[PATCH] build.sh: Wrap host toolchain for rump builds

[Damien Zammit <damien%zamaudio.com@localhost>]

This enables host tool wrappers to be built with
'-V TOOLS_BUILDRUMP=yes tools' when built on non-NetBSD.
It enables rump and rumptest targets to work and libs
to be linked without building gcc on the other system without
breaking the targets on NetBSD.

TESTED on NetBSD:

	./build.sh -V TOOLS_BUILDRUMP=yes -V MKGROFF=no \
		-u -U -T ../tooldir tools rumptest

	./build.sh -V TOOLS_BUILDRUMP=yes -V MKGROFF=no \
		-u -U -T ../tooldir tools rump

TESTED on GNU/Hurd:

HOST_CC=gcc LDADD="-L/usr/lib/i386-gnu -L/usr/lib/gcc/i686-gnu/10" \
	_GCC_CRTENDS= _GCC_CRTBEGINS= _GCC_CRTI= _GCC_CRTN= \
	CFLAGS=-Wno-error=stack-protector \
	./build.sh -V TOOLS_BUILDRUMP=yes -V MKGROFF=no \
		-U -u -T ../tools -m i386 tools rumptest

HOST_CC=gcc LDADD="-L/usr/lib/i386-gnu -L/usr/lib/gcc/i686-gnu/10" \
	_GCC_CRTENDS= _GCC_CRTBEGINS= _GCC_CRTI= _GCC_CRTN= \
	CFLAGS=-Wno-error=stack-protector \
	./build.sh -V TOOLS_BUILDRUMP=yes -V MKGROFF=no \
		-U -u -T ../tools -m i386 tools rump
---
 build.sh       | 141 +++++++++++++++++++++++++++++++++++++++++++++----
 tools/Makefile |   4 +-
 2 files changed, 134 insertions(+), 11 deletions(-)

diff --git a/build.sh b/build.sh
index be70b3bfc4e5..deabe7c801d6 100755
--- a/build.sh
+++ b/build.sh
@@ -2195,6 +2195,121 @@ installworld()
 	statusmsg "Successful installworld to ${dir}"
 }
 
+printoneconfig ()
+{
+
+	[ -z "${2}" ] || printf "%-5s %-18s: %s\n" "${1}" "${2}" "${3}"
+}
+
+WRAPPERBODY='int
+main(int argc, const char *argv[])
+{
+	int i, j, k;
+
+	for (i = 1; i < argc; i++) {
+		for (j = 0; j < sizeof(mngl_from)/sizeof(mngl_from[0]); j++) {
+			if (strcmp(argv[i], mngl_from[j]) == 0) {
+				if (strlen(mngl_to[j]) == 0) {
+					for (k = i; k < argc; k++) {
+						argv[k] = argv[k+1];
+					}
+					argv[k] = '\0';
+					argc--;
+				} else {
+					argv[i] = mngl_to[j];
+				}
+				break;
+			}
+		}
+	}
+'
+
+maketoolwrapper ()
+{
+
+	musthave=$1
+	tool=$2
+
+	if [ "${tool}" = "CC" ]; then
+		lctool=gcc
+	elif [ "${tool}" = "CXX" ]; then
+		lctool=g++
+	else
+		lctool=$(echo ${tool} | tr '[A-Z]' '[a-z]')
+	fi
+	fptool=$(command -v ${lctool})
+	if [ ! -x ${fptool} ]; then
+		if ! ${musthave}; then
+			return
+		else
+			bomb "Internal error: mandatory tool ${tool} not found"
+		fi
+	fi
+
+	eval ttool=\'\${${tool}}\'
+	tname=`${runcmd} "${makewrapper}" -V "${ttool}"`
+	printoneconfig 'Tool' "${fptool}" "${tname}"
+
+	# Mangle wrapper arguments from what NetBSD does to what the
+	# toolchain we use supports.  In case we need mangling, do it
+	# with a C wrapper to preserve all quoting etc. (couldn't
+	# figure out how to get that right with a shell.
+	rm -f ${TOOLDIR}/wrapper.c
+	exec 3>&1 1>${TOOLDIR}/wrapper.c
+	printf '#include <inttypes.h>\n'
+	printf '#include <string.h>\n'
+	printf '#include <unistd.h>\n\n'
+	printf 'static const char *mngl_from[] = {\n'
+	(
+		IFS=:
+		for xf in ${CCWRAPPER_MANGLE}; do
+			IFS=' '
+			set -- ${xf}
+			printf '\t"%s",\n' ${1}
+		done
+	)
+	printf '};\nstatic const char *mngl_to[] ={\n'
+	(
+		IFS=:
+		for xf in ${CCWRAPPER_MANGLE}; do
+			IFS=' '
+			set -- ${xf}
+			printf '\t"%s",\n' ${2:-}
+		done
+	)
+	printf '};\n\n'
+	( IFS=' ' printf '%s' "${WRAPPERBODY}" )
+	printf '\targv[0] = "%s";\n' ${fptool}
+	printf '\texecvp(argv[0], (void *)(uintptr_t)argv);\n'
+	printf '\treturn 0;\n}\n'
+	exec 1>&3 3>&-
+
+	${HOST_CC} ${TOOLDIR}/wrapper.c -o ${tname} \
+	    || bomb "failed to build wrapper for ${tool}"
+	rm -f ${TOOLDIR}/wrapper.c
+
+	chmod 755 ${tname}
+}
+
+makerumptools ()
+{
+	[ -n "${TOOLDIR}" ] || bomb "TOOLDIR not set"
+
+	# Create external toolchain wrappers.
+	mkdir -p ${TOOLDIR}/bin || bomb "cannot create ${TOOLDIR}/bin"
+	for x in CC AR NM OBJCOPY; do
+		maketoolwrapper true $x
+	done
+	for x in AS LD OBJDUMP RANLIB READELF SIZE STRINGS STRIP CXX; do
+		maketoolwrapper false $x
+	done
+
+	# create a cpp wrapper, but run it via cc -E
+	tname=`${runcmd} "${makewrapper}" -V '${CPP}'`
+	printf '#!/bin/sh\n\nexec %s -E -x c "${@}"\n' ${CC} > ${tname}
+	chmod 755 ${tname}
+}
+
 # Run rump build&link tests.
 #
 # To make this feasible for running without having to install includes and
@@ -2260,14 +2375,14 @@ dorump()
 	# one little, two little, three little backslashes ...
 	md_quirks="$(echo ${md_quirks} | sed 's,\\,\\\\,g'";s/'//g" )"
 	${runcmd} cd "${TOP}" || bomb "cd to ${TOP} failed"
-	tool_ld=`${runcmd} "${makewrapper}" -V '${LD}'`
+	tool_cc=`${runcmd} "${makewrapper}" -V '${CC}'`
 
 	local oIFS="${IFS}"
 	IFS=","
 	for set in ${RUMP_LIBSETS} ; do
 		IFS="${oIFS}"
-		${runcmd} ${tool_ld} -nostdlib -L${DESTDIR}/usr/lib	\
-		    -static --whole-archive -lpthread -lc ${set} 2>&1 -o /tmp/rumptest.$$ | \
+		${runcmd} ${tool_cc} -nostdlib -L${DESTDIR}/usr/lib 	\
+		    -static --whole-archive -lpthread -lc -lgcc ${set} 2>&1 -o /tmp/rumptest.$$ | \
 		      awk -v quirks="${md_quirks}" '
 			/undefined reference/ &&
 			    !/more undefined references.*follow/{
@@ -2485,16 +2600,24 @@ main()
 			;;
 
 		rump)
-			make_in_dir . do-distrib-dirs
-			make_in_dir . includes
-			make_in_dir lib/csu dependall
-			make_in_dir lib/csu install
-			make_in_dir external/gpl3/gcc/lib/libgcc dependall
-			make_in_dir external/gpl3/gcc/lib/libgcc install
+			if [ "${uname_s}" != "NetBSD" ] || \
+				[ "${uname_m}" != "${MACHINE}" ]; then
+				makerumptools
+			else
+				make_in_dir . includes
+				make_in_dir lib/csu dependall
+				make_in_dir lib/csu install
+				make_in_dir external/gpl3/gcc/lib/libgcc dependall
+				make_in_dir external/gpl3/gcc/lib/libgcc install
+			fi
 			dorump "${op}"
 			;;
 
 		rumptest)
+			if [ "${uname_s}" != "NetBSD" ] || \
+				[ "${uname_m}" != "${MACHINE}" ]; then
+				makerumptools
+			fi
 			dorump "${op}"
 			;;
 
diff --git a/tools/Makefile b/tools/Makefile
index 177cd1846cda..1ab0135b59f3 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -100,10 +100,10 @@ SUBDIR=	host-mkdep compat binstall date \
 .if ${TOOLS_BUILDRUMP} == "no"
 SUBDIR+= cap_mkdb crunchgen ctags gencat hexdump \
 		${LINT_BITS} \
-		makewhatis mtree nbperf .WAIT uudecode
+		makewhatis nbperf .WAIT uudecode
 .endif
 
-SUBDIR+= cat rpcgen join lorder m4 mkdep tsort .WAIT yacc .WAIT awk .WAIT lex
+SUBDIR+= mtree cat rpcgen join lorder m4 mkdep tsort .WAIT yacc .WAIT awk .WAIT lex
 .if ${TOOLS_BUILDRUMP} == "no"
 SUBDIR+= xz-include .WAIT grep xz-lib pax .WAIT libprop
 
-- 
2.25.2