chiark / gitweb /
libudev: get devnum from uevent file
[elogind.git] / udev / lib / libudev-device.c
index 4a9c815064cad3478bbba11a5acba9e54ecf4bc4..359ae443dab2ec6059c66110a22e63b69dd7f60c 100644 (file)
@@ -40,7 +40,7 @@ struct udev_device {
        char *devname;
        char *subsystem;
        struct list_head link_list;
-       struct list_head env_list;
+       struct list_head properties_list;
        char *action;
        char *driver;
        char *devpath_old;
@@ -70,6 +70,8 @@ static int device_read_uevent_file(struct udev_device *udev_device)
        char filename[UTIL_PATH_SIZE];
        FILE *f;
        char line[UTIL_LINE_SIZE];
+       int maj = 0;
+       int min = 0;
 
        util_strlcpy(filename, udev_device->syspath, sizeof(filename));
        util_strlcat(filename, "/uevent", sizeof(filename));
@@ -84,9 +86,17 @@ static int device_read_uevent_file(struct udev_device *udev_device)
                if (pos == NULL)
                        continue;
                pos[0] = '\0';
+
+               if (strncmp(line, "MAJOR=", 6) == 0)
+                       maj = strtoull(&line[6], NULL, 10);
+               else if (strncmp(line, "MINOR=", 6) == 0)
+                       min = strtoull(&line[6], NULL, 10);
+
                device_add_property_from_string(udev_device, line);
        }
 
+       udev_device->devnum = makedev(maj, min);
+
        fclose(f);
        return 0;
 }
@@ -97,7 +107,6 @@ static int device_read_db(struct udev_device *udev_device)
        char filename[UTIL_PATH_SIZE];
        char line[UTIL_LINE_SIZE];
        FILE *f;
-       int rc = 0;
 
        syspath_to_db_path(udev_device, filename, sizeof(filename));
 
@@ -131,7 +140,6 @@ static int device_read_db(struct udev_device *udev_device)
        while (fgets(line, sizeof(line), f)) {
                ssize_t len;
                const char *val;
-               unsigned int maj, min;
 
                len = strlen(line);
                if (len < 4)
@@ -143,10 +151,6 @@ static int device_read_db(struct udev_device *udev_device)
                case 'N':
                        asprintf(&udev_device->devname, "%s/%s", udev_get_dev_path(udev_device->udev), val);
                        break;
-               case 'M':
-                       sscanf(val, "%u:%u", &maj, &min);
-                       device_set_devnum(udev_device, makedev(maj, min));
-                       break;
                case 'S':
                        util_strlcpy(filename, udev_get_dev_path(udev_device->udev), sizeof(filename));
                        util_strlcat(filename, "/", sizeof(filename));
@@ -157,7 +161,7 @@ static int device_read_db(struct udev_device *udev_device)
                        device_set_devlink_priority(udev_device, atoi(val));
                        break;
                case 'T':
-                       device_set_timeout(udev_device,  atoi(val));
+                       device_set_timeout(udev_device, atoi(val));
                        break;
                case 'A':
                        device_set_num_fake_partitions(udev_device, atoi(val));
@@ -172,7 +176,8 @@ static int device_read_db(struct udev_device *udev_device)
        }
        fclose(f);
 
-       return rc;
+       info(udev_device->udev, "device %p filled with udev database data\n", udev_device);
+       return 0;
 }
 
 struct udev_device *device_init(struct udev *udev)
@@ -189,7 +194,7 @@ struct udev_device *device_init(struct udev *udev)
        udev_device->refcount = 1;
        udev_device->udev = udev;
        INIT_LIST_HEAD(&udev_device->link_list);
-       INIT_LIST_HEAD(&udev_device->env_list);
+       INIT_LIST_HEAD(&udev_device->properties_list);
        INIT_LIST_HEAD(&udev_device->attr_list);
        info(udev_device->udev, "udev_device: %p created\n", udev_device);
        return udev_device;
@@ -238,8 +243,7 @@ struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char *
        info(udev, "device %p has devpath '%s'\n", udev_device, udev_device_get_devpath(udev_device));
 
        device_read_uevent_file(udev_device);
-       if (device_read_db(udev_device) >= 0)
-               info(udev, "device %p filled with udev database data\n", udev_device);
+       device_read_db(udev_device);
        return udev_device;
 }
 
@@ -247,6 +251,9 @@ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, de
 {
        char path[UTIL_PATH_SIZE];
        const char *type_str;
+       struct udev_enumerate *enumerate;
+       struct udev_list *list;
+       struct udev_device *device = NULL;
 
        if (type == 'b')
                type_str = "block";
@@ -255,12 +262,32 @@ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, de
        else
                return NULL;
 
+       /* /sys/dev/{block,char}/<maj>:<min> links */
        snprintf(path, sizeof(path), "%s/dev/%s/%u:%u", udev_get_sys_path(udev),
                 type_str, major(devnum), minor(devnum));
-       if (util_resolve_sys_link(udev, path, sizeof(path)) < 0)
-               return NULL;
+       if (util_resolve_sys_link(udev, path, sizeof(path)) == 0)
+               return udev_device_new_from_syspath(udev, path);
 
-       return udev_device_new_from_syspath(udev, path);
+       /* fallback to search all sys devices for the major/minor */
+       enumerate = udev_enumerate_new_from_subsystems(udev, NULL);
+       if (enumerate == NULL)
+               return NULL;
+       list = udev_enumerate_get_devices_list(enumerate);
+       while (list != NULL) {
+               struct udev_device *device_loop;
+
+               device_loop = udev_device_new_from_syspath(udev, udev_list_get_name(list));
+               if (device_loop != NULL) {
+                       if (udev_device_get_devnum(device_loop) == devnum) {
+                               device = device_loop;
+                               break;
+                       }
+                       udev_device_unref(device_loop);
+               }
+               list = udev_list_get_next(list);
+       }
+       udev_enumerate_unref(enumerate);
+       return device;
 }
 
 static struct udev_device *device_new_from_parent(struct udev_device *udev_device)
@@ -357,13 +384,13 @@ void udev_device_unref(struct udev_device *udev_device)
        free(udev_device->syspath);
        free(udev_device->devname);
        free(udev_device->subsystem);
-       util_name_list_cleanup(udev_device->udev, &udev_device->link_list);
-       util_name_list_cleanup(udev_device->udev, &udev_device->env_list);
+       list_cleanup(udev_device->udev, &udev_device->link_list);
+       list_cleanup(udev_device->udev, &udev_device->properties_list);
        free(udev_device->action);
        free(udev_device->driver);
        free(udev_device->devpath_old);
        free(udev_device->physdevpath);
-       util_name_list_cleanup(udev_device->udev, &udev_device->attr_list);
+       list_cleanup(udev_device->udev, &udev_device->attr_list);
        info(udev_device->udev, "udev_device: %p released\n", udev_device);
        free(udev_device);
 }
@@ -466,64 +493,38 @@ const char *udev_device_get_subsystem(struct udev_device *udev_device)
 }
 
 /**
- * udev_device_get_devlinks:
+ * udev_device_get_devlinks_list:
  * @udev_device: udev device
- * @cb: function to be called for every device link found
- * @data: data to be passed to the function
  *
- * Retrieve the device links pointing to the device file of the
- * udev device. For every device link, the passed function will be
- * called with the device link string.
- * The path is an absolute path, and starts with the device directory.
- * If the function returns 1, remaning device links will be ignored.
+ * Retrieve the list of device links pointing to the device file of
+ * the udev device. The next list entry can be retrieved with
+ * udev_list_next(), which returns #NULL if no more entries exist.
+ * The devlink path can be retrieved from the list entry by
+ * udev_list_get_name(). The path is an absolute path, and starts with
+ * the device directory.
  *
- * Returns: the number of device links passed to the caller, or a negative value on error
+ * Returns: the first entry of the device node link list
  **/
-int udev_device_get_devlinks(struct udev_device *udev_device,
-                             int (*cb)(struct udev_device *udev_device, const char *value, void *data),
-                             void *data)
+struct udev_list *udev_device_get_devlinks_list(struct udev_device *udev_device)
 {
-       struct util_name_entry *name_loop;
-       int count = 0;
-
-       if (udev_device == NULL)
-               return -1;
-       list_for_each_entry(name_loop, &udev_device->link_list, node) {
-               count++;
-               if (cb(udev_device, name_loop->name, data) != 0)
-                       break;
-       }
-       return count;
+       return list_get_entry(&udev_device->link_list);
 }
 
 /**
- * udev_device_get_properties:
+ * udev_device_get_properties_list:
  * @udev_device: udev device
- * @cb: function to be called for every property found
- * @data: data to be passed to the function
  *
- * Retrieve the property key/value pairs belonging to the
- * udev device. For every key/value pair, the passed function will be
- * called. If the function returns 1, remaning properties will be
- * ignored.
+ * Retrieve the list of key/value device properties of the udev
+ * device. The next list entry can be retrieved with udev_list_next(),
+ * which returns #NULL if no more entries exist. The property name
+ * can be retrieved from the list entry by udev_list_get_name(),
+ * the property value by udev_list_get_value().
  *
- * Returns: the number of properties passed to the caller, or a negative value on error
+ * Returns: the first entry of the property list
  **/
-int udev_device_get_properties(struct udev_device *udev_device,
-                               int (*cb)(struct udev_device *udev_device, const char *key, const char *value, void *data),
-                               void *data)
+struct udev_list *udev_device_get_properties_list(struct udev_device *udev_device)
 {
-       struct util_name_entry *name_loop;
-       int count = 0;
-
-       if (udev_device == NULL)
-               return -1;
-       list_for_each_entry(name_loop, &udev_device->env_list, node) {
-               count++;
-               if (cb(udev_device, name_loop->name, name_loop->value, data) != 0)
-                       break;
-       }
-       return count;
+       return list_get_entry(&udev_device->properties_list);
 }
 
 const char *udev_device_get_driver(struct udev_device *udev_device)
@@ -563,7 +564,7 @@ unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
 
 const char *udev_device_get_attr_value(struct udev_device *udev_device, const char *attr)
 {
-       struct util_name_entry *name_loop;
+       struct udev_list *list;
        char path[UTIL_PATH_SIZE];
        char value[UTIL_NAME_SIZE];
        struct stat statbuf;
@@ -572,11 +573,13 @@ const char *udev_device_get_attr_value(struct udev_device *udev_device, const ch
        const char *val = NULL;
 
        /* look for possibly already cached result */
-       list_for_each_entry(name_loop, &udev_device->attr_list, node) {
-               if (strcmp(name_loop->name, attr) == 0) {
-                       info(udev_device->udev, "'%s' in cache '%s'\n", attr, name_loop->value);
-                       return name_loop->value;
+       list = list_get_entry(&udev_device->attr_list);
+       while (list != NULL) {
+               if (strcmp(udev_list_get_name(list), attr) == 0) {
+                       info(udev_device->udev, "got '%s' (%s) from cache\n", attr, udev_list_get_value(list));
+                       return udev_list_get_name(list);
                }
+               list = udev_list_get_next(list);
        }
 
        util_strlcpy(path, udev_device_get_syspath(udev_device), sizeof(path));
@@ -601,7 +604,8 @@ const char *udev_device_get_attr_value(struct udev_device *udev_device, const ch
                        if (pos != NULL) {
                                pos = &pos[1];
                                info(udev_device->udev, "cache '%s' with link value '%s'\n", attr, pos);
-                               val = util_name_list_add(udev_device->udev, &udev_device->attr_list, attr, pos, 0)->value;
+                               list = list_insert(udev_device->udev, &udev_device->attr_list, attr, pos, 0);
+                               val = udev_list_get_value(list);
                        }
                }
                goto out;
@@ -632,7 +636,8 @@ const char *udev_device_get_attr_value(struct udev_device *udev_device, const ch
        value[size] = '\0';
        util_remove_trailing_chars(value, '\n');
        info(udev_device->udev, "'%s' has attribute value '%s'\n", path, value);
-       val = util_name_list_add(udev_device->udev, &udev_device->attr_list, attr, value, 0)->value;
+       list = list_insert(udev_device->udev, &udev_device->attr_list, attr, value, 0);
+       val = udev_list_get_value(list);
 out:
        return val;
 }
@@ -669,14 +674,14 @@ int device_set_devname(struct udev_device *udev_device, const char *devname)
 
 int device_add_devlink(struct udev_device *udev_device, const char *devlink)
 {
-       if (util_name_list_add(udev_device->udev, &udev_device->link_list, devlink, NULL, 0) == NULL)
+       if (list_insert(udev_device->udev, &udev_device->link_list, devlink, NULL, 0) == NULL)
                return -ENOMEM;
        return 0;
 }
 
 int device_add_property(struct udev_device *udev_device, const char *key, const char *value)
 {
-       if (util_name_list_add(udev_device->udev, &udev_device->env_list, key, value, 0) == NULL)
+       if (list_insert(udev_device->udev, &udev_device->properties_list, key, value, 0) == NULL)
                return -ENOMEM;
        return 0;
 }