chiark / gitweb /
udevd: simplify udev database and fix DEVNAME handling
authorKay Sievers <kay.sievers@vrfy.org>
Sat, 11 Dec 2010 13:00:46 +0000 (14:00 +0100)
committerKay Sievers <kay.sievers@vrfy.org>
Sat, 11 Dec 2010 13:00:46 +0000 (14:00 +0100)
libudev/libudev-device-private.c
libudev/libudev-device.c
udev/udev-node.c
udev/udevadm-info.c

index 63f947e16b420a9cde1f08862d3eec9816eedfd3..bf93834c10a7353eb03980caa04aad46bd4b581b 100644 (file)
@@ -72,96 +72,83 @@ int udev_device_tag_index(struct udev_device *dev, struct udev_device *dev_old,
        return 0;
 }
 
+static bool device_has_info(struct udev_device *udev_device)
+{
+       struct udev_list_entry *list_entry;
+
+       if (udev_device_get_devlinks_list_entry(udev_device) != NULL)
+               return true;
+       if (udev_device_get_devlink_priority(udev_device) != 0)
+               return true;
+       udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device))
+               if (udev_list_entry_get_flags(list_entry))
+                       return true;
+       if (udev_device_get_tags_list_entry(udev_device) != NULL)
+               return true;
+       if (udev_device_get_watch_handle(udev_device) >= 0)
+               return true;
+       return false;
+}
+
 int udev_device_update_db(struct udev_device *udev_device)
 {
+       bool has_info;
        const char *id;
        struct udev *udev = udev_device_get_udev(udev_device);
        char filename[UTIL_PATH_SIZE];
        char filename_tmp[UTIL_PATH_SIZE];
        FILE *f;
-       char target[232]; /* on 64bit, tmpfs inlines up to 239 bytes */
        size_t devlen = strlen(udev_get_dev_path(udev))+1;
-       char *s;
-       size_t l;
-       struct udev_list_entry *list_entry;
-       int ret;
 
        id = udev_device_get_id_filename(udev_device);
        if (id == NULL)
                return -1;
+
+       has_info = device_has_info(udev_device);
        util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
-       util_strscpyl(filename_tmp, sizeof(filename_tmp), filename, ".tmp", NULL);
 
-       udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device))
-               if (udev_list_entry_get_flags(list_entry))
-                       goto file;
-       if (udev_device_get_tags_list_entry(udev_device) != NULL)
-               goto file;
-       if (udev_device_get_devlink_priority(udev_device) != 0)
-               goto file;
-       if (udev_device_get_event_timeout(udev_device) >= 0)
-               goto file;
-       if (udev_device_get_watch_handle(udev_device) >= 0)
-               goto file;
-       if (udev_device_get_devnode(udev_device) == NULL)
-               goto out;
-
-       /*
-        * if we have only the node and symlinks to store, try not to waste
-        * tmpfs memory -- store values, if they fit, in a symlink target
-        */
-       s = target;
-       l = util_strpcpy(&s, sizeof(target), &udev_device_get_devnode(udev_device)[devlen]);
-       udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(udev_device)) {
-               l = util_strpcpyl(&s, l, " ", &udev_list_entry_get_name(list_entry)[devlen], NULL);
-               if (l == 0) {
-                       info(udev, "size of links too large, create file\n");
-                       goto file;
-               }
+       /* do not store anything for otherwise empty devices */
+       if (!has_info && udev_device_get_devnode(udev_device) == NULL) {
+               unlink(filename);
+               return 0;
        }
-       udev_selinux_setfscreatecon(udev, filename_tmp, S_IFLNK);
-       util_create_path(udev, filename_tmp);
-       ret = symlink(target, filename_tmp);
-       udev_selinux_resetfscreatecon(udev);
-       if (ret != 0)
-               goto file;
-       ret = rename(filename_tmp, filename);
-       if (ret != 0)
-               goto file;
-       info(udev, "created db link (%s)\n", target);
-       goto out;
-file:
+
+       /* write a database file */
+       util_strscpyl(filename_tmp, sizeof(filename_tmp), filename, ".tmp", NULL);
        util_create_path(udev, filename_tmp);
-       f = fopen(filename_tmp, "w");
+       f = fopen(filename_tmp, "we");
        if (f == NULL) {
                err(udev, "unable to create temporary db file '%s': %m\n", filename_tmp);
                return -1;
        }
 
-       if (udev_device_get_devnode(udev_device) != NULL) {
-               fprintf(f, "N:%s\n", &udev_device_get_devnode(udev_device)[devlen]);
-               udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(udev_device))
-                       fprintf(f, "S:%s\n", &udev_list_entry_get_name(list_entry)[devlen]);
-       }
-       if (udev_device_get_devlink_priority(udev_device) != 0)
-               fprintf(f, "L:%i\n", udev_device_get_devlink_priority(udev_device));
-       if (udev_device_get_event_timeout(udev_device) >= 0)
-               fprintf(f, "T:%i\n", udev_device_get_event_timeout(udev_device));
-       if (udev_device_get_watch_handle(udev_device) >= 0)
-               fprintf(f, "W:%i\n", udev_device_get_watch_handle(udev_device));
-       udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
-               if (!udev_list_entry_get_flags(list_entry))
-                       continue;
-               fprintf(f, "E:%s=%s\n",
-                       udev_list_entry_get_name(list_entry),
-                       udev_list_entry_get_value(list_entry));
+       if (has_info) {
+               struct udev_list_entry *list_entry;
+
+               if (udev_device_get_devnode(udev_device) != NULL) {
+                       fprintf(f, "N:%s\n", &udev_device_get_devnode(udev_device)[devlen]);
+                       udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(udev_device))
+                               fprintf(f, "S:%s\n", &udev_list_entry_get_name(list_entry)[devlen]);
+               }
+               if (udev_device_get_devlink_priority(udev_device) != 0)
+                       fprintf(f, "L:%i\n", udev_device_get_devlink_priority(udev_device));
+               if (udev_device_get_watch_handle(udev_device) >= 0)
+                       fprintf(f, "W:%i\n", udev_device_get_watch_handle(udev_device));
+               udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
+                       if (!udev_list_entry_get_flags(list_entry))
+                               continue;
+                       fprintf(f, "E:%s=%s\n",
+                               udev_list_entry_get_name(list_entry),
+                               udev_list_entry_get_value(list_entry));
+               }
+               udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
+                       fprintf(f, "G:%s\n", udev_list_entry_get_name(list_entry));
        }
-       udev_list_entry_foreach(list_entry, udev_device_get_tags_list_entry(udev_device))
-               fprintf(f, "G:%s\n", udev_list_entry_get_name(list_entry));
+
        fclose(f);
        rename(filename_tmp, filename);
-       info(udev, "created db file for '%s' in '%s'\n", udev_device_get_devpath(udev_device), filename);
-out:
+       info(udev, "created %s file '%s' for '%s'\n", has_info ? "db" : "empty", 
+            filename, udev_device_get_devpath(udev_device));
        return 0;
 }
 
index d87b0c6c8ac92b87a9ef791dbc588d56577de8c1..ac206a0e16700b14c156483516957490149c69bf 100644 (file)
@@ -232,70 +232,28 @@ const char *udev_device_get_property_value(struct udev_device *udev_device, cons
 int udev_device_read_db(struct udev_device *udev_device)
 {
        const char *id;
-       struct stat stats;
        char filename[UTIL_PATH_SIZE];
        char line[UTIL_LINE_SIZE];
        FILE *f;
 
        if (udev_device->db_loaded)
                return 0;
+       udev_device->db_loaded = true;
 
        id = udev_device_get_id_filename(udev_device);
        if (id == NULL)
                return -1;
        util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/.udev/db/", id, NULL);
-
-       if (lstat(filename, &stats) != 0) {
-               dbg(udev_device->udev, "no db file to read %s: %m\n", filename);
-               return -1;
-       }
-       if ((stats.st_mode & S_IFMT) == S_IFLNK) {
-               char target[UTIL_PATH_SIZE];
-               char devnode[UTIL_PATH_SIZE];
-               int target_len;
-               char *next;
-
-               target_len = readlink(filename, target, sizeof(target));
-               if (target_len <= 0 || target_len == sizeof(target)) {
-                       info(udev_device->udev, "error reading db link %s: %m\n", filename);
-                       return -1;
-               }
-               target[target_len] = '\0';
-
-               next = strchr(target, ' ');
-               if (next != NULL) {
-                       next[0] = '\0';
-                       next = &next[1];
-               }
-               util_strscpyl(devnode, sizeof(devnode), udev_get_dev_path(udev_device->udev), "/", target, NULL);
-               udev_device_set_devnode(udev_device, devnode);
-               while (next != NULL) {
-                       char devlink[UTIL_PATH_SIZE];
-                       const char *lnk;
-
-                       lnk = next;
-                       next = strchr(next, ' ');
-                       if (next != NULL) {
-                               next[0] = '\0';
-                               next = &next[1];
-                       }
-                       util_strscpyl(devlink, sizeof(devlink), udev_get_dev_path(udev_device->udev), "/", lnk, NULL);
-                       udev_device_add_devlink(udev_device, devlink, 0);
-               }
-               info(udev_device->udev, "device %p filled with db symlink data '%s'\n", udev_device, udev_device->devnode);
-               return 0;
-       }
-
        f = fopen(filename, "re");
        if (f == NULL) {
-               dbg(udev_device->udev, "error reading db file %s: %m\n", filename);
+               info(udev_device->udev, "no db file to read %s: %m\n", filename);
                return -1;
        }
-       udev_device->db_loaded = true;
 
        while (fgets(line, sizeof(line), f)) {
                ssize_t len;
                const char *val;
+               struct udev_list_entry *entry;
 
                len = strlen(line);
                if (len < 4)
@@ -314,11 +272,9 @@ int udev_device_read_db(struct udev_device *udev_device)
                case 'L':
                        udev_device_set_devlink_priority(udev_device, atoi(val));
                        break;
-               case 'T':
-                       udev_device_set_event_timeout(udev_device, atoi(val));
-                       break;
                case 'E':
-                       udev_device_add_property_from_string(udev_device, val);
+                       entry = udev_device_add_property_from_string(udev_device, val);
+                       udev_list_entry_set_flags(entry, 1);
                        break;
                case 'G':
                        udev_device_add_tag(udev_device, val);
@@ -888,9 +844,11 @@ const char *udev_device_get_devnode(struct udev_device *udev_device)
 
        /* we might get called before we handled an event and have a db, use the kernel-provided name */
        if (udev_device->devnode == NULL && udev_device_get_knodename(udev_device) != NULL) {
-               if (asprintf(&udev_device->devnode, "%s/%s",
-                            udev_get_dev_path(udev_device->udev), udev_device_get_knodename(udev_device)) < 0)
-                       return NULL;
+               char filename[UTIL_NAME_SIZE];
+
+               util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/",
+                             udev_device_get_knodename(udev_device), NULL);
+               udev_device_set_devnode(udev_device, filename);
                return udev_device->devnode;
        }
 
@@ -1271,8 +1229,6 @@ int udev_device_set_devnode(struct udev_device *udev_device, const char *devnode
 {
        free(udev_device->devnode);
        udev_device->devnode = strdup(devnode);
-       if (devnode == NULL)
-               return 0;
        if (udev_device->devnode == NULL)
                return -ENOMEM;
        udev_device_add_property(udev_device, "DEVNAME", udev_device->devnode);
@@ -1516,7 +1472,9 @@ int udev_device_set_knodename(struct udev_device *udev_device, const char *knode
        udev_device->knodename = strdup(knodename);
        if (udev_device->knodename == NULL)
                return -ENOMEM;
-       udev_device_add_property(udev_device, "DEVNAME", udev_device->knodename);
+       /* do not overwrite the udev property with the kernel property */
+       if (udev_device->devnode == NULL)
+               udev_device_add_property(udev_device, "DEVNAME", udev_device->knodename);
        return 0;
 }
 
index 70488c420b3368974c69f7045791c70022cfb247..a9ffa988b14f0f3d66645b12d949c8e1d42979ee 100644 (file)
@@ -327,7 +327,7 @@ static void link_update(struct udev_device *dev, const char *slink, bool add)
                        err = util_create_path(udev, filename);
                        if (err != 0 && err != -ENOENT)
                                break;
-                       fd = open(filename, O_WRONLY|O_CREAT|O_NOFOLLOW, 0444);
+                       fd = open(filename, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444);
                        if (fd >= 0)
                                close(fd);
                        else
index 7206f4fcf621ed8f3c32cf35ed78d221b3b44a2e..4510f4aa907dc56a22544564ec1e10045046bf61 100644 (file)
@@ -210,38 +210,44 @@ static int convert_db(struct udev *udev)
                device = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
                if (device != NULL) {
                        const char *id;
-                       struct stat statbuf;
+                       struct stat stats;
                        char to[UTIL_PATH_SIZE];
                        char devpath[UTIL_PATH_SIZE];
                        char from[UTIL_PATH_SIZE];
 
                        id = udev_device_get_id_filename(device);
-                       if (id == NULL)
-                               goto next;
+                       if (id == NULL) {
+                               udev_device_unref(device);
+                               continue;
+                       }
                        util_strscpyl(to, sizeof(to), udev_get_dev_path(udev), "/.udev/db/", id, NULL);
 
-                       /* do not overwrite a new database file */
-                       if (lstat(to, &statbuf) == 0)
-                               goto next;
-
                        /* find old database with $subsys:$sysname */
                        util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
                                     "/.udev/db/", udev_device_get_subsystem(device), ":",
                                     udev_device_get_sysname(device), NULL);
-                       if (lstat(from, &statbuf) == 0) {
-                               rename(from, to);
-                               goto next;
+                       if (lstat(from, &stats) == 0) {
+                               if (lstat(to, &stats) == 0)
+                                       unlink(from);
+                               else
+                                       rename(from, to);
                        }
 
                        /* find old database with the encoded devpath */
                        util_path_encode(udev_device_get_devpath(device), devpath, sizeof(devpath));
                        util_strscpyl(from, sizeof(from), udev_get_dev_path(udev),
                                      "/.udev/db/", devpath, NULL);
-                       if (lstat(from, &statbuf) == 0) {
-                               rename(from, to);
-                               goto next;
+                       if (lstat(from, &stats) == 0) {
+                               if (lstat(to, &stats) == 0)
+                                       unlink(from);
+                               else
+                                       rename(from, to);
                        }
-next:
+
+                       /* read the old database, and write out a new one */
+                       udev_device_read_db(device);
+                       udev_device_update_db(device);
+
                        udev_device_unref(device);
                }
        }