Integrated Eric J Bohm's dlist stuff

Modified library to use dlists
Added few "find" functions

22 files changed, 1947 insertions, 505 deletions

diff --git a/CREDITS b/CREDITS
index bcd0e38..7d95c13 100644
--- a/CREDITS
+++ b/CREDITS
@@ -6,3 +6,6 @@ have made contributions:
 		- Supplied libsysfs code cleanup including code
 			simplification, read-only strings, and
 			C++ compatibility.
+	o Eric J Bohm <bohm@gate.csgeeks.org>:
+		- Supplied dlist generic linked list implementation.
+		- Added dlist_for_each* functionality.
diff --git a/ChangeLog b/ChangeLog
index 10c0e53..48f19c2 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,13 @@
 
+08/19/2003 - Daniel Stekloff <dsteklof@us.ibm.com>
+               * Integrated Eric Bohm's dlist patch
+               * Integrated Eric Bohm's follow on patch adding dlist_for_each
+               * Changed chars to unsigned chars
+               * Reworked structures to be neater and to contain
+                       sysfs_directories as private structures
+               * Added more functions for retrieving data like attributes
+               * Added some find functions
+
 08/06/2003 - Ananth Mavinakayanahalli <ananth@in.ibm.com>
 		* Patch to correct dprintf usage
 
diff --git a/Makefile.am b/Makefile.am
index 9ccb34f..ead8a23 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,5 +1,5 @@
 EXTRA_DIST = docs include
-SUBDIRS = lib cmd
+SUBDIRS = lib cmd test
 
 dist-hook:
 	rm -rf `find $(distdir)/docs -name CVS`
diff --git a/Makefile.in b/Makefile.in
index 48b8a7b..27391fd 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -76,7 +76,7 @@ am__include = @am__include@
 am__quote = @am__quote@
 install_sh = @install_sh@
 EXTRA_DIST = docs include
-SUBDIRS = lib cmd
+SUBDIRS = lib cmd test
 subdir = .
 ACLOCAL_M4 = $(top_srcdir)/aclocal.m4
 mkinstalldirs = $(SHELL) $(top_srcdir)/mkinstalldirs
diff --git a/cmd/lsbus.c b/cmd/lsbus.c
index c709e31..2a98150 100644
--- a/cmd/lsbus.c
+++ b/cmd/lsbus.c
@@ -34,8 +34,8 @@
 
 /* Command Options */
 static int show_options = 0;		/* bitmask of show options */
-static char *attr_to_show = NULL;	/* print value for this attribute */
-static char *bus_device = NULL;		/* print only this bus device */
+static unsigned char *attr_to_show = NULL;	/* print value for this attribute*/
+static unsigned char *bus_device = NULL;		/* print only this bus device */
 
 #define SHOW_ATTRIBUTES		0x01	/* show attributes command option */
 #define SHOW_ATTRIBUTE_VALUE	0x02	/* show an attribute value option */
@@ -45,13 +45,13 @@ static char *bus_device = NULL;		/* print only this bus device */
                                                                                 
 #define SHOW_ALL		0xff
 
-static char cmd_options[] = "aA:dDhv";
+static unsigned char cmd_options[] = "aA:dDhv";
 
 /*
  * binary_files - defines existing sysfs binary files that should be printed
  * in hex.
  */
-static char *binary_files[] = {
+static unsigned char *binary_files[] = {
 	"config",
 	"data"
 };
@@ -76,9 +76,9 @@ void usage(void)
  * remove_end_newline: removes newline on the end of an attribute value
  * @value: string to remove newline from
  */
-void remove_end_newline(char *value)
+void remove_end_newline(unsigned char *value)
 {
-	char *p = value + (strlen(value) - 1);
+	unsigned char *p = value + (strlen(value) - 1);
 
 	if (p != NULL && *p == '\n')
 		*p = '\0';
@@ -93,24 +93,19 @@ void print_device_children(struct sysfs_directory *sdir)
 	if (sdir != NULL) {
 		fprintf(stdout, "\tChildren:\n");
 		if (sdir->subdirs != NULL) {
-			char dirname[SYSFS_NAME_LEN];
-			struct sysfs_directory *cur = sdir->subdirs;
-
-			while (cur != NULL) {
-				if ((sysfs_get_name_from_path(cur->path, 
-				     dirname, SYSFS_NAME_LEN)) == 0)
-					fprintf(stdout, "\t\t%s\n", dirname);
-				else
-					fprintf(stdout, "\t\t%s\n", cur->path);
-				cur = cur->next;
+			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 = sdir->links;
-			
-			while(curl != NULL) {
+			struct sysfs_link *curl = NULL;
+
+			dlist_for_each_data(sdir->links, curl,
+					struct sysfs_link) {
 				fprintf(stdout, "\t\t%s\n", curl->name);
-				curl = curl->next;
 			}
 		}
 	}
@@ -123,17 +118,13 @@ void print_device_children(struct sysfs_directory *sdir)
  */
 int isbinaryvalue(struct sysfs_attribute *attr)
 {
-	char attrname[SYSFS_NAME_LEN];
 	int i;
 
 	if (attr == NULL || attr->value == NULL)
 		return 0;
-	if ((sysfs_get_name_from_path(attr->path, attrname, SYSFS_NAME_LEN))
-	    != 0)
-		return 0;
 
 	for (i = 0; i < binfiles; i++) 
-		if ((strcmp(attrname, binary_files[i])) == 0)
+		if ((strcmp(attr->name, binary_files[i])) == 0)
 			return 1;
 
 	return 0;
@@ -178,25 +169,19 @@ void print_attribute_value(struct sysfs_attribute *attr)
  */
 void print_attribute(struct sysfs_attribute *attr)
 {
-	char attrname[SYSFS_NAME_LEN];
-
 	if (attr == NULL) 
 		return;
 
-	if ((sysfs_get_name_from_path(attr->path, attrname, SYSFS_NAME_LEN)) 
-	    != 0)
-		return; 
-
 	if (show_options & SHOW_ALL_ATTRIB_VALUES) {
-		fprintf(stdout, "\t\t%s", attrname);
+		fprintf(stdout, "\t\t%s", attr->name);
 		print_attribute_value(attr);
 
 	} else if ((show_options & SHOW_ATTRIBUTES) || ((show_options 
-	    & SHOW_ATTRIBUTE_VALUE) && (strcmp(attrname, attr_to_show) 
+	    & SHOW_ATTRIBUTE_VALUE) && (strcmp(attr->name, attr_to_show) 
 	    == 0))) {
-		fprintf (stdout, "\t\t%s", attrname);
+		fprintf (stdout, "\t\t%s", attr->name);
 		if (show_options & SHOW_ATTRIBUTE_VALUE && attr->value != NULL
-		    && (strcmp(attrname, attr_to_show)) == 0) {
+		    && (strcmp(attr->name, attr_to_show)) == 0) {
 			print_attribute_value(attr);
 		} else {
 			fprintf(stdout, "\n");
@@ -211,12 +196,12 @@ void print_attribute(struct sysfs_attribute *attr)
 void print_device_attributes(struct sysfs_directory *sdir)
 {
 	if (sdir != NULL && sdir->attributes != NULL) {
-		struct sysfs_attribute *cur = sdir->attributes;
+		struct sysfs_attribute *cur = NULL;;
 
 		fprintf (stdout, "\tAttributes:\n");
-		while (cur != NULL) {
+		dlist_for_each_data(sdir->attributes, cur,
+				struct sysfs_attribute) {
 			print_attribute(cur);
-			cur = cur->next;
 		}
 	}
 }
@@ -252,12 +237,12 @@ void print_driver_attributes(struct sysfs_driver *driver)
 		struct sysfs_directory *sdir = driver->directory;
 
 		if (sdir->attributes != NULL) {
-			struct sysfs_attribute *cur = sdir->attributes;
+			struct sysfs_attribute *cur = NULL;
 
 			fprintf (stdout, "\t%s Attributes:\n", driver->name);
-			while (cur != NULL) {
+			dlist_for_each_data(sdir->attributes, cur, 
+					struct sysfs_attribute) {
 				print_attribute(cur);
-				cur = cur->next;
 			}
 		}
 	}
@@ -273,12 +258,12 @@ void print_driver_devices(struct sysfs_driver *driver)
 		struct sysfs_directory *sdir = driver->directory;
 
 		if (sdir->links != NULL) {
-			struct sysfs_link *cur = sdir->links;
+			struct sysfs_link *cur = NULL;
 
 			fprintf (stdout, "\tDevices:\n");
-			while (cur != NULL) {
+			dlist_for_each_data(sdir->links, cur,
+					struct sysfs_link) {
 				fprintf(stdout, "\t\t%s\n", cur->name);
-				cur = cur->next;
 			}
 		}
 	}
@@ -311,7 +296,7 @@ void print_driver(struct sysfs_driver *driver)
  * @busname: bus to print.
  * returns 0 with success or 1 with error.
  */
-int print_sysfs_bus(char *busname)
+int print_sysfs_bus(unsigned char *busname)
 {
 	struct sysfs_bus *bus = NULL;
 	struct sysfs_device *curdev = NULL;
@@ -329,22 +314,19 @@ int print_sysfs_bus(char *busname)
 
 	fprintf(stdout, "Bus: %s\n", busname);
 	if (bus->devices != NULL && (show_options & SHOW_DEVICES)) {
-		curdev = bus->devices;
 		if (bus_device == NULL)
 			fprintf(stdout, "Devices:\n");
-		while (curdev != NULL) {
+		dlist_for_each_data(bus->devices, curdev,
+				struct sysfs_device) {
 			if (bus_device == NULL || (strcmp(bus_device,
 			    curdev->bus_id) == 0))
 				print_device(curdev);
-			curdev = curdev->next;
 		}
 	}
 	if (bus->drivers != NULL && (show_options & SHOW_DRIVERS)) {
-		curdrv = bus->drivers;
 		fprintf(stdout, "Drivers:\n");
-		while (curdrv != NULL) {
+		dlist_for_each_data(bus->drivers, curdrv, struct sysfs_driver) {
 			print_driver(curdrv);
-			curdrv = curdrv->next;
 		}
 	}
 	sysfs_close_bus(bus);
@@ -359,8 +341,7 @@ int print_sysfs_bus(char *busname)
 int print_sysfs_buses(void)
 {
 	struct sysfs_directory *busdir = NULL, *current = NULL;
-	char busname[SYSFS_NAME_LEN];
-	char buspath[SYSFS_PATH_MAX];
+	unsigned char buspath[SYSFS_PATH_MAX];
 	int ret = 0;
 
 	/* get sysfs mount point */
@@ -384,15 +365,8 @@ int print_sysfs_buses(void)
 	}
 
 	fprintf(stdout, "Supported sysfs buses:\n");
-	current = busdir->subdirs;
-	while (current != NULL) {
-		if ((sysfs_get_name_from_path(current->path, busname,
-		    SYSFS_NAME_LEN)) != 0) {
-			sysfs_close_directory(busdir);
-			return 1;
-		}
-		fprintf(stdout, "\t%s\n", busname);
-		current = current->next;
+	dlist_for_each_data(busdir->subdirs, current, struct sysfs_directory) {
+		fprintf(stdout, "\t%s\n", current->name);
 	}
 	sysfs_close_directory(busdir);
 	return ret;
@@ -401,7 +375,7 @@ int print_sysfs_buses(void)
 /* MAIN */
 int main(int argc, char *argv[])
 {
-	char *bus_to_print = NULL;
+	unsigned char *bus_to_print = NULL;
 	int retval = 0;
 	int opt;
 	extern int optind;
diff --git a/cmd/systool.c b/cmd/systool.c
index 6b9f41d..1f22373 100644
--- a/cmd/systool.c
+++ b/cmd/systool.c
@@ -34,8 +34,8 @@
 
 /* Command Options */
 static int show_options = 0;		/* bitmask of show options */
-static char *attribute_to_show = NULL;	/* show value for this attribute */
-static char *device_to_show = NULL;	/* show only this bus device */
+static unsigned char *attribute_to_show = NULL;	/* show value for this attribute */
+static unsigned char *device_to_show = NULL;	/* show only this bus device */
 
 #define SHOW_ATTRIBUTES		0x01	/* show attributes command option */
 #define SHOW_ATTRIBUTE_VALUE	0x02	/* show an attribute value option */
@@ -45,13 +45,13 @@ static char *device_to_show = NULL;	/* show only this bus device */
                                                                                 
 #define SHOW_ALL		0xff
 
-static char cmd_options[] = "aA:b:c:dDhr:v";
+static unsigned char cmd_options[] = "aA:b:c:dDhr:v";
 
 /*
  * binary_files - defines existing sysfs binary files. These files will be
  * printed in hex.
  */
-static char *binary_files[] = {
+static unsigned char *binary_files[] = {
 	"config",
 	"data"
 };
@@ -93,9 +93,9 @@ void indent(int level)
  * remove_end_newline: removes newline on the end of an attribute value
  * @value: string to remove newline from
  */
-void remove_end_newline(char *value)
+void remove_end_newline(unsigned char *value)
 {
-	char *p = value + (strlen(value) - 1);
+	unsigned char *p = value + (strlen(value) - 1);
 
 	if (p != NULL && *p == '\n')
 		*p = '\0';
@@ -111,26 +111,21 @@ void show_device_children(struct sysfs_directory *sdir, int level)
 		indent(level);
 		fprintf(stdout, "Children:\n");
 		if (sdir->subdirs != NULL) {
-			char dirname[SYSFS_NAME_LEN];
-			struct sysfs_directory *cur = sdir->subdirs;
-
-			while (cur != NULL) {
+			struct sysfs_directory *cur;
+		
+			dlist_for_each_data(sdir->subdirs, cur, 
+					struct sysfs_directory) {
 				indent(level+4);
-				if ((sysfs_get_name_from_path(cur->path, 
-				    dirname, SYSFS_NAME_LEN)) == 0)
-					fprintf(stdout, "%s\n", dirname);
-				else
-					fprintf(stdout, "%s\n", cur->path);
-				cur = cur->next;
+				fprintf(stdout, "%s\n", cur->name);
 			}
 		}
 		if (sdir->links != NULL) {
-			struct sysfs_link *curl = sdir->links;
-
-			while (curl != 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);
-				curl = curl->next;
 			}
 		}
 	}
@@ -143,18 +138,13 @@ void show_device_children(struct sysfs_directory *sdir, int level)
  */
 int isbinaryvalue(struct sysfs_attribute *attr)
 {
-	char attrname[SYSFS_NAME_LEN];
 	int i;
 
 	if (attr == NULL || attr->value == NULL) 
 		return 0;
 
-	if ((sysfs_get_name_from_path(attr->path, attrname, SYSFS_NAME_LEN))
-	    != 0)
-		return 0;
-
 	for (i = 0; i < binfiles; i++) 
-		if ((strcmp(attrname, binary_files[i])) == 0)
+		if ((strcmp(attr->name, binary_files[i])) == 0)
 			return 1;
 
 	return 0;
@@ -200,27 +190,21 @@ void show_attribute_value(struct sysfs_attribute *attr, int level)
  */
 void show_attribute(struct sysfs_attribute *attr, int level)
 {
-	char attrname[SYSFS_NAME_LEN];
-
 	if (attr == NULL) 
 		return;
 
-	if ((sysfs_get_name_from_path(attr->path, attrname, SYSFS_NAME_LEN)) 
-	    != 0)
-		return; 
-
 	if (show_options & SHOW_ALL_ATTRIB_VALUES) {
 		indent(level);
-		fprintf(stdout, "%s", attrname);
+		fprintf(stdout, "%s", attr->name);
 		show_attribute_value(attr, level);
 
 	} else if ((show_options & SHOW_ATTRIBUTES) || ((show_options 
-	    & SHOW_ATTRIBUTE_VALUE) && (strcmp(attrname, attribute_to_show) 
+	    & SHOW_ATTRIBUTE_VALUE) && (strcmp(attr->name, attribute_to_show) 
 	    == 0))) {
 		indent(level);
-		fprintf (stdout, "%s", attrname);
+		fprintf (stdout, "%s", attr->name);
 		if (show_options & SHOW_ATTRIBUTE_VALUE && attr->value 
-		    != NULL && (strcmp(attrname, attribute_to_show)) == 0) 
+		    != NULL && (strcmp(attr->name, attribute_to_show)) == 0) 
 			show_attribute_value(attr, level);
 
 		else 
@@ -235,13 +219,13 @@ void show_attribute(struct sysfs_attribute *attr, int level)
 void show_attributes(struct sysfs_directory *sdir, int level)
 {
 	if (sdir != NULL && sdir->attributes != NULL) {
-		struct sysfs_attribute *cur = sdir->attributes;
+		struct sysfs_attribute *cur = NULL;
 
 		indent(level);
 		fprintf (stdout, "Attributes:\n");
-		while (cur != NULL) {
+		dlist_for_each_data(sdir->attributes, cur, 
+				struct sysfs_attribute) {
 			show_attribute(cur, (level+4));
-			cur = cur->next;
 		}
 	}
 }
@@ -296,13 +280,13 @@ void show_driver_attributes(struct sysfs_driver *driver, int level)
 		struct sysfs_directory *sdir = driver->directory;
 
 		if (sdir->attributes != NULL) {
-			struct sysfs_attribute *cur = sdir->attributes;
+			struct sysfs_attribute *cur = NULL;
 
 			indent(level);
 			fprintf (stdout, "%s Attributes:\n", driver->name);
-			while (cur != NULL) {
+			dlist_for_each_data(sdir->attributes, cur,
+					struct sysfs_attribute) {
 				show_attribute(cur, (level+4));
-				cur = cur->next;
 			}
 		}
 	}
@@ -318,14 +302,14 @@ void show_driver_devices(struct sysfs_driver *driver, int level)
 		struct sysfs_directory *sdir = driver->directory;
 
 		if (sdir->links != NULL) {
-			struct sysfs_link *cur = sdir->links;
+			struct sysfs_link *cur = NULL;
 
 			indent(level);
 			fprintf (stdout, "Devices:\n");
-			while (cur != NULL) {
+			dlist_for_each_data(sdir->links, cur,
+					struct sysfs_link) {
 				indent(level+4);
 				fprintf (stdout, "%s\n", cur->name);
-				cur = cur->next;
 			}
 		}
 	}
@@ -367,10 +351,11 @@ void show_device_tree(struct sysfs_device *root, int level)
 			    root->bus_id) == 0)) {
 			show_root_device(root, level);
 		}
-		cur = root->children;
-		while (cur != NULL) {
-			show_device_tree(cur, (level+6));
-			cur = cur->next;
+		if (root->children != NULL) {
+			dlist_for_each_data(root->children, cur, 
+					struct sysfs_device) {
+				show_device_tree(cur, (level+6));
+			}
 		}
 	}
 }
@@ -380,7 +365,7 @@ void show_device_tree(struct sysfs_device *root, int level)
  * @busname: bus to print.
  * returns 0 with success or 1 with error.
  */
-int show_sysfs_bus(char *busname)
+int show_sysfs_bus(unsigned char *busname)
 {
 	struct sysfs_bus *bus = NULL;
 	struct sysfs_device *curdev = NULL;
@@ -398,22 +383,18 @@ int show_sysfs_bus(char *busname)
 
 	fprintf(stdout, "Bus: %s\n", busname);
 	if (bus->devices != NULL && (show_options & SHOW_DEVICES)) {
-		curdev = bus->devices;
 		if (device_to_show == NULL)
 			fprintf(stdout, "Devices:\n");
-		while (curdev != NULL) {
+		dlist_for_each_data(bus->devices, curdev, struct sysfs_device) {
 			if (device_to_show == NULL || (strcmp(device_to_show,
 			    curdev->bus_id) == 0))
 				show_device(curdev, 2);
-			curdev = curdev->next;
 		}
 	}
 	if (bus->drivers != NULL && (show_options & SHOW_DRIVERS)) {
-		curdrv = bus->drivers;
 		fprintf(stdout, "Drivers:\n");
-		while (curdrv != NULL) {
+		dlist_for_each_data(bus->drivers, curdrv, struct sysfs_driver) {
 			show_driver(curdrv, 2);
-			curdrv = curdrv->next;
 		}
 	}
 	sysfs_close_bus(bus);
@@ -427,7 +408,6 @@ int show_sysfs_bus(char *busname)
 void show_class_device(struct sysfs_class_device *dev, int level)
 {
 	struct sysfs_directory *cur = NULL;
-	char dirname[SYSFS_NAME_LEN];
 
 	if (dev != NULL) {
 		indent(level);
@@ -436,15 +416,11 @@ void show_class_device(struct sysfs_class_device *dev, int level)
 		    & (SHOW_ATTRIBUTES | SHOW_ATTRIBUTE_VALUE
 		    | SHOW_ALL_ATTRIB_VALUES))) {
 			show_attributes(dev->directory, (level+4));
-			cur = dev->directory->subdirs;
-			while (cur != NULL) {
-				if ((sysfs_get_name_from_path(cur->path,
-				     dirname, SYSFS_NAME_LEN)) == 0) {
-					indent(level+4);
-					fprintf(stdout, "%s\n", dirname);
-				}
+			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));
-				cur = cur->next;
 			}
 		}
 		if (dev->sysdevice != NULL && (show_options & SHOW_DEVICES))
@@ -459,7 +435,7 @@ void show_class_device(struct sysfs_class_device *dev, int level)
  * @classname: class to print.
  * returns 0 with success and 1 with error.
  */
-int show_sysfs_class(char *classname)
+int show_sysfs_class(unsigned char *classname)
 {
 	struct sysfs_class *cls = NULL;
 	struct sysfs_class_device *cur = NULL;
@@ -475,14 +451,13 @@ int show_sysfs_class(char *classname)
 	}
 	fprintf(stdout, "Class: %s\n", classname);
 	if (cls->devices != NULL) {
-		cur = cls->devices;
 		if (device_to_show == NULL)
 			fprintf(stdout, "Class Devices:\n");
-		while (cur != NULL) {
+		dlist_for_each_data(cls->devices, cur, 
+				struct sysfs_class_device) {
 			if (device_to_show == NULL || (strcmp(device_to_show,
 			    cur->name) == 0))
 				show_class_device(cur, 2);
-			cur = cur->next;
 		}
 	}
 
@@ -495,10 +470,10 @@ int show_sysfs_class(char *classname)
  * @rootname: device root to print.
  * returns 0 with success and 1 with error.
  */
-int show_sysfs_root(char *rootname)
+int show_sysfs_root(unsigned char *rootname)
 {
 	struct sysfs_device *root = NULL;
-	char path[SYSFS_PATH_MAX];
+	unsigned char path[SYSFS_PATH_MAX];
 
 	if (rootname == NULL) {
 		errno = EINVAL;
@@ -530,10 +505,9 @@ int show_sysfs_root(char *rootname)
  * @path: sysfs path where subdirs are.
  * returns 0 with success or 1 with error.
  */
-int show_subdirectories(char *path, int level)
+int show_subdirectories(unsigned char *path, int level)
 {
 	struct sysfs_directory *dir = NULL, *current = NULL;
-	char name[SYSFS_NAME_LEN];
 	int ret = 0;
 
 	dir = sysfs_open_directory(path);
@@ -547,16 +521,12 @@ int show_subdirectories(char *path, int level)
 		return 1;
 	}
 
-	current = dir->subdirs;
-	while (current != NULL) {
-		if ((sysfs_get_name_from_path(current->path, name,
-		    SYSFS_NAME_LEN)) != 0) {
-			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);
 		}
-		indent(level);
-		fprintf(stdout, "%s\n", name);
-		current = current->next;
 	}
 	sysfs_close_directory(dir);
 	return ret;
@@ -569,8 +539,8 @@ int show_subdirectories(char *path, int level)
  */
 int show_default_info(void)
 {
-	char sysfs_root[SYSFS_PATH_MAX];
-	char path_to_print[SYSFS_PATH_MAX];
+	unsigned char sysfs_root[SYSFS_PATH_MAX];
+	unsigned char path_to_print[SYSFS_PATH_MAX];
 	int retval = 0;
 
 	/* get sysfs mount point */
@@ -608,9 +578,9 @@ int show_default_info(void)
 /* MAIN */
 int main(int argc, char *argv[])
 {
-	char *show_bus = NULL;
-	char *show_class = NULL;
-	char *show_root = NULL;
+	unsigned char *show_bus = NULL;
+	unsigned char *show_class = NULL;
+	unsigned char *show_root = NULL;
 	int retval = 0;
 	int opt;
 	extern int optind;
diff --git a/configure b/configure
index 31dc60c..7f8d80e 100755
--- a/configure
+++ b/configure
@@ -3979,7 +3979,7 @@ fi
 done
 
 
-ac_config_files="$ac_config_files Makefile cmd/Makefile lib/Makefile"
+ac_config_files="$ac_config_files Makefile cmd/Makefile lib/Makefile test/Makefile"
 
 cat >confcache <<\_ACEOF
 # This file is a shell script that caches the results of configure
@@ -4472,6 +4472,7 @@ do
   "Makefile" ) CONFIG_FILES="$CONFIG_FILES Makefile" ;;
   "cmd/Makefile" ) CONFIG_FILES="$CONFIG_FILES cmd/Makefile" ;;
   "lib/Makefile" ) CONFIG_FILES="$CONFIG_FILES lib/Makefile" ;;
+  "test/Makefile" ) CONFIG_FILES="$CONFIG_FILES test/Makefile" ;;
   "depfiles" ) CONFIG_COMMANDS="$CONFIG_COMMANDS depfiles" ;;
   "config.h" ) CONFIG_HEADERS="$CONFIG_HEADERS config.h" ;;
   *) { { echo "$as_me:$LINENO: error: invalid argument: $ac_config_target" >&5
diff --git a/configure.ac b/configure.ac
index a7bce4d..83d62df 100644
--- a/configure.ac
+++ b/configure.ac
@@ -28,5 +28,6 @@ AC_CHECK_FUNCS([getmntent getpagesize isascii memset strrchr])
 
 AC_CONFIG_FILES([Makefile
                  cmd/Makefile
-                 lib/Makefile])
+                 lib/Makefile
+		 test/Makefile])
 AC_OUTPUT
diff --git a/include/dlist.h b/include/dlist.h
new file mode 100644
index 0000000..5da79f9
--- /dev/null
+++ b/include/dlist.h
@@ -0,0 +1,195 @@
+/*
+ * dlist.h
+ *
+ * Copyright (C) 2003 Eric J Bohm
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+#ifndef _DLIST_H_
+#define _DLIST_H_
+
+/* Double linked list header.
+   
+* navigate your list with DLIST_PREV and DLIST_NEXT.  These are macros
+* so function call overhead is minimized.
+
+* Supports perl style push, pop, shift, unshift list semantics.
+
+* You allocate the data and give dlist the pointer.  If your data is
+* complex set the dlist->del_func to a an appropriate delete using
+* dlist_new_with_delete.  Your delete function must match 
+(void * )(del(void *)
+*Otherwise dlist will just use free.
+
+* NOTE: The small amount of pain involved in doing that allows us to
+* avoid copy in copy out semantics.
+
+* Dlist uses an internal mark pointer to keep track of where you are
+* in the list.
+
+* insert and delete take a directional parameter. Where direction
+* corresponds to the direction in which you want the list to go.
+* true direction corresponded to progressing forward in the last
+* false to regressing in the list.
+* so a dlist_insert(yourlist,item,1) will insert it after the mark
+* so a dlist_insert(yourlist,item,0) will insert it before the mark
+* any insert will move the mark to the new node regardless of the direction.
+
+* Just use the dlist_(insert|delete)_(before|after) macros if you do not want
+* to think about it.
+
+*/
+#include <malloc.h>
+typedef struct dl_node {
+  struct dl_node *prev;
+  struct dl_node *next;
+  void *data;
+} DL_node;
+
+typedef struct dlist {
+  DL_node *marker;
+  unsigned long count;
+  size_t data_size;
+  void (*del_func)(void *);
+  DL_node headnode;
+  DL_node *head;
+} Dlist;
+
+Dlist *dlist_new(size_t datasize);
+Dlist *dlist_new_with_delete(size_t datasize,void (*del_func)(void*));
+void *_dlist_mark_move(Dlist *list,int direction);
+void *dlist_mark(Dlist *);
+void dlist_start(Dlist *);
+void dlist_end(Dlist *);
+
+void *dlist_insert(Dlist *,void *,int) ;
+
+void *dlist_insert_sorted(struct dlist *list, void *new, int (*sorter)(void *, void *));
+
+void dlist_delete(Dlist *,int);
+
+void dlist_push(Dlist *,void *);
+
+void dlist_unshift(Dlist *,void *);
+
+void *dlist_pop(Dlist *);
+
+void *dlist_shift(Dlist *);
+
+void dlist_destroy(Dlist *);
+
+void *dlist_find_custom(struct dlist *list, void *target, int (*comp)(void *, void *));
+void dlist_transform(struct dlist *list, void (*node_operation)(void *));
+
+
+/* 
+ * _dlist_remove is for internal use only
+ * _dlist_mark_move is for internal use only
+ */
+void *_dlist_remove(struct dlist *,struct dl_node *,int );
+
+#define dlist_prev(A) _dlist_mark_move((A),0)
+#define dlist_next(A) _dlist_mark_move((A),1)
+
+#define dlist_insert_before(A,B) dlist_insert((A),(B),0)
+#define dlist_insert_after(A,B) dlist_insert((A),(B),1)
+
+#define dlist_delete_before(A) dlist_delete((A),0)
+#define dlist_delete_after(A) dlist_delete((A),1)
+
+/**
+ * provide for loop header which iterates the mark from start to end
+ * list: the dlist pointer, use dlist_mark(list) to get iterator
+ */
+#define dlist_for_each(list) \
+	for(dlist_start(list),dlist_next(list); \
+		(list)->marker!=(list)->head;dlist_next(list))
+
+/**
+ * provide for loop header which iterates the mark from end to start
+ * list: the dlist pointer, use dlist_mark(list) to get iterator
+ */
+#define dlist_for_each_rev(list) \
+	for(dlist_end(list),dlist_prev(list); \
+		(list)->marker!=(list)->head;dlist_prev(list))
+
+/**
+ * provide for loop header which iterates through the list without moving mark
+ * list: the dlist_pointer
+ * iterator: dl_node pointer to iterate
+ */
+#define dlist_for_each_nomark(list,iterator) \
+	for((iterator)=(list)->head->next; (iterator)!=(list)->head; \
+		(iterator)=(iterator)->next)
+
+/**
+ * provide for loop header which iterates through the list without moving mark
+ * in reverse
+ * list: the dlist_pointer
+ * iterator: dl_node pointer to iterate
+ */
+#define dlist_for_each_nomark_rev(list,iterator) \
+	for((iterator)=(list)->head->prev; (iterator)!=(list)->head; \
+		(iterator)=(iterator)->prev)
+/**
+ * provide for loop header which iterates through the list providing a
+ * data iterator
+ * list: the dlist pointer
+ * data_iterator: the pointer of type datatype to iterate
+ * datatype:  actual type of the contents in the dl_node->data
+ */
+
+#define dlist_for_each_data(list,data_iterator,datatype) \
+	for(dlist_start(list), (data_iterator)=(datatype *) dlist_next(list); \
+	(list)->marker!=(list)->head;(data_iterator)=(datatype *) dlist_next(list))
+
+/**
+ * provide for loop header which iterates through the list providing a
+ * data iterator in reverse
+ * list: the dlist pointer
+ * data_iterator: the pointer of type datatype to iterate
+ * datatype:  actual type of the contents in the dl_node->data
+ */
+#define dlist_for_each_data_rev(list,data_iterator,datatype) \
+	for(dlist_end(list), (data_iterator)=(datatype *) dlist_prev(list); \
+	(list)->marker!=(list)->head;(data_iterator)=(datatype *) dlist_prev(list))
+
+/**
+ * provide for loop header which iterates through the list providing a
+ * data iterator without moving the mark
+ * list: the dlist pointer
+ * iterator: the dl_node pointer to iterate
+ * data_iterator: the pointer of type datatype to iterate
+ * datatype:  actual type of the contents in the dl_node->data
+ */
+
+#define dlist_for_each_data_nomark(list,iterator,data_iterator,datatype) \
+	for((iterator)=(list)->head->next, (data_iterator)=(datatype *) (iterator)->data; \
+	(iterator)!=(list)->head;(iterator)=(iterator)->next,(data_iterator)=(datatype *) (iterator))
+
+/**
+ * provide for loop header which iterates through the list providing a
+ * data iterator in reverse without moving the mark
+ * list: the dlist pointer
+ * iterator: the dl_node pointer to iterate
+ * data_iterator: the pointer of type datatype to iterate
+ * datatype:  actual type of the contents in the dl_node->data
+ */
+#define dlist_for_each_data_nomark_rev(list,iterator, data_iterator,datatype) \
+	for((iterator)=(list)->head->prev, (data_iterator)=(datatype *) (iterator)->data; \
+	(iterator)!=(list)->head;(iterator)=(iterator)->prev,(data_iterator)=(datatype *) (iterator))
+
+#endif /* _DLIST_H_ */
diff --git a/include/libsysfs.h b/include/libsysfs.h
index 93fd1a9..c8df636 100644
--- a/include/libsysfs.h
+++ b/include/libsysfs.h
@@ -24,6 +24,7 @@
 #define _LIBSYSFS_H_
 
 #include <sys/types.h>
+#include "dlist.h"
 
 /*
  * Generic #defines go here..
@@ -37,6 +38,7 @@
 #define SYSFS_DRIVERS_DIR	"/drivers"
 #define SYSFS_DRIVERS_NAME	"drivers"
 #define SYSFS_NAME_ATTRIBUTE	"name"
+#define SYSFS_UNKNOWN		"unknown"
 
 #define SYSFS_PATH_MAX		255
 #define	SYSFS_NAME_LEN		50
@@ -46,65 +48,76 @@
 #define SYSFS_METHOD_STORE	0x02	/* attr can be changed by user */
 
 struct sysfs_attribute {
-	struct sysfs_attribute *next;
-	char path[SYSFS_PATH_MAX];
-	char *value;
+	unsigned char *value;
 	unsigned short len;		/* value length */
 	unsigned short method;		/* show and store */
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char path[SYSFS_PATH_MAX];
 };
 
 struct sysfs_link {
-	struct sysfs_link *next;
-	char name[SYSFS_NAME_LEN];
-	char target[SYSFS_PATH_MAX];
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char path[SYSFS_PATH_MAX];
+	unsigned char target[SYSFS_PATH_MAX];
 };
 
 struct sysfs_directory {
-	struct sysfs_directory *next;
-	char path[SYSFS_PATH_MAX];
-	struct sysfs_directory *subdirs;
-	struct sysfs_link *links;
-	struct sysfs_attribute *attributes;
+	struct dlist *subdirs;	
+	struct dlist *links;		
+	struct dlist *attributes;
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char path[SYSFS_PATH_MAX];
 };
 
 struct sysfs_driver {
-	struct sysfs_driver *next;
-	char name[SYSFS_NAME_LEN];
-	struct sysfs_directory *directory;
-	struct sysfs_device *device;
+	struct sysfs_device *device;	
+	struct dlist *devices;
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char path[SYSFS_PATH_MAX];
+
+	/* for internal use only */
+	struct sysfs_directory *directory;	
 };
 
 struct sysfs_device {
-	struct sysfs_device *next;
-	char name[SYSFS_NAME_LEN];
-	char bus_id[SYSFS_NAME_LEN];
 	struct sysfs_driver *driver;
-	struct sysfs_directory *directory;
-	struct sysfs_device *parent;
-	struct sysfs_device *children;
+	struct sysfs_device *parent;		
+	struct dlist *children;	
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char bus_id[SYSFS_NAME_LEN];
+	unsigned char bus_name[SYSFS_NAME_LEN];
+
+	/* for internal use only */
+	struct sysfs_directory *directory;	
 };
 
 struct sysfs_bus {
-	struct sysfs_bus *next;
-	char name[SYSFS_NAME_LEN];
-	struct sysfs_directory *directory;
-	struct sysfs_driver *drivers;
-	struct sysfs_device *devices;
+	struct dlist *drivers;
+	struct dlist *devices;
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char path[SYSFS_PATH_MAX];
+
+	/* internal use only */
+	struct sysfs_directory *directory;	
 };
 
 struct sysfs_class_device {
-	struct sysfs_class_device *next;
-	char name[SYSFS_NAME_LEN];
-	struct sysfs_directory *directory;
 	struct sysfs_device *sysdevice;		/* NULL if virtual */
 	struct sysfs_driver *driver;		/* NULL if not implemented */
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char path[SYSFS_PATH_MAX];
+
+	/* for internal use only */
+	struct sysfs_directory *directory;	
 };
 
 struct sysfs_class {
-	struct sysfs_class *next;
-	char name[SYSFS_NAME_LEN];
-	struct sysfs_directory *directory;
-	struct sysfs_class_device *devices;
+	struct dlist *devices;
+	unsigned char name[SYSFS_NAME_LEN];
+	unsigned char path[SYSFS_PATH_MAX];
+
+	/* for internal use only */
+	struct sysfs_directory *directory;	
 };
 
 #ifdef __cplusplus
@@ -114,45 +127,68 @@ extern "C" {
 /*
  * Function Prototypes
  */
-extern int sysfs_get_mnt_path(char *mnt_path, size_t len);
-extern int sysfs_get_name_from_path(const char *path, char *name, size_t len);
-extern int sysfs_get_link(const char *path, char *target, size_t len);
+extern int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len);
+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);
 
 /* sysfs directory and file access */
 extern void sysfs_close_attribute(struct sysfs_attribute *sysattr);
-extern struct sysfs_attribute *sysfs_open_attribute(const char *path);
+extern struct sysfs_attribute *sysfs_open_attribute(const unsigned char *path);
 extern int sysfs_read_attribute(struct sysfs_attribute *sysattr);
-extern int sysfs_read_attribute_value(const char *attrpath, char *value, 
-								size_t vsize);
-extern char *sysfs_get_value_from_attributes(struct sysfs_attribute *attr, 
-							const char * name);
+extern int sysfs_read_attribute_value(const unsigned char *attrpath, 
+				unsigned char *value, size_t vsize);
+extern unsigned char *sysfs_get_value_from_attributes(struct dlist *attr, 
+						const unsigned char * name);
 extern void sysfs_close_directory(struct sysfs_directory *sysdir);
-extern struct sysfs_directory *sysfs_open_directory(const char *path);
+extern struct sysfs_directory *sysfs_open_directory(const unsigned char *path);
 extern int sysfs_read_directory(struct sysfs_directory *sysdir);
+extern int sysfs_read_all_subdirs(struct sysfs_directory *sysdir);
+extern struct sysfs_directory *sysfs_get_subdirectory
+			(struct sysfs_directory *dir, unsigned char *subname);
 extern void sysfs_close_link(struct sysfs_link *ln);
-extern struct sysfs_link *sysfs_open_link(const char *lnpath);
+extern struct sysfs_link *sysfs_open_link(const unsigned char *lnpath);
+extern struct sysfs_link *sysfs_get_directory_link(struct sysfs_directory *dir,
+						unsigned char *linkname);
+extern struct sysfs_link *sysfs_get_subdirectory_link
+			(struct sysfs_directory *dir, unsigned char *linkname);
+extern struct sysfs_attribute *sysfs_get_directory_attribute
+			(struct sysfs_directory *dir, unsigned char *attrname);
 
 /* sysfs driver access */
 extern void sysfs_close_driver(struct sysfs_driver *driver);
-extern struct sysfs_driver *sysfs_open_driver(const char *path);
+extern struct sysfs_driver *sysfs_open_driver(const unsigned char *path);
 
 /* generic sysfs device access */
 extern void sysfs_close_device(struct sysfs_device *dev);
 extern void sysfs_close_device_tree(struct sysfs_device *dev);
-extern struct sysfs_device *sysfs_open_device(const char *path);
-extern struct sysfs_device *sysfs_open_device_tree(const char *path);
+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 char *name);
+			(struct sysfs_device *dev, const unsigned char *name);
 
 /* generic sysfs bus access */
 extern void sysfs_close_bus(struct sysfs_bus *bus);
-extern struct sysfs_bus *sysfs_open_bus(const char *name);
+extern struct sysfs_bus *sysfs_open_bus(const unsigned char *name);
+extern struct sysfs_device *sysfs_get_bus_device(struct sysfs_bus *bus,
+						unsigned char *id);
+extern struct sysfs_driver *sysfs_get_bus_driver(struct sysfs_bus *bus,
+						unsigned char *drvname);
+extern struct dlist *sysfs_get_bus_attributes(struct sysfs_bus *bus);
+extern struct sysfs_attribute *sysfs_get_bus_attribute(struct sysfs_bus *bus,
+						unsigned char *attrname);
+extern struct sysfs_device *sysfs_open_bus_device(unsigned char *busname, 
+							unsigned char *dev_id);
+extern int sysfs_find_device_bus_name(unsigned char *dev_id, 
+					unsigned char *busname,	size_t bsize);
 
 /* generic sysfs class access */
 extern void sysfs_close_class_device(struct sysfs_class_device *dev);
-extern struct sysfs_class_device *sysfs_open_class_device(const char *path);
+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 char *name);
+extern struct sysfs_class *sysfs_open_class(const unsigned char *name);
 
 #ifdef __cplusplus
 }
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 0be483c..d343f01 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -1,5 +1,5 @@
 lib_LIBRARIES = libsysfs.a
 libsysfs_a_SOURCES = sysfs_utils.c sysfs_dir.c sysfs_bus.c sysfs_class.c \
-	sysfs_device.c sysfs_driver.c sysfs.h
+	sysfs_device.c sysfs_driver.c sysfs.h dlist.c
 INCLUDES = -I../include
 
diff --git a/lib/Makefile.in b/lib/Makefile.in
index d37639a..a2e859e 100644
--- a/lib/Makefile.in
+++ b/lib/Makefile.in
@@ -77,7 +77,7 @@ am__quote = @am__quote@
 install_sh = @install_sh@
 lib_LIBRARIES = libsysfs.a
 libsysfs_a_SOURCES = sysfs_utils.c sysfs_dir.c sysfs_bus.c sysfs_class.c \
-	sysfs_device.c sysfs_driver.c sysfs.h
+	sysfs_device.c sysfs_driver.c sysfs.h dlist.c
 
 INCLUDES = -I../include
 subdir = lib
@@ -90,7 +90,7 @@ libsysfs_a_AR = $(AR) cru
 libsysfs_a_LIBADD =
 am_libsysfs_a_OBJECTS = sysfs_utils.$(OBJEXT) sysfs_dir.$(OBJEXT) \
 	sysfs_bus.$(OBJEXT) sysfs_class.$(OBJEXT) \
-	sysfs_device.$(OBJEXT) sysfs_driver.$(OBJEXT)
+	sysfs_device.$(OBJEXT) sysfs_driver.$(OBJEXT) dlist.$(OBJEXT)
 libsysfs_a_OBJECTS = $(am_libsysfs_a_OBJECTS)
 
 DEFS = @DEFS@
@@ -100,7 +100,7 @@ LDFLAGS = @LDFLAGS@
 LIBS = @LIBS@
 depcomp = $(SHELL) $(top_srcdir)/depcomp
 am__depfiles_maybe = depfiles
-@AMDEP_TRUE@DEP_FILES = ./$(DEPDIR)/sysfs_bus.Po \
+@AMDEP_TRUE@DEP_FILES = ./$(DEPDIR)/dlist.Po ./$(DEPDIR)/sysfs_bus.Po \
 @AMDEP_TRUE@	./$(DEPDIR)/sysfs_class.Po \
 @AMDEP_TRUE@	./$(DEPDIR)/sysfs_device.Po \
 @AMDEP_TRUE@	./$(DEPDIR)/sysfs_dir.Po \
@@ -167,6 +167,7 @@ mostlyclean-compile:
 distclean-compile:
 	-rm -f *.tab.c
 
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dlist.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/sysfs_bus.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/sysfs_class.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/sysfs_device.Po@am__quote@
diff --git a/lib/dlist.c b/lib/dlist.c
new file mode 100644
index 0000000..6dfcf72
--- /dev/null
+++ b/lib/dlist.c
@@ -0,0 +1,343 @@
+/*
+ * dlist.c
+ *
+ * Copyright (C) 2003 Eric J Bohm
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 021110307 USA
+ *
+ */
+
+
+/* Double linked list implementation.
+
+ * You allocate the data and give dlist the pointer.
+ * If your data is complex set the dlist->del_func to a an appropriate
+ * delete function.  Otherwise dlist will just use free.
+
+*/
+#include "dlist.h"
+
+/*
+ * Return pointer to node at marker.
+ * else null if no nodes.
+ */
+
+inline void *dlist_mark(Dlist *list)
+{
+  if(list->marker!=NULL)
+    return(list->marker->data);
+  else
+    return(NULL);
+}
+
+/* 
+ * Set marker to start.
+ */
+
+inline void dlist_start(Dlist *list)
+{
+  list->marker=list->head;
+}
+
+/* 
+ * Set marker to end.
+ */
+
+inline void dlist_end(Dlist *list)
+{
+  list->marker=list->head;
+}
+
+/* internal use function
+ * quickie inline to consolidate the marker movement logic
+ * in one place
+ *
+ * when direction true it moves marker after 
+ * when direction false it moves marker before.
+ * return pointer to data at new marker
+ * if nowhere to move the marker in desired direction return null 
+ */
+inline void *_dlist_mark_move(Dlist *list,int direction)
+{
+  if(direction)
+    {
+      if( list->marker->next!=NULL)
+	list->marker=list->marker->next;
+      else
+	return(NULL);
+    }
+  else
+    {
+      if( list->marker->prev!=NULL)
+	list->marker=list->marker->prev;
+      else
+	return(NULL);
+    }
+  if(list->marker!=list->head)
+    return(list->marker->data);
+  else
+    return(NULL);
+}
+
+/*
+ * Create new linked list to store nodes of datasize.
+ * return null if list cannot be created.
+ */
+Dlist *dlist_new(size_t datasize)
+{
+  Dlist *list=NULL;
+  if((list=malloc(sizeof(Dlist))))
+    {
+      list->marker=NULL;
+      list->count=0L;
+      list->data_size=datasize;
+      list->del_func=free;
+      list->head=&(list->headnode);
+      list->head->prev=NULL;
+      list->head->next=NULL;
+      list->head->data=NULL;
+    }
+  return(list);
+}
+
+/*
+ * Create new linked list to store nodes of datasize set list
+ * data node delete function to the passed in del_func
+ * return null if list cannot be created.
+ */
+Dlist *dlist_new_with_delete(size_t datasize,void (*del_func)(void*))
+{
+  Dlist *list=NULL;
+  list=dlist_new(datasize);
+  if(list!=NULL)
+    list->del_func=del_func;
+  return(list);
+}
+
+
+/*
+ * remove marker node from list
+ * call data_delete function on data if registered.
+ * otherwise call free.
+ * when direction true it moves marker after 
+ * when direction false it moves marker before.
+ * free marker node
+ * return nothing.
+ */
+void dlist_delete(Dlist *list,int direction)
+{
+  if((list->marker != list->head)&&(list->marker!=NULL)) 
+    {
+      DL_node *corpse;
+      corpse=list->marker;
+      _dlist_mark_move(list,direction);
+      if(list->head->next==corpse)
+	list->head->next=corpse->next;
+      if(list->head->prev==corpse)
+	list->head->prev=corpse->prev;
+      if(corpse->prev!=NULL) //should be impossible
+	corpse->prev->next=corpse->next;
+      if(corpse->next!=NULL) //should be impossible
+	corpse->next->prev=corpse->prev;
+      list->del_func(corpse->data);
+      list->count--;
+      free(corpse);
+    }
+}
+
+/*
+ * Insert node containing data at marker.
+ * If direction true it inserts after.
+ * If direction false it inserts before.
+ * move marker to inserted node
+ * return pointer to inserted node
+ */
+void *dlist_insert(Dlist *list,void *data,int direction)
+{
+  DL_node *new_node=NULL;
+  if(list==NULL || data==NULL)
+    return(NULL);
+  if(list->marker==NULL) //in case the marker ends up unset
+    list->marker=list->head;
+  if((new_node=malloc(sizeof(DL_node))))
+    {
+      new_node->data=data;
+      new_node->prev=NULL;
+      new_node->next=NULL;
+      list->count++;
+      if(list->head->next==NULL) //no l
+	{
+	  list->head->next=list->head->prev=new_node;
+	  new_node->prev=list->head;
+	  new_node->next=list->head;
+	}
+      else if(direction)
+	{
+	  new_node->next=list->marker->next;
+	  new_node->prev=list->marker;
+	  list->marker->next->prev=new_node;
+	  list->marker->next=new_node;
+	}
+      else
+	{
+	  new_node->prev=list->marker->prev;
+	  new_node->next=list->marker;
+	  list->marker->prev->next=new_node;
+	  list->marker->prev=new_node;
+	}
+	list->marker=new_node;
+    }
+  else
+    {
+      return(NULL);
+    }
+  return(list->marker->data);
+}
+
+/* 
+ * Remove DL_node from list without deallocating data.
+ * if marker == killme .
+ *  when direction true it moves marker after 
+ *  when direction false it moves marker before.
+ * to previous if there is no next.
+ */
+void *_dlist_remove(Dlist *list,DL_node *killme,int direction)
+{
+  if(killme!=NULL)
+    {
+      void *killer_data=killme->data;
+      // take care of head and marker pointers.
+      if(list->marker==killme)
+	_dlist_mark_move(list,direction);
+      if(killme ==list->head->next)
+	list->head->next=killme->next;
+      if(killme==list->head->prev)  
+	list->head->prev=killme->prev;
+      // remove from list
+      if(killme->prev !=NULL)
+	killme->prev->next=killme->next;
+      if(killme->next !=NULL)
+	killme->next->prev=killme->prev;
+      list->count--;
+      free(killme);
+      return(killer_data);
+    }
+  else
+    return (NULL);
+}
+
+
+/*
+ * Insert node containing data after end.
+ */
+void dlist_push(Dlist *list,void *data)
+{
+  list->marker=list->head->prev;
+  dlist_insert(list,data,1);
+}
+
+/*
+ * Insert node containing data at start.
+ */
+
+void dlist_unshift(Dlist *list,void *data)
+
+{
+  list->marker=list->head->next;
+  dlist_insert(list,data,0);
+}
+
+
+/* 
+ * Remove end node from list.
+ * Return pointer to data in removed node.
+ * Null if no nodes.
+ */
+
+void *dlist_pop(Dlist *list)
+{
+  return(_dlist_remove(list,list->head->prev,0));
+}
+
+/* 
+ * Remove start node from list.
+ * Return pointer to data in removed node.
+ * Null if no nodes.
+ */
+
+void *dlist_shift(Dlist *list)
+{
+  return(_dlist_remove(list,list->head->next,1));
+}
+
+
+/* 
+ * destroy the list freeing all memory
+ */
+
+
+void dlist_destroy(Dlist *list)
+{
+  if(list !=NULL)
+    {
+      dlist_start(list);
+      dlist_next(list);
+      while (dlist_mark(list)) {
+	      dlist_delete(list,1);
+      }
+      free(list);
+    }
+}
+
+/**
+ *  Return void pointer to list_data element matching comp function criteria
+ *  else null
+ *  Does not move the marker.
+ */
+
+void *dlist_find_custom(struct dlist *list, void *target, int (*comp)(void *, void *))
+{
+	/* test the comp function on each node */
+	struct dl_node *nodepointer;
+	dlist_for_each_nomark(list,nodepointer)
+		if(comp(target,nodepointer->data))
+			return(nodepointer->data);
+	return(NULL);
+}
+
+/**
+ * Apply the node_operation function to each data node in the list
+ */
+void dlist_transform(struct dlist *list, void (*node_operation)(void *))
+{
+	struct dl_node *nodepointer;
+	dlist_for_each_nomark(list,nodepointer)
+		node_operation(nodepointer->data);
+}
+
+/**
+ * insert new into list in sorted order
+ * sorter function in form int sorter(new,ith)
+ *       must return 1 for when new should go before ith
+ *       else 0
+ * return pointer to inserted node
+ * NOTE: assumes list is already sorted
+ */
+void *dlist_insert_sorted(struct dlist *list, void *new, int (*sorter)(void *, void *))
+{
+	for(dlist_start(list),dlist_next(list); \
+		list->marker!=list->head && !sorter(new,list->marker->data);dlist_next(list));
+	return(dlist_insert_before(list,new));
+}
diff --git a/lib/sysfs_bus.c b/lib/sysfs_bus.c
index e61b5a8..908da5c 100644
--- a/lib/sysfs_bus.c
+++ b/lib/sysfs_bus.c
@@ -23,28 +23,62 @@
 #include "libsysfs.h"
 #include "sysfs.h"
 
+static void sysfs_close_dev(void *dev)
+{
+	        sysfs_close_device((struct sysfs_device *)dev);
+}
+
+static void sysfs_close_drv(void *drv)
+{
+	        sysfs_close_driver((struct sysfs_driver *)drv);
+}
+
+/*
+ * compares devices' bus ids.
+ * @a: device id looking for
+ * @b: sysfs_device comparing being compared
+ * returns 1 if a==b->bus_id or 0 not equal
+ */
+static int bus_device_id_equal(void *a, void *b)
+{
+	if (a == NULL || b == NULL)
+		return 0;
+
+	if (strcmp(((unsigned char *)a), ((struct sysfs_device *)b)->bus_id) 
+	    == 0)
+		return 1;
+	return 0;
+}
+
+/*
+ * compares drivers' names.
+ * @a: driver name looking for
+ * @b: sysfs_driver comparing being compared
+ * returns 1 if a==b->name or 0 not equal
+ */
+static int bus_driver_name_equal(void *a, void *b)
+{
+	if (a == NULL || b == NULL)
+		return 0;
+
+	if (strcmp(((unsigned char *)a), ((struct sysfs_driver *)b)->name) == 0)
+		return 1;
+	return 0;
+}
+
 /**
  * sysfs_close_bus: close single bus
  * @bus: bus structure
  */
 void sysfs_close_bus(struct sysfs_bus *bus)
 {
-	struct sysfs_device *curdev = NULL, *nextdev = NULL;
-	struct sysfs_driver *curdrv = NULL, *nextdrv = NULL;
-
 	if (bus != NULL) {
 		if (bus->directory != NULL)
 			sysfs_close_directory(bus->directory);
-		for (curdev = bus->devices; curdev != NULL;
-		     curdev = nextdev) {
-			nextdev = curdev->next;
-			sysfs_close_device(curdev);
-		}
-		for (curdrv = bus->drivers; curdrv != NULL;
-		     curdrv = nextdrv) {
-			nextdrv = curdrv->next;
-			sysfs_close_driver(curdrv);
-		}
+		if (bus->devices)
+			dlist_destroy(bus->devices);
+		if (bus->drivers)
+			dlist_destroy(bus->drivers);
 		free(bus);
 	}
 }
@@ -62,10 +96,10 @@ static struct sysfs_bus *alloc_bus(void)
  * open_bus_dir: opens up sysfs bus directory
  * returns sysfs_directory struct with success and NULL with error
  */
-static struct sysfs_directory *open_bus_dir(const char *name)
+static struct sysfs_directory *open_bus_dir(const unsigned char *name)
 {
-	struct sysfs_directory *busdir = NULL, *cur = NULL, *next = NULL;
-	char buspath[SYSFS_PATH_MAX];
+	struct sysfs_directory *busdir = NULL;
+	unsigned char buspath[SYSFS_PATH_MAX];
 
 	if (name == NULL) {
 		errno = EINVAL;
@@ -95,43 +129,12 @@ static struct sysfs_directory *open_bus_dir(const char *name)
 		return NULL;
 	}
 	/* read in devices and drivers subdirs */
-	for (cur = busdir->subdirs; cur != NULL; cur = next) {
-		next = cur->next;
-		if ((sysfs_read_directory(cur)) != 0)
-			continue;
-	}
+	sysfs_read_all_subdirs(busdir);
 
 	return busdir;
 }
 
 /**
- * add_dev_to_bus: adds a bus device to bus device list
- * @bus: bus to add the device
- * @dev: device to add
- */
-static void add_dev_to_bus(struct sysfs_bus *bus, struct sysfs_device *dev)
-{
-	if (bus != NULL && dev != NULL) {
-		dev->next = bus->devices;
-		bus->devices = dev;
-	}
-}
-
-/**
- * add_driver_to_bus: adds a bus driver to bus driver list
- * @bus: bus to add driver to
- * @driver: driver to add
- */
-static void add_driver_to_bus(struct sysfs_bus *bus, 
-				struct sysfs_driver *driver)
-{
-	if (bus != NULL && driver != NULL) {
-		driver->next = bus->drivers;
-		bus->drivers = driver;
-	}
-}
-
-/**
  * get_all_bus_devices: gets all devices for bus
  * @bus: bus to get devices for
  * returns 0 with success and -1 with failure
@@ -140,29 +143,33 @@ static int get_all_bus_devices(struct sysfs_bus *bus)
 {
 	struct sysfs_device *bdev = NULL;
 	struct sysfs_directory *cur = NULL;
-	struct sysfs_link *curl = NULL, *nextl = NULL;
-	char dirname[SYSFS_NAME_LEN];
+	struct sysfs_link *curl = NULL;
 
 	if (bus == NULL || bus->directory == NULL) {
 		errno = EINVAL;
 		return -1;
 	}
-	for (cur = bus->directory->subdirs; cur != NULL; cur = cur->next) {
-		memset(dirname, 0, SYSFS_NAME_LEN);
-		if ((sysfs_get_name_from_path(cur->path, dirname,
-		    SYSFS_NAME_LEN)) != 0)
+	if (bus->directory->subdirs == NULL)
+		return 0;
+
+	dlist_for_each_data(bus->directory->subdirs, cur, 
+			struct sysfs_directory) {
+		if (strcmp(cur->name, SYSFS_DEVICES_NAME) != 0)
 			continue;
-		if (strcmp(dirname, SYSFS_DEVICES_NAME) != 0)
+		if (cur->links == NULL)
 			continue;
-		for (curl = cur->links; curl != NULL; curl = nextl) {
-			nextl = curl->next;
+		dlist_for_each_data(cur->links, curl, struct sysfs_link) {
 			bdev = sysfs_open_device(curl->target);
 			if (bdev == NULL) {
 				dprintf("Error opening device at %s\n",
 					curl->target);
 				continue;
 			}
-			add_dev_to_bus(bus, bdev);
+                        if (bus->devices == NULL)
+				bus->devices = dlist_new_with_delete
+					(sizeof(struct sysfs_device),
+						 	sysfs_close_dev);
+			dlist_unshift(bus->devices, bdev);
 		}
 	}
 			
@@ -177,31 +184,35 @@ static int get_all_bus_devices(struct sysfs_bus *bus)
 static int get_all_bus_drivers(struct sysfs_bus *bus)
 {
 	struct sysfs_driver *driver = NULL;
-	struct sysfs_directory *cur = NULL, *next = NULL;
-	struct sysfs_directory *cursub = NULL, *nextsub = NULL;
-	char dirname[SYSFS_NAME_LEN];
+	struct sysfs_directory *cur = NULL;
+	struct sysfs_directory *cursub = NULL;
 
 	if (bus == NULL || bus->directory == NULL) {
 		errno = EINVAL;
 		return -1;
 	}
-	for (cur = bus->directory->subdirs; cur != NULL; cur = next) {
-		next = cur->next;
-		memset(dirname, 0, SYSFS_NAME_LEN);
-		if ((sysfs_get_name_from_path(cur->path, dirname,
-		    SYSFS_NAME_LEN)) != 0)
+	if (bus->directory->subdirs == NULL)
+		return 0;
+
+	dlist_for_each_data(bus->directory->subdirs, cur,
+			struct sysfs_directory) {
+		if (strcmp(cur->name, SYSFS_DRIVERS_NAME) != 0)
 			continue;
-		if (strcmp(dirname, SYSFS_DRIVERS_NAME) != 0)
+		if (cur->subdirs == NULL)
 			continue;
-		for (cursub = cur->subdirs; cursub != NULL; cursub = nextsub) {
-			nextsub = cursub->next;
+		dlist_for_each_data(cur->subdirs, cursub,
+				struct sysfs_directory) {
 			driver = sysfs_open_driver(cursub->path);
 			if (driver == NULL) {
 				dprintf("Error opening driver at %s\n",
 					cursub->path);
 				continue;
 			}
-			add_driver_to_bus(bus, driver);
+                        if (bus->drivers == NULL)
+				bus->drivers = dlist_new_with_delete
+					(sizeof(struct sysfs_driver),
+					 		sysfs_close_drv);
+			dlist_unshift(bus->drivers, driver);
 		}
 	}
 	
@@ -214,20 +225,22 @@ static int get_all_bus_drivers(struct sysfs_bus *bus)
  * @busid: busid of device to match
  * returns 1 if found and 0 if not found
  */
-static int match_bus_device_to_driver(struct sysfs_driver *driver, char *busid)
+static int match_bus_device_to_driver(struct sysfs_driver *driver, 
+							unsigned char *busid)
 {
-	struct sysfs_link *cur = NULL, *next = NULL;
+	struct sysfs_link *cur = NULL;
 	int found = 0;
 
 	if (driver == NULL || driver->directory == NULL || busid == NULL) {
 		errno = EINVAL;
 		return found;
 	}
-	for (cur = driver->directory->links; cur != NULL && found == 0;
-	     cur = next) {
-		next = cur->next;
-		if ((strcmp(cur->name, busid)) == 0)
-			found++;
+	if (driver->directory->links != NULL) {
+		dlist_for_each_data(driver->directory->links, cur,
+				struct sysfs_link) {
+			if ((strcmp(cur->name, busid)) == 0)
+				found++;
+		}
 	}
 	return found;
 }
@@ -238,17 +251,15 @@ static int match_bus_device_to_driver(struct sysfs_driver *driver, char *busid)
  */
 static void link_bus_devices_to_drivers(struct sysfs_bus *bus)
 {
-	struct sysfs_device *dev = NULL, *nextdev = NULL;
-	struct sysfs_driver *drv = NULL, *nextdrv = NULL;
+	struct sysfs_device *dev = NULL;
+	struct sysfs_driver *drv = NULL;
 	
 	if (bus != NULL && bus->devices != NULL && bus->drivers != NULL) {
-		for (dev = bus->devices; dev != NULL; dev = nextdev) {
-			nextdev = dev->next;
-
-			for (drv = bus->drivers; drv != NULL; drv = nextdrv) {
-				nextdrv = drv->next;
+		dlist_for_each_data(bus->devices, dev, struct sysfs_device) {
+			dlist_for_each_data(bus->drivers, drv,
+					struct sysfs_driver) {
 				if ((match_bus_device_to_driver(drv, 
-				    dev->bus_id)) != 0) {
+						dev->bus_id)) != 0) {
 					dev->driver = drv;
 					drv->device = dev;
 				}
@@ -261,7 +272,7 @@ static void link_bus_devices_to_drivers(struct sysfs_bus *bus)
  * sysfs_open_bus: opens specific bus and all its devices on system
  * returns sysfs_bus structure with success or NULL with error.
  */
-struct sysfs_bus *sysfs_open_bus(const char *name)
+struct sysfs_bus *sysfs_open_bus(const unsigned char *name)
 {
 	struct sysfs_bus *bus = NULL;
 	struct sysfs_directory *busdir = NULL;
@@ -284,6 +295,7 @@ struct sysfs_bus *sysfs_open_bus(const char *name)
 		sysfs_close_bus(bus);
 		return NULL;
 	}
+	strcpy(bus->path, busdir->path);
 	bus->directory = busdir;
 	if ((get_all_bus_devices(bus)) != 0) {
 		dprintf("Error reading %s bus devices\n", name);
@@ -299,3 +311,172 @@ struct sysfs_bus *sysfs_open_bus(const char *name)
 
 	return bus;
 }
+
+/**
+ * sysfs_get_bus_device: Get specific device on bus using device's id
+ * @bus: bus to find device on
+ * @id: bus_id for device
+ * returns struct sysfs_device reference or NULL if not found.
+ */
+struct sysfs_device *sysfs_get_bus_device(struct sysfs_bus *bus, 
+							unsigned char *id)
+{
+	if (bus == NULL || id == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	return (struct sysfs_device *)dlist_find_custom(bus->devices, id,
+		bus_device_id_equal);
+}
+
+/**
+ * sysfs_get_bus_driver: Get specific driver on bus using driver name
+ * @bus: bus to find driver on
+ * @drvname: name of driver
+ * returns struct sysfs_driver reference or NULL if not found.
+ */
+struct sysfs_driver *sysfs_get_bus_driver(struct sysfs_bus *bus, 
+							unsigned char *drvname)
+{
+	if (bus == NULL || drvname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	return (struct sysfs_driver *)dlist_find_custom(bus->drivers, drvname,
+		bus_driver_name_equal);
+}
+
+/**
+ * sysfs_get_bus_attributes: returns bus' dlist of attributes
+ * @bus: bus to get attributes for.
+ * returns dlist of attributes or NULL if there aren't any.
+ */
+struct dlist *sysfs_get_bus_attributes(struct sysfs_bus *bus)
+{
+	if (bus == NULL || bus->directory == NULL)
+		return NULL;
+	return bus->directory->attributes;
+}
+
+/**
+ * sysfs_get_bus_attribute: gets a specific bus attribute, if buses had
+ * 	attributes.
+ * @bus: bus to retrieve attribute from
+ * @attrname: attribute name to retrieve
+ * returns reference to sysfs_attribute if found or NULL if not found
+ */
+struct sysfs_attribute *sysfs_get_bus_attribute(struct sysfs_bus *bus,
+						unsigned char *attrname)
+{
+	if (bus == NULL || bus->directory == NULL || attrname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+	return sysfs_get_directory_attribute(bus->directory, attrname);
+}
+
+/**
+ * sysfs_open_bus_device: locates a device on a bus and returns it. Device
+ * 	must be closed using sysfs_close_device.
+ * @busname: Name of bus to search
+ * @dev_id: Id of device on bus.
+ * returns sysfs_device if found or NULL if not.
+ */
+struct sysfs_device *sysfs_open_bus_device(unsigned char *busname, 
+							unsigned char *dev_id)
+{
+	struct sysfs_bus *bus = NULL;
+	struct sysfs_device *dev = NULL, *rdev = NULL;
+
+	if (busname == NULL || dev_id == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	bus = sysfs_open_bus(busname);
+	if (bus == NULL) {
+		dprintf("Error opening bus %s\n", busname);
+		return NULL;
+	}
+
+	dev = sysfs_get_bus_device(bus, dev_id);
+	if (dev == NULL) {
+		dprintf("Error getting device %s on bus %s\n", dev_id,
+			busname);
+		sysfs_close_bus(bus);
+		return NULL;
+	}
+	rdev = sysfs_open_device(dev->directory->path);
+	if (rdev == NULL) {
+		dprintf("Error getting device %s on bus %s\n", dev_id,
+			busname);
+		sysfs_close_bus(bus);
+		return NULL;
+	}
+	sysfs_close_bus(bus);
+
+	return rdev;
+}
+
+/**
+ * sysfs_find_device_bus: locates the bus a device is on.
+ * @dev_id: device id.
+ * @busname: buffer to copy name to
+ * @bsize: buffer size
+ * returns 0 with success or -1 with error
+ */
+int sysfs_find_device_bus_name(unsigned char *dev_id, unsigned char *busname, 
+								size_t bsize)
+{
+	struct sysfs_directory *busdir = NULL, *cur = NULL, *devdir = NULL;
+	struct sysfs_link *ln = NULL;
+	unsigned char path[SYSFS_PATH_MAX];
+	unsigned char devpath[SYSFS_PATH_MAX];
+
+	if (dev_id == NULL || busname == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	if (sysfs_get_mnt_path(path, SYSFS_PATH_MAX) != 0) {
+		dprintf ("Error finding sysfs root\n");
+		return -1;
+	}
+	strcat(path, SYSFS_BUS_DIR);
+	busdir = sysfs_open_directory(path);
+	if (busdir == NULL) {
+		dprintf ("Error retrieving bus directory %s\n", path);
+		return -1;
+	}
+	if (sysfs_read_directory(busdir) != 0) {
+		dprintf ("Error reading directory %s\n", path);
+		sysfs_close_directory(busdir);
+		return -1;
+	}
+	if (busdir->subdirs != NULL) {
+		dlist_for_each_data(busdir->subdirs, cur, 
+				struct sysfs_directory) {
+			memset(devpath, 0, SYSFS_PATH_MAX);
+			strcpy(devpath, cur->path);
+			strcat(devpath, SYSFS_DEVICES_DIR);
+			devdir = sysfs_open_directory(devpath);
+			if (devdir == NULL)
+				continue;
+			if (sysfs_read_directory(devdir) != 0) {
+				sysfs_close_directory(devdir);
+				continue;
+			}
+			ln = sysfs_get_subdirectory_link(devdir, dev_id);
+			if (ln != NULL) {
+				strcpy(busname, cur->name);
+				sysfs_close_directory(devdir);
+				return 0;
+			}
+			sysfs_close_directory(devdir);
+		}
+	}
+	strcpy(busname, SYSFS_UNKNOWN);
+	sysfs_close_directory(busdir);
+	return 0;
+}
diff --git a/lib/sysfs_class.c b/lib/sysfs_class.c
index 704fe44..211d41f 100644
--- a/lib/sysfs_class.c
+++ b/lib/sysfs_class.c
@@ -23,6 +23,11 @@
 #include "libsysfs.h"
 #include "sysfs.h"
 
+void sysfs_close_cls_dev(void *dev)
+{
+	sysfs_close_class_device((struct sysfs_class_device *)dev);
+}
+
 /**
  * sysfs_close_class_device: closes a single class device.
  * @dev: class device to close.
@@ -46,15 +51,11 @@ void sysfs_close_class_device(struct sysfs_class_device *dev)
  */
 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->devices != NULL) 
+			dlist_destroy(cls->devices);
 		free(cls);
 	}
 }
@@ -82,10 +83,10 @@ static struct sysfs_class *alloc_class(void)
  * open_class_dir: opens up sysfs class directory
  * returns sysfs_directory struct with success and NULL with error
  */
-static struct sysfs_directory *open_class_dir(const char *name)
+static struct sysfs_directory *open_class_dir(const unsigned char *name)
 {
 	struct sysfs_directory *classdir = NULL;
-	char classpath[SYSFS_PATH_MAX];
+	unsigned char classpath[SYSFS_PATH_MAX];
 
 	if (name == NULL) {
 		errno = EINVAL;
@@ -121,10 +122,10 @@ static struct sysfs_directory *open_class_dir(const char *name)
  * @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 char *path)
+struct sysfs_class_device *sysfs_open_class_device(const unsigned char *path)
 {
 	struct sysfs_class_device *cdev = NULL;
-	struct sysfs_directory *dir = NULL, *cur = NULL;
+	struct sysfs_directory *dir = NULL;
 	struct sysfs_link *curl = NULL;
 	struct sysfs_device *sdev = NULL;
 	struct sysfs_driver *drv = NULL;
@@ -157,51 +158,36 @@ struct sysfs_class_device *sysfs_open_class_device(const char *path)
 		sysfs_close_class_device(cdev);
 		return NULL;
 	}
+	sysfs_read_all_subdirs(dir);
 	cdev->directory = dir;
+	strcpy(cdev->path, dir->path);
 
-	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);
-			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);
-			if (drv != NULL) {
-				cdev->driver = drv;
-				if (cdev->sysdevice != NULL) 
-					drv->device = cdev->sysdevice;
+	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) 
+						sdev->driver = cdev->driver;
+				}
+			} 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) 
+						drv->device = cdev->sysdevice;
+				}
 			}
 		}
-		curl = curl->next;
 	}
 	return cdev;
 }
 
 /**
- * add_dev_to_class: adds a class device to class list
- * @class: class to add the device
- * @dev: device to add
- */
-static void add_dev_to_class(struct sysfs_class *cls, 
-					struct sysfs_class_device *dev)
-{
-	if (cls != NULL && dev != NULL) {
-		dev->next = cls->devices;
-		cls->devices = dev;
-	}
-}
-
-/**
  * get_all_class_devices: gets all devices for class
  * @class: class to get devices for
  * returns 0 with success and -1 with failure
@@ -209,22 +195,27 @@ static void add_dev_to_class(struct sysfs_class *cls,
 static int get_all_class_devices(struct sysfs_class *cls)
 {
 	struct sysfs_class_device *dev = NULL;
-	struct sysfs_directory *cur = NULL, *next = NULL;
+	struct sysfs_directory *cur = NULL;
 
 	if (cls == NULL || cls->directory == NULL) {
 		errno = EINVAL;
 		return -1;
 	}
-	for (cur = cls->directory->subdirs; cur != NULL; cur = next) {
-		next = cur->next;
+	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;
 		}
-		add_dev_to_class(cls, dev);
+		if (cls->devices == NULL)
+			cls->devices = dlist_new_with_delete
+					(sizeof(struct sysfs_class_device),
+					 		sysfs_close_cls_dev);
+		dlist_unshift(cls->devices, dev);
 	}
-			
 	return 0;
 }
 
@@ -232,7 +223,7 @@ static int get_all_class_devices(struct sysfs_class *cls)
  * sysfs_open_class: opens specific class and all its devices on system
  * returns sysfs_class structure with success or NULL with error.
  */
-struct sysfs_class *sysfs_open_class(const char *name)
+struct sysfs_class *sysfs_open_class(const unsigned char *name)
 {
 	struct sysfs_class *cls = NULL;
 	struct sysfs_directory *classdir = NULL;
@@ -256,6 +247,7 @@ struct sysfs_class *sysfs_open_class(const char *name)
 		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);
diff --git a/lib/sysfs_device.c b/lib/sysfs_device.c
index 4756c05..abdbd69 100644
--- a/lib/sysfs_device.c
+++ b/lib/sysfs_device.c
@@ -24,17 +24,24 @@
 #include "sysfs.h"
 
 /**
+ * sysfs_del_device: routine for dlist integration
+ */
+static void sysfs_del_device(void *dev)
+{
+	sysfs_close_device((struct sysfs_device *)dev);
+}
+
+/**
  * sysfs_close_device: closes and cleans up a device
  * @dev = device to clean up
  */
 void sysfs_close_device(struct sysfs_device *dev)
 {
 	if (dev != NULL) {
-		dev->next = NULL;
-		dev->driver = NULL;
 		if (dev->directory != NULL)
 			sysfs_close_directory(dev->directory);
-		dev->children = NULL;
+		if (dev->children != NULL && dev->children->count == 0)
+			dlist_destroy(dev->children);
 		free(dev);
 	}
 }
@@ -55,16 +62,18 @@ static struct sysfs_device *alloc_device(void)
  * returns sysfs_attribute reference with success or NULL with error.
  */
 struct sysfs_attribute *sysfs_get_device_attr(struct sysfs_device *dev,
-						const char *name)
+						const unsigned char *name)
 {
 	struct sysfs_attribute *cur = NULL;
-	char attrname[SYSFS_NAME_LEN];
+	unsigned char attrname[SYSFS_NAME_LEN];
 
-	if (dev == NULL || dev->directory == NULL || name == NULL) {
+	if (dev == NULL || dev->directory == NULL 
+	    || dev->directory->attributes == NULL || name == NULL) {
 		errno = EINVAL;
 		return NULL;
 	}
-	for (cur = dev->directory->attributes; cur != NULL; cur = cur->next) {
+	dlist_for_each_data(dev->directory->attributes, cur,
+			struct sysfs_attribute) {
 		if ((sysfs_get_name_from_path(cur->path, attrname, 
 		    SYSFS_NAME_LEN)) != 0) 
 			continue;
@@ -82,11 +91,11 @@ struct sysfs_attribute *sysfs_get_device_attr(struct sysfs_device *dev,
  * @path: path to device, this is the /sys/devices/ path
  * returns sysfs_device structure with success or NULL with error
  */
-struct sysfs_device *sysfs_open_device(const char *path)
+struct sysfs_device *sysfs_open_device(const unsigned char *path)
 {
 	struct sysfs_device *dev = NULL;
 	struct sysfs_directory *sdir = NULL;
-	char *p = NULL;
+	unsigned char *p = NULL;
 
 	if (path == NULL) {
 		errno = EINVAL;
@@ -111,7 +120,9 @@ struct sysfs_device *sysfs_open_device(const char *path)
 		return NULL;
 	}
 	dev->directory = sdir;
-	sysfs_get_name_from_path(sdir->path, dev->bus_id, SYSFS_NAME_LEN);
+	strcpy(dev->bus_id, sdir->name);
+	sysfs_find_device_bus_name(dev->bus_id, dev->bus_name, SYSFS_NAME_LEN);
+
 	/* get device name */
 	p = sysfs_get_value_from_attributes(sdir->attributes,	
 							SYSFS_NAME_ATTRIBUTE);
@@ -134,11 +145,10 @@ void sysfs_close_device_tree(struct sysfs_device *devroot)
 {
 	if (devroot != NULL) {
 		if (devroot->children != NULL) {
-			struct sysfs_device *child = NULL, *next = NULL;
-	
-			for (child = devroot->children; child != NULL;
-			     child = next) {
-				next = child->next;
+			struct sysfs_device *child = NULL;
+
+			dlist_for_each_data(devroot->children, child,
+					struct sysfs_device) {
 				sysfs_close_device_tree(child);
 			}
 		}
@@ -147,28 +157,13 @@ void sysfs_close_device_tree(struct sysfs_device *devroot)
 }
 
 /**
- * add_device_child_to_parent: adds child device to parent
- * @parent: parent device.
- * @child: child device to add.
- */
-static void add_device_child_to_parent(struct sysfs_device *parent,
-					struct sysfs_device *child)
-{
-	if (parent != NULL && child != NULL) {
-		child->next = parent->children;
-		parent->children = child;
-		child->parent = parent;
-	}
-}
-
-/**
  * sysfs_open_device_tree: opens root device and all of its children,
  *	creating a tree of devices. Only opens children.
  * @path: sysfs path to devices
  * returns struct sysfs_device and its children with success or NULL with
  *	error.
  */
-struct sysfs_device *sysfs_open_device_tree(const char *path)
+struct sysfs_device *sysfs_open_device_tree(const unsigned char *path)
 {
 	struct sysfs_device *rootdev = NULL, *new = NULL;
 	struct sysfs_directory *cur = NULL;
@@ -182,17 +177,22 @@ struct sysfs_device *sysfs_open_device_tree(const char *path)
 		dprintf("Error opening root device at %s\n", path);
 		return NULL;
 	}
-	cur = rootdev->directory->subdirs;
-	while (cur != NULL) {
-		new = sysfs_open_device_tree(cur->path);
-		if (new == NULL) {
-			dprintf("Error opening device tree at %s\n",
-				cur->path);
-			sysfs_close_device_tree(rootdev);
-			return NULL;
+	if (rootdev->directory->subdirs != NULL) {
+		dlist_for_each_data(rootdev->directory->subdirs, cur,
+				struct sysfs_directory) {
+			new = sysfs_open_device_tree(cur->path);
+			if (new == NULL) {
+				dprintf("Error opening device tree at %s\n",
+					cur->path);
+				sysfs_close_device_tree(rootdev);
+				return NULL;
+			}
+			if (rootdev->children == NULL)
+				rootdev->children = dlist_new_with_delete
+					(sizeof(struct sysfs_device),
+					sysfs_del_device);
+			dlist_unshift(rootdev->children, new);
 		}
-		add_device_child_to_parent(rootdev, new);	
-		cur = cur->next;
 	}
 
 	return rootdev;
diff --git a/lib/sysfs_dir.c b/lib/sysfs_dir.c
index b089d81..1b365d7 100644
--- a/lib/sysfs_dir.c
+++ b/lib/sysfs_dir.c
@@ -24,6 +24,81 @@
 #include "sysfs.h"
 
 /**
+ * sysfs_del_attribute: routine for dlist integration
+ */
+static void sysfs_del_attribute(void *attr)
+{
+	        sysfs_close_attribute((struct sysfs_attribute *)attr);
+}
+
+/**
+ * sysfs_del_link: routine for dlist integration
+ */
+static void sysfs_del_link(void *ln)
+{
+	        sysfs_close_link((struct sysfs_link *)ln);
+}
+
+/**
+ * sysfs_del_dir: routine for dlist integration
+ */
+static void sysfs_del_directory(void *dir)
+{
+	        sysfs_close_directory((struct sysfs_directory *)dir);
+}
+
+/**
+ * dir_attribute_name_equal: compares dir attributes by name
+ * @a: attribute name for comparison
+ * @b: sysfs_attribute to be compared.
+ * returns 1 if a==b->name or 0 if not equal
+ */
+static int dir_attribute_name_equal(void *a, void *b)
+{
+	if (a == NULL || b == NULL)
+		return 0;
+
+	if (strcmp(((unsigned char *)a), ((struct sysfs_attribute *)b)->name) 
+	    == 0)
+		return 1;
+	return 0;
+}
+
+/**
+ * dir_link_name_equal: compares dir links by name
+ * @a: link name for comparison
+ * @b: sysfs_link to be compared.
+ * returns 1 if a==b->name or 0 if not equal
+ */
+static int dir_link_name_equal(void *a, void *b)
+{
+	if (a == NULL || b == NULL)
+		return 0;
+
+	if (strcmp(((unsigned char *)a), ((struct sysfs_link *)b)->name) 
+	    == 0)
+		return 1;
+	return 0;
+}
+
+/**
+ * dir_subdir_name_equal: compares subdirs by name
+ * @a: name of subdirectory to compare
+ * @b: sysfs_directory subdirectory to be compared
+ * returns 1 if a==b->name or 0 if not equal
+ */
+static int dir_subdir_name_equal(void *a, void *b)
+{
+	if (a == NULL || b == NULL)
+		return 0;
+
+	if (strcmp(((unsigned char *)a), ((struct sysfs_directory *)b)->name)
+	    == 0)
+		return 1;
+	return 0;
+}
+
+/**
  * sysfs_close_attribute: closes and cleans up attribute
  * @sysattr: attribute to close.
  */
@@ -51,7 +126,7 @@ static struct sysfs_attribute *alloc_attribute(void)
  * @path: path to attribute.
  * returns sysfs_attribute struct with success and NULL with error.
  */
-struct sysfs_attribute *sysfs_open_attribute(const char *path)
+struct sysfs_attribute *sysfs_open_attribute(const unsigned char *path)
 {
 	struct sysfs_attribute *sysattr = NULL;
 	struct stat fileinfo;
@@ -65,6 +140,13 @@ struct sysfs_attribute *sysfs_open_attribute(const char *path)
 		dprintf("Error allocating attribute at %s\n", path);
 		return NULL;
 	}
+	if (sysfs_get_name_from_path(path, sysattr->name, SYSFS_NAME_LEN) 
+	    != 0) {
+		dprintf("Error retrieving attribute name from path: %s\n", 
+			path);
+		sysfs_close_attribute(sysattr);
+		return NULL;
+	}
 	strncpy(sysattr->path, path, sizeof(sysattr->path));
 	if ((stat(sysattr->path, &fileinfo)) != 0) {
 		perror("stat");
@@ -86,8 +168,8 @@ struct sysfs_attribute *sysfs_open_attribute(const char *path)
  */
 int sysfs_read_attribute(struct sysfs_attribute *sysattr)
 {
-	char *fbuf = NULL;
-	char *vbuf = NULL;
+	unsigned char *fbuf = NULL;
+	unsigned char *vbuf = NULL;
 	size_t length = 0;
 	int pgsize = 0;
 	int fd;
@@ -102,7 +184,7 @@ int sysfs_read_attribute(struct sysfs_attribute *sysattr)
 		return -1;
 	}
 	pgsize = getpagesize();
-	fbuf = (char *)calloc(1, pgsize+1);
+	fbuf = (unsigned char *)calloc(1, pgsize+1);
 	if (fbuf == NULL) {
 		perror("calloc");
 		return -1;
@@ -121,7 +203,7 @@ int sysfs_read_attribute(struct sysfs_attribute *sysattr)
 	}
 	sysattr->len = length;
 	close(fd);
-	vbuf = (char *)realloc(fbuf, length+1);
+	vbuf = (unsigned char *)realloc(fbuf, length+1);
 	if (vbuf == NULL) {
 		perror("realloc");
 		free(fbuf);
@@ -141,7 +223,8 @@ int sysfs_read_attribute(struct sysfs_attribute *sysattr)
  * @vsize: size of value buffer
  * returns 0 with success and -1 with error.
  */
-int sysfs_read_attribute_value(const char *attrpath, char *value, size_t vsize)
+int sysfs_read_attribute_value(const unsigned char *attrpath, 
+					unsigned char *value, size_t vsize)
 {
 	struct sysfs_attribute *attr = NULL;
 	size_t length = 0;
@@ -177,85 +260,32 @@ int sysfs_read_attribute_value(const char *attrpath, char *value, size_t vsize)
  * 	attribute name, return its value
  * @attr: attribute to search
  * @name: name to look for
- * returns char * value - could be NULL
+ * returns unsigned char * value - could be NULL
  */
-char *sysfs_get_value_from_attributes(struct sysfs_attribute *attr, 
-					const char *name)
+unsigned char *sysfs_get_value_from_attributes(struct dlist *attr, 
+					const unsigned char *name)
 {	
 	struct sysfs_attribute *cur = NULL;
-	char tmpname[SYSFS_NAME_LEN];
 	
 	if (attr == NULL || name == NULL) {
 		errno = EINVAL;
 		return NULL;
-	}	
-	cur = attr;
-	while (cur != NULL) {
-		memset(tmpname, 0, SYSFS_NAME_LEN);	
-		if ((sysfs_get_name_from_path(cur->path, tmpname,
-		    SYSFS_NAME_LEN)) != 0) {
-			cur = cur->next;
-			continue;
-		}
-		if (strcmp(tmpname, name) == 0)
+	}
+	dlist_for_each_data(attr, cur, struct sysfs_attribute) {
+		if (strcmp(cur->name, name) == 0)
 			return cur->value;
-		cur = cur->next;
 	}
 	return NULL;
 }
 
 /**
- * add_subdir_to_dir: adds subdirectory to directory's subdirs
- * @sysdir: directory to add subdir to
- * @subdir: subdirectory to add.
- */
-static void add_subdir_to_dir(struct sysfs_directory *sysdir, 
-		     struct sysfs_directory *subdir)
-{
-	if (sysdir != NULL && subdir != NULL) {
-		subdir->next = sysdir->subdirs;
-		sysdir->subdirs = subdir;
-	}
-}
-
-/**
- * add_attr_to_dir: adds attribute to directory's attributes
- * @sysdir: directory to add attribute to
- * @sysattr: attribute to add.
- */
-static void add_attr_to_dir(struct sysfs_directory *sysdir, 
-		     			struct sysfs_attribute *sysattr)
-{
-	if (sysdir != NULL && sysattr != NULL) {
-		sysattr->next = sysdir->attributes;
-		sysdir->attributes = sysattr;
-	}
-}
-
-/**
  * sysfs_close_link: closes and cleans up link.
  * @ln: link to close.
  */
 void sysfs_close_link(struct sysfs_link *ln)
 {
-	if (ln != NULL) {
-		ln->next = NULL;
+	if (ln != NULL) 
 		free(ln);
-	}
-}
-
-/**
- * add_link_to_dir: adds link to directory's links list.
- * @sysdir: directory to add it to.
- * @ln: link to add.
- */
-static void add_link_to_dir(struct sysfs_directory *sysdir, 
-					struct sysfs_link *ln)
-{
-	if (sysdir != NULL && ln != NULL) {
-		ln->next = sysdir->links;
-		sysdir->links = ln;
-	}
 }
 
 /**
@@ -264,35 +294,13 @@ static void add_link_to_dir(struct sysfs_directory *sysdir,
  */
 void sysfs_close_directory(struct sysfs_directory *sysdir)
 {
-	struct sysfs_directory *sdir = NULL, *dnext = NULL;
-	struct sysfs_link *dlink = NULL, *nextl = NULL;
-	struct sysfs_attribute *attr = NULL, *anext = NULL;
-
 	if (sysdir != NULL) {
-		if (sysdir->subdirs != NULL) {
-			for (sdir = sysdir->subdirs; sdir != NULL;
-			     sdir = dnext) {
-				dnext = sdir->next;
-				sysfs_close_directory(sdir);
-			}
-		}
-		if (sysdir->links != NULL) {
-			for (dlink = sysdir->links; dlink != NULL;
-			    dlink = nextl) {
-				nextl = dlink->next;
-				sysfs_close_link(dlink);
-			}
-		}
-		if (sysdir->attributes != NULL) {
-			for (attr = sysdir->attributes; attr != NULL;
-			     attr = anext) {
-				anext = attr->next;
-				/* sysfs_close_attribute(attr); */
-				if (attr->value != NULL)
-					free(attr->value);
-				free(attr);
-			}
-		}
+		if (sysdir->subdirs != NULL) 
+			dlist_destroy(sysdir->subdirs);
+		if (sysdir->links != NULL)
+			dlist_destroy(sysdir->links);
+		if (sysdir->attributes != NULL) 
+			dlist_destroy(sysdir->attributes);
 		free(sysdir);
 	}
 }
@@ -317,12 +325,35 @@ static struct sysfs_link *alloc_link(void)
 }
 
 /**
+ * sysfs_read_all_subdirs: calls sysfs_read_directory for all subdirs
+ * @sysdir: directory whose subdirs need reading.
+ * returns 0 with success and -1 with error.
+ */
+int sysfs_read_all_subdirs(struct sysfs_directory *sysdir)
+{
+	struct sysfs_directory *cursub = NULL;
+
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	if (sysdir->subdirs == NULL)
+		return 0;
+	dlist_for_each_data(sysdir->subdirs, cursub, struct sysfs_directory) {
+		if (sysfs_read_directory(cursub) != 0) 
+			dprintf ("Error reading subdirectory %s\n",
+				cursub->name);
+	}
+	return 0;
+}
+
+/**
  * sysfs_open_directory: opens a sysfs directory, creates dir struct, and
  *		returns.
  * @path: path of directory to open.
  * returns: struct sysfs_directory * with success and NULL on error.
  */
-struct sysfs_directory *sysfs_open_directory(const char *path)
+struct sysfs_directory *sysfs_open_directory(const unsigned char *path)
 {
 	struct sysfs_directory *sdir = NULL;
 
@@ -335,6 +366,11 @@ struct sysfs_directory *sysfs_open_directory(const char *path)
 		dprintf("Error allocating directory %s\n", path);
 		return NULL;
 	}
+	if (sysfs_get_name_from_path(path, sdir->name, SYSFS_NAME_LEN) != 0) {
+		dprintf("Error getting directory name from path: %s\n", path);
+		sysfs_close_directory(sdir);
+		return NULL;
+	}
 	strncpy(sdir->path, path, sizeof(sdir->path));
 
 	return sdir;
@@ -345,11 +381,11 @@ struct sysfs_directory *sysfs_open_directory(const char *path)
  * @path: path of link to open.
  * returns: struct sysfs_link * with success and NULL on error.
  */
-struct sysfs_link *sysfs_open_link(const char *linkpath)
+struct sysfs_link *sysfs_open_link(const unsigned char *linkpath)
 {
 	struct sysfs_link *ln = NULL;
 
-	if (linkpath == NULL) {
+	if (linkpath == NULL || strlen(linkpath) > SYSFS_PATH_MAX) {
 		errno = EINVAL;
 		return NULL;
 	}
@@ -359,6 +395,7 @@ struct sysfs_link *sysfs_open_link(const char *linkpath)
 		dprintf("Error allocating link %s\n", linkpath);
 		return NULL;
 	}
+	strcpy(ln->path, linkpath);
 	if ((sysfs_get_name_from_path(linkpath, ln->name, SYSFS_NAME_LEN)) != 0
 	    || (sysfs_get_link(linkpath, ln->target, SYSFS_PATH_MAX)) != 0) {
 		errno = EINVAL;
@@ -382,7 +419,7 @@ int sysfs_read_directory(struct sysfs_directory *sysdir)
 	struct sysfs_attribute *attr = NULL;
 	struct sysfs_directory *subdir = NULL;
 	struct sysfs_link *ln = NULL;
-	char file_path[SYSFS_PATH_MAX];
+	unsigned char file_path[SYSFS_PATH_MAX];
 	int retval = 0;
 
 	if (sysdir == NULL) {
@@ -423,7 +460,12 @@ int sysfs_read_directory(struct sysfs_directory *sysdir)
 					continue;
 				}
 			}
-			add_attr_to_dir(sysdir, attr);
+			                        
+			if (sysdir->attributes == NULL)
+				sysdir->attributes = dlist_new_with_delete
+					(sizeof(struct sysfs_attribute),
+					 		sysfs_del_attribute);
+			dlist_unshift(sysdir->attributes, attr);
 		} else if (S_ISDIR(astats.st_mode)) {
 			subdir = sysfs_open_directory(file_path);
 			if (subdir == NULL) {
@@ -432,7 +474,11 @@ int sysfs_read_directory(struct sysfs_directory *sysdir)
 				retval = -1;
 				break;
 			}
-			add_subdir_to_dir(sysdir, subdir);
+			if (sysdir->subdirs == NULL)
+				sysdir->subdirs = dlist_new_with_delete
+					(sizeof(struct sysfs_directory),
+							sysfs_del_directory);
+			dlist_unshift(sysdir->subdirs, subdir);
 		} else if (S_ISLNK(astats.st_mode)) {
 			ln = sysfs_open_link(file_path);
 			if (ln == NULL) {
@@ -440,9 +486,111 @@ int sysfs_read_directory(struct sysfs_directory *sysdir)
 				retval = -1;
 				break;
 			}
-			add_link_to_dir(sysdir, ln);
+			if (sysdir->links == NULL)
+				sysdir->links = dlist_new_with_delete
+						(sizeof(struct sysfs_link),
+						 		sysfs_del_link);
+			dlist_unshift(sysdir->links, ln);
 		}
 	}
 	closedir(dir);
 	return(retval);
 }
+
+/**
+ * sysfs_get_directory_attribute: retrieves attribute attrname
+ * @dir: directory to retrieve attribute from
+ * @attrname: name of attribute to look for
+ * returns sysfs_attribute if found and NULL if not found
+ */
+struct sysfs_attribute *sysfs_get_directory_attribute
+			(struct sysfs_directory *dir, unsigned char *attrname)
+{
+	if (dir == NULL || attrname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+	return (struct sysfs_attribute *)dlist_find_custom(dir->attributes,
+		attrname, dir_attribute_name_equal);
+}
+
+/**
+ * sysfs_get_directory_link: retrieves link from one directory list
+ * @dir: directory to retrieve link from
+ * @linkname: name of link to look for
+ * returns reference to sysfs_link if found and NULL if not found
+ */
+struct sysfs_link *sysfs_get_directory_link
+			(struct sysfs_directory *dir, unsigned char *linkname)
+{
+	if (dir == NULL || linkname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+	return (struct sysfs_link *)dlist_find_custom(dir->links,
+		linkname, dir_link_name_equal);
+}
+
+/**
+ * sysfs_get_subdirectory: retrieves subdirectory by name.
+ * @dir: directory to search for subdirectory.
+ * @subname: subdirectory name to get.
+ * returns reference to subdirectory or NULL if not found
+ */
+struct sysfs_directory *sysfs_get_subdirectory(struct sysfs_directory *dir,
+						unsigned char *subname)
+{
+	struct sysfs_directory *sub = NULL, *cursub = NULL;
+
+	if (dir == NULL || dir->subdirs == NULL || subname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+	sub = (struct sysfs_directory *)dlist_find_custom(dir->subdirs,
+		subname, dir_subdir_name_equal);
+	if (sub != NULL) 
+		return sub;
+
+	dlist_for_each_data(dir->subdirs, cursub, struct sysfs_directory) {
+		if (cursub->subdirs == NULL)
+			continue;
+		sub = sysfs_get_subdirectory(cursub, subname);
+		if (sub != NULL)
+			return sub;
+	}
+	return NULL;
+}
+
+/**
+ * sysfs_get_subdirectory_link: looks through all subdirs for specific link.
+ * @dir: directory and subdirectories to search for link.
+ * @linkname: link name to get.
+ * returns reference to link or NULL if not found
+ */
+struct sysfs_link *sysfs_get_subdirectory_link(struct sysfs_directory *dir,
+						unsigned char *linkname)
+{
+	struct sysfs_directory *cursub = NULL;
+	struct sysfs_link *ln = NULL;
+
+	if (dir == NULL || dir->links == NULL || linkname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	ln = sysfs_get_directory_link(dir, linkname);
+	if (ln != NULL)
+		return ln;
+
+	if (dir->subdirs == NULL)
+		return NULL;
+
+	dlist_for_each_data(dir->subdirs, cursub, struct sysfs_directory) {
+		if (cursub->subdirs == NULL)
+			continue;
+		ln = sysfs_get_subdirectory_link(cursub, linkname);
+		if (ln != NULL)
+			return ln;
+	}
+	return NULL;
+}
diff --git a/lib/sysfs_driver.c b/lib/sysfs_driver.c
index 5558c03..f890b22 100644
--- a/lib/sysfs_driver.c
+++ b/lib/sysfs_driver.c
@@ -50,11 +50,10 @@ static struct sysfs_driver *alloc_driver(void)
  * @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(const unsigned char *path)
 {
 	struct sysfs_driver *driver = NULL;
 	struct sysfs_directory *sdir = NULL;
-	char devname[SYSFS_NAME_LEN];
 
 	if (path == NULL) {
 		errno = EINVAL;
@@ -76,14 +75,9 @@ struct sysfs_driver *sysfs_open_driver(const char *path)
 		sysfs_close_directory(sdir);
 		return NULL;
 	}
-	if ((sysfs_get_name_from_path(path, devname, SYSFS_NAME_LEN)) != 0) {
-		dprintf("Error reading directory %s\n", path);
-		sysfs_close_directory(sdir);
-		free(driver);
-		return NULL;
-	}
-	strncpy(driver->name, devname, sizeof(driver->name));
+	strcpy(driver->name, sdir->name);
 	driver->directory = sdir;	
+	strcpy(driver->path, sdir->path);
 	
 	return driver;
 }
diff --git a/lib/sysfs_utils.c b/lib/sysfs_utils.c
index def955e..d4c085b 100644
--- a/lib/sysfs_utils.c
+++ b/lib/sysfs_utils.c
@@ -30,8 +30,8 @@
  * @len: size of mnt_path
  * returns 0 with success and -1 with error.
  */
-static int sysfs_get_fs_mnt_path(const char *fs_type, char *mnt_path, 
-				 size_t len)
+static int sysfs_get_fs_mnt_path(const unsigned char *fs_type, 
+				unsigned char *mnt_path, size_t len)
 {
 	FILE *mnt;
 	struct mntent *mntent;
@@ -74,7 +74,7 @@ static int sysfs_get_fs_mnt_path(const char *fs_type, char *mnt_path,
  * @len: size of mnt_path
  * returns 0 with success and -1 with error.
  */
-int sysfs_get_mnt_path(char *mnt_path, size_t len)
+int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
 {
 	int ret = -1;
 
@@ -92,9 +92,10 @@ int sysfs_get_mnt_path(char *mnt_path, size_t len)
  * @name: where to put name
  * @len: size of name
  */
-int sysfs_get_name_from_path(const char *path, char *name, size_t len)
+int sysfs_get_name_from_path(const unsigned char *path, unsigned char *name, 
+								size_t len)
 {
-	char *n = NULL;
+	unsigned char *n = NULL;
                                                                                 
 	if (path == NULL || name == NULL) {
 		errno = EINVAL;
@@ -117,11 +118,11 @@ int sysfs_get_name_from_path(const char *path, char *name, size_t len)
  * @target: where to put name
  * @len: size of name
  */
-int sysfs_get_link(const char *path, char *target, size_t len)
+int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
 {
-	char devdir[SYSFS_PATH_MAX];
-	char linkpath[SYSFS_PATH_MAX];
-	char *d = NULL;
+	unsigned char devdir[SYSFS_PATH_MAX];
+	unsigned char linkpath[SYSFS_PATH_MAX];
+	unsigned char *d = NULL;
 
 	if (path == NULL || target == NULL) {
 		errno = EINVAL;
diff --git a/test/Makefile.am b/test/Makefile.am
new file mode 100644
index 0000000..25a4881
--- /dev/null
+++ b/test/Makefile.am
@@ -0,0 +1,4 @@
+bin_PROGRAMS = dlist_test
+dlist_test_SOURCES = dlist_test.c
+INCLUDES = -I../include
+LDADD = ../lib/libsysfs.a
diff --git a/test/Makefile.in b/test/Makefile.in
new file mode 100644
index 0000000..fb046a8
--- /dev/null
+++ b/test/Makefile.in
@@ -0,0 +1,316 @@
+# Makefile.in generated by automake 1.6.3 from Makefile.am.
+# @configure_input@
+
+# Copyright 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002
+# Free Software Foundation, Inc.
+# This Makefile.in is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
+# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+# PARTICULAR PURPOSE.
+
+@SET_MAKE@
+SHELL = @SHELL@
+
+srcdir = @srcdir@
+top_srcdir = @top_srcdir@
+VPATH = @srcdir@
+prefix = @prefix@
+exec_prefix = @exec_prefix@
+
+bindir = @bindir@
+sbindir = @sbindir@
+libexecdir = @libexecdir@
+datadir = @datadir@
+sysconfdir = @sysconfdir@
+sharedstatedir = @sharedstatedir@
+localstatedir = @localstatedir@
+libdir = @libdir@
+infodir = @infodir@
+mandir = @mandir@
+includedir = @includedir@
+oldincludedir = /usr/include
+pkgdatadir = $(datadir)/@PACKAGE@
+pkglibdir = $(libdir)/@PACKAGE@
+pkgincludedir = $(includedir)/@PACKAGE@
+top_builddir = ..
+
+ACLOCAL = @ACLOCAL@
+AUTOCONF = @AUTOCONF@
+AUTOMAKE = @AUTOMAKE@
+AUTOHEADER = @AUTOHEADER@
+
+am__cd = CDPATH="$${ZSH_VERSION+.}$(PATH_SEPARATOR)" && cd
+INSTALL = @INSTALL@
+INSTALL_PROGRAM = @INSTALL_PROGRAM@
+INSTALL_DATA = @INSTALL_DATA@
+install_sh_DATA = $(install_sh) -c -m 644
+install_sh_PROGRAM = $(install_sh) -c
+install_sh_SCRIPT = $(install_sh) -c
+INSTALL_SCRIPT = @INSTALL_SCRIPT@
+INSTALL_HEADER = $(INSTALL_DATA)
+transform = @program_transform_name@
+NORMAL_INSTALL = :
+PRE_INSTALL = :
+POST_INSTALL = :
+NORMAL_UNINSTALL = :
+PRE_UNINSTALL = :
+POST_UNINSTALL = :
+
+EXEEXT = @EXEEXT@
+OBJEXT = @OBJEXT@
+PATH_SEPARATOR = @PATH_SEPARATOR@
+AMTAR = @AMTAR@
+AWK = @AWK@
+CC = @CC@
+DEPDIR = @DEPDIR@
+INSTALL_STRIP_PROGRAM = @INSTALL_STRIP_PROGRAM@
+PACKAGE = @PACKAGE@
+RANLIB = @RANLIB@
+STRIP = @STRIP@
+VERSION = @VERSION@
+am__include = @am__include@
+am__quote = @am__quote@
+install_sh = @install_sh@
+bin_PROGRAMS = dlist_test
+dlist_test_SOURCES = dlist_test.c
+INCLUDES = -I../include
+LDADD = ../lib/libsysfs.a
+subdir = test
+mkinstalldirs = $(SHELL) $(top_srcdir)/mkinstalldirs
+CONFIG_HEADER = $(top_builddir)/config.h
+CONFIG_CLEAN_FILES =
+bin_PROGRAMS = dlist_test$(EXEEXT)
+PROGRAMS = $(bin_PROGRAMS)
+
+am_dlist_test_OBJECTS = dlist_test.$(OBJEXT)
+dlist_test_OBJECTS = $(am_dlist_test_OBJECTS)
+dlist_test_LDADD = $(LDADD)
+dlist_test_DEPENDENCIES = ../lib/libsysfs.a
+dlist_test_LDFLAGS =
+
+DEFS = @DEFS@
+DEFAULT_INCLUDES =  -I. -I$(srcdir) -I$(top_builddir)
+CPPFLAGS = @CPPFLAGS@
+LDFLAGS = @LDFLAGS@
+LIBS = @LIBS@
+depcomp = $(SHELL) $(top_srcdir)/depcomp
+am__depfiles_maybe = depfiles
+@AMDEP_TRUE@DEP_FILES = ./$(DEPDIR)/dlist_test.Po
+COMPILE = $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
+	$(CPPFLAGS) $(AM_CFLAGS) $(CFLAGS)
+CCLD = $(CC)
+LINK = $(CCLD) $(AM_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) $(LDFLAGS) -o $@
+CFLAGS = @CFLAGS@
+DIST_SOURCES = $(dlist_test_SOURCES)
+DIST_COMMON = Makefile.am Makefile.in
+SOURCES = $(dlist_test_SOURCES)
+
+all: all-am
+
+.SUFFIXES:
+.SUFFIXES: .c .o .obj
+$(srcdir)/Makefile.in:  Makefile.am  $(top_srcdir)/configure.ac $(ACLOCAL_M4)
+	cd $(top_srcdir) && \
+	  $(AUTOMAKE) --gnu  test/Makefile
+Makefile:  $(srcdir)/Makefile.in  $(top_builddir)/config.status
+	cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe)
+binPROGRAMS_INSTALL = $(INSTALL_PROGRAM)
+install-binPROGRAMS: $(bin_PROGRAMS)
+	@$(NORMAL_INSTALL)
+	$(mkinstalldirs) $(DESTDIR)$(bindir)
+	@list='$(bin_PROGRAMS)'; for p in $$list; do \
+	  p1=`echo $$p|sed 's/$(EXEEXT)$$//'`; \
+	  if test -f $$p \
+	  ; then \
+	    f=`echo "$$p1" | sed 's,^.*/,,;$(transform);s/$$/$(EXEEXT)/'`; \
+	   echo " $(INSTALL_PROGRAM_ENV) $(binPROGRAMS_INSTALL) $$p $(DESTDIR)$(bindir)/$$f"; \
+	   $(INSTALL_PROGRAM_ENV) $(binPROGRAMS_INSTALL) $$p $(DESTDIR)$(bindir)/$$f; \
+	  else :; fi; \
+	done
+
+uninstall-binPROGRAMS:
+	@$(NORMAL_UNINSTALL)
+	@list='$(bin_PROGRAMS)'; for p in $$list; do \
+	  f=`echo "$$p" | sed 's,^.*/,,;s/$(EXEEXT)$$//;$(transform);s/$$/$(EXEEXT)/'`; \
+	  echo " rm -f $(DESTDIR)$(bindir)/$$f"; \
+	  rm -f $(DESTDIR)$(bindir)/$$f; \
+	done
+
+clean-binPROGRAMS:
+	-test -z "$(bin_PROGRAMS)" || rm -f $(bin_PROGRAMS)
+dlist_test$(EXEEXT): $(dlist_test_OBJECTS) $(dlist_test_DEPENDENCIES) 
+	@rm -f dlist_test$(EXEEXT)
+	$(LINK) $(dlist_test_LDFLAGS) $(dlist_test_OBJECTS) $(dlist_test_LDADD) $(LIBS)
+
+mostlyclean-compile:
+	-rm -f *.$(OBJEXT) core *.core
+
+distclean-compile:
+	-rm -f *.tab.c
+
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/dlist_test.Po@am__quote@
+
+distclean-depend:
+	-rm -rf ./$(DEPDIR)
+
+.c.o:
+@AMDEP_TRUE@	source='$<' object='$@' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@	depfile='$(DEPDIR)/$*.Po' tmpdepfile='$(DEPDIR)/$*.TPo' @AMDEPBACKSLASH@
+@AMDEP_TRUE@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(COMPILE) -c `test -f '$<' || echo '$(srcdir)/'`$<
+
+.c.obj:
+@AMDEP_TRUE@	source='$<' object='$@' libtool=no @AMDEPBACKSLASH@
+@AMDEP_TRUE@	depfile='$(DEPDIR)/$*.Po' tmpdepfile='$(DEPDIR)/$*.TPo' @AMDEPBACKSLASH@
+@AMDEP_TRUE@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(COMPILE) -c `cygpath -w $<`
+CCDEPMODE = @CCDEPMODE@
+uninstall-info-am:
+
+ETAGS = etags
+ETAGSFLAGS =
+
+tags: TAGS
+
+ID: $(HEADERS) $(SOURCES) $(LISP) $(TAGS_FILES)
+	list='$(SOURCES) $(HEADERS) $(LISP) $(TAGS_FILES)'; \
+	unique=`for i in $$list; do \
+	    if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
+	  done | \
+	  $(AWK) '    { files[$$0] = 1; } \
+	       END { for (i in files) print i; }'`; \
+	mkid -fID $$unique
+
+TAGS:  $(HEADERS) $(SOURCES)  $(TAGS_DEPENDENCIES) \
+		$(TAGS_FILES) $(LISP)
+	tags=; \
+	here=`pwd`; \
+	list='$(SOURCES) $(HEADERS)  $(LISP) $(TAGS_FILES)'; \
+	unique=`for i in $$list; do \
+	    if test -f "$$i"; then echo $$i; else echo $(srcdir)/$$i; fi; \
+	  done | \
+	  $(AWK) '    { files[$$0] = 1; } \
+	       END { for (i in files) print i; }'`; \
+	test -z "$(ETAGS_ARGS)$$tags$$unique" \
+	  || $(ETAGS) $(ETAGSFLAGS) $(AM_ETAGSFLAGS) $(ETAGS_ARGS) \
+	     $$tags $$unique
+
+GTAGS:
+	here=`$(am__cd) $(top_builddir) && pwd` \
+	  && cd $(top_srcdir) \
+	  && gtags -i $(GTAGS_ARGS) $$here
+
+distclean-tags:
+	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH
+DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
+
+top_distdir = ..
+distdir = $(top_distdir)/$(PACKAGE)-$(VERSION)
+
+distdir: $(DISTFILES)
+	@list='$(DISTFILES)'; for file in $$list; do \
+	  if test -f $$file || test -d $$file; then d=.; else d=$(srcdir); fi; \
+	  dir=`echo "$$file" | sed -e 's,/[^/]*$$,,'`; \
+	  if test "$$dir" != "$$file" && test "$$dir" != "."; then \
+	    dir="/$$dir"; \
+	    $(mkinstalldirs) "$(distdir)$$dir"; \
+	  else \
+	    dir=''; \
+	  fi; \
+	  if test -d $$d/$$file; then \
+	    if test -d $(srcdir)/$$file && test $$d != $(srcdir); then \
+	      cp -pR $(srcdir)/$$file $(distdir)$$dir || exit 1; \
+	    fi; \
+	    cp -pR $$d/$$file $(distdir)$$dir || exit 1; \
+	  else \
+	    test -f $(distdir)/$$file \
+	    || cp -p $$d/$$file $(distdir)/$$file \
+	    || exit 1; \
+	  fi; \
+	done
+check-am: all-am
+check: check-am
+all-am: Makefile $(PROGRAMS)
+
+installdirs:
+	$(mkinstalldirs) $(DESTDIR)$(bindir)
+
+install: install-am
+install-exec: install-exec-am
+install-data: install-data-am
+uninstall: uninstall-am
+
+install-am: all-am
+	@$(MAKE) $(AM_MAKEFLAGS) install-exec-am install-data-am
+
+installcheck: installcheck-am
+install-strip:
+	$(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \
+	  INSTALL_STRIP_FLAG=-s \
+	  `test -z '$(STRIP)' || \
+	    echo "INSTALL_PROGRAM_ENV=STRIPPROG='$(STRIP)'"` install
+mostlyclean-generic:
+
+clean-generic:
+
+distclean-generic:
+	-rm -f Makefile $(CONFIG_CLEAN_FILES)
+
+maintainer-clean-generic:
+	@echo "This command is intended for maintainers to use"
+	@echo "it deletes files that may require special tools to rebuild."
+clean: clean-am
+
+clean-am: clean-binPROGRAMS clean-generic mostlyclean-am
+
+distclean: distclean-am
+
+distclean-am: clean-am distclean-compile distclean-depend \
+	distclean-generic distclean-tags
+
+dvi: dvi-am
+
+dvi-am:
+
+info: info-am
+
+info-am:
+
+install-data-am:
+
+install-exec-am: install-binPROGRAMS
+
+install-info: install-info-am
+
+install-man:
+
+installcheck-am:
+
+maintainer-clean: maintainer-clean-am
+
+maintainer-clean-am: distclean-am maintainer-clean-generic
+
+mostlyclean: mostlyclean-am
+
+mostlyclean-am: mostlyclean-compile mostlyclean-generic
+
+uninstall-am: uninstall-binPROGRAMS uninstall-info-am
+
+.PHONY: GTAGS all all-am check check-am clean clean-binPROGRAMS \
+	clean-generic distclean distclean-compile distclean-depend \
+	distclean-generic distclean-tags distdir dvi dvi-am info \
+	info-am install install-am install-binPROGRAMS install-data \
+	install-data-am install-exec install-exec-am install-info \
+	install-info-am install-man install-strip installcheck \
+	installcheck-am installdirs maintainer-clean \
+	maintainer-clean-generic mostlyclean mostlyclean-compile \
+	mostlyclean-generic tags uninstall uninstall-am \
+	uninstall-binPROGRAMS uninstall-info-am
+
+# Tell versions [3.59,3.63) of GNU make to not export all variables.
+# Otherwise a system limit (for SysV at least) may be exceeded.
+.NOEXPORT:
diff --git a/test/dlist_test.c b/test/dlist_test.c
new file mode 100644
index 0000000..787df80
--- /dev/null
+++ b/test/dlist_test.c
@@ -0,0 +1,273 @@
+/*
+ * dlist_test.c
+ *
+ * Copyright (C) 2003 Eric J Bohm
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+
+/* Double linked list implementation tester.
+ */
+#include "dlist.h"
+#include <stdio.h>
+#include <string.h>
+// create some dlists put nodes in and out
+// use dump
+// try list with del_func and without
+// use insert, unshift, push
+// use pop push mark
+// use prev next
+
+typedef struct simple {
+  char label[80];
+  int number;
+} Simple;
+
+
+typedef struct complex {
+  int cnumber;
+  Simple *sthing;
+} Complex;
+
+void complex_silly_multiply_by_two( void *a);
+int complex_equal(void *a, void *b);
+int complex_less(void *a, void *b);
+int complex_greater(void *a, void *b);
+void simple_dump(Dlist *);
+void simple_dump_rev(Dlist *);
+void complex_dump(Dlist *);
+void complex_out(void *);
+void complex_del(void *);
+Complex *complex_maker(int,int,char *);
+
+Simple *simple_maker(int ,char *);
+
+int main (int argc,char *argv[])
+{
+  Dlist *list;
+  Simple *s1,*s2,*s3,*stemp;
+  Complex *c1,*c2,*c3, *ctemp, *cfound;
+  while(1)
+    {
+	s1=simple_maker(1,"one");
+	s2=simple_maker(2,"two");
+	s3=simple_maker(3,"three");
+      if((list=dlist_new(sizeof(Simple)))==NULL)	
+	{
+	   fprintf(stderr,"ERR dlist_new fail\n");
+	  return(2);
+	 }
+      dlist_push(list,s1);
+      dlist_push(list,s2);
+      dlist_push(list,s3);
+      printf("count is %ld\n",list->count);
+      simple_dump(list);
+      simple_dump_rev(list);
+      stemp=dlist_pop(list);
+      printf("popped %s\n",stemp->label);
+      simple_dump(list);
+      printf("pushed\n");
+      dlist_push(list,s3);
+      simple_dump(list);
+      stemp=dlist_shift(list);
+      printf("shifted %s\n",stemp->label);
+      simple_dump(list);
+      printf("unshifted\n");
+      dlist_unshift(list,stemp);
+      simple_dump(list);
+      dlist_destroy(list);
+      c1=complex_maker(1,1,"one");
+      c2=complex_maker(2,2,"two");
+      c3=complex_maker(3,3,"three");
+      if((list=dlist_new_with_delete(sizeof(Complex),complex_del))==NULL)
+	{
+		fprintf(stderr,"ERR dlist_new fail\n");
+		return(2);
+	}
+	if(dlist_insert_sorted(list,c1,complex_less)==NULL)
+	{
+		fprintf(stderr,"ERR dlist_insert fail\n");
+		return(2);
+	}
+	printf("sorted insert 1\n");
+	if(dlist_insert_sorted(list,c3,complex_less)==NULL)
+	{
+		fprintf(stderr,"ERR dlist_insert fail\n");
+		return(2);
+	}
+	if(dlist_insert_sorted(list,c2,complex_less)==NULL)
+	{
+		fprintf(stderr,"ERR dlist_insert fail\n");
+		return(2);
+	}
+	printf("sorted insert 2\n");
+	printf("ascending sorted output\n");
+	complex_dump(list);
+	dlist_transform(list,complex_silly_multiply_by_two);
+	printf("transform multi by 2 output\n");
+	complex_dump(list);
+	ctemp=complex_maker(6,6,"three");
+	if((cfound=(Complex *) dlist_find_custom(list,ctemp,complex_equal))!=NULL)
+
+	{
+		printf("found %d as %d in list\n",ctemp->cnumber,cfound->cnumber);
+	} else {
+		printf("ERROR find failed on %d \n",ctemp->cnumber);
+		return(3);
+	}
+	complex_del(ctemp);
+	dlist_destroy(list);
+	c1=complex_maker(1,1,"one");
+	c2=complex_maker(2,2,"two");
+	c3=complex_maker(3,3,"three");
+      if((list=dlist_new_with_delete(sizeof(Complex),complex_del))==NULL)
+	{
+	   fprintf(stderr,"ERR dlist_new fail\n");
+	  return(2);
+	 }
+	if(dlist_insert_sorted(list,c1,complex_greater)==NULL)
+	{
+	  fprintf(stderr,"ERR dlist_insert fail\n");
+	  return(2);
+	}
+	printf("greater sorted insert 1\n");
+	if(dlist_insert_sorted(list,c3,complex_greater)==NULL)
+	{
+	   fprintf(stderr,"ERR dlist_insert fail\n");
+	   return(2);
+	 }
+	printf("greater sorted insert 3\n");
+	if(dlist_insert_sorted(list,c2,complex_greater)==NULL)
+	{
+	   fprintf(stderr,"ERR dlist_insert fail\n");
+	   return(2);
+	 }
+	printf("greater sorted insert 2\n");
+	printf("descending sorted output using transform\n");
+	dlist_transform(list,complex_out);
+      dlist_destroy(list);
+    }
+  return(0);
+}
+
+void simple_dump (Dlist *list)
+{
+  Simple *thisone;
+  printf("count  %ld \n",list->count);
+  dlist_for_each_data(list,thisone,Simple)
+    {
+      printf("label %s number %d \n",thisone->label,thisone->number);
+    }
+
+}
+void simple_dump_rev (Dlist *list)
+{
+  Simple *thisone;
+  printf("rev count  %ld \n",list->count);
+  dlist_for_each_data_rev(list,thisone,Simple)
+    {
+      printf("label %s number %d \n",thisone->label,thisone->number);
+    }
+}
+
+Simple * simple_maker(int snumber,char *label)
+{
+	Simple *stemp;
+	if((stemp=malloc(sizeof(Simple)))==NULL)
+	{
+		fprintf(stderr,"ERR malloc fail\n");
+		return(NULL);
+	}
+	stemp->number=snumber;
+	strcpy(stemp->label,label);
+	return(stemp);
+}
+
+Complex * complex_maker(int cnumber, int snumber, char* label)
+{
+	Complex *ctemp;
+	if((ctemp=malloc(sizeof(Complex)))==NULL)
+	{
+		fprintf(stderr,"ERR malloc fail\n");
+		return(NULL);
+	}
+	ctemp->cnumber=cnumber;
+	ctemp->sthing=simple_maker(snumber,label);
+	return(ctemp);
+}
+
+void complex_out(void *data)
+{
+	Complex *thisone=(Complex *)data;
+	printf("cnumber %d label %s number %d \n",thisone->cnumber,thisone->sthing->label,thisone->sthing->number);
+}
+
+/**
+ * return 1 if a==b, else 0
+ */
+int complex_equal(void *a, void *b)
+{
+	if((((Complex *)a)->cnumber==((Complex *)b)->cnumber)
+	    && (((Complex *)a)->sthing->number==
+		((Complex *)b)->sthing->number)
+	    &&  strcmp(((Complex *)a)->sthing->label,
+		((Complex *)b)->sthing->label)==0)
+		return(1);
+	return(0);
+}
+
+/** for sorting
+ * return 1 if a<b, else 0
+ */
+int complex_less(void *a, void *b)
+{
+	return( ((Complex *)a)->cnumber <  ((Complex *)b)->cnumber );
+}
+
+/** for sorting
+ * return 1 if a>b, else 0
+ */
+int complex_greater(void *a, void *b)
+{
+	return( ((Complex *)a)->cnumber >  ((Complex *)b)->cnumber );
+}
+
+void complex_silly_multiply_by_two( void *a)
+{
+	((Complex *)a)->cnumber=((Complex *)a)->cnumber*2;
+	((Complex *)a)->sthing->number=((Complex *)a)->sthing->number*2;
+}
+
+void complex_dump (Dlist *list)
+{
+  Complex *thisone;
+  dlist_start(list);
+  printf("count  %ld \n",list->count);
+  dlist_for_each_data(list,thisone,Complex)
+    {
+      printf("cnumber %d label %s number %d \n",thisone->cnumber,thisone->sthing->label,thisone->sthing->number);
+    }
+
+}
+
+void complex_del (void *item)
+{
+  Complex *corpse=item;
+  printf("freeing complex\n");
+  free(corpse->sthing);
+  free(corpse);
+}