr. if "set" the exit value of pax
135 *	will be non-zero.
136 */
137
138void
139paxwarn(int set, const char *fmt, ...)
140{
141	va_list ap;
142	va_start(ap, fmt);
143	if (set)
144		exit_val = 1;
145	/*
146	 * when vflag we better ship out an extra \n to get this message on a
147	 * line by itself
148	 */
149	if (vflag && vfpart) {
150		(void)fflush(listf);
151		(void)fputc('\n', stderr);
152		vfpart = 0;
153	}
154	(void)fprintf(stderr, "%s: ", argv0);
155	(void)vfprintf(stderr, fmt, ap);
156	va_end(ap);
157	(void)fputc('\n', stderr);
158}
159
160/*
161 * syswarn()
162 *	write a warning message to stderr. if "set" the exit value of pax
163 *	will be non-zero.
164 */
165
166void
167syswarn(int set, int errnum, const char *fmt, ...)
168{
169	va_list ap;
170	va_start(ap, fmt);
171	if (set)
172		exit_val = 1;
173	/*
174	 * when vflag we better ship out an extra \n to get this message on a
175	 * line by itself
176	 */
177	if (vflag && vfpart) {
178		(void)fflush(listf);
179		(void)fputc('\n', stderr);
180		vfpart = 0;
181	}
182	(void)fprintf(stderr, "%s: ", argv0);
183	(void)vfprintf(stderr, fmt, ap);
184	va_end(ap);
185
186	/*
187	 * format and print the errno
188	 */
189	if (errnum > 0)
190		(void)fprintf(stderr, " <%s>", strerror(errnum));
191	(void)fputc('\n', stderr);
192}
193