text: /* vi: set sw=4 ts=4: */
  /*
   * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
   */
  
  /*
  	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 <sys/wait.h>
  //#include <sys/ioctl.h>
  //#include <sys/socket.h>
  #include <sys/un.h>
  #include <dirent.h>
  #include <syslog.h>
  #include <sys/sysmacros.h>
  #include "libbb.h"
  #include "xregex.h"
  
  
  /* Various defines taken from linux/major.h */
  #define IDE0_MAJOR	3
  #define IDE1_MAJOR	22
  #define IDE2_MAJOR	33
  #define IDE3_MAJOR	34
  #define IDE4_MAJOR	56
  #define IDE5_MAJOR	57
  #define IDE6_MAJOR	88
  #define IDE7_MAJOR	89
  #define IDE8_MAJOR	90
  #define IDE9_MAJOR	91
  
  
  /* Various defines taken from linux/devfs_fs.h */
  #define DEVFSD_PROTOCOL_REVISION_KERNEL  5
  #define	DEVFSD_IOCTL_BASE	'd'
  /*  These are the various ioctls  */
  #define DEVFSDIOC_GET_PROTO_REV         _IOR(DEVFSD_IOCTL_BASE, 0, int)
  #define DEVFSDIOC_SET_EVENT_MASK        _IOW(DEVFSD_IOCTL_BASE, 2, int)
  #define DEVFSDIOC_RELEASE_EVENT_QUEUE   _IOW(DEVFSD_IOCTL_BASE, 3, int)
  #define DEVFSDIOC_SET_CONFIG_DEBUG_MASK _IOW(DEVFSD_IOCTL_BASE, 4, int)
  #define DEVFSD_NOTIFY_REGISTERED    0
  #define DEVFSD_NOTIFY_UNREGISTERED  1
  #define DEVFSD_NOTIFY_ASYNC_OPEN    2
  #define DEVFSD_NOTIFY_CLOSE         3
  #define DEVFSD_NOTIFY_LOOKUP        4
  #define DEVFSD_NOTIFY_CHANGE        5
  #define DEVFSD_NOTIFY_CREATE        6
  #define DEVFSD_NOTIFY_DELETE        7
  #define DEVFS_PATHLEN               1024
  /*  Never change this otherwise the binary interface will change   */
  
  struct devfsd_notify_struct
  {   /*  Use native C types to ensure same types in kernel and user space     */
      unsigned int type;           /*  DEVFSD_NOTIFY_* value                   */
      unsigned int mode;           /*  Mode of the inode or device entry       */
      unsigned int major;          /*  Major number of device entry            */
      unsigned int minor;          /*  Minor number of device entry            */
      unsigned int uid;            /*  Uid of process, inode or device entry   */
      unsigned int gid;            /*  Gid of process, inode or device entry   */
      unsigned int overrun_count;  /*  Number of lost events                   */
      unsigned int namelen;        /*  Number of characters not including '\0' */
      /*  The device name MUST come last                                       */
      char devname[DEVFS_PATHLEN]; /*  This will be '\0' terminated            */
  };
  
  #define BUFFER_SIZE 16384
  #define DEVFSD_VERSION "1.3.25"
  #define CONFIG_FILE  "/etc/devfsd.conf"
  #define MODPROBE		"/sbin/modprobe"
  #define MODPROBE_SWITCH_1 "-k"
  #define MODPROBE_SWITCH_2 "-C"
  #define CONFIG_MODULES_DEVFS "/etc/modules.devfs"
  #define MAX_ARGS     (6 + 1)
  #define MAX_SUBEXPR  10
  #define STRING_LENGTH 255
  
  /* for get_uid_gid() */
  #define UID			0
  #define GID			1
  
  /* fork_and_execute() */
  # define DIE			1
  # define NO_DIE			0
  
  /* for dir_operation() */
  #define RESTORE		0
  #define SERVICE		1
  #define READ_CONFIG 2
  
  /*  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
  #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 void dir_operation(int , const char * , int,  unsigned long*);
  static void service(struct stat statbuf, char *path);
  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(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_modload(const struct devfsd_notify_struct *info, const struct config_entry_struct *entry);
  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 restore(char *spath, struct stat source_stat, int rootlen);
  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 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, const char *);
  
  /* busybox functions */
  static int get_uid_gid(int flag, const char *string);
  static void safe_memcpy(char * dest, const char * src, int len);
  static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr);
  static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr);
  
  /* Structs and vars */
  static struct config_entry_struct *first_config = NULL;
  static struct config_entry_struct *last_config = NULL;
  static char *mount_point = NULL;
  static volatile int caught_signal = FALSE;
  static volatile int caught_sighup = FALSE;
  static struct initial_symlink_struct {
  	const char *dest;
  	const 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 messages */
  
  static const char bb_msg_proto_rev[] ALIGN1          = "protocol revision";
  static const char bb_msg_bad_config[] ALIGN1         = "bad %s config file: %s";
  static const char bb_msg_small_buffer[] ALIGN1       = "buffer too small";
  static const char bb_msg_variable_not_found[] ALIGN1 = "variable: %s not found";
  
  /* Busybox stuff */
  #if ENABLE_DEVFSD_VERBOSE || ENABLE_DEBUG
  #define info_logger(p, fmt, args...)                 bb_info_msg(fmt, ## args)
  #define msg_logger(p, fmt, args...)                  bb_error_msg(fmt, ## args)
  #define msg_logger_and_die(p, fmt, args...)          bb_error_msg_and_die(fmt, ## args)
  #define error_logger(p, fmt, args...)                bb_perror_msg(fmt, ## args)
  #define error_logger_and_die(p, fmt, args...)        bb_perror_msg_and_die(fmt, ## args)
  #else
  #define info_logger(p, fmt, args...)
  #define msg_logger(p, fmt, args...)
  #define msg_logger_and_die(p, fmt, args...)           exit(1)
  #define error_logger(p, fmt, args...)
  #define error_logger_and_die(p, fmt, args...)         exit(1)
  #endif
  
  static void safe_memcpy(char *dest, const char *src, int len)
  {
  	memcpy(dest , src, len);
  	dest[len] = '\0';
  }
  
  static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr)
  {
  	if (d[n - 4] == 'd' && d[n - 3] == 'i' && d[n - 2] == 's' && d[n - 1] == 'c')
  		return 2 + addendum;
  	if (d[n - 2] == 'c' && d[n - 1] == 'd')
  		return 3 + addendum;
  	if (ptr[0] == 'p' && ptr[1] == 'a' && ptr[2] == 'r' && ptr[3] == 't')
  		return 4 + addendum;
  	if (ptr[n - 2] == 'm' && ptr[n - 1] == 't')
  		return 5 + addendum;
  	return 0;
  }
  
  static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr)
  {
  	if (d[0] == 's' && d[1] == 'c' && d[2] == 's' && d[3] == 'i' && d[4] == '/') {
  		if (d[n - 7] == 'g' && d[n - 6] == 'e' && d[n - 5] == 'n'
  			&& d[n - 4] == 'e' && d[n - 3] == 'r' && d[n - 2] == 'i' && d[n - 1] == 'c'
  		)
  			return 1;
  		return scan_dev_name_common(d, n, 0, ptr);
  	}
  	if (d[0] == 'i' && d[1] == 'd' && d[2] == 'e' && d[3] == '/'
  		&& d[4] == 'h' && d[5] == 'o' && d[6] == 's' && d[7] == 't'
  	)
  		return scan_dev_name_common(d, n, 4, ptr);
  	if (d[0] == 's' && d[1] == 'b' && d[2] == 'p' && d[3] == '/')
  		return 10;
  	if (d[0] == 'v' && d[1] == 'c' && d[2] == 'c' && d[3] == '/')
  		return 11;
  	if (d[0] == 'p' && d[1] == 't' && d[2] == 'y' && d[3] == '/')
  		return 12;
  	return 0;
  }
  
  /*  Public functions follow  */
  
  int devfsd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  int devfsd_main(int argc, char **argv)
  {
  	int print_version = FALSE;
  	int do_daemon = TRUE;
  	int no_polling = FALSE;
  	int do_scan;
  	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 (argv[count][0] == '-') {
  			if (argv[count][1] == 'v' && !argv[count][2]) /* -v */
  				print_version = TRUE;
  			else if (ENABLE_DEVFSD_FG_NP && argv[count][1] == 'f'
  			 && argv[count][2] == 'g' && !argv[count][3]) /* -fg */
  				do_daemon = FALSE;
  			else if (ENABLE_DEVFSD_FG_NP && argv[count][1] == 'n'
  			 && argv[count][2] == 'p' && !argv[count][3]) /* -np */
  				no_polling = TRUE;
  			else
  				bb_show_usage();
  		}
  	}
  
  	mount_point = bb_simplify_path(argv[1]);
  
  	xchdir(mount_point);
  
  	fd = xopen(".devfsd", O_RDONLY);
  	close_on_exec_on(fd);
  	xioctl(fd, DEVFSDIOC_GET_PROTO_REV, &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)) {
  		printf("%s v%s\nDaemon %s:\t%d\nKernel-side %s:\t%d\n",
  				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)  */
  	xioctl(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");
  
  	printf("%s v%s  started for %s\n",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((char*)CONFIG_FILE, FALSE, &event_mask);
  	/*  Do the scan before forking, so that boot scripts see the finished product  */
  	dir_operation(SERVICE, mount_point, 0, NULL);
  
  	if (ENABLE_DEVFSD_FG_NP && no_polling)
  		exit(0);
  
  	if (ENABLE_DEVFSD_VERBOSE || ENABLE_DEBUG)
  		logmode = LOGMODE_BOTH;
  	else if (do_daemon == TRUE)
  		logmode = LOGMODE_SYSLOG;
  	/* This is the default */
  	/*else
  		logmode = LOGMODE_STDIO; */
  
  	if (do_daemon) {
  		/*  Release so that the child can grab it  */
  		xioctl(fd, DEVFSDIOC_RELEASE_EVENT_QUEUE, 0);
  		bb_daemonize_or_rexec(0, argv);
  	} else if (ENABLE_DEVFSD_FG_NP) {
  		setpgid(0, 0);  /*  Become process group leader                    */
  	}
  
  	while (TRUE) {
  		do_scan = do_servicing(fd, event_mask);
  
  		free_config();
  		read_config_file((char*)CONFIG_FILE, FALSE, &event_mask);
  		if (do_scan)
  			dir_operation(SERVICE, mount_point, 0, NULL);
  	}
  	if (ENABLE_FEATURE_CLEAN_UP) free(mount_point);
  }   /*  End Function main  */
  
  
  /*  Private functions follow  */
  
  static void read_config_file(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];
  	char *line = NULL;
  	char *p;
  
  	if (stat(path, &statbuf) == 0) {
  		/* Don't read 0 length files: ignored */
  		/*if (statbuf.st_size == 0)
  				return;*/
  		if (S_ISDIR(statbuf.st_mode)) {
  			p = bb_simplify_path(path);
  			dir_operation(READ_CONFIG, p, 0, event_mask);
  			free(p);
  			return;
  		}
  		if ((fp = fopen(path, "r")) != NULL) {
  			while (fgets(buf, STRING_LENGTH, fp) != NULL) {
  				/*  Skip whitespace  */
  				line = buf;
  				line = skip_whitespace(line);
  				if (line[0] == '\0' || line[0] == '#')
  					continue;
  				process_config_line(line, event_mask);
  			}
  			fclose(fp);
  		} else {
  			goto read_config_file_err;
  		}
  	} else {
  read_config_file_err:
  		if (optional == 0 && errno == ENOENT)
  			error_logger_and_die(LOG_ERR, "read config file: %s", 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];
  	const char *msg = "";
  	char *ptr;
  	int i;
  
  	/* !!!! Only Uppercase Keywords in devsfd.conf */
  	static const char options[] ALIGN1 =
  		"CLEAR_CONFIG\0""INCLUDE\0""OPTIONAL_INCLUDE\0"
  		"RESTORE\0""PERMISSIONS\0""MODLOAD\0""EXECUTE\0"
  		"COPY\0""IGNORE\0""MKOLDCOMPAT\0""MKNEWCOMPAT\0"
  		"RMOLDCOMPAT\0""RMNEWCOMPAT\0";
  
  	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]);
  
  	i = index_in_strings(options, when);
  
  	/* "CLEAR_CONFIG" */
  	if (i == 0) {
  		free_config();
  		*event_mask = 0;
  		return;
  	}
  
  	if (num_args < 2)
  		goto process_config_line_err;
  
  	/* "INCLUDE" & "OPTIONAL_INCLUDE" */
  	if (i == 1 || i == 2) {
  		st_expr_expand(name, STRING_LENGTH, name, get_variable, NULL);
  		info_logger(LOG_INFO, "%sinclude: %s", (toupper(when[0]) == 'I') ? "": "optional_", name);
  		read_config_file(name, (toupper(when[0]) == 'I') ? FALSE : TRUE, event_mask);
  		return;
  	}
  	/* "RESTORE" */
  	if (i == 3) {
  		dir_operation(RESTORE, name, strlen(name),NULL);
  		return;
  	}
  	if (num_args < 3)
  		goto process_config_line_err;
  
  	new = xzalloc(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;
  	}
  
  	i = index_in_strings(options, what);
  
  	switch (i) {
  		case 4:	/* "PERMISSIONS" */
  			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]);
  			break;
  		case 5:	/*  MODLOAD */
  			/*This  action will pass "/dev/$devname"(i.e. "/dev/" prefixed to
  			the device name) to the module loading  facility.  In  addition,
  			the /etc/modules.devfs configuration file is used.*/
  			 if (ENABLE_DEVFSD_MODLOAD)
  				new->action.what = AC_MODLOAD;
  			 break;
  		case 6: /* EXECUTE */
  			new->action.what = AC_EXECUTE;
  			num_args -= 3;
  
  			for (count = 0; count < num_args; ++count)
  				new->u.execute.argv[count] = xstrdup(p[count]);
  
  			new->u.execute.argv[num_args] = NULL;
  			break;
  		case 7: /* COPY */
  			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 = xstrdup(p[0]);
  			new->u.copy.destination = xstrdup(p[1]);
  			break;
  		case 8: /* IGNORE */
  		/* FALLTROUGH */
  		case 9: /* MKOLDCOMPAT */
  		/* FALLTROUGH */
  		case 10: /* MKNEWCOMPAT */
  		/* FALLTROUGH */
  		case 11:/* RMOLDCOMPAT */
  		/* FALLTROUGH */
  		case 12: /* RMNEWCOMPAT */
  		/*	AC_IGNORE					6
  			AC_MKOLDCOMPAT				7
  			AC_MKNEWCOMPAT				8
  			AC_RMOLDCOMPAT				9
  			AC_RMNEWCOMPAT				10*/
  			new->action.what = i - 2;
  			break;
  		default:
  			msg = "WHAT in";
  			goto process_config_line_err;
  		/*esac*/
  	} /* switch (i) */
  
  	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_and_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;
  
  	/* (void*) cast is only in order to match prototype */
  	xioctl(fd, DEVFSDIOC_SET_EVENT_MASK, (void*)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;
  		service_name(&info);
  	}
  	if (caught_signal) {
  		int c_sighup = caught_sighup;
  
  		caught_signal = FALSE;
  		caught_sighup = FALSE;
  		return c_sighup;
  	}
  	msg_logger_and_die(LOG_ERR, "read error on control file");
  }   /*  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;
  
  	if (ENABLE_DEBUG && info->overrun_count > 0)
  		msg_logger(LOG_ERR, "lost %u events", info->overrun_count);
  
  	/*  Discard lookups on "/dev/log" and "/dev/initctl"  */
  	if (info->type == DEVFSD_NOTIFY_LOOKUP
  		&& ((info->devname[0] == 'l' && info->devname[1] == 'o'
  		&& info->devname[2] == 'g' && !info->devname[3])
  		|| (info->devname[0] == 'i' && info->devname[1] == 'n'
  		&& info->devname[2] == 'i' && info->devname[3] == 't'
  		&& info->devname[4] == 'c' && info->devname[5] == 't'
  		&& info->devname[6] == 'l' && !info->devname[7]))
  	)
  		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:
  				action_permissions(info, entry);
  				break;
  			case AC_MODLOAD:
  				if (ENABLE_DEVFSD_MODLOAD)
  					action_modload(info, entry);
  				break;
  			case AC_EXECUTE:
  				action_execute(info, entry, mbuf, n);
  				break;
  			case AC_COPY:
  				action_copy(info, entry, mbuf, n);
  				break;
  			case AC_IGNORE:
  				return;
  				/*break;*/
  			case AC_MKOLDCOMPAT:
  			case AC_MKNEWCOMPAT:
  			case AC_RMOLDCOMPAT:
  			case AC_RMNEWCOMPAT:
  				action_compat(info, entry->action.what);
  				break;
  			default:
  				msg_logger_and_die(LOG_ERR, "Unknown action");
  		}
  	}
  }   /*  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;
  
  	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
  	)
  		error_logger(LOG_ERR, "Can't chmod or chown: %s", info->devname);
  }   /*  End Function action_permissions  */
  
  static void action_modload(const struct devfsd_notify_struct *info,
  			    const struct config_entry_struct *entry ATTRIBUTE_UNUSED)
  /*  [SUMMARY] Load a module.
      <info> The devfs change.
      <entry> The config file entry.
      [RETURNS] Nothing.
  */
  {
  	char *argv[6];
  
  	argv[0] = (char*)MODPROBE;
  	argv[1] = (char*)MODPROBE_SWITCH_1; /* "-k" */
  	argv[2] = (char*)MODPROBE_SWITCH_2; /* "-C" */
  	argv[3] = (char*)CONFIG_MODULES_DEVFS;
  	argv[4] = concat_path_file("/dev", info->devname); /* device */
  	argv[5] = NULL;
  
  	wait4pid(xspawn(argv));
  	free(argv[4]);
  }  /*  End Function action_modload  */
  
  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];
  
  	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;
  	wait4pid(spawn(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];
  	int ret = 0;
  
  	dest_stat.st_mode = 0;
  
  	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)
  			return;
  	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;
  	ret = copy_inode(destination, &dest_stat, new_mode, source, &source_stat);
  	if (ENABLE_DEBUG && ret && (errno != EEXIST))
  		error_logger(LOG_ERR, "copy_inode: %s to %s", source, destination);
  }   /*  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.
  */
  {
  	int ret;
  	const char *compat_name = NULL;
  	const char *dest_name = info->devname;
  	const char *ptr;
  	char compat_buf[STRING_LENGTH], dest_buf[STRING_LENGTH];
  	int mode, host, bus, target, lun;
  	unsigned int i;
  	char rewind_;
  	/* 1 to 5  "scsi/" , 6 to 9 "ide/host" */
  	static const char *const fmt[] = {
  		NULL ,
  		"sg/c%db%dt%du%d",		/* scsi/generic */
  		"sd/c%db%dt%du%d",		/* scsi/disc */
  		"sr/c%db%dt%du%d",		/* scsi/cd */
  		"sd/c%db%dt%du%dp%d",		/* scsi/part */
  		"st/c%db%dt%du%dm%d%c",		/* scsi/mt */
  		"ide/hd/c%db%dt%du%d",		/* ide/host/disc */
  		"ide/cd/c%db%dt%du%d",		/* ide/host/cd */
  		"ide/hd/c%db%dt%du%dp%d",	/* ide/host/part */
  		"ide/mt/c%db%dt%du%d%s",	/* ide/host/mt */
  		NULL
  	};
  
  	/*  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:
  			ptr = bb_basename(info->devname);
  			i = scan_dev_name(info->devname, info->namelen, ptr);
  
  			/* nothing found */
  			if (i == 0 || i > 9)
  				return;
  
  			sscanf(info->devname + ((i < 6) ? 5 : 4), "host%d/bus%d/target%d/lun%d/", &host, &bus, &target, &lun);
  			snprintf(dest_buf, sizeof(dest_buf), "../%s", info->devname + (( i > 5) ? 4 : 0));
  			dest_name = dest_buf;
  			compat_name = compat_buf;
  
  
  			/* 1 == scsi/generic  2 == scsi/disc 3 == scsi/cd 6 == ide/host/disc 7 == ide/host/cd */
  			if (i == 1 || i == 2 || i == 3 || i == 6 || i ==7)
  				sprintf(compat_buf, fmt[i], host, bus, target, lun);
  
  			/* 4 == scsi/part 8 == ide/host/part */
  			if (i == 4 || i == 8)
  				sprintf(compat_buf, fmt[i], host, bus, target, lun, atoi(ptr + 4));
  
  			/* 5 == scsi/mt */
  			if (i == 5) {
  				rewind_ = info->devname[info->namelen - 1];
  				if (rewind_ != 'n')
  					rewind_ = '\0';
  				mode=0;
  				if (ptr[2] ==  'l' /*108*/ || ptr[2] == 'm'/*109*/)
  					mode = ptr[2] - 107; /* 1 or 2 */
  				if (ptr[2] ==  'a')
  					mode = 3;
  				sprintf(compat_buf, fmt[i], host, bus, target, lun, mode, rewind_);
  			}
  
  			/* 9 == ide/host/mt */
  			if (i ==  9)
  				snprintf(compat_buf, sizeof(compat_buf), fmt[i], host, bus, target, lun, ptr + 2);
  		/* esac */
  	} /* switch (action) */
  
  	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:
  			ret = unlink(compat_name);
  			if (ENABLE_DEBUG && ret)
  				error_logger(LOG_ERR, "unlink: %s", compat_name);
  			break;
  		/*esac*/
  	} /* switch (action) */
  }   /*  End Function action_compat  */
  
  static void restore(char *spath, struct stat source_stat, int rootlen)
  {
  	char *dpath;
  	struct stat dest_stat;
  
  	dest_stat.st_mode = 0;
  	dpath = concat_path_file(mount_point, spath + rootlen);
  	lstat(dpath, &dest_stat);
  	free(dpath);
  	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))
  		dir_operation(RESTORE, spath, rootlen,NULL);
  }
  
  
  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.
  */
  {
  	int source_len, dest_len;
  	char source_link[STRING_LENGTH], dest_link[STRING_LENGTH];
  	int fd, val;
  	struct sockaddr_un un_addr;
  	char symlink_val[STRING_LENGTH];
  
  	if ((source_stat->st_mode & S_IFMT) ==(dest_stat->st_mode & S_IFMT)) {
  		/*  Same type  */
  		if (S_ISLNK(source_stat->st_mode)) {
  			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) {
  		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;
  			goto do_chown;
  		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;
  			goto do_chown;
  		case S_IFBLK:
  		case S_IFCHR:
  		case S_IFIFO:
  			if (mknod(destpath, new_mode, source_stat->st_rdev) != 0)
  				break;
  			goto do_chown;
  		case S_IFDIR:
  			if (mkdir(destpath, new_mode & ~S_IFMT) != 0)
  				break;
  do_chown:
  			if (chown(destpath, source_stat->st_uid, source_stat->st_gid) == 0)
  				return TRUE;
  		/*break;*/
  	}
  	return FALSE;
  }   /*  End Function copy_inode  */
  
  static void free_config(void)
  /*  [SUMMARY] Free the configuration information.
      [RETURNS] Nothing.
  */
  {
  	struct config_entry_struct *c_entry;
  	void *next;
  
  	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;
  	static const char *msg;
  
  	if (ENABLE_DEVFSD_VERBOSE)
  		msg = "user";
  
  	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 if (ENABLE_DEVFSD_VERBOSE)
  		msg = "group";
  
  	if (ENABLE_DEVFSD_VERBOSE)
  		msg_logger(LOG_ERR,"unknown %s: %s, defaulting to %cid=0",  msg, string, msg[0]);
  	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;
  	int i;
  
  	if (isdigit(string[0]))
  		return strtoul(string, NULL, 8);
  	if (strlen(string) != 9)
  		msg_logger_and_die(LOG_ERR, "bad mode: %s", string);
  
  	mode = 0;
  	i = S_IRUSR;
  	while (i > 0) {
  		if (string[0] == 'r' || string[0] == 'w' || string[0] == 'x')
  			mode += i;
  		i = i / 2;
  		string++;
  	}
  	return mode;
  }   /*  End Function get_mode  */
  
  static void signal_handler(int sig)
  {
  	caught_signal = TRUE;
  	if (sig == SIGHUP)
  		caught_sighup = TRUE;
  
  	info_logger(LOG_INFO, "Caught signal %d", sig);
  }   /*  End Function signal_handler  */
  
  static const char *get_variable(const char *variable, void *info)
  {
  	static char sbuf[sizeof(int)*3 + 2]; /* sign and NUL */
  
  	char hostname[STRING_LENGTH];
  	struct get_variable_info *gv_info = info;
  	const char *field_names[] = {
  			"hostname", "mntpt", "devpath", "devname",
  			"uid", "gid", "mode", hostname, mount_point,
  			gv_info->devpath, gv_info->devname, NULL
  	};
  	int i;
  
  	if (gethostname(hostname, STRING_LENGTH - 1) != 0)
  		/* Here on error we should do exit(RV_SYS_ERROR), instead we do exit(EXIT_FAILURE) */
  		error_logger_and_die(LOG_ERR, "gethostname");
  
  	hostname[STRING_LENGTH - 1] = '\0';
  
  	/* index_in_str_array returns i>=0  */
  	i = index_in_str_array(field_names, variable);
  
  	if (i > 6 || i < 0 || (i > 1 && gv_info == NULL))
  		return NULL;
  	if (i >= 0 && i <= 3)
  		return field_names[i + 7];
  
  	if (i == 4)
  		sprintf(sbuf, "%u", gv_info->info->uid);
  	else if (i == 5)
  		sprintf(sbuf, "%u", gv_info->info->gid);
  	else if (i == 6)
  		sprintf(sbuf, "%o", gv_info->info->mode);
  	return sbuf;
  }   /*  End Function get_variable  */
  
  static void service(struct stat statbuf, char *path)
  {
  	struct devfsd_notify_struct info;
  
  	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))
  		dir_operation(SERVICE, path, 0, NULL);
  }
  
  static void dir_operation(int type, const char * dir_name, int var, unsigned long *event_mask)
  /*  [SUMMARY] Scan a directory tree and generate register events on leaf nodes.
  	<flag> To choose which function to perform
  	<dp> The directory pointer. This is closed upon completion.
      <dir_name> The name of the directory.
  	<rootlen> string length parameter.
      [RETURNS] Nothing.
  */
  {
  	struct stat statbuf;
  	DIR *dp;
  	struct dirent *de;
  	char *path;
  
  	if ((dp = warn_opendir(dir_name)) == NULL)
  		return;
  
  	while ((de = readdir(dp)) != NULL) {
  
  		if (de->d_name && DOT_OR_DOTDOT(de->d_name))
  			continue;
  		path = concat_path_file(dir_name, de->d_name);
  		if (lstat(path, &statbuf) == 0) {
  			switch (type) {
  				case SERVICE:
  					service(statbuf, path);
  					break;
  				case RESTORE:
  					restore(path, statbuf, var);
  					break;
  				case READ_CONFIG:
  					read_config_file(path, var, event_mask);
  					break;
  			}
  		}
  		free(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.
  */
  {
  	if (!make_dir_tree(newpath))
  		return -1;
  
  	if (symlink(oldpath, newpath) != 0) {
  		if (errno != EEXIST)
  			return -1;
  	}
  	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 the leaf node).
      [RETURNS] TRUE on success, else FALSE.
  */
  {
  	if (bb_make_directory(dirname((char *)path), -1, FILEUTILS_RECUR) == -1)
  		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 environment 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];
  
  	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;
  
  	/*  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
  {
  	const char *match;    /*  The string to match to(up to length)                */
  	const 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;
  	const char *ptr;
  	struct translate_struct *trans;
  	unsigned int i;
  	char mode;
  	int indexx;
  	const char *pty1;
  	const char *pty2;
  	size_t len;
  	/* 1 to 5  "scsi/" , 6 to 9 "ide/host", 10 sbp/, 11 vcc/, 12 pty/ */
  	static const char *const fmt[] = {
  		NULL ,
  		"sg%u",			/* scsi/generic */
  		NULL,			/* scsi/disc */
  		"sr%u",			/* scsi/cd */
  		NULL,			/* scsi/part */
  		"nst%u%c",		/* scsi/mt */
  		"hd%c"	,		/* ide/host/disc */
  		"hd%c"	,		/* ide/host/cd */
  		"hd%c%s",		/* ide/host/part */
  		"%sht%d",		/* ide/host/mt */
  		"sbpcd%u",		/* sbp/ */
  		"vcs%s",		/* vcc/ */
  		"%cty%c%c",		/* pty/ */
  		NULL
  	};
  
  	for (trans = translate_table; trans->match != NULL; ++trans) {
  		 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;
  		}
  	}
  
  	ptr = bb_basename(devname);
  	i = scan_dev_name(devname, namelen, ptr);
  
  	if (i > 0 && i < 13)
  		compat_name = buffer;
  	else
  		return NULL;
  
  	/* 1 == scsi/generic, 3 == scsi/cd, 10 == sbp/ */
  	if (i == 1 || i == 3 || i == 10)
  		sprintf(buffer, fmt[i], minor);
  
  	/* 2 ==scsi/disc, 4 == scsi/part */
  	if (i == 2 || i == 4)
  		compat_name = write_old_sd_name(buffer, major, minor,((i == 2) ? "" : (ptr + 4)));
  
  	/* 5 == scsi/mt */
  	if (i == 5) {
  		mode = ptr[2];
  		if (mode == 'n')
  			mode = '\0';
  		sprintf(buffer, fmt[i], minor & 0x1f, mode);
  		if (devname[namelen - 1] != 'n')
  			++compat_name;
  	}
  	/* 6 == ide/host/disc, 7 == ide/host/cd, 8 == ide/host/part */
  	if (i == 6 || i == 7 || i == 8)
  		/* last arg should be ignored for i == 6 or i== 7 */
  		sprintf(buffer, fmt[i] , get_old_ide_name(major, minor), ptr + 4);
  
  	/* 9 ==  ide/host/mt */
  	if (i == 9)
  		sprintf(buffer, fmt[i], ptr + 2, minor & 0x7f);
  
  	/*  11 == vcc/ */
  	if (i == 11) {
  		sprintf(buffer, fmt[i], devname + 4);
  		if (buffer[3] == '0')
  			buffer[3] = '\0';
  	}
  	/* 12 ==  pty/ */
  	if (i == 12) {
  		pty1 = "pqrstuvwxyzabcde";
  		pty2 = "0123456789abcdef";
  		indexx = atoi(devname + 5);
  		sprintf(buffer, fmt[i], (devname[4] == 'm') ? 'p' : 't', pty1[indexx >> 4], pty2[indexx & 0x0f]);
  	}
  	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;
  
  	/* 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 ((unsigned int)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,
  				const 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;
  
  	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];
  
  	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) {
  						info_logger(LOG_INFO, bb_msg_variable_not_found, "HOME");
  						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) {
  					info_logger(LOG_INFO, "no pwent for: %s", tmp);
  					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:
  	info_logger(LOG_INFO, bb_msg_small_buffer);
  	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];
  
  	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 ((size_t)len >= sizeof tmp)
  			goto expand_variable_out;
  
  		safe_memcpy(tmp, input, len);
  		input = ptr - 1;
  		if ((env = get_variable_v2(tmp, func, info)) == NULL) {
  			info_logger(LOG_INFO, bb_msg_variable_not_found, tmp);
  			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 ((size_t)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] != '-') {
  		info_logger(LOG_INFO, "illegal char in var name");
  		return NULL;
  	}
  	/*  It's that handy "${var:-word}" expression. Check if var is defined  */
  	len = ptr - input;
  	if ((size_t)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':
  				info_logger(LOG_INFO,"\"}\" not found in: %s", input);
  				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 ((size_t)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:
  	info_logger(LOG_INFO, bb_msg_small_buffer);
  	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;
  
  	if (func != NULL) {
  		value = (*func)(variable, info);
  		if (value != NULL)
  			return value;
  	}
  	return getenv(variable);
  }   /*  End Function get_variable  */
  
  /* END OF CODE */
  