chiark / gitweb /
recreate man pages from xml source
[elogind.git] / udevmonitor.c
index f4f28b1..80c4975 100644 (file)
 #include <stdlib.h>
 #include <string.h>
 #include <fcntl.h>
-#include <time.h>
 #include <errno.h>
+#include <signal.h>
+#include <sys/time.h>
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <sys/select.h>
+#include <linux/types.h>
 #include <linux/netlink.h>
-#include <asm/types.h>
 
 #include "udev.h"
 #include "udevd.h"
 
 static int uevent_netlink_sock;
 static int udev_monitor_sock;
+static volatile int udev_exit;
 
 static int init_udev_monitor_socket(void)
 {
@@ -52,15 +54,16 @@ static int init_udev_monitor_socket(void)
 
        udev_monitor_sock = socket(AF_LOCAL, SOCK_DGRAM, 0);
        if (udev_monitor_sock == -1) {
-               fprintf(stderr, "error getting socket, %s\n", strerror(errno));
+               fprintf(stderr, "error getting socket: %s\n", strerror(errno));
                return -1;
        }
 
        /* the bind takes care of ensuring only one copy running */
        retval = bind(udev_monitor_sock, (struct sockaddr *) &saddr, addrlen);
        if (retval < 0) {
-               fprintf(stderr, "bind failed, %s\n", strerror(errno));
+               fprintf(stderr, "bind failed: %s\n", strerror(errno));
                close(udev_monitor_sock);
+               udev_monitor_sock = -1;
                return -1;
        }
 
@@ -82,14 +85,14 @@ static int init_uevent_netlink_sock(void)
 
        uevent_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
        if (uevent_netlink_sock == -1) {
-               fprintf(stderr, "error getting socket, %s\n", strerror(errno));
+               fprintf(stderr, "error getting socket: %s\n", strerror(errno));
                return -1;
        }
 
        retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl,
                      sizeof(struct sockaddr_nl));
        if (retval < 0) {
-               fprintf(stderr, "bind failed, %s\n", strerror(errno));
+               fprintf(stderr, "bind failed: %s\n", strerror(errno));
                close(uevent_netlink_sock);
                uevent_netlink_sock = -1;
                return -1;
@@ -98,60 +101,103 @@ static int init_uevent_netlink_sock(void)
        return 0;
 }
 
+static void asmlinkage sig_handler(int signum)
+{
+       if (signum == SIGINT || signum == SIGTERM)
+               udev_exit = 1;
+}
+
 int main(int argc, char *argv[])
 {
+       struct sigaction act;
        int env = 0;
-       int maxsockplus;
        fd_set readfds;
-       int retval;
+       int i;
+       int retval = 0;
 
-       if (getuid() != 0) {
-               printf("need to be root, exit\n");
-               exit(1);
+       for (i = 1 ; i < argc; i++) {
+               char *arg = argv[i];
+               if (strcmp(arg, "--env") == 0 || strcmp(arg, "-e") == 0) {
+                       env = 1;
+               }
+               else if (strcmp(arg, "--help") == 0  || strcmp(arg, "-h") == 0){
+                       printf("Usage: udevmonitor [--env]\n"
+                               "  --env    print the whole event environment\n"
+                               "  --help   print this help text\n\n");
+                       exit(0);
+               } else {
+                       fprintf(stderr, "unknown option\n\n");
+                       exit(1);
+               }
        }
 
-       if (argc == 2 && strstr(argv[1], "--env"))
-               env = 1;
-
-       init_uevent_netlink_sock();
-       init_udev_monitor_socket();
-
-       FD_ZERO(&readfds);
-       FD_SET(uevent_netlink_sock, &readfds);
-       FD_SET(udev_monitor_sock, &readfds);
-       maxsockplus = udev_monitor_sock+1;
+       if (getuid() != 0) {
+               fprintf(stderr, "need to be root, exit\n\n");
+               exit(2);
+       }
 
-       while (1) {
+       /* 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);
+
+       retval = init_udev_monitor_socket();
+       if (retval)
+               goto out;
+       retval = init_uevent_netlink_sock();
+       if (retval)
+               goto out;
+
+       printf("udevmonitor prints the received event from the kernel [UEVENT]\n"
+              "and the event which udev sends out after rule processing [UDEV]\n\n");
+
+       while (!udev_exit) {
                static char buf[UEVENT_BUFFER_SIZE*2];
                ssize_t buflen;
-               fd_set workreadfds;
+               int fdcount;
+               struct timeval tv;
+               struct timezone tz;
+               char timestr[64];
 
                buflen = 0;
-               workreadfds = readfds;
-
-               retval = select(maxsockplus, &workreadfds, NULL, NULL, NULL);
-               if (retval < 0) {
+               FD_ZERO(&readfds);
+               if (uevent_netlink_sock > 0)
+                       FD_SET(uevent_netlink_sock, &readfds);
+               if (udev_monitor_sock > 0)
+                       FD_SET(udev_monitor_sock, &readfds);
+
+               fdcount = select(UDEV_MAX(uevent_netlink_sock, udev_monitor_sock)+1, &readfds, NULL, NULL, NULL);
+               if (fdcount < 0) {
                        if (errno != EINTR)
-                               fprintf(stderr, "error receiving uevent message\n");
+                               fprintf(stderr, "error receiving uevent message: %s\n", strerror(errno));
                        continue;
                }
 
-               if (FD_ISSET(uevent_netlink_sock, &workreadfds)) {
+               if (gettimeofday(&tv, &tz) == 0) {
+                       snprintf(timestr, sizeof(timestr), "%llu.%06u",
+                                (unsigned long long) tv.tv_sec, (unsigned int) tv.tv_usec);
+               } else
+                       timestr[0] = '\0';
+
+               if ((uevent_netlink_sock > 0) && FD_ISSET(uevent_netlink_sock, &readfds)) {
                        buflen = recv(uevent_netlink_sock, &buf, sizeof(buf), 0);
                        if (buflen <=  0) {
-                               fprintf(stderr, "error receiving uevent message\n");
+                               fprintf(stderr, "error receiving uevent message: %s\n", strerror(errno));
                                continue;
                        }
-                       printf("UEVENT[%i] %s\n", time(NULL), buf);
+                       printf("UEVENT[%s] %s\n", timestr, buf);
                }
 
-               if (FD_ISSET(udev_monitor_sock, &workreadfds)) {
+               if ((udev_monitor_sock > 0) && FD_ISSET(udev_monitor_sock, &readfds)) {
                        buflen = recv(udev_monitor_sock, &buf, sizeof(buf), 0);
                        if (buflen <=  0) {
-                               fprintf(stderr, "error receiving udev message\n");
+                               fprintf(stderr, "error receiving udev message: %s\n", strerror(errno));
                                continue;
                        }
-                       printf("UDEV  [%i] %s\n", time(NULL), buf);
+                       printf("UDEV  [%s] %s\n", timestr, buf);
                }
 
                if (buflen == 0)
@@ -179,7 +225,13 @@ int main(int argc, char *argv[])
                }
        }
 
-       close(uevent_netlink_sock);
-       close(udev_monitor_sock);
-       exit(1);
+out:
+       if (uevent_netlink_sock > 0)
+               close(uevent_netlink_sock);
+       if (udev_monitor_sock > 0)
+               close(udev_monitor_sock);
+
+       if (retval)
+               return 3;
+       return 0;
 }