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