X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udevd.c;h=3392eea1a15a44c985d34606c0edc988cf939a51;hp=110d8e7c4d3a3fe90f547f76e252dbba63f0a0e8;hb=c6303c1316e967ae2c52792b0560ee055ce4276e;hpb=cbbde2ba6c19d6515f09a2ed0955eb2808c91198 diff --git a/udevd.c b/udevd.c index 110d8e7c4..3392eea1a 100644 --- a/udevd.c +++ b/udevd.c @@ -1,5 +1,5 @@ /* - * udevd.c - hotplug event serializer + * udevd.c - event listener and serializer * * Copyright (C) 2004-2005 Kay Sievers * Copyright (C) 2004 Chris Friesen @@ -30,6 +30,7 @@ #include #include #include +#include #include #include #include @@ -38,6 +39,7 @@ #include #include #include +#include #include #include "list.h" @@ -48,37 +50,29 @@ #include "udevd.h" #include "logging.h" -#ifndef NETLINK_KOBJECT_UEVENT -#define NETLINK_KOBJECT_UEVENT 15 -#endif - /* global variables*/ static int udevd_sock; static int uevent_netlink_sock; static pid_t sid; -static int pipefds[2]; +static int signal_pipe[2] = {-1, -1}; static volatile int sigchilds_waiting; static volatile int run_msg_q; static volatile int sig_flag; +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 @@ -119,7 +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; } @@ -140,7 +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; @@ -158,7 +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; @@ -167,7 +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; @@ -192,8 +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; } } @@ -387,7 +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 @@ -443,7 +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); @@ -552,7 +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); @@ -573,6 +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; @@ -639,34 +636,23 @@ static struct uevent_msg *get_netlink_msg(void) static void asmlinkage sig_handler(int signum) { - int rc; - switch (signum) { case SIGINT: case SIGTERM: - exit(20 + signum); + udev_exit = 1; break; case SIGALRM: /* set flag, then write to pipe if needed */ run_msg_q = 1; - goto do_write; break; case SIGCHLD: /* set flag, then write to pipe if needed */ sigchilds_waiting = 1; - goto do_write; break; } -do_write: - /* if pipe is empty, write to pipe to force select to return - * immediately when it gets called - */ - if (!sig_flag) { - rc = write(pipefds[1],&signum,sizeof(signum)); - if (rc >= 0) - sig_flag = 1; - } + /* write to pipe, which will wakeup select() in our mainloop */ + write(signal_pipe[WRITE_END], "", 1); } static void udev_done(int pid) @@ -693,27 +679,13 @@ 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); } } @@ -788,9 +760,8 @@ 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; @@ -798,7 +769,23 @@ 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); @@ -818,6 +805,7 @@ int main(int argc, char *argv[], char *envp[]) stop_exec_q = 1; } } + if (daemonize) { pid_t pid; @@ -842,42 +830,29 @@ int main(int argc, char *argv[], char *envp[]) chdir("/"); umask(umask(077) | 022); - /*set a reasonable scheduling priority for the daemon */ + /* 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, 0); - dup2(fd, 1); - dup2(fd, 2); - if (fd > 2) - close(fd); - } 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)); @@ -890,10 +865,7 @@ int main(int argc, char *argv[], char *envp[]) sigaction(SIGTERM, &act, NULL); sigaction(SIGALRM, &act, NULL); sigaction(SIGCHLD, &act, NULL); - - if (init_uevent_netlink_sock() < 0) { - dbg("uevent socket not available"); - } + sigaction(SIGHUP, &act, NULL); if (init_udevd_socket() < 0) { if (errno == EADDRINUSE) @@ -904,6 +876,9 @@ 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) @@ -942,25 +917,29 @@ 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 != -1) - FD_SET(uevent_netlink_sock, &readfds); - FD_SET(pipefds[0], &readfds); - maxsockplus = udevd_sock+1; - while (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(signal_pipe[READ_END], &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; } - if (FD_ISSET(udevd_sock, &workreadfds)) { + /* get user socket message */ + if (FD_ISSET(udevd_sock, &readfds)) { msg = get_udevd_msg(); if (msg) { /* discard kernel messages if netlink is active */ @@ -973,7 +952,8 @@ int main(int argc, char *argv[], char *envp[]) } } - if (FD_ISSET(uevent_netlink_sock, &workreadfds)) { + /* get kernel netlink message */ + if ((uevent_netlink_sock > 0) && FD_ISSET(uevent_netlink_sock, &readfds)) { msg = get_netlink_msg(); if (msg) { msg_queue_insert(msg); @@ -985,9 +965,14 @@ int main(int argc, char *argv[], char *envp[]) } } - if (FD_ISSET(pipefds[0], &workreadfds)) - user_sighandler(); + /* received a signal, clear our notification pipe */ + if (FD_ISSET(signal_pipe[READ_END], &readfds)) { + char buf[256]; + read(signal_pipe[READ_END], &buf, sizeof(buf)); + } + + /* forked child have returned */ if (sigchilds_waiting) { sigchilds_waiting = 0; reap_sigchilds(); @@ -1012,6 +997,17 @@ int main(int argc, char *argv[], char *envp[]) } exit: + 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); + if (uevent_netlink_sock > 0) + close(uevent_netlink_sock); + logging_close(); - return 1; + + return 0; }