1/*	$NetBSD: rmt.c,v 1.17 2018/01/23 21:06:25 sevan Exp $	*/
2
3/*
4 * Copyright (c) 1983, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#ifndef lint
34__COPYRIGHT("@(#) Copyright (c) 1983, 1993\
35 The Regents of the University of California.  All rights reserved.");
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)rmt.c	8.1 (Berkeley) 6/6/93";
41#else
42__RCSID("$NetBSD: rmt.c,v 1.17 2018/01/23 21:06:25 sevan Exp $");
43#endif
44#endif /* not lint */
45
46/*
47 * rmt
48 */
49#include <sys/types.h>
50#include <sys/ioctl.h>
51#include <sys/mtio.h>
52#include <sys/socket.h>
53#include <sys/stat.h>
54
55#include <errno.h>
56#include <fcntl.h>
57#include <stdio.h>
58#include <stdlib.h>
59#include <string.h>
60#include <unistd.h>
61
62int	tape = -1;
63
64int	maxrecsize = -1;
65
66#define	SSIZE	64
67char	device[SSIZE];
68char	count[SSIZE], mode[SSIZE], pos[SSIZE], op[SSIZE];
69
70char	resp[BUFSIZ];
71
72FILE	*debug;
73#define	DEBUG(f)	if (debug) fprintf(debug, f)
74#define	DEBUG1(f,a)	if (debug) fprintf(debug, f, a)
75#define	DEBUG2(f,a1,a2)	if (debug) fprintf(debug, f, a1, a2)
76
77char	*checkbuf(char *, int);
78void	 error(int);
79void	 getstring(char *, size_t);
80
81int
82main(int argc, char *argv[])
83{
84	char *record = NULL;
85	int rval;
86	char c;
87	int n, i, cc;
88
89	argc--, argv++;
90	if (argc > 0) {
91		debug = fopen(*argv, "w");
92		if (debug == 0)
93			exit(1);
94		(void)setbuf(debug, (char *)0);
95	}
96top:
97	errno = 0;
98	rval = 0;
99	if (read(STDIN_FILENO, &c, 1) != 1)
100		exit(0);
101	switch (c) {
102
103	case 'O':
104		if (tape >= 0)
105			(void) close(tape);
106		getstring(device, sizeof(device));
107		getstring(mode, sizeof(mode));
108		DEBUG2("rmtd: O %s %s\n", device, mode);
109		tape = open(device, atoi(mode),
110		    S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH);
111		if (tape < 0)
112			goto ioerror;
113		goto respond;
114
115	case 'C':
116		DEBUG("rmtd: C\n");
117		getstring(device, sizeof(device));	/* discard */
118		if (close(tape) < 0)
119			goto ioerror;
120		tape = -1;
121		goto respond;
122
123	case 'L':
124		getstring(count, sizeof(count));
125		getstring(pos, sizeof(pos));
126		DEBUG2("rmtd: L %s %s\n", count, pos);
127		rval = lseek(tape, (off_t)strtoll(count, NULL, 10), atoi(pos));
128		if (rval < 0)
129			goto ioerror;
130		goto respond;
131
132	case 'W':
133		getstring(count, sizeof(count));
134		n = atoi(count);
135		DEBUG1("rmtd: W %s\n", count);
136		record = checkbuf(record, n);
137		for (i = 0; i < n; i += cc) {
138			cc = read(STDIN_FILENO, &record[i], n - i);
139			if (cc <= 0) {
140				DEBUG("rmtd: premature eof\n");
141				exit(2);
142			}
143		}
144		rval = write(tape, record, n);
145		if (rval < 0)
146			goto ioerror;
147		goto respond;
148
149	case 'R':
150		getstring(count, sizeof(count));
151		DEBUG1("rmtd: R %s\n", count);
152		n = atoi(count);
153		record = checkbuf(record, n);
154		rval = read(tape, record, n);
155		if (rval < 0)
156			goto ioerror;
157		(void)snprintf(resp, sizeof(resp), "A%d\n", rval);
158		(void)write(STDOUT_FILENO, resp, strlen(resp));
159		(void)write(STDOUT_FILENO, record, rval);
160		goto top;
161
162	case 'I':
163		getstring(op, sizeof(op));
164		getstring(count, sizeof(count));
165		DEBUG2("rmtd: I %s %s\n", op, count);
166		{
167			struct mtop mtop;
168
169			mtop.mt_op = atoi(op);
170			mtop.mt_count = atoi(count);
171			if (ioctl(tape, MTIOCTOP, (char *)&mtop) < 0)
172				goto ioerror;
173			rval = mtop.mt_count;
174		}
175		goto respond;
176
177	case 'S':		/* status */
178		DEBUG("rmtd: S\n");
179		{
180			struct mtget mtget;
181
182			if (ioctl(tape, MTIOCGET, (char *)&mtget) < 0)
183				goto ioerror;
184			rval = sizeof (mtget);
185			/* limit size to 'original' mtget size */
186			if (rval > 24)
187				rval = 24;
188			(void)snprintf(resp, sizeof(resp), "A%d\n", rval);
189			(void)write(STDOUT_FILENO, resp, strlen(resp));
190			(void)write(STDOUT_FILENO, (char *)&mtget, rval);
191			goto top;
192		}
193
194	default:
195		DEBUG1("rmtd: garbage command %c\n", c);
196		exit(3);
197	}
198respond:
199	DEBUG1("rmtd: A %d\n", rval);
200	(void)snprintf(resp, sizeof(resp), "A%d\n", rval);
201	(void)write(STDOUT_FILENO, resp, strlen(resp));
202	goto top;
203ioerror:
204	error(errno);
205	goto top;
206}
207
208void
209getstring(char *bp, size_t size)
210{
211	char *cp = bp;
212	char *ep = bp + size - 1;
213
214	do {
215		if (read(STDIN_FILENO, cp, 1) != 1)
216			exit(0);
217	} while (*cp != '\n' && ++cp < ep);
218	*cp = '\0';
219}
220
221char *
222checkbuf(char *record, int size)
223{
224
225	if (size <= maxrecsize)
226		return (record);
227	if (record != 0)
228		free(record);
229	record = malloc(size);
230	if (record == 0) {
231		DEBUG("rmtd: cannot allocate buffer space\n");
232		exit(4);
233	}
234	maxrecsize = size;
235	while (size > 1024 &&
236	    setsockopt(0, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size)) < 0)
237		size -= 1024;
238	return (record);
239}
240
241void
242error(int num)
243{
244
245	DEBUG2("rmtd: E %d (%s)\n", num, strerror(num));
246	(void)snprintf(resp, sizeof(resp), "E%d\n%s\n", num, strerror(num));
247	(void)write(STDOUT_FILENO, resp, strlen(resp));
248}
249