#!/bin/bash

# Grab default values for $CFLAGS and such.

source ./configure

echo "Extract configuration information from toys/*.c files..."
scripts/genconfig.sh

echo "Generate headers from toys/*.c..."

# Create a list of all the applets toybox can provide.  Note that the first
# entry is out of order on purpose (the toybox multiplexer applet must be the
# first element of the array).  The rest must be sorted in alphabetical order
# for fast binary search.

function newtoys()
{
  for i in toys/*.c
  do
    sed -n -e '1,/^config [A-Z]/s/^USE_/&/p' $i || exit 1
  done
}
echo "NEWTOY(toybox, NULL, TOYFLAG_STAYROOT)" > generated/newtoys.h
newtoys | sed 's/\(.*TOY(\)\([^,]*\),\(.*\)/\2 \1\2,\3/' | sort -k 1,1 \
	| sed 's/[^ ]* //'  >> generated/newtoys.h

# Extract global structure definitions and flag definitions from toys/*.c

function getglobals()
{
  for i in toys/*.c
  do
    NAME="$(echo $i | sed 's@toys/\(.*\)\.c@\1@')"

    echo -e "// $i\n"
    sed -n -e '/^DEFINE_GLOBALS(/,/^)/b got;b;:got' \
        -e 's/^DEFINE_GLOBALS(/struct '"$NAME"'_data {/' \
        -e 's/^)/};/' -e 'p' $i

    # And get flag definitions
    FLAGS="$(sed -n \
                 -e "s/.*TOY($NAME"',[ \t]*"\([^"]*\)"[ \t]*,.*)/\1/' \
                 -e 't keep;d;:keep' \
                 -e 's/[><=][0-9][0-9]*//g' \
                 -e 's/+.//g' \
                 -e 's/([^)]*)//g' \
                 -e 's/[-?^:&#|@*]//g' \
                 -e 'p' \
                 generated/newtoys.h)"
    X=0
    while [ $X -lt ${#FLAGS} ]
    do
      echo -ne "#define OPTFLAG_${NAME}_${FLAGS:$X:1}\t"
      X=$(($X+1))
      echo "(1<<$((${#FLAGS}-$X)))"
    done
  done
}

GLOBSTRUCT="$(getglobals)"
(
  echo "$GLOBSTRUCT"
  echo
  echo "extern union global_union {"
  echo "$GLOBSTRUCT" | sed -n 's/struct \(.*\)_data {/	struct \1_data \1;/p'
  echo "} this;"
) > generated/globals.h

# Only recreate generated/help.h if python is installed
if [ ! -z "$(which python)" ] && [ ! -z "$(grep 'CONFIG_HELP=y' .config)" ]
then
  echo "Extract help text from Config.in."
  scripts/config2help.py Config.in > generated/help.h || exit 1
fi

echo "Make generated/config.h from .config."

# This long and roundabout sed invocation is to make old versions of sed happy.
# New ones have '\n' so can replace one line with two without all the branches
# and tedious mucking about with hold space.

sed -n \
  -e 's/^# CONFIG_\(.*\) is not set.*/\1/' \
  -e 't notset' \
  -e 's/^CONFIG_\(.*\)=y.*/\1/' \
  -e 't isset' \
  -e 's/^CONFIG_\([^=]*\)=\(.*\)/#define CFG_\1 \2/p' \
  -e 'd' \
  -e ':notset' \
  -e 'h' \
  -e 's/.*/#define CFG_& 0/p' \
  -e 'g' \
  -e 's/.*/#define USE_&(...)/p' \
  -e 'd' \
  -e ':isset' \
  -e 'h' \
  -e 's/.*/#define CFG_& 1/p' \
  -e 'g' \
  -e 's/.*/#define USE_&(...) __VA_ARGS__/p' \
  .config > generated/config.h || exit 1

# Extract a list of toys/*.c files to compile from the data in ".config" with
# sed, sort, and tr:

# 1) Grab the XXX part of all CONFIG_XXX entries, removing everything after the
# second underline
# 2) Sort the list, keeping only one of each entry.
# 3) Convert to lower case.
# 4) Remove toybox itself from the list (as that indicates global symbols).
# 5) Add "toys/" prefix and ".c" suffix.

TOYFILES=$(cat .config | sed -nre 's/^CONFIG_(.*)=y/\1/;t skip;b;:skip;s/_.*//;p' | sort -u | tr A-Z a-z | grep -v '^toybox$' | sed 's@\(.*\)@toys/\1.c@' )

echo "Library probe..."

OPTLIBS="$(for i in util crypt m; do echo "int main(int argc, char *argv[]) {return 0;}" | ${CROSS_COMPILE}${CC} -xc - -o /dev/null -Wl,--as-needed -l$i > /dev/null 2>/dev/null && echo -l$i; done)"

echo "Compile toybox..."

do_loudly()
{
  [ ! -z "$V" ] && echo "$@"
  "$@"
}

do_loudly ${CROSS_COMPILE}${CC} $CFLAGS -I . -o toybox_unstripped $OPTIMIZE \
  main.c lib/*.c $TOYFILES -Wl,--as-needed $OPTLIBS  || exit 1
do_loudly ${CROSS_COMPILE}${STRIP} toybox_unstripped -o toybox || exit 1
# gcc 4.4's strip command is buggy, and doesn't set the executable bit on
# its output the way SUSv4 suggests it do so.
do_loudly chmod +x toybox || exit 1