4 * Copyright (c) 2003-2008 Fabrice Bellard
5 * Copyright (c) 2010 Red Hat, Inc.
7 * Permission is hereby granted, free of charge, to any person obtaining a copy
8 * of this software and associated documentation files (the "Software"), to deal
9 * in the Software without restriction, including without limitation the rights
10 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11 * copies of the Software, and to permit persons to whom the Software is
12 * furnished to do so, subject to the following conditions:
14 * The above copyright notice and this permission notice shall be included in
15 * all copies or substantial portions of the Software.
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
29 #include <sys/types.h>
31 /*needed for MAP_POPULATE before including qemu-options.h */
36 /* Needed early for CONFIG_BSD etc. */
37 #include "config-host.h"
39 #include "net/slirp.h"
40 #include "qemu-options.h"
43 #include <sys/prctl.h>
44 #include <sys/syscall.h>
48 #include <sys/eventfd.h>
51 static struct passwd
*user_pwd
;
52 static const char *chroot_dir
;
56 void os_setup_early_signal_handling(void)
59 sigfillset(&act
.sa_mask
);
61 act
.sa_handler
= SIG_IGN
;
62 sigaction(SIGPIPE
, &act
, NULL
);
65 static void termsig_handler(int signal
, siginfo_t
*info
, void *c
)
67 qemu_system_killed(info
->si_signo
, info
->si_pid
);
70 static void sigchld_handler(int signal
)
72 waitpid(-1, NULL
, WNOHANG
);
75 void os_setup_signal_handling(void)
79 memset(&act
, 0, sizeof(act
));
80 act
.sa_sigaction
= termsig_handler
;
81 act
.sa_flags
= SA_SIGINFO
;
82 sigaction(SIGINT
, &act
, NULL
);
83 sigaction(SIGHUP
, &act
, NULL
);
84 sigaction(SIGTERM
, &act
, NULL
);
86 act
.sa_handler
= sigchld_handler
;
87 act
.sa_flags
= SA_NOCLDSTOP
;
88 sigaction(SIGCHLD
, &act
, NULL
);
91 /* Find a likely location for support files using the location of the binary.
92 For installed binaries this will be "$bindir/../share/qemu". When
93 running from the build tree this will be "$bindir/../pc-bios". */
94 #define SHARE_SUFFIX "/share/qemu"
95 #define BUILD_SUFFIX "/pc-bios"
96 char *os_find_datadir(const char *argv0
)
104 #if defined(__linux__)
107 len
= readlink("/proc/self/exe", buf
, sizeof(buf
) - 1);
113 #elif defined(__FreeBSD__)
115 static int mib
[4] = {CTL_KERN
, KERN_PROC
, KERN_PROC_PATHNAME
, -1};
116 size_t len
= sizeof(buf
) - 1;
119 if (!sysctl(mib
, ARRAY_SIZE(mib
), buf
, &len
, NULL
, 0) &&
121 buf
[sizeof(buf
) - 1] = '\0';
126 /* If we don't have any way of figuring out the actual executable
127 location then try argv[0]. */
129 p
= realpath(argv0
, buf
);
137 max_len
= strlen(dir
) +
138 MAX(strlen(SHARE_SUFFIX
), strlen(BUILD_SUFFIX
)) + 1;
139 res
= qemu_mallocz(max_len
);
140 snprintf(res
, max_len
, "%s%s", dir
, SHARE_SUFFIX
);
141 if (access(res
, R_OK
)) {
142 snprintf(res
, max_len
, "%s%s", dir
, BUILD_SUFFIX
);
143 if (access(res
, R_OK
)) {
154 void os_set_proc_name(const char *s
)
156 #if defined(PR_SET_NAME)
160 name
[sizeof(name
) - 1] = 0;
161 strncpy(name
, s
, sizeof(name
));
162 /* Could rewrite argv[0] too, but that's a bit more complicated.
163 This simple way is enough for `top'. */
164 if (prctl(PR_SET_NAME
, name
)) {
165 perror("unable to change process name");
169 fprintf(stderr
, "Change of process name not supported by your OS\n");
175 * Parse OS specific command line options.
176 * return 0 if option handled, -1 otherwise
178 void os_parse_cmd_args(int index
, const char *optarg
)
182 case QEMU_OPTION_smb
:
183 if (net_slirp_smb(optarg
) < 0)
187 case QEMU_OPTION_runas
:
188 user_pwd
= getpwnam(optarg
);
190 fprintf(stderr
, "User \"%s\" doesn't exist\n", optarg
);
194 case QEMU_OPTION_chroot
:
197 case QEMU_OPTION_daemonize
:
204 static void change_process_uid(void)
207 if (setgid(user_pwd
->pw_gid
) < 0) {
208 fprintf(stderr
, "Failed to setgid(%d)\n", user_pwd
->pw_gid
);
211 if (setuid(user_pwd
->pw_uid
) < 0) {
212 fprintf(stderr
, "Failed to setuid(%d)\n", user_pwd
->pw_uid
);
215 if (setuid(0) != -1) {
216 fprintf(stderr
, "Dropping privileges failed\n");
222 static void change_root(void)
225 if (chroot(chroot_dir
) < 0) {
226 fprintf(stderr
, "chroot failed\n");
230 perror("not able to chdir to /");
237 void os_daemonize(void)
253 len
= read(fds
[0], &status
, 1);
254 if (len
== -1 && (errno
== EINTR
))
259 else if (status
== 1) {
260 fprintf(stderr
, "Could not acquire pidfile: %s\n", strerror(errno
));
268 qemu_set_cloexec(fds
[1]);
280 signal(SIGTSTP
, SIG_IGN
);
281 signal(SIGTTOU
, SIG_IGN
);
282 signal(SIGTTIN
, SIG_IGN
);
286 void os_setup_post(void)
295 len
= write(fds
[1], &status
, 1);
296 if (len
== -1 && (errno
== EINTR
))
303 perror("not able to chdir to /");
306 TFR(fd
= qemu_open("/dev/null", O_RDWR
));
312 change_process_uid();
323 void os_pidfile_error(void)
327 if (write(fds
[1], &status
, 1) != 1) {
328 perror("daemonize. Writing to pipe\n");
331 fprintf(stderr
, "Could not acquire pid file: %s\n", strerror(errno
));
334 void os_set_line_buffering(void)
336 setvbuf(stdout
, NULL
, _IOLBF
, 0);
340 * Creates an eventfd that looks like a pipe and has EFD_CLOEXEC set.
342 int qemu_eventfd(int fds
[2])
344 #ifdef CONFIG_EVENTFD
350 qemu_set_cloexec(ret
);
351 if ((fds
[1] = dup(ret
)) == -1) {
355 qemu_set_cloexec(fds
[1]);
359 if (errno
!= ENOSYS
) {
364 return qemu_pipe(fds
);
367 int qemu_create_pidfile(const char *filename
)
373 fd
= qemu_open(filename
, O_RDWR
| O_CREAT
, 0600);
377 if (lockf(fd
, F_TLOCK
, 0) == -1) {
380 len
= snprintf(buffer
, sizeof(buffer
), "%ld\n", (long)getpid());
381 if (write(fd
, buffer
, len
) != len
) {
388 int qemu_get_thread_id(void)
390 #if defined (__linux__)
391 return syscall(SYS_gettid
);