1 files changed, 156 insertions, 0 deletions
diff --git a/lib/sysfs_utils.c b/lib/sysfs_utils.c
new file mode 100644
index 0000000..a2410ab
--- /dev/null
+++ b/lib/sysfs_utils.c
@@ -0,0 +1,156 @@
+/*
+ * syfs_utils.c
+ *
+ * System utility functions for libsysfs
+ *
+ * Copyright (C) 2003 International Business Machines, Inc.
+ *
+ *  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_get_mnt_path: Gets the mount point for specified filesystem.
+ * @fs_type: filesystem type to retrieve mount point
+ * @mnt_path: place to put the retrieved mount path
+ * @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)
+{
+	FILE *mnt;
+	struct mntent *mntent;
+	int ret = 0;
+	size_t dirlen = 0;
+
+	/* check arg */
+	if (fs_type == NULL || mnt_path == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if ((mnt = setmntent(SYSFS_PROC_MNTS, "r")) == NULL) {
+		dprintf(stderr, "Error getting mount information\n");
+		return -1;
+	}
+	while (ret == 0 && dirlen == 0 && (mntent = getmntent(mnt)) != NULL) {
+		if (strcmp(mntent->mnt_type, fs_type) == 0) {
+			dirlen = strlen(mntent->mnt_dir);
+			if (dirlen <= (len - 1)) {
+				strcpy(mnt_path, mntent->mnt_dir);
+			} else {
+				dprintf(stderr, 
+					"Error - mount path too long\n");
+				ret = -1;
+			}
+		}
+	}
+	endmntent(mnt);
+	if (dirlen == 0 && ret == 0) {
+		dprintf(stderr, "Filesystem %s not found!\n", fs_type);
+		errno = EINVAL;
+		ret = -1;
+	}
+	return ret;
+}
+
+/*
+ * sysfs_get_mnt_path: Gets the sysfs mount point.
+ * @mnt_path: place to put "sysfs" mount point
+ * @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 ret = -1;
+
+	if (mnt_path != NULL)
+		ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
+	else
+		errno = EINVAL;
+
+	return ret;
+}
+
+/**
+ * sysfs_get_name_from_path: returns last name from a "/" delimited path
+ * @path: path to get name from
+ * @name: where to put name
+ * @len: size of name
+ */
+int sysfs_get_name_from_path(const char *path, char *name, size_t len)
+{
+	char *n = NULL;
+                                                                                
+	if (path == NULL || name == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	n = strrchr(path, '/');
+	if (n == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+	n++;
+	strncpy(name, n, len);
+
+	return 0;
+}
+
+/**
+ * sysfs_get_link: returns link source
+ * @path: symbolic link's path
+ * @target: where to put name
+ * @len: size of name
+ */
+int sysfs_get_link(const char *path, char *target, size_t len)
+{
+	char devdir[SYSFS_PATH_MAX];
+	char linkpath[SYSFS_PATH_MAX];
+	char *d = NULL;
+
+	if (path == NULL || target == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	memset(devdir, 0, SYSFS_PATH_MAX);
+	memset(linkpath, 0, SYSFS_PATH_MAX);
+
+	if ((sysfs_get_mnt_path(devdir, SYSFS_PATH_MAX)) != 0) {
+		dprintf(stderr, "Sysfs not supported on this system\n");
+		return -1;
+	}
+								        
+	if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
+		return -1;
+	}
+									        
+	d = linkpath;
+
+	/* getting rid of leading "../.." */	
+	while (*d == '/' || *d == '.')
+		d++;
+
+	d--;
+	
+	strcat(devdir, d);
+	strncpy(target, devdir, len);
+
+	return 0;
+}