build system: add support for non-portable host headers.

1 files changed, 82 insertions, 0 deletions

diff --git a/sysinfo/host/host.sh b/sysinfo/host/host.sh
new file mode 100755
index 0000000..50186e7
--- /dev/null
+++ b/sysinfo/host/host.sh
@@ -0,0 +1,82 @@
+#!/bin/sh
+
+error_msg()
+{
+	echo $@ >&2
+}
+
+host_test()
+{
+	mb_hdrdir=$(pwd)/build
+	mkdir -p $mb_hdrdir || exit 2
+
+	if [ x"$mb_compiler" = x ]; then
+                echo "config error: compiler not set."
+		exit 2
+	fi
+
+	"$mb_compiler" -dM -E - < /dev/null > /dev/null && return 0
+
+	error_msg "config error: invalid compiler."
+	exit 2
+}
+
+host_endian_h()
+{
+	mb_header='endian.h'
+	rm -f "$mb_hdrdir"/$mb_header
+
+	# portable
+	"$mb_compiler" $mb_cflags \
+		--include=$mb_header -E - < /dev/null > /dev/null 2>/dev/null \
+		&& return 0
+
+	# non-portable
+	mb_hosthdr=
+
+	[ -z $mb_hosthdr ] && "$mb_compiler" $mb_cflags \
+		--include='sys/'$mb_header -E - < /dev/null > /dev/null 2>/dev/null \
+		&& mb_hosthdr='sys/'$mb_header
+
+	[ -z $mb_hosthdr ] && "$mb_compiler" $mb_cflags \
+		--include='machine/'$mb_header -E - < /dev/null > /dev/null 2>/dev/null \
+		&& mb_hosthdr='machine/'$mb_header
+
+	if [ x"$mb_hosthdr" = x ]; then
+		error_msg "config error: could not find an alternate <$mb_header>."
+		exit 2
+	fi
+
+	printf "#include <%s>\\n" $mb_hosthdr > "$mb_hdrdir"/$mb_header || exit 2
+}
+
+
+# one: args
+for arg ; do
+	case "$arg" in
+		--help)	usage
+			;;
+		--compiler=*)
+			mb_compiler=${arg#*=}
+			;;
+		--cflags=*)
+			mb_cflags=${arg#*=}
+			;;
+		*)
+			error_msg ${arg#}: "unsupported config argument."
+			exit 2
+			;;
+	esac
+done
+
+
+# two: test
+host_test
+
+
+# three: headers
+host_endian_h
+
+
+# all done
+exit 0