libbusybox: move (possibly compressed) help stuff into libbusybox.

Makes individual binaries much smaller.

Config.in

@@ -283,14 +283,15 @@ config STATIC
 config BUILD_LIBBUSYBOX
 	bool "Build shared libbusybox"
 	default n
+	depends on !FEATURE_PREFER_APPLETS
 	help
-	  Build a shared library libbusybox.so which contains all
+	  Build a shared library libbusybox.so.N.N.N which contains all
-	  libraries used inside busybox.
+	  busybox code.
 
-	  This is an experimental feature intended to support the upcoming
+	  This feature allows every applet to be built as a tiny
-	  "make standalone" mode.  Enabling it against the one big busybox
+	  separate executable.  Enabling it for "one big busybox binary"
-	  binary serves no purpose (and increases the size).  You should
+	  approach serves no purpose and increases code size.
-	  almost certainly say "no" to this right now.
+	  You should almost certainly say "no" to this.
 
 ### config FEATURE_FULL_LIBBUSYBOX
 ###	bool "Feature-complete libbusybox"

applets/Kbuild

@@ -4,7 +4,7 @@
 #
 # Licensed under the GPL v2, see the file LICENSE in this tarball.
 
-obj-y:=
+obj-y :=
 obj-y += applets.o
 
 hostprogs-y:=

applets/applets.c

@@ -15,6 +15,7 @@
 #include <assert.h>
 #include "busybox.h"
 
+
 /* Apparently uclibc defines __GLIBC__ (compat trick?). Oh well. */
 #if ENABLE_STATIC && defined(__GLIBC__) && !defined(__UCLIBC__)
 #warning Static linking against glibc produces buggy executables
@@ -27,32 +28,8 @@
 #endif
 
 
-/* Declare <applet>_main() */
-#define PROTOTYPES
-#include "applets.h"
-#undef PROTOTYPES
-
-#if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
-/* Define usage_messages[] */
-static const char usage_messages[] ALIGN1 = ""
-#define MAKE_USAGE
-#include "usage.h"
-#include "applets.h"
-;
-#undef MAKE_USAGE
-#else
-#define usage_messages 0
-#endif /* SHOW_USAGE */
-
-/* Define struct bb_applet applets[] */
-#include "applets.h"
-/* The -1 arises because of the {0,NULL,0,-1} entry. */
-
-#if ENABLE_FEATURE_SH_STANDALONE
-const unsigned short NUM_APPLETS = ARRAY_SIZE(applets);
-#endif
 const struct bb_applet *current_applet;
-const char *applet_name ATTRIBUTE_EXTERNALLY_VISIBLE;
+const char *applet_name;
 #if !BB_MMU
 bool re_execed;
 #endif
@@ -419,82 +396,6 @@ static void check_suid(const struct bb_applet *applet)
 #endif /* FEATURE_SUID */
 
 
-#if ENABLE_FEATURE_COMPRESS_USAGE
-
-#include "usage_compressed.h"
-#include "unarchive.h"
-
-static const char *unpack_usage_messages(void)
-{
-	char *outbuf = NULL;
-	bunzip_data *bd;
-	int i;
-
-	i = start_bunzip(&bd,
-			/* src_fd: */ -1,
-			/* inbuf:  */ packed_usage,
-			/* len:    */ sizeof(packed_usage));
-	/* read_bunzip can longjmp to start_bunzip, and ultimately
-	 * end up here with i != 0 on read data errors! Not trivial */
-	if (!i) {
-		/* Cannot use xmalloc: will leak bd in NOFORK case! */
-		outbuf = malloc_or_warn(SIZEOF_usage_messages);
-		if (outbuf)
-			read_bunzip(bd, outbuf, SIZEOF_usage_messages);
-	}
-	dealloc_bunzip(bd);
-	return outbuf;
-}
-#define dealloc_usage_messages(s) free(s)
-
-#else
-
-#define unpack_usage_messages() usage_messages
-#define dealloc_usage_messages(s) ((void)(s))
-
-#endif /* FEATURE_COMPRESS_USAGE */
-
-
-void bb_show_usage(void)
-{
-	if (ENABLE_SHOW_USAGE) {
-		const char *format_string;
-		const char *p;
-		const char *usage_string = p = unpack_usage_messages();
-		int i;
-
-		i = current_applet - applets;
-		while (i) {
-			while (*p++) continue;
-			i--;
-		}
-
-		fprintf(stderr, "%s multi-call binary\n", bb_banner);
-		format_string = "\nUsage: %s %s\n\n";
-		if (*p == '\b')
-			format_string = "\nNo help available.\n\n";
-		fprintf(stderr, format_string, applet_name, p);
-		dealloc_usage_messages((char*)usage_string);
-	}
-	xfunc_die();
-}
-
-
-static int applet_name_compare(const void *name, const void *vapplet)
-{
-	const struct bb_applet *applet = vapplet;
-
-	return strcmp(name, applet->name);
-}
-
-const struct bb_applet *find_applet_by_name(const char *name)
-{
-	/* Do a binary search to find the applet entry given the name. */
-	return bsearch(name, applets, ARRAY_SIZE(applets)-1, sizeof(applets[0]),
-				applet_name_compare);
-}
-
-
 #if ENABLE_FEATURE_INSTALLER
 /* create (sym)links for each applet */
 static void install_links(const char *busybox, int use_symbolic_links)
@@ -635,16 +536,9 @@ void run_applet_and_exit(const char *name, char **argv)
 }
 
 
-#ifdef __GLIBC__
-/* Make it reside in R/W memory: */
-int *const bb_errno __attribute__ ((section (".data")));
-#endif
-
 int main(int argc, char **argv)
 {
-#ifdef __GLIBC__
+	bbox_prepare_main();
-	(*(int **)&bb_errno) = __errno_location();
-#endif
 
 #if !BB_MMU
 	/* NOMMU re-exec trick sets high-order bit in first byte of name */
@@ -660,10 +554,6 @@ int main(int argc, char **argv)
 
 	parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
 
-	/* Set locale for everybody except 'init' */
-	if (ENABLE_LOCALE_SUPPORT && getpid() != 1)
-		setlocale(LC_ALL, "");
-
 	run_applet_and_exit(applet_name, argv);
 	bb_error_msg_and_die("applet not found");
 }

include/busybox.h

@@ -48,8 +48,9 @@ struct bb_applet {
 #endif
 };
 
-/* Defined in applet.c */
+/* Defined in appletlib.c */
 extern const struct bb_applet applets[];
 extern const unsigned short NUM_APPLETS;
+void bbox_prepare_main(void);
 
 #endif	/* _BB_INTERNAL_H_ */

libbb/Kbuild

@@ -6,6 +6,7 @@
 
 lib-y:=
 
+lib-y += appletlib.o
 lib-y += ask_confirmation.o
 lib-y += bb_askpass.o
 lib-y += bb_basename.o

scripts/trylink

@@ -128,6 +128,7 @@ if test "$CONFIG_BUILD_LIBBUSYBOX" = y; then
 	exit 1
     }
     strip -s --remove-section=.note --remove-section=.comment $EXE -o "$sharedlib_dir/libbusybox.so.$BB_VER"
+    chmod a+x "$sharedlib_dir/libbusybox.so.$BB_VER"
     echo "libbusybox: $sharedlib_dir/libbusybox.so.$BB_VER"
 fi
 
@@ -160,40 +161,14 @@ if test "$CONFIG_FEATURE_INDIVIDUAL" = y; then
 	test x"$cname" = "x[[" && cname=test
 
 	echo "\
-#include <errno.h>
+void bbox_prepare_main(void);
-#include <unistd.h>
+int $main(int argc, char **argv);
-#include <stdlib.h>
-#include <stdio.h>
-#include \"../include/autoconf.h\"
-#include \"../include/usage.h\"
-
-#ifdef __GLIBC__
-/* Make it reside in R/W memory: */
-int *const bb_errno __attribute__ ((section (\".data\")));
-#endif
 
 const char *applet_name = \"$name\";
 
-void bb_show_usage(void)
-{
-	fprintf(stderr, \"Usage: $name \"
-#ifdef ${cname}_trivial_usage
-		${cname}_trivial_usage
-#endif
-#ifdef ${cname}_full_usage
-		\"\\n\\n\" ${cname}_full_usage
-#endif
-		\"\\n\\n\");
-	exit(1);
-}
-
-int $main(int argc, char **argv);
-
 int main(int argc, char **argv)
 {
-#ifdef __GLIBC__
+	bbox_prepare_main();
-        (*(int **)&bb_errno) = __errno_location();
-#endif
 	return $main(argc, argv);
 }
 " >"$sharedlib_dir/applet.c"
@@ -215,3 +190,7 @@ int main(int argc, char **argv)
 
     done <applet.lst
 fi
+
+# libbusybox.so is needed only for -lbusybox at link time,
+# it is not needed at runtime. Deleting to reduce confusion.
+rm "$sharedlib_dir"/libbusybox.so >/dev/null