X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udev_sysfs.c;h=34ae9ac14fd400758d5d3a618dc527d19a9bbd54;hp=0e448894fef8f3c6edee1a0cd49cdd631f4d2893;hb=fcfeda1907035a3d3c7afc67ad38b032b87f36d9;hpb=82c60ce57206148d00e8d3a210a72a0e7f2aa380

diff --git a/udev_sysfs.c b/udev_sysfs.c
index 0e448894f..34ae9ac14 100644
--- a/udev_sysfs.c
+++ b/udev_sysfs.c
@@ -92,7 +92,6 @@ void sysfs_device_set_values(struct sysfs_device *dev, const char *devpath,
 	pos = strrchr(dev->devpath, '/');
 	if (pos == NULL)
 		return;
-
 	strlcpy(dev->kernel, &pos[1], sizeof(dev->kernel));
 	dbg("kernel='%s'", dev->kernel);
 
@@ -156,9 +155,21 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
 	int len;
 	char *pos;
 
+	/* we handle only these devpathes */
+	if (devpath != NULL &&
+	    strncmp(devpath, "/devices/", 9) != 0 &&
+	    strncmp(devpath, "/subsystem/", 11) != 0 &&
+	    strncmp(devpath, "/module/", 8) != 0 &&
+	    strncmp(devpath, "/bus/", 5) != 0 &&
+	    strncmp(devpath, "/class/", 7) != 0 &&
+	    strncmp(devpath, "/block/", 7) != 0)
+		return NULL;
+
 	dbg("open '%s'", devpath);
 	strlcpy(devpath_real, devpath, sizeof(devpath_real));
 	remove_trailing_chars(devpath_real, '/');
+	if (devpath[0] == '\0' )
+		return NULL;
 
 	/* look for device already in cache (we never put an untranslated path in the cache) */
 	list_for_each_entry(dev_loop, &dev_list, node) {
@@ -197,14 +208,26 @@ struct sysfs_device *sysfs_device_get(const char *devpath)
 
 	sysfs_device_set_values(dev, devpath_real, NULL, NULL);
 
-	/* get subsystem */
-	if (strncmp(dev->devpath, "/class/", 7) == 0) {
+	/* get subsystem name */
+	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) {
+		/* get subsystem from "subsystem" link */
+		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));
+	} else if (strncmp(dev->devpath, "/class/", 7) == 0) {
+		/* get subsystem from class dir */
 		strlcpy(dev->subsystem, &dev->devpath[7], sizeof(dev->subsystem));
 		pos = strchr(dev->subsystem, '/');
 		if (pos != NULL)
 			pos[0] = '\0';
 		else
-			dev->subsystem[0] = '\0';
+			strlcpy(dev->subsystem, "subsystem", sizeof(dev->subsystem));
 	} else if (strncmp(dev->devpath, "/block/", 7) == 0) {
 		strlcpy(dev->subsystem, "block", sizeof(dev->subsystem));
 	} else if (strncmp(dev->devpath, "/devices/", 9) == 0) {
@@ -219,36 +242,32 @@ 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));
-		strlcat(link_path, "/driver", sizeof(link_path));
-		len = readlink(link_path, link_target, sizeof(link_target));
-		if (len > 0) {
-			link_target[len] = '\0';
-			dbg("driver link '%s' points to '%s'", link_path, link_target);
-			pos = strrchr(link_target, '/');
-			if (pos != NULL)
-				strlcpy(dev->driver, &pos[1], sizeof(dev->driver));
 		}
-	} else if (strncmp(dev->devpath, "/bus/", 5) == 0 && strstr(dev->devpath, "/drivers/")) {
+	} else if (strstr(dev->devpath, "/drivers/") != NULL) {
 		strlcpy(dev->subsystem, "drivers", sizeof(dev->subsystem));
 	} else if (strncmp(dev->devpath, "/module/", 8) == 0) {
 		strlcpy(dev->subsystem, "module", sizeof(dev->subsystem));
+	} else if (strncmp(dev->devpath, "/subsystem/", 11) == 0) {
+		pos = strrchr(dev->devpath, '/');
+		if (pos == &dev->devpath[10])
+			strlcpy(dev->subsystem, "subsystem", sizeof(dev->subsystem));
+	} else if (strncmp(dev->devpath, "/bus/", 5) == 0) {
+		pos = strrchr(dev->devpath, '/');
+		if (pos == &dev->devpath[4])
+			strlcpy(dev->subsystem, "subsystem", sizeof(dev->subsystem));
+	}
+
+	/* get driver name */
+	strlcpy(link_path, sysfs_path, sizeof(link_path));
+	strlcat(link_path, dev->devpath, sizeof(link_path));
+	strlcat(link_path, "/driver", sizeof(link_path));
+	len = readlink(link_path, link_target, sizeof(link_target));
+	if (len > 0) {
+		link_target[len] = '\0';
+		dbg("driver link '%s' points to '%s'", link_path, link_target);
+		pos = strrchr(link_target, '/');
+		if (pos != NULL)
+			strlcpy(dev->driver, &pos[1], sizeof(dev->driver));
 	}
 
 	dbg("add to cache 'devpath=%s', subsystem='%s', driver='%s'", dev->devpath, dev->subsystem, dev->driver);
@@ -268,12 +287,6 @@ struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
 	if (dev->parent != NULL)
 		return dev->parent;
 
-	/* requesting a parent is only valid for devices */
-	if ((strncmp(dev->devpath, "/devices/", 9) != 0) &&
-	    (strncmp(dev->devpath, "/class/", 7) != 0) &&
-	    (strncmp(dev->devpath, "/block/", 7) != 0))
-		return NULL;
-
 	strlcpy(parent_devpath, dev->devpath, sizeof(parent_devpath));
 	dbg("'%s'", parent_devpath);
 
@@ -283,17 +296,6 @@ struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
 		return NULL;
 	pos[0] = '\0';
 
-	/* are we at the top level of /devices */
-	if (strcmp(parent_devpath, "/devices") == 0) {
-		dbg("/devices top level");
-		return NULL;
-	}
-
-	/* at the top level of class/block we want to follow the "device" link */
-	if (strcmp(parent_devpath, "/block") == 0) {
-		dbg("/block top level, look for device link");
-		goto device_link;
-	}
 	if (strncmp(parent_devpath, "/class", 6) == 0) {
 		pos = strrchr(parent_devpath, '/');
 		if (pos == &parent_devpath[6] || pos == parent_devpath) {
@@ -301,6 +303,16 @@ struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
 			goto device_link;
 		}
 	}
+	if (strcmp(parent_devpath, "/block") == 0) {
+		dbg("/block top level, look for device link");
+		goto device_link;
+	}
+
+	/* are we at the top level? */
+	pos = strrchr(parent_devpath, '/');
+	if (pos == NULL || pos == parent_devpath)
+		return NULL;
+
 	/* get parent and remember it */
 	dev->parent = sysfs_device_get(parent_devpath);
 	return dev->parent;
@@ -421,3 +433,94 @@ char *sysfs_attr_get_value(const char *devpath, const char *attr_name)
 out:
 	return attr->value;
 }
+
+int sysfs_lookup_devpath_by_subsys_id(char *devpath_full, size_t len, const char *subsystem, const char *id)
+{
+	size_t sysfs_len;
+	char path_full[PATH_SIZE];
+	char *path;
+	struct stat statbuf;
+
+	sysfs_len = strlcpy(path_full, sysfs_path, sizeof(path_full));
+	path = &path_full[sysfs_len];
+
+	if (strcmp(subsystem, "subsystem") == 0) {
+		strlcpy(path, "/subsystem/", sizeof(path_full) - sysfs_len);
+		strlcat(path, id, sizeof(path_full) - sysfs_len);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+
+		strlcpy(path, "/bus/", sizeof(path_full) - sysfs_len);
+		strlcat(path, id, sizeof(path_full) - sysfs_len);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+		goto out;
+
+		strlcpy(path, "/class/", sizeof(path_full) - sysfs_len);
+		strlcat(path, id, sizeof(path_full) - sysfs_len);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+	}
+
+	if (strcmp(subsystem, "module") == 0) {
+		strlcpy(path, "/module/", sizeof(path_full) - sysfs_len);
+		strlcat(path, id, sizeof(path_full) - sysfs_len);
+		if (stat(path_full, &statbuf) == 0)
+			goto found;
+		goto out;
+	}
+
+	if (strcmp(subsystem, "drivers") == 0) {
+		char subsys[NAME_SIZE];
+		char *driver;
+
+		strlcpy(subsys, id, sizeof(subsys));
+		driver = strchr(subsys, ':');
+		if (driver != NULL) {
+			driver[0] = '\0';
+			driver = &driver[1];
+			strlcpy(path, "/subsystem/", sizeof(path_full) - sysfs_len);
+			strlcat(path, subsys, sizeof(path_full) - sysfs_len);
+			strlcat(path, "/drivers/", sizeof(path_full) - sysfs_len);
+			strlcat(path, driver, sizeof(path_full) - sysfs_len);
+			if (stat(path_full, &statbuf) == 0)
+				goto found;
+
+			strlcpy(path, "/bus/", sizeof(path_full) - sysfs_len);
+			strlcat(path, subsys, sizeof(path_full) - sysfs_len);
+			strlcat(path, "/drivers/", sizeof(path_full) - sysfs_len);
+			strlcat(path, driver, sizeof(path_full) - sysfs_len);
+			if (stat(path_full, &statbuf) == 0)
+				goto found;
+		}
+		goto out;
+	}
+
+	strlcpy(path, "/subsystem/", sizeof(path_full) - sysfs_len);
+	strlcat(path, subsystem, sizeof(path_full) - sysfs_len);
+	strlcat(path, "/devices/", sizeof(path_full) - sysfs_len);
+	strlcat(path, id, sizeof(path_full) - sysfs_len);
+	if (stat(path_full, &statbuf) == 0)
+		goto found;
+
+	strlcpy(path, "/bus/", sizeof(path_full) - sysfs_len);
+	strlcat(path, subsystem, sizeof(path_full) - sysfs_len);
+	strlcat(path, "/devices/", sizeof(path_full) - sysfs_len);
+	strlcat(path, id, sizeof(path_full) - sysfs_len);
+	if (stat(path_full, &statbuf) == 0)
+		goto found;
+
+	strlcpy(path, "/class/", sizeof(path_full) - sysfs_len);
+	strlcat(path, subsystem, sizeof(path_full) - sysfs_len);
+	strlcat(path, "/", sizeof(path_full) - sysfs_len);
+	strlcat(path, id, sizeof(path_full) - sysfs_len);
+	if (stat(path_full, &statbuf) == 0)
+		goto found;
+out:
+	return 0;
+found:
+	if (S_ISLNK(statbuf.st_mode))
+		sysfs_resolve_link(path, sizeof(path_full) - sysfs_len);
+	strlcpy(devpath_full, path, len);
+	return 1;
+}