summaryrefslogtreecommitdiff
path: root/lib/sysfs_driver.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/sysfs_driver.c')
-rw-r--r--lib/sysfs_driver.c379
1 files changed, 356 insertions, 23 deletions
diff --git a/lib/sysfs_driver.c b/lib/sysfs_driver.c
index 6813c85..88d26b5 100644
--- a/lib/sysfs_driver.c
+++ b/lib/sysfs_driver.c
@@ -3,7 +3,7 @@
*
* Driver utility functions for libsysfs
*
- * Copyright (C) 2003 International Business Machines, Inc.
+ * Copyright (C) IBM Corp. 2003
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
@@ -23,18 +23,47 @@
#include "libsysfs.h"
#include "sysfs.h"
-/**
- * sysfs_close_driver: closes and cleans up driver structure
+static void sysfs_close_driver_device(void *device)
+{
+ sysfs_close_device((struct sysfs_device *)device);
+}
+
+/**
+ * sysfs_close_driver: closes driver and deletes device lists too
* @driver: driver to close
- */
+ */
void sysfs_close_driver(struct sysfs_driver *driver)
{
if (driver != NULL) {
+ if (driver->devices != NULL)
+ dlist_destroy(driver->devices);
if (driver->directory != NULL)
sysfs_close_directory(driver->directory);
free(driver);
}
}
+
+/**
+ * open_driver_dir: Open the sysfs_directory for this driver
+ * @driver: Driver whose directory to be opened
+ * Returns 0 on success and 1 on failure
+ */
+static int open_driver_dir(struct sysfs_driver *driver)
+{
+ if (driver == NULL) {
+ errno = EINVAL;
+ return 1;
+ }
+ if (driver->directory == NULL) {
+ driver->directory = sysfs_open_directory(driver->path);
+ if (driver->directory == NULL) {
+ dprintf("Error opening driver directory at %s\n",
+ driver->path);
+ return 1;
+ }
+ }
+ return 0;
+}
/**
* alloc_driver: allocates and initializes driver
@@ -46,44 +75,348 @@ static struct sysfs_driver *alloc_driver(void)
}
/**
- * sysfs_open_driver: opens and initializes driver structure
+ * sysfs_open_driver_path: opens and initializes driver structure
* @path: path to driver directory
* returns struct sysfs_driver with success and NULL with error
*/
-struct sysfs_driver *sysfs_open_driver(const char *path)
+struct sysfs_driver *sysfs_open_driver_path(const char *path)
{
struct sysfs_driver *driver = NULL;
- struct sysfs_directory *sdir = NULL;
- char devname[SYSFS_NAME_LEN];
if (path == NULL) {
errno = EINVAL;
return NULL;
}
- sdir = sysfs_open_directory(path);
- if (sdir == NULL) {
- dprintf (stderr, "Error opening directory %s\n", path);
- return NULL;
- }
- if ((sysfs_read_directory(sdir)) != 0) {
- dprintf (stderr, "Error reading directory %s\n", path);
- sysfs_close_directory(sdir);
+ if ((sysfs_path_is_dir(path)) != 0) {
+ dprintf("Invalid path to driver: %s\n", path);
return NULL;
}
driver = alloc_driver();
if (driver == NULL) {
- dprintf(stderr, "Error allocating driver at %s\n", path);
- sysfs_close_directory(sdir);
+ dprintf("Error allocating driver at %s\n", path);
return NULL;
}
- if ((sysfs_get_name_from_path(path, devname, SYSFS_NAME_LEN)) != 0) {
- dprintf (stderr, "Error reading directory %s\n", path);
- sysfs_close_directory(sdir);
+ if ((sysfs_get_name_from_path(path, driver->name,
+ SYSFS_NAME_LEN)) != 0) {
+ dprintf("Error getting driver name from path\n");
free(driver);
return NULL;
}
- strncpy(driver->name, devname, sizeof(driver->name));
- driver->directory = sdir;
+ safestrcpy(driver->path, path);
+ if ((sysfs_remove_trailing_slash(driver->path)) != 0) {
+ dprintf("Invalid path to driver %s\n", driver->path);
+ sysfs_close_driver(driver);
+ return NULL;
+ }
return driver;
}
+
+/**
+ * sysfs_get_driver_attributes: gets list of attributes for the given driver
+ * @driver: sysfs_driver for which attributes are required
+ * returns a dlist of attributes corresponding to the driver if present
+ * NULL otherwise
+ */
+struct dlist *sysfs_get_driver_attributes(struct sysfs_driver *driver)
+{
+ if (driver == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (driver->directory == NULL) {
+ if ((open_driver_dir(driver)) == 1)
+ return NULL;
+ }
+ if (driver->directory->attributes == NULL) {
+ if ((sysfs_read_dir_attributes(driver->directory)) != 0)
+ return NULL;
+ }
+ return(driver->directory->attributes);
+}
+
+/**
+ * sysfs_refresh_driver_attributes: refreshes the driver's list of attributes
+ * @driver: sysfs_driver whose attributes to refresh
+ *
+ * NOTE: Upon return, prior references to sysfs_attributes for this driver
+ * _may_ not be valid
+ *
+ * Returns list of attributes on success and NULL on failure
+ */
+struct dlist *sysfs_refresh_driver_attributes(struct sysfs_driver *driver)
+{
+ if (driver == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+ if (driver->directory == NULL)
+ return (sysfs_get_driver_attributes(driver));
+
+ if ((sysfs_refresh_dir_attributes(driver->directory)) != 0) {
+ dprintf("Error refreshing driver attributes\n");
+ return NULL;
+ }
+ return (driver->directory->attributes);
+}
+
+/**
+ * sysfs_get_driver_attr: searches driver's attributes by name
+ * @drv: driver to look through
+ * @name: attribute name to get
+ * returns sysfs_attribute reference on success or NULL with error
+ */
+struct sysfs_attribute *sysfs_get_driver_attr(struct sysfs_driver *drv,
+ const char *name)
+{
+ struct dlist *attrlist = NULL;
+
+ if (drv == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ attrlist = sysfs_get_driver_attributes(drv);
+ if (attrlist == NULL)
+ return NULL;
+
+ return sysfs_get_directory_attribute(drv->directory, (char *)name);
+}
+
+/**
+ * sysfs_get_driver_links: gets list of links from the given driver
+ * @driver: sysfs_driver for which links list is required
+ * returns a dlist of links corresponding to the driver if present
+ * NULL otherwise
+ */
+struct dlist *sysfs_get_driver_links(struct sysfs_driver *driver)
+{
+ if (driver == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (driver->directory == NULL)
+ if ((open_driver_dir(driver)) == 1)
+ return NULL;
+
+ if (driver->directory->links == NULL)
+ if ((sysfs_read_dir_links(driver->directory)) != 0)
+ return NULL;
+
+ return(driver->directory->links);
+}
+
+/**
+ * sysfs_get_driver_devices: open up the list of devices this driver supports
+ * @driver: sysfs_driver for which devices are needed
+ * Returns dlist of devices on SUCCESS or NULL with ERROR
+ */
+struct dlist *sysfs_get_driver_devices(struct sysfs_driver *driver)
+{
+ struct sysfs_link *curlink = NULL;
+ struct sysfs_device *device = NULL;
+
+ if (driver == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (driver->devices != NULL)
+ return (driver->devices);
+
+ if (driver->directory == NULL || driver->directory->links == NULL) {
+ struct dlist *list = NULL;
+ list = sysfs_get_driver_links(driver);
+ }
+
+ if (driver->directory->links != NULL) {
+ dlist_for_each_data(driver->directory->links, curlink,
+ struct sysfs_link) {
+ device = sysfs_open_device_path(curlink->target);
+ if (device == NULL) {
+ dprintf("Error opening device at %s\n",
+ curlink->target);
+ return NULL;
+ }
+ if (driver->devices == NULL)
+ driver->devices = dlist_new_with_delete
+ (sizeof(struct sysfs_device),
+ sysfs_close_driver_device);
+ dlist_unshift_sorted(driver->devices, device,
+ sort_list);
+ }
+ }
+ return (driver->devices);
+}
+
+/**
+ * sysfs_refresh_driver_devices: Refreshes drivers list of devices
+ * @driver: sysfs_driver whose devices list needs to be refreshed
+ *
+ * NOTE: Upon return from this function, prior sysfs_device references from
+ * this driver's list of devices _may_ not be valid
+ *
+ * Returns dlist of devices on success and NULL on failure
+ */
+struct dlist *sysfs_refresh_driver_devices(struct sysfs_driver *driver)
+{
+ if (driver == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (driver->devices != NULL) {
+ dlist_destroy(driver->devices);
+ driver->devices = NULL;
+ }
+
+ if (driver->directory == NULL)
+ return (sysfs_get_driver_devices(driver));
+
+ if ((sysfs_refresh_dir_links(driver->directory)) != 0) {
+ dprintf("Error refreshing driver links\n");
+ return NULL;
+ }
+
+ return (sysfs_get_driver_devices(driver));
+}
+
+/**
+ * sysfs_get_driver_device: looks up a device from a list of driver's devices
+ * and returns its sysfs_device corresponding to it
+ * @driver: sysfs_driver on which to search
+ * @name: name of the device to search
+ * Returns a sysfs_device if found, NULL otherwise
+ */
+struct sysfs_device *sysfs_get_driver_device(struct sysfs_driver *driver,
+ const char *name)
+{
+ struct sysfs_device *device = NULL;
+ struct dlist *devlist = NULL;
+
+ if (driver == NULL || name == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ if (driver->devices == NULL) {
+ devlist = sysfs_get_driver_devices(driver);
+ if (devlist == NULL) {
+ dprintf("Error getting driver devices\n");
+ return NULL;
+ }
+ }
+ dlist_for_each_data(driver->devices, device, struct sysfs_device) {
+ if (!(strncmp(device->name, name, SYSFS_NAME_LEN)))
+ return device;
+ }
+ return NULL;
+}
+
+/**
+ * get_driver_path: looks up the bus the driver is on and builds path to
+ * the driver.
+ * @bus: bus on which to search
+ * @drv: driver to look for
+ * @path: buffer to return path to driver
+ * @psize: size of "path"
+ * Returns 0 on success and -1 on error
+ */
+static int get_driver_path(const char *bus, const char *drv,
+ char *path, size_t psize)
+{
+ if (bus == NULL || drv == NULL || path == NULL || psize == 0) {
+ errno = EINVAL;
+ return -1;
+ }
+ if (sysfs_get_mnt_path(path, psize) != 0) {
+ dprintf("Error getting sysfs mount path\n");
+ return -1;
+ }
+ safestrcatmax(path, "/", psize);
+ safestrcatmax(path, SYSFS_BUS_NAME, psize);
+ safestrcatmax(path, "/", psize);
+ safestrcatmax(path, bus, psize);
+ safestrcatmax(path, "/", psize);
+ safestrcatmax(path, SYSFS_DRIVERS_NAME, psize);
+ safestrcatmax(path, "/", psize);
+ safestrcatmax(path, drv, psize);
+ return 0;
+}
+
+/**
+ * sysfs_open_driver_attr: read the user supplied driver attribute
+ * @bus: bus on which to look
+ * @drv: driver whose attribute has to be read
+ * @attrib: Attribute to be read
+ * Returns struct sysfs_attribute on success and NULL on failure
+ *
+ * NOTE:
+ * A call to sysfs_close_attribute() is required to close the
+ * attribute returned and to free memory
+ */
+struct sysfs_attribute *sysfs_open_driver_attr(const char *bus,
+ const char *drv, const char *attrib)
+{
+ struct sysfs_attribute *attribute = NULL;
+ char path[SYSFS_PATH_MAX];
+
+ if (bus == NULL || drv == NULL || attrib == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ memset(path, 0, SYSFS_PATH_MAX);
+ if ((get_driver_path(bus, drv, path, SYSFS_PATH_MAX)) != 0) {
+ dprintf("Error getting to driver %s\n", drv);
+ return NULL;
+ }
+ safestrcat(path, "/");
+ safestrcat(path, attrib);
+ attribute = sysfs_open_attribute(path);
+ if (attribute == NULL) {
+ dprintf("Error opening attribute %s for driver %s\n",
+ attrib, drv);
+ return NULL;
+ }
+ if ((sysfs_read_attribute(attribute)) != 0) {
+ dprintf("Error reading attribute %s for driver %s\n",
+ attrib, drv);
+ sysfs_close_attribute(attribute);
+ return NULL;
+ }
+ return attribute;
+}
+
+/**
+ * sysfs_open_driver: open driver by name, given its bus
+ * @bus_name: Name of the bus
+ * @drv_name: Name of the driver
+ * Returns the sysfs_driver reference on success and NULL on failure
+ */
+struct sysfs_driver *sysfs_open_driver(const char *bus_name,
+ const char *drv_name)
+{
+ char path[SYSFS_PATH_MAX];
+ struct sysfs_driver *driver = NULL;
+
+ if (drv_name == NULL || bus_name == NULL) {
+ errno = EINVAL;
+ return NULL;
+ }
+
+ memset(path, 0, SYSFS_PATH_MAX);
+ if ((get_driver_path(bus_name, drv_name, path, SYSFS_PATH_MAX)) != 0) {
+ dprintf("Error getting to driver %s\n", drv_name);
+ return NULL;
+ }
+ driver = sysfs_open_driver_path(path);
+ if (driver == NULL) {
+ dprintf("Error opening driver at %s\n", path);
+ return NULL;
+ }
+ return driver;
+}
+