chiark / gitweb /
udevd: keep the right order for messages without SEQNUM
[elogind.git] / udevd.c
diff --git a/udevd.c b/udevd.c
index 1575da8d5a3005c217f40431091a087bc6e59407..e4880c981488a1db29112351db15d6bbf2a44d4f 100644 (file)
--- a/udevd.c
+++ b/udevd.c
@@ -30,6 +30,7 @@
 #include <ctype.h>
 #include <dirent.h>
 #include <fcntl.h>
+#include <syslog.h>
 #include <sys/select.h>
 #include <sys/wait.h>
 #include <sys/time.h>
@@ -62,21 +63,16 @@ static volatile int udev_exit;
 static int init_phase = 1;
 static int run_exec_q;
 static int stop_exec_q;
-
-static LIST_HEAD(msg_list);
-static LIST_HEAD(exec_list);
-static LIST_HEAD(running_list);
-
-static void exec_queue_manager(void);
-static void msg_queue_manager(void);
-static void user_sighandler(void);
-static void reap_sigchilds(void);
-
 static char *udev_bin;
-static unsigned long long expected_seqnum;
 static int event_timeout;
 static int max_childs;
 static int max_childs_running;
+static unsigned long long expected_seqnum;
+static char log[32];
+
+static LIST_HEAD(msg_list);
+static LIST_HEAD(exec_list);
+static LIST_HEAD(running_list);
 
 
 #ifdef USE_LOG
@@ -117,7 +113,7 @@ static void msg_queue_insert(struct uevent_msg *msg)
 
        if (msg->seqnum == 0) {
                dbg("no SEQNUM, move straight to the exec queue");
-               list_add(&msg->node, &exec_list);
+               list_add_tail(&msg->node, &exec_list);
                run_exec_q = 1;
                return;
        }
@@ -138,7 +134,8 @@ static void msg_queue_insert(struct uevent_msg *msg)
 
        /* don't delay messages with timeout set */
        if (msg->timeout) {
-               dbg("move seq %llu with timeout %u to exec queue", msg->seqnum, msg->timeout);
+               info("seq %llu with timeout %u seconds will be execute without queuing, '%s' '%s'",
+                    msg->seqnum, msg->timeout, msg->action, msg->devpath);
                list_add(&msg->node, &exec_list);
                run_exec_q = 1;
                return;
@@ -156,7 +153,7 @@ static void msg_queue_insert(struct uevent_msg *msg)
                }
        }
        list_add(&msg->node, &loop_msg->node);
-       info("seq %llu queued, devpath '%s'", msg->seqnum, msg->devpath);
+       info("seq %llu queued, '%s' '%s'", msg->seqnum, msg->action, msg->devpath);
 
        /* run msg queue manager */
        run_msg_q = 1;
@@ -165,7 +162,7 @@ static void msg_queue_insert(struct uevent_msg *msg)
 }
 
 /* forks event and removes event from run queue when finished */
-static void udev_event_fork(struct uevent_msg *msg)
+static void udev_event_run(struct uevent_msg *msg)
 {
        char *const argv[] = { "udev", msg->subsystem, NULL };
        pid_t pid;
@@ -190,8 +187,8 @@ static void udev_event_fork(struct uevent_msg *msg)
        default:
                /* get SIGCHLD in main loop */
                sysinfo(&info);
-               info("seq %llu forked, pid %d, %ld seconds old",
-                    msg->seqnum, pid, info.uptime - msg->queue_time);
+               info("seq %llu forked, pid [%d], '%s' '%s', %ld seconds old",
+                    msg->seqnum, pid,  msg->action, msg->subsystem, info.uptime - msg->queue_time);
                msg->pid = pid;
        }
 }
@@ -385,7 +382,7 @@ static void exec_queue_manager(void)
                if (running_with_devpath(loop_msg, max_childs) == 0) {
                        /* move event to run list */
                        list_move_tail(&loop_msg->node, &running_list);
-                       udev_event_fork(loop_msg);
+                       udev_event_run(loop_msg);
                        running++;
                        dbg("moved seq %llu to running list", loop_msg->seqnum);
                } else
@@ -441,7 +438,7 @@ recheck:
        msg_dump_queue();
 
        /* set timeout for remaining queued events */
-       if (list_empty(&msg_list) == 0) {
+       if (!list_empty(&msg_list)) {
                struct itimerval itv = {{0, 0}, {timeout - msg_age, 0}};
                dbg("next event expires in %li seconds", timeout - msg_age);
                setitimer(ITIMER_REAL, &itv, NULL);
@@ -550,7 +547,7 @@ static struct uevent_msg *get_udevd_msg(void)
        switch (usend_msg.type) {
        case UDEVD_UEVENT_UDEVSEND:
        case UDEVD_UEVENT_INITSEND:
-               info("udevd event message received");
+               dbg("udevd event message received");
                envbuf_size = size - offsetof(struct udevd_msg, envbuf);
                dbg("envbuf_size=%i", envbuf_size);
                msg = get_msg_from_envbuf(usend_msg.envbuf, envbuf_size);
@@ -571,6 +568,8 @@ static struct uevent_msg *get_udevd_msg(void)
                intval = (int *) usend_msg.envbuf;
                info("udevd message (SET_LOG_PRIORITY) received, udev_log_priority=%i", *intval);
                udev_log_priority = *intval;
+               sprintf(log, "UDEV_LOG=%i", udev_log_priority);
+               putenv(log);
                break;
        case UDEVD_SET_MAX_CHILDS:
                intval = (int *) usend_msg.envbuf;
@@ -658,7 +657,7 @@ static void asmlinkage sig_handler(int signum)
         * which will wakeup our mainloop
         */
        if (!sig_flag) {
-               rc = write(pipefds[1],&signum,sizeof(signum));
+               rc = write(pipefds[1], &signum, sizeof(signum));
                if (rc >= 0)
                        sig_flag = 1;
        }
@@ -688,27 +687,13 @@ static void udev_done(int pid)
 
 static void reap_sigchilds(void)
 {
-       while(1) {
-               int pid = waitpid(-1, NULL, WNOHANG);
-               if ((pid == -1) || (pid == 0))
-                       break;
-               udev_done(pid);
-       }
-}
-
-/* just read everything from the pipe and clear the flag,
- * the flags was set in the signal handler
- */
-static void user_sighandler(void)
-{
-       int sig;
+       pid_t pid;
 
-       while(1) {
-               int rc = read(pipefds[0], &sig, sizeof(sig));
-               if (rc < 0)
+       while (1) {
+               pid = waitpid(-1, NULL, WNOHANG);
+               if (pid <= 0)
                        break;
-
-               sig_flag = 0;
+               udev_done(pid);
        }
 }
 
@@ -783,9 +768,8 @@ static int init_uevent_netlink_sock(void)
 
 int main(int argc, char *argv[], char *envp[])
 {
-       int maxsockplus;
        int retval;
-       int fd;
+       int devnull;
        struct sigaction act;
        fd_set readfds;
        const char *value;
@@ -793,7 +777,23 @@ int main(int argc, char *argv[], char *envp[])
        int daemonize = 0;
        int i;
 
+       /* set std fd's to /dev/null, if the kernel forks us, we don't have them at all */
+       devnull = open("/dev/null", O_RDWR);
+       if (devnull >= 0)  {
+               if (devnull != STDIN_FILENO)
+                       dup2(devnull, STDIN_FILENO);
+               if (devnull != STDOUT_FILENO)
+                       dup2(devnull, STDOUT_FILENO);
+               if (devnull != STDERR_FILENO)
+                       dup2(devnull, STDERR_FILENO);
+               if (devnull > STDERR_FILENO)
+                       close(devnull);
+       }
+
        logging_init("udevd");
+       if (devnull < 0)
+               err("fatal, could not open /dev/null");
+
        udev_init_config();
        dbg("version %s", UDEV_VERSION);
 
@@ -813,6 +813,7 @@ int main(int argc, char *argv[], char *envp[])
                        stop_exec_q = 1;
                }
        }
+
        if (daemonize) {
                pid_t pid;
 
@@ -840,23 +841,12 @@ int main(int argc, char *argv[], char *envp[])
        /* set a reasonable scheduling priority for the daemon */
        setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
 
-       /* Set fds to dev/null */
-       fd = open( "/dev/null", O_RDWR );
-       if (fd >= 0)  {
-               dup2(fd, STDIN_FILENO);
-               dup2(fd, STDOUT_FILENO);
-               dup2(fd, STDERR_FILENO);
-               close(fd);
-       } else
-               err("error opening /dev/null %s", strerror(errno));
-
        /* setup signal handler pipe */
        retval = pipe(pipefds);
        if (retval < 0) {
                err("error getting pipes: %s", strerror(errno));
                goto exit;
        }
-
        retval = fcntl(pipefds[0], F_SETFL, O_NONBLOCK);
        if (retval < 0) {
                err("error fcntl on read pipe: %s", strerror(errno));
@@ -865,7 +855,6 @@ int main(int argc, char *argv[], char *envp[])
        retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC);
        if (retval < 0)
                err("error fcntl on read pipe: %s", strerror(errno));
-
        retval = fcntl(pipefds[1], F_SETFL, O_NONBLOCK);
        if (retval < 0) {
                err("error fcntl on write pipe: %s", strerror(errno));
@@ -886,10 +875,6 @@ int main(int argc, char *argv[], char *envp[])
        sigaction(SIGCHLD, &act, NULL);
        sigaction(SIGHUP, &act, NULL);
 
-       if (init_uevent_netlink_sock() < 0) {
-               dbg("uevent socket not available");
-       }
-
        if (init_udevd_socket() < 0) {
                if (errno == EADDRINUSE)
                        dbg("another udevd running, exit");
@@ -899,6 +884,9 @@ int main(int argc, char *argv[], char *envp[])
                goto exit;
        }
 
+       if (init_uevent_netlink_sock() < 0)
+               info("uevent socket not available");
+
        /* override of forked udev binary, used for testing */
        udev_bin = getenv("UDEV_BIN");
        if (udev_bin != NULL)
@@ -937,26 +925,29 @@ int main(int argc, char *argv[], char *envp[])
                max_childs_running = UDEVD_MAX_CHILDS_RUNNING;
        info("initialize max_childs_running to %u", max_childs_running);
 
-       FD_ZERO(&readfds);
-       FD_SET(udevd_sock, &readfds);
-       if (uevent_netlink_sock > 0)
-               FD_SET(uevent_netlink_sock, &readfds);
-       FD_SET(pipefds[0], &readfds);
-       maxsockplus = udevd_sock+1;
+       /* export log_priority , as called programs may want to follow that setting */
+       sprintf(log, "UDEV_LOG=%i", udev_log_priority);
+       putenv(log);
+
        while (!udev_exit) {
                struct uevent_msg *msg;
+               int fdcount;
 
-               fd_set workreadfds = readfds;
-               retval = select(maxsockplus, &workreadfds, NULL, NULL, NULL);
+               FD_ZERO(&readfds);
+               FD_SET(pipefds[0], &readfds);
+               FD_SET(udevd_sock, &readfds);
+               if (uevent_netlink_sock > 0)
+                       FD_SET(uevent_netlink_sock, &readfds);
 
-               if (retval < 0) {
+               fdcount = select(UDEV_MAX(udevd_sock, uevent_netlink_sock)+1, &readfds, NULL, NULL, NULL);
+               if (fdcount < 0) {
                        if (errno != EINTR)
                                dbg("error in select: %s", strerror(errno));
                        continue;
                }
 
                /* get user socket message */
-               if (FD_ISSET(udevd_sock, &workreadfds)) {
+               if (FD_ISSET(udevd_sock, &readfds)) {
                        msg = get_udevd_msg();
                        if (msg) {
                                /* discard kernel messages if netlink is active */
@@ -970,7 +961,7 @@ int main(int argc, char *argv[], char *envp[])
                }
 
                /* get kernel netlink message */
-               if (FD_ISSET(uevent_netlink_sock, &workreadfds)) {
+               if ((uevent_netlink_sock > 0) && FD_ISSET(uevent_netlink_sock, &readfds)) {
                        msg = get_netlink_msg();
                        if (msg) {
                                msg_queue_insert(msg);
@@ -983,8 +974,17 @@ int main(int argc, char *argv[], char *envp[])
                }
 
                /* received a signal, clear our notification pipe */
-               if (FD_ISSET(pipefds[0], &workreadfds))
-                       user_sighandler();
+               if (FD_ISSET(pipefds[0], &readfds)) {
+                       int sig;
+                       ssize_t rlen;
+
+                       while(1) {
+                               rlen = read(pipefds[0], &sig, sizeof(sig));
+                               if (rlen <= 0)
+                                       break;
+                       }
+                       sig_flag = 0;
+               }
 
                /* forked child have returned */
                if (sigchilds_waiting) {
@@ -1018,7 +1018,6 @@ exit:
 
        if (udevd_sock > 0)
                close(udevd_sock);
-
        if (uevent_netlink_sock > 0)
                close(uevent_netlink_sock);