lib/libc/gen/fstab.c

   1 /*
   2  * Copyright (c) 1980, 1988, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if defined(LIBC_SCCS) && !defined(lint)
  35 static char sccsid[] = "@(#)fstab.c     8.1 (Berkeley) 6/4/93";
  36 #endif /* LIBC_SCCS and not lint */
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD$");
  39
  40 #include "namespace.h"
  41 #include <sys/param.h>
  42 #include <sys/mount.h>
  43 #include <sys/stat.h>
  44
  45 #include <errno.h>
  46 #include <fstab.h>
  47 #include <paths.h>
  48 #include <stdio.h>
  49 #include <stdlib.h>
  50 #include <string.h>
  51 #include <unistd.h>
  52 #include "un-namespace.h"
  53
  54 static FILE *_fs_fp;
  55 static struct fstab _fs_fstab;
  56 static int LineNo = 0;
  57 static char *path_fstab;
  58 static char fstab_path[PATH_MAX];
  59 static int fsp_set = 0;
  60
  61 static void error(int);
  62 static void fixfsfile(void);
  63 static int fstabscan(void);
  64
  65 void
  66 setfstab(const char *file)
  67 {
  68
  69         if (file == NULL) {
  70                 path_fstab = _PATH_FSTAB;
  71         } else {
  72                 strncpy(fstab_path, file, PATH_MAX);
  73                 fstab_path[PATH_MAX - 1] = '\0';
  74                 path_fstab = fstab_path;
  75         }
  76         fsp_set = 1;
  77
  78         return;
  79 }
  80
  81 const char *
  82 getfstab (void)
  83 {
  84
  85         if (fsp_set)
  86                 return (path_fstab);
  87         else
  88                 return (_PATH_FSTAB);
  89 }
  90
  91 static void
  92 fixfsfile()
  93 {
  94         static char buf[sizeof(_PATH_DEV) + MNAMELEN];
  95         struct stat sb;
  96         struct statfs sf;
  97
  98         if (strcmp(_fs_fstab.fs_file, "/") != 0)
  99                 return;
 100         if (statfs("/", &sf) != 0)
 101                 return;
 102         if (sf.f_mntfromname[0] == '/')
 103                 buf[0] = '\0';
 104         else
 105                 strcpy(buf, _PATH_DEV);
 106         strcat(buf, sf.f_mntfromname);
 107         if (stat(buf, &sb) != 0 ||
 108             (!S_ISBLK(sb.st_mode) && !S_ISCHR(sb.st_mode)))
 109                 return;
 110         _fs_fstab.fs_spec = buf;
 111 }
 112
 113 static int
 114 fstabscan()
 115 {
 116         char *cp, *p;
 117 #define MAXLINELENGTH   1024
 118         static char line[MAXLINELENGTH];
 119         char subline[MAXLINELENGTH];
 120         int typexx;
 121
 122         for (;;) {
 123
 124                 if (!(p = fgets(line, sizeof(line), _fs_fp)))
 125                         return(0);
 126 /* OLD_STYLE_FSTAB */
 127                 ++LineNo;
 128                 if (*line == '#' || *line == '\n')
 129                         continue;
 130                 if (!strpbrk(p, " \t")) {
 131                         _fs_fstab.fs_spec = strsep(&p, ":\n");
 132                         _fs_fstab.fs_file = strsep(&p, ":\n");
 133                         fixfsfile();
 134                         _fs_fstab.fs_type = strsep(&p, ":\n");
 135                         if (_fs_fstab.fs_type) {
 136                                 if (!strcmp(_fs_fstab.fs_type, FSTAB_XX))
 137                                         continue;
 138                                 _fs_fstab.fs_mntops = _fs_fstab.fs_type;
 139                                 _fs_fstab.fs_vfstype =
 140                                     strcmp(_fs_fstab.fs_type, FSTAB_SW) ?
 141                                     "ufs" : "swap";
 142                                 if ((cp = strsep(&p, ":\n")) != NULL) {
 143                                         _fs_fstab.fs_freq = atoi(cp);
 144                                         if ((cp = strsep(&p, ":\n")) != NULL) {
 145                                                 _fs_fstab.fs_passno = atoi(cp);
 146                                                 return(1);
 147                                         }
 148                                 }
 149                         }
 150                         goto bad;
 151                 }
 152 /* OLD_STYLE_FSTAB */
 153                 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
 154                         ;
 155                 _fs_fstab.fs_spec = cp;
 156                 if (!_fs_fstab.fs_spec || *_fs_fstab.fs_spec == '#')
 157                         continue;
 158                 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
 159                         ;
 160                 _fs_fstab.fs_file = cp;
 161                 fixfsfile();
 162                 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
 163                         ;
 164                 _fs_fstab.fs_vfstype = cp;
 165                 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
 166                         ;
 167                 _fs_fstab.fs_mntops = cp;
 168                 if (_fs_fstab.fs_mntops == NULL)
 169                         goto bad;
 170                 _fs_fstab.fs_freq = 0;
 171                 _fs_fstab.fs_passno = 0;
 172                 while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
 173                         ;
 174                 if (cp != NULL) {
 175                         _fs_fstab.fs_freq = atoi(cp);
 176                         while ((cp = strsep(&p, " \t\n")) != NULL && *cp == '\0')
 177                                 ;
 178                         if (cp != NULL)
 179                                 _fs_fstab.fs_passno = atoi(cp);
 180                 }
 181                 strcpy(subline, _fs_fstab.fs_mntops);
 182                 p = subline;
 183                 for (typexx = 0, cp = strsep(&p, ","); cp;
 184                      cp = strsep(&p, ",")) {
 185                         if (strlen(cp) != 2)
 186                                 continue;
 187                         if (!strcmp(cp, FSTAB_RW)) {
 188                                 _fs_fstab.fs_type = FSTAB_RW;
 189                                 break;
 190                         }
 191                         if (!strcmp(cp, FSTAB_RQ)) {
 192                                 _fs_fstab.fs_type = FSTAB_RQ;
 193                                 break;
 194                         }
 195                         if (!strcmp(cp, FSTAB_RO)) {
 196                                 _fs_fstab.fs_type = FSTAB_RO;
 197                                 break;
 198                         }
 199                         if (!strcmp(cp, FSTAB_SW)) {
 200                                 _fs_fstab.fs_type = FSTAB_SW;
 201                                 break;
 202                         }
 203                         if (!strcmp(cp, FSTAB_XX)) {
 204                                 _fs_fstab.fs_type = FSTAB_XX;
 205                                 typexx++;
 206                                 break;
 207                         }
 208                 }
 209                 if (typexx)
 210                         continue;
 211                 if (cp != NULL)
 212                         return(1);
 213
 214 bad:            /* no way to distinguish between EOF and syntax error */
 215                 error(EFTYPE);
 216         }
 217         /* NOTREACHED */
 218 }
 219
 220 struct fstab *
 221 getfsent()
 222 {
 223         if ((!_fs_fp && !setfsent()) || !fstabscan())
 224                 return((struct fstab *)NULL);
 225         return(&_fs_fstab);
 226 }
 227
 228 struct fstab *
 229 getfsspec(name)
 230         const char *name;
 231 {
 232         if (setfsent())
 233                 while (fstabscan())
 234                         if (!strcmp(_fs_fstab.fs_spec, name))
 235                                 return(&_fs_fstab);
 236         return((struct fstab *)NULL);
 237 }
 238
 239 struct fstab *
 240 getfsfile(name)
 241         const char *name;
 242 {
 243         if (setfsent())
 244                 while (fstabscan())
 245                         if (!strcmp(_fs_fstab.fs_file, name))
 246                                 return(&_fs_fstab);
 247         return((struct fstab *)NULL);
 248 }
 249
 250 int
 251 setfsent()
 252 {
 253         if (_fs_fp) {
 254                 rewind(_fs_fp);
 255                 LineNo = 0;
 256                 return(1);
 257         }
 258         if (fsp_set == 0) {
 259                 if (issetugid())
 260                         setfstab(NULL);
 261                 else
 262                         setfstab(getenv("PATH_FSTAB"));
 263         }
 264         if ((_fs_fp = fopen(path_fstab, "r")) != NULL) {
 265                 LineNo = 0;
 266                 return(1);
 267         }
 268         error(errno);
 269         return(0);
 270 }
 271
 272 void
 273 endfsent()
 274 {
 275         if (_fs_fp) {
 276                 (void)fclose(_fs_fp);
 277                 _fs_fp = NULL;
 278         }
 279
 280         fsp_set = 0;
 281 }
 282
 283 static void
 284 error(err)
 285         int err;
 286 {
 287         char *p;
 288         char num[30];
 289
 290         (void)_write(STDERR_FILENO, "fstab: ", 7);
 291         (void)_write(STDERR_FILENO, path_fstab, strlen(path_fstab));
 292         (void)_write(STDERR_FILENO, ":", 1);
 293         sprintf(num, "%d: ", LineNo);
 294         (void)_write(STDERR_FILENO, num, strlen(num));
 295         p = strerror(err);
 296         (void)_write(STDERR_FILENO, p, strlen(p));
 297         (void)_write(STDERR_FILENO, "\n", 1);
 298 }