Fully integrate libsysfs into NetNuke (it compiles and links correctly)

1 files changed, 1071 insertions, 0 deletions

diff --git a/libsysfs/sysfs_dir.c b/libsysfs/sysfs_dir.c
new file mode 100644
index 0000000..5276991
--- /dev/null
+++ b/libsysfs/sysfs_dir.c
@@ -0,0 +1,1071 @@
+/*
+ * sysfs_dir.c
+ *
+ * Directory utility functions for libsysfs
+ *
+ * Copyright (C) IBM Corp. 2003
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  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
+ *
+ */
+#include "libsysfs.h"
+#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(((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(((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(((char *)a), ((struct sysfs_directory *)b)->name) == 0)
+		return 1;
+
+	return 0;
+}
+
+/**
+ * sysfs_close_attribute: closes and cleans up attribute
+ * @sysattr: attribute to close.
+ */
+void sysfs_close_attribute(struct sysfs_attribute *sysattr)
+{
+	if (sysattr != NULL) {
+		if (sysattr->value != NULL)
+			free(sysattr->value);
+		free(sysattr);
+	}
+}
+
+/**
+ * alloc_attribute: allocates and initializes attribute structure
+ * returns struct sysfs_attribute with success and NULL with error.
+ */
+static struct sysfs_attribute *alloc_attribute(void)
+{
+	return (struct sysfs_attribute *)
+			calloc(1, sizeof(struct sysfs_attribute));
+}
+
+/**
+ * sysfs_open_attribute: creates sysfs_attribute structure
+ * @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 *sysattr = NULL;
+	struct stat fileinfo;
+	
+	if (path == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+	sysattr = alloc_attribute();
+	if (sysattr == NULL) {
+		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 attrib name from path: %s\n", path);
+		sysfs_close_attribute(sysattr);
+		return NULL;
+	}
+	safestrcpy(sysattr->path, path);
+	if ((stat(sysattr->path, &fileinfo)) != 0) {
+		dprintf("Stat failed: No such attribute?\n");
+		sysattr->method = 0;
+		free(sysattr);
+		sysattr = NULL;
+	} else {
+		if (fileinfo.st_mode & S_IRUSR)
+			sysattr->method |= SYSFS_METHOD_SHOW;
+		if (fileinfo.st_mode & S_IWUSR)
+			sysattr->method |= SYSFS_METHOD_STORE;
+	}
+
+	return sysattr;
+}
+
+/**
+ * sysfs_write_attribute: write value to the attribute
+ * @sysattr: attribute to write
+ * @new_value: value to write
+ * @len: length of "new_value"
+ * returns 0 with success and -1 with error.
+ */
+int sysfs_write_attribute(struct sysfs_attribute *sysattr,
+		const char *new_value, size_t len)
+{
+	int fd;
+	int length;
+	
+	if (sysattr == NULL || new_value == NULL || len == 0) {
+		errno = EINVAL;
+		return -1;
+	}
+	
+	if (!(sysattr->method & SYSFS_METHOD_STORE)) {
+		dprintf ("Store method not supported for attribute %s\n",
+			sysattr->path);
+		errno = EACCES;
+		return -1;
+	}
+	if (sysattr->method & SYSFS_METHOD_SHOW) {
+		/*
+		 * read attribute again to see if we can get an updated value 
+		 */
+		if ((sysfs_read_attribute(sysattr)) != 0) {
+			dprintf("Error reading attribute\n");
+			return -1;
+		}
+		if ((strncmp(sysattr->value, new_value, sysattr->len)) == 0) {
+			dprintf("Attr %s already has the requested value %s\n",
+					sysattr->name, new_value);
+			return 0;	
+		}
+	}
+	/* 
+	 * open O_WRONLY since some attributes have no "read" but only
+	 * "write" permission 
+	 */ 
+	if ((fd = open(sysattr->path, O_WRONLY)) < 0) {
+		dprintf("Error reading attribute %s\n", sysattr->path);
+		return -1;
+	}
+
+	length = write(fd, new_value, len);
+	if (length < 0) {
+		dprintf("Error writing to the attribute %s - invalid value?\n",
+			sysattr->name);
+		close(fd);
+		return -1;
+	} else if ((unsigned int)length != len) {
+		dprintf("Could not write %d bytes to attribute %s\n", 
+					len, sysattr->name);
+		/* 
+		 * since we could not write user supplied number of bytes,
+		 * restore the old value if one available
+		 */
+		if (sysattr->method & SYSFS_METHOD_SHOW) {
+			length = write(fd, sysattr->value, sysattr->len);
+			close(fd);
+			return -1;
+		}
+	}
+	
+	/*
+	 * Validate length that has been copied. Alloc appropriate area
+	 * in sysfs_attribute. Verify first if the attribute supports reading
+	 * (show method). If it does not, do not bother
+	 */ 
+	if (sysattr->method & SYSFS_METHOD_SHOW) {
+		if (length != sysattr->len) {
+			sysattr->value = (char *)realloc
+				(sysattr->value, length);
+			sysattr->len = length;
+			safestrcpymax(sysattr->value, new_value, length);
+		} else {
+			/*"length" of the new value is same as old one */ 
+			safestrcpymax(sysattr->value, new_value, length);
+		}
+	}
+			
+	close(fd);	
+	return 0;
+}
+
+/**
+ * sysfs_read_attribute: reads value from attribute
+ * @sysattr: attribute to read
+ * returns 0 with success and -1 with error.
+ */
+int sysfs_read_attribute(struct sysfs_attribute *sysattr)
+{
+	char *fbuf = NULL;
+	char *vbuf = NULL;
+	ssize_t length = 0;
+	long pgsize = 0;
+	int fd;
+
+	if (sysattr == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	if (!(sysattr->method & SYSFS_METHOD_SHOW)) {
+		dprintf("Show method not supported for attribute %s\n",
+			sysattr->path);
+		errno = EACCES;
+		return -1;
+	}
+	pgsize = sysconf(_SC_PAGESIZE);
+	fbuf = (char *)calloc(1, pgsize+1);
+	if (fbuf == NULL) {
+		dprintf("calloc failed\n");
+		return -1;
+	}
+	if ((fd = open(sysattr->path, O_RDONLY)) < 0) {
+		dprintf("Error reading attribute %s\n", sysattr->path);
+		free(fbuf);
+		return -1;
+	}
+	length = read(fd, fbuf, pgsize);
+	if (length < 0) {
+		dprintf("Error reading from attribute %s\n", sysattr->path);
+		close(fd);
+		free(fbuf);
+		return -1;
+	}
+	if (sysattr->len > 0) {
+		if ((sysattr->len == length) && 
+				(!(strncmp(sysattr->value, fbuf, length)))) {
+			close(fd);
+			free(fbuf);
+			return 0;
+		}
+		free(sysattr->value);
+	}
+	sysattr->len = length;
+	close(fd);
+	vbuf = (char *)realloc(fbuf, length+1);
+	if (vbuf == NULL) {
+		dprintf("realloc failed\n");
+		free(fbuf);
+		return -1;
+	}
+	sysattr->value = vbuf;
+
+	return 0;
+}
+
+/**
+ * sysfs_read_attribute_value: given path to attribute, return its value.
+ *	values can be up to a pagesize, if buffer is smaller the value will 
+ *	be truncated. 
+ * @attrpath: sysfs path to attribute
+ * @value: buffer to put value
+ * @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)
+{
+	struct sysfs_attribute *attr = NULL;
+	size_t length = 0;
+
+	if (attrpath == NULL || value == NULL || vsize == 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	attr = sysfs_open_attribute(attrpath);
+	if (attr == NULL) {
+		dprintf("Invalid attribute path %s\n", attrpath);
+		errno = EINVAL;
+		return -1;
+	}
+	if((sysfs_read_attribute(attr)) != 0 || attr->value == NULL) {
+		dprintf("Error reading from attribute %s\n", attrpath);
+		sysfs_close_attribute(attr);
+		return -1;
+	}
+	length = strlen(attr->value);
+	if (length > vsize) 
+		dprintf("Value length %d is larger than supplied buffer %d\n",
+			length, vsize);
+	safestrcpymax(value, attr->value, vsize);
+	sysfs_close_attribute(attr);
+
+	return 0;
+}
+
+/**
+ * sysfs_get_value_from_attrbutes: given a linked list of attributes and an 
+ * 	attribute name, return its value
+ * @attr: attribute to search
+ * @name: name to look for
+ * returns char * value - could be NULL
+ */
+char *sysfs_get_value_from_attributes(struct dlist *attr, const char *name)
+{	
+	struct sysfs_attribute *cur = NULL;
+	
+	if (attr == NULL || name == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+	dlist_for_each_data(attr, cur, struct sysfs_attribute) {
+		if (strcmp(cur->name, name) == 0)
+			return cur->value;
+	}
+	return NULL;
+}
+
+/**
+ * sysfs_close_link: closes and cleans up link.
+ * @ln: link to close.
+ */
+void sysfs_close_link(struct sysfs_link *ln)
+{
+	if (ln != NULL) 
+		free(ln);
+}
+
+/**
+ * sysfs_close_directory: closes directory, cleans up attributes and links
+ * @sysdir: sysfs_directory to close
+ */
+void sysfs_close_directory(struct sysfs_directory *sysdir)
+{
+	if (sysdir != NULL) {
+		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);
+		sysdir = NULL;
+	}
+}
+
+/**
+ * alloc_directory: allocates and initializes directory structure
+ * returns struct sysfs_directory with success or NULL with error.
+ */
+static struct sysfs_directory *alloc_directory(void)
+{
+	return (struct sysfs_directory *)
+			calloc(1, sizeof(struct sysfs_directory));
+}
+
+/**
+ * alloc_link: allocates and initializes link structure
+ * returns struct sysfs_link with success or NULL with error.
+ */
+static struct sysfs_link *alloc_link(void)
+{
+	return (struct sysfs_link *)calloc(1, sizeof(struct sysfs_link));
+}
+
+/**
+ * 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;
+	int retval = 0;
+
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	if (sysdir->subdirs == NULL) 
+		if ((sysfs_read_dir_subdirs(sysdir)) != 0) 
+			return 0;
+	if (sysdir->subdirs != NULL) {
+		dlist_for_each_data(sysdir->subdirs, cursub, 
+						struct sysfs_directory) {
+			if ((sysfs_read_dir_subdirs(cursub)) != 0) {
+				dprintf ("Error reading subdirectory %s\n",
+						cursub->name);
+				retval = -1;
+			}
+		}
+	}
+	if (!retval)
+		errno = 0;
+	return retval;
+}
+
+/**
+ * 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 *sdir = NULL;
+
+	if (path == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (sysfs_path_is_dir(path) != 0) {
+		dprintf("Invalid path to directory %s\n", path);
+		errno = EINVAL;
+		return NULL;
+	}
+
+	sdir = alloc_directory();
+	if (sdir == NULL) {
+		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;
+	}
+	safestrcpy(sdir->path, path);
+
+	return sdir;
+}
+
+/**
+ * sysfs_open_link: opens a sysfs link, creates struct, and returns
+ * @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 *ln = NULL;
+
+	if (linkpath == NULL || strlen(linkpath) > SYSFS_PATH_MAX) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	ln = alloc_link();
+	if (ln == NULL) {
+		dprintf("Error allocating link %s\n", linkpath);
+		return NULL;
+	}
+	safestrcpy(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) {
+		sysfs_close_link(ln);
+		errno = EINVAL;
+		dprintf("Invalid link path %s\n", linkpath);
+		return NULL;
+	}
+
+	return ln;
+}
+
+/**
+ * add_attribute: open and add attribute at path to given directory
+ * @sysdir: directory to add attribute to
+ * @path: path to attribute
+ * returns 0 with success and -1 with error.
+ */
+static int add_attribute(struct sysfs_directory *sysdir, const char *path)
+{
+	struct sysfs_attribute *attr = NULL;
+
+	attr = sysfs_open_attribute(path);
+	if (attr == NULL) {
+		dprintf("Error opening attribute %s\n",	path);
+		return -1;
+	}
+	if (attr->method & SYSFS_METHOD_SHOW) {
+		if ((sysfs_read_attribute(attr)) != 0) {
+			dprintf("Error reading attribute %s\n",	path);
+			sysfs_close_attribute(attr);
+			return 0;
+		}
+	}
+			                        
+	if (sysdir->attributes == NULL) {
+		sysdir->attributes = dlist_new_with_delete
+			(sizeof(struct sysfs_attribute), sysfs_del_attribute);
+	}
+	dlist_unshift_sorted(sysdir->attributes, attr, sort_list);
+
+	return 0;
+}
+
+/**
+ * add_subdirectory: open and add subdirectory at path to given directory
+ * @sysdir: directory to add subdir to
+ * @path: path to subdirectory
+ * returns 0 with success and -1 with error.
+ */
+static int add_subdirectory(struct sysfs_directory *sysdir, const char *path)
+{
+	struct sysfs_directory *subdir = NULL;
+
+	subdir = sysfs_open_directory(path);
+	if (subdir == NULL) {
+		dprintf("Error opening directory %s\n", path);
+		return -1;
+	}
+	if (sysdir->subdirs == NULL)
+		sysdir->subdirs = dlist_new_with_delete
+			(sizeof(struct sysfs_directory), sysfs_del_directory);
+	dlist_unshift_sorted(sysdir->subdirs, subdir, sort_list);
+	return 0;
+}
+
+/**
+ * add_link: open and add link at path to given directory
+ * @sysdir: directory to add link to
+ * @path: path to link
+ * returns 0 with success and -1 with error.
+ */
+static int add_link(struct sysfs_directory *sysdir, const char *path)
+{
+	struct sysfs_link *ln = NULL;
+
+	ln = sysfs_open_link(path);
+	if (ln == NULL) {
+		dprintf("Error opening link %s\n", path);
+		return -1;
+	}
+	if (sysdir->links == NULL)
+		sysdir->links = dlist_new_with_delete
+				(sizeof(struct sysfs_link), sysfs_del_link);
+	dlist_unshift_sorted(sysdir->links, ln, sort_list);
+	return 0;
+}
+
+/**
+ * sysfs_read_dir_attributes: grabs attributes for the given directory
+ * @sysdir: sysfs directory to open
+ * returns 0 with success and -1 with error.
+ */
+int sysfs_read_dir_attributes(struct sysfs_directory *sysdir)
+{
+	DIR *dir = NULL;
+	struct dirent *dirent = NULL;
+	char file_path[SYSFS_PATH_MAX];
+	int retval = 0;
+
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	dir = opendir(sysdir->path);
+	if (dir == NULL) {
+		dprintf("Error opening directory %s\n", sysdir->path);
+		return -1;
+	}
+	while(((dirent = readdir(dir)) != NULL) && retval == 0) {
+		if (0 == strcmp(dirent->d_name, "."))
+			 continue;
+		if (0 == strcmp(dirent->d_name, ".."))
+			continue;
+		memset(file_path, 0, SYSFS_PATH_MAX);
+		safestrcpy(file_path, sysdir->path);
+		safestrcat(file_path, "/");
+		safestrcat(file_path, dirent->d_name);
+		if ((sysfs_path_is_file(file_path)) == 0)
+			retval = add_attribute(sysdir, file_path);
+	}
+	closedir(dir);
+	if (!retval)
+		errno = 0;
+	return(retval);
+}
+
+/**
+ * sysfs_read_dir_links: grabs links in a specific directory
+ * @sysdir: sysfs directory to read links
+ * returns 0 with success and -1 with error.
+ */
+int sysfs_read_dir_links(struct sysfs_directory *sysdir)
+{
+	DIR *dir = NULL;
+	struct dirent *dirent = NULL;
+	char file_path[SYSFS_PATH_MAX];
+	int retval = 0;
+
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	dir = opendir(sysdir->path);
+	if (dir == NULL) {
+		dprintf("Error opening directory %s\n", sysdir->path);
+		return -1;
+	}
+	while(((dirent = readdir(dir)) != NULL) && retval == 0) {
+		if (0 == strcmp(dirent->d_name, "."))
+			 continue;
+		if (0 == strcmp(dirent->d_name, ".."))
+			continue;
+		memset(file_path, 0, SYSFS_PATH_MAX);
+		safestrcpy(file_path, sysdir->path);
+		safestrcat(file_path, "/");
+		safestrcat(file_path, dirent->d_name);
+		if ((sysfs_path_is_link(file_path)) == 0) {
+			retval = add_link(sysdir, file_path);
+			if (retval != 0)
+				break;
+		}
+	}
+	closedir(dir);
+	if (!retval)
+		errno = 0;
+	return(retval);
+}
+
+/**
+ * sysfs_read_dir_subdirs: grabs subdirs in a specific directory
+ * @sysdir: sysfs directory to read links
+ * returns 0 with success and -1 with error.
+ */
+int sysfs_read_dir_subdirs(struct sysfs_directory *sysdir)
+{
+	DIR *dir = NULL;
+	struct dirent *dirent = NULL;
+	char file_path[SYSFS_PATH_MAX];
+	int retval = 0;
+
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	dir = opendir(sysdir->path);
+	if (dir == NULL) {
+		dprintf("Error opening directory %s\n", sysdir->path);
+		return -1;
+	}
+	while(((dirent = readdir(dir)) != NULL) && retval == 0) {
+		if (0 == strcmp(dirent->d_name, "."))
+			 continue;
+		if (0 == strcmp(dirent->d_name, ".."))
+			continue;
+		memset(file_path, 0, SYSFS_PATH_MAX);
+		safestrcpy(file_path, sysdir->path);
+		safestrcat(file_path, "/");
+		safestrcat(file_path, dirent->d_name);
+		if ((sysfs_path_is_dir(file_path)) == 0)
+			retval = add_subdirectory(sysdir, file_path);
+	}
+	closedir(dir);
+	if (!retval)
+		errno = 0;
+	return(retval);
+}
+
+/**
+ * sysfs_read_directory: grabs attributes, links, and subdirectories
+ * @sysdir: sysfs directory to open
+ * returns 0 with success and -1 with error.
+ */
+int sysfs_read_directory(struct sysfs_directory *sysdir)
+{
+	DIR *dir = NULL;
+	struct dirent *dirent = NULL;
+	struct stat astats;
+	char file_path[SYSFS_PATH_MAX];
+	int retval = 0;
+
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	dir = opendir(sysdir->path);
+	if (dir == NULL) {
+		dprintf("Error opening directory %s\n", sysdir->path);
+		return -1;
+	}
+	while(((dirent = readdir(dir)) != NULL) && retval == 0) {
+		if (0 == strcmp(dirent->d_name, "."))
+			 continue;
+		if (0 == strcmp(dirent->d_name, ".."))
+			continue;
+		memset(file_path, 0, SYSFS_PATH_MAX);
+		safestrcpy(file_path, sysdir->path);
+		safestrcat(file_path, "/");
+		safestrcat(file_path, dirent->d_name);
+		if ((lstat(file_path, &astats)) != 0) {
+			dprintf("stat failed\n");
+			continue;
+		}
+		if (S_ISDIR(astats.st_mode)) 
+			retval = add_subdirectory(sysdir, file_path);
+
+		else if (S_ISLNK(astats.st_mode))
+			retval = add_link(sysdir, file_path);
+
+		else if (S_ISREG(astats.st_mode))
+			retval = add_attribute(sysdir, file_path);
+	}
+	closedir(dir);
+	if (!retval)
+		errno = 0;
+	return(retval);
+}
+
+/**
+ * sysfs_refresh_dir_attributes: Refresh attributes list
+ * @sysdir: directory whose list of attributes to refresh
+ * Returns 0 on success, 1 on failure
+ */
+int sysfs_refresh_dir_attributes(struct sysfs_directory *sysdir)
+{
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return 1;
+	}
+	if ((sysfs_path_is_dir(sysdir->path)) != 0) {
+		dprintf("Invalid path to directory %s\n", sysdir->path);
+		errno = EINVAL;
+		return 1;
+	}
+	if (sysdir->attributes != NULL) {
+		dlist_destroy(sysdir->attributes);
+		sysdir->attributes = NULL;
+	}
+	if ((sysfs_read_dir_attributes(sysdir)) != 0) {
+		dprintf("Error refreshing attributes for directory %s\n", 
+							sysdir->path);
+		return 1;
+	}
+	errno = 0;
+	return 0;
+}
+
+/**
+ * sysfs_refresh_dir_links: Refresh links list
+ * @sysdir: directory whose list of links to refresh
+ * Returns 0 on success, 1 on failure
+ */
+int sysfs_refresh_dir_links(struct sysfs_directory *sysdir)
+{
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return 1;
+	}
+	if ((sysfs_path_is_dir(sysdir->path)) != 0) {
+		dprintf("Invalid path to directory %s\n", sysdir->path);
+		errno = EINVAL;
+		return 1;
+	}
+	if (sysdir->links != NULL) {
+		dlist_destroy(sysdir->links);
+		sysdir->links = NULL;
+	}
+	if ((sysfs_read_dir_links(sysdir)) != 0) {
+		dprintf("Error refreshing links for directory %s\n", 
+							sysdir->path);
+		return 1;
+	}
+	errno = 0;
+	return 0;
+}
+
+/**
+ * sysfs_refresh_dir_subdirs: Refresh subdirs list
+ * @sysdir: directory whose list of subdirs to refresh
+ * Returns 0 on success, 1 on failure
+ */
+int sysfs_refresh_dir_subdirs(struct sysfs_directory *sysdir)
+{
+	if (sysdir == NULL) {
+		errno = EINVAL;
+		return 1;
+	}
+	if ((sysfs_path_is_dir(sysdir->path)) != 0) {
+		dprintf("Invalid path to directory %s\n", sysdir->path);
+		errno = EINVAL;
+		return 1;
+	}
+	if (sysdir->subdirs != NULL) {
+		dlist_destroy(sysdir->subdirs);
+		sysdir->subdirs = NULL;
+	}
+	if ((sysfs_read_dir_subdirs(sysdir)) != 0) {
+		dprintf("Error refreshing subdirs for directory %s\n", 
+							sysdir->path);
+		return 1;
+	}
+	errno = 0;
+	return 0;
+}
+
+/**
+ * sysfs_get_directory_attribute: retrieves attribute attrname from current
+ *	directory only
+ * @dir: directory to retrieve attribute from
+ * @attrname: name of attribute to look for
+ *
+ * NOTE: Since we know the attribute to look for, this routine looks for the
+ * 	attribute if it was created _after_ the attrlist was read initially.
+ * 	
+ * returns sysfs_attribute if found and NULL if not found
+ */
+struct sysfs_attribute *sysfs_get_directory_attribute
+			(struct sysfs_directory *dir, char *attrname)
+{
+	struct sysfs_attribute *attr = NULL;
+	char new_path[SYSFS_PATH_MAX];
+	
+	if (dir == NULL || attrname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (dir->attributes == NULL) 
+		if ((sysfs_read_dir_attributes(dir) != 0) 
+		    || (dir->attributes == NULL))
+			return NULL;
+
+	attr = (struct sysfs_attribute *)dlist_find_custom
+			(dir->attributes, attrname, dir_attribute_name_equal);
+	if (attr != NULL) {
+		if ((attr->method & SYSFS_METHOD_SHOW) &&
+			(sysfs_read_attribute(attr)) != 0) {
+			dprintf("Error reading attribute %s\n", attr->name);
+			return NULL;
+		}
+	} else {
+		memset(new_path, 0, SYSFS_PATH_MAX);
+		safestrcpy(new_path, dir->path);
+		safestrcat(new_path, "/");
+		safestrcat(new_path, attrname);
+		if ((sysfs_path_is_file(new_path)) == 0) {
+			if ((add_attribute(dir, new_path)) == 0) {
+				attr = (struct sysfs_attribute *)
+					dlist_find_custom(dir->attributes,
+					attrname, dir_attribute_name_equal);
+			}
+		}
+	}
+		
+	return attr;
+}
+
+/**
+ * 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, char *linkname)
+{
+	if (dir == NULL || linkname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+	if (dir->links == NULL) {
+		if ((sysfs_read_dir_links(dir) != 0) || (dir->links == NULL))
+			return NULL;
+	} else {
+		if ((sysfs_refresh_dir_links(dir)) != 0) 
+			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,
+						char *subname)
+{
+	struct sysfs_directory *sub = NULL, *cursub = NULL;
+
+	if (dir == NULL || subname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (dir->subdirs == NULL)
+		if (sysfs_read_dir_subdirs(dir) != 0)
+			return NULL;
+
+	sub = (struct sysfs_directory *)dlist_find_custom(dir->subdirs,
+		subname, dir_subdir_name_equal);
+	if (sub != NULL) 
+		return sub;
+
+	if (dir->subdirs != NULL) {
+		dlist_for_each_data(dir->subdirs, cursub, 
+					struct sysfs_directory) {
+			if (cursub->subdirs == NULL) {
+				if (sysfs_read_dir_subdirs(cursub) != 0)
+					continue;
+				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,
+						char *linkname)
+{
+	struct sysfs_directory *cursub = NULL;
+	struct sysfs_link *ln = NULL;
+
+	if (dir == NULL || linkname == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	ln = sysfs_get_directory_link(dir, linkname);
+	if (ln != NULL)
+		return ln;
+
+	if (dir->subdirs == NULL) 
+		if (sysfs_read_dir_subdirs(dir) != 0)
+			return NULL;
+
+	if (dir->subdirs != NULL) {
+		dlist_for_each_data(dir->subdirs, cursub, 
+						struct sysfs_directory) {
+			ln = sysfs_get_subdirectory_link(cursub, linkname);
+			if (ln != NULL)
+				return ln;
+		}
+	}
+	return NULL;
+}
+
+/**
+ * sysfs_get_dir_attributes: returns dlist of directory attributes
+ * @dir: directory to retrieve attributes from
+ * returns dlist of attributes or NULL
+ */
+struct dlist *sysfs_get_dir_attributes(struct sysfs_directory *dir)
+{
+	if (dir == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (dir->attributes == NULL) {
+		if (sysfs_read_dir_attributes(dir) != 0)
+			return NULL;
+	}
+
+	return (dir->attributes);
+}
+
+/**
+ * sysfs_get_dir_links: returns dlist of directory links
+ * @dir: directory to return links for
+ * returns dlist of links or NULL
+ */
+struct dlist *sysfs_get_dir_links(struct sysfs_directory *dir)
+{
+	if (dir == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (dir->links == NULL) {
+		if (sysfs_read_dir_links(dir) != 0)
+			return NULL;
+	}
+
+	return (dir->links);
+}
+
+/**
+ * sysfs_get_dir_subdirs: returns dlist of directory subdirectories
+ * @dir: directory to return subdirs for
+ * returns dlist of subdirs or NULL
+ */
+struct dlist *sysfs_get_dir_subdirs(struct sysfs_directory *dir)
+{
+	if (dir == NULL) {
+		errno = EINVAL;
+		return NULL;
+	}
+
+	if (dir->subdirs == NULL) {
+		if (sysfs_read_dir_subdirs(dir) != 0)
+			return NULL;
+	}
+
+	return (dir->subdirs);
+}