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-rw-r--r--src/os-posix.c336
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diff --git a/src/os-posix.c b/src/os-posix.c
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+/*
+ * os-posix.c
+ *
+ * Copyright (c) 2003-2008 Fabrice Bellard
+ * Copyright (c) 2010 Red Hat, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <unistd.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+/*needed for MAP_POPULATE before including qemu-options.h */
+#include <sys/mman.h>
+#include <pwd.h>
+#include <grp.h>
+#include <libgen.h>
+
+/* Needed early for CONFIG_BSD etc. */
+#include "config-host.h"
+#include "sysemu/sysemu.h"
+#include "net/slirp.h"
+#include "qemu-options.h"
+#include "qemu/rcu.h"
+
+#ifdef CONFIG_LINUX
+#include <sys/prctl.h>
+#endif
+
+static struct passwd *user_pwd;
+static const char *chroot_dir;
+static int daemonize;
+static int daemon_pipe;
+
+void os_setup_early_signal_handling(void)
+{
+ struct sigaction act;
+ sigfillset(&act.sa_mask);
+ act.sa_flags = 0;
+ act.sa_handler = SIG_IGN;
+ sigaction(SIGPIPE, &act, NULL);
+}
+
+static void termsig_handler(int signal, siginfo_t *info, void *c)
+{
+ qemu_system_killed(info->si_signo, info->si_pid);
+}
+
+void os_setup_signal_handling(void)
+{
+ struct sigaction act;
+
+ memset(&act, 0, sizeof(act));
+ act.sa_sigaction = termsig_handler;
+ act.sa_flags = SA_SIGINFO;
+ sigaction(SIGINT, &act, NULL);
+ sigaction(SIGHUP, &act, NULL);
+ sigaction(SIGTERM, &act, NULL);
+}
+
+/* Find a likely location for support files using the location of the binary.
+ For installed binaries this will be "$bindir/../share/qemu". When
+ running from the build tree this will be "$bindir/../pc-bios". */
+#define SHARE_SUFFIX "/share/qemu"
+#define BUILD_SUFFIX "/pc-bios"
+char *os_find_datadir(void)
+{
+ char *dir, *exec_dir;
+ char *res;
+ size_t max_len;
+
+ exec_dir = qemu_get_exec_dir();
+ if (exec_dir == NULL) {
+ return NULL;
+ }
+ dir = dirname(exec_dir);
+
+ max_len = strlen(dir) +
+ MAX(strlen(SHARE_SUFFIX), strlen(BUILD_SUFFIX)) + 1;
+ res = g_malloc0(max_len);
+ snprintf(res, max_len, "%s%s", dir, SHARE_SUFFIX);
+ if (access(res, R_OK)) {
+ snprintf(res, max_len, "%s%s", dir, BUILD_SUFFIX);
+ if (access(res, R_OK)) {
+ g_free(res);
+ res = NULL;
+ }
+ }
+
+ g_free(exec_dir);
+ return res;
+}
+#undef SHARE_SUFFIX
+#undef BUILD_SUFFIX
+
+void os_set_proc_name(const char *s)
+{
+#if defined(PR_SET_NAME)
+ char name[16];
+ if (!s)
+ return;
+ pstrcpy(name, sizeof(name), s);
+ /* Could rewrite argv[0] too, but that's a bit more complicated.
+ This simple way is enough for `top'. */
+ if (prctl(PR_SET_NAME, name)) {
+ perror("unable to change process name");
+ exit(1);
+ }
+#else
+ fprintf(stderr, "Change of process name not supported by your OS\n");
+ exit(1);
+#endif
+}
+
+/*
+ * Parse OS specific command line options.
+ * return 0 if option handled, -1 otherwise
+ */
+void os_parse_cmd_args(int index, const char *optarg)
+{
+ switch (index) {
+#ifdef CONFIG_SLIRP
+ case QEMU_OPTION_smb:
+ if (net_slirp_smb(optarg) < 0)
+ exit(1);
+ break;
+#endif
+ case QEMU_OPTION_runas:
+ user_pwd = getpwnam(optarg);
+ if (!user_pwd) {
+ fprintf(stderr, "User \"%s\" doesn't exist\n", optarg);
+ exit(1);
+ }
+ break;
+ case QEMU_OPTION_chroot:
+ chroot_dir = optarg;
+ break;
+ case QEMU_OPTION_daemonize:
+ daemonize = 1;
+ break;
+#if defined(CONFIG_LINUX)
+ case QEMU_OPTION_enablefips:
+ fips_set_state(true);
+ break;
+#endif
+ }
+}
+
+static void change_process_uid(void)
+{
+ if (user_pwd) {
+ if (setgid(user_pwd->pw_gid) < 0) {
+ fprintf(stderr, "Failed to setgid(%d)\n", user_pwd->pw_gid);
+ exit(1);
+ }
+ if (initgroups(user_pwd->pw_name, user_pwd->pw_gid) < 0) {
+ fprintf(stderr, "Failed to initgroups(\"%s\", %d)\n",
+ user_pwd->pw_name, user_pwd->pw_gid);
+ exit(1);
+ }
+ if (setuid(user_pwd->pw_uid) < 0) {
+ fprintf(stderr, "Failed to setuid(%d)\n", user_pwd->pw_uid);
+ exit(1);
+ }
+ if (setuid(0) != -1) {
+ fprintf(stderr, "Dropping privileges failed\n");
+ exit(1);
+ }
+ }
+}
+
+static void change_root(void)
+{
+ if (chroot_dir) {
+ if (chroot(chroot_dir) < 0) {
+ fprintf(stderr, "chroot failed\n");
+ exit(1);
+ }
+ if (chdir("/")) {
+ perror("not able to chdir to /");
+ exit(1);
+ }
+ }
+
+}
+
+void os_daemonize(void)
+{
+ if (daemonize) {
+ pid_t pid;
+ int fds[2];
+
+ if (pipe(fds) == -1) {
+ exit(1);
+ }
+
+ pid = fork();
+ if (pid > 0) {
+ uint8_t status;
+ ssize_t len;
+
+ close(fds[1]);
+
+ do {
+ len = read(fds[0], &status, 1);
+ } while (len < 0 && errno == EINTR);
+
+ /* only exit successfully if our child actually wrote
+ * a one-byte zero to our pipe, upon successful init */
+ exit(len == 1 && status == 0 ? 0 : 1);
+
+ } else if (pid < 0) {
+ exit(1);
+ }
+
+ close(fds[0]);
+ daemon_pipe = fds[1];
+ qemu_set_cloexec(daemon_pipe);
+
+ setsid();
+
+ pid = fork();
+ if (pid > 0) {
+ exit(0);
+ } else if (pid < 0) {
+ exit(1);
+ }
+ umask(027);
+
+ signal(SIGTSTP, SIG_IGN);
+ signal(SIGTTOU, SIG_IGN);
+ signal(SIGTTIN, SIG_IGN);
+ rcu_after_fork();
+ }
+}
+
+void os_setup_post(void)
+{
+ int fd = 0;
+
+ if (daemonize) {
+ if (chdir("/")) {
+ perror("not able to chdir to /");
+ exit(1);
+ }
+ TFR(fd = qemu_open("/dev/null", O_RDWR));
+ if (fd == -1) {
+ exit(1);
+ }
+ }
+
+ change_root();
+ change_process_uid();
+
+ if (daemonize) {
+ uint8_t status = 0;
+ ssize_t len;
+
+ dup2(fd, 0);
+ dup2(fd, 1);
+ dup2(fd, 2);
+
+ close(fd);
+
+ do {
+ len = write(daemon_pipe, &status, 1);
+ } while (len < 0 && errno == EINTR);
+ if (len != 1) {
+ exit(1);
+ }
+ }
+}
+
+void os_set_line_buffering(void)
+{
+ setvbuf(stdout, NULL, _IOLBF, 0);
+}
+
+int qemu_create_pidfile(const char *filename)
+{
+ char buffer[128];
+ int len;
+ int fd;
+
+ fd = qemu_open(filename, O_RDWR | O_CREAT, 0600);
+ if (fd == -1) {
+ return -1;
+ }
+ if (lockf(fd, F_TLOCK, 0) == -1) {
+ close(fd);
+ return -1;
+ }
+ len = snprintf(buffer, sizeof(buffer), FMT_pid "\n", getpid());
+ if (write(fd, buffer, len) != len) {
+ close(fd);
+ return -1;
+ }
+
+ /* keep pidfile open & locked forever */
+ return 0;
+}
+
+bool is_daemonized(void)
+{
+ return daemonize;
+}
+
+int os_mlock(void)
+{
+ int ret = 0;
+
+ ret = mlockall(MCL_CURRENT | MCL_FUTURE);
+ if (ret < 0) {
+ perror("mlockall");
+ }
+
+ return ret;
+}
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