1 /* Utilities for reading/writing fstab, mtab, etc.
2 Copyright (C) 1995-2000, 2001, 2002, 2003, 2006
3 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
24 #include <stdio_ext.h>
26 #include <sys/types.h>
29 # define flockfile(s) _IO_flockfile (s)
30 # define funlockfile(s) _IO_funlockfile (s)
37 /* Prepare to begin reading and/or writing mount table entries from the
38 beginning of FILE. MODE is as for `fopen'. */
40 __setmntent (const char *file
, const char *mode
)
42 /* Extend the mode parameter with "c" to disable cancellation in the
44 size_t modelen
= strlen (mode
);
45 char newmode
[modelen
+ 2];
46 memcpy (mempcpy (newmode
, mode
, modelen
), "c", 2);
47 FILE *result
= fopen (file
, newmode
);
50 /* We do the locking ourselves. */
51 __fsetlocking (result
, FSETLOCKING_BYCALLER
);
56 weak_alias (__setmntent
, setmntent
)
59 /* Close a stream opened with `setmntent'. */
61 __endmntent (FILE *stream
)
63 if (stream
) /* SunOS 4.x allows for NULL stream */
65 return 1; /* SunOS 4.x says to always return 1 */
68 weak_alias (__endmntent
, endmntent
)
71 /* Since the values in a line are separated by spaces, a name cannot
72 contain a space. Therefore some programs encode spaces in names
73 by the strings "\040". We undo the encoding when reading an entry.
74 The decoding happens in place. */
76 decode_name (char *buf
)
82 if (rp
[0] == '\\' && rp
[1] == '0' && rp
[2] == '4' && rp
[3] == '0')
84 /* \040 is a SPACE. */
88 else if (rp
[0] == '\\' && rp
[1] == '0' && rp
[2] == '1' && rp
[3] == '1')
94 else if (rp
[0] == '\\' && rp
[1] == '0' && rp
[2] == '1' && rp
[3] == '2')
96 /* \012 is a NEWLINE. */
100 else if (rp
[0] == '\\' && rp
[1] == '\\')
102 /* We have to escape \\ to be able to represent all characters. */
106 else if (rp
[0] == '\\' && rp
[1] == '1' && rp
[2] == '3' && rp
[3] == '4')
108 /* \134 is also \\. */
114 while (*rp
++ != '\0');
120 /* Read one mount table entry from STREAM. Returns a pointer to storage
121 reused on the next call, or null for EOF or error (use feof/ferror to
124 __getmntent_r (FILE *stream
, struct mntent
*mp
, char *buffer
, int bufsiz
)
134 if (fgets_unlocked (buffer
, bufsiz
, stream
) == NULL
)
136 funlockfile (stream
);
140 end_ptr
= strchr (buffer
, '\n');
141 if (end_ptr
!= NULL
) /* chop newline */
145 /* Not the whole line was read. Do it now but forget it. */
147 while (fgets_unlocked (tmp
, sizeof tmp
, stream
) != NULL
)
148 if (strchr (tmp
, '\n') != NULL
)
152 head
= buffer
+ strspn (buffer
, " \t");
153 /* skip empty lines and comment lines: */
155 while (head
[0] == '\0' || head
[0] == '#');
157 cp
= __strsep (&head
, " \t");
158 mp
->mnt_fsname
= cp
!= NULL
? decode_name (cp
) : (char *) "";
160 head
+= strspn (head
, " \t");
161 cp
= __strsep (&head
, " \t");
162 mp
->mnt_dir
= cp
!= NULL
? decode_name (cp
) : (char *) "";
164 head
+= strspn (head
, " \t");
165 cp
= __strsep (&head
, " \t");
166 mp
->mnt_type
= cp
!= NULL
? decode_name (cp
) : (char *) "";
168 head
+= strspn (head
, " \t");
169 cp
= __strsep (&head
, " \t");
170 mp
->mnt_opts
= cp
!= NULL
? decode_name (cp
) : (char *) "";
171 switch (head
? sscanf (head
, " %d %d ", &mp
->mnt_freq
, &mp
->mnt_passno
) : 0)
180 funlockfile (stream
);
184 INTDEF(__getmntent_r
)
185 weak_alias (__getmntent_r
, getmntent_r
)
188 /* We have to use an encoding for names if they contain spaces or tabs.
189 To be able to represent all characters we also have to escape the
190 backslash itself. This "function" must be a macro since we use
192 #define encode_name(name) \
194 const char *rp = name; \
196 while (*rp != '\0') \
197 if (*rp == ' ' || *rp == '\t' || *rp == '\\') \
204 /* In the worst case the length of the string can increase to \
205 founr times the current length. */ \
209 name = wp = (char *) alloca (strlen (name) * 4 + 1); \
219 else if (*rp == '\t') \
226 else if (*rp == '\n') \
233 else if (*rp == '\\') \
240 while (*rp++ != '\0'); \
245 /* Write the mount table entry described by MNT to STREAM.
246 Return zero on success, nonzero on failure. */
248 __addmntent (FILE *stream
, const struct mntent
*mnt
)
250 struct mntent mntcopy
= *mnt
;
251 if (fseek (stream
, 0, SEEK_END
))
254 /* Encode spaces and tabs in the names. */
255 encode_name (mntcopy
.mnt_fsname
);
256 encode_name (mntcopy
.mnt_dir
);
257 encode_name (mntcopy
.mnt_type
);
258 encode_name (mntcopy
.mnt_opts
);
260 return (fprintf (stream
, "%s %s %s %s %d %d\n",
269 weak_alias (__addmntent
, addmntent
)
272 /* Search MNT->mnt_opts for an option matching OPT.
273 Returns the address of the substring, or null if none found. */
275 __hasmntopt (const struct mntent
*mnt
, const char *opt
)
277 const size_t optlen
= strlen (opt
);
278 char *rest
= mnt
->mnt_opts
, *p
;
280 while ((p
= strstr (rest
, opt
)) != NULL
)
282 if ((p
== rest
|| p
[-1] == ',')
283 && (p
[optlen
] == '\0' || p
[optlen
] == '=' || p
[optlen
] == ','))
286 rest
= strchr (p
, ',');
294 weak_alias (__hasmntopt
, hasmntopt
)