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 1.3 1999/10/11 12:59:21 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 #ifdef __linux__
  71 #include <linux/ext2_fs.h>
  72 #include <ext2fs/ext2fs.h>
  73 #include <bsdcompat.h>
  74 #endif
  75
  76 int     tape = -1;
  77
  78 char    *record;
  79 int     maxrecsize = -1;
  80
  81 #define SSIZE   64
  82 char    device[SSIZE];
  83 char    count[SSIZE], mode[SSIZE], pos[SSIZE], op[SSIZE];
  84
  85 char    resp[BUFSIZ];
  86
  87 FILE    *debug;
  88 #define DEBUG(f)        if (debug) fprintf(debug, f)
  89 #define DEBUG1(f,a)     if (debug) fprintf(debug, f, a)
  90 #define DEBUG2(f,a1,a2) if (debug) fprintf(debug, f, a1, a2)
  91
  92 char    *checkbuf __P((char *, int));
  93 void     error __P((int));
  94 void     getstring __P((char *));
  95
  96 int
  97 main(int argc, char *argv[])
  98 {
  99         int rval = 0;
 100         char c;
 101         int n, i, cc;
 102
 103         argc--, argv++;
 104         if (argc > 0) {
 105                 debug = fopen(*argv, "w");
 106                 if (debug == 0)
 107                         exit(1);
 108                 (void)setbuf(debug, (char *)0);
 109         }
 110 top:
 111         errno = 0;
 112         rval = 0;
 113         if (read(0, &c, 1) != 1)
 114                 exit(0);
 115         switch (c) {
 116
 117         case 'O':
 118                 if (tape >= 0)
 119                         (void) close(tape);
 120                 getstring(device);
 121                 getstring(mode);
 122                 DEBUG2("rmtd: O %s %s\n", device, mode);
 123                 /*
 124                  * XXX the rmt protocol does not provide a means to
 125                  * specify the permission bits; allow rw for everyone,
 126                  * as modified by the users umask
 127                  */
 128                 tape = open(device, atoi(mode), 0666);
 129                 if (tape < 0)
 130                         goto ioerror;
 131                 goto respond;
 132
 133         case 'C':
 134                 DEBUG("rmtd: C\n");
 135                 getstring(device);              /* discard */
 136                 if (close(tape) < 0)
 137                         goto ioerror;
 138                 tape = -1;
 139                 goto respond;
 140
 141         case 'L':
 142                 getstring(count);
 143                 getstring(pos);
 144                 DEBUG2("rmtd: L %s %s\n", count, pos);
 145                 rval = lseek(tape, (off_t)atol(count), atoi(pos));
 146                 if (rval < 0)
 147                         goto ioerror;
 148                 goto respond;
 149
 150         case 'W':
 151                 getstring(count);
 152                 n = atoi(count);
 153                 DEBUG1("rmtd: W %s\n", count);
 154                 record = checkbuf(record, n);
 155                 for (i = 0; i < n; i += cc) {
 156                         cc = read(0, &record[i], n - i);
 157                         if (cc <= 0) {
 158                                 DEBUG("rmtd: premature eof\n");
 159                                 exit(2);
 160                         }
 161                 }
 162                 rval = write(tape, record, n);
 163                 if (rval < 0)
 164                         goto ioerror;
 165                 goto respond;
 166
 167         case 'R':
 168                 getstring(count);
 169                 DEBUG1("rmtd: R %s\n", count);
 170                 n = atoi(count);
 171                 record = checkbuf(record, n);
 172                 rval = read(tape, record, n);
 173                 if (rval < 0)
 174                         goto ioerror;
 175                 (void)sprintf(resp, "A%d\n", rval);
 176                 (void)write(1, resp, strlen(resp));
 177                 (void)write(1, record, rval);
 178                 goto top;
 179
 180         case 'I':
 181                 getstring(op);
 182                 getstring(count);
 183                 DEBUG2("rmtd: I %s %s\n", op, count);
 184                 { struct mtop mtop;
 185                   mtop.mt_op = atoi(op);
 186                   mtop.mt_count = atoi(count);
 187                   if (ioctl(tape, MTIOCTOP, (char *)&mtop) < 0)
 188                         goto ioerror;
 189                   rval = mtop.mt_count;
 190                 }
 191                 goto respond;
 192
 193         case 'S':               /* status */
 194                 DEBUG("rmtd: S\n");
 195                 { struct mtget mtget;
 196                   if (ioctl(tape, MTIOCGET, (char *)&mtget) < 0)
 197                         goto ioerror;
 198                   rval = sizeof (mtget);
 199                   (void)sprintf(resp, "A%d\n", rval);
 200                   (void)write(1, resp, strlen(resp));
 201                   (void)write(1, (char *)&mtget, sizeof (mtget));
 202                   goto top;
 203                 }
 204
 205         case 'V':               /* version */
 206                 getstring(op);
 207                 DEBUG1("rmtd: V %s\n", op);
 208                 rval = 2;
 209                 goto respond;
 210
 211         default:
 212                 DEBUG1("rmtd: garbage command %c\n", c);
 213                 exit(3);
 214         }
 215 respond:
 216         DEBUG1("rmtd: A %d\n", rval);
 217         (void)sprintf(resp, "A%d\n", rval);
 218         (void)write(1, resp, strlen(resp));
 219         goto top;
 220 ioerror:
 221         error(errno);
 222         goto top;
 223 }
 224
 225 void getstring(char *bp)
 226 {
 227         int i;
 228         char *cp = bp;
 229
 230         for (i = 0; i < SSIZE; i++) {
 231                 if (read(0, cp+i, 1) != 1)
 232                         exit(0);
 233                 if (cp[i] == '\n')
 234                         break;
 235         }
 236         cp[i] = '\0';
 237 }
 238
 239 char *
 240 checkbuf(char *record, 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(int num)
 261 {
 262
 263         DEBUG2("rmtd: E %d (%s)\n", num, strerror(num));
 264         (void)snprintf(resp, sizeof(resp), "E%d\n%s\n", num, strerror(num));
 265         (void)write(1, resp, strlen(resp));
 266 }