[PATCH] trivial cleanups and change some comments

[elogind.git] / udev.c

diff --git a/udev.c b/udev.c
index 8e6d06f1bd0071a3414db5dac712a7d8b218f951..ca79bb4ec0e37812770ceaea2b76acf901d9e438 100644 (file)
--- a/udev.c
+++ b/udev.c
@@ -33,7 +33,7 @@
 
 #include "libsysfs/sysfs/libsysfs.h"
 #include "udev.h"
-#include "udev_lib.h"
+#include "udev_utils.h"
 #include "udev_sysfs.h"
 #include "udev_version.h"
 #include "namedev.h"
@@ -55,6 +55,30 @@ void log_message(int level, const char *format, ...)
 }
 #endif
 
+/* (for now) true if udevsend is the helper */
+static int manage_hotplug_event(void) {
+       char helper[256];
+       int fd;
+       int len;
+
+       fd = open("/proc/sys/kernel/hotplug", O_RDONLY);
+       if (fd < 0)
+               goto exit;
+
+       len = read(fd, helper, 256);
+       close(fd);
+
+       if (len < 0)
+               goto exit;
+       helper[len] = '\0';
+
+       if (strstr(helper, "udevsend"))
+               return 1;
+
+exit:
+       return 0;
+}
+
 static void asmlinkage sig_handler(int signum)
 {
        switch (signum) {
@@ -87,17 +111,22 @@ int main(int argc, char *argv[], char *envp[])
        act.sa_handler = (void (*) (int))sig_handler;
        sigemptyset (&act.sa_mask);
        act.sa_flags = 0;
-       /* alarm must not restart syscalls*/
        sigaction(SIGALRM, &act, NULL);
        sigaction(SIGINT, &act, NULL);
        sigaction(SIGTERM, &act, NULL);
 
-       /* trigger timeout to interrupt blocking syscalls */
+       /* trigger timeout to prevent hanging processes */
        alarm(ALARM_TIMEOUT);
 
-       udev_set_values(&udev, devpath, subsystem, action);
+       action = getenv("ACTION");
+       devpath = getenv("DEVPATH");
+       subsystem = getenv("SUBSYSTEM");
+       /* older kernels passed the SUBSYSTEM only as argument */
+       if (!subsystem && argc == 2)
+               subsystem = argv[1];
+       udev_init_device(&udev, devpath, subsystem);
 
-       if (strstr(argv[0], "udevstart") || (argv[1] != NULL && strstr(argv[1], "udevstart"))) {
+       if (strstr(argv[0], "udevstart") || (argc == 2 && strstr(argv[1], "udevstart"))) {
                dbg("udevstart");
 
                /* disable all logging, as it's much too slow on some facilities */
@@ -110,20 +139,20 @@ int main(int argc, char *argv[], char *envp[])
 
        if (!action) {
                dbg("no action");
-               goto exit;
+               goto hotplug;
        }
 
        if (!subsystem) {
                dbg("no subsystem");
-               goto exit;
+               goto hotplug;
        }
 
        if (!devpath) {
                dbg("no devpath");
-               goto exit;
+               goto hotplug;
        }
 
-       /* export logging flag, called scripts may want to do the same as udev */
+       /* export logging flag, as called scripts may want to do the same as udev */
        if (udev_log)
                setenv("UDEV_LOG", "1", 1);
 
@@ -132,17 +161,17 @@ int main(int argc, char *argv[], char *envp[])
                        /* wait for sysfs and possibly add node */
                        dbg("udev add");
 
-                       /* skip blacklisted subsystems */
+                       /* skip subsystems without "dev", but handle net devices */
                        if (udev.type != 'n' && subsystem_expect_no_dev(udev.subsystem)) {
                                dbg("don't care about '%s' devices", udev.subsystem);
-                               goto exit;
-                       };
+                               goto hotplug;
+                       }
 
                        snprintf(path, SYSFS_PATH_MAX, "%s%s", sysfs_path, udev.devpath);
                        class_dev = wait_class_device_open(path);
                        if (class_dev == NULL) {
                                dbg ("open class device failed");
-                               goto exit;
+                               goto hotplug;
                        }
                        dbg("opened class_dev->name='%s'", class_dev->name);
 
@@ -154,26 +183,25 @@ int main(int argc, char *argv[], char *envp[])
                        /* name, create node, store in db */
                        retval = udev_add_device(&udev, class_dev);
 
-                       /* run dev.d/ scripts if we created a node or changed a netif name */
-                       if (udev.devname[0] != '\0') {
-                               setenv("DEVNAME", udev.devname, 1);
-                               dev_d_execute(&udev, DEVD_DIR, DEVD_SUFFIX);
-                       }
-
                        sysfs_close_class_device(class_dev);
                } else if (strcmp(action, "remove") == 0) {
                        /* possibly remove a node */
                        dbg("udev remove");
 
-                       /* get node from db, delete it */
-                       retval = udev_remove_device(&udev);
-
-                       /* run dev.d/ scripts if we're not instructed to ignore the event */
-                       if (udev.devname[0] != '\0') {
-                               setenv("DEVNAME", udev.devname, 1);
-                               dev_d_execute(&udev, DEVD_DIR, DEVD_SUFFIX);
+                       /* skip subsystems without "dev" */
+                       if (subsystem_expect_no_dev(udev.subsystem)) {
+                               dbg("don't care about '%s' devices", udev.subsystem);
+                               goto hotplug;
                        }
 
+                       /* get node from db, remove db-entry, delete created node */
+                       retval = udev_remove_device(&udev);
+               }
+
+               /* run dev.d/ scripts if we created/deleted a node or changed a netif name */
+               if (udev_dev_d && udev.devname[0] != '\0') {
+                       setenv("DEVNAME", udev.devname, 1);
+                       udev_multiplex_directory(&udev, DEVD_DIR, DEVD_SUFFIX);
                }
        } else if ((strncmp(devpath, "/devices/", 9) == 0)) {
                if (strcmp(action, "add") == 0) {
@@ -184,7 +212,7 @@ int main(int argc, char *argv[], char *envp[])
                        devices_dev = wait_devices_device_open(path);
                        if (!devices_dev) {
                                dbg("devices device unavailable (probably remove has beaten us)");
-                               goto exit;
+                               goto hotplug;
                        }
                        dbg("devices device opened '%s'", path);
 
@@ -198,6 +226,10 @@ int main(int argc, char *argv[], char *envp[])
                dbg("unhandled");
        }
 
+hotplug:
+       if (udev_hotplug_d && manage_hotplug_event())
+               udev_multiplex_directory(&udev, HOTPLUGD_DIR, HOTPLUG_SUFFIX);
+
 exit:
        logging_close();
        return retval;