1 /* Copyright (C) 1991-2022 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 <errno.h>
19 #include <stdarg.h>
20 #include <sysdep.h>
21 #include <ulimit.h>
22 #include <unistd.h>
23 #include <limits.h>
24 #include <sys/resource.h>
25
26 /* Function depends on CMD:
27 1 = Return the limit on the size of a file, in units of 512 bytes.
28 2 = Set the limit on the size of a file to NEWLIMIT. Only the
29 super-user can increase the limit.
30 3 = illegal due to shared libraries; normally is
31 (Return the maximum possible address of the data segment.)
32 4 = Return the maximum number of files that the calling process
33 can open.
34 Returns -1 on errors. */
35 long int
__ulimit(int cmd,...)36 __ulimit (int cmd, ...)
37 {
38 struct rlimit limit;
39 va_list va;
40 long int result = -1;
41
42 va_start (va, cmd);
43
44 switch (cmd)
45 {
46 case UL_GETFSIZE:
47 /* Get limit on file size. */
48 if (__getrlimit (RLIMIT_FSIZE, &limit) == 0)
49 /* Convert from bytes to 512 byte units. */
50 result = (limit.rlim_cur == RLIM_INFINITY
51 ? LONG_MAX : limit.rlim_cur / 512);
52 break;
53
54 case UL_SETFSIZE:
55 /* Set limit on file size. */
56 {
57 long int newlimit = va_arg (va, long int);
58 long int newlen;
59
60 if ((rlim_t) newlimit > RLIM_INFINITY / 512)
61 {
62 limit.rlim_cur = RLIM_INFINITY;
63 limit.rlim_max = RLIM_INFINITY;
64 newlen = LONG_MAX;
65 }
66 else
67 {
68 limit.rlim_cur = newlimit * 512;
69 limit.rlim_max = newlimit * 512;
70 newlen = newlimit;
71 }
72
73 result = __setrlimit (RLIMIT_FSIZE, &limit);
74 if (result != -1)
75 result = newlen;
76 }
77 break;
78
79 case __UL_GETOPENMAX:
80 result = __sysconf (_SC_OPEN_MAX);
81 break;
82
83 default:
84 __set_errno (EINVAL);
85 }
86
87 va_end (va);
88
89 return result;
90 }
91
92 weak_alias (__ulimit, ulimit);
93