X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;ds=sidebyside;f=udev%2Fudev-watch.c;h=e2c096af0f4d0f3459f57805815894c9c7d4c564;hb=977f6f4b3dfbdd32d7df5a774a4ed761d5d4b98f;hp=92ab90785602db9d63dd93f147ddcce9391e58b1;hpb=4aca304e48d69766d47439f0d3dcaa8797b46c78;p=elogind.git

diff --git a/udev/udev-watch.c b/udev/udev-watch.c
index 92ab90785..e2c096af0 100644
--- a/udev/udev-watch.c
+++ b/udev/udev-watch.c
@@ -1,6 +1,7 @@
 /*
  * Copyright (C) 2004-2008 Kay Sievers <kay.sievers@vrfy.org>
  * Copyright (C) 2009 Canonical Ltd.
+ * Copyright (C) 2009 Scott James Remnant <scott@netsplit.com>
  *
  * 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
@@ -84,6 +85,7 @@ void udev_watch_restore(struct udev *udev)
 		while ((ent = readdir(dir)) != NULL) {
 			char path[UTIL_PATH_SIZE];
 			char buf[UTIL_PATH_SIZE];
+			ssize_t syslen;
 			ssize_t len;
 			struct udev_device *dev;
 
@@ -94,13 +96,13 @@ void udev_watch_restore(struct udev *udev)
 			util_strlcat(path, "/", sizeof(path));
 			util_strlcat(path, ent->d_name, sizeof(path));
 
-			len = readlink(path, buf, sizeof(buf));
-			if (len <= 0) {
+			syslen = util_strlcpy(buf, udev_get_sys_path(udev), sizeof(buf));
+			len = readlink(path, &buf[syslen], sizeof(buf)-syslen);
+			if (len <= 0 || len >= (ssize_t)(sizeof(buf)-syslen)) {
 				unlink(path);
 				continue;
 			}
-
-			buf[len] = '\0';
+			buf[syslen + len] = '\0';
 			dbg(udev, "old watch to '%s' found\n", buf);
 			dev = udev_device_new_from_syspath(udev, buf);
 			if (dev == NULL) {
@@ -123,108 +125,66 @@ void udev_watch_restore(struct udev *udev)
 	}
 }
 
-static const char *udev_watch_filename(struct udev *udev, int wd)
-{
-	static char filename[UTIL_PATH_SIZE];
-	char str[32];
-
-	sprintf(str, "%d", wd);
-	util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
-	util_strlcat(filename, "/.udev/watch/", sizeof(filename));
-	util_strlcat(filename, str, sizeof(filename));
-
-	return filename;
-}
-
 void udev_watch_begin(struct udev *udev, struct udev_device *dev)
 {
-	const char *filename;
+	char filename[UTIL_PATH_SIZE];
 	int wd;
 
 	if (inotify_fd < 0)
 		return;
 
+	info(udev, "adding watch on '%s'\n", udev_device_get_devnode(dev));
 	wd = inotify_add_watch(inotify_fd, udev_device_get_devnode(dev), IN_CLOSE_WRITE);
 	if (wd < 0) {
 		err(udev, "inotify_add_watch(%d, %s, %o) failed: %m\n",
 		    inotify_fd, udev_device_get_devnode(dev), IN_CLOSE_WRITE);
 	}
 
-	filename = udev_watch_filename(udev, wd);
+	snprintf(filename, sizeof(filename), "%s/.udev/watch/%d", udev_get_dev_path(udev), wd);
 	util_create_path(udev, filename);
 	unlink(filename);
-	symlink(udev_device_get_syspath(dev), filename);
+	symlink(udev_device_get_devpath(dev), filename);
+
+	udev_device_set_watch_handle(dev, wd);
 }
 
-void udev_watch_clear(struct udev *udev, struct udev_device *dev)
+void udev_watch_end(struct udev *udev, struct udev_device *dev)
 {
-	static char filename[UTIL_PATH_SIZE];
-	DIR *dir;
-	struct dirent *ent;
-
-	util_strlcpy(filename, udev_get_dev_path(udev), sizeof(filename));
-	util_strlcat(filename, "/.udev/watch", sizeof(filename));
+	int wd;
+	char filename[UTIL_PATH_SIZE];
 
-	dir = opendir(filename);
-	if (dir == NULL)
+	if (inotify_fd < 0)
 		return;
 
-	while ((ent = readdir(dir)) != NULL) {
-		char path[UTIL_PATH_SIZE];
-		char buf[UTIL_PATH_SIZE];
-		ssize_t len;
-
-		if (ent->d_name[0] < '0' || ent->d_name[0] > '9')
-			continue;
-
-		util_strlcpy(path, filename, sizeof(path));
-		util_strlcat(path, "/", sizeof(path));
-		util_strlcat(path, ent->d_name, sizeof(path));
-
-		len = readlink(path, buf, sizeof(buf));
-		if (len <= 0)
-			continue;
-
-		buf[len] = '\0';
-		if (strcmp(buf, udev_device_get_syspath(dev)))
-			continue;
-
-		/* this is the watch we're looking for */
-		info(udev, "clearing existing watch on '%s'\n", udev_device_get_devnode(dev));
-		udev_watch_end(udev, atoi(ent->d_name));
-	}
-
-	closedir(dir);
-}
-
-void udev_watch_end(struct udev *udev, int wd)
-{
-	const char *filename;
-
-	if (inotify_fd < 0 || wd < 0)
+	wd = udev_device_get_watch_handle(dev);
+	if (wd < 0)
 		return;
 
+	info(udev, "removing watch on '%s'\n", udev_device_get_devnode(dev));
 	inotify_rm_watch(inotify_fd, wd);
 
-	filename = udev_watch_filename(udev, wd);
+	snprintf(filename, sizeof(filename), "%s/.udev/watch/%d", udev_get_dev_path(udev), wd);
 	unlink(filename);
+
+	udev_device_set_watch_handle(dev, -1);
 }
 
-const char *udev_watch_lookup(struct udev *udev, int wd)
+struct udev_device *udev_watch_lookup(struct udev *udev, int wd)
 {
-	const char *filename;
-	static char buf[UTIL_PATH_SIZE];
+	char filename[UTIL_PATH_SIZE];
+	char buf[UTIL_PATH_SIZE];
+	ssize_t syslen;
 	ssize_t len;
 
 	if (inotify_fd < 0 || wd < 0)
 		return NULL;
 
-	filename = udev_watch_filename(udev, wd);
-	len = readlink(filename, buf, sizeof(buf));
-	if (len > 0) {
-		buf[len] = '\0';
-
-		return buf;
+	snprintf(filename, sizeof(filename), "%s/.udev/watch/%d", udev_get_dev_path(udev), wd);
+	syslen = util_strlcpy(buf, udev_get_sys_path(udev), sizeof(buf));
+	len = readlink(filename, &buf[syslen], sizeof(buf)-syslen);
+	if (len > 0 || len < (ssize_t)(sizeof(buf)-syslen)) {
+		buf[syslen + len] = '\0';
+		return udev_device_new_from_syspath(udev, buf);
 	}
 
 	return NULL;