1 /* Copyright (C) 1995-2022 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18 #include <fstab.h>
19 #include <mntent.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <libc-lock.h>
24
25 #define BUFFER_SIZE 0x1fc0
26
27 struct fstab_state
28 {
29 FILE *fs_fp;
30 char *fs_buffer;
31 struct mntent fs_mntres;
32 struct fstab fs_ret;
33 };
34
35 static struct fstab_state *fstab_init (int opt_rewind);
36 static struct mntent *fstab_fetch (struct fstab_state *state);
37 static struct fstab *fstab_convert (struct fstab_state *state);
38
39 static struct fstab_state fstab_state;
40
41
42 int
setfsent(void)43 setfsent (void)
44 {
45 return fstab_init (1) != NULL;
46 }
47
48
49 struct fstab *
getfsent(void)50 getfsent (void)
51 {
52 struct fstab_state *state;
53
54 state = fstab_init (0);
55 if (state == NULL)
56 return NULL;
57 if (fstab_fetch (state) == NULL)
58 return NULL;
59 return fstab_convert (state);
60 }
61
62
63 struct fstab *
getfsspec(const char * name)64 getfsspec (const char *name)
65 {
66 struct fstab_state *state;
67 struct mntent *m;
68
69 state = fstab_init (1);
70 if (state == NULL)
71 return NULL;
72 while ((m = fstab_fetch (state)) != NULL)
73 if (strcmp (m->mnt_fsname, name) == 0)
74 return fstab_convert (state);
75 return NULL;
76 }
77
78
79 struct fstab *
getfsfile(const char * name)80 getfsfile (const char *name)
81 {
82 struct fstab_state *state;
83 struct mntent *m;
84
85 state = fstab_init (1);
86 if (state == NULL)
87 return NULL;
88 while ((m = fstab_fetch (state)) != NULL)
89 if (strcmp (m->mnt_dir, name) == 0)
90 return fstab_convert (state);
91 return NULL;
92 }
93
94
95 void
endfsent(void)96 endfsent (void)
97 {
98 struct fstab_state *state;
99
100 state = &fstab_state;
101 if (state->fs_fp != NULL)
102 {
103 (void) __endmntent (state->fs_fp);
104 state->fs_fp = NULL;
105 }
106 }
107
108
109 static struct fstab_state *
fstab_init(int opt_rewind)110 fstab_init (int opt_rewind)
111 {
112 struct fstab_state *state;
113 char *buffer;
114 FILE *fp;
115
116 state = &fstab_state;
117
118 buffer = state->fs_buffer;
119 if (buffer == NULL)
120 {
121 buffer = (char *) malloc (BUFFER_SIZE);
122 if (buffer == NULL)
123 return NULL;
124 state->fs_buffer = buffer;
125 }
126
127 fp = state->fs_fp;
128 if (fp != NULL)
129 {
130 if (opt_rewind)
131 rewind (fp);
132 }
133 else
134 {
135 fp = __setmntent (_PATH_FSTAB, "r");
136 if (fp == NULL)
137 return NULL;
138 state->fs_fp = fp;
139 }
140
141 return state;
142 }
143
144
145 static struct mntent *
fstab_fetch(struct fstab_state * state)146 fstab_fetch (struct fstab_state *state)
147 {
148 return __getmntent_r (state->fs_fp, &state->fs_mntres,
149 state->fs_buffer, BUFFER_SIZE);
150 }
151
152
153 static struct fstab *
fstab_convert(struct fstab_state * state)154 fstab_convert (struct fstab_state *state)
155 {
156 struct mntent *m;
157 struct fstab *f;
158
159 m = &state->fs_mntres;
160 f = &state->fs_ret;
161
162 f->fs_spec = m->mnt_fsname;
163 f->fs_file = m->mnt_dir;
164 f->fs_vfstype = m->mnt_type;
165 f->fs_mntops = m->mnt_opts;
166 f->fs_type = (__hasmntopt (m, FSTAB_RW) ? FSTAB_RW
167 : __hasmntopt (m, FSTAB_RQ) ? FSTAB_RQ
168 : __hasmntopt (m, FSTAB_RO) ? FSTAB_RO
169 : __hasmntopt (m, FSTAB_SW) ? FSTAB_SW
170 : __hasmntopt (m, FSTAB_XX) ? FSTAB_XX
171 : "??");
172 f->fs_freq = m->mnt_freq;
173 f->fs_passno = m->mnt_passno;
174 return f;
175 }
176
177
178 /* Make sure the memory is freed if the programs ends while in
179 memory-debugging mode and something actually was allocated. */
libc_freeres_fn(fstab_free)180 libc_freeres_fn (fstab_free)
181 {
182 char *buffer;
183
184 buffer = fstab_state.fs_buffer;
185 free ((void *) buffer);
186 }
187