ash: allow shell scripts to be embedded in the binary
To assist in the deployment of shell scripts it may be convenient
to embed them in the BusyBox binary.
'Embed scripts in the binary' takes any files in the directory
'embed', concatenates them with null separators, compresses them
and embeds them in the binary.
When scripts are embedded in the binary, scripts can be run as
'busybox SCRIPT [ARGS]' or by usual (sym)link mechanism.
embed/nologin is provided as an example.
function old new delta
packed_scripts - 123 +123
unpack_scripts - 87 +87
ash_main 1103 1171 +68
run_applet_and_exit 78 128 +50
get_script_content - 32 +32
script_names - 10 +10
expmeta 663 659 -4
------------------------------------------------------------------------------
(add/remove: 4/0 grow/shrink: 2/1 up/down: 370/-4) Total: 366 bytes
Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/scripts/embedded_scripts b/scripts/embedded_scripts
new file mode 100755
index 0000000..986e851
--- /dev/null
+++ b/scripts/embedded_scripts
@@ -0,0 +1,66 @@
+#!/bin/sh
+
+target="$1"
+loc="$2"
+
+test "$target" || exit 1
+test "$SED" || SED=sed
+test "$DD" || DD=dd
+
+# Some people were bitten by their system lacking a (proper) od
+od -v -b </dev/null >/dev/null
+if test $? != 0; then
+ echo 'od tool is not installed or cannot accept "-v -b" options'
+ exit 1
+fi
+
+exec >"$target.$$"
+
+scripts=""
+if [ -d "$loc" ]
+then
+ scripts=$(cd $loc; ls * 2>/dev/null)
+fi
+
+n=$(echo $scripts | wc -w)
+
+if [ $n -ne 0 ]
+then
+ printf '#ifdef DEFINE_script_names\n'
+ printf 'const char script_names[] ALIGN1 = '
+ for i in $scripts
+ do
+ printf '"%s\\0"' $i
+ done
+ printf '"\\0";\n'
+ printf '#else\n'
+ printf 'extern const char script_names[] ALIGN1;\n'
+ printf '#endif\n'
+fi
+printf "#define NUM_SCRIPTS $n\n\n"
+
+if [ $n -ne 0 ]
+then
+ printf '#define UNPACKED_SCRIPTS_LENGTH '
+ for i in $scripts
+ do
+ cat $loc/$i
+ printf '\000'
+ done | wc -c
+
+ printf '#define PACKED_SCRIPTS \\\n'
+ for i in $scripts
+ do
+ cat $loc/$i
+ printf '\000'
+ done | bzip2 -1 | $DD bs=2 skip=1 2>/dev/null | od -v -b \
+ | grep -v '^ ' \
+ | $SED -e 's/^[^ ]*//' \
+ -e 's/ //g' \
+ -e '/^$/d' \
+ -e 's/\(...\)/0\1,/g' \
+ -e 's/$/ \\/'
+ printf '\n'
+fi
+
+mv -- "$target.$$" "$target"