1/* Copyright (C) 1991-2016 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 <http://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <stddef.h>
20#include <unistd.h>
21#include <limits.h>
22#include <fcntl.h>
23#include <sys/stat.h>
24#include <sys/statfs.h>
25#include <sys/statvfs.h>
26
27
28/* Get file-specific information about PATH. */
29long int
30__pathconf (const char *path, int name)
31{
32 if (path[0] == '\0')
33 {
34 __set_errno (ENOENT);
35 return -1;
36 }
37
38 switch (name)
39 {
40 default:
41 __set_errno (EINVAL);
42 return -1;
43
44 case _PC_LINK_MAX:
45#ifdef LINK_MAX
46 return LINK_MAX;
47#else
48 return -1;
49#endif
50
51 case _PC_MAX_CANON:
52#ifdef MAX_CANON
53 return MAX_CANON;
54#else
55 return -1;
56#endif
57
58 case _PC_MAX_INPUT:
59#ifdef MAX_INPUT
60 return MAX_INPUT;
61#else
62 return -1;
63#endif
64
65 case _PC_NAME_MAX:
66#ifdef NAME_MAX
67 {
68 struct statvfs64 sv;
69 int save_errno = errno;
70
71 if (__statvfs64 (path, &sv) < 0)
72 {
73 if (errno == ENOSYS)
74 {
75 errno = save_errno;
76 return NAME_MAX;
77 }
78 return -1;
79 }
80 else
81 {
82 return sv.f_namemax;
83 }
84 }
85#else
86 return -1;
87#endif
88
89 case _PC_PATH_MAX:
90#ifdef PATH_MAX
91 return PATH_MAX;
92#else
93 return -1;
94#endif
95
96 case _PC_PIPE_BUF:
97#ifdef PIPE_BUF
98 return PIPE_BUF;
99#else
100 return -1;
101#endif
102
103 case _PC_CHOWN_RESTRICTED:
104#ifdef _POSIX_CHOWN_RESTRICTED
105 return _POSIX_CHOWN_RESTRICTED;
106#else
107 return -1;
108#endif
109
110 case _PC_NO_TRUNC:
111#ifdef _POSIX_NO_TRUNC
112 return _POSIX_NO_TRUNC;
113#else
114 return -1;
115#endif
116
117 case _PC_VDISABLE:
118#ifdef _POSIX_VDISABLE
119 return _POSIX_VDISABLE;
120#else
121 return -1;
122#endif
123
124 case _PC_SYNC_IO:
125#ifdef _POSIX_SYNC_IO
126 return _POSIX_SYNC_IO;
127#else
128 return -1;
129#endif
130
131 case _PC_ASYNC_IO:
132#ifdef _POSIX_ASYNC_IO
133 {
134 /* AIO is only allowed on regular files and block devices. */
135 struct stat64 st;
136
137 if (__xstat64 (_STAT_VER, path, &st) < 0
138 || (! S_ISREG (st.st_mode) && ! S_ISBLK (st.st_mode)))
139 return -1;
140 else
141 return 1;
142 }
143#else
144 return -1;
145#endif
146
147 case _PC_PRIO_IO:
148#ifdef _POSIX_PRIO_IO
149 return _POSIX_PRIO_IO;
150#else
151 return -1;
152#endif
153
154 case _PC_SOCK_MAXBUF:
155#ifdef SOCK_MAXBUF
156 return SOCK_MAXBUF;
157#else
158 return -1;
159#endif
160
161 case _PC_FILESIZEBITS:
162#ifdef FILESIZEBITS
163 return FILESIZEBITS;
164#else
165 /* We let platforms with larger file sizes overwrite this value. */
166 return 32;
167#endif
168
169 case _PC_REC_INCR_XFER_SIZE:
170 /* XXX It is not entirely clear what the limit is supposed to do.
171 What is incremented? */
172 return -1;
173
174 case _PC_REC_MAX_XFER_SIZE:
175 /* XXX It is not entirely clear what the limit is supposed to do.
176 In general there is no top limit of the number of bytes which
177 case be transported at once. */
178 return -1;
179
180 case _PC_REC_MIN_XFER_SIZE:
181 {
182 /* XXX It is not entirely clear what the limit is supposed to do.
183 I assume this is the block size of the filesystem. */
184 struct statvfs64 sv;
185
186 if (__statvfs64 (path, &sv) < 0)
187 return -1;
188 return sv.f_bsize;
189 }
190
191 case _PC_REC_XFER_ALIGN:
192 {
193 /* XXX It is not entirely clear what the limit is supposed to do.
194 I assume that the number should reflect the minimal block
195 alignment. */
196 struct statvfs64 sv;
197
198 if (__statvfs64 (path, &sv) < 0)
199 return -1;
200 return sv.f_frsize;
201 }
202
203 case _PC_ALLOC_SIZE_MIN:
204 {
205 /* XXX It is not entirely clear what the limit is supposed to do.
206 I assume that the number should reflect the minimal block
207 alignment. */
208 struct statvfs64 sv;
209
210 if (__statvfs64 (path, &sv) < 0)
211 return -1;
212 return sv.f_frsize;
213 }
214
215 case _PC_SYMLINK_MAX:
216 /* In general there are no limits. If a system has one it should
217 overwrite this case. */
218 return -1;
219
220 case _PC_2_SYMLINKS:
221 /* Unix systems generally have symlinks. */
222 return 1;
223 }
224}
225
226#undef __pathconf
227weak_alias (__pathconf, pathconf)
228