Fix sysfs handling of block:sdX and scsi bus changes

This has us use the udev_sysfs code instead of hacking our own.
There are two items that need future proofing:
1. handling of iscsi_session class device symlinks
2. scanning opens /sys/class/iscsi_* dir instead of doing
a proper search like udev_sysfs.

1 files changed, 53 insertions, 0 deletions

diff --git a/usr/sysfs.h b/usr/sysfs.h
new file mode 100644
index 0000000..af25ccc
--- /dev/null
+++ b/usr/sysfs.h
@@ -0,0 +1,53 @@
+/*
+ * This is from udev-121 udev.h
+ *
+ * Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (C) 2003-2006 Kay Sievers <kay.sievers@vrfy.org>
+ *
+ *	This program is free software; you can redistribute it and/or modify it
+ *	under the terms of the GNU General Public License as published by the
+ *	Free Software Foundation version 2 of the License.
+ *
+ *	This program 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
+ *	General Public License for more details.
+ *
+ *	You should have received a copy of the GNU General Public License along
+ *	with this program; if not, write to the Free Software Foundation, Inc.,
+ *	51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ */
+
+#ifndef _SYSFS_
+#define _SYSFS_
+
+#include "list.h"
+#include "string.h"
+
+#define PATH_SIZE				512
+#define NAME_SIZE				256
+
+struct sysfs_device {
+	struct list_head node;			/* for device cache */
+	struct sysfs_device *parent;		/* already cached parent*/
+	char devpath[PATH_SIZE];
+	char subsystem[NAME_SIZE];		/* $class, $bus, drivers, module */
+	char kernel[NAME_SIZE];			/* device instance name */
+	char kernel_number[NAME_SIZE];
+	char driver[NAME_SIZE];			/* device driver name */
+};
+
+extern char sysfs_path[PATH_SIZE];
+extern int sysfs_init(void);
+extern void sysfs_cleanup(void);
+extern void sysfs_device_set_values(struct sysfs_device *dev, const char *devpath,
+				    const char *subsystem, const char *driver);
+extern struct sysfs_device *sysfs_device_get(const char *devpath);
+extern struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev);
+extern struct sysfs_device *sysfs_device_get_parent_with_subsystem(struct sysfs_device *dev, const char *subsystem);
+extern char *sysfs_attr_get_value(const char *devpath, const char *attr_name);
+extern int sysfs_resolve_link(char *path, size_t size);
+extern int sysfs_lookup_devpath_by_subsys_id(char *devpath, size_t len, const char *subsystem, const char *id);
+
+#endif