#include "libsysfs.h"
#include "sysfs.h"
-void sysfs_close_cls_dev(void *dev)
+static void sysfs_close_cls_dev(void *dev)
{
sysfs_close_class_device((struct sysfs_class_device *)dev);
}
sysfs_close_device(dev->sysdevice);
if (dev->driver != NULL)
sysfs_close_driver(dev->driver);
+ if (dev->parent != NULL)
+ sysfs_close_class_device(dev->parent);
free(dev);
}
}
return (struct sysfs_class *)calloc(1, sizeof(struct sysfs_class));
}
-/**
- * open_class_dir: opens up sysfs class directory
- * returns sysfs_directory struct with success and NULL with error
+/**
+ * set_classdev_classname: Grabs classname from path
+ * @cdev: class device to set
+ * Returns nothing
*/
-static struct sysfs_directory *open_class_dir(const unsigned char *name)
+static void set_classdev_classname(struct sysfs_class_device *cdev)
{
- struct sysfs_directory *classdir = NULL;
- unsigned char classpath[SYSFS_PATH_MAX];
-
- if (name == NULL) {
- 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;
- }
-
- strcat(classpath, SYSFS_CLASS_DIR);
- strcat(classpath, "/");
- strcat(classpath, name);
- classdir = sysfs_open_directory(classpath);
- if (classdir == NULL) {
- errno = EINVAL;
- dprintf("Class %s not supported on this system\n", name);
- return NULL;
- }
- if ((sysfs_read_directory(classdir)) != 0) {
- dprintf("Error reading %s class dir %s\n", name, classpath);
- sysfs_close_directory(classdir);
- return NULL;
+ unsigned char *c = NULL, *e = NULL;
+ 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)
+ strcpy(cdev->classname, SYSFS_UNKNOWN);
+ else {
+ if (*c == '/')
+ c++;
+ e = c;
+ while (e != NULL && *e != '/' && *e != '\0') {
+ e++;
+ count++;
+ }
+ strncpy(cdev->classname, c, count);
}
-
- return classdir;
}
/**
- * sysfs_open_class_device: Opens and populates class device
+ * 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.
*/
-struct sysfs_class_device *sysfs_open_class_device(const unsigned char *path)
+struct sysfs_class_device *sysfs_open_class_device_path
+ (const unsigned char *path)
{
struct sysfs_class_device *cdev = NULL;
- struct sysfs_directory *dir = NULL;
- struct sysfs_link *curl = NULL;
- struct sysfs_device *sdev = NULL;
- struct sysfs_driver *drv = NULL;
if (path == NULL) {
errno = EINVAL;
return NULL;
}
+ if ((sysfs_path_is_dir(path)) != 0) {
+ dprintf("%s is not a valid path to a class device\n", path);
+ return NULL;
+ }
cdev = alloc_class_device();
if (cdev == NULL) {
dprintf("calloc failed\n");
}
if ((sysfs_get_name_from_path(path, cdev->name, SYSFS_NAME_LEN)) != 0) {
errno = EINVAL;
- dprintf("Invalid class device path %s\n", path);
+ dprintf("Error getting class device name\n");
sysfs_close_class_device(cdev);
return NULL;
}
- dir = sysfs_open_directory(path);
- if (dir == NULL) {
- dprintf("Error opening class device at %s\n", path);
- sysfs_close_class_device(cdev);
- return NULL;
- }
- if ((sysfs_read_directory(dir)) != 0) {
- dprintf("Error reading class device at %s\n", path);
- sysfs_close_directory(dir);
+ strcpy(cdev->path, path);
+ if ((sysfs_remove_trailing_slash(cdev->path)) != 0) {
+ dprintf("Invalid path to class device %s\n", cdev->path);
sysfs_close_class_device(cdev);
return NULL;
}
- sysfs_read_all_subdirs(dir);
- cdev->directory = dir;
- strcpy(cdev->path, dir->path);
-
- /* get driver and device, if implemented */
- if (cdev->directory->links != NULL) {
- dlist_for_each_data(cdev->directory->links, curl,
- struct sysfs_link) {
- if (strncmp(curl->name, SYSFS_DEVICES_NAME, 6) == 0) {
- sdev = sysfs_open_device(curl->target);
- if (sdev != NULL) {
- cdev->sysdevice = sdev;
- if (cdev->driver != NULL)
- strncpy(sdev->driver_name,
- cdev->driver->name,
- SYSFS_NAME_LEN);
- }
- } else if (strncmp(curl->name,
- SYSFS_DRIVERS_NAME, 6) == 0) {
- drv = sysfs_open_driver(curl->target);
- if (drv != NULL) {
- cdev->driver = drv;
- if (cdev->sysdevice != NULL) {
- strncpy(cdev->sysdevice->name,
- drv->name,
- SYSFS_NAME_LEN);
- if (drv->devices == NULL)
- drv->devices =
- dlist_new
- (sizeof(struct
- sysfs_device));
- dlist_unshift(drv->devices,
- cdev->sysdevice);
- }
- }
- }
- }
- }
+ set_classdev_classname(cdev);
+
return cdev;
}
/**
- * get_all_class_devices: gets all devices for class
+ * sysfs_get_class_devices: gets all devices for class
* @class: class to get devices for
- * returns 0 with success and -1 with failure
+ * returns dlist of class_devices with success and NULL with error
*/
-static int get_all_class_devices(struct sysfs_class *cls)
+struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
{
struct sysfs_class_device *dev = NULL;
struct sysfs_directory *cur = NULL;
- if (cls == NULL || cls->directory == NULL) {
+ if (cls == NULL) {
errno = EINVAL;
- return -1;
+ return NULL;
}
- if (cls->directory->subdirs == NULL)
- return 0;
- dlist_for_each_data(cls->directory->subdirs, cur,
- struct sysfs_directory) {
- dev = sysfs_open_class_device(cur->path);
- if (dev == NULL) {
- dprintf("Error opening device at %s\n", cur->path);
- continue;
- }
- if (cls->devices == NULL)
- cls->devices = dlist_new_with_delete
+
+ if (cls->devices != NULL)
+ return cls->devices;
+
+ if (cls->directory == NULL) {
+ cls->directory = sysfs_open_directory(cls->path);
+ if (cls->directory == NULL)
+ return NULL;
+ }
+
+ if ((sysfs_read_dir_subdirs(cls->directory)) != 0)
+ return NULL;
+
+ if (cls->directory->subdirs != NULL) {
+ dlist_for_each_data(cls->directory->subdirs, cur,
+ struct sysfs_directory) {
+ dev = sysfs_open_class_device_path(cur->path);
+ if (dev == NULL) {
+ dprintf("Error opening device at %s\n",
+ cur->path);
+ continue;
+ }
+ if (cls->devices == NULL)
+ cls->devices = dlist_new_with_delete
(sizeof(struct sysfs_class_device),
sysfs_close_cls_dev);
- dlist_unshift(cls->devices, dev);
+ dlist_unshift(cls->devices, dev);
+ }
}
- return 0;
+ return cls->devices;
}
/**
struct sysfs_class *sysfs_open_class(const unsigned char *name)
{
struct sysfs_class *cls = NULL;
- struct sysfs_directory *classdir = NULL;
+ unsigned char classpath[SYSFS_PATH_MAX];
if (name == NULL) {
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) {
+ strcat(classpath, "/");
+ strcat(classpath, SYSFS_BLOCK_NAME);
+ } else {
+ strcat(classpath, "/");
+ strcat(classpath, SYSFS_CLASS_NAME);
+ strcat(classpath, "/");
+ strcat(classpath, name);
+ }
+ if ((sysfs_path_is_dir(classpath)) != 0) {
+ dprintf("Class %s not found on the system\n", name);
+ return NULL;
+ }
+
cls = alloc_class();
if (cls == NULL) {
dprintf("calloc failed\n");
return NULL;
}
strcpy(cls->name, name);
- classdir = open_class_dir(name);
- if (classdir == NULL) {
- dprintf("Invalid class, %s not supported on this system\n",
- name);
+ strcpy(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;
- strcpy(cls->path, classdir->path);
- if ((get_all_class_devices(cls)) != 0) {
- dprintf("Error reading %s class devices\n", name);
- sysfs_close_class(cls);
- return NULL;
- }
-
+
return cls;
}
return NULL;
}
+ if (class->devices == NULL) {
+ class->devices = sysfs_get_class_devices(class);
+ if (class->devices == NULL)
+ return NULL;
+ }
return (struct sysfs_class_device *)dlist_find_custom(class->devices,
name, class_name_equal);
}
/**
- * sysfs_open_class_device_by_name: Locates a specific class_device and returns it.
+ * sysfs_get_classdev_device: returns the sysfs_device corresponding to
+ * sysfs_class_device, if present
+ * @clsdev: class device whose sysfs_device is required
+ * Returns sysfs_device on success, NULL on error or if device is not
+ * implemented
+ */
+struct sysfs_device *sysfs_get_classdev_device
+ (struct sysfs_class_device *clsdev)
+{
+ struct sysfs_link *devlink = NULL;
+ unsigned char devpath[SYSFS_PATH_MAX];
+
+ if (clsdev == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+ strcpy(devpath, clsdev->path);
+ strcat(devpath, "/device");
+ if ((sysfs_path_is_link(devpath)) != 0) {
+ if (clsdev->sysdevice != NULL) {
+ sysfs_close_device(clsdev->sysdevice);
+ clsdev->sysdevice = NULL;
+ }
+ return NULL;
+ }
+
+ if (clsdev->directory == NULL) {
+ clsdev->directory = sysfs_open_directory(clsdev->path);
+ if (clsdev->directory == NULL)
+ return NULL;
+ }
+ devlink = sysfs_get_directory_link(clsdev->directory, "device");
+ if (devlink == NULL) {
+ if (clsdev->sysdevice != NULL) {
+ dprintf("Device link no longer exists\n");
+ sysfs_close_device(clsdev->sysdevice);
+ clsdev->sysdevice = NULL;
+ }
+ return NULL;
+ }
+
+ if (clsdev->sysdevice != NULL) {
+ if (!strncmp(devlink->target, clsdev->sysdevice->path,
+ SYSFS_PATH_MAX))
+ /* sysdevice hasn't changed */
+ return (clsdev->sysdevice);
+ else
+ /* come here only if the device link for has changed */
+ sysfs_close_device(clsdev->sysdevice);
+ }
+
+ clsdev->sysdevice = sysfs_open_device_path(devlink->target);
+ if (clsdev->sysdevice == NULL)
+ return NULL;
+ if (clsdev->driver != NULL)
+ strcpy(clsdev->sysdevice->driver_name, clsdev->driver->name);
+
+ return (clsdev->sysdevice);
+}
+
+/**
+ * sysfs_get_classdev_driver: returns the sysfs_driver corresponding to
+ * sysfs_class_device, if present
+ * @clsdev: class device whose sysfs_device is required
+ * Returns sysfs_driver on success, NULL on error or if driver is not
+ * implemented
+ */
+struct sysfs_driver *sysfs_get_classdev_driver
+ (struct sysfs_class_device *clsdev)
+{
+ struct sysfs_link *drvlink = NULL;
+ unsigned char drvpath[SYSFS_PATH_MAX];
+
+ if (clsdev == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+ strcpy(drvpath, clsdev->path);
+ strcat(drvpath, "/driver");
+ if ((sysfs_path_is_link(drvpath)) != 0) {
+ if (clsdev->driver != NULL) {
+ sysfs_close_driver(clsdev->driver);
+ clsdev->driver = NULL;
+ }
+ return NULL;
+ }
+
+ if (clsdev->directory == NULL) {
+ clsdev->directory = sysfs_open_directory(clsdev->path);
+ if (clsdev->directory == NULL)
+ return NULL;
+ }
+ drvlink = sysfs_get_directory_link(clsdev->directory, "driver");
+ if (drvlink == NULL) {
+ if (clsdev->driver != NULL) {
+ dprintf("Driver link no longer exists\n");
+ sysfs_close_driver(clsdev->driver);
+ clsdev->driver = NULL;
+ }
+ return NULL;
+ }
+ if (clsdev->driver != NULL) {
+ if (!strncmp(drvlink->target, clsdev->driver->path,
+ SYSFS_PATH_MAX))
+ /* driver hasn't changed */
+ return (clsdev->driver);
+ else
+ /* come here only if the device link for has changed */
+ sysfs_close_driver(clsdev->driver);
+ }
+
+ clsdev->driver = sysfs_open_driver_path(drvlink->target);
+ if (clsdev->driver == NULL)
+ return NULL;
+ if (clsdev->sysdevice != NULL)
+ strcpy(clsdev->sysdevice->driver_name, clsdev->driver->name);
+
+ return (clsdev->driver);
+}
+
+/**
+ * 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
+ */
+static int get_blockdev_parent(struct sysfs_class_device *clsdev)
+{
+ unsigned char parent_path[SYSFS_PATH_MAX], *c = NULL;
+
+ strcpy(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 == NULL) {
+ dprintf("Error opening the parent class device at %s\n",
+ parent_path);
+ return 1;
+ }
+ return 0;
+
+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 == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+ if (clsdev->parent != NULL)
+ 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 (!(strcmp(clsdev->classname, SYSFS_BLOCK_NAME))) {
+ if ((get_blockdev_parent(clsdev)) == 0)
+ return (clsdev->parent);
+ }
+ 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 unsigned char *classname,
+ const unsigned char *clsdev, unsigned char *path, size_t len)
+{
+ if (classname == NULL || clsdev == NULL || path == NULL) {
+ errno = EINVAL;
+ return -1;
+ }
+ if (sysfs_get_mnt_path(path, len) != 0) {
+ dprintf("Error getting sysfs mount path\n");
+ return -1;
+ }
+ if (strcmp(classname, SYSFS_BLOCK_NAME) == 0) {
+ strcat(path, "/");
+ strcat(path, SYSFS_BLOCK_NAME);
+ } else {
+ strcat(path, "/");
+ strcat(path, SYSFS_CLASS_NAME);
+ strcat(path, "/");
+ strcat(path, classname);
+ }
+ strcat(path, "/");
+ strcat(path, clsdev);
+ return 0;
+}
+
+/**
+ * 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_by_name
- (const unsigned char *classname, unsigned char *name)
+struct sysfs_class_device *sysfs_open_class_device
+ (const unsigned char *classname, const unsigned char *name)
{
- struct sysfs_class *class = NULL;
- struct sysfs_class_device *cdev = NULL, *rcdev = NULL;
+ unsigned char devpath[SYSFS_PATH_MAX];
+ struct sysfs_class_device *cdev = NULL;
if (classname == NULL || name == NULL) {
errno = EINVAL;
return NULL;
}
- class = sysfs_open_class(classname);
- if (class == NULL) {
- dprintf("Error opening class %s\n", classname);
+ 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 = sysfs_get_class_device(class, name);
+
+ cdev = sysfs_open_class_device_path(devpath);
if (cdev == NULL) {
dprintf("Error getting class device %s from class %s\n",
name, classname);
- sysfs_close_class(class);
return NULL;
}
-
- rcdev = sysfs_open_class_device(cdev->directory->path);
- if (rcdev == NULL) {
- dprintf("Error getting class device %s from class %s\n",
- name, classname);
- sysfs_close_class(class);
- return NULL;
- }
- sysfs_close_class(class);
-
- return rcdev;
+ return cdev;
}
/**
*/
struct dlist *sysfs_get_classdev_attributes(struct sysfs_class_device *cdev)
{
- if (cdev == NULL || cdev->directory == NULL)
+ if (cdev == NULL)
return NULL;
+ if (cdev->directory == NULL) {
+ cdev->directory = sysfs_open_directory(cdev->path);
+ if (cdev->directory == NULL)
+ return NULL;
+ }
+ if (cdev->directory->attributes == NULL) {
+ if ((sysfs_read_dir_attributes(cdev->directory)) != 0)
+ return NULL;
+ }
return (cdev->directory->attributes);
}
/**
- * sysfs_find_device_class: locates the device the device is on
- * @bus_id: device to look for
- * @classname: buffer to copy class name to
- * @bsize: size of buffer
- * returns 0 with success and -1 with error
+ * sysfs_refresh_clsassdev_attributes: refreshes the driver's list of attributes
+ * @clsdev: sysfs_class_device whose attributes to refresh
+ *
+ * NOTE: Upon return, prior references to sysfs_attributes for this classdev
+ * _may_ not be valid
+ *
+ * Returns list of attributes on success and NULL on failure
*/
-int sysfs_find_device_class(const unsigned char *bus_id,
- unsigned char *classname, size_t bsize)
+struct dlist *sysfs_refresh_classdev_attributes
+ (struct sysfs_class_device *clsdev)
{
- unsigned char class[SYSFS_NAME_LEN], clspath[SYSFS_NAME_LEN];
- unsigned char *cls = NULL, *clsdev = NULL;
- struct dlist *clslist = NULL, *clsdev_list = NULL;
-
- if (bus_id == NULL || classname == NULL) {
+ if (clsdev == NULL) {
errno = EINVAL;
- return -1;
+ return NULL;
}
- strcpy(class, SYSFS_CLASS_DIR);
- clslist = sysfs_open_subsystem_list(class);
- if (clslist != NULL) {
- dlist_for_each_data(clslist, cls, char) {
- memset(clspath, 0, SYSFS_NAME_LEN);
- strcpy(clspath, SYSFS_CLASS_DIR);
- strcat(clspath, "/");
- strcat(clspath, cls);
- clsdev_list = sysfs_open_subsystem_list(clspath);
- if (clsdev_list != NULL) {
- dlist_for_each_data(clsdev_list,
- clsdev, char) {
- if (strcmp(bus_id, clsdev) == 0) {
- strncpy(classname,
- cls, bsize);
- sysfs_close_list(clsdev_list);
- sysfs_close_list(clslist);
- return 0;
- }
- }
- sysfs_close_list(clsdev_list);
- }
- }
- sysfs_close_list(clslist);
+ if (clsdev->directory == NULL)
+ return (sysfs_get_classdev_attributes(clsdev));
+
+ if ((sysfs_refresh_dir_attributes(clsdev->directory)) != 0) {
+ dprintf("Error refreshing class_device attributes\n");
+ return NULL;
}
- return -1;
+
+ return (clsdev->directory->attributes);
}
/**
(struct sysfs_class_device *clsdev, const unsigned char *name)
{
struct sysfs_attribute *cur = NULL;
-
- if (clsdev == NULL || clsdev->directory == NULL ||
- clsdev->directory->attributes == NULL || name == NULL) {
+ struct sysfs_directory *sdir = NULL;
+ struct dlist *attrlist = NULL;
+
+ if (clsdev == NULL || name == NULL) {
errno = EINVAL;
return NULL;
}
-
- cur = sysfs_get_directory_attribute(clsdev->directory,
- (unsigned char *)name);
- if (cur != NULL)
- return cur;
-
- return NULL;
-}
-
-/**
- * sysfs_write_classdev_attr: modify writable attribute value for the given
- * class device
- * @dev: class device name for which the attribute has to be changed
- * @attrib: attribute to change
- * @value: value to change to
- * @len: size of buffer at "value"
- * Returns 0 on success and -1 on error
- */
-int sysfs_write_classdev_attr(unsigned char *dev, unsigned char *attrib,
- unsigned char *value, size_t len)
-{
- struct sysfs_class_device *clsdev = NULL;
- struct sysfs_attribute *attribute = NULL;
- unsigned char class_name[SYSFS_NAME_LEN];
-
- if (dev == NULL || attrib == NULL || value == NULL) {
- errno = EINVAL;
- return -1;
- }
- memset(class_name, 0, SYSFS_NAME_LEN);
- if ((sysfs_find_device_class(dev,
- class_name, SYSFS_NAME_LEN)) < 0) {
- dprintf("Class device %s not found\n", dev);
- return -1;
- }
- clsdev = sysfs_open_class_device_by_name(class_name, dev);
- if (clsdev == NULL) {
- dprintf("Error opening %s in class %s\n", dev, class_name);
- return -1;
- }
- attribute = sysfs_get_directory_attribute(clsdev->directory, attrib);
- if (attribute == NULL) {
- dprintf("Attribute %s not defined for device %s on class %s\n",
- attrib, dev, class_name);
- sysfs_close_class_device(clsdev);
- return -1;
- }
- if ((sysfs_write_attribute(attribute, value, len)) < 0) {
- dprintf("Error setting %s to %s\n", attrib, value);
- sysfs_close_class_device(clsdev);
- return -1;
+ /*
+ * First, see if it's in the current directory. Then look at
+ * subdirs since class devices can have subdirs of attributes.
+ */
+ attrlist = sysfs_get_classdev_attributes(clsdev);
+ if (attrlist != NULL) {
+ cur = sysfs_get_directory_attribute(clsdev->directory,
+ (unsigned char *)name);
+ if (cur != NULL)
+ return cur;
+ }
+
+ if (clsdev->directory->subdirs == NULL)
+ if ((sysfs_read_dir_subdirs(clsdev->directory)) != 0 ||
+ clsdev->directory->subdirs == NULL)
+ return NULL;
+
+ if (clsdev->directory->subdirs != NULL) {
+ dlist_for_each_data(clsdev->directory->subdirs, sdir,
+ struct sysfs_directory) {
+ if ((sysfs_path_is_dir(sdir->path)) != 0)
+ continue;
+ cur = sysfs_get_directory_attribute(sdir,
+ (unsigned char *)name);
+ if (cur == NULL)
+ continue;
+ }
}
- sysfs_close_class_device(clsdev);
- return 0;
+ return cur;
}
/**
- * sysfs_read_classdev_attr: read an attribute for a given class device
+ * sysfs_open_classdev_attr: read an attribute for a given class device
+ * @classname: name of the class on which to look
* @dev: class device name for which the attribute has to be read
* @attrib: attribute to read
- * @value: buffer to return value to user
- * @len: size of buffer at "value"
- * Returns 0 on success and -1 on error
+ * Returns sysfs_attribute * on SUCCESS and NULL on error
+ *
+ * NOTE:
+ * A call to sysfs_close_attribute() is required to close the
+ * attribute returned and to free memory
*/
-int sysfs_read_classdev_attr(unsigned char *dev, unsigned char *attrib,
- unsigned char *value, size_t len)
+struct sysfs_attribute *sysfs_open_classdev_attr(const unsigned char *classname,
+ const unsigned char *dev, const unsigned char *attrib)
{
- struct sysfs_class_device *clsdev = NULL;
struct sysfs_attribute *attribute = NULL;
- unsigned char class_name[SYSFS_NAME_LEN];
+ unsigned char path[SYSFS_PATH_MAX];
- if (dev == NULL || attrib == NULL || value == NULL) {
+ if (classname == NULL || dev == NULL || attrib == NULL) {
errno = EINVAL;
- return -1;
- }
-
- memset(class_name, 0, SYSFS_NAME_LEN);
- if ((sysfs_find_device_class(dev,
- class_name, SYSFS_NAME_LEN)) < 0) {
- dprintf("Class device %s not found\n", dev);
- return -1;
+ return NULL;
}
- clsdev = sysfs_open_class_device_by_name(class_name, dev);
- if (clsdev == NULL) {
- dprintf("Error opening %s in class %s\n", dev, class_name);
- return -1;
+ memset(path, 0, SYSFS_PATH_MAX);
+ if ((get_classdev_path(classname, dev, path, SYSFS_PATH_MAX)) != 0) {
+ dprintf("Error getting to device %s on class %s\n",
+ dev, classname);
+ return NULL;
}
- attribute = sysfs_get_directory_attribute(clsdev->directory, attrib);
+ strcat(path, "/");
+ strcat(path, attrib);
+ attribute = sysfs_open_attribute(path);
if (attribute == NULL) {
- dprintf("Attribute %s not defined for device %s on class %s\n",
- attrib, dev, class_name);
- sysfs_close_class_device(clsdev);
- return -1;
+ dprintf("Error opening attribute %s on class device %s\n",
+ attrib, dev);
+ return NULL;
}
- if (attribute->len > len) {
- dprintf("Value length %d is greater that suppled buffer %d\n",
- attribute->len, len);
- sysfs_close_class_device(clsdev);
- return -1;
+ if ((sysfs_read_attribute(attribute)) != 0) {
+ dprintf("Error reading attribute %s for class device %s\n",
+ attrib, dev);
+ sysfs_close_attribute(attribute);
+ return NULL;
}
- strncpy(value, attribute->value, attribute->len);
- value[(attribute->len)+1] = 0;
- sysfs_close_class_device(clsdev);
- return 0;
+ return attribute;
}
+
~ianmdlvl / elogind.git / blobdiff