Python config cleanup

Don't require Python at configure/build unless building pyzfs.
Move ZFS_AC_PYTHON_MODULE to always-pyzfs.m4 where it is used.
Make test syntax more consistent.

Sponsored by: iXsystems, Inc.
Reviewed-by: Neal Gompa <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Signed-off-by: Ryan Moeller <[email protected]>
Closes #8895 

1 files changed, 23 insertions, 64 deletions

diff --git a/config/always-python.m4 b/config/always-python.m4
index 7cfefd9eb..c1c07597e 100644
--- a/config/always-python.m4
+++ b/config/always-python.m4
@@ -1,48 +1,4 @@
 dnl #
-dnl # ZFS_AC_PYTHON_VERSION(version, [action-if-true], [action-if-false])
-dnl #
-dnl # Verify Python version
-dnl #
-AC_DEFUN([ZFS_AC_PYTHON_VERSION], [
-	ver_check=`$PYTHON -c "import sys; print (sys.version.split()[[0]] $1)"`
-	AS_IF([test "$ver_check" = "True"], [
-		m4_ifvaln([$2], [$2])
-	], [
-		m4_ifvaln([$3], [$3])
-	])
-])
-
-dnl #
-dnl # ZFS_AC_PYTHON_VERSION_IS_2
-dnl # ZFS_AC_PYTHON_VERSION_IS_3
-dnl #
-dnl # Tests if the $PYTHON_VERSION matches 2.x or 3.x.
-dnl #
-AC_DEFUN([ZFS_AC_PYTHON_VERSION_IS_2],
-	[test "${PYTHON_VERSION%%\.*}" = "2"])
-AC_DEFUN([ZFS_AC_PYTHON_VERSION_IS_3],
-	[test "${PYTHON_VERSION%%\.*}" = "3"])
-
-dnl #
-dnl # ZFS_AC_PYTHON_MODULE(module_name, [action-if-true], [action-if-false])
-dnl #
-dnl # Checks for Python module. Freely inspired by AX_PYTHON_MODULE
-dnl # https://www.gnu.org/software/autoconf-archive/ax_python_module.html
-dnl # Required by ZFS_AC_CONFIG_ALWAYS_PYZFS.
-dnl #
-AC_DEFUN([ZFS_AC_PYTHON_MODULE], [
-	PYTHON_NAME=`basename $PYTHON`
-	AC_MSG_CHECKING([for $PYTHON_NAME module: $1])
-	AS_IF([$PYTHON -c "import $1" 2>/dev/null], [
-		AC_MSG_RESULT(yes)
-		m4_ifvaln([$2], [$2])
-	], [
-		AC_MSG_RESULT(no)
-		m4_ifvaln([$3], [$3])
-	])
-])
-
-dnl #
 dnl # The majority of the python scripts are written to be compatible
 dnl # with Python 2.6 and Python 3.4.  Therefore, they may be installed
 dnl # and used with either interpreter.  This option is intended to
@@ -66,35 +22,38 @@ AC_DEFUN([ZFS_AC_CONFIG_ALWAYS_PYTHON], [
 		[AC_MSG_ERROR([Unknown --with-python value '$with_python'])]
 	)
 
-	AS_IF([test $PYTHON != :], [
-		AS_IF([$PYTHON --version >/dev/null 2>&1],
-			[AM_PATH_PYTHON([2.6], [], [:])],
-			[AC_MSG_ERROR([Cannot find $PYTHON in your system path])]
-		)
-	])
-	AM_CONDITIONAL([USING_PYTHON], [test "$PYTHON" != :])
-	AM_CONDITIONAL([USING_PYTHON_2], [ZFS_AC_PYTHON_VERSION_IS_2])
-	AM_CONDITIONAL([USING_PYTHON_3], [ZFS_AC_PYTHON_VERSION_IS_3])
-
 	dnl #
 	dnl # Minimum supported Python versions for utilities:
-	dnl # Python 2.6.x, or Python 3.4.x
+	dnl # Python 2.6 or Python 3.4
 	dnl #
-	AS_IF([ZFS_AC_PYTHON_VERSION_IS_2], [
-		ZFS_AC_PYTHON_VERSION([>= '2.6'], [ true ],
-			[AC_MSG_ERROR("Python >= 2.6.x is not available")])
+	AM_PATH_PYTHON([], [], [:])
+	AS_IF([test -z "$PYTHON_VERSION"], [
+		PYTHON_VERSION=$(basename $PYTHON | tr -cd 0-9.)
 	])
+	PYTHON_MINOR=${PYTHON_VERSION#*\.}
 
-	AS_IF([ZFS_AC_PYTHON_VERSION_IS_3], [
-		ZFS_AC_PYTHON_VERSION([>= '3.4'], [ true ],
-			[AC_MSG_ERROR("Python >= 3.4.x is not available")])
-	])
+	AS_CASE([$PYTHON_VERSION],
+		[2.*], [
+			AS_IF([test $PYTHON_MINOR -lt 6],
+				[AC_MSG_ERROR("Python >= 2.6 is required")])
+		],
+		[3.*], [
+			AS_IF([test $PYTHON_MINOR -lt 4],
+				[AC_MSG_ERROR("Python >= 3.4 is required")])
+		],
+		[:|2|3], [],
+		[PYTHON_VERSION=3]
+	)
+
+	AM_CONDITIONAL([USING_PYTHON], [test "$PYTHON" != :])
+	AM_CONDITIONAL([USING_PYTHON_2], [test "x${PYTHON_VERSION%%\.*}" = x2])
+	AM_CONDITIONAL([USING_PYTHON_3], [test "x${PYTHON_VERSION%%\.*}" = x3])
 
 	dnl #
 	dnl # Request that packages be built for a specific Python version.
 	dnl #
-	AS_IF([test $with_python != check], [
-		PYTHON_PKG_VERSION=`echo ${PYTHON} | tr -d 'a-zA-Z.'`
+	AS_IF([test "x$with_python" != xcheck], [
+		PYTHON_PKG_VERSION=$(echo $PYTHON_VERSION | tr -d .)
 		DEFINE_PYTHON_PKG_VERSION='--define "__use_python_pkg_version '${PYTHON_PKG_VERSION}'"'
 		DEFINE_PYTHON_VERSION='--define "__use_python '${PYTHON}'"'
 	], [