New applet, devfsd, by Matteo Croce and Tito

6 files changed, 2070 insertions, 0 deletions

diff --git a/AUTHORS b/AUTHORS
index 2c26e0b44..e2e20478f 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -119,3 +119,7 @@ Charles P. Wright <cpwright@villagenet.com>
 
 Enrique Zanardi <ezanardi@ull.es>
     tarcat (since removed), loadkmap, various fixes, Debian maintenance
+
+Tito Ragusa <farmatito@tiscali.it>
+	devfsd and size optimizations in strings, openvt and deallocvt.
+
diff --git a/include/applets.h b/include/applets.h
index b1425fa81..6f1295a30 100644
--- a/include/applets.h
+++ b/include/applets.h
@@ -142,6 +142,9 @@
 #ifdef CONFIG_DELUSER
 	APPLET(deluser, deluser_main, _BB_DIR_BIN, _BB_SUID_NEVER)
 #endif
+#ifdef CONFIG_DEVFSD
+	APPLET(devfsd, devfsd_main, _BB_DIR_SBIN, _BB_SUID_NEVER)
+#endif
 #ifdef CONFIG_DF
 	APPLET(df, df_main, _BB_DIR_BIN, _BB_SUID_NEVER)
 #endif
diff --git a/include/usage.h b/include/usage.h
index c109d0cf6..0b03102a7 100644
--- a/include/usage.h
+++ b/include/usage.h
@@ -336,6 +336,18 @@
 #define deluser_full_usage \
 	 "Deletes user USER from the system"
 
+#define devfsd_trivial_usage \
+	"mntpnt [-v] [-fg] [-np]"
+#define devfsd_full_usage \
+	"Optional daemon for managing devfs (the Linux Device Filesystem).\n" \
+	"\nOptions:\n" \
+	"\tmntpnt\tThe mount point where devfs is mounted.\n\n" \
+	"\t-v\tPrint the protocol version numbers for devfsd\n" \
+	"\t\tand the kernel-side protocol version and exits.\n" \
+	"\t-fg\tRun the daemon in the foreground.\n\n" \
+	"\t-np\tExit  after  parsing  the configuration file and processing syn-\n" \
+	"\t\tthetic REGISTER events. Do not poll for events." 
+
 #ifdef CONFIG_FEATURE_HUMAN_READABLE
   #define USAGE_HUMAN_READABLE(a) a
   #define USAGE_NOT_HUMAN_READABLE(a)
diff --git a/miscutils/Config.in b/miscutils/Config.in
index 701af9c2d..fa6ea7f68 100644
--- a/miscutils/Config.in
+++ b/miscutils/Config.in
@@ -40,6 +40,27 @@ config CONFIG_DC
 	  Dc is a reverse-polish desk calculator which supports unlimited
 	  precision arithmetic.
 
+config CONFIG_DEVFSD
+	bool "devfsd"
+	default n
+	help
+	  Provides compatibility with old device names on a devfs systems.
+	  You should set it to true if you have devfs enabled.
+
+config CONFIG_DEVFSD_VERBOSE
+	bool "Increases logging to stderr and syslog"
+	default n
+	depends on CONFIG_DEVFSD
+	help
+	  Increases logging to stderr and syslog.
+
+config CONFIG_DEVFSD_DEBUG
+	bool "Adds function names to program output"
+	default n
+	depends on CONFIG_DEVFSD
+	help
+	  Adds function names to program output.
+
 config CONFIG_LAST
 	bool "last"
 	default n
diff --git a/miscutils/Makefile.in b/miscutils/Makefile.in
index 66370f015..892f7d196 100644
--- a/miscutils/Makefile.in
+++ b/miscutils/Makefile.in
@@ -28,6 +28,7 @@ MISCUTILS-$(CONFIG_ADJTIMEX)		+= adjtimex.o
 MISCUTILS-$(CONFIG_CROND)               += crond.o
 MISCUTILS-$(CONFIG_CRONTAB)             += crontab.o
 MISCUTILS-$(CONFIG_DC)			+= dc.o
+MISCUTILS-$(CONFIG_DEVFSD)		+= devfsd.o
 MISCUTILS-$(CONFIG_HDPARM)		+= hdparm.o
 MISCUTILS-$(CONFIG_LAST)		+= last.o
 MISCUTILS-$(CONFIG_MAKEDEVS)		+= makedevs.o
diff --git a/miscutils/devfsd.c b/miscutils/devfsd.c
new file mode 100644
index 000000000..4391f341d
--- /dev/null
+++ b/miscutils/devfsd.c
@@ -0,0 +1,2029 @@
+/*
+	devfsd implementation for busybox
+
+	Copyright (C) 2003 by Tito Ragusa <farmatito@tiscali.it>
+
+	Busybox version is based on some previous work and ideas
+	Copyright (C) [2003] by [Matteo Croce] <3297627799@wind.it>
+
+	devfsd.c
+
+	Main file for  devfsd  (devfs daemon for Linux).
+
+    Copyright (C) 1998-2002  Richard Gooch
+
+	devfsd.h
+
+    Header file for  devfsd  (devfs daemon for Linux).
+
+    Copyright (C) 1998-2000  Richard Gooch
+
+	compat_name.c
+
+    Compatibility name file for  devfsd  (build compatibility names).
+
+    Copyright (C) 1998-2002  Richard Gooch
+
+	expression.c
+
+    This code provides Borne Shell-like expression expansion.
+
+    Copyright (C) 1997-1999  Richard Gooch
+
+	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; either version 2 of the License, or
+    (at your option) any later version.
+
+    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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+    Richard Gooch may be reached by email at  rgooch@atnf.csiro.au
+    The postal address is:
+      Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia.
+*/
+
+#include "libbb.h"
+#include "busybox.h"
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+#include <ctype.h>
+#include <pwd.h>
+#include <grp.h>
+#include <sys/time.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <linux/major.h>
+#include <linux/devfs_fs.h>
+#include <linux/kdev_t.h>
+#include <syslog.h>
+#include <signal.h>
+#include <regex.h>
+#include <errno.h>
+
+#ifndef IDE6_MAJOR        /*  In case we're building with an ancient kernel  */
+#  define IDE6_MAJOR      88
+#  define IDE7_MAJOR      89
+#  define IDE8_MAJOR      90
+#  define IDE9_MAJOR      91
+#endif
+
+/* These are now in Config.in */
+/* define this if you want to have more output on stderr and syslog at the same time */
+/*#define CONFIG_DEVFSD_VERBOSE*/
+/* define this if you want to have the function names in output */
+/*#define CONFIG_DEVFSD_DEBUG*/
+
+#define BUFFER_SIZE 16384
+#define DEVFSD_VERSION "1.3.25"
+#define CONFIG_FILE  "/etc/devfsd.conf"
+#define MAX_ARGS     (6 + 1)
+#define MAX_SUBEXPR  10
+#define STRING_LENGTH 255
+
+/* for get_uid_gid() */
+#define UID			0
+#define GID			1
+
+/* 	for msg_logger(), do_ioctl(),
+	fork_and_execute() and xopendir(). */
+# define DIE				1
+# define NO_DIE			0
+
+/*  Update only after changing code to reflect new protocol  */
+#define DEVFSD_PROTOCOL_REVISION_DAEMON  5
+
+/*  Compile-time check  */
+#if DEVFSD_PROTOCOL_REVISION_KERNEL != DEVFSD_PROTOCOL_REVISION_DAEMON
+#error protocol version mismatch. Update your kernel headers
+#endif
+
+#define AC_PERMISSIONS				0
+#define AC_MODLOAD					1	/* not supported by busybox */
+#define AC_EXECUTE					2
+#define AC_MFUNCTION				3	/* not supported by busybox */
+#define AC_CFUNCTION				4	/* not supported by busybox */
+#define AC_COPY					5
+#define AC_IGNORE					6
+#define AC_MKOLDCOMPAT				7
+#define AC_MKNEWCOMPAT				8
+#define AC_RMOLDCOMPAT				9
+#define AC_RMNEWCOMPAT				10
+#define AC_RESTORE					11
+
+
+struct permissions_type
+{
+    mode_t mode;
+    uid_t uid;
+    gid_t gid;
+};
+
+struct execute_type
+{
+    char *argv[MAX_ARGS + 1];  /*  argv[0] must always be the programme  */
+};
+
+struct copy_type
+{
+    const char *source;
+    const char *destination;
+};
+
+struct action_type
+{
+    unsigned int what;
+    unsigned int when;
+};
+
+struct config_entry_struct
+{
+    struct action_type action;
+    regex_t preg;
+    union
+    {
+	struct permissions_type permissions;
+	struct execute_type execute;
+	struct copy_type copy;
+    }
+    u;
+    struct config_entry_struct *next;
+};
+
+struct get_variable_info
+{
+    const struct devfsd_notify_struct *info;
+    const char *devname;
+    char devpath[STRING_LENGTH];
+};
+
+static int st_expr_expand(char *, unsigned, const char *, const char *(*) (const char *, void *), void *);
+static const char *get_old_name(const char *, unsigned, char *, unsigned, unsigned);
+static int mksymlink (const char *oldpath, const char *newpath);
+static void read_config_file (const char *path, int optional, unsigned long *event_mask);
+static void process_config_line (const char *, unsigned long *);
+static int  do_servicing (int, unsigned long);
+static void service_name (const struct devfsd_notify_struct *);
+static void action_permissions (const struct devfsd_notify_struct *, const struct config_entry_struct *);
+static void action_execute (const struct devfsd_notify_struct *, const struct config_entry_struct *,
+							const regmatch_t *, unsigned);
+static void action_copy (const struct devfsd_notify_struct *, const struct config_entry_struct *,
+						 const regmatch_t *, unsigned);
+static void action_compat (const struct devfsd_notify_struct *, unsigned);
+static void free_config (void);
+static void do_restore (const char *, int);
+static int copy_inode (const char *, const struct stat *, mode_t, const char *, const struct stat *);
+static mode_t get_mode (const char *);
+static void signal_handler (int);
+static const char *get_variable (const char *, void *);
+static void do_scan_and_service (const char *);
+static int make_dir_tree (const char *);
+static int expand_expression(char *, unsigned, const char *, const char *(*)(const char *, void *), void *,
+							 const char *, const regmatch_t *, unsigned );
+static void expand_regexp (char *, size_t, const char *, const char *, const regmatch_t *, unsigned );
+static const char *expand_variable(	char *, unsigned, unsigned *, const char *,
+									const char *(*) (const char *, void *), void * );
+static const char *get_variable_v2(const char *, const char *(*) (const char *, void *), void *);
+static char get_old_ide_name (unsigned , unsigned);
+static char *write_old_sd_name (char *, unsigned, unsigned, char *);
+
+/* busybox functions */
+static void msg_logger(int die, int pri, const char * fmt, ... );
+static void do_ioctl(int die, int fd, int request, unsigned long event_mask_flag);
+static void fork_and_execute(int die, char *arg0, char **arg );
+DIR * xopendir(int die, const char * dir_name);
+static int get_uid_gid ( int, const char *);
+static void safe_memcpy( char * dest, const char * src, int len);
+
+/* Structs and vars */
+static struct config_entry_struct *first_config = NULL;
+static struct config_entry_struct *last_config = NULL;
+static const char *mount_point = NULL;
+static volatile int caught_signal = FALSE;
+static volatile int caught_sighup = FALSE;
+static struct initial_symlink_struct
+{
+    char *dest;
+    char *name;
+} initial_symlinks[] =
+{
+    {"/proc/self/fd", "fd"},
+    {"fd/0", "stdin"},
+    {"fd/1", "stdout"},
+    {"fd/2", "stderr"},
+    {NULL, NULL},
+};
+
+static struct event_type
+{
+    unsigned int type;        /*  The DEVFSD_NOTIFY_* value                  */
+    const char *config_name;  /*  The name used in the config file           */
+} event_types[] =
+{
+    {DEVFSD_NOTIFY_REGISTERED,   "REGISTER"},
+    {DEVFSD_NOTIFY_UNREGISTERED, "UNREGISTER"},
+    {DEVFSD_NOTIFY_ASYNC_OPEN,   "ASYNC_OPEN"},
+    {DEVFSD_NOTIFY_CLOSE,        "CLOSE"},
+    {DEVFSD_NOTIFY_LOOKUP,       "LOOKUP"},
+    {DEVFSD_NOTIFY_CHANGE,       "CHANGE"},
+    {DEVFSD_NOTIFY_CREATE,       "CREATE"},
+    {DEVFSD_NOTIFY_DELETE,       "DELETE"},
+    {0xffffffff,                 NULL}
+};
+
+/* busybox functions and messages */
+
+extern void xregcomp(regex_t * preg, const char *regex, int cflags);
+
+const char * const bb_msg_bad_config   		= "bad %s config file: %s\n";
+const char * const bb_msg_proto_rev			= "protocol revision";
+#ifdef CONFIG_DEVFSD_VERBOSE
+const char * const bb_msg_small_buffer		= "buffer too small\n";
+const char * const bb_msg_variable_not_found= "variable: %s not found\n";
+#endif
+
+static void msg_logger(int die, int pri, const char * fmt, ... )
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	if (access ("/dev/log", F_OK) == 0)
+	{
+		openlog(bb_applet_name, 0, LOG_DAEMON);
+		vsyslog( pri , fmt , ap);
+		closelog();
+ 	}
+#ifndef CONFIG_DEVFSD_VERBOSE
+	else
+#endif
+		bb_verror_msg(fmt, ap);
+	va_end(ap);
+	if(die==DIE)
+		exit(EXIT_FAILURE);
+}
+
+
+static void do_ioctl(int die, int fd, int request, unsigned long event_mask_flag)
+{
+	if (ioctl (fd, request, event_mask_flag) != 0)
+		msg_logger(die, LOG_ERR, "ioctl() failed: %m\n");
+}
+
+static void fork_and_execute(int die, char *arg0, char **arg )
+{
+	switch ( fork () )
+	{
+	case 0:
+		/*  Child  */
+		break;
+	case -1:
+		/*  Parent: Error  : die or return */
+		msg_logger(die, LOG_ERR,(char *) bb_msg_memory_exhausted);
+		return;
+	default:
+		/*  Parent : ok : return or exit  */
+		if(arg0 != NULL)
+		{
+			wait (NULL);
+			return;
+		}
+		exit (EXIT_SUCCESS);
+	}
+	 /* Child : if arg0 != NULL do execvp */
+	if(arg0 != NULL )
+	{
+		execvp (arg0, arg);
+		msg_logger(DIE, LOG_ERR, "execvp() failed: %s: %m\n", arg0);
+	}
+}
+
+
+DIR * xopendir(int die, const char * dir_name)
+{
+	DIR *dp;
+
+	if ( ( dp = opendir (dir_name) ) == NULL )
+ 		msg_logger( die, LOG_ERR, "opendir() failed: %s: %m\n", dir_name);
+	/* if die == DIE not reached else return NULL */
+	return dp;
+}
+
+static void safe_memcpy( char *dest, const char *src, int len)
+{
+	memcpy (dest , src , len );
+	dest[len] = '\0';
+}
+
+/*  Public functions follow  */
+
+int devfsd_main (int argc, char **argv)
+{
+	int print_version = FALSE;
+	int do_daemon = TRUE;
+	int no_polling = FALSE;
+	int fd, proto_rev, count;
+	unsigned long event_mask = 0;
+	struct sigaction new_action;
+	struct initial_symlink_struct *curr;
+
+	if (argc < 2)
+		bb_show_usage();
+
+	for (count = 2; count < argc; ++count)
+	{
+		if (strcmp (argv[count], "-v") == 0)
+			print_version = TRUE;
+		else if (strcmp (argv[count], "-fg") == 0)
+			do_daemon = FALSE;
+		else if (strcmp (argv[count], "-np") == 0)
+			no_polling = TRUE;
+		else
+			bb_show_usage();
+	}
+
+	mount_point = argv[1];
+
+	if (chdir (mount_point) != 0)
+		bb_error_msg_and_die( " %s: %m", mount_point);
+
+	fd = bb_xopen (".devfsd", O_RDONLY);
+
+	if (fcntl (fd, F_SETFD, FD_CLOEXEC) != 0)
+		bb_error_msg( "FD_CLOEXEC");
+
+	do_ioctl(DIE, fd, DEVFSDIOC_GET_PROTO_REV,(int )&proto_rev);
+
+	/*setup initial entries */
+    for (curr = initial_symlinks; curr->dest != NULL; ++curr)
+		symlink (curr->dest, curr->name);
+
+	/* NB: The check for CONFIG_FILE is done in read_config_file() */
+
+	if ( print_version  || (DEVFSD_PROTOCOL_REVISION_DAEMON != proto_rev) )
+	{
+		bb_printf( "%s v%s\nDaemon %s:\t%d\nKernel-side %s:\t%d\n",
+					 bb_applet_name,DEVFSD_VERSION,bb_msg_proto_rev,
+					 DEVFSD_PROTOCOL_REVISION_DAEMON,bb_msg_proto_rev, proto_rev);
+		if (DEVFSD_PROTOCOL_REVISION_DAEMON != proto_rev)
+			bb_error_msg_and_die( "%s mismatch!",bb_msg_proto_rev);
+		exit(EXIT_SUCCESS); /* -v */
+	}
+	/*  Tell kernel we are special (i.e. we get to see hidden entries)  */
+	do_ioctl(DIE, fd, DEVFSDIOC_SET_EVENT_MASK, 0);
+
+	sigemptyset (&new_action.sa_mask);
+	new_action.sa_flags = 0;
+
+	/*  Set up SIGHUP and SIGUSR1 handlers  */
+	new_action.sa_handler = signal_handler;
+	if (sigaction (SIGHUP, &new_action, NULL) != 0 || sigaction (SIGUSR1, &new_action, NULL) != 0 )
+		bb_error_msg_and_die( "sigaction()");
+
+	bb_printf("%s v%s  started for %s\n",bb_applet_name, DEVFSD_VERSION, mount_point);
+
+	/*  Set umask so that mknod(2), open(2) and mkdir(2) have complete control 	over permissions  */
+	umask (0);
+	read_config_file (CONFIG_FILE, FALSE, &event_mask);
+	/*  Do the scan before forking, so that boot scripts see the finished product  */
+	do_scan_and_service (mount_point);
+	if (no_polling)
+		exit (0);
+	if (do_daemon)
+	{
+		/*  Release so that the child can grab it  */
+		do_ioctl(DIE, fd, DEVFSDIOC_RELEASE_EVENT_QUEUE, 0);
+		fork_and_execute(DIE, NULL, NULL);
+		setsid ();        /*  Prevent hangups and become pgrp leader         */
+	}
+	else
+		setpgid (0, 0);  /*  Become process group leader                    */
+
+	while (TRUE)
+	{
+		int do_scan = do_servicing (fd, event_mask);
+
+		free_config ();
+		read_config_file (CONFIG_FILE, FALSE, &event_mask);
+		if (do_scan)
+			do_scan_and_service (mount_point);
+	}
+}   /*  End Function main  */
+
+
+/*  Private functions follow  */
+
+static void read_config_file (const char *path, int optional, unsigned long *event_mask)
+/*  [SUMMARY] Read a configuration database.
+    <path> The path to read the database from. If this is a directory, all
+    entries in that directory will be read (except hidden entries).
+    <optional> If TRUE, the routine will silently ignore a missing config file.
+    <event_mask> The event mask is written here. This is not initialised.
+    [RETURNS] Nothing.
+*/
+{
+	struct stat statbuf;
+	FILE *fp;
+	char buf[STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "read_config_file()\n");
+#endif
+
+	if (stat (path, &statbuf) != 0 || statbuf.st_size == 0 )
+		msg_logger((optional ==  0 )? DIE : NO_DIE, LOG_ERR, " %s: %m\n", path);
+
+	if ( S_ISDIR (statbuf.st_mode) )
+	{
+
+		DIR *dp;
+		struct dirent *de;
+
+		dp = xopendir(DIE, path);
+
+		while ( ( de = readdir (dp) ) != NULL )
+		{
+			char fname[STRING_LENGTH];
+
+			if (de->d_name[0] == '.')
+				continue;
+			snprintf (fname, STRING_LENGTH, "%s/%s", path, de->d_name);
+			read_config_file (fname, optional, event_mask);
+		}
+		closedir (dp);
+		return;
+	}
+
+	if ( ( fp = fopen (path, "r") ) != NULL )
+	{
+		while (fgets (buf, STRING_LENGTH, fp) != NULL)
+		{
+			char *line;
+
+			buf[strlen (buf) - 1] = '\0';
+			/*  Skip whitespace  */
+			for (line = buf; isspace (*line); ++line)
+				/*VOID*/;
+			if (line[0] == '\0' || line[0] == '#' )
+				continue;
+			process_config_line (line, event_mask);
+		}
+		fclose (fp);
+#ifdef CONFIG_DEVFSD_VERBOSE
+		msg_logger( NO_DIE, LOG_INFO, "read config file: %s\n", path);
+#endif
+		return;
+	}
+	msg_logger(( (optional == 0) && (errno == ENOENT) )? DIE : NO_DIE, LOG_ERR, " %s: %m\n", path);
+}   /*  End Function read_config_file   */
+
+static void process_config_line (const char *line, unsigned long *event_mask)
+/*  [SUMMARY] Process a line from a configuration file.
+    <line> The configuration line.
+    <event_mask> The event mask is written here. This is not initialised.
+    [RETURNS] Nothing.
+*/
+{
+	int  num_args, count;
+	struct config_entry_struct *new;
+	char p[MAX_ARGS][STRING_LENGTH];
+	char when[STRING_LENGTH], what[STRING_LENGTH];
+	char name[STRING_LENGTH];
+	char * msg="";
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "process_config_line()\n");
+#endif
+
+	for (count = 0; count < MAX_ARGS; ++count) p[count][0] = '\0';
+	num_args = sscanf (line, "%s %s %s %s %s %s %s %s %s %s",
+			when, name, what,
+			p[0], p[1], p[2], p[3], p[4], p[5], p[6]);
+	if (strcasecmp (when, "CLEAR_CONFIG") == 0)
+	{
+		free_config ();
+		*event_mask = 0;
+		return;
+	}
+	if (num_args < 2)
+		goto process_config_line_err;
+
+	if ( (strcasecmp (when, "INCLUDE") == 0) ||
+		 (strcasecmp (when, "OPTIONAL_INCLUDE") == 0) )
+	{
+		st_expr_expand (name, STRING_LENGTH, name, get_variable, NULL );
+		read_config_file (name, (toupper (when[0]) == 'I') ? FALSE : TRUE, event_mask);
+		return;
+	}
+	if (strcasecmp (when, "RESTORE") == 0)
+	{
+		do_restore ( name, strlen (name) );
+		return;
+	}
+	if (num_args < 3)
+		goto process_config_line_err;
+
+	new = xmalloc (sizeof *new);
+	memset (new, 0, sizeof *new);
+
+	for (count = 0; event_types[count].config_name != NULL; ++count)
+	{
+		if (strcasecmp (when, event_types[count].config_name) != 0)
+			continue;
+		new->action.when = event_types[count].type;
+		break;
+	}
+	if (event_types[count].config_name == NULL)
+	{
+		msg="WHEN in";
+		goto process_config_line_err;
+	}
+
+	if (strcasecmp (what, "PERMISSIONS") == 0)
+	{
+		char *ptr;
+
+		new->action.what = AC_PERMISSIONS;
+		/*  Get user and group  */
+		if ( ( ptr = strchr (p[0], '.') ) == NULL )
+		{
+			msg="UID.GID";
+			goto process_config_line_err; /*"missing '.' in UID.GID */
+		}
+
+		*ptr++ = '\0';
+		new->u.permissions.uid = get_uid_gid (UID, p[0]);
+		new->u.permissions.gid = get_uid_gid (GID, ptr);
+		/*  Get mode  */
+		new->u.permissions.mode = get_mode (p[1]);
+	}
+	else if (strcasecmp (what, "EXECUTE") == 0)
+	{
+		new->action.what = AC_EXECUTE;
+		num_args -= 3;
+
+		for (count = 0; count < num_args; ++count)
+			new->u.execute.argv[count] = bb_xstrdup (p[count]);
+
+		new->u.execute.argv[num_args] = NULL;
+	}
+	else if (strcasecmp (what, "COPY") == 0)
+	{
+		new->action.what = AC_COPY;
+		num_args -= 3;
+		if (num_args != 2)
+			goto process_config_line_err; /* missing path and function in line */
+
+		new->u.copy.source = bb_xstrdup (p[0]);
+		new->u.copy.destination = bb_xstrdup (p[1]);
+	}
+	else if (strcasecmp (what, "IGNORE") == 0)
+		new->action.what = AC_IGNORE;
+	else if (strcasecmp (what, "MKOLDCOMPAT") == 0)
+		new->action.what = AC_MKOLDCOMPAT;
+	else if (strcasecmp (what, "MKNEWCOMPAT") == 0)
+		new->action.what = AC_MKNEWCOMPAT;
+	else if (strcasecmp (what, "RMOLDCOMPAT") == 0)
+		new->action.what = AC_RMOLDCOMPAT;
+	else if (strcasecmp (what, "RMNEWCOMPAT") == 0)
+		new->action.what = AC_RMNEWCOMPAT;
+	else
+	{
+		msg ="WHAT in";
+		goto process_config_line_err;
+	}
+
+	xregcomp( &new->preg, name, REG_EXTENDED);
+
+	*event_mask |= 1 << new->action.when;
+	new->next = NULL;
+	if (first_config == NULL)
+		first_config = new;
+	else
+		last_config->next = new;
+	last_config = new;
+	return;
+process_config_line_err:
+	msg_logger( DIE, LOG_ERR, bb_msg_bad_config, msg , line);
+}  /*  End Function process_config_line   */
+
+static int do_servicing (int fd, unsigned long event_mask)
+/*  [SUMMARY] Service devfs changes until a signal is received.
+    <fd> The open control file.
+    <event_mask> The event mask.
+    [RETURNS] TRUE if SIGHUP was caught, else FALSE.
+*/
+{
+	ssize_t bytes;
+	struct devfsd_notify_struct info;
+	unsigned long tmp_event_mask;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "do_servicing()\n");
+#endif
+	/*  Tell devfs what events we care about  */
+	tmp_event_mask = event_mask;
+	/*  May need to trap inode creates to watch for syslogd(8) starting  */
+	/*if (!syslog_is_open &&  !no_syslog)
+	{
+		tmp_event_mask |= 1 << DEVFSD_NOTIFY_CREATE; *//*FIXME  I'm not sure if this line is needed. TITO */
+	/*}*/
+	do_ioctl(DIE, fd, DEVFSDIOC_SET_EVENT_MASK, tmp_event_mask);
+	while (!caught_signal)
+	{
+		errno = 0;
+		bytes = read (fd, (char *) &info, sizeof info);
+		if (caught_signal)
+			break;      /*  Must test for this first     */
+		if (errno == EINTR)
+			continue;  /*  Yes, the order is important  */
+		if (bytes < 1)
+			break;
+		/*  Special trap for "/dev/log" creation  */
+		/*  Open syslog, now that "/dev/log" exists  */
+		/*if (!syslog_is_open && !no_syslog &&
+			 (info.type == DEVFSD_NOTIFY_CREATE) &&(strcmp (info.devname, "log") == 0) )
+		{
+			do_open_syslog ();
+			do_ioctl(DIE, fd, DEVFSDIOC_SET_EVENT_MASK, event_mask);*/ /*FIXME I'm not sure if this line is needed. TITO */
+		/*}*/
+		service_name (&info);
+	}
+	if (caught_signal)
+	{
+		int c_sighup = caught_sighup;
+
+		caught_signal = FALSE;
+		caught_sighup = FALSE;
+		return (c_sighup);
+	}
+#ifdef CONFIG_DEVFSD_VERBOSE
+	msg_logger( NO_DIE, LOG_ERR, "read error on control file: %m\n");
+#endif
+	/* This is to shut up a compiler warning */
+	exit(1);
+}   /*  End Function do_servicing  */
+
+static void service_name (const struct devfsd_notify_struct *info)
+/*  [SUMMARY] Service a single devfs change.
+    <info> The devfs change.
+    [RETURNS] Nothing.
+*/
+{
+	unsigned int n;
+	regmatch_t mbuf[MAX_SUBEXPR];
+	struct config_entry_struct *entry;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "service_name()\n");
+#endif
+#ifdef CONFIG_DEVFSD_VERBOSE
+	if (info->overrun_count > 0)
+		msg_logger( NO_DIE, LOG_ERR, "lost %u events\n", info->overrun_count);
+#endif
+
+	/*  Discard lookups on "/dev/log" and "/dev/initctl"  */
+	if	(info->type == DEVFSD_NOTIFY_LOOKUP &&
+		(( (strcmp (info->devname, "log") == 0) ||
+		(strcmp (info->devname, "initctl") == 0))))
+			return;
+	for (entry = first_config; entry != NULL; entry = entry->next)
+	{
+		/*  First check if action matches the type, then check if name matches */
+		if (info->type != entry->action.when || regexec (&entry->preg, info->devname, MAX_SUBEXPR, mbuf, 0) != 0 )
+			continue;
+		for (n = 0; (n < MAX_SUBEXPR) && (mbuf[n].rm_so != -1); ++n)
+			/* VOID */;
+		switch (entry->action.what)
+		{
+			case AC_PERMISSIONS:
+#ifdef CONFIG_DEVFSD_DEBUG
+				msg_logger( NO_DIE, LOG_INFO, "AC_PERMISSIONS\n");
+#endif
+				action_permissions (info, entry);
+				break;
+			case AC_EXECUTE:
+#ifdef CONFIG_DEVFSD_DEBUG
+				msg_logger( NO_DIE, LOG_INFO, "AC_EXECUTE\n");
+#endif
+				action_execute (info, entry, mbuf, n);
+				break;
+			case AC_COPY:
+#ifdef CONFIG_DEVFSD_DEBUG
+				msg_logger( NO_DIE, LOG_INFO, "AC_COPY\n");
+#endif
+				action_copy (info, entry, mbuf, n);
+				break;
+			case AC_IGNORE:
+#ifdef CONFIG_DEVFSD_DEBUG
+				msg_logger( NO_DIE, LOG_INFO, "AC_IGNORE\n");
+#endif
+				return;
+				/*break;*/
+			case AC_MKOLDCOMPAT:
+			case AC_MKNEWCOMPAT:
+			case AC_RMOLDCOMPAT:
+			case AC_RMNEWCOMPAT:
+#ifdef CONFIG_DEVFSD_DEBUG
+				msg_logger( NO_DIE, LOG_INFO, "AC_COMPAT\n");
+#endif
+				action_compat (info, entry->action.what);
+				break;
+			default:
+				msg_logger( DIE, LOG_ERR, "Unknown action\n");
+				/*break;*/
+		}
+	}
+}   /*  End Function service_name  */
+
+static void action_permissions (const struct devfsd_notify_struct *info,
+				const struct config_entry_struct *entry)
+/*  [SUMMARY] Update permissions for a device entry.
+    <info> The devfs change.
+    <entry> The config file entry.
+    [RETURNS] Nothing.
+*/
+{
+	struct stat statbuf;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "action_permission()\n");
+#endif
+
+	if ( stat (info->devname, &statbuf) != 0	||
+		 chmod (info->devname,(statbuf.st_mode & S_IFMT) | (entry->u.permissions.mode & ~S_IFMT)) != 0 ||
+		 chown (info->devname, entry->u.permissions.uid, entry->u.permissions.gid) != 0)
+	{
+#ifdef CONFIG_DEVFSD_VERBOSE
+			msg_logger( NO_DIE, LOG_ERR, "chmod() or chown() error for: %s: %m\n",info->devname);
+#endif
+		return;
+	}
+
+}   /*  End Function action_permissions  */
+
+static void action_execute (const struct devfsd_notify_struct *info,
+			    const struct config_entry_struct *entry,
+			    const regmatch_t *regexpr, unsigned int numexpr)
+/*  [SUMMARY] Execute a programme.
+    <info> The devfs change.
+    <entry> The config file entry.
+    <regexpr> The number of subexpression (start, end) offsets within the
+    device name.
+    <numexpr> The number of elements within <<regexpr>>.
+    [RETURNS] Nothing.
+*/
+{
+	unsigned int count;
+	struct get_variable_info gv_info;
+	char *argv[MAX_ARGS + 1];
+	char largv[MAX_ARGS + 1][STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "action_execute()\n");
+#endif
+
+	gv_info.info = info;
+	gv_info.devname = info->devname;
+	snprintf (gv_info.devpath, sizeof (gv_info.devpath), "%s/%s", mount_point, info->devname);
+	for (count = 0; entry->u.execute.argv[count] != NULL; ++count)
+	{
+		expand_expression (largv[count], STRING_LENGTH,
+				entry->u.execute.argv[count],
+				get_variable, &gv_info,
+				gv_info.devname, regexpr, numexpr );
+		argv[count] = largv[count];
+	}
+	argv[count] = NULL;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	int i;
+	char buff[1024];
+
+	buff[0]='\0';
+	for(i=0;argv[i]!=NULL;i++) /* argv[i] < MAX_ARGS + 1 */
+	{
+		strcat(buff," ");
+		if( (strlen(buff)+ 1 + strlen(argv[i])) >= 1024)
+			break;
+		strcat(buff,argv[i]);
+	}
+	strcat(buff,"\n");
+	msg_logger( NO_DIE, LOG_INFO, "action_execute(): %s",buff);
+#endif
+
+	fork_and_execute(NO_DIE, argv[0], argv);
+}   /*  End Function action_execute  */
+
+
+static void action_copy (const struct devfsd_notify_struct *info,
+			 const struct config_entry_struct *entry,
+                         const regmatch_t *regexpr, unsigned int numexpr)
+/*  [SUMMARY] Copy permissions.
+    <info> The devfs change.
+    <entry> The config file entry.
+    <regexpr> This list of subexpression (start, end) offsets within the
+    device name.
+    <numexpr> The number of elements in <<regexpr>>.
+    [RETURNS] Nothing.
+*/
+{
+	mode_t new_mode;
+	struct get_variable_info gv_info;
+	struct stat source_stat, dest_stat;
+	char source[STRING_LENGTH], destination[STRING_LENGTH];
+	dest_stat.st_mode = 0;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "action_copy()\n");
+#endif
+
+	if ( (info->type == DEVFSD_NOTIFY_CHANGE) && S_ISLNK (info->mode) )
+		return;
+	gv_info.info = info;
+	gv_info.devname = info->devname;
+	snprintf (gv_info.devpath, sizeof (gv_info.devpath), "%s/%s", mount_point, info->devname);
+
+	expand_expression (source, STRING_LENGTH, entry->u.copy.source,
+				get_variable, &gv_info, gv_info.devname,
+				regexpr, numexpr);
+
+	expand_expression (destination, STRING_LENGTH, entry->u.copy.destination,
+				get_variable, &gv_info, gv_info.devname,
+				regexpr, numexpr);
+
+	if ( !make_dir_tree (destination) || lstat (source, &source_stat) != 0)
+		goto action_copy_error;
+
+	lstat (destination, &dest_stat);
+	new_mode = source_stat.st_mode & ~S_ISVTX;
+	if (info->type == DEVFSD_NOTIFY_CREATE)
+		new_mode |= S_ISVTX;
+	else if ( (info->type == DEVFSD_NOTIFY_CHANGE) && (dest_stat.st_mode & S_ISVTX) )
+		new_mode |= S_ISVTX;
+#ifdef CONFIG_DEVFSD_VERBOSE
+	if ( !copy_inode (destination, &dest_stat, new_mode, source, &source_stat) )
+action_copy_error:
+		msg_logger( NO_DIE, LOG_ERR, "error copying: %s to %s: %m\n", source, destination);
+#else
+	copy_inode (destination, &dest_stat, new_mode, source,&source_stat);
+action_copy_error:
+	return;
+#endif
+}   /*  End Function action_copy  */
+
+static void action_compat (const struct devfsd_notify_struct *info,
+			   unsigned int action)
+/*  [SUMMARY] Process a compatibility request.
+    <info> The devfs change.
+    <action> The action to take.
+    [RETURNS] Nothing.
+*/
+{
+	const char *compat_name = NULL;
+	const char *dest_name = info->devname;
+	char *ptr;
+	char compat_buf[STRING_LENGTH], dest_buf[STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "action_compat()\n");
+#endif
+
+	/*  First construct compatibility name  */
+	switch (action)
+	{
+		case AC_MKOLDCOMPAT:
+		case AC_RMOLDCOMPAT:
+			compat_name = get_old_name (info->devname, info->namelen, compat_buf, info->major, info->minor);
+			break;
+		case AC_MKNEWCOMPAT:
+		case AC_RMNEWCOMPAT:
+		if (strncmp (info->devname, "scsi/", 5) == 0)
+		{
+			int mode, host, bus, target, lun;
+
+			sscanf (info->devname + 5, "host%d/bus%d/target%d/lun%d/",
+				&host, &bus, &target, &lun);
+			compat_name = compat_buf;
+			snprintf (dest_buf, sizeof (dest_buf), "../%s", info->devname);
+			dest_name = dest_buf;
+			if (strncmp (ptr = (strrchr (info->devname, '/') + 1), "mt", 2)== 0)
+			{
+				char rewind_ = info->devname[info->namelen - 1];
+
+				if (rewind_ != 'n')
+					rewind_ = '\0';
+
+				switch (ptr[2])
+				{
+					default:
+						mode = 0;
+						break;
+					case 'l':
+						mode = 1;
+						break;
+					case 'm':
+						mode = 2;
+						break;
+					case 'a':
+						mode = 3;
+						break;
+				}
+				sprintf (compat_buf, "st/c%db%dt%du%dm%d%c", host, bus, target, lun, mode, rewind_);
+			}
+			else if (strcmp (info->devname + info->namelen - 7,"generic") == 0)
+				sprintf (compat_buf, "sg/c%db%dt%du%d",
+						host, bus, target, lun);
+			else if (strcmp (info->devname + info->namelen - 2, "cd") == 0)
+				sprintf (compat_buf, "sr/c%db%dt%du%d",
+						host, bus, target, lun);
+			else if (strcmp (info->devname + info->namelen - 4, "disc") == 0)
+				sprintf (compat_buf, "sd/c%db%dt%du%d",
+						host, bus, target, lun);
+			else if (strncmp (ptr = (strrchr (info->devname, '/') + 1), "part", 4) == 0)
+				sprintf ( compat_buf, "sd/c%db%dt%du%dp%d",
+						host, bus, target, lun, atoi (ptr + 4) );
+			else compat_name = NULL;
+		}
+		else if (strncmp (info->devname, "ide/host", 8) == 0)
+		{
+			int host, bus, target, lun;
+
+			sscanf (info->devname + 4, "host%d/bus%d/target%d/lun%d/",
+				&host, &bus, &target, &lun);
+			compat_name = compat_buf;
+			snprintf (dest_buf, sizeof (dest_buf), "../%s", info->devname + 4);
+			dest_name = dest_buf;
+			if (strcmp (info->devname + info->namelen - 4, "disc") == 0)
+				sprintf (compat_buf, "ide/hd/c%db%dt%du%d",
+					host, bus, target, lun);
+			else if (strncmp (ptr = (strrchr (info->devname, '/') + 1), "part", 4) == 0)
+				sprintf ( compat_buf, "ide/hd/c%db%dt%du%dp%d",
+					host, bus, target, lun, atoi (ptr + 4) );
+			else if (strcmp (info->devname + info->namelen - 2, "cd") == 0)
+				sprintf (compat_buf, "ide/cd/c%db%dt%du%d",
+					host, bus, target,lun);
+			else if (strncmp (ptr = (strrchr (info->devname, '/') + 1), "mt", 2) == 0)
+				snprintf (compat_buf, sizeof (compat_buf), "ide/mt/c%db%dt%du%d%s",
+					host, bus, target, lun, ptr + 2);
+			else compat_name = NULL;
+		}
+		break;
+	}
+	if (compat_name == NULL)
+		return;
+	/*  Now decide what to do with it  */
+	switch (action)
+	{
+		case AC_MKOLDCOMPAT:
+		case AC_MKNEWCOMPAT:
+			mksymlink (dest_name, compat_name);
+			break;
+		case AC_RMOLDCOMPAT:
+		case AC_RMNEWCOMPAT:
+#ifdef CONFIG_DEVFSD_VERBOSE
+			if (unlink (compat_name) != 0)
+				msg_logger( NO_DIE, LOG_ERR, "unlink(): %s: %m\n", compat_name);
+#else
+			unlink (compat_name);
+#endif
+			break;
+	}
+}   /*  End Function action_compat  */
+
+static void do_restore (const char *dir_name, int rootlen)
+/*  [SUMMARY] Restore state from a directory.
+    <dir_name> The directory containing the backing store.
+    <rootlen> The length of the root of the state directory hierarchy.
+    [RETURNS] Nothing.
+*/
+{
+	DIR *dp;
+	struct dirent *de;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "do_restore()\n");
+#endif
+
+	if( (dp = xopendir(NO_DIE, dir_name))== NULL)
+		return;
+
+	while ( (de = readdir (dp) ) != NULL )
+	{
+		char spath[STRING_LENGTH], dpath[STRING_LENGTH];
+
+		struct stat source_stat, dest_stat;
+		dest_stat.st_mode = 0;
+
+		if ( (strcmp (de->d_name, ".") == 0) || (strcmp (de->d_name, "..") == 0) )
+			continue;
+
+		snprintf (spath, sizeof spath, "%s/%s", dir_name, de->d_name);
+
+		if (lstat (spath, &source_stat) != 0)
+		{
+#ifdef CONFIG_DEVFSD_VERBOSE
+			msg_logger( NO_DIE, LOG_ERR, "%s: %m\n", spath);
+#endif
+			continue;
+		}
+		snprintf (dpath, sizeof dpath, "%s%s", mount_point, spath + rootlen);
+		lstat (dpath, &dest_stat);
+
+		if ( S_ISLNK (source_stat.st_mode) || (source_stat.st_mode & S_ISVTX) )
+			copy_inode (dpath, &dest_stat, (source_stat.st_mode & ~S_ISVTX) , spath, &source_stat);
+
+		if ( S_ISDIR (source_stat.st_mode) )
+			do_restore (spath, rootlen);
+	}
+	closedir (dp);
+}   /*  End Function do_restore  */
+
+static int copy_inode (const char *destpath, const struct stat *dest_stat,
+			mode_t new_mode,
+			const char *sourcepath, const struct stat *source_stat)
+/*  [SUMMARY] Copy an inode.
+    <destpath> The destination path. An existing inode may be deleted.
+    <dest_stat> The destination stat(2) information.
+    <new_mode> The desired new mode for the destination.
+    <sourcepath> The source path.
+    <source_stat> The source stat(2) information.
+    [RETURNS] TRUE on success, else FALSE.
+*/
+{
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "copy_inode()\n");
+#endif
+
+	if ( (source_stat->st_mode & S_IFMT) == (dest_stat->st_mode & S_IFMT) )
+	{
+		/*  Same type  */
+		if ( S_ISLNK (source_stat->st_mode) )
+		{
+			int source_len, dest_len;
+			char source_link[STRING_LENGTH], dest_link[STRING_LENGTH];
+
+
+			if (( source_len = readlink (sourcepath, source_link, STRING_LENGTH - 1) ) < 0 ||
+				( dest_len   = readlink (destpath  , dest_link  , STRING_LENGTH - 1) ) < 0 )
+				return (FALSE);
+			source_link[source_len]	= '\0';
+			dest_link[dest_len] 	= '\0';
+			if ( (source_len != dest_len) || (strcmp (source_link, dest_link) != 0) )
+			{
+				unlink (destpath);
+				symlink (source_link, destpath);
+			}
+			return (TRUE);
+		}   /*  Else not a symlink  */
+		chmod (destpath, new_mode & ~S_IFMT);
+		chown (destpath, source_stat->st_uid, source_stat->st_gid);
+		return (TRUE);
+	}
+	/*  Different types: unlink and create  */
+	unlink (destpath);
+	switch (source_stat->st_mode & S_IFMT)
+	{
+		int fd, val;
+		struct sockaddr_un un_addr;
+		char symlink_val[STRING_LENGTH];
+
+		case S_IFSOCK:
+			if ( ( fd = socket (AF_UNIX, SOCK_STREAM, 0) ) < 0 )
+				break;
+			un_addr.sun_family = AF_UNIX;
+			snprintf (un_addr.sun_path, sizeof (un_addr.sun_path), "%s", destpath);
+			val = bind (fd, (struct sockaddr *) &un_addr, (int) sizeof un_addr);
+			close (fd);
+			if (val != 0 || chmod (destpath, new_mode & ~S_IFMT) != 0)
+				break;
+			if (chown (destpath, source_stat->st_uid, source_stat->st_gid) == 0)
+				return (TRUE);
+			break;
+		case S_IFLNK:
+			if ( ( val = readlink (sourcepath, symlink_val, STRING_LENGTH - 1) ) < 0 )
+				break;
+			symlink_val[val] = '\0';
+			if (symlink (symlink_val, destpath) == 0)
+				return (TRUE);
+			break;
+		case S_IFREG:
+			if ( ( fd = open (destpath, O_RDONLY | O_CREAT, new_mode & ~S_IFMT) ) < 0 )
+				break;
+			close (fd);
+			if (chmod (destpath, new_mode & ~S_IFMT) != 0)
+				break;
+			if (chown (destpath, source_stat->st_uid, source_stat->st_gid) == 0)
+				return (TRUE);
+			break;
+		case S_IFBLK:
+		case S_IFCHR:
+		case S_IFIFO:
+			if (mknod (destpath, new_mode, source_stat->st_rdev) != 0)
+				break;
+			if (chown (destpath, source_stat->st_uid, source_stat->st_gid) == 0)
+				return (TRUE);
+			break;
+		case S_IFDIR:
+			if (mkdir (destpath, new_mode & ~S_IFMT) != 0)
+				break;
+			if (chown (destpath, source_stat->st_uid, source_stat->st_gid) == 0)
+				return (TRUE);
+			return (TRUE);
+		/*break;*/
+	}
+	return (FALSE);
+}   /*  End Function copy_inode  */
+
+static void free_config ()
+/*  [SUMMARY] Free the configuration information.
+    [RETURNS] Nothing.
+*/
+{
+	struct config_entry_struct *c_entry;
+	void *next;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "free_config()\n");
+#endif
+
+	for (c_entry = first_config; c_entry != NULL; c_entry = next)
+	{
+		unsigned int count;
+
+		next = c_entry->next;
+		regfree (&c_entry->preg);
+		if (c_entry->action.what == AC_EXECUTE)
+		{
+			for (count = 0; count < MAX_ARGS; ++count)
+			{
+				if (c_entry->u.execute.argv[count] == NULL)
+					break;
+				free (c_entry->u.execute.argv[count]);
+			}
+		}
+		free (c_entry);
+	}
+	first_config = NULL;
+	last_config = NULL;
+}   /*  End Function free_config  */
+
+static int get_uid_gid (int flag, const char *string)
+/*  [SUMMARY] Convert a string to a UID or GID value.
+	<flag> "UID" or "GID".
+	<string> The string.
+    [RETURNS] The UID or GID value.
+*/
+{
+	struct passwd *pw_ent;
+	struct group *grp_ent;
+	char * msg_a="user";
+	char * msg_b="U";
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "get_uid_gid()\n");
+
+
+	if(flag != UID && flag != GID )
+		msg_logger( DIE, LOG_ERR,"flag != UID && flag != GID\n");
+#endif
+
+	if ( isdigit (string[0]) || ( (string[0] == '-') && isdigit (string[1]) ) )
+		return atoi (string);
+
+	if ( flag == UID && ( pw_ent  = getpwnam (string) ) != NULL )
+		return (pw_ent->pw_uid);
+
+	if ( flag == GID && ( grp_ent = getgrnam (string) ) != NULL )
+		return (grp_ent->gr_gid);
+	else
+	{
+		msg_a="group";
+		msg_b="G";
+	}
+
+	msg_logger( NO_DIE, LOG_ERR,"unknown %s: %s, defaulting to %cID=0\n", msg_a, string, msg_b);
+	return (0);
+}/*  End Function get_uid_gid  */
+
+static mode_t get_mode (const char *string)
+/*  [SUMMARY] Convert a string to a mode value.
+    <string> The string.
+    [RETURNS] The mode value.
+*/
+{
+	mode_t mode;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "get_mode()\n");
+#endif
+
+	if ( isdigit (string[0]) )
+		return strtoul (string, NULL, 8);
+	if (strlen (string) != 9)
+		msg_logger( DIE, LOG_ERR, "bad mode: %s\n", string);
+	mode = 0;
+	if (string[0] == 'r') mode |= S_IRUSR;
+	if (string[1] == 'w') mode |= S_IWUSR;
+	if (string[2] == 'x') mode |= S_IXUSR;
+	if (string[3] == 'r') mode |= S_IRGRP;
+	if (string[4] == 'w') mode |= S_IWGRP;
+	if (string[5] == 'x') mode |= S_IXGRP;
+	if (string[6] == 'r') mode |= S_IROTH;
+	if (string[7] == 'w') mode |= S_IWOTH;
+	if (string[8] == 'x') mode |= S_IXOTH;
+	return (mode);
+}   /*  End Function get_mode  */
+
+static void signal_handler (int sig)
+{
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "signal_handler()\n");
+#endif
+
+	caught_signal = TRUE;
+	if (sig == SIGHUP)
+		caught_sighup = TRUE;
+#ifdef CONFIG_DEVFSD_VERBOSE
+	msg_logger( NO_DIE, LOG_INFO, "Caught %s\n",(sig == SIGHUP)?"SIGHUP" : "SIGUSR1");
+#endif
+}   /*  End Function signal_handler  */
+
+static const char *get_variable (const char *variable, void *info)
+{
+	struct get_variable_info *gv_info = info;
+	static char hostname[STRING_LENGTH], sbuf[STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "get_variable()\n");
+#endif
+
+	if (gethostname (hostname, STRING_LENGTH - 1) != 0)
+		msg_logger( DIE, LOG_ERR, "gethostname(): %m\n");
+		/* Here on error we should do exit(RV_SYS_ERROR), instead we do exit(EXIT_FAILURE) */
+	hostname[STRING_LENGTH - 1] = '\0';
+	if (strcmp (variable, "hostname") == 0)
+		return (hostname);
+	if (strcmp (variable, "mntpnt") == 0)
+		return (mount_point);
+	if (gv_info == NULL)
+		return (NULL);
+	if (strcmp (variable, "devpath") == 0)
+		return (gv_info->devpath);
+	if (strcmp (variable, "devname") == 0)
+		return (gv_info->devname);
+	if (strcmp (variable, "mode") == 0)
+	{
+		sprintf (sbuf, "%o", gv_info->info->mode);
+		return (sbuf);
+	}
+	if (strcmp (variable, "uid") == 0)
+	{
+		sprintf (sbuf, "%u", gv_info->info->uid);
+		return (sbuf);
+	}
+	if (strcmp (variable, "gid") == 0)
+	{
+		sprintf (sbuf, "%u", gv_info->info->gid);
+		return (sbuf);
+	}
+	return (NULL);
+}   /*  End Function get_variable  */
+
+static void do_scan_and_service (const char *dir_name)
+/*  [SUMMARY] Scan a directory tree and generate register events on leaf nodes.
+    <dp> The directory pointer. This is closed upon completion.
+    <dir_name> The name of the directory.
+    [RETURNS] Nothing.
+*/
+{
+	struct stat statbuf;
+	DIR *dp;
+	struct dirent *de;
+	char path[STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "do_scan_and_service ()\n");
+#endif
+
+	if((dp = xopendir(NO_DIE, dir_name))==NULL)
+		return;
+
+	while ( (de = readdir (dp) ) != NULL )
+	{
+		struct devfsd_notify_struct info;
+
+		if ( (strcmp (de->d_name, ".") == 0) || (strcmp (de->d_name, "..") == 0) )
+			continue;
+		snprintf (path, sizeof (path), "%s/%s", dir_name, de->d_name);
+		if (lstat (path, &statbuf) != 0)
+		{
+#ifdef CONFIG_DEVFSD_VERBOSE
+			msg_logger( NO_DIE, LOG_ERR, "%s: %m\n", path);
+#endif
+			continue;
+		}
+		memset (&info, 0, sizeof info);
+		info.type = DEVFSD_NOTIFY_REGISTERED;
+		info.mode = statbuf.st_mode;
+		info.major = MAJOR (statbuf.st_rdev);
+		info.minor = MINOR (statbuf.st_rdev);
+		info.uid = statbuf.st_uid;
+		info.gid = statbuf.st_gid;
+		snprintf (info.devname, sizeof (info.devname), "%s", path + strlen (mount_point) + 1);
+		info.namelen = strlen (info.devname);
+		service_name (&info);
+		if ( S_ISDIR (statbuf.st_mode) )
+			do_scan_and_service (path);
+	}
+	closedir (dp);
+}   /*  End Function do_scan_and_service  */
+
+static int mksymlink (const char *oldpath, const char *newpath)
+/*  [SUMMARY] Create a symlink, creating intervening directories as required.
+    <oldpath> The string contained in the symlink.
+    <newpath> The name of the new symlink.
+    [RETURNS] 0 on success, else -1.
+*/
+{
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "mksymlink()\n", newpath);
+#endif
+
+
+	if ( !make_dir_tree (newpath) )
+		return (-1);
+
+	if (symlink (oldpath, newpath) != 0)
+    {
+#ifdef CONFIG_DEVFSD_VERBOSE
+		if (errno == EEXIST)
+			msg_logger( NO_DIE, LOG_INFO, "symlink(): %s: already exists\n", newpath);
+		else
+		{
+			msg_logger( NO_DIE, LOG_ERR, "symlink(): %s: %m\n", newpath);
+			return (-1);
+		}
+#else
+		if (errno != EEXIST)
+			return (-1);
+#endif
+	}
+    return (0);
+}   /*  End Function mksymlink  */
+
+
+static int make_dir_tree (const char *path)
+/*  [SUMMARY] Creating intervening directories for a path as required.
+    <path> The full pathname (including he leaf node).
+    [RETURNS] TRUE on success, else FALSE.
+*/
+{
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "make_dir_tree()\n");
+#endif
+
+	if (bb_make_directory( (char *)path,  S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH , FILEUTILS_RECUR )==-1)
+	{
+#ifdef CONFIG_DEVFSD_VERBOSE
+		msg_logger( NO_DIE, LOG_ERR, "make_dir_tree(): %s: %m\n", path);
+#endif
+		return (FALSE);
+	}
+	return(TRUE);
+} /*  End Function make_dir_tree  */
+
+static int expand_expression(char *output, unsigned int outsize,
+			      const char *input,
+			      const char *(*get_variable_func)(const char *variable, void *info),
+                              void *info,
+                              const char *devname,
+                              const regmatch_t *ex, unsigned int numexp)
+/*  [SUMMARY] Expand enviroment variables and regular subexpressions in string.
+    <output> The output expanded expression is written here.
+    <length> The size of the output buffer.
+    <input> The input expression. This may equal <<output>>.
+    <get_variable> A function which will be used to get variable values. If
+    this returns NULL, the environment is searched instead. If this is NULL,
+    only the environment is searched.
+    <info> An arbitrary pointer passed to <<get_variable>>.
+    <devname> Device name; specifically, this is the string that contains all
+    of the regular subexpressions.
+    <ex> Array of start / end offsets into info->devname for each subexpression
+    <numexp> Number of regular subexpressions found in <<devname>>.
+    [RETURNS] TRUE on success, else FALSE.
+*/
+{
+	char temp[STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "expand_expression()\n");
+#endif
+
+	if ( !st_expr_expand (temp, STRING_LENGTH, input, get_variable_func, info) )
+		return (FALSE);
+	expand_regexp (output, outsize, temp, devname, ex, numexp);
+	return (TRUE);
+}   /*  End Function expand_expression  */
+
+static void expand_regexp (char *output, size_t outsize, const char *input,
+			   const char *devname,
+			   const regmatch_t *ex, unsigned int numex )
+/*  [SUMMARY] Expand all occurrences of the regular subexpressions \0 to \9.
+    <output> The output expanded expression is written here.
+    <outsize> The size of the output buffer.
+    <input> The input expression. This may NOT equal <<output>>, because
+    supporting that would require yet another string-copy. However, it's not
+    hard to write a simple wrapper function to add this functionality for those
+    few cases that need it.
+    <devname> Device name; specifically, this is the string that contains all
+    of the regular subexpressions.
+    <ex> An array of start and end offsets into <<devname>>, one for each
+    subexpression
+    <numex> Number of subexpressions in the offset-array <<ex>>.
+    [RETURNS] Nothing.
+*/
+{
+	const char last_exp = '0' - 1 + numex;
+	int c = -1;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "expand_regexp()\n");
+#endif
+
+	/*  Guarantee NULL termination by writing an explicit '\0' character into
+	the very last byte  */
+	if (outsize)
+		output[--outsize] = '\0';
+	/*  Copy the input string into the output buffer, replacing '\\' with '\'
+	and '\0' .. '\9' with subexpressions 0 .. 9, if they exist. Other \x
+	codes are deleted  */
+	while ( (c != '\0') && (outsize != 0) )
+	{
+		c = *input;
+		++input;
+		if (c == '\\')
+		{
+			c = *input;
+			++input;
+			if (c != '\\')
+			{
+				if ((c >= '0') && (c <= last_exp))
+				{
+					const regmatch_t *subexp = ex + (c - '0');
+					unsigned int sublen = subexp->rm_eo - subexp->rm_so;
+
+					/*  Range checking  */
+					if (sublen > outsize)
+						sublen = outsize;
+					strncpy (output, devname + subexp->rm_so, sublen);
+					output += sublen;
+					outsize -= sublen;
+				}
+				continue;
+			}
+		}
+		*output = c;
+		++output;
+		--outsize;
+	} /* while */
+}   /*  End Function expand_regexp  */
+
+
+/* from compat_name.c */
+
+struct translate_struct
+{
+	char *match;    /*  The string to match to (up to length)                */
+	char *format;   /*  Format of output, "%s" takes data past match string,
+			NULL is effectively "%s" (just more efficient)       */
+};
+
+static struct translate_struct translate_table[] =
+{
+	{"sound/",     NULL},
+	{"printers/",  "lp%s"},
+	{"v4l/",       NULL},
+	{"parports/",  "parport%s"},
+	{"fb/",        "fb%s"},
+	{"netlink/",   NULL},
+	{"loop/",      "loop%s"},
+	{"floppy/",    "fd%s"},
+	{"rd/",        "ram%s"},
+	{"md/",        "md%s"},         /*  Meta-devices                         */
+	{"vc/",        "tty%s"},
+	{"misc/",      NULL},
+	{"isdn/",      NULL},
+	{"pg/",        "pg%s"},         /*  Parallel port generic ATAPI interface*/
+	{"i2c/",       "i2c-%s"},
+	{"staliomem/", "staliomem%s"},  /*  Stallion serial driver control       */
+	{"tts/E",      "ttyE%s"},       /*  Stallion serial driver               */
+	{"cua/E",      "cue%s"},        /*  Stallion serial driver callout       */
+	{"tts/R",      "ttyR%s"},       /*  Rocketport serial driver             */
+	{"cua/R",      "cur%s"},        /*  Rocketport serial driver callout     */
+	{"ip2/",       "ip2%s"},        /*  Computone serial driver control      */
+	{"tts/F",      "ttyF%s"},       /*  Computone serial driver              */
+	{"cua/F",      "cuf%s"},        /*  Computone serial driver callout      */
+	{"tts/C",      "ttyC%s"},       /*  Cyclades serial driver               */
+	{"cua/C",      "cub%s"},        /*  Cyclades serial driver callout       */
+	{"tts/",       "ttyS%s"},       /*  Generic serial: must be after others */
+	{"cua/",       "cua%s"},        /*  Generic serial: must be after others */
+	{"input/js",   "js%s"},         /*  Joystick driver                      */
+	{NULL,         NULL}
+};
+
+const char *get_old_name (const char *devname, unsigned int namelen,
+			  char *buffer, unsigned int major, unsigned int minor)
+/*  [SUMMARY] Translate a kernel-supplied name into an old name.
+    <devname> The device name provided by the kernel.
+    <namelen> The length of the name.
+    <buffer> A buffer that may be used. This should be at least 128 bytes long.
+    <major> The major number for the device.
+    <minor> The minor number for the device.
+    [RETURNS] A pointer to the old name if known, else NULL.
+*/
+{
+	const char *compat_name = NULL;
+	char *ptr;
+	struct translate_struct *trans;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "get_old_name()\n");
+#endif
+
+	for (trans = translate_table; trans->match != NULL; ++trans)
+	{
+		size_t len = strlen (trans->match);
+
+		if (strncmp (devname, trans->match, len) == 0)
+		{
+			if (trans->format == NULL)
+				return (devname + len);
+			sprintf (buffer, trans->format, devname + len);
+			return (buffer);
+		}
+	}
+	if (strncmp (devname, "sbp/", 4) == 0)
+	{
+		sprintf (buffer, "sbpcd%u", minor);
+		compat_name = buffer;
+	}
+	else if (strncmp (devname, "scsi/", 5) == 0)
+	{   /*  All SCSI devices  */
+		if (strcmp (devname + namelen - 7, "generic") == 0)
+		{
+			sprintf (buffer, "sg%u", minor);
+			compat_name = buffer;
+		}
+		else if (strncmp (ptr = (strrchr (devname, '/') + 1), "mt", 2) == 0)
+		{
+			char mode = ptr[2];
+
+			if (mode == 'n')
+				mode = '\0';
+			sprintf (buffer, "nst%u%c", minor & 0x1f, mode);
+			compat_name = buffer;
+			if (devname[namelen - 1] != 'n')
+				++compat_name;
+		}
+		else if (strcmp (devname + namelen - 2, "cd") == 0)
+		{
+			sprintf (buffer, "sr%u", minor);
+			compat_name = buffer;
+		}
+		else if (strcmp (devname + namelen - 4, "disc") == 0)
+			compat_name = write_old_sd_name (buffer, major, minor, "");
+		else if (strncmp (ptr = (strrchr (devname, '/') + 1), "part", 4) == 0)
+			compat_name = write_old_sd_name (buffer, major, minor, ptr + 4);
+		return (compat_name);
+	}
+	else if (strncmp (devname, "ide/host", 8) == 0)
+	{   /*  All IDE devices  */
+		if (strncmp (ptr = (strrchr (devname, '/') + 1), "mt", 2) == 0)
+		{
+			sprintf (buffer, "%sht%d", ptr + 2, minor & 0x7f);
+			compat_name = buffer;
+		}
+		else if (strcmp (devname + namelen - 4, "disc") == 0)
+		{
+			sprintf ( buffer, "hd%c", get_old_ide_name (major, minor) );
+			compat_name = buffer;
+		}
+		else if (strncmp (ptr = (strrchr (devname, '/') + 1), "part", 4) == 0)
+		{
+			sprintf (buffer, "hd%c%s", get_old_ide_name (major, minor), ptr + 4);
+			compat_name = buffer;
+		}
+		else if (strcmp (devname + namelen - 2, "cd") == 0)
+		{
+			sprintf ( buffer, "hd%c", get_old_ide_name (major, minor) );
+			compat_name = buffer;
+		}
+		return (compat_name);
+	}
+	else if (strncmp (devname, "vcc/", 4) == 0)
+	{
+		sprintf (buffer, "vcs%s", devname + 4);
+		if (buffer[3] == '0')
+			buffer[3] = '\0';
+		compat_name = buffer;
+	}
+	else if (strncmp (devname, "pty/", 4) == 0)
+	{
+		int indexx = atoi (devname + 5);
+		const char *pty1 = "pqrstuvwxyzabcde";
+		const char *pty2 = "0123456789abcdef";
+
+		sprintf (buffer, "%cty%c%c", (devname[4] == 'm') ? 'p' : 't', pty1[indexx >> 4], pty2[indexx & 0x0f]);
+		compat_name = buffer;
+	}
+	return (compat_name);
+}   /*  End Function get_old_name  */
+
+static char get_old_ide_name (unsigned int major, unsigned int minor)
+/*  [SUMMARY] Get the old IDE name for a device.
+    <major> The major number for the device.
+    <minor> The minor number for the device.
+    [RETURNS] The drive letter.
+*/
+{
+	char letter='y';	/* 121 */
+	char c='a'; 		/*  97 */
+	int i=IDE0_MAJOR;
+
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "get_old_ide_name()\n");
+#endif
+
+	/* I hope it works like the previous code as it saves a few bytes. Tito ;P */
+	do {
+		if(	i==IDE0_MAJOR || i==IDE1_MAJOR || i==IDE2_MAJOR ||
+			i==IDE3_MAJOR || i==IDE4_MAJOR || i==IDE5_MAJOR ||
+			i==IDE6_MAJOR || i==IDE7_MAJOR || i==IDE8_MAJOR ||
+			i==IDE9_MAJOR )
+		{
+			if(i==major)
+			{
+				letter=c;
+				break;
+			}
+			c+=2;
+		}
+		i++;
+	} while(i<=IDE9_MAJOR);
+
+	if (minor > 63)
+		++letter;
+	return (letter);
+}   /*  End Function get_old_ide_name  */
+
+static char *write_old_sd_name (char *buffer,
+				unsigned int major, unsigned int minor,
+				char *part)
+/*  [SUMMARY] Write the old SCSI disc name to a buffer.
+    <buffer> The buffer to write to.
+    <major> The major number for the device.
+    <minor> The minor number for the device.
+    <part> The partition string. Must be "" for a whole-disc entry.
+    [RETURNS] A pointer to the buffer on success, else NULL.
+*/
+{
+	unsigned int disc_index;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "write_old_sd_name()\n");
+#endif
+
+	if (major == 8)
+	{
+		sprintf (buffer, "sd%c%s", 'a' + (minor >> 4), part);
+		return (buffer);
+	}
+	if ( (major > 64) && (major < 72) )
+	{
+		disc_index = ( (major - 64) << 4 ) + (minor >> 4);
+		if (disc_index < 26)
+			sprintf (buffer, "sd%c%s", 'a' + disc_index, part);
+		else
+			sprintf (buffer, "sd%c%c%s", 'a' + (disc_index / 26) - 1, 'a' + disc_index % 26,part);
+		return (buffer);
+	}
+	return (NULL);
+}   /*  End Function write_old_sd_name  */
+
+
+/*  expression.c */
+
+/*EXPERIMENTAL_FUNCTION*/
+
+int st_expr_expand (char *output, unsigned int length, const char *input,
+		     const char *(*get_variable_func) (const char *variable,
+						  void *info),
+		     void *info)
+/*  [SUMMARY] Expand an expression using Borne Shell-like unquoted rules.
+    <output> The output expanded expression is written here.
+    <length> The size of the output buffer.
+    <input> The input expression. This may equal <<output>>.
+    <get_variable> A function which will be used to get variable values. If
+    this returns NULL, the environment is searched instead. If this is NULL,
+    only the environment is searched.
+    <info> An arbitrary pointer passed to <<get_variable>>.
+    [RETURNS] TRUE on success, else FALSE.
+*/
+{
+	char ch;
+	unsigned int len;
+	unsigned int out_pos = 0;
+	const char *env;
+	const char *ptr;
+	struct passwd *pwent;
+	char buffer[BUFFER_SIZE], tmp[STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "st_expr_expand()\n");
+#endif
+
+	if (length > BUFFER_SIZE)
+		length = BUFFER_SIZE;
+	for (; TRUE; ++input)
+	{
+		switch (ch = *input)
+		{
+			case '$':
+				/*  Variable expansion  */
+				input = expand_variable (buffer, length, &out_pos, ++input, get_variable_func, info);
+				if (input == NULL)
+					return (FALSE);
+				break;
+			case '~':
+				/*  Home directory expansion  */
+				ch = input[1];
+				if ( isspace (ch) || (ch == '/') || (ch == '\0') )
+				{
+					/* User's own home directory: leave separator for next time */
+					if ( ( env = getenv ("HOME") ) == NULL )
+					{
+#ifdef CONFIG_DEVFSD_VERBOSE
+						msg_logger( NO_DIE, LOG_INFO, bb_msg_variable_not_found, "HOME");
+#endif
+						return (FALSE);
+					}
+					len = strlen (env);
+					if (len + out_pos >= length)
+						goto st_expr_expand_out;
+					memcpy (buffer + out_pos, env, len + 1);
+					out_pos += len;
+					continue;
+				}
+				/*  Someone else's home directory  */
+				for (ptr = ++input; !isspace (ch) && (ch != '/') && (ch != '\0'); ch = *++ptr)
+					/* VOID */ ;
+				len = ptr - input;
+				if (len >= sizeof tmp)
+					goto st_expr_expand_out;
+				safe_memcpy (tmp, input, len);
+				input = ptr - 1;
+				if ( ( pwent = getpwnam (tmp) ) == NULL )
+				{
+#ifdef CONFIG_DEVFSD_VERBOSE
+					msg_logger( NO_DIE, LOG_INFO, "getpwnam(): %s\n", tmp);
+#endif
+					return (FALSE);
+				}
+				len = strlen (pwent->pw_dir);
+				if (len + out_pos >= length)
+					goto st_expr_expand_out;
+				memcpy (buffer + out_pos, pwent->pw_dir, len + 1);
+				out_pos += len;
+				break;
+			case '\0':
+			/* Falltrough */
+			default:
+				if (out_pos >= length)
+					goto st_expr_expand_out;
+				buffer[out_pos++] = ch;
+				if (ch == '\0')
+				{
+					memcpy (output, buffer, out_pos);
+					return (TRUE);
+				}
+				break;
+			/* esac */
+		}
+	}
+	return (FALSE);
+st_expr_expand_out:
+#ifdef CONFIG_DEVFSD_VERBOSE
+	msg_logger( NO_DIE, LOG_INFO, bb_msg_small_buffer);
+#endif
+	return (FALSE);
+}   /*  End Function st_expr_expand  */
+
+
+/*  Private functions follow  */
+
+static const char *expand_variable (char *buffer, unsigned int length,
+				    unsigned int *out_pos, const char *input,
+				    const char *(*func) (const char *variable,
+							 void *info),
+				    void *info)
+/*  [SUMMARY] Expand a variable.
+    <buffer> The buffer to write to.
+    <length> The length of the output buffer.
+    <out_pos> The current output position. This is updated.
+    <input> A pointer to the input character pointer.
+    <func> A function which will be used to get variable values. If this
+    returns NULL, the environment is searched instead. If this is NULL, only
+    the environment is searched.
+    <info> An arbitrary pointer passed to <<func>>.
+    <errfp> Diagnostic messages are written here.
+    [RETURNS] A pointer to the end of this subexpression on success, else NULL.
+*/
+{
+	char ch;
+	int len;
+	unsigned int open_braces;
+	const char *env, *ptr;
+	char tmp[STRING_LENGTH];
+
+#ifdef CONFIG_DEVFSD_DEBUG
+	msg_logger( NO_DIE, LOG_INFO, "expand_variable()\n");
+#endif
+
+	ch = input[0];
+	if (ch == '$')
+	{
+		/*  Special case for "$$": PID  */
+		sprintf ( tmp, "%d", (int) getpid () );
+		len = strlen (tmp);
+		if (len + *out_pos >= length)
+			goto expand_variable_out;
+
+		memcpy (buffer + *out_pos, tmp, len + 1);
+		out_pos += len;
+		return (input);
+	}
+	/*  Ordinary variable expansion, possibly in braces  */
+	if (ch != '{')
+	{
+		/*  Simple variable expansion  */
+		for (ptr = input; isalnum (ch) || (ch == '_') || (ch == ':');ch = *++ptr)
+			/* VOID */ ;
+		len = ptr - input;
+		if (len >= sizeof tmp)
+			goto expand_variable_out;
+
+		safe_memcpy (tmp, input, len);
+		input = ptr - 1;
+		if ( ( env = get_variable_v2 (tmp, func, info) ) == NULL )
+		{
+#ifdef CONFIG_DEVFSD_VERBOSE
+			msg_logger( NO_DIE, LOG_INFO, bb_msg_variable_not_found, tmp);
+#endif
+			return (NULL);
+		}
+		len = strlen (env);
+		if (len + *out_pos >= length)
+			goto expand_variable_out;
+
+		memcpy (buffer + *out_pos, env, len + 1);
+		*out_pos += len;
+		return (input);
+	}
+	/*  Variable in braces: check for ':' tricks  */
+	ch = *++input;
+	for (ptr = input; isalnum (ch) || (ch == '_'); ch = *++ptr)
+		/* VOID */;
+	if (ch == '}')
+	{
+		/*  Must be simple variable expansion with "${var}"  */
+		len = ptr - input;
+		if (len >= sizeof tmp)
+			goto expand_variable_out;
+
+		safe_memcpy (tmp, input, len);
+		ptr = expand_variable (buffer, length, out_pos, tmp, func, info );
+		if (ptr == NULL)
+			return (NULL);
+		return (input + len);
+	}
+	if (ch != ':' || ptr[1] != '-' )
+	{
+#ifdef CONFIG_DEVFSD_VERBOSE
+		msg_logger( NO_DIE, LOG_INFO,"illegal char in var name\n");
+#endif
+		return (NULL);
+	}
+	/*  It's that handy "${var:-word}" expression. Check if var is defined  */
+	len = ptr - input;
+	if (len >= sizeof tmp)
+		goto expand_variable_out;
+
+	safe_memcpy (tmp, input, len);
+	/*  Move input pointer to ':'  */
+	input = ptr;
+	/*  First skip to closing brace, taking note of nested expressions  */
+	ptr += 2;
+	ch = ptr[0];
+	for (open_braces = 1; open_braces > 0; ch = *++ptr)
+	{
+		switch (ch)
+		{
+			case '{':
+				++open_braces;
+				break;
+			case '}':
+				--open_braces;
+				break;
+			case '\0':
+#ifdef CONFIG_DEVFSD_VERBOSE
+				msg_logger( NO_DIE, LOG_INFO,"\"}\" not found in: %s\n", input);
+#endif
+				return (NULL);
+			default:
+				break;
+		}
+	}
+	--ptr;
+	/*  At this point ptr should point to closing brace of "${var:-word}"  */
+	if ( ( env = get_variable_v2 (tmp, func, info) ) != NULL )
+	{
+		/*  Found environment variable, so skip the input to the closing brace
+			and return the variable  */
+		input = ptr;
+		len = strlen (env);
+		if (len + *out_pos >= length)
+			goto expand_variable_out;
+
+		memcpy (buffer + *out_pos, env, len + 1);
+		*out_pos += len;
+		return (input);
+	}
+	/*  Environment variable was not found, so process word. Advance input
+	pointer to start of word in "${var:-word}"  */
+	input += 2;
+	len = ptr - input;
+	if (len >= sizeof tmp)
+		goto expand_variable_out;
+
+	safe_memcpy (tmp, input, len);
+	input = ptr;
+	if ( !st_expr_expand (tmp, STRING_LENGTH, tmp, func, info ) )
+		return (NULL);
+	len = strlen (tmp);
+	if (len + *out_pos >= length)
+		goto expand_variable_out;
+
+	memcpy (buffer + *out_pos, tmp, len + 1);
+	*out_pos += len;
+	return (input);
+expand_variable_out:
+#ifdef CONFIG_DEVFSD_VERBOSE
+	msg_logger( NO_DIE, LOG_INFO, bb_msg_small_buffer);
+#endif
+	return (NULL);
+}   /*  End Function expand_variable  */
+
+
+static const char *get_variable_v2 (const char *variable,
+				  const char *(*func) (const char *variable, void *info),
+				 void *info)
+/*  [SUMMARY] Get a variable from the environment or .
+    <variable> The variable name.
+    <func> A function which will be used to get the variable. If this returns
+    NULL, the environment is searched instead. If this is NULL, only the
+    environment is searched.
+    [RETURNS] The value of the variable on success, else NULL.
+*/
+{
+	const char *value;
+
+#ifdef CONFIG_DEVFSD_DEBUG
+		msg_logger( NO_DIE, LOG_INFO, "get_variable_v2()\n");
+#endif
+
+	if (func != NULL)
+	{
+		value = (*func) (variable, info);
+		if (value != NULL)
+			return (value);
+	}
+	return getenv (variable);
+}   /*  End Function get_variable  */
+
+/* END OF CODE */