* udevd.c - hotplug event serializer
*
* Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2004 Chris Friesen <chris_friesen@sympatico.ca>
*
*
* This program is free software; you can redistribute it and/or modify it
*
*/
-#include <pthread.h>
#include <stddef.h>
-#include <sys/types.h>
#include <sys/wait.h>
#include <signal.h>
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
-#include <time.h>
+#include <ctype.h>
+#include <dirent.h>
#include <fcntl.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 "list.h"
#include "udev.h"
#include "udev_version.h"
+#include "udev_utils.h"
#include "udevd.h"
#include "logging.h"
+/* global variables*/
+static int udevsendsock;
+static pid_t sid;
+
+static int pipefds[2];
+static long startup_time;
+static unsigned long long expected_seqnum = 0;
+static volatile int sigchilds_waiting;
+static volatile int run_msg_q;
+static volatile int sig_flag;
+static int run_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);
+char *udev_bin;
+
+#ifdef LOG
+void log_message (int level, const char *format, ...)
+{
+ va_list args;
-unsigned char logname[42];
-static pthread_mutex_t msg_lock;
-static pthread_mutex_t msg_active_lock;
-static pthread_cond_t msg_active;
-static pthread_mutex_t exec_lock;
-static pthread_mutex_t exec_active_lock;
-static pthread_cond_t exec_active;
-static pthread_mutex_t running_lock;
-static pthread_attr_t thr_attr;
-static int expected_seqnum = 0;
-
-LIST_HEAD(msg_list);
-LIST_HEAD(exec_list);
-LIST_HEAD(running_list);
+ va_start(args, format);
+ vsyslog(level, format, args);
+ va_end(args);
+}
+#endif
+#define msg_dump(msg) \
+ dbg("msg_dump: sequence %llu, '%s', '%s', '%s'", \
+ msg->seqnum, msg->action, msg->devpath, msg->subsystem);
static void msg_dump_queue(void)
{
+#ifdef DEBUG
struct hotplug_msg *msg;
- list_for_each_entry(msg, &msg_list, list)
- dbg("sequence %d in queue", msg->seqnum);
-}
-
-static void msg_dump(struct hotplug_msg *msg)
-{
- dbg("sequence %d, '%s', '%s', '%s'",
- msg->seqnum, msg->action, msg->devpath, msg->subsystem);
+ list_for_each_entry(msg, &msg_list, node)
+ dbg("sequence %llu in queue", msg->seqnum);
+#endif
}
-static struct hotplug_msg *msg_create(void)
+static void run_queue_delete(struct hotplug_msg *msg)
{
- struct hotplug_msg *new_msg;
-
- new_msg = malloc(sizeof(struct hotplug_msg));
- if (new_msg == NULL) {
- dbg("error malloc");
- return NULL;
- }
- return new_msg;
-}
-
-static void msg_delete(struct hotplug_msg *msg)
-{
- if (msg != NULL)
- free(msg);
+ list_del(&msg->node);
+ free(msg);
}
/* orders the message in the queue by sequence number */
static void msg_queue_insert(struct hotplug_msg *msg)
{
struct hotplug_msg *loop_msg;
+ struct sysinfo info;
+
+ if (msg->seqnum == 0) {
+ dbg("no SEQNUM, move straight to the exec queue");
+ list_add(&msg->node, &exec_list);
+ run_exec_q = 1;
+ return;
+ }
- /* sort message by sequence number into list*/
- list_for_each_entry(loop_msg, &msg_list, list)
- if (loop_msg->seqnum > msg->seqnum)
+ /* sort message by sequence number into list */
+ list_for_each_entry_reverse(loop_msg, &msg_list, node) {
+ if (loop_msg->seqnum < msg->seqnum)
break;
- list_add_tail(&msg->list, &loop_msg->list);
- dbg("queued message seq %d", msg->seqnum);
+
+ if (loop_msg->seqnum == msg->seqnum) {
+ dbg("ignoring duplicate message seq %llu", msg->seqnum);
+ return;
+ }
+ }
/* store timestamp of queuing */
- msg->queue_time = time(NULL);
+ sysinfo(&info);
+ msg->queue_time = info.uptime;
+
+ list_add(&msg->node, &loop_msg->node);
+ dbg("queued message seq %llu", msg->seqnum);
- /* signal queue activity to manager */
- pthread_mutex_lock(&msg_active_lock);
- pthread_cond_signal(&msg_active);
- pthread_mutex_unlock(&msg_active_lock);
+ /* run msg queue manager */
+ run_msg_q = 1;
- return ;
+ return;
}
/* forks event and removes event from run queue when finished */
-static void *run_threads(void * parm)
+static void udev_run(struct hotplug_msg *msg)
{
+ char *const argv[] = { "udev", msg->subsystem, NULL };
pid_t pid;
- struct hotplug_msg *msg;
-
- msg = parm;
- setenv("ACTION", msg->action, 1);
- setenv("DEVPATH", msg->devpath, 1);
pid = fork();
switch (pid) {
case 0:
/* child */
- execl(UDEV_BIN, "udev", msg->subsystem, NULL);
+ close(udevsendsock);
+ logging_close();
+
+ setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY);
+ execve(udev_bin, argv, msg->envp);
dbg("exec of child failed");
- exit(1);
+ _exit(1);
break;
case -1:
dbg("fork of child failed");
- goto exit;
+ run_queue_delete(msg);
+ break;
default:
- /* wait for exit of child */
- dbg("==> exec seq %d [%d] working at '%s'",
- msg->seqnum, pid, msg->devpath);
- wait(NULL);
- dbg("<== exec seq %d came back", msg->seqnum);
+ /* get SIGCHLD in main loop */
+ dbg("==> exec seq %llu [%d] working at '%s'", msg->seqnum, pid, msg->devpath);
+ msg->pid = pid;
}
+}
-exit:
- /* remove event from run list */
- pthread_mutex_lock(&running_lock);
- list_del_init(&msg->list);
- pthread_mutex_unlock(&running_lock);
+static int running_processes(void)
+{
+ int f;
+ static char buf[4096];
+ int len;
+ int running;
+ const char *pos;
+
+ f = open("/proc/stat", O_RDONLY);
+ if (f == -1)
+ return -1;
+
+ len = read(f, buf, sizeof(buf));
+ close(f);
+
+ if (len <= 0)
+ return -1;
+ else
+ buf[len] = '\0';
+
+ pos = strstr(buf, "procs_running ");
+ if (pos == NULL)
+ return -1;
+
+ if (sscanf(pos, "procs_running %u", &running) != 1)
+ return -1;
+
+ return running;
+}
+
+/* return the number of process es in our session, count only until limit */
+static int running_processes_in_session(pid_t session, int limit)
+{
+ DIR *dir;
+ struct dirent *dent;
+ int running = 0;
+
+ dir = opendir("/proc");
+ if (!dir)
+ return -1;
+
+ /* read process info from /proc */
+ for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+ int f;
+ char procdir[64];
+ char line[256];
+ const char *pos;
+ char state;
+ pid_t ppid, pgrp, sess;
+ int len;
+
+ if (!isdigit(dent->d_name[0]))
+ continue;
+
+ snprintf(procdir, sizeof(procdir), "/proc/%s/stat", dent->d_name);
+ procdir[sizeof(procdir)-1] = '\0';
+
+ f = open(procdir, O_RDONLY);
+ if (f == -1)
+ continue;
+
+ len = read(f, line, sizeof(line));
+ close(f);
+
+ if (len <= 0)
+ continue;
+ else
+ line[len] = '\0';
+
+ /* skip ugly program name */
+ pos = strrchr(line, ')') + 2;
+ if (pos == NULL)
+ continue;
- msg_delete(msg);
+ if (sscanf(pos, "%c %d %d %d ", &state, &ppid, &pgrp, &sess) != 4)
+ continue;
+
+ /* count only processes in our session */
+ if (sess != session)
+ continue;
- /* signal queue activity to exec manager */
- pthread_mutex_lock(&exec_active_lock);
- pthread_cond_signal(&exec_active);
- pthread_mutex_unlock(&exec_active_lock);
+ /* count only running, no sleeping processes */
+ if (state != 'R')
+ continue;
+
+ running++;
+ if (limit > 0 && running >= limit)
+ break;
+ }
+ closedir(dir);
+
+ return running;
+}
+
+static int compare_devpath(const char *running, const char *waiting)
+{
+ int i;
+
+ for (i = 0; i < DEVPATH_SIZE; i++) {
+ /* identical device event found */
+ if (running[i] == '\0' && waiting[i] == '\0')
+ return 1;
+
+ /* parent device event found */
+ if (running[i] == '\0' && waiting[i] == '/')
+ return 2;
+
+ /* child device event found */
+ if (running[i] == '/' && waiting[i] == '\0')
+ return 3;
+
+ /* no matching event */
+ if (running[i] != waiting[i])
+ break;
+ }
- pthread_exit(0);
+ return 0;
}
-/* returns already running task with devpath */
+/* returns still running task for the same device, its parent or its physical device */
static struct hotplug_msg *running_with_devpath(struct hotplug_msg *msg)
{
struct hotplug_msg *loop_msg;
- struct hotplug_msg *tmp_msg;
- list_for_each_entry_safe(loop_msg, tmp_msg, &running_list, list)
- if (strncmp(loop_msg->devpath, msg->devpath, sizeof(loop_msg->devpath)) == 0)
+ if (msg->devpath == NULL)
+ return NULL;
+
+ list_for_each_entry(loop_msg, &running_list, node) {
+ if (loop_msg->devpath == NULL)
+ continue;
+
+ /* return running parent/child device event */
+ if (compare_devpath(loop_msg->devpath, msg->devpath) != 0)
return loop_msg;
+
+ /* return running physical device event */
+ if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0)
+ if (compare_devpath(loop_msg->devpath, msg->physdevpath) != 0)
+ return loop_msg;
+ }
+
return NULL;
}
-/* queue management executes the events and delays events for the same devpath */
-static void *exec_queue_manager(void * parm)
+/* exec queue management routine executes the events and serializes events in the same sequence */
+static void exec_queue_manager(void)
{
struct hotplug_msg *loop_msg;
struct hotplug_msg *tmp_msg;
struct hotplug_msg *msg;
- pthread_t run_tid;
-
- while (1) {
- pthread_mutex_lock(&exec_lock);
- list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, list) {
- msg = running_with_devpath(loop_msg);
- if (msg == NULL) {
- /* move event to run list */
- pthread_mutex_lock(&running_lock);
- list_move_tail(&loop_msg->list, &running_list);
- pthread_mutex_unlock(&running_lock);
-
- pthread_create(&run_tid, &thr_attr, run_threads, (void *) loop_msg);
-
- dbg("moved seq %d to running list", loop_msg->seqnum);
- } else {
- dbg("delay seq %d, cause seq %d already working on '%s'",
- loop_msg->seqnum, msg->seqnum, msg->devpath);
+ int running;
+
+ running = running_processes();
+ dbg("%d processes runnning on system", running);
+ if (running < 0)
+ running = THROTTLE_MAX_RUNNING_CHILDS;
+
+ list_for_each_entry_safe(loop_msg, tmp_msg, &exec_list, node) {
+ /* check running processes in our session and possibly throttle */
+ if (running >= THROTTLE_MAX_RUNNING_CHILDS) {
+ running = running_processes_in_session(sid, THROTTLE_MAX_RUNNING_CHILDS+10);
+ dbg("%d processes running in session", running);
+ if (running >= THROTTLE_MAX_RUNNING_CHILDS) {
+ dbg("delay seq %llu, cause too many processes already running", loop_msg->seqnum);
+ return;
}
}
- pthread_mutex_unlock(&exec_lock);
- /* wait for activation, new events or childs coming back */
- pthread_mutex_lock(&exec_active_lock);
- pthread_cond_wait(&exec_active, &exec_active_lock);
- pthread_mutex_unlock(&exec_active_lock);
+ msg = running_with_devpath(loop_msg);
+ if (!msg) {
+ /* move event to run list */
+ list_move_tail(&loop_msg->node, &running_list);
+ udev_run(loop_msg);
+ running++;
+ dbg("moved seq %llu to running list", loop_msg->seqnum);
+ } else {
+ dbg("delay seq %llu (%s), cause seq %llu (%s) is still running",
+ loop_msg->seqnum, loop_msg->devpath, msg->seqnum, msg->devpath);
+ }
}
}
-static void exec_queue_activate(void)
-{
- pthread_mutex_lock(&exec_active_lock);
- pthread_cond_signal(&exec_active);
- pthread_mutex_unlock(&exec_active_lock);
-}
-
-/* move message from incoming to exec queue */
-static void msg_move_exec(struct list_head *head)
+static void msg_move_exec(struct hotplug_msg *msg)
{
- list_move_tail(head, &exec_list);
- exec_queue_activate();
+ 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);
}
-/* queue management thread handles the timeouts and dispatches the events */
-static void *msg_queue_manager(void * parm)
+/* msg queue management routine handles the timeouts and dispatches the events */
+static void msg_queue_manager(void)
{
struct hotplug_msg *loop_msg;
struct hotplug_msg *tmp_msg;
- time_t msg_age = 0;
- struct timespec tv;
+ struct sysinfo info;
+ long msg_age = 0;
+ static int timeout = EVENT_INIT_TIMEOUT_SEC;
+ static int init = 1;
- while (1) {
- dbg("msg queue manager, next expected is %d", expected_seqnum);
- pthread_mutex_lock(&msg_lock);
- pthread_mutex_lock(&exec_lock);
+ dbg("msg queue manager, next expected is %llu", expected_seqnum);
recheck:
- list_for_each_entry_safe(loop_msg, tmp_msg, &msg_list, list) {
- /* move event with expected sequence to the exec list */
- if (loop_msg->seqnum == expected_seqnum) {
- msg_move_exec(&loop_msg->list);
- expected_seqnum++;
- dbg("moved seq %d to exec, next expected is %d",
- loop_msg->seqnum, expected_seqnum);
- continue;
- }
-
- /* move event with expired timeout to the exec list */
- msg_age = time(NULL) - loop_msg->queue_time;
- if (msg_age > EVENT_TIMEOUT_SEC-1) {
- msg_move_exec(&loop_msg->list);
- expected_seqnum = loop_msg->seqnum+1;
- dbg("moved seq %d to exec, reset next expected to %d",
- loop_msg->seqnum, expected_seqnum);
- goto recheck;
- } else {
- break;
- }
+ 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;
}
- msg_dump_queue();
- pthread_mutex_unlock(&exec_lock);
- pthread_mutex_unlock(&msg_lock);
-
- /* wait until queue gets active or next message timeout expires */
- pthread_mutex_lock(&msg_active_lock);
+ /* see if we are in the initialization phase and wait for the very first events */
+ if (init && (info.uptime - startup_time >= INIT_TIME_SEC)) {
+ init = 0;
+ timeout = EVENT_TIMEOUT_SEC;
+ dbg("initialization phase passed, set timeout to %i seconds", EVENT_TIMEOUT_SEC);
+ }
- if (list_empty(&msg_list) == 0) {
- tv.tv_sec = time(NULL) + EVENT_TIMEOUT_SEC - msg_age;
- tv.tv_nsec = 0;
- dbg("next event expires in %li seconds",
- EVENT_TIMEOUT_SEC - msg_age);
- pthread_cond_timedwait(&msg_active, &msg_active_lock, &tv);
+ /* move event with expired timeout to the exec list */
+ sysinfo(&info);
+ 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 {
- pthread_cond_wait(&msg_active, &msg_active_lock);
+ break;
}
- pthread_mutex_unlock(&msg_active_lock);
+ }
+
+ msg_dump_queue();
+
+ /* set timeout for remaining queued events */
+ if (list_empty(&msg_list) == 0) {
+ struct itimerval itv = {{0, 0}, {timeout - msg_age, 0}};
+ dbg("next event expires in %li seconds", timeout - msg_age);
+ setitimer(ITIMER_REAL, &itv, NULL);
}
}
-/* every connect creates a thread which gets the msg, queues it and exits */
-static void *client_threads(void * parm)
+/* receive the udevsend message and do some sanity checks */
+static struct hotplug_msg *get_udevsend_msg(void)
{
- int sock;
+ static struct udevsend_msg usend_msg;
struct hotplug_msg *msg;
- int retval;
-
- sock = (int) parm;
+ int bufpos;
+ int i;
+ ssize_t size;
+ struct msghdr smsg;
+ struct cmsghdr *cmsg;
+ struct iovec iov;
+ struct ucred *cred;
+ char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+ int envbuf_size;
+
+ memset(&usend_msg, 0x00, sizeof(struct udevsend_msg));
+ iov.iov_base = &usend_msg;
+ iov.iov_len = sizeof(struct udevsend_msg);
+
+ memset(&smsg, 0x00, sizeof(struct msghdr));
+ smsg.msg_iov = &iov;
+ smsg.msg_iovlen = 1;
+ smsg.msg_control = cred_msg;
+ smsg.msg_controllen = sizeof(cred_msg);
+
+ size = recvmsg(udevsendsock, &smsg, 0);
+ if (size < 0) {
+ if (errno != EINTR)
+ dbg("unable to receive udevsend message");
+ return NULL;
+ }
+ cmsg = CMSG_FIRSTHDR(&smsg);
+ cred = (struct ucred *) CMSG_DATA(cmsg);
- msg = msg_create();
- if (msg == NULL) {
- dbg("unable to store message");
- goto exit;
+ if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
+ dbg("no sender credentials received, message ignored");
+ return NULL;
}
- retval = recv(sock, msg, sizeof(struct hotplug_msg), 0);
- if (retval < 0) {
- dbg("unable to receive message");
- goto exit;
+ if (cred->uid != 0) {
+ dbg("sender uid=%i, message ignored", cred->uid);
+ return NULL;
}
- if (strncmp(msg->magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
- dbg("message magic '%s' doesn't match, ignore it", msg->magic);
- msg_delete(msg);
- goto exit;
+ if (strncmp(usend_msg.magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
+ dbg("message magic '%s' doesn't match, ignore it", usend_msg.magic);
+ return NULL;
}
- /* if no seqnum is given, we move straight to exec queue */
- if (msg->seqnum == 0) {
- pthread_mutex_lock(&exec_lock);
- list_add(&msg->list, &exec_list);
- exec_queue_activate();
- pthread_mutex_unlock(&exec_lock);
- } else {
- pthread_mutex_lock(&msg_lock);
- msg_queue_insert(msg);
- pthread_mutex_unlock(&msg_lock);
+ envbuf_size = size - offsetof(struct udevsend_msg, envbuf);
+ dbg("envbuf_size=%i", envbuf_size);
+ msg = malloc(sizeof(struct hotplug_msg) + envbuf_size);
+ if (msg == NULL)
+ return NULL;
+
+ memset(msg, 0x00, sizeof(struct hotplug_msg) + envbuf_size);
+
+ /* copy environment buffer and reconstruct envp */
+ memcpy(msg->envbuf, usend_msg.envbuf, envbuf_size);
+ bufpos = 0;
+ for (i = 0; (bufpos < envbuf_size) && (i < HOTPLUG_NUM_ENVP-2); i++) {
+ int keylen;
+ char *key;
+
+ key = &msg->envbuf[bufpos];
+ keylen = strlen(key);
+ msg->envp[i] = key;
+ bufpos += keylen + 1;
+ dbg("add '%s' to msg.envp[%i]", msg->envp[i], i);
+
+ /* remember some keys for further processing */
+ if (strncmp(key, "ACTION=", 7) == 0)
+ msg->action = &key[7];
+
+ if (strncmp(key, "DEVPATH=", 8) == 0)
+ msg->devpath = &key[8];
+
+ if (strncmp(key, "SUBSYSTEM=", 10) == 0)
+ msg->subsystem = &key[10];
+
+ if (strncmp(key, "SEQNUM=", 7) == 0)
+ msg->seqnum = strtoull(&key[7], NULL, 10);
+
+ if (strncmp(key, "PHYSDEVPATH=", 12) == 0)
+ msg->physdevpath = &key[12];
}
+ msg->envp[i++] = "UDEVD_EVENT=1";
+ msg->envp[i] = NULL;
-exit:
- close(sock);
- pthread_exit(0);
+ return msg;
}
-static void sig_handler(int signum)
+static void asmlinkage sig_handler(int signum)
{
+ int rc;
+
switch (signum) {
case SIGINT:
case SIGTERM:
- unlink(UDEVD_LOCK);
exit(20 + signum);
break;
- default:
- dbg("unhandled signal");
+ 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;
}
}
-static int one_and_only(void)
+static void udev_done(int pid)
{
- char string[50];
- int lock_file;
+ /* find msg associated with pid and delete it */
+ struct hotplug_msg *msg;
- lock_file = open(UDEVD_LOCK, O_RDWR | O_CREAT, 0x640);
- if (lock_file < 0)
- return -1;
+ list_for_each_entry(msg, &running_list, node) {
+ if (msg->pid == pid) {
+ dbg("<== exec seq %llu came back", msg->seqnum);
+ run_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
+ */
+ run_exec_q = 1;
+ return;
+ }
+ }
+}
- /* see if we can lock */
- if (lockf(lock_file, F_TLOCK, 0) < 0) {
- dbg("file is already locked, exit");
- close(lock_file);
- return -1;
+static void reap_sigchilds(void)
+{
+ while(1) {
+ int pid = waitpid(-1, NULL, WNOHANG);
+ if ((pid == -1) || (pid == 0))
+ break;
+ udev_done(pid);
}
+}
- snprintf(string, sizeof(string), "%d\n", getpid());
- write(lock_file, string, strlen(string));
+/* 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;
- return 0;
+ while(1) {
+ int rc = read(pipefds[0], &sig, sizeof(sig));
+ if (rc < 0)
+ break;
+
+ sig_flag = 0;
+ }
}
-int main(int argc, char *argv[])
+static int init_udevsend_socket(void)
{
- int ssock;
- int csock;
struct sockaddr_un saddr;
- struct sockaddr_un caddr;
socklen_t addrlen;
- socklen_t clen;
- pthread_t cli_tid;
- pthread_t mgr_msg_tid;
- pthread_t mgr_exec_tid;
+ const int feature_on = 1;
int retval;
- init_logging("udevd");
-
- /* only let one version of the daemon run at any one time */
- if (one_and_only() != 0)
- exit(0);
-
- signal(SIGINT, sig_handler);
- signal(SIGTERM, sig_handler);
-
memset(&saddr, 0x00, sizeof(saddr));
saddr.sun_family = AF_LOCAL;
/* use abstract namespace for socket path */
strcpy(&saddr.sun_path[1], UDEVD_SOCK_PATH);
addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path+1) + 1;
- ssock = socket(AF_LOCAL, SOCK_STREAM, 0);
- if (ssock == -1) {
- dbg("error getting socket");
- exit(1);
+ udevsendsock = socket(AF_LOCAL, SOCK_DGRAM, 0);
+ if (udevsendsock == -1) {
+ dbg("error getting socket, %s", strerror(errno));
+ return -1;
+ }
+
+ /* the bind takes care of ensuring only one copy running */
+ retval = bind(udevsendsock, (struct sockaddr *) &saddr, addrlen);
+ if (retval < 0) {
+ dbg("bind failed, %s", strerror(errno));
+ close(udevsendsock);
+ return -1;
+ }
+
+ /* enable receiving of the sender credentials */
+ setsockopt(udevsendsock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on));
+
+ return 0;
+}
+
+int main(int argc, char *argv[], char *envp[])
+{
+ struct sysinfo info;
+ int maxsockplus;
+ int retval;
+ int fd;
+ struct sigaction act;
+ fd_set readfds;
+ const char *udevd_expected_seqnum;
+
+ logging_init("udevd");
+ dbg("version %s", UDEV_VERSION);
+
+ if (getuid() != 0) {
+ dbg("need to be root, exit");
+ goto exit;
+ }
+
+ /* daemonize on request */
+ if (argc == 2 && strcmp(argv[1], "-d") == 0) {
+ pid_t pid;
+
+ pid = fork();
+ switch (pid) {
+ case 0:
+ dbg("damonized fork running");
+ break;
+ case -1:
+ dbg("fork of daemon failed");
+ goto exit;
+ default:
+ logging_close();
+ exit(0);
+ }
+ }
+
+ /* become session leader */
+ sid = setsid();
+ dbg("our session is %d", sid);
+
+ /* make sure we don't lock any path */
+ chdir("/");
+ umask(umask(077) | 022);
+
+ /*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
+ dbg("error opening /dev/null %s", strerror(errno));
+
+ /* setup signal handler pipe */
+ retval = pipe(pipefds);
+ if (retval < 0) {
+ dbg("error getting pipes: %s", strerror(errno));
+ goto exit;
}
- retval = bind(ssock, &saddr, addrlen);
+ retval = fcntl(pipefds[0], F_SETFL, O_NONBLOCK);
if (retval < 0) {
- dbg("bind failed\n");
+ dbg("error fcntl on read pipe: %s", strerror(errno));
goto exit;
}
+ retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC);
+ if (retval < 0)
+ dbg("error fcntl on read pipe: %s", strerror(errno));
- retval = listen(ssock, SOMAXCONN);
+ retval = fcntl(pipefds[1], F_SETFL, O_NONBLOCK);
if (retval < 0) {
- dbg("listen failed\n");
+ dbg("error fcntl on write pipe: %s", strerror(errno));
goto exit;
}
+ retval = fcntl(pipefds[1], F_SETFD, FD_CLOEXEC);
+ if (retval < 0)
+ dbg("error fcntl on write pipe: %s", strerror(errno));
+
+ /* set signal handlers */
+ memset(&act, 0x00, sizeof(struct sigaction));
+ act.sa_handler = (void (*) (int))sig_handler;
+ sigemptyset(&act.sa_mask);
+ act.sa_flags = SA_RESTART;
+ sigaction(SIGINT, &act, NULL);
+ sigaction(SIGTERM, &act, NULL);
+ sigaction(SIGALRM, &act, NULL);
+ sigaction(SIGCHLD, &act, NULL);
+
+ if (init_udevsend_socket() < 0) {
+ if (errno == EADDRINUSE)
+ dbg("another udevd running, exit");
+ else
+ dbg("error initialising udevsend socket: %s", strerror(errno));
- pthread_mutex_init(&msg_lock, NULL);
- pthread_mutex_init(&msg_active_lock, NULL);
- pthread_mutex_init(&exec_lock, NULL);
- pthread_mutex_init(&exec_active_lock, NULL);
- pthread_mutex_init(&running_lock, NULL);
+ goto exit;
+ }
- /* set default attributes for created threads */
- pthread_attr_init(&thr_attr);
- pthread_attr_setdetachstate(&thr_attr, PTHREAD_CREATE_DETACHED);
- pthread_attr_setstacksize(&thr_attr, 16 * 1024);
+ /* possible override of udev binary, used for testing */
+ udev_bin = getenv("UDEV_BIN");
+ if (udev_bin != NULL)
+ dbg("udev binary is set to '%s'", udev_bin);
+ else
+ udev_bin = UDEV_BIN;
+
+ /* possible init of expected_seqnum value */
+ udevd_expected_seqnum = getenv("UDEVD_EXPECTED_SEQNUM");
+ if (udevd_expected_seqnum != NULL) {
+ expected_seqnum = strtoull(udevd_expected_seqnum, NULL, 10);
+ dbg("initialize expected_seqnum to %llu", expected_seqnum);
+ }
- /* init queue management */
- pthread_create(&mgr_msg_tid, &thr_attr, msg_queue_manager, NULL);
- pthread_create(&mgr_exec_tid, &thr_attr, exec_queue_manager, NULL);
+ /* get current time to provide shorter timeout on startup */
+ sysinfo(&info);
+ startup_time = info.uptime;
- clen = sizeof(caddr);
- /* main loop */
+ FD_ZERO(&readfds);
+ FD_SET(udevsendsock, &readfds);
+ FD_SET(pipefds[0], &readfds);
+ maxsockplus = udevsendsock+1;
while (1) {
- csock = accept(ssock, &caddr, &clen);
- if (csock < 0) {
- dbg("client accept failed\n");
+ struct hotplug_msg *msg;
+
+ fd_set workreadfds = readfds;
+ retval = select(maxsockplus, &workreadfds, NULL, NULL, NULL);
+
+ if (retval < 0) {
+ if (errno != EINTR)
+ dbg("error in select: %s", strerror(errno));
continue;
}
- pthread_create(&cli_tid, &thr_attr, client_threads, (void *) csock);
+
+ if (FD_ISSET(udevsendsock, &workreadfds)) {
+ msg = get_udevsend_msg();
+ if (msg)
+ msg_queue_insert(msg);
+ }
+
+ if (FD_ISSET(pipefds[0], &workreadfds))
+ user_sighandler();
+
+ 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;
+ exec_queue_manager();
+ }
}
+
exit:
- close(ssock);
- exit(1);
+ logging_close();
+ return 1;
}
~ianmdlvl / elogind.git / blobdiff