chiark / gitweb /
udevd: track exit status of event process
[elogind.git] / udevd.c
diff --git a/udevd.c b/udevd.c
index 154c37058958f39c94711b73b365fce8f34edca9..b7b306131ee5e490f065a4d0a828e84bff8eeb15 100644 (file)
--- a/udevd.c
+++ b/udevd.c
 #include <dirent.h>
 #include <fcntl.h>
 #include <syslog.h>
+#include <time.h>
 #include <sys/select.h>
 #include <sys/wait.h>
-#include <sys/time.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/un.h>
-#include <sys/sysinfo.h>
 #include <sys/stat.h>
 #include <sys/ioctl.h>
 #include <linux/types.h>
@@ -52,7 +51,6 @@
 #include "udevd.h"
 #include "logging.h"
 
-/* global variables*/
 struct udev_rules rules;
 static int udevd_sock;
 static int uevent_netlink_sock;
@@ -61,19 +59,14 @@ static pid_t sid;
 
 static int signal_pipe[2] = {-1, -1};
 static volatile int sigchilds_waiting;
-static volatile int run_msg_q;
 static volatile int udev_exit;
 static volatile int reload_config;
-static int init_phase = 1;
 static int run_exec_q;
 static int stop_exec_q;
-static int event_timeout;
 static int max_childs;
 static int max_childs_running;
-static unsigned long long expected_seqnum;
 static char udev_log[32];
 
-static LIST_HEAD(msg_list);
 static LIST_HEAD(exec_list);
 static LIST_HEAD(running_list);
 
@@ -92,69 +85,6 @@ void log_message(int priority, const char *format, ...)
 }
 #endif
 
-static void msg_dump_queue(void)
-{
-#ifdef DEBUG
-       struct uevent_msg *msg;
-
-       list_for_each_entry(msg, &msg_list, node)
-               dbg("sequence %llu in queue", msg->seqnum);
-#endif
-}
-
-static void msg_queue_delete(struct uevent_msg *msg)
-{
-       list_del(&msg->node);
-       free(msg);
-}
-
-/* orders the message in the queue by sequence number */
-static void msg_queue_insert(struct uevent_msg *msg)
-{
-       struct uevent_msg *loop_msg;
-       struct sysinfo info;
-
-       if (msg->seqnum == 0) {
-               dbg("no SEQNUM, move straight to the exec queue");
-               list_add_tail(&msg->node, &exec_list);
-               run_exec_q = 1;
-               return;
-       }
-
-       /* store timestamp of queuing */
-       sysinfo(&info);
-       msg->queue_time = info.uptime;
-
-       /* with the first event we provide a phase of shorter timeout */
-       if (init_phase) {
-               static long init_time;
-
-               if (init_time == 0)
-                       init_time = info.uptime;
-               if (info.uptime - init_time >= UDEVD_INIT_TIME)
-                       init_phase = 0;
-       }
-
-       /* sort message by sequence number into list */
-       list_for_each_entry_reverse(loop_msg, &msg_list, node) {
-               if (loop_msg->seqnum < msg->seqnum)
-                       break;
-
-               if (loop_msg->seqnum == msg->seqnum) {
-                       dbg("ignoring duplicate message seq %llu", msg->seqnum);
-                       free(msg);
-                       return;
-               }
-       }
-       list_add(&msg->node, &loop_msg->node);
-       info("seq %llu queued, '%s' '%s'", msg->seqnum, msg->action, msg->devpath);
-
-       /* run msg queue manager */
-       run_msg_q = 1;
-
-       return;
-}
-
 static void asmlinkage udev_event_sig_handler(int signum)
 {
        if (signum == SIGALRM)
@@ -192,20 +122,27 @@ static int udev_event_process(struct uevent_msg *msg)
                        if (strncmp(name_loop->name, "socket:", strlen("socket:")) == 0)
                                pass_env_to_socket(&name_loop->name[strlen("socket:")], msg->devpath, msg->action);
                        else
-                               run_program(name_loop->name, udev.subsystem, NULL, 0, NULL, (udev_log_priority >= LOG_INFO));
+                               if (run_program(name_loop->name, udev.subsystem, NULL, 0, NULL,
+                                               (udev_log_priority >= LOG_INFO)))
+                                       retval = -1;
                }
        }
 
        udev_cleanup_device(&udev);
 
-       return 0;
+       return retval;
+}
+
+static void msg_queue_delete(struct uevent_msg *msg)
+{
+       list_del(&msg->node);
+       free(msg);
 }
 
-/* runs event and removes event from run queue when finished */
 static void udev_event_run(struct uevent_msg *msg)
 {
        pid_t pid;
-       struct sysinfo info;
+       int retval;
 
        pid = fork();
        switch (pid) {
@@ -221,24 +158,41 @@ static void udev_event_run(struct uevent_msg *msg)
 
                logging_init("udevd-event");
                setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
-               udev_event_process(msg);
+               retval = udev_event_process(msg);
                info("seq %llu finished", msg->seqnum);
 
                logging_close();
+               if (retval)
+                       exit(1);
                exit(0);
        case -1:
-               err("fork of child failed");
+               err("fork of child failed: %s", strerror(errno));
                msg_queue_delete(msg);
                break;
        default:
                /* get SIGCHLD in main loop */
-               sysinfo(&info);
                info("seq %llu forked, pid [%d], '%s' '%s', %ld seconds old",
-                    msg->seqnum, pid,  msg->action, msg->subsystem, info.uptime - msg->queue_time);
+                    msg->seqnum, pid,  msg->action, msg->subsystem, time(NULL) - msg->queue_time);
                msg->pid = pid;
        }
 }
 
+static void msg_queue_insert(struct uevent_msg *msg)
+{
+       msg->queue_time = time(NULL);
+
+       /* run all events with a timeout set immediately */
+       if (msg->timeout != 0) {
+               list_add_tail(&msg->node, &running_list);
+               udev_event_run(msg);
+               return;
+       }
+
+       list_add_tail(&msg->node, &exec_list);
+       run_exec_q = 1;
+}
+
+/* runs event and removes event from run queue when finished */
 static int running_processes(void)
 {
        int f;
@@ -364,20 +318,11 @@ static int running_with_devpath(struct uevent_msg *msg, int limit)
        struct uevent_msg *loop_msg;
        int childs_count = 0;
 
-       if (msg->devpath == NULL)
-               return 0;
-
-       /* skip any events with a timeout set */
-       if (msg->timeout != 0)
-               return 0;
-
        list_for_each_entry(loop_msg, &running_list, node) {
                if (limit && childs_count++ > limit) {
                        dbg("%llu, maximum number (%i) of child reached", msg->seqnum, childs_count);
                        return 1;
                }
-               if (loop_msg->devpath == NULL)
-                       continue;
 
                /* return running parent/child device event */
                if (compare_devpath(loop_msg->devpath, msg->devpath) != 0) {
@@ -399,7 +344,7 @@ static int running_with_devpath(struct uevent_msg *msg, int limit)
 }
 
 /* exec queue management routine executes the events and serializes events in the same sequence */
-static void exec_queue_manager(void)
+static void msg_queue_manager(void)
 {
        struct uevent_msg *loop_msg;
        struct uevent_msg *tmp_msg;
@@ -419,75 +364,22 @@ static void exec_queue_manager(void)
                        running = running_processes_in_session(sid, max_childs_running+10);
                        dbg("at least %d processes running in session", running);
                        if (running >= max_childs_running) {
-                               dbg("delay seq %llu, cause too many processes already running",
-                                   loop_msg->seqnum);
+                               dbg("delay seq %llu, too many processes already running", loop_msg->seqnum);
                                return;
                        }
                }
 
-               if (running_with_devpath(loop_msg, max_childs) == 0) {
-                       /* move event to run list */
-                       list_move_tail(&loop_msg->node, &running_list);
-                       udev_event_run(loop_msg);
-                       running++;
-                       dbg("moved seq %llu to running list", loop_msg->seqnum);
-               } else
+               /* don't run two processes for the same devpath and wait for the parent*/
+               if (running_with_devpath(loop_msg, max_childs)) {
                        dbg("delay seq %llu (%s)", loop_msg->seqnum, loop_msg->devpath);
-       }
-}
-
-static void msg_move_exec(struct uevent_msg *msg)
-{
-       list_move_tail(&msg->node, &exec_list);
-       run_exec_q = 1;
-       expected_seqnum = msg->seqnum+1;
-       dbg("moved seq %llu to exec, next expected is %llu",
-               msg->seqnum, expected_seqnum);
-}
-
-/* msg queue management routine handles the timeouts and dispatches the events */
-static void msg_queue_manager(void)
-{
-       struct uevent_msg *loop_msg;
-       struct uevent_msg *tmp_msg;
-       struct sysinfo info;
-       long msg_age = 0;
-       int timeout = event_timeout;
-
-       dbg("msg queue manager, next expected is %llu", expected_seqnum);
-recheck:
-       sysinfo(&info);
-       list_for_each_entry_safe(loop_msg, tmp_msg, &msg_list, node) {
-               /* move event with expected sequence to the exec list */
-               if (loop_msg->seqnum == expected_seqnum) {
-                       msg_move_exec(loop_msg);
                        continue;
                }
 
-               /* limit timeout during initialization phase */
-               if (init_phase) {
-                       if (timeout > UDEVD_INIT_EVENT_TIMEOUT)
-                               timeout = UDEVD_INIT_EVENT_TIMEOUT;
-                       dbg("initialization phase, timeout %i seconds", timeout);
-               }
-
-               /* move event with expired timeout to the exec list */
-               msg_age = info.uptime - loop_msg->queue_time;
-               dbg("seq %llu is %li seconds old", loop_msg->seqnum, msg_age);
-               if (msg_age >= timeout) {
-                       msg_move_exec(loop_msg);
-                       goto recheck;
-               } else
-                       break;
-       }
-
-       msg_dump_queue();
-
-       /* set timeout for remaining queued events */
-       if (!list_empty(&msg_list)) {
-               struct itimerval itv = {{0, 0}, {timeout - msg_age, 0}};
-               info("next event expires in %li seconds", timeout - msg_age);
-               setitimer(ITIMER_REAL, &itv, NULL);
+               /* move event to run list */
+               list_move_tail(&loop_msg->node, &running_list);
+               udev_event_run(loop_msg);
+               running++;
+               dbg("moved seq %llu to running list", loop_msg->seqnum);
        }
 }
 
@@ -539,6 +431,12 @@ static struct uevent_msg *get_msg_from_envbuf(const char *buf, int buf_size)
        msg->envp[i++] = "UDEVD_EVENT=1";
        msg->envp[i] = NULL;
 
+       if (!msg->devpath) {
+               info("DEVPATH missing, ignore message");
+               free(msg);
+               return NULL;
+       }
+
        return msg;
 }
 
@@ -569,7 +467,7 @@ static struct uevent_msg *get_udevd_msg(void)
        size = recvmsg(udevd_sock, &smsg, 0);
        if (size <  0) {
                if (errno != EINTR)
-                       err("unable to receive udevd message");
+                       err("unable to receive udevd message: %s", strerror(errno));
                return NULL;
        }
        cmsg = CMSG_FIRSTHDR(&smsg);
@@ -608,7 +506,7 @@ static struct uevent_msg *get_udevd_msg(void)
        case UDEVD_START_EXEC_QUEUE:
                info("udevd message (START_EXEC_QUEUE) received");
                stop_exec_q = 0;
-               exec_queue_manager();
+               msg_queue_manager();
                break;
        case UDEVD_SET_LOG_LEVEL:
                intval = (int *) usend_msg.envbuf;
@@ -644,7 +542,7 @@ static struct uevent_msg *get_netlink_msg(void)
        size = recv(uevent_netlink_sock, &buffer, sizeof(buffer), 0);
        if (size <  0) {
                if (errno != EINTR)
-                       err("unable to receive udevd message");
+                       err("unable to receive udevd message: %s", strerror(errno));
                return NULL;
        }
 
@@ -691,10 +589,6 @@ static void asmlinkage sig_handler(int signum)
                case SIGTERM:
                        udev_exit = 1;
                        break;
-               case SIGALRM:
-                       /* set flag, then write to pipe if needed */
-                       run_msg_q = 1;
-                       break;
                case SIGCHLD:
                        /* set flag, then write to pipe if needed */
                        sigchilds_waiting = 1;
@@ -708,25 +602,19 @@ static void asmlinkage sig_handler(int signum)
        write(signal_pipe[WRITE_END], "", 1);
 }
 
-static void udev_done(int pid)
+static void udev_done(int pid, int exitstatus)
 {
        /* find msg associated with pid and delete it */
        struct uevent_msg *msg;
-       struct sysinfo info;
 
        list_for_each_entry(msg, &running_list, node) {
                if (msg->pid == pid) {
-                       sysinfo(&info);
-                       if (msg->queue_time)
-                               info("seq %llu, pid [%d] exit, %ld seconds old", msg->seqnum, msg->pid, info.uptime - msg->queue_time);
-                       else
-                               info("seq 0, pid [%d] exit", msg->pid);
+                       info("seq %llu, pid [%d] exit with %i, %ld seconds old", msg->seqnum, msg->pid,
+                            exitstatus, time(NULL) - msg->queue_time);
+                       msg->exitstatus = exitstatus;
                        msg_queue_delete(msg);
 
-                       /* we want to run the exec queue manager since there may
-                        * be events waiting with the devpath of the one that
-                        * just finished
-                        */
+                       /* there may be events waiting with the same devpath */
                        run_exec_q = 1;
                        return;
                }
@@ -736,12 +624,17 @@ static void udev_done(int pid)
 static void reap_sigchilds(void)
 {
        pid_t pid;
+       int status;
 
        while (1) {
-               pid = waitpid(-1, NULL, WNOHANG);
+               pid = waitpid(-1, &status, WNOHANG);
                if (pid <= 0)
                        break;
-               udev_done(pid);
+               if (WIFEXITED(status))
+                       status = WEXITSTATUS(status);
+               else
+                       status = 0;
+               udev_done(pid, status);
        }
 }
 
@@ -761,7 +654,7 @@ static int init_udevd_socket(void)
 
        udevd_sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
        if (udevd_sock == -1) {
-               err("error getting socket, %s", strerror(errno));
+               err("error getting socket: %s", strerror(errno));
                return -1;
        }
 
@@ -771,7 +664,7 @@ static int init_udevd_socket(void)
        /* the bind takes care of ensuring only one copy running */
        retval = bind(udevd_sock, (struct sockaddr *) &saddr, addrlen);
        if (retval < 0) {
-               err("bind failed, %s", strerror(errno));
+               err("bind failed: %s", strerror(errno));
                return -1;
        }
 
@@ -794,7 +687,7 @@ static int init_uevent_netlink_sock(void)
 
        uevent_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
        if (uevent_netlink_sock == -1) {
-               err("error getting socket, %s", strerror(errno));
+               err("error getting socket: %s", strerror(errno));
                return -1;
        }
 
@@ -803,7 +696,7 @@ static int init_uevent_netlink_sock(void)
 
        retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl));
        if (retval < 0) {
-               err("bind failed, %s", strerror(errno));
+               err("bind failed: %s", strerror(errno));
                close(uevent_netlink_sock);
                uevent_netlink_sock = -1;
                return -1;
@@ -818,10 +711,10 @@ int main(int argc, char *argv[], char *envp[])
        struct sigaction act;
        fd_set readfds;
        const char *value;
-       int uevent_netlink_active = 0;
        int daemonize = 0;
        int i;
        int rc = 0;
+       int maxfd;
 
        /* redirect std fd's, if the kernel forks us, we don't have them at all */
        fd = open("/dev/null", O_RDWR);
@@ -838,7 +731,7 @@ int main(int argc, char *argv[], char *envp[])
 
        logging_init("udevd");
        if (fd < 0)
-               err("fatal, could not open /dev/null");
+               err("fatal, could not open /dev/null: %s", strerror(errno));
 
        udev_init_config();
        dbg("version %s", UDEV_VERSION);
@@ -864,10 +757,10 @@ int main(int argc, char *argv[], char *envp[])
        /* init sockets to receive events */
        if (init_udevd_socket() < 0) {
                if (errno == EADDRINUSE) {
-                       dbg("another udevd running, exit");
+                       err("another udevd running, exit");
                        rc = 1;
                } else {
-                       dbg("error initializing udevd socket: %s", strerror(errno));
+                       err("error initializing udevd socket: %s", strerror(errno));
                        rc = 2;
                }
                goto exit;
@@ -891,7 +784,7 @@ int main(int argc, char *argv[], char *envp[])
                        dbg("daemonized fork running");
                        break;
                case -1:
-                       err("fork of daemon failed");
+                       err("fork of daemon failed: %s", strerror(errno));
                        rc = 4;
                        goto exit;
                default:
@@ -904,7 +797,7 @@ int main(int argc, char *argv[], char *envp[])
        setpriority(PRIO_PROCESS, 0, UDEVD_PRIORITY);
 
        chdir("/");
-       umask(077);
+       umask(022);
 
        /* become session leader */
        sid = setsid();
@@ -913,7 +806,7 @@ int main(int argc, char *argv[], char *envp[])
        /* OOM_DISABLE == -17 */
        fd = open("/proc/self/oom_adj", O_RDWR);
        if (fd < 0)
-               err("error disabling OOM");
+               err("error disabling OOM: %s", strerror(errno));
        else {
                write(fd, "-17", 3);
                close(fd);
@@ -943,7 +836,6 @@ int main(int argc, char *argv[], char *envp[])
        act.sa_flags = SA_RESTART;
        sigaction(SIGINT, &act, NULL);
        sigaction(SIGTERM, &act, NULL);
-       sigaction(SIGALRM, &act, NULL);
        sigaction(SIGCHLD, &act, NULL);
        sigaction(SIGHUP, &act, NULL);
 
@@ -952,21 +844,6 @@ int main(int argc, char *argv[], char *envp[])
        if (inotify_fd > 0)
                inotify_add_watch(inotify_fd, udev_rules_filename, IN_CREATE | IN_DELETE | IN_MOVE | IN_CLOSE_WRITE);
 
-       /* init of expected_seqnum value */
-       value = getenv("UDEVD_EXPECTED_SEQNUM");
-       if (value) {
-               expected_seqnum = strtoull(value, NULL, 10);
-               info("initialize expected_seqnum to %llu", expected_seqnum);
-       }
-
-       /* timeout to wait for missing events */
-       value = getenv("UDEVD_EVENT_TIMEOUT");
-       if (value)
-               event_timeout = strtoul(value, NULL, 10);
-       else
-               event_timeout = UDEVD_EVENT_TIMEOUT;
-       info("initialize event_timeout to %u", event_timeout);
-
        /* maximum limit of forked childs */
        value = getenv("UDEVD_MAX_CHILDS");
        if (value)
@@ -990,6 +867,11 @@ int main(int argc, char *argv[], char *envp[])
        sprintf(udev_log, "UDEV_LOG=%i", udev_log_priority);
        putenv(udev_log);
 
+       maxfd = udevd_sock;
+       maxfd = UDEV_MAX(maxfd, uevent_netlink_sock);
+       maxfd = UDEV_MAX(maxfd, signal_pipe[READ_END]);
+       maxfd = UDEV_MAX(maxfd, inotify_fd);
+
        while (!udev_exit) {
                struct uevent_msg *msg;
                int fdcount;
@@ -1001,10 +883,10 @@ int main(int argc, char *argv[], char *envp[])
                if (inotify_fd > 0)
                        FD_SET(inotify_fd, &readfds);
 
-               fdcount = select(UDEV_MAX(uevent_netlink_sock, inotify_fd)+1, &readfds, NULL, NULL, NULL);
+               fdcount = select(maxfd+1, &readfds, NULL, NULL, NULL);
                if (fdcount < 0) {
                        if (errno != EINTR)
-                               dbg("error in select: %s", strerror(errno));
+                               err("error in select: %s", strerror(errno));
                        continue;
                }
 
@@ -1012,9 +894,8 @@ int main(int argc, char *argv[], char *envp[])
                if (FD_ISSET(udevd_sock, &readfds)) {
                        msg = get_udevd_msg();
                        if (msg) {
-                               /* discard kernel messages if netlink is active */
-                               if (uevent_netlink_active && msg->type == UDEVD_UEVENT_UDEVSEND && msg->seqnum != 0) {
-                                       info("skip uevent_helper message with SEQNUM, netlink is active");
+                               if (msg->type == UDEVD_UEVENT_UDEVSEND && msg->seqnum != 0) {
+                                       info("skip non-kernel message with SEQNUM");
                                        free(msg);
                                } else
                                        msg_queue_insert(msg);
@@ -1024,14 +905,8 @@ int main(int argc, char *argv[], char *envp[])
                /* get kernel netlink message */
                if (FD_ISSET(uevent_netlink_sock, &readfds)) {
                        msg = get_netlink_msg();
-                       if (msg) {
+                       if (msg)
                                msg_queue_insert(msg);
-                               /* disable udevsend with first netlink message */
-                               if (!uevent_netlink_active) {
-                                       info("uevent_nl message received, disable udevsend messages");
-                                       uevent_netlink_active = 1;
-                               }
-                       }
                }
 
                /* received a signal, clear our notification pipe */
@@ -1068,27 +943,16 @@ int main(int argc, char *argv[], char *envp[])
                        udev_rules_init(&rules, 1);
                }
 
-               /* forked child have returned */
+               /* forked child has returned */
                if (sigchilds_waiting) {
                        sigchilds_waiting = 0;
                        reap_sigchilds();
                }
 
-               if (run_msg_q) {
-                       run_msg_q = 0;
-                       msg_queue_manager();
-               }
-
                if (run_exec_q) {
-                        /* clean up running_list before calling exec_queue_manager() */
-                       if (sigchilds_waiting) {
-                               sigchilds_waiting = 0;
-                               reap_sigchilds();
-                       }
-
                        run_exec_q = 0;
                        if (!stop_exec_q)
-                               exec_queue_manager();
+                               msg_queue_manager();
                }
        }