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libsysfs: translate devpath of the symlinked class devices to its real path

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This commit is contained in:
Ananth N Mavinakayanahalli 2005-11-02 04:02:33 +01:00 committed by Kay Sievers
parent 0c25d156b0
commit 7a551dc355
1 changed files with 73 additions and 37 deletions
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110
libsysfs/sysfs_class.c
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@ -128,28 +128,45 @@ static void set_classdev_classname(struct sysfs_class_device *cdev)
struct sysfs_class_device *sysfs_open_class_device_path(const char *path)
{
struct sysfs_class_device *cdev;
char temp_path[SYSFS_PATH_MAX];
if (!path) {
errno = EINVAL;
return NULL;
}
/*
* 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 is not a valid path to a class device\n", path);
return NULL;
}
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;
}
if (sysfs_get_name_from_path(path, cdev->name, SYSFS_NAME_LEN)) {
if (sysfs_get_name_from_path(temp_path, cdev->name, SYSFS_NAME_LEN)) {
errno = EINVAL;
dprintf("Error getting class device name\n");
sysfs_close_class_device(cdev);
return NULL;
}
safestrcpy(cdev->path, path);
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);
@ -455,12 +472,10 @@ struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *cls,
safestrcpy(path, cls->path);
safestrcat(path, "/");
safestrcat(path, name);
if (!sysfs_path_is_dir(path)) {
cdev = sysfs_open_class_device_path(path);
if (!cdev) {
dprintf("Error opening class device at %s\n", path);
return NULL;
}
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
@ -471,6 +486,40 @@ struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *cls,
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
@ -480,42 +529,29 @@ struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *cls,
struct dlist *sysfs_get_class_devices(struct sysfs_class *cls)
{
char path[SYSFS_PATH_MAX];
char *cdev_name;
struct sysfs_class_device *cdev = NULL;
struct dlist *dirlist;
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) {
dlist_for_each_data(dirlist, 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);
}
}
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;
}