816 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			816 lines
		
	
	
		
			21 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* vi: set sw=4 ts=4: */
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| /*
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|  * Utility routines.
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|  *
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|  * Copyright (C) tons of folks.  Tracking down who wrote what
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|  * isn't something I'm going to worry about...  If you wrote something
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|  * here, please feel free to acknowledge your work.
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|  *
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|  * Based in part on code from sash, Copyright (c) 1999 by David I. Bell
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|  * Permission has been granted to redistribute this code under the GPL.
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|  *
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|  * Licensed under GPLv2 or later, see file License in this tarball for details.
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|  */
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| 
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| /* We are trying to not use printf, this benefits the case when selected
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|  * applets are really simple. Example:
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|  *
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|  * $ ./busybox
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|  * ...
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|  * Currently defined functions:
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|  *         basename, false, true
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|  *
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|  * $ size busybox
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|  *    text    data     bss     dec     hex filename
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|  *    4473      52      72    4597    11f5 busybox
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|  *
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|  * FEATURE_INSTALLER or FEATURE_SUID will still link printf routines in. :(
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|  */
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| 
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| #include "busybox.h"
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| #include <assert.h>
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| #include <malloc.h>
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| #include <sys/user.h> /* PAGE_SIZE */
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| 
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| 
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| /* Declare <applet>_main() */
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| #define PROTOTYPES
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| #include "applets.h"
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| #undef PROTOTYPES
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| 
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| #if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
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| /* Define usage_messages[] */
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| static const char usage_messages[] ALIGN1 = ""
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| #define MAKE_USAGE
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| #include "usage.h"
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| #include "applets.h"
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| ;
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| #undef MAKE_USAGE
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| #else
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| #define usage_messages 0
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| #endif /* SHOW_USAGE */
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| 
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| 
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| /* Include generated applet names, pointers to <applet>_main, etc */
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| #include "applet_tables.h"
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| /* ...and if applet_tables generator says we have only one applet... */
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| #ifdef SINGLE_APPLET_MAIN
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| #undef ENABLE_FEATURE_INDIVIDUAL
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| #define ENABLE_FEATURE_INDIVIDUAL 1
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| #undef IF_FEATURE_INDIVIDUAL
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| #define IF_FEATURE_INDIVIDUAL(...) __VA_ARGS__
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| #endif
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| 
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| 
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| #if ENABLE_FEATURE_COMPRESS_USAGE
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| 
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| #include "usage_compressed.h"
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| #include "unarchive.h"
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| 
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| static const char *unpack_usage_messages(void)
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| {
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| 	char *outbuf = NULL;
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| 	bunzip_data *bd;
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| 	int i;
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| 
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| 	i = start_bunzip(&bd,
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| 			/* src_fd: */ -1,
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| 			/* inbuf:  */ (void *)packed_usage,
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| 			/* len:    */ sizeof(packed_usage));
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| 	/* read_bunzip can longjmp to start_bunzip, and ultimately
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| 	 * end up here with i != 0 on read data errors! Not trivial */
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| 	if (!i) {
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| 		/* Cannot use xmalloc: will leak bd in NOFORK case! */
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| 		outbuf = malloc_or_warn(SIZEOF_usage_messages);
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| 		if (outbuf)
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| 			read_bunzip(bd, outbuf, SIZEOF_usage_messages);
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| 	}
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| 	dealloc_bunzip(bd);
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| 	return outbuf;
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| }
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| #define dealloc_usage_messages(s) free(s)
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| 
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| #else
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| 
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| #define unpack_usage_messages() usage_messages
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| #define dealloc_usage_messages(s) ((void)(s))
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| 
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| #endif /* FEATURE_COMPRESS_USAGE */
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| 
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| 
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| static void full_write2_str(const char *str)
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| {
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| 	xwrite_str(STDERR_FILENO, str);
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| }
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| 
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| void FAST_FUNC bb_show_usage(void)
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| {
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| 	if (ENABLE_SHOW_USAGE) {
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| #ifdef SINGLE_APPLET_STR
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| 		/* Imagine that this applet is "true". Dont suck in printf! */
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| 		const char *p;
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| 		const char *usage_string = p = unpack_usage_messages();
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| 
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| 		if (*p == '\b') {
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| 			full_write2_str("No help available.\n\n");
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| 		} else {
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| 			full_write2_str("Usage: "SINGLE_APPLET_STR" ");
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| 			full_write2_str(p);
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| 			full_write2_str("\n\n");
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| 		}
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| 		if (ENABLE_FEATURE_CLEAN_UP)
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| 			dealloc_usage_messages((char*)usage_string);
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| #else
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| 		const char *p;
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| 		const char *usage_string = p = unpack_usage_messages();
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| 		int ap = find_applet_by_name(applet_name);
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| 
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| 		if (ap < 0) /* never happens, paranoia */
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| 			xfunc_die();
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| 		while (ap) {
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| 			while (*p++) continue;
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| 			ap--;
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| 		}
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| 		full_write2_str(bb_banner);
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| 		full_write2_str(" multi-call binary.\n");
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| 		if (*p == '\b')
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| 			full_write2_str("\nNo help available.\n\n");
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| 		else {
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| 			full_write2_str("\nUsage: ");
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| 			full_write2_str(applet_name);
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| 			full_write2_str(" ");
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| 			full_write2_str(p);
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| 			full_write2_str("\n\n");
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| 		}
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| 		if (ENABLE_FEATURE_CLEAN_UP)
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| 			dealloc_usage_messages((char*)usage_string);
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| #endif
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| 	}
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| 	xfunc_die();
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| }
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| 
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| #if NUM_APPLETS > 8
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| /* NB: any char pointer will work as well, not necessarily applet_names */
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| static int applet_name_compare(const void *name, const void *v)
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| {
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| 	int i = (const char *)v - applet_names;
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| 	return strcmp(name, APPLET_NAME(i));
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| }
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| #endif
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| int FAST_FUNC find_applet_by_name(const char *name)
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| {
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| #if NUM_APPLETS > 8
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| 	/* Do a binary search to find the applet entry given the name. */
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| 	const char *p;
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| 	p = bsearch(name, applet_names, ARRAY_SIZE(applet_main), 1, applet_name_compare);
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| 	if (!p)
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| 		return -1;
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| 	return p - applet_names;
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| #else
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| 	/* A version which does not pull in bsearch */
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| 	int i = 0;
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| 	const char *p = applet_names;
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| 	while (i < NUM_APPLETS) {
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| 		if (strcmp(name, p) == 0)
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| 			return i;
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| 		p += strlen(p) + 1;
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| 		i++;
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| 	}
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| 	return -1;
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| #endif
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| }
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| 
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| 
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| void lbb_prepare(const char *applet
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| 		IF_FEATURE_INDIVIDUAL(, char **argv))
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| 				MAIN_EXTERNALLY_VISIBLE;
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| void lbb_prepare(const char *applet
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| 		IF_FEATURE_INDIVIDUAL(, char **argv))
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| {
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| #ifdef __GLIBC__
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| 	(*(int **)&bb_errno) = __errno_location();
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| 	barrier();
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| #endif
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| 	applet_name = applet;
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| 
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| 	/* Set locale for everybody except 'init' */
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| 	if (ENABLE_LOCALE_SUPPORT && getpid() != 1)
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| 		setlocale(LC_ALL, "");
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| 
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| #if ENABLE_FEATURE_INDIVIDUAL
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| 	/* Redundant for busybox (run_applet_and_exit covers that case)
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| 	 * but needed for "individual applet" mode */
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| 	if (argv[1] && !argv[2] && strcmp(argv[1], "--help") == 0) {
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| 		/* Special case. POSIX says "test --help"
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| 		 * should be no different from e.g. "test --foo".  */
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| 		if (!ENABLE_TEST || strcmp(applet_name, "test") != 0)
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| 			bb_show_usage();
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| 	}
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| #endif
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| }
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| 
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| /* The code below can well be in applets/applets.c, as it is used only
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|  * for busybox binary, not "individual" binaries.
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|  * However, keeping it here and linking it into libbusybox.so
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|  * (together with remaining tiny applets/applets.o)
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|  * makes it possible to avoid --whole-archive at link time.
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|  * This makes (shared busybox) + libbusybox smaller.
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|  * (--gc-sections would be even better....)
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|  */
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| 
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| const char *applet_name;
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| #if !BB_MMU
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| bool re_execed;
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| #endif
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| 
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| 
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| /* If not built as a single-applet executable... */
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| #if !defined(SINGLE_APPLET_MAIN)
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| 
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| IF_FEATURE_SUID(static uid_t ruid;)  /* real uid */
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| 
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| #if ENABLE_FEATURE_SUID_CONFIG
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| 
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| /* applets[] is const, so we have to define this "override" structure */
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| static struct BB_suid_config {
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| 	int m_applet;
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| 	uid_t m_uid;
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| 	gid_t m_gid;
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| 	mode_t m_mode;
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| 	struct BB_suid_config *m_next;
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| } *suid_config;
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| 
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| static bool suid_cfg_readable;
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| 
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| /* check if u is member of group g */
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| static int ingroup(uid_t u, gid_t g)
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| {
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| 	struct group *grp = getgrgid(g);
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| 
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| 	if (grp) {
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| 		char **mem;
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| 
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| 		for (mem = grp->gr_mem; *mem; mem++) {
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| 			struct passwd *pwd = getpwnam(*mem);
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| 
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| 			if (pwd && (pwd->pw_uid == u))
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| 				return 1;
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| 		}
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| 	}
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| 	return 0;
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| }
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| 
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| /* This should probably be a libbb routine.  In that case,
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|  * I'd probably rename it to something like bb_trimmed_slice.
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|  */
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| static char *get_trimmed_slice(char *s, char *e)
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| {
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| 	/* First, consider the value at e to be nul and back up until we
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| 	 * reach a non-space char.  Set the char after that (possibly at
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| 	 * the original e) to nul. */
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| 	while (e-- > s) {
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| 		if (!isspace(*e)) {
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| 			break;
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| 		}
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| 	}
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| 	e[1] = '\0';
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| 
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| 	/* Next, advance past all leading space and return a ptr to the
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| 	 * first non-space char; possibly the terminating nul. */
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| 	return skip_whitespace(s);
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| }
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| 
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| /* Don't depend on the tools to combine strings. */
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| static const char config_file[] ALIGN1 = "/etc/busybox.conf";
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| 
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| /* We don't supply a value for the nul, so an index adjustment is
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|  * necessary below.  Also, we use unsigned short here to save some
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|  * space even though these are really mode_t values. */
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| static const unsigned short mode_mask[] ALIGN2 = {
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| 	/*  SST     sst                 xxx         --- */
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| 	S_ISUID,    S_ISUID|S_IXUSR,    S_IXUSR,    0,	/* user */
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| 	S_ISGID,    S_ISGID|S_IXGRP,    S_IXGRP,    0,	/* group */
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| 	0,          S_IXOTH,            S_IXOTH,    0	/* other */
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| };
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| 
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| #define parse_error(x)  do { errmsg = x; goto pe_label; } while (0)
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| 
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| static void parse_config_file(void)
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| {
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| 	struct BB_suid_config *sct_head;
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| 	struct BB_suid_config *sct;
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| 	int applet_no;
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| 	FILE *f;
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| 	const char *errmsg;
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| 	char *s;
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| 	char *e;
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| 	int i;
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| 	unsigned lc;
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| 	smallint section;
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| 	char buffer[256];
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| 	struct stat st;
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| 
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| 	assert(!suid_config); /* Should be set to NULL by bss init. */
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| 
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| 	ruid = getuid();
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| 	if (ruid == 0) /* run by root - don't need to even read config file */
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| 		return;
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| 
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| 	if ((stat(config_file, &st) != 0)       /* No config file? */
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| 	 || !S_ISREG(st.st_mode)                /* Not a regular file? */
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| 	 || (st.st_uid != 0)                    /* Not owned by root? */
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| 	 || (st.st_mode & (S_IWGRP | S_IWOTH))  /* Writable by non-root? */
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| 	 || !(f = fopen_for_read(config_file))      /* Cannot open? */
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| 	) {
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| 		return;
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| 	}
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| 
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| 	suid_cfg_readable = 1;
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| 	sct_head = NULL;
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| 	section = lc = 0;
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| 
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| 	while (1) {
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| 		s = buffer;
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| 
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| 		if (!fgets(s, sizeof(buffer), f)) { /* Are we done? */
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| // why?
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| 			if (ferror(f)) {   /* Make sure it wasn't a read error. */
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| 				parse_error("reading");
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| 			}
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| 			fclose(f);
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| 			suid_config = sct_head;	/* Success, so set the pointer. */
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| 			return;
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| 		}
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| 
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| 		lc++;					/* Got a (partial) line. */
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| 
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| 		/* If a line is too long for our buffer, we consider it an error.
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| 		 * The following test does mistreat one corner case though.
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| 		 * If the final line of the file does not end with a newline and
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| 		 * yet exactly fills the buffer, it will be treated as too long
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| 		 * even though there isn't really a problem.  But it isn't really
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| 		 * worth adding code to deal with such an unlikely situation, and
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| 		 * we do err on the side of caution.  Besides, the line would be
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| 		 * too long if it did end with a newline. */
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| 		if (!strchr(s, '\n') && !feof(f)) {
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| 			parse_error("line too long");
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| 		}
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| 
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| 		/* Trim leading and trailing whitespace, ignoring comments, and
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| 		 * check if the resulting string is empty. */
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| 		s = get_trimmed_slice(s, strchrnul(s, '#'));
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| 		if (!*s) {
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| 			continue;
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| 		}
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| 
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| 		/* Check for a section header. */
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| 
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| 		if (*s == '[') {
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| 			/* Unlike the old code, we ignore leading and trailing
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| 			 * whitespace for the section name.  We also require that
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| 			 * there are no stray characters after the closing bracket. */
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| 			e = strchr(s, ']');
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| 			if (!e   /* Missing right bracket? */
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| 			 || e[1] /* Trailing characters? */
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| 			 || !*(s = get_trimmed_slice(s+1, e)) /* Missing name? */
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| 			) {
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| 				parse_error("section header");
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| 			}
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| 			/* Right now we only have one section so just check it.
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| 			 * If more sections are added in the future, please don't
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| 			 * resort to cascading ifs with multiple strcasecmp calls.
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| 			 * That kind of bloated code is all too common.  A loop
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| 			 * and a string table would be a better choice unless the
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| 			 * number of sections is very small. */
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| 			if (strcasecmp(s, "SUID") == 0) {
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| 				section = 1;
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| 				continue;
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| 			}
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| 			section = -1;	/* Unknown section so set to skip. */
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| 			continue;
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| 		}
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| 
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| 		/* Process sections. */
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| 
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| 		if (section == 1) {		/* SUID */
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| 			/* Since we trimmed leading and trailing space above, we're
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| 			 * now looking for strings of the form
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| 			 *    <key>[::space::]*=[::space::]*<value>
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| 			 * where both key and value could contain inner whitespace. */
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| 
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| 			/* First get the key (an applet name in our case). */
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| 			e = strchr(s, '=');
 | |
| 			if (e) {
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| 				s = get_trimmed_slice(s, e);
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| 			}
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| 			if (!e || !*s) {	/* Missing '=' or empty key. */
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| 				parse_error("keyword");
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| 			}
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| 
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| 			/* Ok, we have an applet name.  Process the rhs if this
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| 			 * applet is currently built in and ignore it otherwise.
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| 			 * Note: this can hide config file bugs which only pop
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| 			 * up when the busybox configuration is changed. */
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| 			applet_no = find_applet_by_name(s);
 | |
| 			if (applet_no >= 0) {
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| 				/* Note: We currently don't check for duplicates!
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| 				 * The last config line for each applet will be the
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| 				 * one used since we insert at the head of the list.
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| 				 * I suppose this could be considered a feature. */
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| 				sct = xmalloc(sizeof(struct BB_suid_config));
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| 				sct->m_applet = applet_no;
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| 				sct->m_mode = 0;
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| 				sct->m_next = sct_head;
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| 				sct_head = sct;
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| 
 | |
| 				/* Get the specified mode. */
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| 
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| 				e = skip_whitespace(e+1);
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| 
 | |
| 				for (i = 0; i < 3; i++) {
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| 					/* There are 4 chars + 1 nul for each of user/group/other. */
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| 					static const char mode_chars[] ALIGN1 = "Ssx-\0" "Ssx-\0" "Ttx-";
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| 
 | |
| 					const char *q;
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| 					q = strchrnul(mode_chars + 5*i, *e++);
 | |
| 					if (!*q) {
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| 						parse_error("mode");
 | |
| 					}
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| 					/* 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
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| 				 * user/group info. */
 | |
| 				if ((s == e) || !(e = strchr(s, '.'))) {
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| 					parse_error("<uid>.<gid>");
 | |
| 				}
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| 				*e++ = '\0';
 | |
| 
 | |
| 				/* We can't use get_ug_id here since it would exit()
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| 				 * if a uid or gid was not found.  Oh well... */
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| 				sct->m_uid = bb_strtoul(s, NULL, 10);
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| 				if (errno) {
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| 					struct passwd *pwd = getpwnam(s);
 | |
| 					if (!pwd) {
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| 						parse_error("user");
 | |
| 					}
 | |
| 					sct->m_uid = pwd->pw_uid;
 | |
| 				}
 | |
| 
 | |
| 				sct->m_gid = bb_strtoul(e, NULL, 10);
 | |
| 				if (errno) {
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| 					struct group *grp;
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| 					grp = getgrnam(e);
 | |
| 					if (!grp) {
 | |
| 						parse_error("group");
 | |
| 					}
 | |
| 					sct->m_gid = grp->gr_gid;
 | |
| 				}
 | |
| 			}
 | |
| 			continue;
 | |
| 		}
 | |
| 
 | |
| 		/* Unknown sections are ignored. */
 | |
| 
 | |
| 		/* Encountering configuration lines prior to seeing a
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| 		 * section header is treated as an error.  This is how
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| 		 * the old code worked, but it may not be desirable.
 | |
| 		 * We may want to simply ignore such lines in case they
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| 		 * 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, errmsg);
 | |
| 
 | |
| 	fclose(f);
 | |
| 	/* Release any allocated memory before returning. */
 | |
| 	while (sct_head) {
 | |
| 		sct = sct_head->m_next;
 | |
| 		free(sct_head);
 | |
| 		sct_head = sct;
 | |
| 	}
 | |
| }
 | |
| #else
 | |
| static inline void parse_config_file(void)
 | |
| {
 | |
| 	IF_FEATURE_SUID(ruid = getuid();)
 | |
| }
 | |
| #endif /* FEATURE_SUID_CONFIG */
 | |
| 
 | |
| 
 | |
| #if ENABLE_FEATURE_SUID
 | |
| static void check_suid(int applet_no)
 | |
| {
 | |
| 	gid_t rgid;  /* real gid */
 | |
| 
 | |
| 	if (ruid == 0) /* set by parse_config_file() */
 | |
| 		return; /* run by root - no need to check more */
 | |
| 	rgid = getgid();
 | |
| 
 | |
| #if ENABLE_FEATURE_SUID_CONFIG
 | |
| 	if (suid_cfg_readable) {
 | |
| 		uid_t uid;
 | |
| 		struct BB_suid_config *sct;
 | |
| 		mode_t m;
 | |
| 
 | |
| 		for (sct = suid_config; sct; sct = sct->m_next) {
 | |
| 			if (sct->m_applet == applet_no)
 | |
| 				goto found;
 | |
| 		}
 | |
| 		goto check_need_suid;
 | |
|  found:
 | |
| 		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!");
 | |
| 
 | |
| 		/* _both_ sgid and group_exec have to be set for setegid */
 | |
| 		if ((sct->m_mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP))
 | |
| 			rgid = sct->m_gid;
 | |
| 		/* else (no setegid) we will set egid = rgid */
 | |
| 
 | |
| 		/* We set effective AND saved ids. If saved-id is not set
 | |
| 		 * like we do below, seteiud(0) can still later succeed! */
 | |
| 		if (setresgid(-1, rgid, rgid))
 | |
| 			bb_perror_msg_and_die("setresgid");
 | |
| 
 | |
| 		/* do we have to set effective uid? */
 | |
| 		uid = ruid;
 | |
| 		if (sct->m_mode & S_ISUID)
 | |
| 			uid = sct->m_uid;
 | |
| 		/* else (no seteuid) we will set euid = ruid */
 | |
| 
 | |
| 		if (setresuid(-1, uid, uid))
 | |
| 			bb_perror_msg_and_die("setresuid");
 | |
| 		return;
 | |
| 	}
 | |
| #if !ENABLE_FEATURE_SUID_CONFIG_QUIET
 | |
| 	{
 | |
| 		static bool onetime = 0;
 | |
| 
 | |
| 		if (!onetime) {
 | |
| 			onetime = 1;
 | |
| 			fprintf(stderr, "Using fallback suid method\n");
 | |
| 		}
 | |
| 	}
 | |
| #endif
 | |
|  check_need_suid:
 | |
| #endif
 | |
| 	if (APPLET_SUID(applet_no) == _BB_SUID_REQUIRE) {
 | |
| 		/* Real uid is not 0. If euid isn't 0 too, suid bit
 | |
| 		 * is most probably not set on our executable */
 | |
| 		if (geteuid())
 | |
| 			bb_error_msg_and_die("must be suid to work properly");
 | |
| 	} else if (APPLET_SUID(applet_no) == _BB_SUID_DROP) {
 | |
| 		xsetgid(rgid);  /* drop all privileges */
 | |
| 		xsetuid(ruid);
 | |
| 	}
 | |
| }
 | |
| #else
 | |
| #define check_suid(x) ((void)0)
 | |
| #endif /* FEATURE_SUID */
 | |
| 
 | |
| 
 | |
| #if ENABLE_FEATURE_INSTALLER
 | |
| /* create (sym)links for each applet */
 | |
| static void install_links(const char *busybox, int use_symbolic_links,
 | |
| 		char *custom_install_dir)
 | |
| {
 | |
| 	/* directory table
 | |
| 	 * this should be consistent w/ the enum,
 | |
| 	 * busybox.h::bb_install_loc_t, or else... */
 | |
| 	static const char usr_bin [] ALIGN1 = "/usr/bin";
 | |
| 	static const char usr_sbin[] ALIGN1 = "/usr/sbin";
 | |
| 	static const char *const install_dir[] = {
 | |
| 		&usr_bin [8], /* "", equivalent to "/" for concat_path_file() */
 | |
| 		&usr_bin [4], /* "/bin" */
 | |
| 		&usr_sbin[4], /* "/sbin" */
 | |
| 		usr_bin,
 | |
| 		usr_sbin
 | |
| 	};
 | |
| 
 | |
| 	int (*lf)(const char *, const char *);
 | |
| 	char *fpc;
 | |
| 	unsigned i;
 | |
| 	int rc;
 | |
| 
 | |
| 	lf = link;
 | |
| 	if (use_symbolic_links)
 | |
| 		lf = symlink;
 | |
| 
 | |
| 	for (i = 0; i < ARRAY_SIZE(applet_main); i++) {
 | |
| 		fpc = concat_path_file(
 | |
| 				custom_install_dir ? custom_install_dir : install_dir[APPLET_INSTALL_LOC(i)],
 | |
| 				APPLET_NAME(i));
 | |
| 		// debug: bb_error_msg("%slinking %s to busybox",
 | |
| 		//		use_symbolic_links ? "sym" : "", fpc);
 | |
| 		rc = lf(busybox, fpc);
 | |
| 		if (rc != 0 && errno != EEXIST) {
 | |
| 			bb_simple_perror_msg(fpc);
 | |
| 		}
 | |
| 		free(fpc);
 | |
| 	}
 | |
| }
 | |
| #else
 | |
| #define install_links(x,y,z) ((void)0)
 | |
| #endif /* FEATURE_INSTALLER */
 | |
| 
 | |
| /* If we were called as "busybox..." */
 | |
| static int busybox_main(char **argv)
 | |
| {
 | |
| 	if (!argv[1]) {
 | |
| 		/* Called without arguments */
 | |
| 		const char *a;
 | |
| 		int col;
 | |
| 		unsigned output_width;
 | |
|  help:
 | |
| 		output_width = 80;
 | |
| 		if (ENABLE_FEATURE_AUTOWIDTH) {
 | |
| 			/* Obtain the terminal width */
 | |
| 			get_terminal_width_height(0, &output_width, NULL);
 | |
| 		}
 | |
| 
 | |
| 		dup2(1, 2);
 | |
| 		full_write2_str(bb_banner); /* reuse const string */
 | |
| 		full_write2_str(" multi-call binary.\n"); /* reuse */
 | |
| 		full_write2_str(
 | |
| 		       "Copyright (C) 1998-2009 Erik Andersen, Rob Landley, Denys Vlasenko\n"
 | |
| 		       "and others. Licensed under GPLv2.\n"
 | |
| 		       "See source distribution for full notice.\n"
 | |
| 		       "\n"
 | |
| 		       "Usage: busybox [function] [arguments]...\n"
 | |
| 		       "   or: function [arguments]...\n"
 | |
| 		       "\n"
 | |
| 		       "\tBusyBox is a multi-call binary that combines many common Unix\n"
 | |
| 		       "\tutilities into a single executable.  Most people will create a\n"
 | |
| 		       "\tlink to busybox for each function they wish to use and BusyBox\n"
 | |
| 		       "\twill act like whatever it was invoked as.\n"
 | |
| 		       "\n"
 | |
| 		       "Currently defined functions:\n");
 | |
| 		col = 0;
 | |
| 		a = applet_names;
 | |
| 		/* prevent last comma to be in the very last pos */
 | |
| 		output_width--;
 | |
| 		while (*a) {
 | |
| 			int len2 = strlen(a) + 2;
 | |
| 			if (col >= (int)output_width - len2) {
 | |
| 				full_write2_str(",\n");
 | |
| 				col = 0;
 | |
| 			}
 | |
| 			if (col == 0) {
 | |
| 				col = 6;
 | |
| 				full_write2_str("\t");
 | |
| 			} else {
 | |
| 				full_write2_str(", ");
 | |
| 			}
 | |
| 			full_write2_str(a);
 | |
| 			col += len2;
 | |
| 			a += len2 - 1;
 | |
| 		}
 | |
| 		full_write2_str("\n\n");
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	if (ENABLE_FEATURE_INSTALLER && strcmp(argv[1], "--install") == 0) {
 | |
| 		int use_symbolic_links;
 | |
| 		const char *busybox;
 | |
| 		busybox = xmalloc_readlink(bb_busybox_exec_path);
 | |
| 		if (!busybox)
 | |
| 			busybox = bb_busybox_exec_path;
 | |
| 		/* busybox --install [-s] [DIR]: */
 | |
| 		/* -s: make symlinks */
 | |
| 		/* DIR: directory to install links to */
 | |
| 		use_symbolic_links = (argv[2] && strcmp(argv[2], "-s") == 0 && argv++);
 | |
| 		install_links(busybox, use_symbolic_links, argv[2]);
 | |
| 		return 0;
 | |
| 	}
 | |
| 
 | |
| 	if (strcmp(argv[1], "--help") == 0) {
 | |
| 		/* "busybox --help [<applet>]" */
 | |
| 		if (!argv[2])
 | |
| 			goto help;
 | |
| 		/* convert to "<applet> --help" */
 | |
| 		argv[0] = argv[2];
 | |
| 		argv[2] = NULL;
 | |
| 	} else {
 | |
| 		/* "busybox <applet> arg1 arg2 ..." */
 | |
| 		argv++;
 | |
| 	}
 | |
| 	/* We support "busybox /a/path/to/applet args..." too. Allows for
 | |
| 	 * "#!/bin/busybox"-style wrappers */
 | |
| 	applet_name = bb_get_last_path_component_nostrip(argv[0]);
 | |
| 	run_applet_and_exit(applet_name, argv);
 | |
| 
 | |
| 	/*bb_error_msg_and_die("applet not found"); - sucks in printf */
 | |
| 	full_write2_str(applet_name);
 | |
| 	full_write2_str(": applet not found\n");
 | |
| 	xfunc_die();
 | |
| }
 | |
| 
 | |
| void FAST_FUNC run_applet_no_and_exit(int applet_no, char **argv)
 | |
| {
 | |
| 	int argc = 1;
 | |
| 
 | |
| 	while (argv[argc])
 | |
| 		argc++;
 | |
| 
 | |
| 	/* Reinit some shared global data */
 | |
| 	xfunc_error_retval = EXIT_FAILURE;
 | |
| 
 | |
| 	applet_name = APPLET_NAME(applet_no);
 | |
| 	if (argc == 2 && strcmp(argv[1], "--help") == 0) {
 | |
| 		/* Special case. POSIX says "test --help"
 | |
| 		 * should be no different from e.g. "test --foo".  */
 | |
| //TODO: just compare applet_no with APPLET_NO_test
 | |
| 		if (!ENABLE_TEST || strcmp(applet_name, "test") != 0)
 | |
| 			bb_show_usage();
 | |
| 	}
 | |
| 	if (ENABLE_FEATURE_SUID)
 | |
| 		check_suid(applet_no);
 | |
| 	exit(applet_main[applet_no](argc, argv));
 | |
| }
 | |
| 
 | |
| void FAST_FUNC run_applet_and_exit(const char *name, char **argv)
 | |
| {
 | |
| 	int applet = find_applet_by_name(name);
 | |
| 	if (applet >= 0)
 | |
| 		run_applet_no_and_exit(applet, argv);
 | |
| 	if (!strncmp(name, "busybox", 7))
 | |
| 		exit(busybox_main(argv));
 | |
| }
 | |
| 
 | |
| #endif /* !defined(SINGLE_APPLET_MAIN) */
 | |
| 
 | |
| 
 | |
| 
 | |
| #if ENABLE_BUILD_LIBBUSYBOX
 | |
| int lbb_main(char **argv)
 | |
| #else
 | |
| int main(int argc UNUSED_PARAM, char **argv)
 | |
| #endif
 | |
| {
 | |
| 	/* Tweak malloc for reduced memory consumption */
 | |
| #ifndef PAGE_SIZE
 | |
| # define PAGE_SIZE (4*1024) /* guess */
 | |
| #endif
 | |
| #ifdef M_TRIM_THRESHOLD
 | |
| 	/* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory
 | |
| 	 * to keep before releasing to the OS
 | |
| 	 * Default is way too big: 256k
 | |
| 	 */
 | |
| 	mallopt(M_TRIM_THRESHOLD, 2 * PAGE_SIZE);
 | |
| #endif
 | |
| #ifdef M_MMAP_THRESHOLD
 | |
| 	/* M_MMAP_THRESHOLD is the request size threshold for using mmap()
 | |
| 	 * Default is too big: 256k
 | |
| 	 */
 | |
| 	mallopt(M_MMAP_THRESHOLD, 8 * PAGE_SIZE - 256);
 | |
| #endif
 | |
| 
 | |
| #if defined(SINGLE_APPLET_MAIN)
 | |
| 	/* Only one applet is selected by the user! */
 | |
| 	/* applet_names in this case is just "applet\0\0" */
 | |
| 	lbb_prepare(applet_names IF_FEATURE_INDIVIDUAL(, argv));
 | |
| 	return SINGLE_APPLET_MAIN(argc, argv);
 | |
| #else
 | |
| 	lbb_prepare("busybox" IF_FEATURE_INDIVIDUAL(, argv));
 | |
| 
 | |
| #if !BB_MMU
 | |
| 	/* NOMMU re-exec trick sets high-order bit in first byte of name */
 | |
| 	if (argv[0][0] & 0x80) {
 | |
| 		re_execed = 1;
 | |
| 		argv[0][0] &= 0x7f;
 | |
| 	}
 | |
| #endif
 | |
| 	applet_name = argv[0];
 | |
| 	if (applet_name[0] == '-')
 | |
| 		applet_name++;
 | |
| 	applet_name = bb_basename(applet_name);
 | |
| 
 | |
| 	parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
 | |
| 
 | |
| 	run_applet_and_exit(applet_name, argv);
 | |
| 
 | |
| 	/*bb_error_msg_and_die("applet not found"); - sucks in printf */
 | |
| 	full_write2_str(applet_name);
 | |
| 	full_write2_str(": applet not found\n");
 | |
| 	xfunc_die();
 | |
| #endif
 | |
| }
 |