1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/* Check posix_spawn add file actions.
Copyright (C) 2016-2023 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <spawn.h>
#include <error.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
#include <sys/resource.h>
#include <fcntl.h>
#include <paths.h>
#include <intprops.h>
#include <support/check.h>
#include <support/temp_file.h>
#include <support/xunistd.h>
#include <tst-spawn.h>
static int
do_test (void)
{
/* The test checks if posix_spawn open file action close the file descriptor
before opening a new one in case the input file descriptor is already
opened. It does by exhausting all file descriptors on the process before
issue posix_spawn. It then issues a posix_spawn for '/bin/sh echo $$'
and add two rules:
1. Redirect stdout to a temporary filepath
2. Redirect stderr to stdout
If the implementation does not close the file 1. will fail with
EMFILE. */
struct rlimit rl;
int max_fd = 24;
/* Set maximum number of file descriptor to a low value to avoid open
too many files in environments where RLIMIT_NOFILE is large and to
limit the array size to track the opened file descriptors. */
if (getrlimit (RLIMIT_NOFILE, &rl) == -1)
FAIL_EXIT1 ("getrlimit (RLIMIT_NOFILE): %m");
max_fd = (rl.rlim_cur < max_fd ? rl.rlim_cur : max_fd);
rl.rlim_cur = max_fd;
if (setrlimit (RLIMIT_NOFILE, &rl) == 1)
FAIL_EXIT1 ("setrlimit (RLIMIT_NOFILE): %m");
/* Exhauste the file descriptor limit with temporary files. */
int files[max_fd];
int nfiles = 0;
for (; nfiles < max_fd; nfiles++)
{
int fd = create_temp_file ("tst-spawn3.", NULL);
if (fd == -1)
{
if (errno != EMFILE)
FAIL_EXIT1 ("create_temp_file: %m");
break;
}
files[nfiles] = fd;
}
TEST_VERIFY_EXIT (nfiles != 0);
posix_spawn_file_actions_t a;
TEST_COMPARE (posix_spawn_file_actions_init (&a), 0);
/* Executes a /bin/sh echo $$ 2>&1 > ${objpfx}tst-spawn3.pid . */
const char pidfile[] = OBJPFX "tst-spawn3.pid";
TEST_COMPARE (posix_spawn_file_actions_addopen (&a, STDOUT_FILENO, pidfile,
O_WRONLY| O_CREAT | O_TRUNC,
0644),
0);
TEST_COMPARE (posix_spawn_file_actions_adddup2 (&a, STDOUT_FILENO,
STDERR_FILENO),
0);
/* Since execve (called by posix_spawn) might require to open files to
actually execute the shell script, setup to close the temporary file
descriptors. */
int maxnfiles =
#ifdef TST_SPAWN_PIDFD
/* The sparing file descriptor will be returned as the pid descriptor,
otherwise clone fail with EMFILE. */
nfiles - 1;
#else
nfiles;
#endif
for (int i=0; i<maxnfiles; i++)
TEST_COMPARE (posix_spawn_file_actions_addclose (&a, files[i]), 0);
char *spawn_argv[] = { (char *) _PATH_BSHELL, (char *) "-c",
(char *) "echo $$", NULL };
PID_T_TYPE pid;
{
int r = POSIX_SPAWN (&pid, _PATH_BSHELL, &a, NULL, spawn_argv, NULL);
if (r == ENOSYS)
FAIL_UNSUPPORTED ("kernel does not support CLONE_PIDFD clone flag");
#ifdef TST_SPAWN_PIDFD
TEST_COMPARE (r, EMFILE);
/* Free up one file descriptor, so posix_spawn_pidfd_ex can return it. */
xclose (files[nfiles-1]);
nfiles--;
r = POSIX_SPAWN (&pid, _PATH_BSHELL, &a, NULL, spawn_argv, NULL);
#endif
TEST_COMPARE (r, 0);
}
siginfo_t sinfo;
TEST_COMPARE (WAITID (P_PID, pid, &sinfo, WEXITED), 0);
TEST_COMPARE (sinfo.si_code, CLD_EXITED);
TEST_COMPARE (sinfo.si_status, 0);
/* Close the temporary files descriptor so it can check posix_spawn
output. */
for (int i=0; i<nfiles; i++)
xclose (files[i]);
int pidfd = xopen (pidfile, O_RDONLY, 0);
char buf[INT_BUFSIZE_BOUND (pid_t)];
ssize_t n = read (pidfd, buf, sizeof (buf));
TEST_VERIFY (n < sizeof buf && n >= 0);
xunlink (pidfile);
/* We only expect to read the PID. */
char *endp;
long int rpid = strtol (buf, &endp, 10);
TEST_VERIFY (*endp == '\n' && endp != buf);
TEST_COMPARE (rpid, sinfo.si_pid);
return 0;
}
#include <support/test-driver.c>
|