#include "libudev.h"
#include "libudev-private.h"
+/**
+ * SECTION:libudev-device
+ * @short_description: kernel sys devices
+ *
+ * Representation of kernel sys devices. Devices are uniquely identified
+ * by their syspath, every device has exactly one path in the kernel sys
+ * filesystem. Devices usually belong to a kernel subsystem, and and have
+ * a unique name inside that subsystem.
+ */
+
+/**
+ * udev_device:
+ *
+ * Opaque object representing one kernel sys device.
+ */
struct udev_device {
struct udev *udev;
struct udev_device *parent_device;
char *driver;
char *action;
char *devpath_old;
+ char *sysname_old;
char *knodename;
char **envp;
char *monitor_buf;
unsigned int ignore_remove:1;
};
-static size_t devpath_to_db_path(struct udev *udev, const char *devpath, char *filename, size_t len)
-{
- char *s;
- size_t l;
-
- s = filename;
- l = util_strpcpyl(&s, len, udev_get_dev_path(udev), "/.udev/db/", NULL);
- return util_path_encode(devpath, s, l);
-}
-
int udev_device_read_db(struct udev_device *udev_device)
{
struct stat stats;
char line[UTIL_LINE_SIZE];
FILE *f;
- devpath_to_db_path(udev_device->udev, udev_device->devpath, filename, sizeof(filename));
+ util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/.udev/db/",
+ udev_device_get_subsystem(udev_device), ":", udev_device_get_sysname(udev_device), NULL);
if (lstat(filename, &stats) != 0) {
dbg(udev_device->udev, "no db file to read %s: %m\n", filename);
next = &next[1];
}
util_strscpyl(devlink, sizeof(devlink), udev_get_dev_path(udev_device->udev), "/", lnk, NULL);
- udev_device_add_devlink(udev_device, devlink);
+ 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;
break;
case 'S':
util_strscpyl(filename, sizeof(filename), udev_get_dev_path(udev_device->udev), "/", val, NULL);
- udev_device_add_devlink(udev_device, filename);
+ udev_device_add_devlink(udev_device, filename, 0);
break;
case 'L':
udev_device_set_devlink_priority(udev_device, atoi(val));
* @syspath: sys device path including sys directory
*
* Create new udev device, and fill in information from the sys
- * device and the udev database entry. The sypath is the absolute
+ * device and the udev database entry. The syspath is the absolute
* path to the device, including the sys mount point.
*
* The initial refcount is 1, and needs to be decremented to
util_strscpy(path, sizeof(path), syspath);
util_resolve_sys_link(udev, path, sizeof(path));
- /* try to resolve the silly block layout if needed */
- if (strncmp(&path[len], "/block/", 7) == 0) {
- char block[UTIL_PATH_SIZE];
- char part[UTIL_PATH_SIZE];
-
- util_strscpy(block, sizeof(block), path);
- pos = strrchr(block, '/');
- if (pos == NULL)
- return NULL;
- util_strscpy(part, sizeof(part), pos);
- pos[0] = '\0';
- if (util_resolve_sys_link(udev, block, sizeof(block)) == 0)
- util_strscpyl(path, sizeof(path), block, part, NULL);
- }
-
- /* path exists in sys */
- if (strncmp(&syspath[len], "/devices/", 9) == 0 ||
- strncmp(&syspath[len], "/class/", 7) == 0 ||
- strncmp(&syspath[len], "/block/", 7) == 0) {
+ if (strncmp(&syspath[len], "/devices/", 9) == 0) {
char file[UTIL_PATH_SIZE];
/* all "devices" require a "uevent" file */
return udev_device;
}
+/**
+ * udev_device_new_from_devnum:
+ * @udev: udev library context
+ * @type: char or block device
+ * @devnum: device major/minor number
+ *
+ * Create new udev device, and fill in information from the sys
+ * device and the udev database entry. The device is looked up
+ * by its major/minor number. Character and block device numbers
+ * are not unique across the two types, they do not share the same
+ * range of numbers.
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, if it does not exist
+ **/
struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, dev_t devnum)
{
char path[UTIL_PATH_SIZE];
const char *type_str;
- struct udev_enumerate *udev_enumerate;
- struct udev_list_entry *list_entry;
- struct udev_device *device = NULL;
if (type == 'b')
type_str = "block";
else
return NULL;
- /* /sys/dev/{block,char}/<maj>:<min> link */
- 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 udev_device_new_from_syspath(udev, path);
-
- udev_enumerate = udev_enumerate_new(udev);
- if (udev_enumerate == NULL)
- return NULL;
-
- /* fallback to search sys devices for the major/minor */
- if (type == 'b')
- udev_enumerate_add_match_subsystem(udev_enumerate, "block");
- else if (type == 'c')
- udev_enumerate_add_nomatch_subsystem(udev_enumerate, "block");
- udev_enumerate_scan_devices(udev_enumerate);
- udev_list_entry_foreach(list_entry, udev_enumerate_get_list_entry(udev_enumerate)) {
- struct udev_device *device_loop;
-
- device_loop = udev_device_new_from_syspath(udev, udev_list_entry_get_name(list_entry));
- if (device_loop != NULL) {
- if (udev_device_get_devnum(device_loop) == devnum) {
- if (type == 'b' && strcmp(udev_device_get_subsystem(device_loop), "block") != 0)
- continue;
- if (type == 'c' && strcmp(udev_device_get_subsystem(device_loop), "block") == 0)
- continue;
- device = device_loop;
- break;
- }
- udev_device_unref(device_loop);
- }
- }
- udev_enumerate_unref(udev_enumerate);
- return device;
+ /* use /sys/dev/{block,char}/<maj>:<min> link */
+ snprintf(path, sizeof(path), "%s/dev/%s/%u:%u",
+ udev_get_sys_path(udev), type_str, major(devnum), minor(devnum));
+ return udev_device_new_from_syspath(udev, path);
}
+/**
+ * udev_device_new_from_subsystem_sysname:
+ * @udev: udev library context
+ * @subsystem: the subsystem of the device
+ * @sysname: the name of the device
+ *
+ * Create new udev device, and fill in information from the sys
+ * device and the udev database entry. The device is looked up
+ * by the subsystem and name string of the device, like "mem",
+ * "zero", or "block", "sda".
+ *
+ * The initial refcount is 1, and needs to be decremented to
+ * release the resources of the udev device.
+ *
+ * Returns: a new udev device, or #NULL, if it does not exist
+ **/
struct udev_device *udev_device_new_from_subsystem_sysname(struct udev *udev, const char *subsystem, const char *sysname)
{
char path_full[UTIL_PATH_SIZE];
char path[UTIL_PATH_SIZE];
const char *subdir;
- /* follow "device" link in deprecated sys layout */
- if (strncmp(udev_device->devpath, "/class/", 7) == 0 ||
- strncmp(udev_device->devpath, "/block/", 7) == 0) {
- util_strscpyl(path, sizeof(path), udev_device->syspath, "/device", NULL);
- if (util_resolve_sys_link(udev_device->udev, path, sizeof(path)) == 0) {
- udev_device_parent = udev_device_new_from_syspath(udev_device->udev, path);
- if (udev_device_parent != NULL)
- return udev_device_parent;
- }
- }
-
util_strscpy(path, sizeof(path), udev_device->syspath);
subdir = &path[strlen(udev_get_sys_path(udev_device->udev))+1];
- while (1) {
+ for (;;) {
char *pos;
pos = strrchr(subdir, '/');
return NULL;
}
+/**
+ * udev_device_get_parent:
+ * @udev_device: the device to start searching from
+ *
+ * Find the next parent device, and fill in information from the sys
+ * device and the udev database entry.
+ *
+ * The returned the device is not referenced. It is attached to the
+ * child device, and will be cleaned up when the child device
+ * is cleaned up.
+ *
+ * It is not necessarily just the upper level directory, empty or not
+ * recognized sys directories are ignored.
+ *
+ * It can be called as many times as needed, without caring about
+ * references.
+ *
+ * Returns: a new udev device, or #NULL, if it no parent exist.
+ **/
struct udev_device *udev_device_get_parent(struct udev_device *udev_device)
{
if (udev_device == NULL)
return udev_device->parent_device;
}
+/**
+ * udev_device_get_parent_with_subsystem_devtype:
+ * @udev_device: udev device to start searching from
+ * @subsystem: the subsystem of the device
+ * @devtype: the type (DEVTYPE) of the device
+ *
+ * Find the next parent device, with a matching subsystem and devtype
+ * value, and fill in information from the sys device and the udev
+ * database entry.
+ *
+ * If devtype is #NULL, only subsystem is checked, and any devtype will
+ * match.
+ *
+ * The returned the device is not referenced. It is attached to the
+ * child device, and will be cleaned up when the child device
+ * is cleaned up.
+ *
+ * It can be called as many times as needed, without caring about
+ * references.
+ *
+ * Returns: a new udev device, or #NULL if no matching parent exists.
+ **/
struct udev_device *udev_device_get_parent_with_subsystem_devtype(struct udev_device *udev_device, const char *subsystem, const char *devtype)
{
struct udev_device *parent;
free(udev_device->action);
free(udev_device->driver);
free(udev_device->devpath_old);
+ free(udev_device->sysname_old);
free(udev_device->knodename);
udev_list_cleanup_entries(udev_device->udev, &udev_device->sysattr_list);
free(udev_device->envp);
return udev_device->syspath;
}
+/**
+ * udev_device_get_sysname:
+ * @udev_device: udev device
+ *
+ * Returns: the sys name of the device device
+ **/
const char *udev_device_get_sysname(struct udev_device *udev_device)
{
if (udev_device == NULL)
return udev_device->sysname;
}
+/**
+ * udev_device_get_sysnum:
+ * @udev_device: udev device
+ *
+ * Returns: the trailing number of of the device name
+ **/
const char *udev_device_get_sysnum(struct udev_device *udev_device)
{
if (udev_device == NULL)
return NULL;
if (!udev_device->subsystem_set) {
udev_device->subsystem_set = 1;
- /* read "subsytem" link */
+ /* read "subsystem" link */
if (util_get_sys_subsystem(udev_device->udev, udev_device->syspath, subsystem, sizeof(subsystem)) > 0) {
udev_device_set_subsystem(udev_device, subsystem);
return udev_device->subsystem;
return udev_list_get_entry(&udev_device->properties_list);
}
+/**
+ * udev_device_get_driver:
+ * @udev_device: udev device
+ *
+ * Returns: the driver string, or #NULL if there is no driver attached.
+ **/
const char *udev_device_get_driver(struct udev_device *udev_device)
{
char driver[UTIL_NAME_SIZE];
return udev_device->driver;
}
+/**
+ * udev_device_get_devnum:
+ * @udev_device: udev device
+ *
+ * Returns: the device major/minor number.
+ **/
dev_t udev_device_get_devnum(struct udev_device *udev_device)
{
if (udev_device == NULL)
return udev_device->devnum;
}
+/**
+ * udev_device_get_action:
+ * @udev_device: udev device
+ *
+ * This is only valid if the device was received through a monitor. Devices read from
+ * sys do not have an action string. Usual actions are: add, remove, change, online,
+ * offline.
+ *
+ * Returns: the kernel action value, or #NULL if there is no action value available.
+ **/
const char *udev_device_get_action(struct udev_device *udev_device)
{
if (udev_device == NULL)
return udev_device->action;
}
+/**
+ * udev_device_get_devnum:
+ * @udev_device: udev device
+ *
+ * This is only valid if the device was received through a monitor. Devices read from
+ * sys do not have a sequence number.
+ *
+ * Returns: the kernel event sequence number, or 0 if there is no sequence number available.
+ **/
unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device)
{
if (udev_device == NULL)
return udev_device->seqnum;
}
+/**
+ * udev_device_get_sysattr_value:
+ * @udev_device: udev device
+ * @sysattr: attribute name
+ *
+ * The retrieved value is cached in the device. Repeated calls will return the same
+ * value and not open the attribute again.
+ *
+ * Returns: the content of a sys attribute file, or #NULL if there is no sys attribute value.
+ **/
const char *udev_device_get_sysattr_value(struct udev_device *udev_device, const char *sysattr)
{
struct udev_list_entry *list_entry;
return 0;
}
-int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink)
+int udev_device_add_devlink(struct udev_device *udev_device, const char *devlink, int unique)
{
+ struct udev_list_entry *list_entry;
+
udev_device->devlinks_uptodate = 0;
- if (udev_list_entry_add(udev_device->udev, &udev_device->devlinks_list, devlink, NULL, 1, 0) == NULL)
+ list_entry = udev_list_entry_add(udev_device->udev, &udev_device->devlinks_list, devlink, NULL, 1, 0);
+ if (list_entry == NULL)
return -ENOMEM;
+ if (unique)
+ udev_list_entry_set_flag(list_entry, 1);
return 0;
}
struct udev_list_entry *udev_device_add_property_from_string(struct udev_device *udev_device, const char *property)
{
- char name[UTIL_PATH_SIZE];
+ char name[UTIL_LINE_SIZE];
char *val;
util_strscpy(name, sizeof(name), property);
return udev_device_add_property(udev_device, name, val);
}
+/**
+ * udev_device_get_property_value:
+ * @udev_device: udev device
+ * @key: property name
+ *
+ * Returns: the value of a device property, or #NULL if there is no such property.
+ **/
const char *udev_device_get_property_value(struct udev_device *udev_device, const char *key)
{
struct udev_list_entry *list_entry;
s = udev_device->monitor_buf;
l = MONITOR_BUF_SIZE;
udev_list_entry_foreach(list_entry, udev_device_get_properties_list_entry(udev_device)) {
+ const char *key;
+
+ key = udev_list_entry_get_name(list_entry);
+ /* skip private variables */
+ if (key[0] == '.')
+ continue;
+
/* add string to envp array */
udev_device->envp[i++] = s;
if (i+1 >= ENVP_SIZE)
return -EINVAL;
/* add property string to monitor buffer */
- l = util_strpcpyl(&s, l, udev_list_entry_get_name(list_entry), "=",
- udev_list_entry_get_value(list_entry), NULL);
+ l = util_strpcpyl(&s, l, key, "=", udev_list_entry_get_value(list_entry), NULL);
if (l == 0)
return -EINVAL;
+ /* advance past the trailing '\0' that util_strpcpyl() guarantees */
s++;
+ l--;
}
udev_device->envp[i] = NULL;
udev_device->monitor_buf_len = s - udev_device->monitor_buf;
int udev_device_set_devpath_old(struct udev_device *udev_device, const char *devpath_old)
{
+ const char *pos;
+ size_t len;
+
+ free(udev_device->devpath_old);
udev_device->devpath_old = strdup(devpath_old);
if (udev_device->devpath_old == NULL)
return -ENOMEM;
udev_device_add_property(udev_device, "DEVPATH_OLD", udev_device->devpath_old);
+
+ pos = strrchr(udev_device->devpath_old, '/');
+ if (pos == NULL)
+ return -EINVAL;
+ udev_device->sysname_old = strdup(&pos[1]);
+ if (udev_device->sysname_old == NULL)
+ return -ENOMEM;
+
+ /* some devices have '!' in their name, change that to '/' */
+ len = 0;
+ while (udev_device->sysname_old[len] != '\0') {
+ if (udev_device->sysname_old[len] == '!')
+ udev_device->sysname_old[len] = '/';
+ len++;
+ }
return 0;
}
+const char *udev_device_get_sysname_old(struct udev_device *udev_device)
+{
+ if (udev_device == NULL)
+ return NULL;
+ return udev_device->sysname_old;
+}
+
const char *udev_device_get_knodename(struct udev_device *udev_device)
{
return udev_device->knodename;
int udev_device_set_knodename(struct udev_device *udev_device, const char *knodename)
{
+ free(udev_device->knodename);
udev_device->knodename = strdup(knodename);
if (udev_device->knodename == NULL)
return -ENOMEM;
+ udev_device_add_property(udev_device, "DEVNAME", udev_device->knodename);
return 0;
}
~ianmdlvl / elogind.git / blobdiff