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>
34 /* Needed early for CONFIG_BSD etc. */
35 #include "config-host.h"
37 #include "net/slirp.h"
38 #include "qemu-options.h"
40 static struct passwd *user_pwd;
41 static const char *chroot_dir;
45 void os_setup_early_signal_handling(void)
48 sigfillset(&act.sa_mask);
50 act.sa_handler = SIG_IGN;
51 sigaction(SIGPIPE, &act, NULL);
54 static void termsig_handler(int signal)
56 qemu_system_shutdown_request();
59 static void sigchld_handler(int signal)
61 waitpid(-1, NULL, WNOHANG);
64 void os_setup_signal_handling(void)
68 memset(&act, 0, sizeof(act));
69 act.sa_handler = termsig_handler;
70 sigaction(SIGINT, &act, NULL);
71 sigaction(SIGHUP, &act, NULL);
72 sigaction(SIGTERM, &act, NULL);
74 act.sa_handler = sigchld_handler;
75 act.sa_flags = SA_NOCLDSTOP;
76 sigaction(SIGCHLD, &act, NULL);
79 /* Find a likely location for support files using the location of the binary.
80 For installed binaries this will be "$bindir/../share/qemu". When
81 running from the build tree this will be "$bindir/../pc-bios". */
82 #define SHARE_SUFFIX "/share/qemu"
83 #define BUILD_SUFFIX "/pc-bios"
84 char *os_find_datadir(const char *argv0)
92 #if defined(__linux__)
95 len = readlink("/proc/self/exe", buf, sizeof(buf) - 1);
101 #elif defined(__FreeBSD__)
103 static int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
104 size_t len = sizeof(buf) - 1;
107 if (!sysctl(mib, sizeof(mib)/sizeof(*mib), buf, &len, NULL, 0) &&
109 buf[sizeof(buf) - 1] = '\0';
114 /* If we don't have any way of figuring out the actual executable
115 location then try argv[0]. */
117 p = realpath(argv0, buf);
125 max_len = strlen(dir) +
126 MAX(strlen(SHARE_SUFFIX), strlen(BUILD_SUFFIX)) + 1;
127 res = qemu_mallocz(max_len);
128 snprintf(res, max_len, "%s%s", dir, SHARE_SUFFIX);
129 if (access(res, R_OK)) {
130 snprintf(res, max_len, "%s%s", dir, BUILD_SUFFIX);
131 if (access(res, R_OK)) {
143 * Parse OS specific command line options.
144 * return 0 if option handled, -1 otherwise
146 void os_parse_cmd_args(int index, const char *optarg)
150 case QEMU_OPTION_smb:
151 if (net_slirp_smb(optarg) < 0)
155 case QEMU_OPTION_runas:
156 user_pwd = getpwnam(optarg);
158 fprintf(stderr, "User \"%s\" doesn't exist\n", optarg);
162 case QEMU_OPTION_chroot:
165 case QEMU_OPTION_daemonize:
172 static void change_process_uid(void)
175 if (setgid(user_pwd->pw_gid) < 0) {
176 fprintf(stderr, "Failed to setgid(%d)\n", user_pwd->pw_gid);
179 if (setuid(user_pwd->pw_uid) < 0) {
180 fprintf(stderr, "Failed to setuid(%d)\n", user_pwd->pw_uid);
183 if (setuid(0) != -1) {
184 fprintf(stderr, "Dropping privileges failed\n");
190 static void change_root(void)
193 if (chroot(chroot_dir) < 0) {
194 fprintf(stderr, "chroot failed\n");
198 perror("not able to chdir to /");
205 void os_daemonize(void)
221 len = read(fds[0], &status, 1);
222 if (len == -1 && (errno == EINTR))
227 else if (status == 1) {
228 fprintf(stderr, "Could not acquire pidfile: %s\n", strerror(errno));
236 qemu_set_cloexec(fds[1]);
248 signal(SIGTSTP, SIG_IGN);
249 signal(SIGTTOU, SIG_IGN);
250 signal(SIGTTIN, SIG_IGN);
254 void os_setup_post(void)
263 len = write(fds[1], &status, 1);
264 if (len == -1 && (errno == EINTR))
271 perror("not able to chdir to /");
274 TFR(fd = qemu_open("/dev/null", O_RDWR));
280 change_process_uid();
291 void os_pidfile_error(void)
295 if (write(fds[1], &status, 1) != 1) {
296 perror("daemonize. Writing to pipe\n");
299 fprintf(stderr, "Could not acquire pid file: %s\n", strerror(errno));