X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=libudev%2Flibudev-device.c;h=669c51e35bb7617f24bfb153d0b4061003603dda;hb=8d6bc73aefb5dcfd36d9456ab2209bc410086f82;hp=96cc2dba1c653808dd706055bf8576bfc3ff0031;hpb=a5710160377a85e7c78601e2c45049b392891436;p=elogind.git diff --git a/libudev/libudev-device.c b/libudev/libudev-device.c index 96cc2dba1..669c51e35 100644 --- a/libudev/libudev-device.c +++ b/libudev/libudev-device.c @@ -23,6 +23,21 @@ #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 subsytem. + */ + +/** + * udev_device: + * + * Opaque object representing one kernel sys device. + */ struct udev_device { struct udev *udev; struct udev_device *parent_device; @@ -341,6 +356,23 @@ struct udev_device *udev_device_new_from_syspath(struct udev *udev, const char * 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]; @@ -392,6 +424,22 @@ struct udev_device *udev_device_new_from_devnum(struct udev *udev, char type, de return device; } +/** + * udev_device_new_from_subsystem_sysname: + * @udev: udev library context + * @subsystem: the subsytem 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 subsytem 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]; @@ -495,6 +543,25 @@ static struct udev_device *device_new_from_parent(struct udev_device *udev_devic 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 neccessarily 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) @@ -508,6 +575,25 @@ struct udev_device *udev_device_get_parent(struct udev_device *udev_device) return udev_device->parent_device; } +/** + * udev_device_get_parent_with_subsystem_devtype: + * @udev_device: udev device to start searching from + * @subsystem: the subsytem 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. + * + * 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; @@ -631,6 +717,12 @@ const char *udev_device_get_syspath(struct udev_device *udev_device) 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) @@ -638,6 +730,12 @@ const char *udev_device_get_sysname(struct udev_device *udev_device) 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) @@ -790,6 +888,12 @@ struct udev_list_entry *udev_device_get_properties_list_entry(struct udev_device 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]; @@ -804,6 +908,12 @@ const char *udev_device_get_driver(struct udev_device *udev_device) 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) @@ -813,6 +923,16 @@ dev_t udev_device_get_devnum(struct udev_device *udev_device) 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) @@ -820,6 +940,15 @@ const char *udev_device_get_action(struct udev_device *udev_device) 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) @@ -827,6 +956,16 @@ unsigned long long int udev_device_get_seqnum(struct udev_device *udev_device) 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 reads 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; @@ -1025,6 +1164,13 @@ struct udev_list_entry *udev_device_add_property_from_string(struct udev_device 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;