1 /* Utilities for reading/writing fstab, mtab, etc.
2 Copyright (C) 1995-2000, 2001 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, write to the Free
17 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
24 #include <sys/types.h>
25 #include <machine/weakalias.h>
27 /* Prepare to begin reading and/or writing mount table entries from the
28 beginning of FILE. MODE is as for `fopen'. */
30 __setmntent (const char *file, const char *mode)
32 FILE *result = fopen (file, mode);
36 weak_alias (__setmntent, setmntent)
39 /* Close a stream opened with `setmntent'. */
41 __endmntent (FILE *stream)
43 if (stream) /* SunOS 4.x allows for NULL stream */
45 return 1; /* SunOS 4.x says to always return 1 */
47 weak_alias (__endmntent, endmntent)
50 /* Since the values in a line are separated by spaces, a name cannot
51 contain a space. Therefore some programs encode spaces in names
52 by the strings "\040". We undo the encoding when reading an entry.
53 The decoding happens in place. */
55 decode_name (char *buf)
61 if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '4' && rp[3] == '0')
63 /* \040 is a SPACE. */
67 else if (rp[0] == '\\' && rp[1] == '0' && rp[2] == '1' && rp[3] == '2')
73 else if (rp[0] == '\\' && rp[1] == '\\')
75 /* We have to escape \\ to be able to represent all characters. */
81 while (*rp++ != '\0');
87 /* Read one mount table entry from STREAM. Returns a pointer to storage
88 reused on the next call, or null for EOF or error (use feof/ferror to
91 __getmntent_r (FILE *stream, struct mntent *mp, char *buffer, int bufsiz)
101 if (fgets (buffer, bufsiz, stream) == NULL)
103 funlockfile (stream);
107 end_ptr = strchr (buffer, '\n');
108 if (end_ptr != NULL) /* chop newline */
112 /* Not the whole line was read. Do it now but forget it. */
114 while (fgets (tmp, sizeof tmp, stream) != NULL)
115 if (strchr (tmp, '\n') != NULL)
119 head = buffer + strspn (buffer, " \t");
120 /* skip empty lines and comment lines: */
122 while (head[0] == '\0' || head[0] == '#');
124 cp = strsep (&head, " \t");
125 mp->mnt_fsname = cp != NULL ? decode_name (cp) : (char *) "";
127 head += strspn (head, " \t");
128 cp = strsep (&head, " \t");
129 mp->mnt_dir = cp != NULL ? decode_name (cp) : (char *) "";
131 head += strspn (head, " \t");
132 cp = strsep (&head, " \t");
133 mp->mnt_type = cp != NULL ? decode_name (cp) : (char *) "";
135 head += strspn (head, " \t");
136 cp = strsep (&head, " \t");
137 mp->mnt_opts = cp != NULL ? decode_name (cp) : (char *) "";
138 switch (head ? sscanf (head, " %d %d ", &mp->mnt_freq, &mp->mnt_passno) : 0)
147 funlockfile (stream);
151 weak_alias (__getmntent_r, getmntent_r)
154 /* We have to use an encoding for names if they contain spaces or tabs.
155 To be able to represent all characters we also have to escape the
156 backslash itself. This "function" must be a macro since we use
158 #define encode_name(name) \
160 const char *rp = name; \
162 while (*rp != '\0') \
163 if (*rp == ' ' || *rp == '\t' || *rp == '\\') \
170 /* In the worst case the length of the string can increase to \
171 founr times the current length. */ \
175 name = wp = (char *) alloca (strlen (name) * 4 + 1); \
185 else if (*rp == '\t') \
192 else if (*rp == '\\') \
199 while (*rp++ != '\0'); \
204 /* Write the mount table entry described by MNT to STREAM.
205 Return zero on success, nonzero on failure. */
207 __addmntent (FILE *stream, const struct mntent *mnt)
209 struct mntent mntcopy = *mnt;
210 if (fseek (stream, 0, SEEK_END))
213 /* Encode spaces and tabs in the names. */
214 encode_name (mntcopy.mnt_fsname);
215 encode_name (mntcopy.mnt_dir);
216 encode_name (mntcopy.mnt_type);
217 encode_name (mntcopy.mnt_opts);
219 return (fprintf (stream, "%s %s %s %s %d %d\n",
228 weak_alias (__addmntent, addmntent)
231 /* Search MNT->mnt_opts for an option matching OPT.
232 Returns the address of the substring, or null if none found. */
234 __hasmntopt (const struct mntent *mnt, const char *opt)
236 const size_t optlen = strlen (opt);
237 char *rest = mnt->mnt_opts, *p;
239 while ((p = strstr (rest, opt)) != NULL)
243 && (p[optlen] == '\0' ||
248 rest = strchr (rest, ',');
256 weak_alias (__hasmntopt, hasmntopt)