chiark / gitweb /
[PATCH] don't call dev.d/ scripts twice, if directory = subsystem
[elogind.git] / udev.c
diff --git a/udev.c b/udev.c
index 67b86e5..5ad7e42 100644 (file)
--- a/udev.c
+++ b/udev.c
@@ -3,8 +3,8 @@
  *
  * Userspace devfs
  *
- * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
- *
+ * Copyright (C) 2003,2004 Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
  *
  *     This program is free software; you can redistribute it and/or modify it
  *     under the terms of the GNU General Public License as published by the
  *
  */
 
+#include <stdio.h>
+#include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
-#include <stdio.h>
 #include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
 #include <ctype.h>
+#include <errno.h>
+#include <signal.h>
+#include <unistd.h>
 
+#include "libsysfs/sysfs/libsysfs.h"
 #include "udev.h"
+#include "udev_utils.h"
+#include "udev_sysfs.h"
 #include "udev_version.h"
 #include "namedev.h"
-#include "udevdb.h"
-#include "libsysfs/libsysfs.h"
+#include "logging.h"
 
-/* global variables */
-char **main_argv;
-char **main_envp;
 
-static inline char *get_action(void)
+#ifdef LOG
+unsigned char logname[LOGNAME_SIZE];
+void log_message(int level, const char *format, ...)
 {
-       char *action;
-
-       action = getenv("ACTION");
-       return action;
-}
+       va_list args;
 
-static inline char *get_devpath(void)
-{
-       char *devpath;
+       if (!udev_log)
+               return;
 
-       devpath = getenv("DEVPATH");
-       return devpath;
+       va_start(args, format);
+       vsyslog(level, format, args);
+       va_end(args);
 }
+#endif
 
-static inline char *get_seqnum(void)
-{
-       char *seqnum;
+/* (for now) true if udevsend is the helper */
+static int manage_hotplug_event(void) {
+       char helper[256];
+       int fd;
+       int len;
 
-       seqnum = getenv("SEQNUM");
-       return seqnum;
-}
+       fd = open("/proc/sys/kernel/hotplug", O_RDONLY);
+       if (fd < 0)
+               goto exit;
 
-#ifdef USE_DBUS
+       len = read(fd, helper, 256);
+       close(fd);
 
-/** Global variable for the connection the to system message bus or #NULL
- *  if we cannot connect or acquire the org.kernel.udev service
- */
-DBusConnection* sysbus_connection;
+       if (len < 0)
+               goto exit;
+       helper[len] = '\0';
 
-/** Disconnect from the system message bus */
-static void sysbus_disconnect()
-{
-        if (sysbus_connection == NULL)
-                return;
+       if (strstr(helper, "udevsend"))
+               return 1;
 
-        dbus_connection_disconnect(sysbus_connection);
-        sysbus_connection = NULL;
+exit:
+       return 0;
 }
 
-/** Connect to the system message bus */
-static void sysbus_connect()
+static void asmlinkage sig_handler(int signum)
 {
-        DBusError error;
-
-        /* Connect to a well-known bus instance, the system bus */
-        dbus_error_init(&error);
-        sysbus_connection = dbus_bus_get(DBUS_BUS_SYSTEM, &error);
-        if (sysbus_connection == NULL) {
-                dbg("cannot connect to system message bus, error %s: %s", 
-                    error.name, error.message);
-                dbus_error_free(&error);
-                return;
-        }
-
-        /*  Acquire the org.kernel.udev service such that listeners
-         *  know that the message is really from us and not from a
-         *  random attacker. See the file udev_sysbus_policy.conf for
-         *  details.
-         *
-         *  Note that a service can have multiple owners (though there
-         *  is a concept of a primary owner for reception of messages)
-         *  so no race is introduced if two copies of udev is running
-         *  at the same time.
-         */
-        dbus_bus_acquire_service(sysbus_connection, "org.kernel.udev", 0, 
-                                 &error);
-        if (dbus_error_is_set(&error)) {
-                printf("cannot acquire org.kernel.udev service, error %s: %s'",
-                       error.name, error.message);
-                sysbus_disconnect();
-                return;
-        }
+       switch (signum) {
+               case SIGALRM:
+                       exit(1);
+               case SIGINT:
+               case SIGTERM:
+                       exit(20 + signum);
+       }
 }
 
-#endif /* USE_DBUS */
-
-int main(int argc, char **argv, char **envp)
+int main(int argc, char *argv[], char *envp[])
 {
-       char *action;
-       char *devpath;
-       char *subsystem;
+       struct sigaction act;
+       struct sysfs_class_device *class_dev;
+       struct sysfs_device *devices_dev;
+       struct udevice udev;
+       char path[SYSFS_PATH_MAX];
        int retval = -EINVAL;
-       
-       main_argv = argv;
-       main_envp = envp;
+       const char *error;
+       const char *action = getenv("ACTION");
+       const char *devpath = getenv("DEVPATH");
+       const char *subsystem = argv[1];
 
        dbg("version %s", UDEV_VERSION);
+       logging_init("udev");
+       udev_init_config();
 
-       if (argc != 2) {
-               dbg ("unknown number of arguments");
-               goto exit;
-       }
+       /* set signal handlers */
+       memset(&act, 0x00, sizeof(act));
+       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);
 
-       subsystem = argv[1];
+       /* trigger timeout to interrupt blocking syscalls */
+       alarm(ALARM_TIMEOUT);
 
-       devpath = get_devpath();
-       if (!devpath) {
-               dbg ("no devpath?");
-               goto exit;
-       }
-       dbg("looking at '%s'", devpath);
+       udev_set_values(&udev, devpath, subsystem, action);
 
-       /* we only care about class devices and block stuff */
-       if (!strstr(devpath, "class") &&
-           !strstr(devpath, "block")) {
-               dbg("not a block or class device");
-               goto exit;
-       }
+       if (strstr(argv[0], "udevstart") || (argv[1] != NULL && strstr(argv[1], "udevstart"))) {
+               dbg("udevstart");
+
+               /* disable all logging, as it's much too slow on some facilities */
+               udev_log = 0;
 
-       /* but we don't care about net class devices */
-       if (strcmp(subsystem, "net") == 0) {
-               dbg("don't care about net devices");
+               namedev_init();
+               retval = udev_start();
                goto exit;
        }
 
-       action = get_action();
        if (!action) {
-               dbg ("no action?");
-               goto exit;
+               dbg("no action");
+               goto hotplug;
        }
 
-       /* initialize our configuration */
-       udev_init_config();
-
-#ifdef USE_DBUS
-        /* connect to the system message bus */
-        sysbus_connect();
-#endif /* USE_DBUS */
-
-       /* initialize udev database */
-       retval = udevdb_init(UDEVDB_DEFAULT);
-       if (retval != 0) {
-               dbg("unable to initialize database");
-               goto exit;
+       if (!subsystem) {
+               dbg("no subsystem");
+               goto hotplug;
        }
 
-       /* initialize the naming deamon */
-       namedev_init();
-
-       if (strcmp(action, "add") == 0)
-               retval = udev_add_device(devpath, subsystem);
-
-       else if (strcmp(action, "remove") == 0)
-               retval = udev_remove_device(devpath, subsystem);
+       if (!devpath) {
+               dbg("no devpath");
+               goto hotplug;
+       }
 
-       else {
-               dbg("unknown action '%s'", action);
-               retval = -EINVAL;
+       /* export logging flag, as called scripts may want to do the same as udev */
+       if (udev_log)
+               setenv("UDEV_LOG", "1", 1);
+
+       if ((strncmp(devpath, "/block/", 7) == 0) || (strncmp(devpath, "/class/", 7) == 0)) {
+               if (strcmp(action, "add") == 0) {
+                       /* wait for sysfs and possibly add node */
+                       dbg("udev add");
+
+                       /* skip blacklisted subsystems */
+                       if (udev.type != 'n' && subsystem_expect_no_dev(udev.subsystem)) {
+                               dbg("don't care about '%s' devices", udev.subsystem);
+                               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 hotplug;
+                       }
+                       dbg("opened class_dev->name='%s'", class_dev->name);
+
+                       wait_for_class_device(class_dev, &error);
+
+                       /* init rules, permissions */
+                       namedev_init();
+
+                       /* 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_dev_d && udev.devname[0] != '\0') {
+                               setenv("DEVNAME", udev.devname, 1);
+                               udev_multiplex_directory(&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, remove db-entry, delete created node */
+                       retval = udev_remove_device(&udev);
+
+                       /* Set the DEVNAME if known */
+                       if (udev.devname[0] != '\0') {
+                               setenv("DEVNAME", udev.devname, 1);
+                       }
+                       /* run dev.d/ scripts if we're not instructed to ignore the event */
+                       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) {
+                       /* wait for sysfs */
+                       dbg("devices add");
+
+                       snprintf(path, SYSFS_PATH_MAX, "%s%s", sysfs_path, devpath);
+                       devices_dev = wait_devices_device_open(path);
+                       if (!devices_dev) {
+                               dbg("devices device unavailable (probably remove has beaten us)");
+                               goto hotplug;
+                       }
+                       dbg("devices device opened '%s'", path);
+
+                       wait_for_devices_device(devices_dev, &error);
+
+                       sysfs_close_device(devices_dev);
+               } else if (strcmp(action, "remove") == 0) {
+                       dbg("devices remove");
+               }
+       } else {
+               dbg("unhandled");
        }
-       udevdb_exit();
 
-#ifdef USE_DBUS
-        /* disconnect from the system message bus */
-        sysbus_disconnect();
-#endif /* USE_DBUS */
+hotplug:
+       if (manage_hotplug_event())
+               udev_multiplex_directory(&udev, HOTPLUGD_DIR, HOTPLUG_SUFFIX);
 
-exit:  
+exit:
+       logging_close();
        return retval;
 }