hopefully the last of the annoying signed/unsigned and mixed type errors
[oweals/busybox.git] / modutils / modprobe.c
index f9aa0aa55fc2ce5d6e0b0c37239068c26f79a9f5..844eb99c5ee3d36a95b3939ca9158fa62a2b4697 100644 (file)
 /* vi: set sw=4 ts=4: */
 /*
- * really dumb modprobe implementation for busybox
- * Copyright (C) 2001 Lineo, davidm@lineo.com
+ * Modprobe written from scratch for BusyBox
  *
- * CONFIG_MODPROBE_DEPEND stuff was added and is
- * Copyright (C) 2002 Robert Griebl, griebl@gmx.de
+ * Copyright (c) 2002 by Robert Griebl, griebl@gmx.de
+ * Copyright (c) 2003 by Andrew Dennison, andrew.dennison@motec.com.au
+ * Copyright (c) 2005 by Jim Bauer, jfbauer@nfr.com
  *
- */
+ * Portions Copyright (c) 2005 by Yann E. MORIN, yann.morin.1998@anciens.enib.fr
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+*/
 
-#include <stdio.h>
+#include <sys/utsname.h>
+#include <sys/types.h>
+#include <sys/wait.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"
 
-static char cmd[128];
+struct mod_opt_t {     /* one-way list of options to pass to a module */
+       char *  m_opt_val;
+       struct mod_opt_t * m_next;
+};
 
-#define CONFIG_MODPROBE_DEPEND
+struct dep_t { /* one-way list of dependency rules */
+       /* a dependency rule */
+       char *  m_name;                         /* the module name*/
+       char *  m_path;                         /* the module file path */
+       struct mod_opt_t *  m_options;  /* the module options */
 
-#ifdef CONFIG_MODPROBE_DEPEND
+       int     m_isalias  : 1;                 /* the module is an alias */
+       int     m_reserved : 15;                /* stuffin' */
 
-#include <sys/utsname.h>
+       int     m_depcnt   : 16;                /* the number of dependable module(s) */
+       char ** m_deparr;                       /* the list of dependable module(s) */
+
+       struct dep_t * m_next;                  /* the next dependency rule */
+};
 
-struct dep_t {
-       char *  m_module;
-       int     m_depcnt;
-       char ** m_deparr;
-       
-       struct dep_t * m_next;
+struct mod_list_t {    /* two-way list of modules to process */
+       /* a module description */
+       char *  m_name;
+       char *  m_path;
+       struct mod_opt_t *  m_options;
+
+       struct mod_list_t * m_prev;
+       struct mod_list_t * m_next;
 };
 
 
-static struct dep_t *build_dep ( )
+static struct dep_t *depend;
+static int autoclean, show_only, quiet, do_syslog, verbose;
+
+static int parse_tag_value ( char *buffer, char **ptag, char **pvalue )
+{
+       char *tag, *value;
+
+       while ( isspace ( *buffer ))
+               buffer++;
+       tag = value = buffer;
+       while ( !isspace ( *value ))
+               if (!*value) return 0;
+               else value++;
+       *value++ = 0;
+       while ( isspace ( *value ))
+               value++;
+       if (!*value) return 0;
+
+       *ptag = tag;
+       *pvalue = value;
+
+       return 1;
+}
+
+/* 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;
+}
+
+/*
+ * This function appends an option to a list
+ */
+struct mod_opt_t *append_option( struct mod_opt_t *opt_list, char *opt )
+{
+       struct mod_opt_t *ol = opt_list;
+
+       if( ol ) {
+               while( ol-> m_next ) {
+                       ol = ol-> m_next;
+               }
+               ol-> m_next = xmalloc( sizeof( struct mod_opt_t ) );
+               ol = ol-> m_next;
+       } else {
+               ol = opt_list = xmalloc( sizeof( struct mod_opt_t ) );
+       }
+
+       ol-> m_opt_val = bb_xstrdup( opt );
+       ol-> m_next = NULL;
+
+       return opt_list;
+}
+
+#if ENABLE_FEATURE_MODPROBE_MULTIPLE_OPTIONS
+/* static char* parse_command_string( char* src, char **dst );
+ *   src: pointer to string containing argument
+ *   dst: pointer to where to store the parsed argument
+ *   return value: the pointer to the first char after the parsed argument,
+ *                 NULL if there was no argument parsed (only trailing spaces).
+ *   Note that memory is allocated with bb_xstrdup when a new argument was
+ *   parsed. Don't forget to free it!
+ */
+#define ARG_EMPTY      0x00
+#define ARG_IN_DQUOTES 0x01
+#define ARG_IN_SQUOTES 0x02
+static char *parse_command_string( char *src, char **dst )
+{
+       int opt_status = ARG_EMPTY;
+       char* tmp_str;
+
+       /* Dumb you, I have nothing to do... */
+       if( src == NULL ) return src;
+
+       /* Skip leading spaces */
+       while( *src == ' ' ) {
+               src++;
+       }
+       /* Is the end of string reached? */
+       if( *src == '\0' ) {
+               return NULL;
+       }
+       /* Reached the start of an argument
+        * By the way, we duplicate a little too much
+        * here but what is too much is freed later. */
+       *dst = tmp_str = bb_xstrdup( src );
+       /* Get to the end of that argument */
+       while(    ( *tmp_str != '\0' )
+              && (    ( *tmp_str != ' ' )
+                   || ( opt_status & ( ARG_IN_DQUOTES | ARG_IN_SQUOTES ) ) ) ) {
+               switch( *tmp_str ) {
+                       case '\'':
+                               if( opt_status & ARG_IN_DQUOTES ) {
+                                       /* Already in double quotes, keep current char as is */
+                               } else {
+                                       /* shift left 1 char, until end of string: get rid of the opening/closing quotes */
+                                       memmove( tmp_str, tmp_str + 1, strlen( tmp_str ) );
+                                       /* mark me: we enter or leave single quotes */
+                                       opt_status ^= ARG_IN_SQUOTES;
+                                       /* Back one char, as we need to re-scan the new char there. */
+                                       tmp_str--;
+                               }
+                       break;
+                       case '"':
+                               if( opt_status & ARG_IN_SQUOTES ) {
+                                       /* Already in single quotes, keep current char as is */
+                               } else {
+                                       /* shift left 1 char, until end of string: get rid of the opening/closing quotes */
+                                       memmove( tmp_str, tmp_str + 1, strlen( tmp_str ) );
+                                       /* mark me: we enter or leave double quotes */
+                                       opt_status ^= ARG_IN_DQUOTES;
+                                       /* Back one char, as we need to re-scan the new char there. */
+                                       tmp_str--;
+                               }
+                       break;
+                       case '\\':
+                               if( opt_status & ARG_IN_SQUOTES ) {
+                                       /* Between single quotes: keep as is. */
+                               } else {
+                                       switch( *(tmp_str+1) ) {
+                                               case 'a':
+                                               case 'b':
+                                               case 't':
+                                               case 'n':
+                                               case 'v':
+                                               case 'f':
+                                               case 'r':
+                                               case '0':
+                                                       /* We escaped a special character. For now, keep
+                                                        * both the back-slash and the following char. */
+                                                       tmp_str++; src++;
+                                                       break;
+                                               default:
+                                                       /* We escaped a space or a single or double quote,
+                                                        * or a back-slash, or a non-escapable char. Remove
+                                                        * the '\' and keep the new current char as is. */
+                                                       memmove( tmp_str, tmp_str + 1, strlen( tmp_str ) );
+                                                       break;
+                                       }
+                               }
+                       break;
+                       /* Any other char that is special shall appear here.
+                        * Example: $ starts a variable
+                       case '$':
+                               do_variable_expansion();
+                               break;
+                        * */
+                       default:
+                               /* any other char is kept as is. */
+                               break;
+               }
+               tmp_str++; /* Go to next char */
+               src++; /* Go to next char to find the end of the argument. */
+       }
+       /* End of string, but still no ending quote */
+       if( opt_status & ( ARG_IN_DQUOTES | ARG_IN_SQUOTES ) ) {
+               bb_error_msg_and_die( "unterminated (single or double) quote in options list: %s", src );
+       }
+       *tmp_str = '\0';
+       *dst = xrealloc( *dst, strlen( *dst ) );
+       return src;
+}
+#else
+#define parse_command_string(src, dst) (0)
+#endif /* ENABLE_FEATURE_MODPROBE_MULTIPLE_OPTIONS */
+
+/*
+ * This function builds a list of dependency rules from /lib/modules/`uname -r\modules.dep.
+ * It then fills every modules and aliases with their  default options, found by parsing
+ * modprobe.conf (or modules.conf, or conf.modules).
+ */
+static struct dep_t *build_dep ( void )
 {
+       int fd;
        struct utsname un;
-       FILE *f;
        struct dep_t *first = 0;
        struct dep_t *current = 0;
-       char buffer [4096];
+       char buffer[2048];
        char *filename = buffer;
        int continuation_line = 0;
-       
+       int k_version;
+
+       k_version = 0;
        if ( uname ( &un ))
+               bb_error_msg_and_die("can't determine kernel version");
+
+       // check for buffer overflow in following code
+       if ( bb_strlen ( un.release ) > ( sizeof( buffer ) - 64 )) {
                return 0;
+       }
+       if (un.release[0] == '2') {
+               k_version = un.release[2] - '0';
+       }
+
        strcpy ( filename, "/lib/modules/" );
-       strcat ( filename, un. release );
+       strcat ( filename, un.release );
        strcat ( filename, "/modules.dep" );
 
-       f = fopen ( filename, "r" );
-       if ( !f )
-               return 0;
-       
-       while ( fgets ( buffer, sizeof( buffer), f )) {
-               int l = strlen ( buffer );
+       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;
-               
-               if ( buffer [l-1] == '\n' ) {
+
+               while ( isspace ( buffer [l-1] )) {
                        buffer [l-1] = 0;
                        l--;
                }
-               
+
                if ( l == 0 ) {
                        continuation_line = 0;
                        continue;
                }
-               
-               if ( !continuation_line ) {             
+
+               /* Is this a new module dep description? */
+               if ( !continuation_line ) {
+                       /* find the dep beginning */
                        char *col = strchr ( buffer, ':' );
-               
+                       char *dot = col;
+
                        if ( col ) {
+                               /* This line is a dep description */
                                char *mods;
+                               char *modpath;
                                char *mod;
-                               
+
+                               /* Find the beginning of the module file name */
                                *col = 0;
                                mods = strrchr ( buffer, '/' );
-                               
+
                                if ( !mods )
-                                       mods = buffer;
+                                       mods = buffer; /* no path for this module */
+                               else
+                                       mods++; /* there was a path for this module... */
+
+                               /* find the path of the module */
+                               modpath = strchr ( buffer, '/' ); /* ... and this is the path */
+                               if ( !modpath )
+                                       modpath = buffer; /* module with no path */
+                               /* find the end of the module name in the file name */
+                               if ( ENABLE_FEATURE_2_6_MODULES &&
+                                    (k_version > 4) && ( *(col-3) == '.' ) &&
+                                    ( *(col-2) == 'k' ) && ( *(col-1) == 'o' ) )
+                                       dot = col - 3;
                                else
-                                       mods++;
-                                       
-                               mod = (char *) malloc ( col - mods + 1 );       
-                               strncpy ( mod, mods, col - mods );
-                               mod [col - mods] = 0;
+                                       if (( *(col-2) == '.' ) && ( *(col-1) == 'o' ))
+                                               dot = col - 2;
 
+                               mod = bb_xstrndup ( mods, dot - mods );
+
+                               /* enqueue new module */
                                if ( !current ) {
-                                       first = current = (struct dep_t *) malloc ( sizeof ( struct dep_t ));
+                                       first = current = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
                                }
                                else {
-                                       current-> m_next = (struct dep_t *) malloc ( sizeof ( struct dep_t ));
+                                       current-> m_next = (struct dep_t *) xmalloc ( sizeof ( struct dep_t ));
                                        current = current-> m_next;
                                }
-                               current-> m_module = mod;
-                               current-> m_depcnt = 0;
-                               current-> m_deparr = 0;
-                               current-> m_next = 0;
-                                               
-                               /* printf ( "%s:\n", mod );      */
-                                               
-                               p = col + 1;            
+                               current-> m_name  = mod;
+                               current-> m_path  = bb_xstrdup(modpath);
+                               current-> m_options = NULL;
+                               current-> m_isalias = 0;
+                               current-> m_depcnt  = 0;
+                               current-> m_deparr  = 0;
+                               current-> m_next    = 0;
+
+                               p = col + 1;
                        }
                        else
+                               /* this line is not a dep description */
                                p = 0;
                }
                else
+                       /* It's a dep description continuation */
                        p = buffer;
-                       
+
+               while ( p && *p && isblank(*p))
+                       p++;
+
+               /* p points to the first dependable module; if NULL, no dependable module */
                if ( p && *p ) {
                        char *end = &buffer [l-1];
-                       char *deps = strrchr ( end, '/' );
+                       char *deps;
                        char *dep;
-                       
+                       char *next;
+                       int ext = 0;
+
                        while ( isblank ( *end ) || ( *end == '\\' ))
                                end--;
-                               
-                       deps = strrchr ( p, '/' );
-                       
-                       if ( !deps || ( deps < p )) {
-                               deps = p;
-               
-                               while ( isblank ( *deps ))
+
+                       do
+                       {
+                               /* search the end of the dependency */
+                               next = strchr (p, ' ' );
+                               if (next)
+                               {
+                                       *next = 0;
+                                       next--;
+                               }
+                               else
+                                       next = end;
+
+                               /* find the beginning of the module file name */
+                               deps = strrchr ( p, '/' );
+
+                               if ( !deps || ( deps < p )) {
+                                       deps = p;
+
+                                       while ( isblank ( *deps ))
+                                               deps++;
+                               }
+                               else
                                        deps++;
-                       }
-                       else
-                               deps++;
-                       
-                       dep = (char *) malloc ( end - deps + 2 );
-                       strncpy ( dep, deps, end - deps + 1 );
-                       dep [end - deps + 1] = 0;
-                       
-                       current-> m_depcnt++;
-                       current-> m_deparr = (char **) realloc ( 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] ); */
+
+                               /* find the end of the module name in the file name */
+                               if ( ENABLE_FEATURE_2_6_MODULES &&
+                                    (k_version > 4) && ( *(next-2) == '.' ) &&
+                                    ( *(next-1) == 'k' )  && ( *next == 'o' ) )
+                                       ext = 3;
+                               else
+                                       if (( *(next-1) == '.' ) && ( *next == 'o' ))
+                                               ext = 2;
+
+                               /* Cope with blank lines */
+                               if ((next-deps-ext+1) <= 0)
+                                       continue;
+                               dep = bb_xstrndup ( deps, next - deps - ext + 1 );
+
+                               /* Add the new dependable module name */
+                               current-> m_depcnt++;
+                               current-> m_deparr = (char **) xrealloc ( current-> m_deparr,
+                                               sizeof ( char *) * current-> m_depcnt );
+                               current-> m_deparr [current-> m_depcnt - 1] = dep;
+
+                               p = next + 2;
+                       } while (next < end);
                }
-       
+
+               /* is there other dependable module(s) ? */
                if ( buffer [l-1] == '\\' )
                        continuation_line = 1;
                else
                        continuation_line = 0;
        }
-       fclose ( f );
-       
+       close ( fd );
+
+       // alias parsing is not 100% correct (no correct handling of continuation lines within an alias) !
+
+       if (!ENABLE_FEATURE_2_6_MODULES
+                       || ( fd = open ( "/etc/modprobe.conf", O_RDONLY )) < 0 )
+               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 )) {
+                                       /* handle alias as a module dependent on the aliased module */
+                                       if ( !current ) {
+                                               first = current = (struct dep_t *) xcalloc ( 1, sizeof ( struct dep_t ));
+                                       }
+                                       else {
+                                               current-> m_next = (struct dep_t *) xcalloc ( 1, sizeof ( struct dep_t ));
+                                               current = current-> m_next;
+                                       }
+                                       current-> m_name  = bb_xstrdup ( alias );
+                                       current-> m_isalias = 1;
+
+                                       if (( strcmp ( mod, "off" ) == 0 ) || ( strcmp ( mod, "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;
+
+                               /* split the line in the module/alias name, and options */
+                               if ( parse_tag_value ( buffer + 8, &mod, &opt )) {
+                                       struct dep_t *dt;
+
+                                       /* find the corresponding module */
+                                       for ( dt = first; dt; dt = dt-> m_next ) {
+                                               if ( strcmp ( dt-> m_name, mod ) == 0 )
+                                                       break;
+                                       }
+                                       if ( dt ) {
+                                               if ( ENABLE_FEATURE_MODPROBE_MULTIPLE_OPTIONS ) {
+                                                       char* new_opt = NULL;
+                                                       while( ( opt = parse_command_string( opt, &new_opt ) ) ) {
+                                                               dt-> m_options = append_option( dt-> m_options, new_opt );
+                                                       }
+                                               } else {
+                                                       dt-> m_options = append_option( dt-> m_options, opt );
+                                               }
+                                       }
+                               }
+                       }
+               }
+       }
+       close ( fd );
+
        return first;
 }
 
-
-static struct dep_t *find_dep ( struct dep_t *dt, char *mod )
+/* return 1 = loaded, 0 = not loaded, -1 = can't tell */
+static int already_loaded (const char *name)
 {
-       int lm = strlen ( mod );
-       int hasext = 0;
-       
-       if (( mod [lm-2] == '.' ) && ( mod [lm-1] == 'o' ))
-               hasext = 1;
-       
-       while ( dt ) {
-               if ( hasext && !strcmp ( dt-> m_module, mod ))
-                       break;
-               else if ( !hasext && !strncmp ( dt-> m_module, mod, strlen ( dt-> m_module ) - 2 ))
-                       break;
-                       
-               dt = dt-> m_next;
+       int fd;
+       char buffer[4096];
+
+       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;
+                       for( p = buffer; ENABLE_FEATURE_2_6_MODULES && *p; p++ ) {
+                               *p = ((*p)=='-')?'_':*p;
+                       }
+                       if (strcmp (name, buffer) == 0) {
+                               close (fd);
+                               return 1;
+                       }
+               }
        }
-       return dt;
+
+       close (fd);
+       return 0;
 }
 
+static int mod_process ( struct mod_list_t *list, int do_insert )
+{
+       int rc = 0;
+       char **argv = NULL;
+       struct mod_opt_t *opts;
+       int argc_malloc; /* never used when CONFIG_FEATURE_CLEAN_UP not defined */
+       int argc;
 
-static void check_dep ( char *mod, int do_syslog, 
-               int show_only, int verbose, int recursing )
+       while ( list ) {
+               argc = 0;
+               if( ENABLE_FEATURE_CLEAN_UP )
+                       argc_malloc = 0;
+               /* If CONFIG_FEATURE_CLEAN_UP is not defined, then we leak memory
+                * each time we allocate memory for argv.
+                * But it is (quite) small amounts of memory that leak each
+                * time a module is loaded,  and it is reclaimed when modprobe
+                * exits anyway (even when standalone shell?).
+                * This could become a problem when loading a module with LOTS of
+                * dependencies, with LOTS of options for each dependencies, with
+                * very little memory on the target... But in that case, the module
+                * would not load because there is no more memory, so there's no
+                * problem. */
+               /* enough for minimal insmod (5 args + NULL) or rmmod (3 args + NULL) */
+               argv = (char**) malloc( 6 * sizeof( char* ) );
+               if ( do_insert ) {
+                       if (already_loaded (list->m_name) != 1) {
+                               argv[argc++] = "insmod";
+                               if (do_syslog)
+                                       argv[argc++] = "-s";
+                               if (autoclean)
+                                       argv[argc++] = "-k";
+                               if (quiet)
+                                       argv[argc++] = "-q";
+                               else if(verbose) /* verbose and quiet are mutually exclusive */
+                                       argv[argc++] = "-v";
+                               argv[argc++] = list-> m_path;
+                               if( ENABLE_FEATURE_CLEAN_UP )
+                                       argc_malloc = argc;
+                               opts = list-> m_options;
+                               while( opts ) {
+                                       /* Add one more option */
+                                       argc++;
+                                       argv = (char**) xrealloc( argv, ( argc + 1 ) * sizeof( char* ) );
+                                       argv[argc-1] = opts-> m_opt_val;
+                                       opts = opts-> m_next;
+                               }
+                       }
+               } else {
+                       /* modutils uses short name for removal */
+                       if (already_loaded (list->m_name) != 0) {
+                               argv[argc++] = "rmmod";
+                               if (do_syslog)
+                                       argv[argc++] = "-s";
+                               argv[argc++] = list->m_name;
+                               if( ENABLE_FEATURE_CLEAN_UP )
+                                       argc_malloc = argc;
+                       }
+               }
+               argv[argc] = NULL;
+
+               if (argc) {
+                       if (verbose) {
+                               printf("%s module %s\n", do_insert?"Loading":"Unloading", list-> m_name );
+                       }
+                       if (!show_only) {
+                               int rc2 = 0;
+                               int status;
+                               switch (fork()) {
+                               case -1:
+                                       rc2 = 1;
+                                       break;
+                               case 0: //child
+                                       execvp(argv[0], argv);
+                                       bb_perror_msg_and_die("exec of %s", argv[0]);
+                                       /* NOTREACHED */
+                               default:
+                                       if (wait(&status) == -1) {
+                                               rc2 = 1;
+                                               break;
+                                       }
+                                       if (WIFEXITED(status))
+                                               rc2 = WEXITSTATUS(status);
+                                       if (WIFSIGNALED(status))
+                                               rc2 = WTERMSIG(status);
+                                       break;
+                               }
+                               if (do_insert) {
+                                       rc = rc2; /* only last module matters */
+                               }
+                               else if (!rc2) {
+                                       rc = 0; /* success if remove any mod */
+                               }
+                       }
+                       if( ENABLE_FEATURE_CLEAN_UP )
+                               /* the last value in the array has index == argc, but
+                                * it is the terminating NULL, so we must not free it. */
+                               while( argc_malloc < argc ) {
+                                       free( argv[argc_malloc++] );
+                       }
+               }
+               if( ENABLE_FEATURE_CLEAN_UP ) {
+                       free( argv );
+                       argv = NULL;
+               }
+               list = do_insert ? list-> m_prev : list-> m_next;
+       }
+       return (show_only) ? 0 : rc;
+}
+
+/*
+ * Builds the dependency list (aka stack) of a module.
+ * head: the highest module in the stack (last to insmod, first to rmmod)
+ * tail: the lowest module in the stack (first to insmod, last to rmmod)
+ */
+static void check_dep ( char *mod, struct mod_list_t **head, struct mod_list_t **tail )
 {
-       static struct dep_t *depend = (struct dep_t *) -1;      
+       struct mod_list_t *find;
        struct dep_t *dt;
-       
-       if ( depend == (struct dep_t *) -1 )
-               depend = build_dep ( );
-       
-       /* printf ( "CHECK: %s (%p)\n", mod, depend ); */
-       
-       if (( dt = find_dep ( depend, mod ))) {
-               int i;
-                       
-               for ( i = 0; i < dt-> m_depcnt; i++ ) 
-                       check_dep ( dt-> m_deparr [i], do_syslog, 
-                                       show_only, verbose, 1);
+       struct mod_opt_t *opt = 0;
+       char *path = 0;
+
+       // check dependencies
+       for ( dt = depend; dt; dt = dt-> m_next ) {
+               if ( strcmp ( dt-> m_name, mod ) == 0) {
+                       break;
+               }
        }
-       if ( recursing  ) {
-               char lcmd [256];
-               
-               snprintf(lcmd, sizeof(lcmd)-1, "insmod %s -q -k %s 2>/dev/null", 
-                               do_syslog ? "-s" : "", mod );
-               if (show_only || verbose)
-                       printf("%s\n", lcmd);
-               if (!show_only)
-                       system ( lcmd );        
+
+       if( !dt ) {
+               bb_error_msg ("module %s not found.", mod);
+               return;
        }
-}      
 
-#endif
-               
+       // resolve alias names
+       while ( dt-> m_isalias ) {
+               if ( dt-> m_depcnt == 1 ) {
+                       struct dep_t *adt;
 
-extern int modprobe_main(int argc, char** argv)
-{
-       int     ch, rc = 0;
-       int     loadall = 0, showconfig = 0, debug = 0, autoclean = 0, list = 0;
-       int     show_only = 0, quiet = 0, remove_opt = 0, do_syslog = 0, verbose = 0;
-       char    *load_type = NULL, *config = NULL;
-
-       while ((ch = getopt(argc, argv, "acdklnqrst:vVC:")) != -1)
-               switch(ch) {
-               case 'a':
-                       loadall++;
-                       break;
-               case 'c':
-                       showconfig++;
-                       break;
-               case 'd':
-                       debug++;
-                       break;
-               case 'k':
-                       autoclean++;
-                       break;
-               case 'l':
-                       list++;
-                       break;
-               case 'n':
-                       show_only++;
-                       break;
-               case 'q':
-                       quiet++;
-                       break;
-               case 'r':
-                       remove_opt++;
-                       break;
-               case 's':
-                       do_syslog++;
-                       break;
-               case 't':
-                       load_type = optarg;
-                       break;
-               case 'v':
-                       verbose++;
-                       break;
-               case 'C':
-                       config = optarg;
-                       break;
-               case 'V':
-               default:
-                       show_usage();
-                       break;
+                       for ( adt = depend; adt; adt = adt-> m_next ) {
+                               if ( strcmp ( adt-> m_name, dt-> m_deparr [0] ) == 0 )
+                                       break;
+                       }
+                       if ( adt ) {
+                               /* This is the module we are aliased to */
+                               struct mod_opt_t *opts = dt-> m_options;
+                               /* Option of the alias are appended to the options of the module */
+                               while( opts ) {
+                                       adt-> m_options = append_option( adt-> m_options, opts-> m_opt_val );
+                                       opts = opts-> m_next;
+                               }
+                               dt = adt;
+                       }
+                       else {
+                               bb_error_msg ("module %s not found.", mod);
+                               return;
+                       }
                }
+               else {
+                       bb_error_msg ("Bad alias %s", dt-> m_name);
+                       return;
+               }
+       }
+
+       mod = dt-> m_name;
+       path = dt-> m_path;
+       opt = dt-> m_options;
 
-       if (load_type || config) {
-               fprintf(stderr, "-t and -C not supported\n");
-               exit(EXIT_FAILURE);
+       // search for duplicates
+       for ( find = *head; find; find = find-> m_next ) {
+               if ( !strcmp ( mod, find-> m_name )) {
+                       // 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 (showconfig)
-               exit(EXIT_SUCCESS);
-       
-       if (list)
-               exit(EXIT_SUCCESS);
-       
-       if (remove_opt) {
-               do {
-                       sprintf(cmd, "rmmod %s %s %s",
-                                       optind >= argc ? "-a" : "",
-                                       do_syslog ? "-s" : "",
-                                       optind < argc ? argv[optind] : "");
-                       if (do_syslog)
-                               syslog(LOG_INFO, "%s", cmd);
-                       if (show_only || verbose)
-                               printf("%s\n", cmd);
-                       if (!show_only)
-                               rc = system(cmd);
-               } while (++optind < argc);
-               exit(EXIT_SUCCESS);
+       if ( !find ) { // did not find a duplicate
+               find = (struct mod_list_t *) xmalloc ( sizeof(struct mod_list_t));
+               find-> m_name = mod;
+               find-> m_path = path;
+               find-> m_options = opt;
        }
 
-       if (optind >= argc) {
-               fprintf(stderr, "No module or pattern provided\n");
-               exit(EXIT_FAILURE);
+       // 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;
+
+               /* Add all dependable module for that new module */
+               for ( i = 0; i < dt-> m_depcnt; i++ )
+                       check_dep ( dt-> m_deparr [i], head, tail );
        }
+}
 
-       sprintf(cmd, "insmod %s %s %s",
-                       do_syslog ? "-s" : "",
-                       quiet ? "-q" : "",
-                       autoclean ? "-k" : "");
+static int mod_insert ( char *mod, int argc, char **argv )
+{
+       struct mod_list_t *tail = 0;
+       struct mod_list_t *head = 0;
+       int rc;
 
-#ifdef CONFIG_MODPROBE_DEPEND
-       check_dep ( argv [optind], do_syslog, show_only, verbose, 0);
-#endif
+       // get dep list for module mod
+       check_dep ( mod, &head, &tail );
 
-       while (optind < argc) {
-               strcat(cmd, " ");
-               strcat(cmd, argv[optind]);
-               optind++;
+       if ( head && tail ) {
+               if( argc ) {
+                       int i;
+                       // append module args
+                       for ( i = 0; i < argc; i++ )
+                               head->m_options = append_option( head->m_options, argv[i] );
+               }
+
+               // process tail ---> head
+               rc = mod_process ( tail, 1 );
        }
-       if (do_syslog)
-               syslog(LOG_INFO, "%s", cmd);
-       if (show_only || verbose)
-               printf("%s\n", cmd);
-       if (!show_only)
-               rc = system(cmd);
        else
-               rc = 0;
+               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;
 
-       exit(rc ? EXIT_FAILURE : EXIT_SUCCESS);
 }
 
+extern int modprobe_main(int argc, char** argv)
+{
+       int     opt;
+       int rc = EXIT_SUCCESS;
+       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++; verbose=0;
+                               break;
+                       case 'r':
+                               remove_opt++;
+                               break;
+                       case 's':
+                               do_syslog++;
+                               break;
+                       case 'v':
+                               verbose++; quiet=0;
+                               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) {
+               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 );
+       } else {
+               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] );
+       }
+
+       /* Here would be a good place to free up memory allocated during the dependencies build. */
+
+       return rc;
+}