More utility functions.

Modified commands to not to use sysfs_directory

9 files changed, 370 insertions, 243 deletions

diff --git a/ChangeLog b/ChangeLog
index 178fcf9..6b5917a 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,12 @@
 
+08/28/2003 - Ananth Mavinakayanahalli <ananth@in.ibm.com>
+                * Added more utility functions to sysfsutils
+                * Modified commands to make use of the new functions
+                * Updated libsysfs.txt to reflect new structure modifications
+                * Added sysfs_open_subsystem_list() to get subsystem specific
+                        lists from the library
+                * Added sysfs_close_list() - a generic list deletion routine
+
 08/28/2003 - Daniel Stekloff <dsteklof@us.ibm.com>
                 * Added sysfs_root_device struct for modelling /sys/devices
                         path.
diff --git a/cmd/lsbus.c b/cmd/lsbus.c
index 7f92021..9b9a709 100644
--- a/cmd/lsbus.c
+++ b/cmd/lsbus.c
@@ -85,33 +85,6 @@ void remove_end_newline(unsigned char *value)
 }
 
 /**
- * print_device_children: prints out device subdirs.
- * @sdir: print this directory's subdirectories/children.
- */
-void print_device_children(struct sysfs_directory *sdir)
-{
-	if (sdir != NULL) {
-		fprintf(stdout, "\tChildren:\n");
-		if (sdir->subdirs != NULL) {
-			struct sysfs_directory *cur;
-
-			dlist_for_each_data(sdir->subdirs, cur,
-					struct sysfs_directory) {
-				fprintf(stdout, "\t\t%s\n", cur->name);
-			}
-		}	
-		if (sdir->links != NULL) {
-			struct sysfs_link *curl = NULL;
-
-			dlist_for_each_data(sdir->links, curl,
-					struct sysfs_link) {
-				fprintf(stdout, "\t\t%s\n", curl->name);
-			}
-		}
-	}
-}
-
-/**
  * isbinaryvalue: checks to see if attribute is binary or not.
  * @attr: attribute to check.
  * returns 1 if binary or 0 if not.
@@ -191,18 +164,16 @@ void print_attribute(struct sysfs_attribute *attr)
 
 /**
  * print_device_attributes: prints out device attributes.
- * @sdir: print this directory's attributes/files.
+ * @sdir: print this device's attributes/files.
  */
-void print_device_attributes(struct sysfs_directory *sdir)
+void print_device_attributes(struct dlist *attributes)
 {
-	if (sdir != NULL && sdir->attributes != NULL) {
-		struct sysfs_attribute *cur = NULL;;
+	struct sysfs_attribute *cur = NULL;;
 
-		fprintf (stdout, "\tAttributes:\n");
-		dlist_for_each_data(sdir->attributes, cur,
+	fprintf (stdout, "\tAttributes:\n");
+	dlist_for_each_data(attributes, cur,
 				struct sysfs_attribute) {
-			print_attribute(cur);
-		}
+		print_attribute(cur);
 	}
 }
 
@@ -212,16 +183,16 @@ void print_device_attributes(struct sysfs_directory *sdir)
  */
 void print_device(struct sysfs_device *device)
 {
-	if (device != NULL && device->directory != NULL) {
-		fprintf (stdout, "  %s %s\n", device->bus_id, device->name);
-		if (device->directory->subdirs != NULL
-		    || device->directory->links != NULL)
-			print_device_children(device->directory);
-		if (device->directory->attributes != NULL && (show_options 
-		    & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
-		    | SHOW_ALL_ATTRIB_VALUES))) 
-			print_device_attributes(device->directory);
-		if (device->driver_name != NULL) 
+	struct dlist *attributes = NULL;
+	
+	if (device != NULL) {
+		fprintf (stdout, "  %s\n", device->bus_id);
+		if (show_options & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
+		    | SHOW_ALL_ATTRIB_VALUES)) 
+			attributes = sysfs_get_device_attributes(device);
+			if (attributes != NULL)
+				print_device_attributes(attributes);
+		if (isalnum(device->driver_name[0])) 
 			fprintf (stdout, "\tDriver: %s\n", 
 						device->driver_name);
 	}
@@ -233,14 +204,15 @@ void print_device(struct sysfs_device *device)
  */
 void print_driver_attributes(struct sysfs_driver *driver)
 {
-	if (driver != NULL && driver->directory != NULL) {
-		struct sysfs_directory *sdir = driver->directory;
-
-		if (sdir->attributes != NULL) {
+	struct dlist *attributes = NULL;
+	
+	if (driver != NULL) {
+		attributes = sysfs_get_driver_attributes(driver);
+		if (attributes != NULL) {
 			struct sysfs_attribute *cur = NULL;
 
 			fprintf (stdout, "\t%s Attributes:\n", driver->name);
-			dlist_for_each_data(sdir->attributes, cur, 
+			dlist_for_each_data(attributes, cur, 
 					struct sysfs_attribute) {
 				print_attribute(cur);
 			}
@@ -254,17 +226,14 @@ void print_driver_attributes(struct sysfs_driver *driver)
  */
 void print_driver_devices(struct sysfs_driver *driver)
 {
-	if (driver != NULL && driver->directory != NULL) {
-		struct sysfs_directory *sdir = driver->directory;
-
-		if (sdir->links != NULL) {
-			struct sysfs_link *cur = NULL;
-
+	struct sysfs_device *device = NULL;
+	
+	if (driver != NULL) {
+		if (driver->devices != NULL) {
 			fprintf (stdout, "\tDevices:\n");
-			dlist_for_each_data(sdir->links, cur,
-					struct sysfs_link) {
-				fprintf(stdout, "\t\t%s\n", cur->name);
-			}
+			dlist_for_each_data(driver->devices, device,
+					struct sysfs_device) 
+				fprintf(stdout, "\t\t%s\n", device->bus_id);
 		}
 	}
 }
@@ -275,19 +244,14 @@ void print_driver_devices(struct sysfs_driver *driver)
  */
 void print_driver(struct sysfs_driver *driver)
 {
-	struct sysfs_directory *sdir = NULL;
-
+	struct dlist *links = NULL, *attributes = NULL;
+	
 	if (driver != NULL) {
 		fprintf (stdout, "  %s\n", driver->name);
-		sdir = driver->directory;
-		if (sdir != NULL) {
-			if (sdir->links != NULL)
-				print_driver_devices(driver);
-			if(sdir->attributes != NULL && (show_options
-			    & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
-			    | SHOW_ALL_ATTRIB_VALUES)))
-				print_driver_attributes(driver);
-		}
+		print_driver_devices(driver);
+		if(show_options & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
+			    | SHOW_ALL_ATTRIB_VALUES))
+			print_driver_attributes(driver);
 	}
 }
 
@@ -319,7 +283,7 @@ int print_sysfs_bus(unsigned char *busname)
 		dlist_for_each_data(bus->devices, curdev,
 				struct sysfs_device) {
 			if (bus_device == NULL || (strcmp(bus_device,
-			    curdev->bus_id) == 0))
+			    curdev->bus_id) == 0)) 
 				print_device(curdev);
 		}
 	}
@@ -340,35 +304,20 @@ int print_sysfs_bus(unsigned char *busname)
  */
 int print_sysfs_buses(void)
 {
-	struct sysfs_directory *busdir = NULL, *current = NULL;
-	unsigned char buspath[SYSFS_PATH_MAX];
-	int ret = 0;
-
-	/* get sysfs mount point */
-	if ((sysfs_get_mnt_path(buspath, SYSFS_PATH_MAX) != 0)) {
-		perror("sysfs_get_mnt_path");
-		fprintf(stderr, "Error getting sysfs mount path - exiting\n");
-		exit(1);
-	}
-	strcat(buspath, SYSFS_BUS_DIR);
-	busdir = sysfs_open_directory(buspath);
-	if (busdir == NULL) {
-		fprintf(stderr, "Error opening sysfs bus directory at %s\n",
-			buspath);
-		return 1;
-	}
-	if ((sysfs_read_directory(busdir)) != 0) {
-		fprintf(stderr, "Error reading sysfs bus directory at %s\n",
-			buspath);
-		sysfs_close_directory(busdir);
-		return 1;
-	}
-
-	fprintf(stdout, "Supported sysfs buses:\n");
-	dlist_for_each_data(busdir->subdirs, current, struct sysfs_directory) {
-		fprintf(stdout, "\t%s\n", current->name);
+        unsigned char subsys[SYSFS_NAME_LEN];
+        struct dlist *list = NULL;
+        char *cur = NULL;
+        int ret = 0;
+
+        strcpy(subsys, SYSFS_BUS_DIR);
+        list = sysfs_open_subsystem_list(subsys);
+        if (list != NULL) {
+		fprintf(stdout, "Supported sysfs buses:\n");
+		dlist_for_each_data(list, cur, char)
+			fprintf(stdout, "\t%s\n", cur);
 	}
-	sysfs_close_directory(busdir);
+	sysfs_close_list(list);
+									
 	return ret;
 }
 
diff --git a/cmd/systool.c b/cmd/systool.c
index 7d482e0..fe5e903 100644
--- a/cmd/systool.c
+++ b/cmd/systool.c
@@ -103,30 +103,19 @@ void remove_end_newline(unsigned char *value)
 
 /**
  * show_device_children: prints out device subdirs.
- * @sdir: print this directory's subdirectories/children.
+ * @children: dlist of child devices.
  */
-void show_device_children(struct sysfs_directory *sdir, int level)
+void show_device_children(struct dlist *children, int level)
 {
-	if (sdir != NULL) {
+	struct sysfs_device *child = NULL;
+	
+	if (children != NULL) {
 		indent(level);
 		fprintf(stdout, "Children:\n");
-		if (sdir->subdirs != NULL) {
-			struct sysfs_directory *cur;
-		
-			dlist_for_each_data(sdir->subdirs, cur, 
-					struct sysfs_directory) {
-				indent(level+4);
-				fprintf(stdout, "%s\n", cur->name);
-			}
-		}
-		if (sdir->links != NULL) {
-			struct sysfs_link *curl = NULL;
-			
-			dlist_for_each_data(sdir->links, curl,
-					struct sysfs_link) {
-				indent(level+4);
-				fprintf(stdout, "%s\n", curl->name);
-			}
+		dlist_for_each_data(children, child, 
+				struct sysfs_device) {
+			indent(level+4);
+			fprintf(stdout, "%s\n", child->bus_id);
 		}
 	}
 }
@@ -213,17 +202,17 @@ void show_attribute(struct sysfs_attribute *attr, int level)
 }
 
 /**
- * show_attributes: prints out a directory's attributes.
- * @sdir: print this directory's attributes/files.
+ * show_attributes: prints out a list of attributes.
+ * @attributes: print this dlist of attributes/files.
  */
-void show_attributes(struct sysfs_directory *sdir, int level)
+void show_attributes(struct dlist *attributes, int level)
 {
-	if (sdir != NULL && sdir->attributes != NULL) {
+	if (attributes != NULL) {
 		struct sysfs_attribute *cur = NULL;
-
+		
 		indent(level);
 		fprintf (stdout, "Attributes:\n");
-		dlist_for_each_data(sdir->attributes, cur, 
+		dlist_for_each_data(attributes, cur, 
 				struct sysfs_attribute) {
 			show_attribute(cur, (level+4));
 		}
@@ -236,16 +225,19 @@ void show_attributes(struct sysfs_directory *sdir, int level)
  */
 void show_device(struct sysfs_device *device, int level)
 {
-	if (device != NULL && device->directory != NULL) {
+	struct dlist *attributes = NULL;
+	
+	if (device != NULL) {
 		indent(level);
-		fprintf (stdout, "%s %s\n", device->bus_id, device->name);
-		if (device->directory->subdirs != NULL
-		    || device->directory->links != NULL)
-			show_device_children(device->directory, (level+4));
-		if (device->directory->attributes != NULL && (show_options 
-		    & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
-		    | SHOW_ALL_ATTRIB_VALUES))) 
-			show_attributes(device->directory, (level+4));
+		fprintf (stdout, "%s\n", device->bus_id);
+		if (device->children != NULL)
+			show_device_children(device->children, (level+4));
+		if (show_options & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
+		    | SHOW_ALL_ATTRIB_VALUES)) {
+			attributes = sysfs_get_device_attributes(device);
+			if (attributes != NULL)
+				show_attributes(attributes, (level+4));
+		}
 		if (isalnum(device->driver_name[0])) {
 			indent(level+4);
 			fprintf (stdout, "Driver: %s\n", 
@@ -260,13 +252,16 @@ void show_device(struct sysfs_device *device, int level)
  */
 void show_root_device(struct sysfs_device *device, int level)
 {
-	if (device != NULL && device->directory != NULL) {
+	if (device != NULL) {
 		indent(level);
-		fprintf (stdout, "%s %s\n", device->bus_id, device->name);
-		if (device->directory->attributes != NULL && (show_options 
-		    & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
-		    | SHOW_ALL_ATTRIB_VALUES)))
-			show_attributes(device->directory, (level+4));
+		fprintf (stdout, "%s\n", device->bus_id);
+		if (show_options & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
+		    | SHOW_ALL_ATTRIB_VALUES)) {
+			struct dlist *attributes = NULL;
+			attributes = sysfs_get_device_attributes(device);
+			if (attributes != NULL)
+				show_attributes(attributes, (level+4));
+		}
 	}
 }
 
@@ -276,15 +271,16 @@ void show_root_device(struct sysfs_device *device, int level)
  */
 void show_driver_attributes(struct sysfs_driver *driver, int level)
 {
-	if (driver != NULL && driver->directory != NULL) {
-		struct sysfs_directory *sdir = driver->directory;
-
-		if (sdir->attributes != NULL) {
+	if (driver != NULL) {
+		struct dlist *attributes = NULL;
+		
+		attributes = sysfs_get_driver_attributes(driver);
+		if (attributes != NULL) {
 			struct sysfs_attribute *cur = NULL;
 
 			indent(level);
 			fprintf (stdout, "%s Attributes:\n", driver->name);
-			dlist_for_each_data(sdir->attributes, cur,
+			dlist_for_each_data(attributes, cur,
 					struct sysfs_attribute) {
 				show_attribute(cur, (level+4));
 			}
@@ -298,18 +294,16 @@ void show_driver_attributes(struct sysfs_driver *driver, int level)
  */
 void show_driver_devices(struct sysfs_driver *driver, int level)
 {
-	if (driver != NULL && driver->directory != NULL) {
-		struct sysfs_directory *sdir = driver->directory;
-
-		if (sdir->links != NULL) {
-			struct sysfs_link *cur = NULL;
+	if (driver != NULL) {
+		if (driver->devices != NULL) {
+			struct sysfs_device *cur = NULL;
 
 			indent(level);
 			fprintf (stdout, "Devices:\n");
-			dlist_for_each_data(sdir->links, cur,
-					struct sysfs_link) {
+			dlist_for_each_data(driver->devices, cur,
+					struct sysfs_device) {
 				indent(level+4);
-				fprintf (stdout, "%s\n", cur->name);
+				fprintf (stdout, "%s\n", cur->bus_id);
 			}
 		}
 	}
@@ -321,20 +315,15 @@ void show_driver_devices(struct sysfs_driver *driver, int level)
  */
 void show_driver(struct sysfs_driver *driver, int level)
 {
-	struct sysfs_directory *sdir = NULL;
-
 	if (driver != NULL) {
 		indent(level);
 		fprintf (stdout, "%s\n", driver->name);
-		sdir = driver->directory;
-		if (sdir != NULL) {
-			if (sdir->links != NULL)
-				show_driver_devices(driver, (level+4));
-			if(sdir->attributes != NULL && (show_options
-			    & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
-			    | SHOW_ALL_ATTRIB_VALUES)))
-				show_driver_attributes(driver, (level+4));
-		}
+		if (driver->devices != NULL) 
+			show_driver_devices(driver, (level+4));
+			
+		if (show_options & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
+			    | SHOW_ALL_ATTRIB_VALUES))
+			show_driver_attributes(driver, (level+4));
 	}
 }
 
@@ -407,27 +396,20 @@ int show_sysfs_bus(unsigned char *busname)
  */
 void show_class_device(struct sysfs_class_device *dev, int level)
 {
-	struct sysfs_directory *cur = NULL;
-
+	struct dlist *attributes = NULL;
+	
 	if (dev != NULL) {
 		indent(level);
 		fprintf(stdout, "%s\n", dev->name);
-		if (dev->directory != NULL && (show_options
-		    & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
-		    | SHOW_ALL_ATTRIB_VALUES))) {
-			show_attributes(dev->directory, (level+4));
-			if (dev->directory->subdirs == NULL)
-				return;
-			dlist_for_each_data(dev->directory->subdirs, cur,
-					struct sysfs_directory) {
-				indent(level+4);
-				fprintf(stdout, "%s\n", cur->name);
-				show_attributes(cur, (level+4));
-			}
-		}
-		if (dev->sysdevice != NULL && (show_options & SHOW_DEVICES))
+		if (show_options & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
+		    | SHOW_ALL_ATTRIB_VALUES)) {
+			attributes = sysfs_get_classdev_attributes(dev);
+			if (attributes != NULL)
+				show_attributes(attributes, (level+4));
+		} 
+		if (dev->sysdevice != NULL && (show_options & SHOW_DEVICES)) 
 			show_device(dev->sysdevice, (level+4));
-		if (dev->driver != NULL && (show_options & SHOW_DRIVERS))
+		if (dev->driver != NULL && (show_options & SHOW_DRIVERS)) 
 			show_driver(dev->driver, (level+4));
 	}
 }
@@ -502,37 +484,6 @@ int show_sysfs_root(unsigned char *rootname)
 	return 0;
 }
 
-/**
- * show_subdirectories: prints all subdirectory names at path
- * @path: sysfs path where subdirs are.
- * returns 0 with success or 1 with error.
- */
-int show_subdirectories(unsigned char *path, int level)
-{
-	struct sysfs_directory *dir = NULL, *current = NULL;
-	int ret = 0;
-
-	dir = sysfs_open_directory(path);
-	if (dir == NULL) {
-		fprintf(stderr, "Error opening sysfs directory at %s\n", path);
-		return 1;
-	}
-	if ((sysfs_read_directory(dir)) != 0) {
-		fprintf(stderr, "Error reading sysfs directory at %s\n", path);
-		sysfs_close_directory(dir);
-		return 1;
-	}
-
-	if (dir->subdirs != NULL) {
-		dlist_for_each_data(dir->subdirs, current, 
-				struct sysfs_directory) {
-			indent(level);
-			fprintf(stdout, "%s\n", current->name);
-		}
-	}
-	sysfs_close_directory(dir);
-	return ret;
-}
 
 /**
  * show_default_info: prints current buses, classes, and root devices
@@ -541,42 +492,41 @@ int show_subdirectories(unsigned char *path, int level)
  */
 int show_default_info(void)
 {
-	unsigned char sysfs_root[SYSFS_PATH_MAX];
-	unsigned char path_to_print[SYSFS_PATH_MAX];
+	unsigned char subsys[SYSFS_NAME_LEN];
+	struct dlist *list = NULL;
+	char *cur = NULL;
 	int retval = 0;
 
-	/* get sysfs mount point */
-	if (sysfs_get_mnt_path(sysfs_root, SYSFS_PATH_MAX) != 0) {
-		perror("sysfs_get_mnt_path");
-		fprintf(stderr, "Error getting sysfs mount point\n");
-		exit(1);
+	strcpy(subsys, SYSFS_BUS_DIR);
+	list = sysfs_open_subsystem_list(subsys);
+	if (list != NULL) {
+		fprintf(stdout, "Supported sysfs buses:\n");
+		dlist_for_each_data(list, cur, char)
+			fprintf(stdout, "\t%s\n", cur);
 	}
-	strcpy(path_to_print, sysfs_root);
+	sysfs_close_list(list);
 
-	/* print supported buses */
-	strcat(path_to_print, SYSFS_BUS_DIR);
-	fprintf(stdout, "Supported sysfs buses:\n");
-	retval = show_subdirectories(path_to_print, 4);
-
-	if (retval == 0) {
-		/* print supported classes */
-		strcpy(path_to_print, sysfs_root);
-		strcat(path_to_print, SYSFS_CLASS_DIR);
+	strcpy(subsys, SYSFS_CLASS_DIR);
+	list = sysfs_open_subsystem_list(subsys);
+	if (list != NULL) {
 		fprintf(stdout, "Supported sysfs classes:\n");
-		retval = show_subdirectories(path_to_print, 4);
+		dlist_for_each_data(list, cur, char)
+			fprintf(stdout, "\t%s\n", cur);
 	}
-
-	if (retval == 0) {
-		/* print supported root devices */
-		strcpy(path_to_print, sysfs_root);
-		strcat(path_to_print, SYSFS_DEVICES_DIR);
-		fprintf(stdout, "Supported sysfs root devices:\n");
-		retval = show_subdirectories(path_to_print, 4);
+	sysfs_close_list(list);
+
+	strcpy(subsys, SYSFS_DEVICES_DIR);
+	list = sysfs_open_subsystem_list(subsys);
+	if (list != NULL) {
+		fprintf(stdout, "Supported sysfs devices:\n");
+		dlist_for_each_data(list, cur, char)
+			fprintf(stdout, "\t%s\n", cur);
 	}
-
+	sysfs_close_list(list);
+			
 	return retval;
 }
-
+	
 /* MAIN */
 int main(int argc, char *argv[])
 {
diff --git a/include/libsysfs.h b/include/libsysfs.h
index ffeb916..9a3eb66 100644
--- a/include/libsysfs.h
+++ b/include/libsysfs.h
@@ -140,6 +140,8 @@ extern int sysfs_get_name_from_path(const unsigned char *path,
 					unsigned char *name, size_t len);
 extern int sysfs_get_link(const unsigned char *path, unsigned char *target, 
 								size_t len);
+extern struct dlist *sysfs_open_subsystem_list(unsigned char *name);
+extern void sysfs_close_list(struct dlist *list);
 
 /* sysfs directory and file access */
 extern void sysfs_close_attribute(struct sysfs_attribute *sysattr);
@@ -170,6 +172,8 @@ extern struct sysfs_attribute *sysfs_get_directory_attribute
 /* sysfs driver access */
 extern void sysfs_close_driver(struct sysfs_driver *driver);
 extern struct sysfs_driver *sysfs_open_driver(const unsigned char *path);
+extern struct dlist *sysfs_get_driver_attributes(struct sysfs_driver *driver);
+extern struct dlist *sysfs_get_driver_links(struct sysfs_driver *driver);
 
 /* generic sysfs device access */
 extern void sysfs_close_root_device(struct sysfs_root_device *root);
@@ -181,6 +185,7 @@ extern struct sysfs_device *sysfs_open_device(const unsigned char *path);
 extern struct sysfs_device *sysfs_open_device_tree(const unsigned char *path);
 extern struct sysfs_attribute *sysfs_get_device_attr
 			(struct sysfs_device *dev, const unsigned char *name);
+extern struct dlist *sysfs_get_device_attributes(struct sysfs_device *device);
 
 /* generic sysfs bus access */
 extern void sysfs_close_bus(struct sysfs_bus *bus);
@@ -203,6 +208,12 @@ extern struct sysfs_class_device *sysfs_open_class_device
 					(const unsigned char *path);
 extern void sysfs_close_class(struct sysfs_class *cls);
 extern struct sysfs_class *sysfs_open_class(const unsigned char *name);
+extern struct sysfs_class_device *sysfs_get_class_device
+	(struct sysfs_class *class, unsigned char *name);
+extern struct sysfs_class_device *sysfs_open_class_device_by_name
+	(unsigned char *class, unsigned char *name);
+extern struct dlist *sysfs_get_classdev_attributes
+	(struct sysfs_class_device *cdev);
 
 #ifdef __cplusplus
 }
diff --git a/lib/sysfs_class.c b/lib/sysfs_class.c
index 3b34c79..c93428a 100644
--- a/lib/sysfs_class.c
+++ b/lib/sysfs_class.c
@@ -29,6 +29,23 @@ void sysfs_close_cls_dev(void *dev)
 }
 
 /**
+ * class_name_equal: compares class_devices' name
+ * @a: class_name looking for
+ * @b: sysfs_class_device being compared
+ */
+static int class_name_equal(void *a, void *b)
+{
+	if (a == NULL || b == NULL)
+		return 0;
+
+	if (strcmp(((unsigned char *)a), ((struct sysfs_class_device *)b)->name)
+		== 0)
+		return 1;
+
+	return 0;
+}
+
+/**
  * sysfs_close_class_device: closes a single class device.
  * @dev: class device to close.
  */
@@ -268,3 +285,78 @@ struct sysfs_class *sysfs_open_class(const unsigned char *name)
 
 	return cls;
 }
+
+/**
+ * sysfs_get_class_device: Get specific class device using the device's id
+ * @class: class to find device on
+ * @name: class name of the device
+ */ 
+struct sysfs_class_device *sysfs_get_class_device(struct sysfs_class *class,
+					unsigned char *name)
+{
+	if (class == NULL || name == NULL) {
+		errno = EINVAL;
+		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.
+ * Class_device must be closed using sysfs_close_class_device
+ * @classname: Class to search
+ * @name: name of the class_device
+ */
+struct sysfs_class_device *sysfs_open_class_device_by_name
+		(unsigned char *classname, unsigned char *name)
+{
+	struct sysfs_class *class = NULL;
+	struct sysfs_class_device *cdev = NULL, *rcdev = 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);
+		return NULL;
+	}
+
+	cdev = sysfs_get_class_device(class, name);
+	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;
+}
+
+
+/**
+ * sysfs_get_classdev_attributes: returns a dlist of attributes for
+ * 	the requested class_device
+ * @cdev: sysfs_class_dev for which attributes are needed
+ * returns a dlist of attributes if exists, NULL otherwise
+ */
+struct dlist *sysfs_get_classdev_attributes(struct sysfs_class_device *cdev)
+{
+	if (cdev == NULL || cdev->directory == NULL)
+		return NULL;
+
+	return (cdev->directory->attributes);
+}
diff --git a/lib/sysfs_device.c b/lib/sysfs_device.c
index c68a987..7e18e23 100644
--- a/lib/sysfs_device.c
+++ b/lib/sysfs_device.c
@@ -331,3 +331,16 @@ struct sysfs_root_device *sysfs_open_root_device(const unsigned char *name)
 
 	return root;
 }
+
+/**
+ * sysfs_get_device_attributes: returns a dlist of attributes corresponding to
+ * 	the specific device
+ * @device: struct sysfs_device * for which attributes are to be returned
+ */
+struct dlist *sysfs_get_device_attributes(struct sysfs_device *device)
+{
+	if (device == NULL || device->directory == NULL) 
+		return NULL;
+
+	return (device->directory->attributes);
+}	
diff --git a/lib/sysfs_dir.c b/lib/sysfs_dir.c
index c75193e..4c271cc 100644
--- a/lib/sysfs_dir.c
+++ b/lib/sysfs_dir.c
@@ -28,7 +28,7 @@
  */
 static void sysfs_del_attribute(void *attr)
 {
-	        sysfs_close_attribute((struct sysfs_attribute *)attr);
+        sysfs_close_attribute((struct sysfs_attribute *)attr);
 }
 
 /**
@@ -36,7 +36,7 @@ static void sysfs_del_attribute(void *attr)
  */
 static void sysfs_del_link(void *ln)
 {
-	        sysfs_close_link((struct sysfs_link *)ln);
+        sysfs_close_link((struct sysfs_link *)ln);
 }
 
 /**
@@ -44,7 +44,7 @@ static void sysfs_del_link(void *ln)
  */
 static void sysfs_del_directory(void *dir)
 {
-	        sysfs_close_directory((struct sysfs_directory *)dir);
+        sysfs_close_directory((struct sysfs_directory *)dir);
 }
 
 /**
diff --git a/lib/sysfs_driver.c b/lib/sysfs_driver.c
index 04b2b17..c1a6268 100644
--- a/lib/sysfs_driver.c
+++ b/lib/sysfs_driver.c
@@ -86,3 +86,31 @@ struct sysfs_driver *sysfs_open_driver(const unsigned char *path)
 	
 	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 || driver->directory == NULL)
+		return NULL;
+
+	return(driver->directory->attributes);
+}
+
+/**
+ * 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 || driver->directory == NULL)
+		return NULL;
+
+	return(driver->directory->links);
+}
diff --git a/lib/sysfs_utils.c b/lib/sysfs_utils.c
index d4c085b..16a2d77 100644
--- a/lib/sysfs_utils.c
+++ b/lib/sysfs_utils.c
@@ -154,3 +154,79 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
 
 	return 0;
 }
+
+
+/**
+ * sysfs_del_name: free function for sysfs_open_subsystem_list
+ * @name: memory area to be freed
+ */ 
+void sysfs_del_name(void *name)
+{
+	free(name);
+}
+
+
+/**
+ * sysfs_close_list: generic list free routine
+ * @list: dlist to free
+ * Returns nothing
+ */
+void sysfs_close_list(struct dlist *list)
+{
+	if (list != NULL)
+		dlist_destroy(list);
+}
+
+/**
+ * sysfs_open_subsystem_list: gets a list of all supported "name" subsystem
+ * 	details from the system
+ * @name: name of the subsystem, eg., "bus", "class", "devices"
+ * Returns a dlist of supported names or NULL if subsystem not supported
+ */ 
+struct dlist *sysfs_open_subsystem_list(unsigned char *name)
+{
+	unsigned char sysfs_path[SYSFS_PATH_MAX], *subsys_name = NULL;
+	struct sysfs_directory *dir = NULL, *cur = NULL;
+	struct dlist *list = NULL;
+	
+	if (name == NULL)
+		return NULL;
+
+	if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
+		dprintf("Error getting sysfs mount point\n");
+		return NULL;
+	}
+
+	strcat(sysfs_path, name);
+	dir = sysfs_open_directory(sysfs_path);
+	if (dir == NULL) {
+		dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
+		return NULL;
+	}
+
+	if (sysfs_read_directory(dir) != 0) {
+		dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
+		sysfs_close_directory(dir);
+		return NULL;
+	}
+
+	if (dir->subdirs != NULL) {
+		list = dlist_new_with_delete(SYSFS_NAME_LEN,
+				sysfs_del_name);
+		if (list == NULL) {
+			dprintf("Error creating list\n");
+			sysfs_close_directory(dir);
+			return NULL;
+		}
+
+		dlist_for_each_data(dir->subdirs, cur,
+				struct sysfs_directory) {
+			subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
+			strcpy(subsys_name, cur->name);
+			dlist_unshift(list, subsys_name);
+		}
+	}
+	sysfs_close_directory(dir);
+	return list;
+}
+