udev: event - move renaming of udev_device to libudev

This is not exposed in the public API. We want to simplify the internal libudev-device API as much as possible
so that it will be simpler to rip the whole thing out in the future.

Signed-off-by: Anthony G. Basile <blueness@gentoo.org>

NOTES

@@ -7,11 +7,6 @@ Newest entries are on top.
 	This follows on the privious skipped commit.  Since we did not move the renaming, a
 	residual call to udev_device_set_syspath() remains in udev-event.c.
 
-	* We skip "udev: event - move renaming of udev_device to libudev"
-	http://cgit.freedesktop.org/systemd/systemd/commit/?id=243d182543c7edc3980e1ae41712bb0b96df46bd
-	The purpose of this commit is to make it easier for the kdbus cut-over later which we
-	will not do.  It also intefers with the ENABLE_RULE_GENERATOR code.
-
 2014-12-15
 
 	* We did not move builtin-hwdb - port to sd-hwdb:

src/libudev/libudev-device.c

@@ -1988,3 +1988,25 @@ struct udev_device *udev_device_new_from_nulstr(struct udev *udev, char *nulstr,
 
         return device;
 }
+
+int udev_device_rename(struct udev_device *udev_device, const char *name)
+{
+        _cleanup_free_ char *dirname = NULL;
+        char *new_syspath;
+        int r;
+
+        if (udev_device == NULL || name == NULL)
+                return -EINVAL;
+
+        dirname = dirname_malloc(udev_device->syspath);
+        if (!dirname)
+                return -ENOMEM;
+
+        new_syspath = strjoina(dirname, "/", name);
+
+        r = udev_device_set_syspath(udev_device, new_syspath);
+        if (r < 0)
+                return r;
+
+        return 0;
+}

src/libudev/libudev-private.h

@@ -45,6 +45,7 @@ uid_t udev_device_get_devnode_uid(struct udev_device *udev_device);
 gid_t udev_device_get_devnode_gid(struct udev_device *udev_device);
 int udev_device_set_subsystem(struct udev_device *udev_device, const char *subsystem);
 int udev_device_set_syspath(struct udev_device *udev_device, const char *syspath);
+int udev_device_rename(struct udev_device *udev_device, const char *new_name);
 int udev_device_set_devnum(struct udev_device *udev_device, dev_t devnum);
 int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink);
 void udev_device_cleanup_devlinks_list(struct udev_device *udev_device);

src/shared/util.c

@@ -846,6 +846,24 @@ ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll) {
         return n;
 }
 
+char* dirname_malloc(const char *path) {
+        char *d, *dir, *dir2;
+
+        d = strdup(path);
+        if (!d)
+                return NULL;
+        dir = dirname(d);
+        assert(dir);
+
+        if (dir != d) {
+                dir2 = strdup(dir);
+                free(d);
+                return dir2;
+        }
+
+        return dir;
+}
+
 int dev_urandom(void *p, size_t n) {
         static int have_syscall = -1;
         int r, fd;

src/shared/util.h

@@ -275,6 +275,9 @@ int flush_fd(int fd);
 int fopen_temporary(const char *path, FILE **_f, char **_temp_path);
 
 ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll);
+
+char* dirname_malloc(const char *path);
+
 int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid);
 
 bool null_or_empty(struct stat *st) _pure_;

src/udev/udev-event.c

@@ -862,26 +862,27 @@ void udev_event_execute_rules(struct udev_event *event,
                                           sigmask);
 
                 /* rename a new network interface, if needed */
-                int r;
                 if (udev_device_get_ifindex(dev) > 0 && streq(udev_device_get_action(dev), "add") &&
                     event->name != NULL && !streq(event->name, udev_device_get_sysname(dev))) {
-                        char syspath[UTIL_PATH_SIZE];
-                        char *pos;
-                        char *finalifname = event->name;
+                        int r;
 
                         r = rename_netif(event);
-                        if (r >= 0) {
-                                /* remember old name */
-                                udev_device_add_property(dev, "INTERFACE_OLD", udev_device_get_sysname(dev));
+                        if (r < 0)
+                                log_warning_errno(r, "could not rename interface '%d' from '%s' to '%s': %m", udev_device_get_ifindex(dev),
+                                                  udev_device_get_sysname(dev), event->name);
+                        else {
+                                const char *interface_old;
 
-                                /* now change the devpath, because the kernel device name has changed */
-                                strscpy(syspath, sizeof(syspath), udev_device_get_syspath(dev));
-                                pos = strrchr(syspath, '/');
-                                if (pos != NULL) {
-                                        pos++;
-                                        strscpy(pos, sizeof(syspath) - (pos - syspath), finalifname);
-                                        udev_device_set_syspath(event->dev, syspath);
-                                        udev_device_add_property(dev, "INTERFACE", udev_device_get_sysname(dev));
+                                /* remember old name */
+                                interface_old = udev_device_get_sysname(dev);
+
+                                r = udev_device_rename(dev, event->name);
+                                if (r < 0)
+                                        log_warning_errno(r, "renamed interface '%d' from '%s' to '%s', but could not update udev_device: %m",
+                                                          udev_device_get_ifindex(dev), udev_device_get_sysname(dev), event->name);
+                                else {
+                                        udev_device_add_property(dev, "INTERFACE_OLD", interface_old);
+                                        udev_device_add_property(dev, "INTERFACE", event->name);
                                         log_debug("changed devpath to '%s'", udev_device_get_devpath(dev));
                                 }
                         }