"formated" -> "formatted" throughout the code base.
[oweals/busybox.git] / applets / applets.c
index 9dcfe6b85119d1afb8fa27fe8ee1392ed0a05bba..bd8cfec5da2356ace2e14c4b57be656cb9f47dc7 100644 (file)
  * isn't something I'm going to worry about...  If you wrote something
  * here, please feel free to acknowledge your work.
  *
- * 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
- *
- * Based in part on code from sash, Copyright (c) 1999 by David I. Bell 
+ * Based in part on code from sash, Copyright (c) 1999 by David I. Bell
  * Permission has been granted to redistribute this code under the GPL.
  *
+ * Licensed under GPLv2 or later, see file License in this tarball for details.
  */
 
+#include "busybox.h"
 #include <unistd.h>
-#include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
-#include "busybox.h"
+#include <assert.h>
+
+#if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
+static const char usage_messages[] =
+#define MAKE_USAGE
+#include "usage.h"
+#include "applets.h"
+;
+#undef MAKE_USAGE
+#else
+#define usage_messages 0
+#endif /* ENABLE_SHOW_USAGE */
 
 #undef APPLET
 #undef APPLET_NOUSAGE
 #undef PROTOTYPES
 #include "applets.h"
 
-struct BB_applet *applet_using;
+static struct BB_applet *applet_using;
 
 /* The -1 arises because of the {0,NULL,0,-1} entry above. */
 const size_t NUM_APPLETS = (sizeof (applets) / sizeof (struct BB_applet) - 1);
 
 
-#ifdef CONFIG_FEATURE_SUID
-
-static void check_suid ( struct BB_applet *app );
-
 #ifdef CONFIG_FEATURE_SUID_CONFIG
 
-#include <sys/stat.h>
 #include <ctype.h>
-#include "pwd.h"
-#include "grp.h"
-
-static int parse_config_file ( void );
-
-static int config_ok;
+#include "pwd_.h"
+#include "grp_.h"
 
 #define CONFIG_FILE "/etc/busybox.conf"
 
-// applets [] is const, so we have to define this "override" structure
-struct BB_suid_config {
-       struct BB_applet *m_applet;
-
-       uid_t  m_uid;
-       gid_t  m_gid;
-       mode_t m_mode;
-       
-       struct BB_suid_config *m_next;
-};
+/* applets [] is const, so we have to define this "override" structure */
+static struct BB_suid_config
+{
+  struct BB_applet *m_applet;
 
-static struct BB_suid_config *suid_config;
+  uid_t m_uid;
+  gid_t m_gid;
+  mode_t m_mode;
 
-#endif // CONFIG_FEATURE_SUID_CONFIG
+  struct BB_suid_config *m_next;
+} *suid_config;
 
-#endif // CONFIG_FEATURE_SUID
+static int suid_cfg_readable;
 
+/* check if u is member of group g */
+static int ingroup (uid_t u, gid_t g)
+{
+  struct group *grp = getgrgid (g);
 
+  if (grp) {
+       char **mem;
 
-extern void show_usage(void)
-{
-       const char *format_string;
-       const char *usage_string = usage_messages;
-       int i;
+       for (mem = grp->gr_mem; *mem; mem++) {
+         struct passwd *pwd = getpwnam (*mem);
 
-       for (i = applet_using - applets; i > 0; ) {
-               if (!*usage_string++) {
-                       --i;
-               }
+         if (pwd && (pwd->pw_uid == u))
+               return 1;
        }
-       format_string = "%s\n\nUsage: %s %s\n\n";
-       if(*usage_string == 0)
-               format_string = "%s\n\nNo help available.\n\n";
-       fprintf(stderr, format_string,
-                       full_version, applet_using->name, usage_string);
-       exit(EXIT_FAILURE);
+  }
+  return 0;
 }
 
-static int applet_name_compare(const void *x, const void *y)
+/* This should probably be a libbb routine.  In that case,
+ * I'd probably rename it to something like bb_trimmed_slice.
+ */
+static char *get_trimmed_slice(char *s, char *e)
 {
-       const char *name = x;
-       const struct BB_applet *applet = y;
+       /* First, consider the value at e to be nul and back up until we
+        * reach a non-space char.  Set the char after that (possibly at
+        * the original e) to nul. */
+       while (e-- > s) {
+               if (!isspace(*e)) {
+                       break;
+               }
+       }
+       e[1] = 0;
 
-       return strcmp(name, applet->name);
+       /* Next, advance past all leading space and return a ptr to the
+        * first non-space char; possibly the terminating nul. */
+       return skip_whitespace(s);
 }
 
-extern const size_t NUM_APPLETS;
 
-struct BB_applet *find_applet_by_name(const char *name)
-{
-       return bsearch(name, applets, NUM_APPLETS, sizeof(struct BB_applet),
-                       applet_name_compare);
-}
+#define parse_error(x)  { err=x; goto pe_label; }
 
-void run_applet_by_name(const char *name, int argc, char **argv)
+/* Don't depend on the tools to combine strings. */
+static const char config_file[] = CONFIG_FILE;
+
+/* There are 4 chars + 1 nul for each of user/group/other. */
+static const char mode_chars[] = "Ssx-\0Ssx-\0Ttx-";
+
+/* We don't supply a value for the nul, so an index adjustment is
+ * necessary below.  Also, we use unsigned short here to save some
+ * space even though these are really mode_t values. */
+static const unsigned short mode_mask[] = {
+       /*  SST         sst                 xxx   --- */
+       S_ISUID,    S_ISUID|S_IXUSR,    S_IXUSR,    0,  /* user */
+       S_ISGID,    S_ISGID|S_IXGRP,    S_IXGRP,    0,  /* group */
+       0,          S_IXOTH,            S_IXOTH,    0   /* other */
+};
+
+static void parse_config_file(void)
 {
-       static int recurse_level = 0;
-       extern int been_there_done_that; /* From busybox.c */
+       struct BB_suid_config *sct_head;
+       struct BB_suid_config *sct;
+       struct BB_applet *applet;
+       FILE *f;
+       char *err;
+       char *s;
+       char *e;
+       int i, lc, section;
+       char buffer[256];
+       struct stat st;
 
-#ifdef CONFIG_FEATURE_SUID_CONFIG
-       if ( recurse_level == 0 )
-               config_ok = parse_config_file ( );
-#endif
+       assert(!suid_config);           /* Should be set to NULL by bss init. */
 
-       recurse_level++;
-       /* Do a binary search to find the applet entry given the name. */
-       if ((applet_using = find_applet_by_name(name)) != NULL) {
-               applet_name = applet_using->name;
-               if (argv[1] && strcmp(argv[1], "--help") == 0) {
-                       if (strcmp(applet_using->name, "busybox")==0) {
-                               if(argv[2])
-                                 applet_using = find_applet_by_name(argv[2]);
-                                else
-                                 applet_using = NULL;
+       if ((stat(config_file, &st) != 0)                       /* No config file? */
+               || !S_ISREG(st.st_mode)                                 /* Not a regular file? */
+               || (st.st_uid != 0)                                             /* Not owned by root? */
+               || (st.st_mode & (S_IWGRP | S_IWOTH))   /* Writable by non-root? */
+               || !(f = fopen(config_file, "r"))               /* Can not open? */
+               ) {
+               return;
+       }
+
+       suid_cfg_readable = 1;
+       sct_head = NULL;
+       section = lc = 0;
+
+       do {
+               s = buffer;
+
+               if (!fgets(s, sizeof(buffer), f)) { /* Are we done? */
+                       if (ferror(f)) {   /* Make sure it wasn't a read error. */
+                               parse_error("reading");
                        }
-                       if(applet_using)
-                               show_usage();
-                       been_there_done_that=1;
-                       busybox_main(0, NULL);
+                       fclose(f);
+                       suid_config = sct_head; /* Success, so set the pointer. */
+                       return;
                }
-#ifdef CONFIG_FEATURE_SUID
-               check_suid ( applet_using );
-#endif
-                       
-               exit((*(applet_using->main)) (argc, argv));
-       }
-       /* Just in case they have renamed busybox - Check argv[1] */
-       if (recurse_level == 1) {
-               run_applet_by_name("busybox", argc, argv);
-       }
-       recurse_level--;
-}
 
+               lc++;                                   /* Got a (partial) line. */
+
+               /* If a line is too long for our buffer, we consider it an error.
+                * The following test does mistreat one corner case though.
+                * If the final line of the file does not end with a newline and
+                * yet exactly fills the buffer, it will be treated as too long
+                * even though there isn't really a problem.  But it isn't really
+                * worth adding code to deal with such an unlikely situation, and
+                * we do err on the side of caution.  Besides, the line would be
+                * too long if it did end with a newline. */
+               if (!strchr(s, '\n') && !feof(f)) {
+                       parse_error("line too long");
+               }
 
-#ifdef CONFIG_FEATURE_SUID
+               /* Trim leading and trailing whitespace, ignoring comments, and
+                * check if the resulting string is empty. */
+               if (!*(s = get_trimmed_slice(s, strchrnul(s, '#')))) {
+                       continue;
+               }
 
-#ifdef CONFIG_FEATURE_SUID_CONFIG
+               /* Check for a section header. */
+
+               if (*s == '[') {
+                       /* Unlike the old code, we ignore leading and trailing
+                        * whitespace for the section name.  We also require that
+                        * there are no stray characters after the closing bracket. */
+                       if (!(e = strchr(s, ']'))       /* Missing right bracket? */
+                               || e[1]                                 /* Trailing characters? */
+                               || !*(s = get_trimmed_slice(s+1, e)) /* Missing name? */
+                               ) {
+                               parse_error("section header");
+                       }
+                       /* Right now we only have one section so just check it.
+                        * If more sections are added in the future, please don't
+                        * resort to cascading ifs with multiple strcasecmp calls.
+                        * That kind of bloated code is all too common.  A loop
+                        * and a string table would be a better choice unless the
+                        * number of sections is very small. */
+                       if (strcasecmp(s, "SUID") == 0) {
+                               section = 1;
+                               continue;
+                       }
+                       section = -1;   /* Unknown section so set to skip. */
+                       continue;
+               }
 
-// check if u is member of group g
-static int ingroup ( uid_t u, gid_t g )
-{
-       struct group *grp = getgrgid ( g );
-       
-       if ( grp ) {
-               char **mem;
-               
-               for ( mem = grp-> gr_mem; *mem; mem++ ) {
-                       struct passwd *pwd = getpwnam ( *mem );
-               
-                       if ( pwd && ( pwd-> pw_uid == u ))
-                               return 1;
+               /* Process sections. */
+
+               if (section == 1) {             /* SUID */
+                       /* Since we trimmed leading and trailing space above, we're
+                        * now looking for strings of the form
+                        *    <key>[::space::]*=[::space::]*<value>
+                        * where both key and value could contain inner whitespace. */
+
+                       /* First get the key (an applet name in our case). */
+                       if (!!(e = strchr(s, '='))) {
+                               s = get_trimmed_slice(s, e);
+                       }
+                       if (!e || !*s) {        /* Missing '=' or empty key. */
+                               parse_error("keyword");
+                       }
+
+                       /* Ok, we have an applet name.  Process the rhs if this
+                        * applet is currently built in and ignore it otherwise.
+                        * Note: This can hide config file bugs which only pop
+                        * up when the busybox configuration is changed. */
+                       if ((applet = find_applet_by_name(s))) {
+                               /* Note: We currently don't check for duplicates!
+                                * The last config line for each applet will be the
+                                * one used since we insert at the head of the list.
+                                * I suppose this could be considered a feature. */
+                               sct = xmalloc(sizeof(struct BB_suid_config));
+                               sct->m_applet = applet;
+                               sct->m_mode = 0;
+                               sct->m_next = sct_head;
+                               sct_head = sct;
+
+                               /* Get the specified mode. */
+
+                               e = skip_whitespace(e+1);
+
+                               for (i=0 ; i < 3 ; i++) {
+                                       const char *q;
+                                       if (!*(q = strchrnul(mode_chars + 5*i, *e++))) {
+                                               parse_error("mode");
+                                       }
+                                       /* Adjust by -i to account for nul. */
+                                       sct->m_mode |= mode_mask[(q - mode_chars) - i];
+                               }
+
+                               /* Now get the the user/group info. */
+
+                               s = skip_whitespace(e);
+
+                               /* Note: We require whitespace between the mode and the
+                                * user/group info. */
+                               if ((s == e) || !(e = strchr(s, '.'))) {
+                                       parse_error("<uid>.<gid>");
+                               }
+                               *e++ = 0;
+
+                               /* We can't use get_ug_id here since it would exit()
+                                * if a uid or gid was not found.  Oh well... */
+                               {
+                                       char *e2;
+
+                                       sct->m_uid = strtoul(s, &e2, 10);
+                                       if (*e2 || (s == e2)) {
+                                               struct passwd *pwd;
+                                               if (!(pwd = getpwnam(s))) {
+                                                       parse_error("user");
+                                               }
+                                               sct->m_uid = pwd->pw_uid;
+                                       }
+
+                                       sct->m_gid = strtoul(e, &e2, 10);
+                                       if (*e2 || (e == e2)) {
+                                               struct group *grp;
+                                               if (!(grp = getgrnam(e))) {
+                                                       parse_error("group");
+                                               }
+                                               sct->m_gid = grp->gr_gid;
+                                       }
+                               }
+                       }
+                       continue;
+               }
+
+               /* Unknown sections are ignored. */
+
+               /* Encountering configuration lines prior to seeing a
+                * section header is treated as an error.  This is how
+                * the old code worked, but it may not be desirable.
+                * We may want to simply ignore such lines in case they
+                * are used in some future version of busybox. */
+               if (!section) {
+                       parse_error("keyword outside section");
                }
+
+       } while (1);
+
+ pe_label:
+       fprintf(stderr, "Parse error in %s, line %d: %s\n",
+                       config_file, lc, err);
+
+       fclose(f);
+       /* Release any allocated memory before returning. */
+       while (sct_head) {
+               sct = sct_head->m_next;
+               free(sct_head);
+               sct_head = sct;
        }
-       return 0;
+       return;
 }
 
-#endif
-
+#else
+#define parse_config_file()
+#endif /* CONFIG_FEATURE_SUID_CONFIG */
 
-void check_suid ( struct BB_applet *applet )
+#ifdef CONFIG_FEATURE_SUID
+static void check_suid (struct BB_applet *applet)
 {
-       uid_t ruid = getuid ( ); // real [ug]id
-       uid_t rgid = getgid ( );
-                       
+  uid_t ruid = getuid ();               /* real [ug]id */
+  uid_t rgid = getgid ();
+
 #ifdef CONFIG_FEATURE_SUID_CONFIG
-       if ( config_ok ) {
-               struct BB_suid_config *sct;
-               
-               for ( sct = suid_config; sct; sct = sct-> m_next ) {
-                       if ( sct-> m_applet == applet )
-                               break;
-               }               
-               if ( sct ) {
-                       mode_t m = sct-> m_mode;
-                       
-                       if ( sct-> m_uid == ruid ) // same uid
-                               m >>= 6;
-                       else if (( sct-> m_gid == rgid ) || ingroup ( ruid, sct-> m_gid )) // same group / in group
-                               m >>= 3;
-
-                       if (!( m & S_IXOTH ))   // is x bit not set ?
-                               error_msg_and_die ( "You have no permission to run this applet!" );
-               
-                       if (( sct-> m_mode & ( S_ISGID | S_IXGRP )) == ( S_ISGID | S_IXGRP )) { // *both* have to be set for sgid
-                               if ( setegid ( sct-> m_gid ))
-                                       error_msg_and_die ( "BusyBox binary has insufficient rights to set proper GID for applet!" );
-                       }
-                       else
-                               setgid ( rgid ); // no sgid -> drop
-                               
-                       if ( sct-> m_mode & S_ISUID ) {
-                               if ( seteuid ( sct-> m_uid ))
-                                       error_msg_and_die ( "BusyBox binary has insufficient rights to set proper UID for applet!" );
-                       }       
-                       else
-                               setuid ( ruid ); // no suid -> drop
-               }
-               else { // default: drop all priviledges
-                       setgid ( rgid );
-                       setuid ( ruid );
-               }
-               return;
+  if (suid_cfg_readable) {
+       struct BB_suid_config *sct;
+
+       for (sct = suid_config; sct; sct = sct->m_next) {
+         if (sct->m_applet == applet)
+               break;
        }
-       else {
-               static int onetime = 0;
-               
-               if ( !onetime ) {
-                       onetime = 1;
-                       fprintf ( stderr, "Using fallback suid method\n" );
-               }
+       if (sct) {
+         mode_t m = sct->m_mode;
+
+         if (sct->m_uid == ruid)       /* same uid */
+               m >>= 6;
+         else if ((sct->m_gid == rgid) || ingroup (ruid, sct->m_gid))  /* same group / in group */
+               m >>= 3;
+
+         if (!(m & S_IXOTH))           /* is x bit not set ? */
+               bb_error_msg_and_die ("You have no permission to run this applet!");
+
+         if ((sct->m_mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {     /* *both* have to be set for sgid */
+               xsetgid(sct->m_gid);
+         } else xsetgid(rgid);                /* no sgid -> drop */
+
+         if (sct->m_mode & S_ISUID) xsetuid(sct->m_uid);
+         else xsetuid(ruid);                  /* no suid -> drop */
+       } else {
+               /* default: drop all privileges */
+         xsetgid(rgid);
+         xsetuid(ruid);
+       }
+       return;
+  } else {
+#ifndef CONFIG_FEATURE_SUID_CONFIG_QUIET
+       static int onetime = 0;
+
+       if (!onetime) {
+         onetime = 1;
+         fprintf (stderr, "Using fallback suid method\n");
        }
 #endif
+  }
+#endif
 
-       if ( applet-> need_suid == _BB_SUID_ALWAYS ) {
-               if ( geteuid ( ) != 0 ) 
-                       error_msg_and_die ( "This applet requires root priviledges!" );
-       } 
-       else if ( applet-> need_suid == _BB_SUID_NEVER ) {
-               setgid ( rgid ); // drop all priviledges
-               setuid ( ruid );
-       }       
+  if (applet->need_suid == _BB_SUID_ALWAYS) {
+       if (geteuid()) bb_error_msg_and_die("Applet requires root privileges!");
+  } else if (applet->need_suid == _BB_SUID_NEVER) {
+       xsetgid(rgid);                          /* drop all privileges */
+       xsetuid(ruid);
+  }
 }
+#else
+#define check_suid(x)
+#endif /* CONFIG_FEATURE_SUID */
 
-#ifdef CONFIG_FEATURE_SUID_CONFIG
 
 
-#define parse_error(x) { err=x; goto pe_label; }
+#if ENABLE_FEATURE_COMPRESS_USAGE
 
+#include "usage_compressed.h"
+#include "unarchive.h"
 
-int parse_config_file ( void )
+static const char *unpack_usage_messages(void)
 {
-       struct stat st;
-       char *err = 0;
-       FILE *f = 0;
-       int lc = 0;
-
-       suid_config = 0;
-       
-       // is there a config file ?
-       if ( stat ( CONFIG_FILE, &st ) == 0 ) {
-               // is it owned by root with no write perm. for group and others ?
-               if ( S_ISREG( st. st_mode ) && ( st. st_uid == 0 )      && (!( st. st_mode & ( S_IWGRP | S_IWOTH )))) {
-                       // that's ok .. then try to open it
-                       f = fopen ( CONFIG_FILE, "r" );
-
-                       if ( f ) {
-                               char buffer [256];
-                               int section = 0;
-                               
-                               while ( fgets ( buffer, sizeof( buffer ) - 1, f )) {
-                                       char c = buffer [0];
-                                       char *p;
-                               
-                                       lc++;
-                                       
-                                       p = strchr ( buffer, '#' );
-                                       if ( p )
-                                               *p = 0;
-                                       p = buffer + xstrlen ( buffer );
-                                       while (( p > buffer ) && isspace ( *--p ))
-                                               *p = 0;         
-                                               
-                                       if ( p == buffer )
-                                               continue;                                       
-                               
-                                       if ( c == '[' ) {
-                                               p = strchr ( buffer, ']' );
-                                               
-                                               if ( !p || ( p == ( buffer + 1 )))  // no matching ] or empty []
-                                                       parse_error ( "malformed section header" );
-
-                                               *p = 0;
-                                               
-                                               if ( strcasecmp ( buffer + 1, "SUID" ) == 0 )
-                                                       section = 1;
-                                               else
-                                                       section = -1; // unknown section - just skip
-                                       }
-                                       else if ( section ) {
-                                               switch ( section ) {
-                                                       case 1: { // SUID
-                                                               int l;
-                                                               struct BB_applet *applet;
-
-                                                               p = strchr ( buffer, '=' ); // <key>[::space::]*=[::space::]*<value>
-                                                               
-                                                               if ( !p || ( p == ( buffer + 1 ))) // no = or key is empty
-                                                                       parse_error ( "malformed keyword" );
-                                                               
-                                                               l = p - buffer;
-                                                               while ( isspace ( buffer [--l] )) { } // skip whitespace
-                                                               
-                                                               buffer [l+1] = 0;
-                                                               
-                                                               if (( applet = find_applet_by_name ( buffer ))) {
-                                                                       struct BB_suid_config *sct = xmalloc ( sizeof( struct BB_suid_config ));
-                                                                       
-                                                                       sct-> m_applet = applet;
-                                                                       sct-> m_next = suid_config;
-                                                                       suid_config = sct;
-                                                                       
-                                                                       while ( isspace ( *++p )) { } // skip whitespace
-                                                                                               
-                                                                       sct-> m_mode = 0;                       
-                                                                       
-                                                                       switch ( *p++ ) {
-                                                                               case 'S': sct-> m_mode |= S_ISUID; break;
-                                                                               case 's': sct-> m_mode |= S_ISUID; // no break
-                                                                               case 'x': sct-> m_mode |= S_IXUSR; break;
-                                                                               case '-': break;
-                                                                               default : parse_error ( "invalid user mode" );
-                                                                       }
-                                                                               
-                                                                       switch ( *p++ ) {
-                                                                               case 's': sct-> m_mode |= S_ISGID; // no break
-                                                                               case 'x': sct-> m_mode |= S_IXGRP; break;
-                                                                               case 'S': break;
-                                                                               case '-': break;
-                                                                               default : parse_error ( "invalid group mode" );
-                                                                       }
-                                                                               
-                                                                       switch ( *p ) {
-                                                                               case 't': 
-                                                                               case 'x': sct-> m_mode |= S_IXOTH; break;
-                                                                               case 'T':
-                                                                               case '-': break;
-                                                                               default : parse_error ( "invalid other mode" );
-                                                                       }
-                                                                               
-                                                                       while ( isspace ( *++p )) { } // skip whitespace
-                                                                       
-                                                                       if ( isdigit ( *p )) {
-                                                                               sct-> m_uid = strtol ( p, &p, 10 );
-                                                                               if ( *p++ != '.' )
-                                                                                       parse_error ( "parsing <uid>.<gid>" );                                                                          
-                                                                       }
-                                                                       else {
-                                                                               struct passwd *pwd;
-                                                                               char *p2 = strchr ( p, '.' );
-                                                                               
-                                                                               if ( !p2 ) 
-                                                                                       parse_error ( "parsing <uid>.<gid>" );                                                                          
-       
-                                                                               *p2 = 0;
-                                                                               pwd = getpwnam ( p );
-                                               
-                                                                               if ( !pwd ) 
-                                                                                       parse_error ( "invalid user name" );
-                                                                               
-                                                                               sct-> m_uid = pwd-> pw_uid;
-                                                                               p = p2 + 1;
-                                                                       }               
-                                                                       if ( isdigit ( *p )) 
-                                                                               sct-> m_gid = strtol ( p, &p, 10 );
-                                                                       else {
-                                                                               struct group *grp = getgrnam ( p );
-                                               
-                                                                               if ( !grp ) 
-                                                                                       parse_error ( "invalid group name" );
-                                                                               
-                                                                               sct-> m_gid = grp-> gr_gid;
-                                                                       }                                                                                                                                               
-                                                               }
-                                                               break;
-                                                       }
-                                                       default: // unknown - skip
-                                                               break;
-                                               }                                       
-                                       }
-                                       else
-                                               parse_error ( "keyword not within section" );
-                               }                               
-                               fclose ( f );
-                       }
-               }
+       int input[2], output[2], pid;
+       char *buf;
+
+       if(pipe(input) < 0 || pipe(output) < 0)
+               exit(1);
+
+       pid = fork();
+       switch (pid) {
+       case -1: /* error */
+               exit(1);
+       case 0: /* child */
+               close(input[1]);
+               close(output[0]);
+               uncompressStream(input[0], output[1]);
+               exit(0);
        }
-       return 1;
-       
-pe_label:      
-       fprintf ( stderr, "Parse error in %s, line %d: %s\n", CONFIG_FILE, lc, err );
-
-       if ( f )
-               fclose ( f );
-       return 0;
+       /* parent */
+
+       close(input[0]);
+       close(output[1]);
+       pid = fork();
+       switch (pid) {
+       case -1: /* error */
+               exit(1);
+       case 0: /* child */
+               full_write(input[1], packed_usage, sizeof(packed_usage));
+               exit(0);
+       }
+       /* parent */
+       close(input[1]);
+
+       buf = xmalloc(SIZEOF_usage_messages);
+       full_read(output[0], buf, SIZEOF_usage_messages);
+       return buf;
 }
 
-#endif
+#else
+#define unpack_usage_messages() usage_messages
+#endif /* ENABLE_FEATURE_COMPRESS_USAGE */
 
-#endif
+void bb_show_usage (void)
+{
+       if (ENABLE_SHOW_USAGE) {
+               const char *format_string;
+               const char *usage_string = unpack_usage_messages();
+               int i;
+
+               for (i = applet_using - applets; i > 0;)
+                       if (!*usage_string++) --i;
+
+               format_string = "%s\n\nUsage: %s %s\n\n";
+               if (*usage_string == '\b')
+                       format_string = "%s\n\nNo help available.\n\n";
+               fprintf (stderr, format_string, bb_msg_full_version,
+                       applet_using->name, usage_string);
+       }
 
-/* END CODE */
-/*
-Local Variables:
-c-file-style: "linux"
-c-basic-offset: 4
-tab-width: 4
-End:
-*/
+  exit (bb_default_error_retval);
+}
+
+static int applet_name_compare(const void *name, const void *vapplet)
+{
+  const struct BB_applet *applet = vapplet;
+
+  return strcmp(name, applet->name);
+}
+
+extern const size_t NUM_APPLETS;
+
+struct BB_applet *find_applet_by_name(const char *name)
+{
+  return bsearch(name, applets, NUM_APPLETS, sizeof(struct BB_applet),
+                                 applet_name_compare);
+}
+
+void run_applet_by_name(const char *name, int argc, char **argv)
+{
+       if (ENABLE_FEATURE_SUID_CONFIG) parse_config_file();
+
+       if (!strncmp(name, "busybox", 7)) busybox_main(argc, argv);
+       /* Do a binary search to find the applet entry given the name. */
+       applet_using = find_applet_by_name(name);
+       if (applet_using) {
+               bb_applet_name = applet_using->name;
+               if(argc==2 && !strcmp(argv[1], "--help")) bb_show_usage();
+               if(ENABLE_FEATURE_SUID) check_suid(applet_using);
+               exit((*(applet_using->main))(argc, argv));
+       }
+}