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  * Copyright (c) 1983, 1993
  10  *      The Regents of the University of California.  All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions and the following disclaimer.
  17  * 2. Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in the
  19  *    documentation and/or other materials provided with the distribution.
  20  * 3. All advertising materials mentioning features or use of this software
  21  *    must display the following acknowledgement:
  22  *      This product includes software developed by the University of
  23  *      California, Berkeley and its contributors.
  24  * 4. Neither the name of the University nor the names of its contributors
  25  *    may be used to endorse or promote products derived from this software
  26  *    without specific prior written permission.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  38  * SUCH DAMAGE.
  39  */
  40
  41 #ifndef lint
  42 static const char rcsid[] =
  43         "$Id: rmt.c,v 1.7 1999/11/11 16:14:01 tiniou Exp $";
  44 #endif /* not linux */
  45
  46 /*
  47  * rmt
  48  */
  49 #include <sys/types.h>
  50 #include <sys/socket.h>
  51 #include <sys/mtio.h>
  52 #include <errno.h>
  53 #include <fcntl.h>
  54 #ifndef __linux__
  55 #include <sgtty.h>
  56 #endif
  57 #include <stdio.h>
  58 #include <stdlib.h>
  59 #include <string.h>
  60 #include <unistd.h>
  61
  62 #ifdef __linux__
  63 #include <linux/ext2_fs.h>
  64 #include <ext2fs/ext2fs.h>
  65 #include <bsdcompat.h>
  66 #endif
  67
  68 int     tape = -1;
  69
  70 char    *record;
  71 int     maxrecsize = -1;
  72
  73 #define SSIZE   64
  74 char    device[SSIZE];
  75 char    count[SSIZE], filemode[SSIZE], pos[SSIZE], op[SSIZE];
  76
  77 char    resp[BUFSIZ];
  78
  79 FILE    *debug;
  80 #define DEBUG(f)        if (debug) fprintf(debug, f)
  81 #define DEBUG1(f,a)     if (debug) fprintf(debug, f, a)
  82 #define DEBUG2(f,a1,a2) if (debug) fprintf(debug, f, a1, a2)
  83
  84 char    *checkbuf __P((char *, int));
  85 void     error __P((int));
  86 void     getstring __P((char *));
  87
  88 int
  89 main(int argc, char *argv[])
  90 {
  91         int rval = 0;
  92         char c;
  93         int n, i, cc;
  94
  95         argc--, argv++;
  96         if (argc > 0) {
  97                 debug = fopen(*argv, "w");
  98                 if (debug == 0)
  99                         exit(1);
 100                 (void)setbuf(debug, (char *)0);
 101         }
 102 top:
 103         errno = 0;
 104         rval = 0;
 105         if (read(0, &c, 1) != 1)
 106                 exit(0);
 107         switch (c) {
 108
 109         case 'O':
 110                 if (tape >= 0)
 111                         (void) close(tape);
 112                 getstring(device);
 113                 getstring(filemode);
 114                 DEBUG2("rmtd: O %s %s\n", device, filemode);
 115                 /*
 116                  * XXX the rmt protocol does not provide a means to
 117                  * specify the permission bits; allow rw for everyone,
 118                  * as modified by the users umask
 119                  */
 120                 tape = open(device, atoi(filemode), 0666);
 121                 if (tape < 0)
 122                         goto ioerror;
 123                 goto respond;
 124
 125         case 'C':
 126                 DEBUG("rmtd: C\n");
 127                 getstring(device);              /* discard */
 128                 if (close(tape) < 0)
 129                         goto ioerror;
 130                 tape = -1;
 131                 goto respond;
 132
 133         case 'L':
 134                 getstring(count);
 135                 getstring(pos);
 136                 DEBUG2("rmtd: L %s %s\n", count, pos);
 137                 rval = lseek(tape, (off_t)atol(count), atoi(pos));
 138                 if (rval < 0)
 139                         goto ioerror;
 140                 goto respond;
 141
 142         case 'W':
 143                 getstring(count);
 144                 n = atoi(count);
 145                 DEBUG1("rmtd: W %s\n", count);
 146                 record = checkbuf(record, n);
 147                 for (i = 0; i < n; i += cc) {
 148                         cc = read(0, &record[i], n - i);
 149                         if (cc <= 0) {
 150                                 DEBUG("rmtd: premature eof\n");
 151                                 exit(2);
 152                         }
 153                 }
 154                 rval = write(tape, record, n);
 155                 if (rval < 0)
 156                         goto ioerror;
 157                 goto respond;
 158
 159         case 'R':
 160                 getstring(count);
 161                 DEBUG1("rmtd: R %s\n", count);
 162                 n = atoi(count);
 163                 record = checkbuf(record, n);
 164                 rval = read(tape, record, n);
 165                 if (rval < 0)
 166                         goto ioerror;
 167                 (void)sprintf(resp, "A%d\n", rval);
 168                 (void)write(1, resp, strlen(resp));
 169                 (void)write(1, record, rval);
 170                 goto top;
 171
 172         case 'I':
 173                 getstring(op);
 174                 getstring(count);
 175                 DEBUG2("rmtd: I %s %s\n", op, count);
 176                 { struct mtop mtop;
 177                   mtop.mt_op = atoi(op);
 178                   mtop.mt_count = atoi(count);
 179                   if (ioctl(tape, MTIOCTOP, (char *)&mtop) < 0)
 180                         goto ioerror;
 181                   rval = mtop.mt_count;
 182                 }
 183                 goto respond;
 184
 185         case 'S':               /* status */
 186                 DEBUG("rmtd: S\n");
 187                 { struct mtget mtget;
 188                   if (ioctl(tape, MTIOCGET, (char *)&mtget) < 0)
 189                         goto ioerror;
 190                   rval = sizeof (mtget);
 191                   (void)sprintf(resp, "A%d\n", rval);
 192                   (void)write(1, resp, strlen(resp));
 193                   (void)write(1, (char *)&mtget, sizeof (mtget));
 194                   goto top;
 195                 }
 196
 197         case 'V':               /* version */
 198                 getstring(op);
 199                 DEBUG1("rmtd: V %s\n", op);
 200                 rval = 2;
 201                 goto respond;
 202
 203         default:
 204                 DEBUG1("rmtd: garbage command %c\n", c);
 205                 exit(3);
 206         }
 207 respond:
 208         DEBUG1("rmtd: A %d\n", rval);
 209         (void)sprintf(resp, "A%d\n", rval);
 210         (void)write(1, resp, strlen(resp));
 211         goto top;
 212 ioerror:
 213         error(errno);
 214         goto top;
 215 }
 216
 217 void getstring(char *bp)
 218 {
 219         int i;
 220         char *cp = bp;
 221
 222         for (i = 0; i < SSIZE; i++) {
 223                 if (read(0, cp+i, 1) != 1)
 224                         exit(0);
 225                 if (cp[i] == '\n')
 226                         break;
 227         }
 228         cp[i] = '\0';
 229 }
 230
 231 char *
 232 checkbuf(char *record, int size)
 233 {
 234
 235         if (size <= maxrecsize)
 236                 return (record);
 237         if (record != 0)
 238                 free(record);
 239         record = malloc(size);
 240         if (record == 0) {
 241                 DEBUG("rmtd: cannot allocate buffer space\n");
 242                 exit(4);
 243         }
 244         maxrecsize = size;
 245         while (size > 1024 &&
 246                setsockopt(0, SOL_SOCKET, SO_RCVBUF, &size, sizeof (size)) < 0)
 247                 size -= 1024;
 248         return (record);
 249 }
 250
 251 void
 252 error(int num)
 253 {
 254
 255         DEBUG2("rmtd: E %d (%s)\n", num, strerror(num));
 256         (void)snprintf(resp, sizeof(resp), "E%d\n%s\n", num, strerror(num));
 257         (void)write(1, resp, strlen(resp));
 258 }