hush/modutils/modprobe.c

484 lines
9.7 KiB
C

/* vi: set sw=4 ts=4: */
/*
* really dumb modprobe implementation for busybox
* Copyright (C) 2001 Lineo, davidm@lineo.com
*
* dependency specific stuff completly rewritten and
* copyright (c) 2002 by Robert Griebl, griebl@gmx.de
*
*/
#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;
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;
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;
/* 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 ( xstrlen ( 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 )
return 0;
while ( reads ( fd, buffer, sizeof( buffer ))) {
int l = xstrlen ( 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 = 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_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;
dep = 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 = xstrlen ( 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;
alias = buffer + 6;
while ( isspace ( *alias ))
alias++;
mod = alias;
while ( !isspace ( *mod ))
mod++;
*mod = 0;
mod++;
while ( isspace ( *mod ))
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 = 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] = xstrdup ( mod );
}
current-> m_next = 0;
}
}
}
close ( fd );
return first;
}
static int mod_process ( struct mod_list_t *list, int do_insert )
{
char lcmd [256];
int rc = 0;
if ( !list )
return 1;
while ( list ) {
if ( do_insert )
snprintf ( lcmd, sizeof( lcmd ) - 1, "insmod %s %s %s %s 2>/dev/null", do_syslog ? "-s" : "", autoclean ? "-k" : "", quiet ? "-q" : "", list-> m_module );
else
snprintf ( lcmd, sizeof( lcmd ) - 1, "rmmod %s %s 2>/dev/null", do_syslog ? "-s" : "", list-> m_module );
if ( verbose )
printf ( "%s\n", lcmd );
if ( !show_only )
rc |= system ( lcmd );
list = do_insert ? list-> m_prev : list-> m_next;
}
return 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;
int lm;
// remove .o extension
lm = xstrlen ( 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 )
break;
}
// resolve alias names
if ( dt && dt-> m_isalias ) {
if ( dt-> m_depcnt == 1 )
check_dep ( dt-> m_deparr [0], head, tail );
printf ( "Got alias: %s -> %s\n", mod, dt-> m_deparr [0] );
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;
}
// 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 = 0;
// get dep list for module mod
check_dep ( mod, &head, &tail );
if ( head && tail ) {
int i;
int l = 0;
// append module args
l = xstrlen ( head-> m_module );
for ( i = 0; i < argc; i++ )
l += ( xstrlen ( argv [i] ) + 1 );
head-> m_module = xrealloc ( head-> m_module, l + 1 );
for ( i = 0; i < argc; i++ ) {
strcat ( head-> m_module, " " );
strcat ( head-> m_module, argv [i] );
}
// process tail ---> head
rc |= mod_process ( tail, 1 );
}
else
rc = 1;
return rc;
}
static void mod_remove ( char *mod )
{
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 )
mod_process ( head, 0 ); // process head ---> tail
}
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
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:
show_usage();
break;
}
}
depend = build_dep ( );
if ( !depend )
error_msg_and_die ( "could not parse modules.dep\n" );
if (remove_opt) {
do {
mod_remove ( optind < argc ? xstrdup ( argv [optind] ) : 0 );
} while ( ++optind < argc );
return EXIT_SUCCESS;
}
if (optind >= argc)
error_msg_and_die ( "No module or pattern provided\n" );
return mod_insert ( xstrdup ( argv [optind] ), argc - optind - 1, argv + optind + 1 ) ? \
EXIT_FAILURE : EXIT_SUCCESS;
}