X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udev_sysfs.c;h=8de523dadf66abc3bbf0198c9dac01036ca7f608;hp=19fd614e633a5a3204dfd819775e0185e31305c5;hb=7d1e179f86aabeb5c206bf9b5bcac52235a9afbf;hpb=1aa1e24848903d11780db1ade355be73ad61a937

diff --git a/udev_sysfs.c b/udev_sysfs.c
index 19fd614e6..8de523dad 100644
--- a/udev_sysfs.c
+++ b/udev_sysfs.c
@@ -26,6 +26,7 @@
 #include <fcntl.h>
 #include <ctype.h>
 #include <errno.h>
+#include <sys/stat.h>
 
 #include "udev.h"
 
@@ -128,7 +129,7 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
 	strlcpy(path, sysfs_path, sizeof(path));
 	strlcat(path, devpath_real, sizeof(path));
 	if (lstat(path, &statbuf) != 0) {
-		dbg("stat '%s' failed: %s", devpath, strerror(errno));
+		dbg("stat '%s' failed: %s", path, strerror(errno));
 		return NULL;
 	}
 
@@ -182,10 +183,10 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
 			pos[0] = '\0';
 		else
 			dev->subsystem[0] = '\0';
-	} else if (strncmp(devpath, "/block/", 7) == 0) {
+	} else if (strncmp(dev->devpath, "/block/", 7) == 0) {
 		strlcpy(dev->subsystem, "block", sizeof(dev->subsystem));
-	} else if (strncmp(devpath, "/devices/", 9) == 0) {
-		/* get subsystem from bus name */
+	} else if (strncmp(dev->devpath, "/devices/", 9) == 0) {
+		/* get subsystem from "bus" link */
 		strlcpy(link_path, sysfs_path, sizeof(link_path));
 		strlcat(link_path, dev->devpath, sizeof(link_path));
 		strlcat(link_path, "/bus", sizeof(link_path));
@@ -196,8 +197,20 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
 			pos = strrchr(link_target, '/');
 			if (pos != NULL)
 				strlcpy(dev->subsystem, &pos[1], sizeof(dev->subsystem));
+		} else {
+			/* get subsystem from "subsystem" link */
+			strlcpy(link_path, sysfs_path, sizeof(link_path));
+			strlcat(link_path, dev->devpath, sizeof(link_path));
+			strlcat(link_path, "/subsystem", sizeof(link_path));
+			len = readlink(link_path, link_target, sizeof(link_target));
+			if (len > 0) {
+				link_target[len] = '\0';
+				dbg("subsystem link '%s' points to '%s'", link_path, link_target);
+				pos = strrchr(link_target, '/');
+				if (pos != NULL)
+					strlcpy(dev->subsystem, &pos[1], sizeof(dev->subsystem));
+			}
 		}
-
 		/* get driver name */
 		strlcpy(link_path, sysfs_path, sizeof(link_path));
 		strlcat(link_path, dev->devpath, sizeof(link_path));
@@ -210,9 +223,9 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
 			if (pos != NULL)
 				strlcpy(dev->driver, &pos[1], sizeof(dev->driver));
 		}
-	} else if (strncmp(devpath, "/bus/", 5) == 0 && strstr(devpath, "/drivers/")) {
+	} else if (strncmp(dev->devpath, "/bus/", 5) == 0 && strstr(dev->devpath, "/drivers/")) {
 		strlcpy(dev->subsystem, "drivers", sizeof(dev->subsystem));
-	} else if (strncmp(devpath, "/module/", 8) == 0) {
+	} else if (strncmp(dev->devpath, "/module/", 8) == 0) {
 		strlcpy(dev->subsystem, "module", sizeof(dev->subsystem));
 	}
 
@@ -262,7 +275,7 @@ struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
 	if (strncmp(parent_devpath, "/class", 6) == 0) {
 		pos = strrchr(parent_devpath, '/');
 		if (pos == &parent_devpath[6] || pos == parent_devpath) {
-			dbg("class top level, look for device link");
+			dbg("/class top level, look for device link");
 			goto device_link;
 		}
 	}
@@ -294,6 +307,19 @@ device_link:
 	return sysfs_device_get(parent_devpath);
 }
 
+struct sysfs_device *sysfs_device_get_parent_with_subsystem(struct sysfs_device *dev, const char *subsystem)
+{
+	struct sysfs_device *dev_parent;
+
+	dev_parent = sysfs_device_get_parent(dev);
+	while (dev_parent != NULL) {
+		if (strcmp(dev_parent->subsystem, subsystem) == 0)
+			return dev_parent;
+		dev_parent = sysfs_device_get_parent(dev_parent);
+	}
+	return NULL;
+}
+
 char *sysfs_attr_get_value(const char *devpath, const char *attr_name)
 {
 	char path_full[PATH_SIZE];