#!/bin/sh

GREP=${GREP:-grep}
MD5=${MD5:-md5sum}

cat << END
/*
 * buildopts.h
 * Automatically generated
 */

END

if ${GREP} "AST_DEVMODE" makeopts | ${GREP} -q "yes"
then
	echo "#define AST_DEVMODE 1"
	# AST_DEVMODE is no longer an API/ABI affecting option so it no longer
	# gets added to BUILDOPTS.
fi

ADD_CFLAGS_TO_BUILDOPTS=false
MENUSELECT_CFLAGS=$(${GREP} -e "^MENUSELECT_CFLAGS" menuselect.makeopts)
echo "$MENUSELECT_CFLAGS" | grep -q -e "ADD_CFLAGS_TO_BUILDOPTS_H" && ADD_CFLAGS_TO_BUILDOPTS=true

# Clean up MENUSELECT_CFLAGS by removing the "MENUSELECT_CFLAGS="
# at the front, the "ADD_CFLAGS_TO_BUILDOPTS_H" flag, and any "-D"
# entries.
MENUSELECT_CFLAGS=$( echo "$MENUSELECT_CFLAGS" | \
	sed -r -e "s/(MENUSELECT_CFLAGS=|ADD_CFLAGS_TO_BUILDOPTS_H|-D)//g")

# This is a list of flags that don't affect the ABI.
# "ADD_CFLAGS_TO_BUILDOPTS_H" is NOT set, we'll filter these
# out of the buildopts.h file.
#
# These used to always be filtered out but if they're not in
# buildopts.h, many IDEs will show them as undefined and mark
# any code blocks enabled by them as disabled.
#
# The original reasoning for removing them was that trivial
# changes to the buildopts.h file will cause ccache to
# invalidate any source files that use it and increase the
# compile time.  It's not such a huge deal these days but
# to preserve backwards behavior the default is still to
# remove them.
# 
# The ABI-breaking flags are always included in buildopts.h.

# This variable is used by sed so it needs to be a valid
# regex which will be surrounded by parens.]
FILTER_OUT="\
AO2_DEBUG|BETTER_BACKTRACES|BUILD_NATIVE|\
COMPILE_DOUBLE|DEBUG_CHAOS|DEBUG_SCHEDULER|\
DETECT_DEADLOCKS|DONT_OPTIMIZE|DUMP_SCHEDULER|\
LOTS_OF_SPANS|MALLOC_DEBUG|RADIO_RELAX|\
REBUILD_PARSERS|REF_DEBUG|USE_HOARD_ALLOCATOR"

# Create buildopts.h

INCLUDE_CFLAGS="$MENUSELECT_CFLAGS"
# Do the filter-out if needed.
if ! $ADD_CFLAGS_TO_BUILDOPTS ; then
	INCLUDE_CFLAGS=$( echo "$MENUSELECT_CFLAGS" | \
		sed -r -e "s/(${FILTER_OUT})//g")
fi

# Output the defines.
for x in ${INCLUDE_CFLAGS}; do
	echo "#define ${x} 1"
done

# We NEVER include the non-ABI-breaking flags in the
# BUILDOPTS or use them to calculate the checksum so
# we always filter out any that may exist.
# After the filter-out, we also need to convert the
# possibly-multi-spaced MENUSELECT_CFLAGS to a nice
# comma-separated list.
# I.E.
#  Remove leading spaces.
#  Convert consecutive interior spaces to a single space.
#  Remove trailing spaces.
#  Convert the now-single-spaces in the interior to ", ".
BUILDOPTS=$( echo "$MENUSELECT_CFLAGS" | \
	sed -r -e "s/(${FILTER_OUT}|LOW_MEMORY)//g" -e "s/^\s+//g;s/\s+/ /g;s/\s+$//g;s/\s/, /g" )

# Calculate the checksum on only the ABI-breaking flags.
BUILDSUM=$(echo "${BUILDOPTS}" | ${MD5} | cut -c1-32)

echo "#define AST_BUILDOPT_SUM \"${BUILDSUM}\""
echo "#define AST_BUILDOPTS \"${BUILDOPTS}\""

# However, it'd be nice to see the non-ABI-breaking flags
# when you do a "core show settings" so we create a separate
# define for them.
BUILDOPTS_ALL=$( echo "$MENUSELECT_CFLAGS" | \
	sed -r -e "s/^\s+//g;s/\s+/ /g;s/\s+$//g;s/\s/, /g" )
echo "#define AST_BUILDOPTS_ALL \"${BUILDOPTS_ALL}\""