Imported Upstream version 1.2.0upstream/1.2.0

1 files changed, 362 insertions, 0 deletions

diff --git a/os-posix.c b/os-posix.c
new file mode 100644
index 000000000..79fa2288e
--- /dev/null
+++ b/os-posix.c
@@ -0,0 +1,362 @@
+/*
+ * 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.h"
+#include "net/slirp.h"
+#include "qemu-options.h"
+
+#ifdef CONFIG_LINUX
+#include <sys/prctl.h>
+#endif
+
+#ifdef __FreeBSD__
+#include <sys/sysctl.h>
+#endif
+
+static struct passwd *user_pwd;
+static const char *chroot_dir;
+static int daemonize;
+static int fds[2];
+
+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(const char *argv0)
+{
+    char *dir;
+    char *p = NULL;
+    char *res;
+    char buf[PATH_MAX];
+    size_t max_len;
+
+#if defined(__linux__)
+    {
+        int len;
+        len = readlink("/proc/self/exe", buf, sizeof(buf) - 1);
+        if (len > 0) {
+            buf[len] = 0;
+            p = buf;
+        }
+    }
+#elif defined(__FreeBSD__)
+    {
+        static int mib[4] = {CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1};
+        size_t len = sizeof(buf) - 1;
+
+        *buf = '\0';
+        if (!sysctl(mib, ARRAY_SIZE(mib), buf, &len, NULL, 0) &&
+            *buf) {
+            buf[sizeof(buf) - 1] = '\0';
+            p = buf;
+        }
+    }
+#endif
+    /* If we don't have any way of figuring out the actual executable
+       location then try argv[0].  */
+    if (!p) {
+        p = realpath(argv0, buf);
+        if (!p) {
+            return NULL;
+        }
+    }
+    dir = dirname(p);
+    dir = dirname(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;
+        }
+    }
+
+    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;
+    name[sizeof(name) - 1] = 0;
+    strncpy(name, s, sizeof(name));
+    /* 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
+    }
+    return;
+}
+
+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;
+
+	if (pipe(fds) == -1)
+	    exit(1);
+
+	pid = fork();
+	if (pid > 0) {
+	    uint8_t status;
+	    ssize_t len;
+
+	    close(fds[1]);
+
+	again:
+            len = read(fds[0], &status, 1);
+            if (len == -1 && (errno == EINTR))
+                goto again;
+
+            if (len != 1)
+                exit(1);
+            else if (status == 1) {
+                fprintf(stderr, "Could not acquire pidfile: %s\n", strerror(errno));
+                exit(1);
+            } else
+                exit(0);
+	} else if (pid < 0)
+            exit(1);
+
+	close(fds[0]);
+	qemu_set_cloexec(fds[1]);
+
+	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);
+    }
+}
+
+void os_setup_post(void)
+{
+    int fd = 0;
+
+    if (daemonize) {
+	uint8_t status = 0;
+	ssize_t len;
+
+    again1:
+	len = write(fds[1], &status, 1);
+	if (len == -1 && (errno == EINTR))
+	    goto again1;
+
+	if (len != 1)
+	    exit(1);
+
+        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) {
+        dup2(fd, 0);
+        dup2(fd, 1);
+        dup2(fd, 2);
+
+        close(fd);
+    }
+}
+
+void os_pidfile_error(void)
+{
+    if (daemonize) {
+        uint8_t status = 1;
+        if (write(fds[1], &status, 1) != 1) {
+            perror("daemonize. Writing to pipe\n");
+        }
+    } else
+        fprintf(stderr, "Could not acquire pid file: %s\n", strerror(errno));
+}
+
+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;
+}