:
# remove extra #include's

if ! pgdefine
then	echo "pgdefine must be in your PATH" 1>&2
	exit 1
fi

trap "rm -f /tmp/$$.c /tmp/$$.o /tmp/$$ /tmp/$$a /tmp/$$b" 0 1 2 3 15

if [ "$1" = "-v" ]
then	VERBOSE="Y"
else	VERBOSE=""
fi

verbose_output() {
	if [ "$VERBOSE" ]
	then	cat /tmp/$$
		cat /tmp/$$b
		nl /tmp/$$.c
	fi
}

process_includes_in_file() {
	# loop through all includes mentioned in the file
	cat "$FILE" | 
	grep "^#include\>" |
	grep -v '/\* *pgrminclude  *ignore *\*/' |
	sed 's/^#include[ 	]*[<"]\([^>"]*\).*$/\1/g' |
	grep -v 'parser/kwlist\.h' |
	grep -v '\.c$' |
	while read INCLUDE
	do	if [ "$VERBOSE" ]
		then	echo "checking $FILE $INCLUDE"
		fi
		compile_file
	done
}

compile_file() {
	[ "$INCLUDE" -a -s /usr/include/"$INCLUDE" ] && continue
	[ "$INCLUDE" = "postgres.h" ] && continue
	[ "$INCLUDE" = "postgres_fe.h" ] && continue
	[ "$INCLUDE" = "pg_config.h" ] && continue
	[ "$INCLUDE" = "c.h" ] && continue

	# preserve configure-specific includes
	# these includes are surrounded by #ifdef's
	grep -B1 '^#include[ 	][ 	]*[<"]'"$INCLUDE"'[>"]' "$FILE" |
	     egrep -q '^#if|^#else|^#elif' && continue
	grep -A1 '^#include[ 	][ 	]*[<"]'"$INCLUDE"'[>"]' "$FILE" |
	     egrep -q '^#else|^#elif|^#endif' && continue

        # Remove all #if and #ifdef blocks because the blocks
	# might contain code that is not compiled on this platform.
	cat "$FILE" |
	grep -v "^#if" |
	grep -v "^#else" |
	grep -v "^#elif" |
	grep -v "^#endif" |
	# with #if blocks gone, now undef #defines to avoid redefine 
	# warning and failure
	sed 's/#define[ 	][ 	]*\([A-Za-z0-9_]*\).*$/#undef \1\n&/' >/tmp/$$a

	# set up initial file contents
	grep -v '^#include[ 	][ 	]*[<"]'"$INCLUDE"'[>"]' \
		/tmp/$$a >/tmp/$$b

	if [ "$IS_INCLUDE" = "Y" ]
	then	echo "#include \"postgres.h\"" >/tmp/$$.c
	else	>/tmp/$$.c
	fi

	echo "#include \"/tmp/$$b\"" >>/tmp/$$.c
	# supress fcinfo errors
	echo "#undef PG_GETARG_DATUM" >>/tmp/$$.c
	echo "#define PG_GETARG_DATUM(n)" >>/tmp/$$.c
	echo "void include_test(void);" >>/tmp/$$.c
	echo "void include_test() {" >>/tmp/$$.c
	if [ "$IS_INCLUDE" = "Y" ]
	then	pgdefine "$FILE" >>/tmp/$$.c
	fi
	echo "}" >>/tmp/$$.c

	# Use -O1 to get warnings only generated by optimization,
	# but -O2 is too slow.
	cc -fsyntax-only -Werror -Wall -Wmissing-prototypes \
		-Wmissing-declarations -I/pg/include -I/pg/backend \
		-I/pg/interfaces/libpq -I`dirname $FILE` $CFLAGS -O1 -c /tmp/$$.c \
		-o /tmp/$$.o >/tmp/$$ 2>&1
	if [ "$?" -eq 0 ]
	then	[ "$INCLUDE" -o "$VERBOSE" ] && echo "$FILE $INCLUDE"
		grep -v '^#include[ 	][ 	]*[<"]'"$INCLUDE"'[>"]' \
			"$FILE" >/tmp/$$b
		mv /tmp/$$b "$FILE"
		return 0
	else	return 1
	fi
}

# Process include files first because they can affect the compilation 
# of *.c files.
(find . \( -name .git -a -prune \) -o -type f -name '*.h' -print;
 find . \( -name .git -a -prune \) -o -type f -name '*.c' -print ) |
grep -v '/postgres.h$' |
grep -v '/postgres_fe.h$' |
grep -v '/pg_config.h$' |
grep -v '\./c.h$' |
while read FILE
do
	if [ `expr $FILE : '.*\.h$'` -ne 0 ]
	then	IS_INCLUDE="Y"
	else	IS_INCLUDE="N"
	fi

	# Can we compile the file with all existing includes?
	INCLUDE=""
	compile_file
	# If the file can't be compiled on its own, there is no sense
	# trying to remove the include files.
	if [ "$?" -ne 0 ]
	then	echo "cannot compile $FILE with existing includes"
		verbose_output
	else	process_includes_in_file
	fi
done
