use WRITE_END/READ_END for the pipe index

[elogind.git] / udevd.c

diff --git a/udevd.c b/udevd.c
index 79d3e825501a51ae1de3967da0277893091b061d..d26d53fe0b79d8b9fb61f97e61d186d85ee9d0d8 100644 (file)
--- a/udevd.c
+++ b/udevd.c
@@ -55,7 +55,7 @@ static int udevd_sock;
 static int uevent_netlink_sock;
 static pid_t sid;
 
-static int pipefds[2] = {-1, -1};
+static int signal_pipe[2] = {-1, -1};
 static volatile int sigchilds_waiting;
 static volatile int run_msg_q;
 static volatile int sig_flag;
@@ -113,7 +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;
        }
@@ -657,7 +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(signal_pipe[1], &signum, sizeof(signum));
                if (rc >= 0)
                        sig_flag = 1;
        }
@@ -777,7 +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);
 
@@ -825,36 +841,26 @@ 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 */
-       devnull = open( "/dev/null", O_RDWR );
-       if (devnull > 0)  {
-               dup2(devnull, STDIN_FILENO);
-               dup2(devnull, STDOUT_FILENO);
-               dup2(devnull, STDERR_FILENO);
-               close(devnull);
-       } else
-               err("error opening /dev/null %s", strerror(errno));
-
        /* setup signal handler pipe */
-       retval = pipe(pipefds);
+       retval = pipe(signal_pipe);
        if (retval < 0) {
                err("error getting pipes: %s", strerror(errno));
                goto exit;
        }
-       retval = fcntl(pipefds[0], F_SETFL, O_NONBLOCK);
+       retval = fcntl(signal_pipe[READ_END], F_SETFL, O_NONBLOCK);
        if (retval < 0) {
                err("error fcntl on read pipe: %s", strerror(errno));
                goto exit;
        }
-       retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC);
+       retval = fcntl(signal_pipe[READ_END], F_SETFD, FD_CLOEXEC);
        if (retval < 0)
                err("error fcntl on read pipe: %s", strerror(errno));
-       retval = fcntl(pipefds[1], F_SETFL, O_NONBLOCK);
+       retval = fcntl(signal_pipe[WRITE_END], F_SETFL, O_NONBLOCK);
        if (retval < 0) {
                err("error fcntl on write pipe: %s", strerror(errno));
                goto exit;
        }
-       retval = fcntl(pipefds[1], F_SETFD, FD_CLOEXEC);
+       retval = fcntl(signal_pipe[WRITE_END], F_SETFD, FD_CLOEXEC);
        if (retval < 0)
                err("error fcntl on write pipe: %s", strerror(errno));
 
@@ -928,7 +934,7 @@ int main(int argc, char *argv[], char *envp[])
                int fdcount;
 
                FD_ZERO(&readfds);
-               FD_SET(pipefds[0], &readfds);
+               FD_SET(signal_pipe[READ_END], &readfds);
                FD_SET(udevd_sock, &readfds);
                if (uevent_netlink_sock > 0)
                        FD_SET(uevent_netlink_sock, &readfds);
@@ -968,12 +974,12 @@ int main(int argc, char *argv[], char *envp[])
                }
 
                /* received a signal, clear our notification pipe */
-               if (FD_ISSET(pipefds[0], &readfds)) {
+               if (FD_ISSET(signal_pipe[0], &readfds)) {
                        int sig;
                        ssize_t rlen;
 
                        while(1) {
-                               rlen = read(pipefds[0], &sig, sizeof(sig));
+                               rlen = read(signal_pipe[0], &sig, sizeof(sig));
                                if (rlen <= 0)
                                        break;
                        }
@@ -1005,10 +1011,10 @@ int main(int argc, char *argv[], char *envp[])
        }
 
 exit:
-       if (pipefds[0] > 0)
-               close(pipefds[0]);
-       if (pipefds[1] > 0)
-               close(pipefds[1]);
+       if (signal_pipe[READ_END] > 0)
+               close(signal_pipe[READ_END]);
+       if (signal_pipe[WRITE_END] > 0)
+               close(signal_pipe[WRITE_END]);
 
        if (udevd_sock > 0)
                close(udevd_sock);