rmt/rmt.c

   1 /*
   2  *      Ported to Linux's Second Extended File System as part of the
   3  *      dump and restore backup suit
   4  *      Remy Card <card@Linux.EU.Org>, 1994-1997
   5  *      Stelian Pop <pop@cybercable.fr>, 1999
   6  *
   7  */
   8
   9 /*
  10  * Copyright (c) 1983, 1993
  11  *      The Regents of the University of California.  All rights reserved.
  12  *
  13  * Redistribution and use in source and binary forms, with or without
  14  * modification, are permitted provided that the following conditions
  15  * are met:
  16  * 1. Redistributions of source code must retain the above copyright
  17  *    notice, this list of conditions and the following disclaimer.
  18  * 2. Redistributions in binary form must reproduce the above copyright
  19  *    notice, this list of conditions and the following disclaimer in the
  20  *    documentation and/or other materials provided with the distribution.
  21  * 3. All advertising materials mentioning features or use of this software
  22  *    must display the following acknowledgement:
  23  *      This product includes software developed by the University of
  24  *      California, Berkeley and its contributors.
  25  * 4. Neither the name of the University nor the names of its contributors
  26  *    may be used to endorse or promote products derived from this software
  27  *    without specific prior written permission.
  28  *
  29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  39  * SUCH DAMAGE.
  40  */
  41
  42 #ifndef lint
  43 static const char copyright[] =
  44 "@(#) Copyright (c) 1983, 1993\n\
  45         The Regents of the University of California.  All rights reserved.\n";
  46 #endif /* not lint */
  47
  48 #ifndef lint
  49 #if 0
  50 static char sccsid[] = "@(#)rmt.c       8.1 (Berkeley) 6/6/93";
  51 #endif
  52 static const char rcsid[] =
  53         "$Id: rmt.c,v 1.2 1999/10/11 12:53:25 stelian Exp $";
  54 #endif /* not lint */
  55
  56 /*
  57  * rmt
  58  */
  59 #include <sys/types.h>
  60 #include <sys/socket.h>
  61 #include <sys/mtio.h>
  62 #include <errno.h>
  63 #include <fcntl.h>
  64 #include <sgtty.h>
  65 #include <stdio.h>
  66 #include <stdlib.h>
  67 #include <string.h>
  68 #include <unistd.h>
  69
  70 int     tape = -1;
  71
  72 char    *record;
  73 int     maxrecsize = -1;
  74
  75 #define SSIZE   64
  76 char    device[SSIZE];
  77 char    count[SSIZE], mode[SSIZE], pos[SSIZE], op[SSIZE];
  78
  79 char    resp[BUFSIZ];
  80
  81 FILE    *debug;
  82 #define DEBUG(f)        if (debug) fprintf(debug, f)
  83 #define DEBUG1(f,a)     if (debug) fprintf(debug, f, a)
  84 #define DEBUG2(f,a1,a2) if (debug) fprintf(debug, f, a1, a2)
  85
  86 char    *checkbuf __P((char *, int));
  87 void     error __P((int));
  88 void     getstring __P((char *));
  89
  90 int
  91 main(argc, argv)
  92         int argc;
  93         char **argv;
  94 {
  95         int rval;
  96         char c;
  97         int n, i, cc;
  98
  99         argc--, argv++;
 100         if (argc > 0) {
 101                 debug = fopen(*argv, "w");
 102                 if (debug == 0)
 103                         exit(1);
 104                 (void)setbuf(debug, (char *)0);
 105         }
 106 top:
 107         errno = 0;
 108         rval = 0;
 109         if (read(0, &c, 1) != 1)
 110                 exit(0);
 111         switch (c) {
 112
 113         case 'O':
 114                 if (tape >= 0)
 115                         (void) close(tape);
 116                 getstring(device);
 117                 getstring(mode);
 118                 DEBUG2("rmtd: O %s %s\n", device, mode);
 119                 /*
 120                  * XXX the rmt protocol does not provide a means to
 121                  * specify the permission bits; allow rw for everyone,
 122                  * as modified by the users umask
 123                  */
 124                 tape = open(device, atoi(mode), 0666);
 125                 if (tape < 0)
 126                         goto ioerror;
 127                 goto respond;
 128
 129         case 'C':
 130                 DEBUG("rmtd: C\n");
 131                 getstring(device);              /* discard */
 132                 if (close(tape) < 0)
 133                         goto ioerror;
 134                 tape = -1;
 135                 goto respond;
 136
 137         case 'L':
 138                 getstring(count);
 139                 getstring(pos);
 140                 DEBUG2("rmtd: L %s %s\n", count, pos);
 141                 rval = lseek(tape, (off_t)atol(count), atoi(pos));
 142                 if (rval < 0)
 143                         goto ioerror;
 144                 goto respond;
 145
 146         case 'W':
 147                 getstring(count);
 148                 n = atoi(count);
 149                 DEBUG1("rmtd: W %s\n", count);
 150                 record = checkbuf(record, n);
 151                 for (i = 0; i < n; i += cc) {
 152                         cc = read(0, &record[i], n - i);
 153                         if (cc <= 0) {
 154                                 DEBUG("rmtd: premature eof\n");
 155                                 exit(2);
 156                         }
 157                 }
 158                 rval = write(tape, record, n);
 159                 if (rval < 0)
 160                         goto ioerror;
 161                 goto respond;
 162
 163         case 'R':
 164                 getstring(count);
 165                 DEBUG1("rmtd: R %s\n", count);
 166                 n = atoi(count);
 167                 record = checkbuf(record, n);
 168                 rval = read(tape, record, n);
 169                 if (rval < 0)
 170                         goto ioerror;
 171                 (void)sprintf(resp, "A%d\n", rval);
 172                 (void)write(1, resp, strlen(resp));
 173                 (void)write(1, record, rval);
 174                 goto top;
 175
 176         case 'I':
 177                 getstring(op);
 178                 getstring(count);
 179                 DEBUG2("rmtd: I %s %s\n", op, count);
 180                 { struct mtop mtop;
 181                   mtop.mt_op = atoi(op);
 182                   mtop.mt_count = atoi(count);
 183                   if (ioctl(tape, MTIOCTOP, (char *)&mtop) < 0)
 184                         goto ioerror;
 185                   rval = mtop.mt_count;
 186                 }
 187                 goto respond;
 188
 189         case 'S':               /* status */
 190                 DEBUG("rmtd: S\n");
 191                 { struct mtget mtget;
 192                   if (ioctl(tape, MTIOCGET, (char *)&mtget) < 0)
 193                         goto ioerror;
 194                   rval = sizeof (mtget);
 195                   (void)sprintf(resp, "A%d\n", rval);
 196                   (void)write(1, resp, strlen(resp));
 197                   (void)write(1, (char *)&mtget, sizeof (mtget));
 198                   goto top;
 199                 }
 200
 201         case 'V':               /* version */
 202                 getstring(op);
 203                 DEBUG1("rmtd: V %s\n", op);
 204                 rval = 2;
 205                 goto respond;
 206
 207         default:
 208                 DEBUG1("rmtd: garbage command %c\n", c);
 209                 exit(3);
 210         }
 211 respond:
 212         DEBUG1("rmtd: A %d\n", rval);
 213         (void)sprintf(resp, "A%d\n", rval);
 214         (void)write(1, resp, strlen(resp));
 215         goto top;
 216 ioerror:
 217         error(errno);
 218         goto top;
 219 }
 220
 221 void
 222 getstring(bp)
 223         char *bp;
 224 {
 225         int i;
 226         char *cp = bp;
 227
 228         for (i = 0; i < SSIZE; i++) {
 229                 if (read(0, cp+i, 1) != 1)
 230                         exit(0);
 231                 if (cp[i] == '\n')
 232                         break;
 233         }
 234         cp[i] = '\0';
 235 }
 236
 237 char *
 238 checkbuf(record, size)
 239         char *record;
 240         int size;
 241 {
 242
 243         if (size <= maxrecsize)
 244                 return (record);
 245         if (record != 0)
 246                 free(record);
 247         record = malloc(size);
 248         if (record == 0) {
 249                 DEBUG("rmtd: cannot allocate buffer space\n");
 250                 exit(4);
 251         }
 252         maxrecsize = size;
 253         while (size > 1024 &&
 254                setsockopt(0, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size)) < 0)
 255                 size -= 1024;
 256         return (record);
 257 }
 258
 259 void
 260 error(num)
 261         int num;
 262 {
 263
 264         DEBUG2("rmtd: E %d (%s)\n", num, strerror(num));
 265         (void)snprintf(resp, sizeof(resp), "E%d\n%s\n", num, strerror(num));
 266         (void)write(1, resp, strlen(resp));
 267 }