chiark / gitweb /
[PATCH] udev - trivial style cleanup
[elogind.git] / udevsend.c
index 37afaf55fa6c7a3e769e398014e682737e9903b4..0a305e50c4bf214f1dfb5b66500eee888b62ed62 100644 (file)
@@ -29,6 +29,9 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <wait.h>
 
 #include "udev.h"
 #include "udevd.h"
@@ -58,32 +61,59 @@ static inline char *get_seqnum(void)
        return seqnum;
 }
 
-static int build_hotplugmsg(struct hotplug_msg **ppmsg, char *action,
+static int build_hotplugmsg(struct hotplug_msg *msg, char *action,
                            char *devpath, char *subsystem, int seqnum)
 {
-       struct hotplug_msg *pmsg;
-
-       pmsg = malloc(sizeof(struct hotplug_msg));
-       pmsg->mtype = HOTPLUGMSGTYPE;
-       pmsg->seqnum = seqnum;
-       strncpy(pmsg->action, action, 8);
-       strncpy(pmsg->devpath, devpath, 128);
-       strncpy(pmsg->subsystem, subsystem, 16);
-       *ppmsg = pmsg;
+       memset(msg, 0x00, sizeof(msg));
+       msg->mtype = HOTPLUGMSGTYPE;
+       msg->seqnum = seqnum;
+       strncpy(msg->action, action, 8);
+       strncpy(msg->devpath, devpath, 128);
+       strncpy(msg->subsystem, subsystem, 16);
        return sizeof(struct hotplug_msg);
 }
 
-static void free_hotplugmsg(struct hotplug_msg *pmsg)
+static int start_daemon(void)
 {
-       free(pmsg);
+       pid_t pid;
+       pid_t child_pid;
+
+       pid = fork();
+       switch (pid) {
+       case 0:
+               /* helper child */
+               child_pid = fork();
+               switch (child_pid) {
+               case 0:
+                       /* daemon */
+                       setsid();
+                       chdir("/");
+                       execl(UDEVD_EXEC, "udevd", NULL);
+                       dbg("exec of daemon failed");
+                       exit(1);
+               case -1:
+                       dbg("fork of daemon failed");
+                       return -1;
+               default:
+                       exit(0);
+               }
+               break;
+       case -1:
+               dbg("fork of helper failed");
+               return -1;
+       default:
+               wait(NULL);
+       }
+       return 0;
 }
 
+
 int main(int argc, char* argv[])
 {
        int msgid;
        key_t key;
-       struct msqid_ds  msg_queue;
-       struct msgbuf *pmsg;
+       struct msqid_ds msg_queue;
+       struct hotplug_msg message;
        char *action;
        char *devpath;
        char *subsystem;
@@ -91,6 +121,8 @@ int main(int argc, char* argv[])
        int seq;
        int retval = -EINVAL;
        int size;
+       int loop;
+       struct timespec tspec;
 
        subsystem = argv[1];
        if (subsystem == NULL) {
@@ -115,38 +147,42 @@ int main(int argc, char* argv[])
                dbg("no seqnum");
                goto exit;
        }
-
        seq = atoi(seqnum);
-       key = ftok(DEFAULT_EXEC_PROGRAM, IPC_KEY_ID);
-       size =  build_hotplugmsg( (struct hotplug_msg**) &pmsg, action, devpath, subsystem, seq);
+
+       /* create ipc message queue or get id of our existing one */
+       key = ftok(UDEVD_EXEC, IPC_KEY_ID);
+       size =  build_hotplugmsg(&message, action, devpath, subsystem, seq);
        msgid = msgget(key, IPC_CREAT);
-       if (msgid == -1)
-       {
-               dbg("open ipc queue error");
+       if (msgid == -1) {
+               dbg("error open ipc queue");
                goto exit;
        }
 
-       /* get state of queue */
-       retval = msgctl(msgid, IPC_STAT, &msg_queue);
+       /* send ipc message to the daemon */
+       retval = msgsnd(msgid, &message, size, 0);
        if (retval == -1) {
-               dbg("error getting info on ipc queue");
+               dbg("error sending ipc message");
                goto exit;
        }
-       if (msg_queue.msg_qnum > 0)
-               dbg("%li messages already in the ipc queue", msg_queue.msg_qnum);
-
-       retval = msgsnd(msgid, pmsg, size, 0);
-       free_hotplugmsg( (struct hotplug_msg*) pmsg);
-       if (retval == -1)
-       {
-               dbg("send ipc message error");
-               goto exit;
+
+       /* get state of ipc queue */
+       tspec.tv_sec = 0;
+       tspec.tv_nsec = 10000000;  /* 10 millisec */
+       loop = 30;
+       while (loop--) {
+               retval = msgctl(msgid, IPC_STAT, &msg_queue);
+               if (retval == -1) {
+                       dbg("error getting info on ipc queue");
+                       goto exit;
+               }
+               if (msg_queue.msg_qnum == 0)
+                       goto exit;
+               nanosleep(&tspec, NULL);
        }
-       return 0;
 
-exit:
-       if (retval > 0)
-               retval = 0;
+       info("message is still in the ipc queue, starting daemon...");
+       retval = start_daemon();
 
+exit:
        return retval;
 }