1# ===========================================================================
2#     https://www.gnu.org/software/autoconf-archive/ax_python_devel.html
3# ===========================================================================
4#
5# SYNOPSIS
6#
7#   AX_PYTHON_DEVEL([version], [action-if-not-found])
8#
9# DESCRIPTION
10#
11#   Note: Defines as a precious variable "PYTHON_VERSION". Don't override it
12#   in your configure.ac.
13#
14#   Note: this is a slightly modified version of the original AX_PYTHON_DEVEL
15#   macro which accepts an additional [action-if-not-found] argument. This
16#   allow to detect if Python development is available without aborting the
17#   configure phase with an hard error in case it is not.
18#
19#   This macro checks for Python and tries to get the include path to
20#   'Python.h'. It provides the $(PYTHON_CPPFLAGS) and $(PYTHON_LIBS) output
21#   variables. It also exports $(PYTHON_EXTRA_LIBS) and
22#   $(PYTHON_EXTRA_LDFLAGS) for embedding Python in your code.
23#
24#   You can search for some particular version of Python by passing a
25#   parameter to this macro, for example ">= '2.3.1'", or "== '2.4'". Please
26#   note that you *have* to pass also an operator along with the version to
27#   match, and pay special attention to the single quotes surrounding the
28#   version number. Don't use "PYTHON_VERSION" for this: that environment
29#   variable is declared as precious and thus reserved for the end-user.
30#
31#   This macro should work for all versions of Python >= 2.1.0. As an end
32#   user, you can disable the check for the python version by setting the
33#   PYTHON_NOVERSIONCHECK environment variable to something else than the
34#   empty string.
35#
36#   If you need to use this macro for an older Python version, please
37#   contact the authors. We're always open for feedback.
38#
39# LICENSE
40#
41#   Copyright (c) 2009 Sebastian Huber <sebastian-huber@web.de>
42#   Copyright (c) 2009 Alan W. Irwin
43#   Copyright (c) 2009 Rafael Laboissiere <rafael@laboissiere.net>
44#   Copyright (c) 2009 Andrew Collier
45#   Copyright (c) 2009 Matteo Settenvini <matteo@member.fsf.org>
46#   Copyright (c) 2009 Horst Knorr <hk_classes@knoda.org>
47#   Copyright (c) 2013 Daniel Mullner <muellner@math.stanford.edu>
48#   Copyright (c) 2018 loli10K <ezomori.nozomu@gmail.com>
49#
50#   This program is free software: you can redistribute it and/or modify it
51#   under the terms of the GNU General Public License as published by the
52#   Free Software Foundation, either version 3 of the License, or (at your
53#   option) any later version.
54#
55#   This program is distributed in the hope that it will be useful, but
56#   WITHOUT ANY WARRANTY; without even the implied warranty of
57#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
58#   Public License for more details.
59#
60#   You should have received a copy of the GNU General Public License along
61#   with this program. If not, see <https://www.gnu.org/licenses/>.
62#
63#   As a special exception, the respective Autoconf Macro's copyright owner
64#   gives unlimited permission to copy, distribute and modify the configure
65#   scripts that are the output of Autoconf when processing the Macro. You
66#   need not follow the terms of the GNU General Public License when using
67#   or distributing such scripts, even though portions of the text of the
68#   Macro appear in them. The GNU General Public License (GPL) does govern
69#   all other use of the material that constitutes the Autoconf Macro.
70#
71#   This special exception to the GPL applies to versions of the Autoconf
72#   Macro released by the Autoconf Archive. When you make and distribute a
73#   modified version of the Autoconf Macro, you may extend this special
74#   exception to the GPL to apply to your modified version as well.
75
76#serial 21
77
78AU_ALIAS([AC_PYTHON_DEVEL], [AX_PYTHON_DEVEL])
79AC_DEFUN([AX_PYTHON_DEVEL],[
80	#
81	# Allow the use of a (user set) custom python version
82	#
83	AC_ARG_VAR([PYTHON_VERSION],[The installed Python
84		version to use, for example '2.3'. This string
85		will be appended to the Python interpreter
86		canonical name.])
87
88	AC_PATH_PROG([PYTHON],[python[$PYTHON_VERSION]])
89	if test -z "$PYTHON"; then
90		m4_ifvaln([$2],[$2],[
91			AC_MSG_ERROR([Cannot find python$PYTHON_VERSION in your system path])
92			PYTHON_VERSION=""
93		])
94	fi
95
96	#
97	# Check for a version of Python >= 2.1.0
98	#
99	AC_MSG_CHECKING([for a version of Python >= '2.1.0'])
100	ac_supports_python_ver=`$PYTHON -c "import sys; \
101		ver = sys.version.split ()[[0]]; \
102		print (ver >= '2.1.0')"`
103	if test "$ac_supports_python_ver" != "True"; then
104		if test -z "$PYTHON_NOVERSIONCHECK"; then
105			AC_MSG_RESULT([no])
106			AC_MSG_FAILURE([
107This version of the AC@&t@_PYTHON_DEVEL macro
108doesn't work properly with versions of Python before
1092.1.0. You may need to re-run configure, setting the
110variables PYTHON_CPPFLAGS, PYTHON_LIBS, PYTHON_SITE_PKG,
111PYTHON_EXTRA_LIBS and PYTHON_EXTRA_LDFLAGS by hand.
112Moreover, to disable this check, set PYTHON_NOVERSIONCHECK
113to something else than an empty string.
114])
115		else
116			AC_MSG_RESULT([skip at user request])
117		fi
118	else
119		AC_MSG_RESULT([yes])
120	fi
121
122	#
123	# If the macro parameter ``version'' is set, honour it.
124	# A Python shim class, VPy, is used to implement correct version comparisons via
125	# string expressions, since e.g. a naive textual ">= 2.7.3" won't work for
126	# Python 2.7.10 (the ".1" being evaluated as less than ".3").
127	#
128	if test -n "$1"; then
129		AC_MSG_CHECKING([for a version of Python $1])
130                cat << EOF > ax_python_devel_vpy.py
131class VPy:
132    def vtup(self, s):
133        return tuple(map(int, s.strip().replace("rc", ".").split(".")))
134    def __init__(self):
135        import sys
136        self.vpy = tuple(sys.version_info)
137    def __eq__(self, s):
138        return self.vpy == self.vtup(s)
139    def __ne__(self, s):
140        return self.vpy != self.vtup(s)
141    def __lt__(self, s):
142        return self.vpy < self.vtup(s)
143    def __gt__(self, s):
144        return self.vpy > self.vtup(s)
145    def __le__(self, s):
146        return self.vpy <= self.vtup(s)
147    def __ge__(self, s):
148        return self.vpy >= self.vtup(s)
149EOF
150		ac_supports_python_ver=`$PYTHON -c "import ax_python_devel_vpy; \
151                        ver = ax_python_devel_vpy.VPy(); \
152			print (ver $1)"`
153                rm -rf ax_python_devel_vpy*.py* __pycache__/ax_python_devel_vpy*.py*
154		if test "$ac_supports_python_ver" = "True"; then
155			AC_MSG_RESULT([yes])
156		else
157			AC_MSG_RESULT([no])
158			AC_MSG_ERROR([this package requires Python $1.
159If you have it installed, but it isn't the default Python
160interpreter in your system path, please pass the PYTHON_VERSION
161variable to configure. See ``configure --help'' for reference.
162])
163			PYTHON_VERSION=""
164		fi
165	fi
166
167	#
168	# Check for Python include path
169	#
170	#
171	AC_MSG_CHECKING([for Python include path])
172	if test -z "$PYTHON_CPPFLAGS"; then
173		python_path=`$PYTHON -c "import sysconfig; \
174			print (sysconfig.get_path('include'));"`
175		plat_python_path=`$PYTHON -c "import sysconfig; \
176			print (sysconfig.get_path('platinclude'));"`
177		if test -n "${python_path}"; then
178			if test "${plat_python_path}" != "${python_path}"; then
179				python_path="-I$python_path -I$plat_python_path"
180			else
181				python_path="-I$python_path"
182			fi
183		fi
184		PYTHON_CPPFLAGS=$python_path
185	fi
186	AC_MSG_RESULT([$PYTHON_CPPFLAGS])
187	AC_SUBST([PYTHON_CPPFLAGS])
188
189	#
190	# Check for Python library path
191	#
192	AC_MSG_CHECKING([for Python library path])
193	if test -z "$PYTHON_LIBS"; then
194		# (makes two attempts to ensure we've got a version number
195		# from the interpreter)
196		ac_python_version=`cat<<EOD | $PYTHON -
197
198# join all versioning strings, on some systems
199# major/minor numbers could be in different list elements
200from sysconfig import *
201e = get_config_var('VERSION')
202if e is not None:
203	print(e)
204EOD`
205
206		if test -z "$ac_python_version"; then
207			if test -n "$PYTHON_VERSION"; then
208				ac_python_version=$PYTHON_VERSION
209			else
210				ac_python_version=`$PYTHON -c "import sys; \
211					print ('.'.join(sys.version.split('.')[[:2]]))"`
212			fi
213		fi
214
215		# Make the versioning information available to the compiler
216		AC_DEFINE_UNQUOTED([HAVE_PYTHON], ["$ac_python_version"],
217                                   [If available, contains the Python version number currently in use.])
218
219		# First, the library directory:
220		ac_python_libdir=`cat<<EOD | $PYTHON -
221
222# There should be only one
223import sysconfig
224e = sysconfig.get_config_var('LIBDIR')
225if e is not None:
226	print (e)
227EOD`
228
229		# Now, for the library:
230		ac_python_library=`cat<<EOD | $PYTHON -
231
232import sysconfig
233c = sysconfig.get_config_vars()
234if 'LDVERSION' in c:
235	print ('python'+c[['LDVERSION']])
236else:
237	print ('python'+c[['VERSION']])
238EOD`
239
240		# This small piece shamelessly adapted from PostgreSQL python macro;
241		# credits goes to momjian, I think. I'd like to put the right name
242		# in the credits, if someone can point me in the right direction... ?
243		#
244		if test -n "$ac_python_libdir" -a -n "$ac_python_library"
245		then
246			# use the official shared library
247			ac_python_library=`echo "$ac_python_library" | sed "s/^lib//"`
248			PYTHON_LIBS="-L$ac_python_libdir -l$ac_python_library"
249		else
250			# old way: use libpython from python_configdir
251			ac_python_libdir=`$PYTHON -c \
252			  "import sysconfig; \
253			  import os; \
254			  print (os.path.join(sysconfig.get_path('platstdlib'), 'config'));"`
255			PYTHON_LIBS="-L$ac_python_libdir -lpython$ac_python_version"
256		fi
257
258		if test -z "PYTHON_LIBS"; then
259			m4_ifvaln([$2],[$2],[
260				AC_MSG_ERROR([
261  Cannot determine location of your Python DSO. Please check it was installed with
262  dynamic libraries enabled, or try setting PYTHON_LIBS by hand.
263				])
264			])
265		fi
266	fi
267	AC_MSG_RESULT([$PYTHON_LIBS])
268	AC_SUBST([PYTHON_LIBS])
269
270	#
271	# Check for site packages
272	#
273	AC_MSG_CHECKING([for Python site-packages path])
274	if test -z "$PYTHON_SITE_PKG"; then
275		PYTHON_SITE_PKG=`$PYTHON -c "import distutils.sysconfig; \
276			print (distutils.sysconfig.get_python_lib(0,0));" 2>/dev/null || \
277			$PYTHON -c "import sysconfig; \
278			print (sysconfig.get_path('purelib'));"`
279	fi
280	AC_MSG_RESULT([$PYTHON_SITE_PKG])
281	AC_SUBST([PYTHON_SITE_PKG])
282
283	#
284	# libraries which must be linked in when embedding
285	#
286	AC_MSG_CHECKING(python extra libraries)
287	if test -z "$PYTHON_EXTRA_LIBS"; then
288	   PYTHON_EXTRA_LIBS=`$PYTHON -c "import sysconfig; \
289                conf = sysconfig.get_config_var; \
290                print (conf('LIBS') + ' ' + conf('SYSLIBS'))"`
291	fi
292	AC_MSG_RESULT([$PYTHON_EXTRA_LIBS])
293	AC_SUBST(PYTHON_EXTRA_LIBS)
294
295	#
296	# linking flags needed when embedding
297	#
298	AC_MSG_CHECKING(python extra linking flags)
299	if test -z "$PYTHON_EXTRA_LDFLAGS"; then
300		PYTHON_EXTRA_LDFLAGS=`$PYTHON -c "import sysconfig; \
301			conf = sysconfig.get_config_var; \
302			print (conf('LINKFORSHARED'))"`
303	fi
304	AC_MSG_RESULT([$PYTHON_EXTRA_LDFLAGS])
305	AC_SUBST(PYTHON_EXTRA_LDFLAGS)
306
307	#
308	# final check to see if everything compiles alright
309	#
310	AC_MSG_CHECKING([consistency of all components of python development environment])
311	# save current global flags
312	ac_save_LIBS="$LIBS"
313	ac_save_LDFLAGS="$LDFLAGS"
314	ac_save_CPPFLAGS="$CPPFLAGS"
315	LIBS="$ac_save_LIBS $PYTHON_LIBS $PYTHON_EXTRA_LIBS $PYTHON_EXTRA_LIBS"
316	LDFLAGS="$ac_save_LDFLAGS $PYTHON_EXTRA_LDFLAGS"
317	CPPFLAGS="$ac_save_CPPFLAGS $PYTHON_CPPFLAGS"
318	AC_LANG_PUSH([C])
319	AC_LINK_IFELSE([
320		AC_LANG_PROGRAM([[#include <Python.h>]],
321				[[Py_Initialize();]])
322		],[pythonexists=yes],[pythonexists=no])
323	AC_LANG_POP([C])
324	# turn back to default flags
325	CPPFLAGS="$ac_save_CPPFLAGS"
326	LIBS="$ac_save_LIBS"
327	LDFLAGS="$ac_save_LDFLAGS"
328
329	AC_MSG_RESULT([$pythonexists])
330
331        if test ! "x$pythonexists" = "xyes"; then
332		m4_ifvaln([$2],[$2],[
333			AC_MSG_FAILURE([
334  Could not link test program to Python. Maybe the main Python library has been
335  installed in some non-standard library path. If so, pass it to configure,
336  via the LIBS environment variable.
337  Example: ./configure LIBS="-L/usr/non-standard-path/python/lib"
338  ============================================================================
339   ERROR!
340   You probably have to install the development version of the Python package
341   for your distribution.  The exact name of this package varies among them.
342  ============================================================================
343	   ])
344			PYTHON_VERSION=""
345		])
346	fi
347
348	#
349	# all done!
350	#
351])
352