#! /bin/sh
set -e

# Convert templates into Makefile and config.c, based on the module
# definitions found in the file Setup.
#
# Usage: makesetup [-s dir] [-c file] [-m file] [Setup] ... [-n [Setup] ...]
#
# Options:
# -s directory: alternative source directory (default .)
# -l directory: library source directory (default derived from $0)
# -c file:      alternative config.c template (default $libdir/config.c.in)
# -c -:         don't write config.c
# -m file:      alternative Makefile template (default ./Makefile.pre)
# -m -:         don't write Makefile
#
# Remaining arguments are one or more Setup files (default ./Setup).
# Setup files after a -n option are used for their variables, modules
# and libraries but not for their .o files.
#
# See Setup for a description of the format of the Setup file.
#
# The following edits are made:
#
# Copying config.c.in to config.c:
# - insert an identifying comment at the start
# - for each <module> mentioned in Setup before *noconfig*:
#   + insert 'extern PyObject* PyInit_<module>(void);' before MARKER 1
#   + insert '{"<module>", PyInit_<module>},' before MARKER 2
#
# Copying Makefile.pre to Makefile:
# - insert an identifying comment at the start
# - replace _MODBUILT_NAMES_ by the list of *static* and *shared* modules
#   from Setup
# - replace _MODBSHARED_NAMES_ by the list of *shared* modules from Setup
# - replace _MODDISABLED_NAMES_ by the list of *disabled* modules from Setup
# - replace _MODOBJS_ by the list of objects from Setup (except for
#   Setup files after a -n option)
# - replace _MODLIBS_ by the list of libraries from Setup
# - for each object file mentioned in Setup, append a rule
#   '<file>.o: <file>.c; <build commands>' to the end of the Makefile
# - for each module mentioned in Setup, append a rule
#   which creates a shared library version to the end of the Makefile
# - for each variable definition found in Setup, insert the definition
#   before the comment 'Definitions added by makesetup'

# Loop over command line options
usage='
usage: makesetup [-s srcdir] [-l libdir] [-c config.c.in] [-m Makefile.pre]
                 [Setup] ... [-n [Setup] ...]'
srcdir='.'
libdir=''
config=''
makepre=''
noobjects=''
doconfig=yes
while :
do
	case $1 in
	-s)	shift; srcdir=$1; shift;;
	-l)	shift; libdir=$1; shift;;
	-c)	shift; config=$1; shift;;
	-m)	shift; makepre=$1; shift;;
	--)	shift; break;;
	-n)	noobjects=yes;;
	-*)	echo "$usage" 1>&2; exit 2;;
	*)	break;;
	esac
done

# Set default libdir and config if not set by command line
# (Not all systems have dirname)
case $libdir in
'')	case $0 in
	*/*)	libdir=`echo $0 | sed 's,/[^/]*$,,'`;;
	*)	libdir=.;;
	esac;;
esac
case $config in
'')	config=$libdir/config.c.in;;
esac
case $makepre in
'')	makepre=Makefile.pre;;
esac

# Newline for sed i and a commands
NL='\
'

# Setup to link with extra libraries when making shared extensions.
# Currently, only Cygwin needs this baggage.
case `uname -s` in
CYGWIN*) if test $libdir = .
	 then
	 	ExtraLibDir=.
	 else
	 	ExtraLibDir='$(LIBPL)'
	 fi
	 ExtraLibs="-L$ExtraLibDir -lpython\$(LDVERSION)";;
esac

# Main loop
for i in ${*-Setup}
do
	case $i in
	-n)	echo '*noobjects*';;
	*)	echo '*doconfig*'; cat "$i";;
	esac
done |
sed -e 's/[ 	]*#.*//' -e '/^[ 	]*$/d' |
(
	rulesf="@rules.$$"
	trap 'rm -f $rulesf' 0 1 2 3
	echo "
# Rules appended by makesetup
" >$rulesf
	DEFS=
	BUILT=
	BUILT_SHARED=
	DISABLED=
	CONFIGURED=
	MODS=
	SHAREDMODS=
	OBJS=
	LIBS=
	LOCALLIBS=
	BASELIBS=
	while read line
	do
		# to handle backslashes for sh's that don't automatically
		# continue a read when the last char is a backslash
		while echo $line | grep '\\$' > /dev/null
		do
			read extraline
			line=`echo $line| sed s/.$//`$extraline
		done

		# Output DEFS in reverse order so first definition overrides
		case $line in
		*=*)	DEFS="$line$NL$DEFS"; continue;;
		'include '*)	DEFS="$line$NL$DEFS"; continue;;
		'*noobjects*')
			case $noobjects in
			yes)	;;
			*)	LOCALLIBS=$LIBS; LIBS=;;
			esac
			noobjects=yes;
			continue;;
		'*doconfig*')	doconfig=yes; continue;;
		'*static*')	doconfig=yes; continue;;
		'*noconfig*')	doconfig=no; continue;;
		'*shared*')	doconfig=no; continue;;
		'*disabled*')	doconfig=disabled; continue;;
		esac
		srcs=
		cpps=
		libs=
		mods=
		mods_upper=
		skip=
		for arg in $line
		do
			case $skip in
			libs)	libs="$libs $arg"; skip=; continue;;
			cpps)	cpps="$cpps $arg"; skip=; continue;;
			srcs)	srcs="$srcs $arg"; skip=; continue;;
			esac
			case $arg in
			-framework)	libs="$libs $arg"; skip=libs;
				        # OSX/OSXS/Darwin framework link cmd
					;;
			-[IDUCfF]*)	cpps="$cpps $arg";;
			-Xcompiler)	skip=cpps;;
			-Xlinker)	libs="$libs $arg"; skip=libs;;
			-rpath)		libs="$libs $arg"; skip=libs;;
			--rpath)	libs="$libs $arg"; skip=libs;;
			-[A-Zl]*)	libs="$libs $arg";;
			*.a)		libs="$libs $arg";;
			*.so)		libs="$libs $arg";;
			*.sl)		libs="$libs $arg";;
			/*.o)		libs="$libs $arg";;
			*.def)		libs="$libs $arg";;
			*.o)		srcs="$srcs `basename $arg .o`.c";;
			*.[cC])		srcs="$srcs $arg";;
			*.m)		srcs="$srcs $arg";; # Objective-C src
			*.cc)		srcs="$srcs $arg";;
			*.c++)		srcs="$srcs $arg";;
			*.cxx)		srcs="$srcs $arg";;
			*.cpp)		srcs="$srcs $arg";;
			\$\(*_CFLAGS\))		cpps="$cpps $arg";;
			\$\(*_INCLUDES\))	cpps="$cpps $arg";;
			\$\(*_LIBS\))		libs="$libs $arg";;
			\$\(*_LDFLAGS\))	libs="$libs $arg";;
			\$\(*_RPATH\))		libs="$libs $arg";;
			\$*)		libs="$libs $arg"
					cpps="$cpps $arg";;
			*.*)		echo 1>&2 "bad word $arg in $line"
					exit 1;;
			-u)		skip=libs; libs="$libs -u";;
			[a-zA-Z_]*)
					mods="$mods $arg"
					mods_upper=$(echo $mods | tr '[a-z]' '[A-Z]');;
			*)		echo 1>&2 "bad word $arg in $line"
					exit 1;;
			esac
		done
		if test -z "$cpps" -a -z "$libs"; then
			cpps="\$(MODULE_${mods_upper}_CFLAGS)"
			libs="\$(MODULE_${mods_upper}_LDFLAGS)"
		fi
		for mod in $mods
		do
			case $CONFIGURED in
			*,${mod},*)
				# Detected multiple rules for a module, first rule wins. This
				# allows users to disable modules in Setup.local.
				echo 1>&2 "maksetup: '$mod' was handled by previous rule."
				continue 2;;
			esac
			CONFIGURED="$CONFIGURED,${mod},"
		done
		case $doconfig in
		yes)
			LIBS="$LIBS $libs"
			MODS="$MODS $mods"
			BUILT="$BUILT $mods"
			;;
		no)
			BUILT="$BUILT $mods"
			;;
		disabled)
			DISABLED="$DISABLED $mods"
			continue
			;;
		esac
		case $noobjects in
		yes)	continue;;
		esac
		objs=''
		for src in $srcs
		do
			case $src in
			*.c)   obj=`basename $src .c`.o; cc='$(CC)';;
			*.cc)  obj=`basename $src .cc`.o; cc='$(CXX)';;
			*.c++) obj=`basename $src .c++`.o; cc='$(CXX)';;
			*.C)   obj=`basename $src .C`.o; cc='$(CXX)';;
			*.cxx) obj=`basename $src .cxx`.o; cc='$(CXX)';;
			*.cpp) obj=`basename $src .cpp`.o; cc='$(CXX)';;
			*.m)   obj=`basename $src .m`.o; cc='$(CC)';; # Obj-C
			*)     continue;;
			esac
			case $src in
			*/*) obj="$srcdir/`dirname $src`/$obj";;
			*)   obj="$srcdir/$obj";;
			esac
			objs="$objs $obj"
			case $src in
			glmodule.c) ;;
			/*) ;;
			\$*) ;;
			*) src='$(srcdir)/'"$srcdir/$src";;
			esac
			# custom flags first, PY_STDMODULE_CFLAGS may contain -I with system libmpdec
			case $doconfig in
			no)	cc="$cc $cpps \$(PY_STDMODULE_CFLAGS) \$(CCSHARED)";;
			*)
				cc="$cc $cpps \$(PY_BUILTIN_MODULE_CFLAGS)";;
			esac
			# force rebuild when header file or module build flavor (static/shared) is changed
			rule="$obj: $src \$(MODULE_${mods_upper}_DEPS) \$(PYTHON_HEADERS) Modules/config.c; $cc -c $src -o $obj"
			echo "$rule" >>$rulesf
		done
		case $doconfig in
		yes)	OBJS="$OBJS $objs";;
		esac
		for mod in $mods
		do
			file="$srcdir/$mod\$(EXT_SUFFIX)"
			case $doconfig in
			no)
				SHAREDMODS="$SHAREDMODS $file"
				BUILT_SHARED="$BUILT_SHARED $mod"
				;;
			esac
			rule="$file: $objs"
			rule="$rule; \$(BLDSHARED) $objs $libs $ExtraLibs -o $file"
			echo "$rule" >>$rulesf
		done
	done

	case $SHAREDMODS in
	'')	;;
	*)	DEFS="SHAREDMODS=$SHAREDMODS$NL$DEFS";;
	esac

	case $noobjects in
	yes)	BASELIBS=$LIBS;;
	*)	LOCALLIBS=$LIBS;;
	esac
	LIBS='$(LOCALMODLIBS) $(BASEMODLIBS)'
	DEFS="BASEMODLIBS=$BASELIBS$NL$DEFS"
	DEFS="LOCALMODLIBS=$LOCALLIBS$NL$DEFS"

	EXTDECLS=
	INITBITS=
	for mod in $MODS
	do
		EXTDECLS="${EXTDECLS}extern PyObject* PyInit_$mod(void);$NL"
		INITBITS="${INITBITS}    {\"$mod\", PyInit_$mod},$NL"
	done


	case $config in
	-)  ;;
	*)  sed -e "
		1i$NL/* Generated automatically from $config by makesetup. */
		/MARKER 1/i$NL$EXTDECLS

		/MARKER 2/i$NL$INITBITS

		" $config >config.c
	    ;;
	esac

	case $makepre in
	-)	;;
	*)
		# macOS' sed has issues with 'a' command. Use 'r' command with an
		# external replacement file instead.
		sedf="@sed.in.$$"
		sedr="@sed.replace.$$"
		trap 'rm -f $sedf $sedr' 0 1 2 3
		echo "$NL$NL$DEFS" | sed 's/\\$//' > $sedr
		echo "1i\\" >$sedf
		str="# Generated automatically from $makepre by makesetup."
		echo "$str" >>$sedf
		echo "s%_MODBUILT_NAMES_%$BUILT%" >>$sedf
		echo "s%_MODSHARED_NAMES_%$BUILT_SHARED%" >>$sedf
		echo "s%_MODDISABLED_NAMES_%$DISABLED%" >>$sedf
		echo "s%_MODOBJS_%$OBJS%" >>$sedf
		echo "s%_MODLIBS_%$LIBS%" >>$sedf
		echo "/Definitions added by makesetup/r $sedr" >>$sedf
		sed -f $sedf $makepre >Makefile
		cat $rulesf >>Makefile
		rm -f $sedf $sedr
	    ;;
	esac

	rm -f $rulesf
)