X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=util-linux%2Fmdev.c;h=a4c0520ac302179d7ee58a77de0b68b8f8a2cc9e;hb=67075bb95f23233c49628a624cc6ba86c3462dcb;hp=5e1cd36bb72bbfae11d8cc1c06b9415cd0f55776;hpb=32dcc53b7162406148203b8222c3f5c5056f70f2;p=oweals%2Fbusybox.git

diff --git a/util-linux/mdev.c b/util-linux/mdev.c
index 5e1cd36bb..a4c0520ac 100644
--- a/util-linux/mdev.c
+++ b/util-linux/mdev.c
@@ -19,7 +19,8 @@ struct globals {
 #define root_major (G.root_major)
 #define root_minor (G.root_minor)
 
-#define MAX_SYSFS_DEPTH 3 /* prevent infinite loops in /sys symlinks */
+/* Prevent infinite loops in /sys symlinks */
+#define MAX_SYSFS_DEPTH 3
 
 /* We use additional 64+ bytes in make_device() */
 #define SCRATCH_SIZE 80
@@ -46,6 +47,7 @@ static void make_device(char *path, int delete)
 	char *dev_maj_min = path + strlen(path);
 	char *command = NULL;
 	char *alias = NULL;
+	char aliaslink = aliaslink; /* for compiler */
 
 	/* Force the configuration file settings exactly. */
 	umask(0);
@@ -70,8 +72,14 @@ static void make_device(char *path, int delete)
 	/* Determine device name, type, major and minor */
 	device_name = bb_basename(path);
 	/* http://kernel.org/doc/pending/hotplug.txt says that only
-	 * "/sys/block/..." is for block devices. "sys/bus" etc is not! */
-	type = (strncmp(&path[5], "block/", 6) == 0 ? S_IFBLK : S_IFCHR);
+	 * "/sys/block/..." is for block devices. "/sys/bus" etc is not!
+	 * Since kernel 2.6.25 block devices are also in /sys/class/block. */
+	/* TODO: would it be acceptable to just use strstr(path, "/block/")? */
+	if (strncmp(&path[5], "class/block/"+6, 6) != 0
+	 && strncmp(&path[5], "class/block/", 12) != 0)
+	        type = S_IFCHR;
+	else
+	        type = S_IFBLK;
 
 	if (ENABLE_FEATURE_MDEV_CONF) {
 		FILE *fp;
@@ -114,8 +122,11 @@ static void make_device(char *path, int delete)
 
 				/* If not this device, skip rest of line */
 				/* (regexec returns whole pattern as "range" 0) */
-				if (result || off[0].rm_so || off[0].rm_eo != strlen(device_name))
+				if (result || off[0].rm_so
+				 || ((int)off[0].rm_eo != (int)strlen(device_name))
+				) {
 					goto next_line;
+				}
 			}
 
 			/* This line matches: stop parsing the file
@@ -159,18 +170,20 @@ static void make_device(char *path, int delete)
 #if ENABLE_FEATURE_MDEV_RENAME
 			if (!next)
 				break;
-			if (*next == '>') {
+			if (*next == '>' || *next == '=') {
 #if ENABLE_FEATURE_MDEV_RENAME_REGEXP
 				char *s, *p;
 				unsigned i, n;
 
+				aliaslink = *next;
 				val = next;
 				next = next_field(val);
 				/* substitute %1..9 with off[1..9], if any */
 				n = 0;
 				s = val;
-				while (*s && *s++ == '%')
-					n++;
+				while (*s)
+					if (*s++ == '%')
+						n++;
 
 				p = alias = xzalloc(strlen(val) + n * strlen(device_name));
 				s = val + 1;
@@ -189,6 +202,7 @@ static void make_device(char *path, int delete)
 					s++;
 				}
 #else
+				aliaslink = *next;
 				val = next;
 				next = next_field(val);
 				alias = xstrdup(val + 1);
@@ -259,10 +273,10 @@ static void make_device(char *path, int delete)
 					}
 				}
 
-				/* recreate device_name as a symlink to moved device node */
-				if (rename(device_name, alias) == 0) {
+				/* move the device, and optionally
+				 * make a symlink to moved device node */
+				if (rename(device_name, alias) == 0 && aliaslink == '>')
 					symlink(alias, device_name);
-				}
 
 				free(alias);
 			}
@@ -286,10 +300,10 @@ static void make_device(char *path, int delete)
 }
 
 /* File callback for /sys/ traversal */
-static int fileAction(const char *fileName,
-                      struct stat *statbuf ATTRIBUTE_UNUSED,
-                      void *userData,
-                      int depth ATTRIBUTE_UNUSED)
+static int FAST_FUNC fileAction(const char *fileName,
+		struct stat *statbuf UNUSED_PARAM,
+		void *userData,
+		int depth UNUSED_PARAM)
 {
 	size_t len = strlen(fileName) - 4; /* can't underflow */
 	char *scratch = userData;
@@ -306,10 +320,10 @@ static int fileAction(const char *fileName,
 }
 
 /* Directory callback for /sys/ traversal */
-static int dirAction(const char *fileName ATTRIBUTE_UNUSED,
-                      struct stat *statbuf ATTRIBUTE_UNUSED,
-                      void *userData ATTRIBUTE_UNUSED,
-                      int depth)
+static int FAST_FUNC dirAction(const char *fileName UNUSED_PARAM,
+		struct stat *statbuf UNUSED_PARAM,
+		void *userData UNUSED_PARAM,
+		int depth)
 {
 	return (depth >= MAX_SYSFS_DEPTH ? SKIP : TRUE);
 }
@@ -379,6 +393,21 @@ int mdev_main(int argc, char **argv)
 	char *env_path;
 	RESERVE_CONFIG_BUFFER(temp, PATH_MAX + SCRATCH_SIZE);
 
+	/* We can be called as hotplug helper */
+	/* Kernel cannot provide suitable stdio fds for us, do it ourself */
+#if 1
+	bb_sanitize_stdio();
+#else
+	/* Debug code */
+	/* Replace LOGFILE by other file or device name if you need */
+#define LOGFILE "/dev/console"
+	/* Just making sure fd 0 is not closed,
+	 * we don't really intend to read from it */
+	xmove_fd(xopen("/", O_RDONLY), STDIN_FILENO);
+	xmove_fd(xopen(LOGFILE, O_WRONLY|O_APPEND), STDOUT_FILENO);
+	xmove_fd(xopen(LOGFILE, O_WRONLY|O_APPEND), STDERR_FILENO);
+#endif
+
 	xchdir("/dev");
 
 	if (argc == 2 && !strcmp(argv[1], "-s")) {
@@ -391,14 +420,17 @@ int mdev_main(int argc, char **argv)
 		root_major = major(st.st_dev);
 		root_minor = minor(st.st_dev);
 
+		/* ACTION_FOLLOWLINKS is needed since in newer kernels
+		 * /sys/block/loop* (for example) are symlinks to dirs,
+		 * not real directories.
+		 * (kernel's CONFIG_SYSFS_DEPRECATED makes them real dirs,
+		 * but we can't enforce that on users) */
 		recursive_action("/sys/block",
 			ACTION_RECURSE | ACTION_FOLLOWLINKS,
 			fileAction, dirAction, temp, 0);
-
 		recursive_action("/sys/class",
 			ACTION_RECURSE | ACTION_FOLLOWLINKS,
 			fileAction, dirAction, temp, 0);
-
 	} else {
 		/* Hotplug:
 		 * env ACTION=... DEVPATH=... mdev