modutils/modprobe.c - fp2-dev/platform/external/busybox - Gitiles

 /* vi: set sw=4 ts=4: */
 /*
  * Modprobe written from scratch for BusyBox
  *
  * Copyright (c) 2002 by Robert Griebl, griebl@gmx.de
  * Copyright (c) 2003 by Andrew Dennison, andrew.dennison@motec.com.au
  *
  * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  *
 */

 #include <sys/utsname.h>
 #include <getopt.h>
 #include <stdlib.h>
 #include <unistd.h>
 #include <syslog.h>
 #include <string.h>
 #include <ctype.h>
 #include <fcntl.h>
 #include "busybox.h"


 struct dep_t {
 	char *  m_module;
 	char *  m_options;

 	int     m_isalias  : 1;
 	int     m_reserved : 15;

 	int     m_depcnt   : 16;
 	char ** m_deparr;

 	struct dep_t * m_next;
 };

 struct mod_list_t {
 	char *  m_module;
 	char *  m_options;

 	struct mod_list_t * m_prev;
 	struct mod_list_t * m_next;
 };


 static struct dep_t *depend;
 static int autoclean, show_only, quiet, do_syslog, verbose;

 int parse_tag_value ( char *buffer, char **ptag, char **pvalue )
 {
 	char *tag, *value;

 	while ( isspace ( *buffer ))
 		buffer++;
 	tag = value = buffer;
 	while ( !isspace ( *value ))
 		value++;
 	*value++ = 0;
 	while ( isspace ( *value ))
 		value++;

 	*ptag = tag;
 	*pvalue = value;

 	return bb_strlen( tag ) && bb_strlen( value );
 }

 /* Jump through hoops to simulate how fgets() grabs just one line at a
  * time... Don't use any stdio since modprobe gets called from a kernel
  * thread and stdio junk can overflow the limited stack...
  */
 static char *reads ( int fd, char *buffer, size_t len )
 {
 	int n = read ( fd, buffer, len );

 	if ( n > 0 ) {
 		char *p;

 		buffer [len-1] = 0;
 		p = strchr ( buffer, '\n' );

 		if ( p ) {
 			off_t offset;

 			offset = lseek ( fd, 0L, SEEK_CUR );               // Get the current file descriptor offset
 			lseek ( fd, offset-n + (p-buffer) + 1, SEEK_SET ); // Set the file descriptor offset to right after the \n

 			p[1] = 0;
 		}
 		return buffer;
 	}

 	else
 		return 0;
 }

 static struct dep_t *build_dep ( void )
 {
 	int fd;
 	struct utsname un;
 	struct dep_t *first = 0;
 	struct dep_t *current = 0;
 	char buffer[256];
 	char *filename = buffer;
 	int continuation_line = 0;

 	if ( uname ( &un ))
 		return 0;

 	// check for buffer overflow in following code
 	if ( bb_strlen ( un.release ) > ( sizeof( buffer ) - 64 )) {
 		return 0;
 	}

 	strcpy ( filename, "/lib/modules/" );
 	strcat ( filename, un.release );
 	strcat ( filename, "/modules.dep" );

 	if (( fd = open ( filename, O_RDONLY )) < 0 ) {

 		/* Ok, that didn't work.  Fall back to looking in /lib/modules */
 		if (( fd = open ( "/lib/modules/modules.dep", O_RDONLY )) < 0 ) {
 			return 0;
 		}
 	}

 	while ( reads ( fd, buffer, sizeof( buffer ))) {
 		int l = bb_strlen ( buffer );
 		char *p = 0;

 		while ( isspace ( buffer [l-1] )) {
 			buffer [l-1] = 0;
 			l--;
 		}

 		if ( l == 0 ) {
 			continuation_line = 0;
 			continue;
 		}

 		if ( !continuation_line ) {
 			char *col = strchr ( buffer, ':' );

 			if ( col ) {
 				char *mods;
 				char *mod;
 				int ext = 0;

 				*col = 0;
 				mods = strrchr ( buffer, '/' );

 				if ( !mods )
 					mods = buffer;
 				else
 					mods++;

 				if (( *(col-2) == '.' ) && ( *(col-1) == 'o' ))
 					ext = 2;

 				mod = bb_xstrndup ( mods, col - mods - ext );

 				if ( !current ) {
 					first = current = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
 				}
 				else {
 					current-> m_next = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
 					current = current-> m_next;
 				}
 				current-> m_module  = mod;
 				current-> m_options = 0;
 				current-> m_isalias = 0;
 				current-> m_depcnt  = 0;
 				current-> m_deparr  = 0;
 				current-> m_next    = 0;

 				//printf ( "%s:\n", mod );

 				p = col + 1;
 			}
 			else
 				p = 0;
 		}
 		else
 			p = buffer;

 		if ( p && *p ) {
 			char *end = &buffer [l-1];
 			char *deps = strrchr ( end, '/' );
 			char *dep;
 			int ext = 0;

 			while ( isblank ( *end ) || ( *end == '\\' ))
 				end--;

 			deps = strrchr ( p, '/' );

 			if ( !deps || ( deps < p )) {
 				deps = p;

 				while ( isblank ( *deps ))
 					deps++;
 			}
 			else
 				deps++;

 			if (( *(end-1) == '.' ) && ( *end == 'o' ))
 				ext = 2;

 			/* Cope with blank lines */
 			if ((end-deps-ext+1) <= 0)
 				continue;

 			dep = bb_xstrndup ( deps, end - deps - ext + 1 );

 			current-> m_depcnt++;
 			current-> m_deparr = (char **) xrealloc ( current-> m_deparr, sizeof ( char *) * current-> m_depcnt );
 			current-> m_deparr [current-> m_depcnt - 1] = dep;

 			//printf ( "    %d) %s\n", current-> m_depcnt, current-> m_deparr [current-> m_depcnt -1] );
 		}

 		if ( buffer [l-1] == '\\' )
 			continuation_line = 1;
 		else
 			continuation_line = 0;
 	}
 	close ( fd );

 	// alias parsing is not 100% correct (no correct handling of continuation lines within an alias) !

 	if (( fd = open ( "/etc/modules.conf", O_RDONLY )) < 0 )
 		if (( fd = open ( "/etc/conf.modules", O_RDONLY )) < 0 )
 			return first;

 	continuation_line = 0;
 	while ( reads ( fd, buffer, sizeof( buffer ))) {
 		int l;
 		char *p;

 		p = strchr ( buffer, '#' );
 		if ( p )
 			*p = 0;

 		l = bb_strlen ( buffer );

 		while ( l && isspace ( buffer [l-1] )) {
 			buffer [l-1] = 0;
 			l--;
 		}

 		if ( l == 0 ) {
 			continuation_line = 0;
 			continue;
 		}

 		if ( !continuation_line ) {
 			if (( strncmp ( buffer, "alias", 5 ) == 0 ) && isspace ( buffer [5] )) {
 				char *alias, *mod;

 				if ( parse_tag_value ( buffer + 6, &alias, &mod )) {
 					// fprintf ( stderr, "ALIAS: '%s' -> '%s'\n", alias, mod );

 					if ( !current ) {
 						first = current = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
 					}
 					else {
 						current-> m_next = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
 						current = current-> m_next;
 					}
 					current-> m_module  = bb_xstrdup ( alias );
 					current-> m_isalias = 1;

 					if (( strcmp ( alias, "off" ) == 0 ) || ( strcmp ( alias, "null" ) == 0 )) {
 						current-> m_depcnt = 0;
 						current-> m_deparr = 0;
 					}
 					else {
 						current-> m_depcnt  = 1;
 						current-> m_deparr  = xmalloc ( 1 * sizeof( char * ));
 						current-> m_deparr[0] = bb_xstrdup ( mod );
 					}
 					current-> m_next    = 0;
 				}
 			}
 			else if (( strncmp ( buffer, "options", 7 ) == 0 ) && isspace ( buffer [7] )) {
 				char *mod, *opt;

 				if ( parse_tag_value ( buffer + 8, &mod, &opt )) {
 					struct dep_t *dt;

 					for ( dt = first; dt; dt = dt-> m_next ) {
 						if ( strcmp ( dt-> m_module, mod ) == 0 )
 							break;
 					}
 					if ( dt ) {
 						dt-> m_options = xrealloc ( dt-> m_options, bb_strlen( opt ) + 1 );
 						strcpy ( dt-> m_options, opt );

 						// fprintf ( stderr, "OPTION: '%s' -> '%s'\n", dt-> m_module, dt-> m_options );
 					}
 				}
 			}
 		}
 	}
 	close ( fd );

 	return first;
 }

 /* return 1 = loaded, 0 = not loaded, -1 = can't tell */
 static int already_loaded (const char *name)
 {
 	int fd;
 	char buffer[256];

 	fd = open ("/proc/modules", O_RDONLY);
 	if (fd < 0)
 		return -1;

 	while ( reads ( fd, buffer, sizeof( buffer ))) {
 		char *p;

 		p = strchr (buffer, ' ');
 		if (p) {
 			*p = 0;
 			if (strcmp (name, buffer) == 0) {
 				close (fd);
 				return 1;
 			}
 		}
 	}

 	close (fd);
 	return 0;
 }

 static int mod_process ( struct mod_list_t *list, int do_insert )
 {
 	char lcmd [256];
 	int rc = 1;

 	while ( list ) {
 		*lcmd = '\0';
 		if ( do_insert ) {
 			if (already_loaded (list->m_module) != 1)
 				snprintf ( lcmd, sizeof( lcmd ) - 1, "insmod %s %s %s %s %s", do_syslog ? "-s" : "", autoclean ? "-k" : "", quiet ? "-q" : "", list-> m_module, list-> m_options ? list-> m_options : "" );
 		} else {
 			if (already_loaded (list->m_module) != 0)
 				snprintf ( lcmd, sizeof( lcmd ) - 1, "rmmod %s %s", do_syslog ? "-s" : "", list-> m_module );
 		}

 		if ( verbose )
 			printf ( "%s\n", lcmd );
 		if ( !show_only && *lcmd) {
 			int rc2 = system ( lcmd );
 			if (do_insert) rc = rc2; /* only last module matters */
 			else if (!rc2) rc = 0; /* success if remove any mod */
 		}

 		list = do_insert ? list-> m_prev : list-> m_next;
 	}
 	return (show_only) ? 0 : rc;
 }

 static void check_dep ( char *mod, struct mod_list_t **head, struct mod_list_t **tail )
 {
 	struct mod_list_t *find;
 	struct dep_t *dt;
 	char *opt = 0;
 	int lm;

 	// remove .o extension
 	lm = bb_strlen ( mod );
 	if (( mod [lm-2] == '.' ) && ( mod [lm-1] == 'o' ))
 		mod [lm-2] = 0;

 	// check dependencies
 	for ( dt = depend; dt; dt = dt-> m_next ) {
 		if ( strcmp ( dt-> m_module, mod ) == 0 ) {
 			opt = dt-> m_options;
 			break;
 		}
 	}

 	// resolve alias names
 	while ( dt && dt-> m_isalias ) {
 		if ( dt-> m_depcnt == 1 ) {
 			struct dep_t *adt;

 			for ( adt = depend; adt; adt = adt-> m_next ) {
 				if ( strcmp ( adt-> m_module, dt-> m_deparr [0] ) == 0 )
 					break;
 			}
 			if ( adt ) {
 				dt = adt;
 				mod = dt-> m_module;
 				if ( !opt )
 					opt = dt-> m_options;
 			}
 			else
 				return;
 		}
 		else
 			return;
 	}

 	// search for duplicates
 	for ( find = *head; find; find = find-> m_next ) {
 		if ( !strcmp ( mod, find-> m_module )) {
 			// found -> dequeue it

 			if ( find-> m_prev )
 				find-> m_prev-> m_next = find-> m_next;
 			else
 				*head = find-> m_next;

 			if ( find-> m_next )
 				find-> m_next-> m_prev = find-> m_prev;
 			else
 				*tail = find-> m_prev;

 			break; // there can be only one duplicate
 		}
 	}

 	if ( !find ) { // did not find a duplicate
 		find = (struct mod_list_t *) xmalloc ( sizeof(struct mod_list_t));
 		find-> m_module = mod;
 		find-> m_options = opt;
 	}

 	// enqueue at tail
 	if ( *tail )
 		(*tail)-> m_next = find;
 	find-> m_prev   = *tail;
 	find-> m_next   = 0;

 	if ( !*head )
 		*head = find;
 	*tail = find;

 	if ( dt ) {
 		int i;

 		for ( i = 0; i < dt-> m_depcnt; i++ )
 			check_dep ( dt-> m_deparr [i], head, tail );
 	}
 }


 static int mod_insert ( char *mod, int argc, char **argv )
 {
 	struct mod_list_t *tail = 0;
 	struct mod_list_t *head = 0;
 	int rc;

 	// get dep list for module mod
 	check_dep ( mod, &head, &tail );

 	if ( head && tail ) {
 		if ( argc ) {
 			int i;
 			int l = 0;

 			// append module args
 			for ( i = 0; i < argc; i++ )
 				l += ( bb_strlen ( argv [i] ) + 1 );

 			head-> m_options = xrealloc ( head-> m_options, l + 1 );
 			head-> m_options [0] = 0;

 			for ( i = 0; i < argc; i++ ) {
 				strcat ( head-> m_options, argv [i] );
 				strcat ( head-> m_options, " " );
 			}
 		}

 		// process tail ---> head
 		rc = mod_process ( tail, 1 );
 	}
 	else
 		rc = 1;

 	return rc;
 }

 static int mod_remove ( char *mod )
 {
 	int rc;
 	static struct mod_list_t rm_a_dummy = { "-a", 0, 0 };

 	struct mod_list_t *head = 0;
 	struct mod_list_t *tail = 0;

 	if ( mod )
 		check_dep ( mod, &head, &tail );
 	else  // autoclean
 		head = tail = &rm_a_dummy;

 	if ( head && tail )
 		rc = mod_process ( head, 0 );  // process head ---> tail
 	else
 		rc = 1;
 	return rc;

 }


 extern int modprobe_main(int argc, char** argv)
 {
 	int	opt;
 	int remove_opt = 0;

 	autoclean = show_only = quiet = do_syslog = verbose = 0;

 	while ((opt = getopt(argc, argv, "acdklnqrst:vVC:")) != -1) {
 		switch(opt) {
 		case 'c': // no config used
 		case 'l': // no pattern matching
 			return EXIT_SUCCESS;
 			break;
 		case 'C': // no config used
 		case 't': // no pattern matching
 			bb_error_msg_and_die("-t and -C not supported");

 		case 'a': // ignore
 		case 'd': // ignore
 			break;
 		case 'k':
 			autoclean++;
 			break;
 		case 'n':
 			show_only++;
 			break;
 		case 'q':
 			quiet++;
 			break;
 		case 'r':
 			remove_opt++;
 			break;
 		case 's':
 			do_syslog++;
 			break;
 		case 'v':
 			verbose++;
 			break;
 		case 'V':
 		default:
 			bb_show_usage();
 			break;
 		}
 	}

 	depend = build_dep ( );

 	if ( !depend )
 		bb_error_msg_and_die ( "could not parse modules.dep\n" );

 	if (remove_opt) {
 		int rc = EXIT_SUCCESS;
 		do {
 			if (mod_remove ( optind < argc ?
 					 bb_xstrdup (argv [optind]) : NULL )) {
 				bb_error_msg ("failed to remove module %s",
 					argv [optind] );
 				rc = EXIT_FAILURE;
 			}
 		} while ( ++optind < argc );

 		return rc;
 	}

 	if (optind >= argc)
 		bb_error_msg_and_die ( "No module or pattern provided\n" );

 	if ( mod_insert ( bb_xstrdup ( argv [optind] ), argc - optind - 1, argv + optind + 1 ))
 		bb_error_msg_and_die ( "failed to load module %s", argv [optind] );

 	return EXIT_SUCCESS;
 }
	/* vi: set sw=4 ts=4: */
	/*
	* Modprobe written from scratch for BusyBox
	*
	* Copyright (c) 2002 by Robert Griebl, griebl@gmx.de
	* Copyright (c) 2003 by Andrew Dennison, andrew.dennison@motec.com.au
	*
	* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*
	*/

	#include <sys/utsname.h>
	#include <getopt.h>
	#include <stdlib.h>
	#include <unistd.h>
	#include <syslog.h>
	#include <string.h>
	#include <ctype.h>
	#include <fcntl.h>
	#include "busybox.h"



	struct dep_t {
	char * m_module;
	char * m_options;

	int m_isalias : 1;
	int m_reserved : 15;

	int m_depcnt : 16;
	char ** m_deparr;

	struct dep_t * m_next;
	};

	struct mod_list_t {
	char * m_module;
	char * m_options;

	struct mod_list_t * m_prev;
	struct mod_list_t * m_next;
	};


	static struct dep_t *depend;
	static int autoclean, show_only, quiet, do_syslog, verbose;

	int parse_tag_value ( char buffer, char ptag, char *pvalue )
	{
	char tag, value;

	while ( isspace ( *buffer ))
	buffer++;
	tag = value = buffer;
	while ( !isspace ( *value ))
	value++;
	*value++ = 0;
	while ( isspace ( *value ))
	value++;

	*ptag = tag;
	*pvalue = value;

	return bb_strlen( tag ) && bb_strlen( value );
	}

	/* Jump through hoops to simulate how fgets() grabs just one line at a
	* time... Don't use any stdio since modprobe gets called from a kernel
	* thread and stdio junk can overflow the limited stack...
	*/
	static char reads ( int fd, char buffer, size_t len )
	{
	int n = read ( fd, buffer, len );

	if ( n > 0 ) {
	char *p;

	buffer [len-1] = 0;
	p = strchr ( buffer, '\n' );

	if ( p ) {
	off_t offset;

	offset = lseek ( fd, 0L, SEEK_CUR ); // Get the current file descriptor offset
	lseek ( fd, offset-n + (p-buffer) + 1, SEEK_SET ); // Set the file descriptor offset to right after the \n

	p[1] = 0;
	}
	return buffer;
	}

	else
	return 0;
	}

	static struct dep_t *build_dep ( void )
	{
	int fd;
	struct utsname un;
	struct dep_t *first = 0;
	struct dep_t *current = 0;
	char buffer[256];
	char *filename = buffer;
	int continuation_line = 0;

	if ( uname ( &un ))
	return 0;

	// check for buffer overflow in following code
	if ( bb_strlen ( un.release ) > ( sizeof( buffer ) - 64 )) {
	return 0;
	}

	strcpy ( filename, "/lib/modules/" );
	strcat ( filename, un.release );
	strcat ( filename, "/modules.dep" );

	if (( fd = open ( filename, O_RDONLY )) < 0 ) {

	/* Ok, that didn't work. Fall back to looking in /lib/modules */
	if (( fd = open ( "/lib/modules/modules.dep", O_RDONLY )) < 0 ) {
	return 0;
	}
	}

	while ( reads ( fd, buffer, sizeof( buffer ))) {
	int l = bb_strlen ( buffer );
	char *p = 0;

	while ( isspace ( buffer [l-1] )) {
	buffer [l-1] = 0;
	l--;
	}

	if ( l == 0 ) {
	continuation_line = 0;
	continue;
	}

	if ( !continuation_line ) {
	char *col = strchr ( buffer, ':' );

	if ( col ) {
	char *mods;
	char *mod;
	int ext = 0;

	*col = 0;
	mods = strrchr ( buffer, '/' );

	if ( !mods )
	mods = buffer;
	else
	mods++;

	if (( (col-2) == '.' ) && ( (col-1) == 'o' ))
	ext = 2;

	mod = bb_xstrndup ( mods, col - mods - ext );

	if ( !current ) {
	first = current = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
	}
	else {
	current-> m_next = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
	current = current-> m_next;
	}
	current-> m_module = mod;
	current-> m_options = 0;
	current-> m_isalias = 0;
	current-> m_depcnt = 0;
	current-> m_deparr = 0;
	current-> m_next = 0;

	//printf ( "%s:\n", mod );

	p = col + 1;
	}
	else
	p = 0;
	}
	else
	p = buffer;

	if ( p && *p ) {
	char *end = &buffer [l-1];
	char *deps = strrchr ( end, '/' );
	char *dep;
	int ext = 0;

	while ( isblank ( end ) \|\| ( end == '\\' ))
	end--;

	deps = strrchr ( p, '/' );

	if ( !deps \|\| ( deps < p )) {
	deps = p;

	while ( isblank ( *deps ))
	deps++;
	}
	else
	deps++;

	if (( (end-1) == '.' ) && ( end == 'o' ))
	ext = 2;

	/* Cope with blank lines */
	if ((end-deps-ext+1) <= 0)
	continue;

	dep = bb_xstrndup ( deps, end - deps - ext + 1 );

	current-> m_depcnt++;
	current-> m_deparr = (char *) xrealloc ( current-> m_deparr, sizeof ( char ) * current-> m_depcnt );
	current-> m_deparr [current-> m_depcnt - 1] = dep;

	//printf ( " %d) %s\n", current-> m_depcnt, current-> m_deparr [current-> m_depcnt -1] );
	}

	if ( buffer [l-1] == '\\' )
	continuation_line = 1;
	else
	continuation_line = 0;
	}
	close ( fd );

	// alias parsing is not 100% correct (no correct handling of continuation lines within an alias) !

	if (( fd = open ( "/etc/modules.conf", O_RDONLY )) < 0 )
	if (( fd = open ( "/etc/conf.modules", O_RDONLY )) < 0 )
	return first;

	continuation_line = 0;
	while ( reads ( fd, buffer, sizeof( buffer ))) {
	int l;
	char *p;

	p = strchr ( buffer, '#' );
	if ( p )
	*p = 0;

	l = bb_strlen ( buffer );

	while ( l && isspace ( buffer [l-1] )) {
	buffer [l-1] = 0;
	l--;
	}

	if ( l == 0 ) {
	continuation_line = 0;
	continue;
	}

	if ( !continuation_line ) {
	if (( strncmp ( buffer, "alias", 5 ) == 0 ) && isspace ( buffer [5] )) {
	char alias, mod;

	if ( parse_tag_value ( buffer + 6, &alias, &mod )) {
	// fprintf ( stderr, "ALIAS: '%s' -> '%s'\n", alias, mod );

	if ( !current ) {
	first = current = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
	}
	else {
	current-> m_next = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
	current = current-> m_next;
	}
	current-> m_module = bb_xstrdup ( alias );
	current-> m_isalias = 1;

	if (( strcmp ( alias, "off" ) == 0 ) \|\| ( strcmp ( alias, "null" ) == 0 )) {
	current-> m_depcnt = 0;
	current-> m_deparr = 0;
	}
	else {
	current-> m_depcnt = 1;
	current-> m_deparr = xmalloc ( 1 * sizeof( char * ));
	current-> m_deparr[0] = bb_xstrdup ( mod );
	}
	current-> m_next = 0;
	}
	}
	else if (( strncmp ( buffer, "options", 7 ) == 0 ) && isspace ( buffer [7] )) {
	char mod, opt;

	if ( parse_tag_value ( buffer + 8, &mod, &opt )) {
	struct dep_t *dt;

	for ( dt = first; dt; dt = dt-> m_next ) {
	if ( strcmp ( dt-> m_module, mod ) == 0 )
	break;
	}
	if ( dt ) {
	dt-> m_options = xrealloc ( dt-> m_options, bb_strlen( opt ) + 1 );
	strcpy ( dt-> m_options, opt );

	// fprintf ( stderr, "OPTION: '%s' -> '%s'\n", dt-> m_module, dt-> m_options );
	}
	}
	}
	}
	}
	close ( fd );

	return first;
	}

	/* return 1 = loaded, 0 = not loaded, -1 = can't tell */
	static int already_loaded (const char *name)
	{
	int fd;
	char buffer[256];

	fd = open ("/proc/modules", O_RDONLY);
	if (fd < 0)
	return -1;

	while ( reads ( fd, buffer, sizeof( buffer ))) {
	char *p;

	p = strchr (buffer, ' ');
	if (p) {
	*p = 0;
	if (strcmp (name, buffer) == 0) {
	close (fd);
	return 1;
	}
	}
	}

	close (fd);
	return 0;
	}

	static int mod_process ( struct mod_list_t *list, int do_insert )
	{
	char lcmd [256];
	int rc = 1;

	while ( list ) {
	*lcmd = '\0';
	if ( do_insert ) {
	if (already_loaded (list->m_module) != 1)
	snprintf ( lcmd, sizeof( lcmd ) - 1, "insmod %s %s %s %s %s", do_syslog ? "-s" : "", autoclean ? "-k" : "", quiet ? "-q" : "", list-> m_module, list-> m_options ? list-> m_options : "" );
	} else {
	if (already_loaded (list->m_module) != 0)
	snprintf ( lcmd, sizeof( lcmd ) - 1, "rmmod %s %s", do_syslog ? "-s" : "", list-> m_module );
	}

	if ( verbose )
	printf ( "%s\n", lcmd );
	if ( !show_only && *lcmd) {
	int rc2 = system ( lcmd );
	if (do_insert) rc = rc2; /* only last module matters */
	else if (!rc2) rc = 0; /* success if remove any mod */
	}

	list = do_insert ? list-> m_prev : list-> m_next;
	}
	return (show_only) ? 0 : rc;
	}

	static void check_dep ( char mod, struct mod_list_t head, struct mod_list_t *tail )
	{
	struct mod_list_t *find;
	struct dep_t *dt;
	char *opt = 0;
	int lm;

	// remove .o extension
	lm = bb_strlen ( mod );
	if (( mod [lm-2] == '.' ) && ( mod [lm-1] == 'o' ))
	mod [lm-2] = 0;

	// check dependencies
	for ( dt = depend; dt; dt = dt-> m_next ) {
	if ( strcmp ( dt-> m_module, mod ) == 0 ) {
	opt = dt-> m_options;
	break;
	}
	}

	// resolve alias names
	while ( dt && dt-> m_isalias ) {
	if ( dt-> m_depcnt == 1 ) {
	struct dep_t *adt;

	for ( adt = depend; adt; adt = adt-> m_next ) {
	if ( strcmp ( adt-> m_module, dt-> m_deparr [0] ) == 0 )
	break;
	}
	if ( adt ) {
	dt = adt;
	mod = dt-> m_module;
	if ( !opt )
	opt = dt-> m_options;
	}
	else
	return;
	}
	else
	return;
	}

	// search for duplicates
	for ( find = *head; find; find = find-> m_next ) {
	if ( !strcmp ( mod, find-> m_module )) {
	// found -> dequeue it

	if ( find-> m_prev )
	find-> m_prev-> m_next = find-> m_next;
	else
	*head = find-> m_next;

	if ( find-> m_next )
	find-> m_next-> m_prev = find-> m_prev;
	else
	*tail = find-> m_prev;

	break; // there can be only one duplicate
	}
	}

	if ( !find ) { // did not find a duplicate
	find = (struct mod_list_t *) xmalloc ( sizeof(struct mod_list_t));
	find-> m_module = mod;
	find-> m_options = opt;
	}

	// enqueue at tail
	if ( *tail )
	(*tail)-> m_next = find;
	find-> m_prev = *tail;
	find-> m_next = 0;

	if ( !*head )
	*head = find;
	*tail = find;

	if ( dt ) {
	int i;

	for ( i = 0; i < dt-> m_depcnt; i++ )
	check_dep ( dt-> m_deparr [i], head, tail );
	}
	}



	static int mod_insert ( char mod, int argc, char *argv )
	{
	struct mod_list_t *tail = 0;
	struct mod_list_t *head = 0;
	int rc;

	// get dep list for module mod
	check_dep ( mod, &head, &tail );

	if ( head && tail ) {
	if ( argc ) {
	int i;
	int l = 0;

	// append module args
	for ( i = 0; i < argc; i++ )
	l += ( bb_strlen ( argv [i] ) + 1 );

	head-> m_options = xrealloc ( head-> m_options, l + 1 );
	head-> m_options [0] = 0;

	for ( i = 0; i < argc; i++ ) {
	strcat ( head-> m_options, argv [i] );
	strcat ( head-> m_options, " " );
	}
	}

	// process tail ---> head
	rc = mod_process ( tail, 1 );
	}
	else
	rc = 1;

	return rc;
	}

	static int mod_remove ( char *mod )
	{
	int rc;
	static struct mod_list_t rm_a_dummy = { "-a", 0, 0 };

	struct mod_list_t *head = 0;
	struct mod_list_t *tail = 0;

	if ( mod )
	check_dep ( mod, &head, &tail );
	else // autoclean
	head = tail = &rm_a_dummy;

	if ( head && tail )
	rc = mod_process ( head, 0 ); // process head ---> tail
	else
	rc = 1;
	return rc;

	}



	extern int modprobe_main(int argc, char** argv)
	{
	int opt;
	int remove_opt = 0;

	autoclean = show_only = quiet = do_syslog = verbose = 0;

	while ((opt = getopt(argc, argv, "acdklnqrst:vVC:")) != -1) {
	switch(opt) {
	case 'c': // no config used
	case 'l': // no pattern matching
	return EXIT_SUCCESS;
	break;
	case 'C': // no config used
	case 't': // no pattern matching
	bb_error_msg_and_die("-t and -C not supported");

	case 'a': // ignore
	case 'd': // ignore
	break;
	case 'k':
	autoclean++;
	break;
	case 'n':
	show_only++;
	break;
	case 'q':
	quiet++;
	break;
	case 'r':
	remove_opt++;
	break;
	case 's':
	do_syslog++;
	break;
	case 'v':
	verbose++;
	break;
	case 'V':
	default:
	bb_show_usage();
	break;
	}
	}

	depend = build_dep ( );

	if ( !depend )
	bb_error_msg_and_die ( "could not parse modules.dep\n" );

	if (remove_opt) {
	int rc = EXIT_SUCCESS;
	do {
	if (mod_remove ( optind < argc ?
	bb_xstrdup (argv [optind]) : NULL )) {
	bb_error_msg ("failed to remove module %s",
	argv [optind] );
	rc = EXIT_FAILURE;
	}
	} while ( ++optind < argc );

	return rc;
	}

	if (optind >= argc)
	bb_error_msg_and_die ( "No module or pattern provided\n" );

	if ( mod_insert ( bb_xstrdup ( argv [optind] ), argc - optind - 1, argv + optind + 1 ))
	bb_error_msg_and_die ( "failed to load module %s", argv [optind] );

	return EXIT_SUCCESS;
	}