*
* Generic class utility functions for libsysfs
*
- * Copyright (C) 2003 International Business Machines, Inc.
+ * Copyright (C) IBM Corp. 2003-2005
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
*/
void sysfs_close_class_device(struct sysfs_class_device *dev)
{
- if (dev != NULL) {
- if (dev->directory != NULL)
- sysfs_close_directory(dev->directory);
- if (dev->sysdevice != NULL)
+ if (dev) {
+ if (dev->parent)
+ sysfs_close_class_device(dev->parent);
+ if (dev->sysdevice)
sysfs_close_device(dev->sysdevice);
- if (dev->driver != NULL)
- sysfs_close_driver(dev->driver);
+ if (dev->attrlist)
+ dlist_destroy(dev->attrlist);
free(dev);
}
}
+static void sysfs_close_cls_dev(void *dev)
+{
+ sysfs_close_class_device((struct sysfs_class_device *)dev);
+}
+
/**
- * sysfs_close_class: close single class
- * @class: class structure
- */
+ * sysfs_close_class: close the given class
+ * @cls: sysfs_class to close
+ */
void sysfs_close_class(struct sysfs_class *cls)
{
- struct sysfs_class_device *cur = NULL, *next = NULL;
-
- if (cls != NULL) {
- if (cls->directory != NULL)
- sysfs_close_directory(cls->directory);
- for (cur = cls->devices; cur != NULL; cur = next) {
- next = cur->next;
- sysfs_close_class_device(cur);
- }
+ if (cls) {
+ if (cls->devices)
+ dlist_destroy(cls->devices);
+ if (cls->attrlist)
+ dlist_destroy(cls->attrlist);
free(cls);
}
}
+static int cdev_name_equal(void *a, void *b)
+{
+ if (!a || !b)
+ return 0;
+
+ if (strncmp((char *)a, ((struct sysfs_class_device *)b)->name,
+ strlen((char *)a)) == 0)
+ return 1;
+
+ return 0;
+}
+
+static struct sysfs_class *alloc_class(void)
+{
+ return (struct sysfs_class *) calloc(1, sizeof(struct sysfs_class));
+}
+
/**
* alloc_class_device: mallocs and initializes new class device struct.
* returns sysfs_class_device or NULL.
*/
static struct sysfs_class_device *alloc_class_device(void)
{
- return (struct sysfs_class_device *)
- calloc(1, sizeof(struct sysfs_class_device));
+ struct sysfs_class_device *dev;
+
+ dev = calloc(1, sizeof(struct sysfs_class_device));
+ return dev;
}
/**
- * alloc_class: mallocs new class structure
- * returns sysfs_class struct or NULL
+ * set_classdev_classname: Grabs classname from path
+ * @cdev: class device to set
+ * Returns nothing
*/
-static struct sysfs_class *alloc_class(void)
+static void set_classdev_classname(struct sysfs_class_device *cdev)
{
- return (struct sysfs_class *)calloc(1, sizeof(struct sysfs_class));
+ char *c, *e;
+ int count = 0;
+
+ c = strstr(cdev->path, SYSFS_CLASS_NAME);
+ if (c == NULL) {
+ c = strstr(cdev->path, SYSFS_BLOCK_NAME);
+ } else {
+ c = strstr(c, "/");
+ }
+
+ if (c == NULL)
+ safestrcpy(cdev->classname, SYSFS_UNKNOWN);
+ else {
+ if (*c == '/')
+ c++;
+ e = c;
+ while (e != NULL && *e != '/' && *e != '\0') {
+ e++;
+ count++;
+ }
+ strncpy(cdev->classname, c, count);
+ }
}
/**
- * open_class_dir: opens up sysfs class directory
- * returns sysfs_directory struct with success and NULL with error
+ * sysfs_open_class_device_path: Opens and populates class device
+ * @path: path to class device.
+ * returns struct sysfs_class_device with success and NULL with error.
*/
-static struct sysfs_directory *open_class_dir(const char *name)
+struct sysfs_class_device *sysfs_open_class_device_path(const char *path)
{
- struct sysfs_directory *classdir = NULL;
- char classpath[SYSFS_PATH_MAX];
+ struct sysfs_class_device *cdev;
+ char temp_path[SYSFS_PATH_MAX];
- if (name == NULL) {
+ if (!path) {
errno = EINVAL;
return NULL;
}
- memset(classpath, 0, SYSFS_PATH_MAX);
- if ((sysfs_get_mnt_path(classpath, SYSFS_PATH_MAX)) != 0) {
- dprintf(stderr, "Sysfs not supported on this system\n");
+ /*
+ * Post linux-2.6.14 driver model supports nested classes with
+ * links to the nested hierarchy at /sys/class/xxx/. Check for
+ * a link to the actual class device if a directory isn't found
+ */
+ if (sysfs_path_is_dir(path)) {
+ dprintf("%s: Directory not found, checking for a link\n", path);
+ if (!sysfs_path_is_link(path)) {
+ if (sysfs_get_link(path, temp_path, SYSFS_PATH_MAX)) {
+ dprintf("Error retrieving link at %s\n", path);
+ return NULL;
+ }
+ } else {
+ dprintf("%s is not a valid class device path\n", path);
+ return NULL;
+ }
+ } else
+ safestrcpy(temp_path, path);
+
+ cdev = alloc_class_device();
+ if (!cdev) {
+ dprintf("calloc failed\n");
return NULL;
}
-
- strcat(classpath, SYSFS_CLASS_DIR);
- strcat(classpath, "/");
- strcat(classpath, name);
- classdir = sysfs_open_directory(classpath);
- if (classdir == NULL) {
+ if (sysfs_get_name_from_path(temp_path, cdev->name, SYSFS_NAME_LEN)) {
errno = EINVAL;
- dprintf(stderr,"Class %s not supported on this system\n",
- name);
+ dprintf("Error getting class device name\n");
+ sysfs_close_class_device(cdev);
return NULL;
}
- if ((sysfs_read_directory(classdir)) != 0) {
- dprintf(stderr, "Error reading %s class dir %s\n", name,
- classpath);
- sysfs_close_directory(classdir);
+
+ safestrcpy(cdev->path, temp_path);
+ if (sysfs_remove_trailing_slash(cdev->path)) {
+ dprintf("Invalid path to class device %s\n", cdev->path);
+ sysfs_close_class_device(cdev);
return NULL;
}
+ set_classdev_classname(cdev);
- return classdir;
+ return cdev;
}
-/**
- * sysfs_open_class_device: Opens and populates class device
- * @path: path to class device.
- * returns struct sysfs_class_device with success and NULL with error.
+/**
+ * get_blockdev_parent: Get the parent class device for a "block" subsystem
+ * device if present
+ * @clsdev: block subsystem class device whose parent needs to be found
+ * Returns 0 on success and 1 on error
*/
-struct sysfs_class_device *sysfs_open_class_device(const char *path)
+static int get_blockdev_parent(struct sysfs_class_device *clsdev)
{
- struct sysfs_class_device *cdev = NULL;
- struct sysfs_directory *dir = NULL, *cur = NULL;
- struct sysfs_dlink *curl = NULL;
- struct sysfs_device *sdev = NULL;
- struct sysfs_driver *drv = NULL;
- char temp[SYSFS_NAME_LEN];
+ char parent_path[SYSFS_PATH_MAX];
+ char *c;
+
+ safestrcpy(parent_path, clsdev->path);
+ c = strstr(parent_path, SYSFS_BLOCK_NAME);
+ if (c == NULL) {
+ dprintf("Class device %s does not belong to BLOCK subsystem\n",
+ clsdev->name);
+ return 1;
+ }
+ c += strlen(SYSFS_BLOCK_NAME);
+ if (*c == '/')
+ c++;
+ else
+ goto errout;
+
+ /* validate whether the given class device is a partition or not */
+ if ((strncmp(c, clsdev->name, strlen(clsdev->name))) == 0) {
+ dprintf("%s not a partition\n", clsdev->name);
+ return 1;
+ }
+
+ c = strchr(c, '/');
+ if (c == NULL)
+ goto errout;
+
+ *c = '\0';
+
+ clsdev->parent = sysfs_open_class_device_path(parent_path);
+ if (!clsdev->parent) {
+ dprintf("Error opening the parent class device at %s\n",
+ parent_path);
+ return 1;
+ }
+ return 0;
- if (path == NULL) {
+errout:
+ dprintf("Invalid path %s\n", clsdev->path);
+ return 1;
+}
+
+/**
+ * sysfs_get_classdev_parent: Retrieves the parent of a class device.
+ * eg., when working with hda1, this function can be used to retrieve the
+ * sysfs_class_device for hda
+ *
+ * @clsdev: class device whose parent details are required.
+ * Returns sysfs_class_device of the parent on success, NULL on failure
+ */
+struct sysfs_class_device *sysfs_get_classdev_parent
+ (struct sysfs_class_device *clsdev)
+{
+ if (!clsdev) {
errno = EINVAL;
return NULL;
}
- cdev = alloc_class_device();
- if (cdev == NULL) {
- perror("malloc");
- return NULL;
+ if (clsdev->parent)
+ return (clsdev->parent);
+
+ /*
+ * As of now, only block devices have a parent child heirarchy in sysfs
+ * We do not know, if, in the future, more classes will have a similar
+ * structure. Hence, we now call a specialized function for block and
+ * later we can add support functions for other subsystems as required.
+ */
+ if (!(strncmp(clsdev->classname, SYSFS_BLOCK_NAME,
+ sizeof(SYSFS_BLOCK_NAME)))) {
+ if ((get_blockdev_parent(clsdev)) == 0)
+ return (clsdev->parent);
}
- memset(temp, 0, SYSFS_NAME_LEN);
- if ((sysfs_get_name_from_path(path, temp, SYSFS_NAME_LEN)) != 0) {
+ return NULL;
+}
+
+/**
+ * get_classdev_path: given the class and a device in the class, return the
+ * absolute path to the device
+ * @classname: name of the class
+ * @clsdev: the class device
+ * @path: buffer to return path
+ * @psize: size of "path"
+ * Returns 0 on SUCCESS or -1 on error
+ */
+static int get_classdev_path(const char *classname, const char *clsdev,
+ char *path, size_t len)
+{
+ if (!classname || !clsdev || !path) {
errno = EINVAL;
- dprintf(stderr, "Invalid class device path %s\n", path);
- sysfs_close_class_device(cdev);
- return NULL;
+ return -1;
+ }
+ if (sysfs_get_mnt_path(path, len) != 0) {
+ dprintf("Error getting sysfs mount path\n");
+ return -1;
+ }
+ if (strncmp(classname, SYSFS_BLOCK_NAME,
+ sizeof(SYSFS_BLOCK_NAME)) == 0) {
+ safestrcatmax(path, "/", len);
+ safestrcatmax(path, SYSFS_BLOCK_NAME, len);
+ } else {
+ safestrcatmax(path, "/", len);
+ safestrcatmax(path, SYSFS_CLASS_NAME, len);
+ safestrcatmax(path, "/", len);
+ safestrcatmax(path, classname, len);
}
- strcpy(cdev->name, temp);
+ safestrcatmax(path, "/", len);
+ safestrcatmax(path, clsdev, len);
+ return 0;
+}
- dir = sysfs_open_directory(path);
- if (dir == NULL) {
- dprintf(stderr, "Error opening class device at %s\n", path);
- sysfs_close_class_device(cdev);
+/**
+ * sysfs_open_class_device: Locates a specific class_device and returns it.
+ * Class_device must be closed using sysfs_close_class_device
+ * @classname: Class to search
+ * @name: name of the class_device
+ *
+ * NOTE:
+ * Call sysfs_close_class_device() to close the class device
+ */
+struct sysfs_class_device *sysfs_open_class_device
+ (const char *classname, const char *name)
+{
+ char devpath[SYSFS_PATH_MAX];
+ struct sysfs_class_device *cdev;
+
+ if (!classname || !name) {
+ errno = EINVAL;
return NULL;
}
- if ((sysfs_read_directory(dir)) != 0) {
- dprintf(stderr, "Error reading class device at %s\n", path);
- sysfs_close_directory(dir);
- sysfs_close_class_device(cdev);
+
+ memset(devpath, 0, SYSFS_PATH_MAX);
+ if ((get_classdev_path(classname, name, devpath,
+ SYSFS_PATH_MAX)) != 0) {
+ dprintf("Error getting to device %s on class %s\n",
+ name, classname);
return NULL;
}
- cdev->directory = dir;
-
- cur = cdev->directory->subdirs;
- while(cur != NULL) {
- sysfs_read_directory(cur);
- cur = cur->next;
- }
- /* get driver and device, if implemented */
- curl = cdev->directory->links;
- while (curl != NULL) {
- if (strncmp(curl->name, SYSFS_DEVICES_NAME, 6) == 0) {
- sdev = sysfs_open_device(curl->target->path);
- if (sdev != NULL) {
- cdev->sysdevice = sdev;
- if (cdev->driver != NULL)
- sdev->driver = cdev->driver;
- }
- } else if (strncmp(curl->name, SYSFS_DRIVERS_NAME, 6) == 0) {
- drv = sysfs_open_driver(curl->target->path);
- if (drv != NULL) {
- cdev->driver = drv;
- if (cdev->sysdevice != NULL)
- drv->device = cdev->sysdevice;
- }
- }
- curl = curl->next;
+
+ cdev = sysfs_open_class_device_path(devpath);
+ if (!cdev) {
+ dprintf("Error getting class device %s from class %s\n",
+ name, classname);
+ return NULL;
}
return cdev;
}
/**
- * add_dev_to_class: adds a class device to class list
- * @class: class to add the device
- * @dev: device to add
+ * sysfs_get_classdev_attr: searches class device's attributes by name
+ * @clsdev: class device to look through
+ * @name: attribute name to get
+ * returns sysfs_attribute reference with success or NULL with error
+ */
+struct sysfs_attribute *sysfs_get_classdev_attr
+ (struct sysfs_class_device *clsdev, const char *name)
+{
+ if (!clsdev || !name) {
+ errno = EINVAL;
+ return NULL;
+ }
+ return get_attribute(clsdev, (char *)name);
+}
+
+/**
+ * sysfs_get_classdev_attributes: gets list of classdev attributes
+ * @clsdev: class device whose attributes list is needed
+ * returns dlist of attributes on success or NULL on error
*/
-static void add_dev_to_class(struct sysfs_class *cls,
- struct sysfs_class_device *dev)
+struct dlist *sysfs_get_classdev_attributes(struct sysfs_class_device *clsdev)
{
- if (cls != NULL && dev != NULL) {
- dev->next = cls->devices;
- cls->devices = dev;
+ if (!clsdev) {
+ errno = EINVAL;
+ return NULL;
}
+ return get_attributes_list(clsdev);
}
/**
- * get_all_class_devices: gets all devices for class
- * @class: class to get devices for
- * returns 0 with success and -1 with failure
+ * sysfs_get_classdev_device: gets the sysfs_device associated with the
+ * given sysfs_class_device
+ * @clsdev: class device whose associated sysfs_device is needed
+ * returns struct sysfs_device * on success or NULL on error
*/
-static int get_all_class_devices(struct sysfs_class *cls)
+struct sysfs_device *sysfs_get_classdev_device
+ (struct sysfs_class_device *clsdev)
{
- struct sysfs_class_device *dev = NULL;
- struct sysfs_directory *cur = NULL, *next = NULL;
+ char linkpath[SYSFS_PATH_MAX], devpath[SYSFS_PATH_MAX];
- if (cls == NULL || cls->directory == NULL) {
+ if (!clsdev) {
errno = EINVAL;
- return -1;
+ return NULL;
}
- for (cur = cls->directory->subdirs; cur != NULL; cur = next) {
- next = cur->next;
- dev = sysfs_open_class_device(cur->path);
- if (dev == NULL) {
- dprintf(stderr, "Error opening device at %s\n",
- cur->path);
- continue;
- }
- add_dev_to_class(cls, dev);
+
+ if (clsdev->sysdevice)
+ return clsdev->sysdevice;
+
+ memset(linkpath, 0, SYSFS_PATH_MAX);
+ safestrcpy(linkpath, clsdev->path);
+ safestrcat(linkpath, "/device");
+ if (!sysfs_path_is_link(linkpath)) {
+ memset(devpath, 0, SYSFS_PATH_MAX);
+ if (!sysfs_get_link(linkpath, devpath, SYSFS_PATH_MAX))
+ clsdev->sysdevice = sysfs_open_device_path(devpath);
}
-
- return 0;
+ return clsdev->sysdevice;
}
/**
struct sysfs_class *sysfs_open_class(const char *name)
{
struct sysfs_class *cls = NULL;
- struct sysfs_directory *classdir = NULL;
+ char classpath[SYSFS_PATH_MAX];
- if (name == NULL) {
+ if (!name) {
errno = EINVAL;
return NULL;
}
+ memset(classpath, 0, SYSFS_PATH_MAX);
+ if ((sysfs_get_mnt_path(classpath, SYSFS_PATH_MAX)) != 0) {
+ dprintf("Sysfs not supported on this system\n");
+ return NULL;
+ }
+
+ /*
+ * We shall now treat "block" also as a class. Hence, check here
+ * if "name" is "block" and proceed accordingly
+ */
+ if (strcmp(name, SYSFS_BLOCK_NAME) == 0) {
+ safestrcat(classpath, "/");
+ safestrcat(classpath, SYSFS_BLOCK_NAME);
+ } else {
+ safestrcat(classpath, "/");
+ safestrcat(classpath, SYSFS_CLASS_NAME);
+ safestrcat(classpath, "/");
+ safestrcat(classpath, name);
+ }
+ if (sysfs_path_is_dir(classpath)) {
+ dprintf("Class %s not found on the system\n", name);
+ return NULL;
+ }
+
cls = alloc_class();
if (cls == NULL) {
- perror("malloc");
+ dprintf("calloc failed\n");
return NULL;
}
- strcpy(cls->name, name);
- classdir = open_class_dir(name);
- if (classdir == NULL) {
- dprintf(stderr,
- "Invalid class, %s not supported on this system\n",
- name);
+ safestrcpy(cls->name, name);
+ safestrcpy(cls->path, classpath);
+ if ((sysfs_remove_trailing_slash(cls->path)) != 0) {
+ dprintf("Invalid path to class device %s\n", cls->path);
sysfs_close_class(cls);
return NULL;
}
- cls->directory = classdir;
- if ((get_all_class_devices(cls)) != 0) {
- dprintf(stderr, "Error reading %s class devices\n", name);
- sysfs_close_class(cls);
+
+ return cls;
+}
+
+/**
+ * sysfs_get_class_device: get specific class device using the device's id
+ * @cls: sysfs_class to find the device on
+ * @name: name of the class device to look for
+ *
+ * Returns sysfs_class_device * on success and NULL on failure
+ */
+struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *cls,
+ const char *name)
+{
+ char path[SYSFS_PATH_MAX];
+ struct sysfs_class_device *cdev = NULL;
+
+ if (!cls || !name) {
+ errno = EINVAL;
return NULL;
}
- return cls;
+ if (cls->devices) {
+ cdev = (struct sysfs_class_device *)dlist_find_custom
+ (cls->devices, (void *)name, cdev_name_equal);
+ if (cdev)
+ return cdev;
+ }
+
+ safestrcpy(path, cls->path);
+ safestrcat(path, "/");
+ safestrcat(path, name);
+ cdev = sysfs_open_class_device_path(path);
+ if (!cdev) {
+ dprintf("Error opening class device at %s\n", path);
+ return NULL;
+ }
+ if (!cls->devices)
+ cls->devices = dlist_new_with_delete
+ (sizeof(struct sysfs_class_device),
+ sysfs_close_cls_dev);
+
+ dlist_unshift_sorted(cls->devices, cdev, sort_list);
+ return cdev;
+}
+
+/**
+ * Add class devices to list
+ */
+static void add_cdevs_to_classlist(struct sysfs_class *cls, struct dlist *list)
+{
+ char path[SYSFS_PATH_MAX], *cdev_name;
+ struct sysfs_class_device *cdev = NULL;
+
+ if (cls == NULL || list == NULL)
+ return;
+
+ dlist_for_each_data(list, cdev_name, char) {
+ if (cls->devices) {
+ cdev = (struct sysfs_class_device *)
+ dlist_find_custom(cls->devices,
+ (void *)cdev_name, cdev_name_equal);
+ if (cdev)
+ continue;
+ }
+ safestrcpy(path, cls->path);
+ safestrcat(path, "/");
+ safestrcat(path, cdev_name);
+ cdev = sysfs_open_class_device_path(path);
+ if (cdev) {
+ if (!cls->devices)
+ cls->devices = dlist_new_with_delete
+ (sizeof(struct sysfs_class_device),
+ sysfs_close_cls_dev);
+ dlist_unshift_sorted(cls->devices, cdev,
+ sort_list);
+ }
+ }
+}
+
+/**
+ * sysfs_get_class_devices: get all class devices in the given class
+ * @cls: sysfs_class whose devices list is needed
+ *
+ * Returns a dlist of sysfs_class_device * on success and NULL on failure
+ */
+struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
+{
+ char path[SYSFS_PATH_MAX];
+ struct dlist *dirlist, *linklist;
+
+ if (!cls) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ /*
+ * Post linux-2.6.14, we have nested classes and links under
+ * /sys/class/xxx/. are also valid class devices
+ */
+ safestrcpy(path, cls->path);
+ dirlist = read_dir_subdirs(path);
+ if (dirlist) {
+ add_cdevs_to_classlist(cls, dirlist);
+ sysfs_close_list(dirlist);
+ }
+
+ linklist = read_dir_links(path);
+ if (linklist) {
+ add_cdevs_to_classlist(cls, linklist);
+ sysfs_close_list(linklist);
+ }
+
+ return cls->devices;
}
~ianmdlvl / elogind.git / blobdiff