1 /* Test that openat works.
2 Copyright (C) 2009-2021 Free Software Foundation, Inc.
3
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
8
9 This program 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
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <https://www.gnu.org/licenses/>. */
16
17 /* Written by Eric Blake <ebb9@byu.net>, 2009. */
18
19 #include <config.h>
20
21 #include <fcntl.h>
22
23 #include "signature.h"
24 SIGNATURE_CHECK (openat, int, (int, char const *, int, ...));
25
26 #include <errno.h>
27 #include <stdarg.h>
28 #include <stdbool.h>
29 #include <stdio.h>
30 #include <unistd.h>
31
32 #include "macros.h"
33
34 #define BASE "test-openat.t"
35
36 #include "test-open.h"
37
38 static int dfd = AT_FDCWD;
39
40 /* Wrapper around openat to test open behavior. */
41 static int
do_open(char const * name,int flags,...)42 do_open (char const *name, int flags, ...)
43 {
44 if (flags & O_CREAT)
45 {
46 mode_t mode = 0;
47 va_list arg;
48 va_start (arg, flags);
49
50 /* We have to use PROMOTED_MODE_T instead of mode_t, otherwise GCC 4
51 creates crashing code when 'mode_t' is smaller than 'int'. */
52 mode = va_arg (arg, PROMOTED_MODE_T);
53
54 va_end (arg);
55 return openat (dfd, name, flags, mode);
56 }
57 return openat (dfd, name, flags);
58 }
59
60 int
main(int argc _GL_UNUSED,char * argv[])61 main (int argc _GL_UNUSED, char *argv[])
62 {
63 int result;
64
65 /* Test behaviour for invalid file descriptors. */
66 {
67 errno = 0;
68 ASSERT (openat (-1, "foo", O_RDONLY) == -1);
69 ASSERT (errno == EBADF);
70 }
71 {
72 close (99);
73 errno = 0;
74 ASSERT (openat (99, "foo", O_RDONLY) == -1);
75 ASSERT (errno == EBADF);
76 }
77
78 /* Basic checks. */
79 result = test_open (do_open, false);
80 dfd = open (".", O_RDONLY);
81 ASSERT (0 <= dfd);
82 ASSERT (test_open (do_open, false) == result);
83 ASSERT (close (dfd) == 0);
84
85 /* Check that even when *-safer modules are in use, plain openat can
86 land in fd 0. Do this test last, since it is destructive to
87 stdin. */
88 ASSERT (close (STDIN_FILENO) == 0);
89 ASSERT (openat (AT_FDCWD, ".", O_RDONLY) == STDIN_FILENO);
90 {
91 dfd = open (".", O_RDONLY);
92 ASSERT (STDIN_FILENO < dfd);
93 ASSERT (chdir ("..") == 0);
94 ASSERT (close (STDIN_FILENO) == 0);
95 ASSERT (openat (dfd, ".", O_RDONLY) == STDIN_FILENO);
96 ASSERT (close (dfd) == 0);
97 }
98 return result;
99 }
100