config/python.m4

   1 #
   2 # Autoconf macros for configuring the build of Python extension modules
   3 #
   4 # config/python.m4
   5 #
   6
   7 # PGAC_PATH_PYTHON
   8 # ----------------
   9 # Look for Python and set the output variable 'PYTHON' if found,
  10 # fail otherwise.
  11 #
  12 # Since we are supporting only Python 3.x, prefer python3 to plain python.  If
  13 # the latter exists at all, it very possibly points to python2.
  14
  15 # As the Python 3 transition happens and PEP 394 isn't updated, we
  16 # need to cater to systems that don't have unversioned "python" by
  17 # default.  Some systems ship with "python3" by default and perhaps
  18 # have "python" in an optional package.  Some systems only have
  19 # "python2" and "python3", in which case it's reasonable to prefer the
  20 # newer version.
  21 AC_DEFUN([PGAC_PATH_PYTHON],
  22 [PGAC_PATH_PROGS(PYTHON, [python3 python])
  23 AC_ARG_VAR(PYTHON, [Python program])dnl
  24 if test x"$PYTHON" = x""; then
  25   AC_MSG_ERROR([Python not found])
  26 fi
  27 ])
  28
  29
  30 # _PGAC_CHECK_PYTHON_DIRS
  31 # -----------------------
  32 # Determine the name of various directories of a given Python installation,
  33 # as well as the Python version.
  34 AC_DEFUN([_PGAC_CHECK_PYTHON_DIRS],
  35 [AC_REQUIRE([PGAC_PATH_PYTHON])
  36 python_fullversion=`${PYTHON} -c "import sys; print(sys.version)" | sed q`
  37 AC_MSG_NOTICE([using python $python_fullversion])
  38 # python_fullversion is typically n.n.n plus some trailing junk
  39 python_majorversion=`echo "$python_fullversion" | sed '[s/^\([0-9]*\).*/\1/]'`
  40 python_minorversion=`echo "$python_fullversion" | sed '[s/^[0-9]*\.\([0-9]*\).*/\1/]'`
  41 python_version=`echo "$python_fullversion" | sed '[s/^\([0-9]*\.[0-9]*\).*/\1/]'`
  42 # Reject unsupported Python versions as soon as practical.
  43 if test "$python_majorversion" -lt 3; then
  44   AC_MSG_ERROR([Python version $python_version is too old (version 3 or later is required)])
  45 fi
  46
  47 AC_MSG_CHECKING([for Python sysconfig module])
  48 if "${PYTHON}" -c 'import sysconfig' 2>&AS_MESSAGE_LOG_FD
  49 then
  50     AC_MSG_RESULT(yes)
  51 else
  52     AC_MSG_RESULT(no)
  53     AC_MSG_ERROR([sysconfig module not found])
  54 fi
  55
  56 AC_MSG_CHECKING([Python configuration directory])
  57 python_configdir=`${PYTHON} -c "import sysconfig; print(' '.join(filter(None,sysconfig.get_config_vars('LIBPL'))))"`
  58 AC_MSG_RESULT([$python_configdir])
  59
  60 AC_MSG_CHECKING([Python include directory])
  61 python_includespec=`${PYTHON} -c "import sysconfig; print('-I' + sysconfig.get_config_var('INCLUDEPY'))"`
  62 if test "$PORTNAME" = win32 ; then
  63     python_includespec=`echo $python_includespec | sed 's,[[\]],/,g'`
  64 fi
  65 AC_MSG_RESULT([$python_includespec])
  66
  67 AC_SUBST(python_majorversion)[]dnl
  68 AC_SUBST(python_version)[]dnl
  69 AC_SUBST(python_includespec)[]dnl
  70 ])# _PGAC_CHECK_PYTHON_DIRS
  71
  72
  73 # PGAC_CHECK_PYTHON_EMBED_SETUP
  74 # -----------------------------
  75 #
  76 # Set python_libdir to the path of the directory containing the Python shared
  77 # library.  Set python_libspec to the -L/-l linker switches needed to link it.
  78 # Set python_additional_libs to contain any additional linker switches needed
  79 # for subsidiary libraries.
  80 #
  81 # In modern, well-configured Python installations, LIBDIR gives the correct
  82 # directory name and LDLIBRARY is the file name of the shlib.  But in older
  83 # installations LDLIBRARY is frequently a useless path fragment, and it's also
  84 # possible that the shlib is in a standard library directory such as /usr/lib
  85 # so that LIBDIR is irrelevant.  Also, some packagers put the .so symlink for
  86 # the shlib in ${python_configdir} even though Python itself never does.
  87 # We must also check that what we found is a shared library not a plain
  88 # library, which we do by checking its extension.  (We used to rely on
  89 # Py_ENABLE_SHARED, but that only tells us that a shlib exists, not that
  90 # we found it.)
  91 AC_DEFUN([PGAC_CHECK_PYTHON_EMBED_SETUP],
  92 [AC_REQUIRE([_PGAC_CHECK_PYTHON_DIRS])
  93 AC_MSG_CHECKING([how to link an embedded Python application])
  94
  95 python_libdir=`${PYTHON} -c "import sysconfig; print(' '.join(filter(None,sysconfig.get_config_vars('LIBDIR'))))"`
  96 python_ldlibrary=`${PYTHON} -c "import sysconfig; print(' '.join(filter(None,sysconfig.get_config_vars('LDLIBRARY'))))"`
  97
  98 # If LDLIBRARY exists and has a shlib extension, use it verbatim.
  99 ldlibrary=`echo "${python_ldlibrary}" | sed -e 's/\.so$//' -e 's/\.dll$//' -e 's/\.dylib$//' -e 's/\.sl$//'`
 100 if test -e "${python_libdir}/${python_ldlibrary}" -a x"${python_ldlibrary}" != x"${ldlibrary}"
 101 then
 102         ldlibrary=`echo "${ldlibrary}" | sed "s/^lib//"`
 103         found_shlib=1
 104 else
 105         # Otherwise, guess the base name of the shlib.
 106         # LDVERSION was added in Python 3.2, before that use VERSION,
 107         # or failing that, $python_version from _PGAC_CHECK_PYTHON_DIRS.
 108         python_ldversion=`${PYTHON} -c "import sysconfig; print(' '.join(filter(None,sysconfig.get_config_vars('LDVERSION'))))"`
 109         if test x"${python_ldversion}" != x""; then
 110                 ldlibrary="python${python_ldversion}"
 111         else
 112                 python_version_var=`${PYTHON} -c "import sysconfig; print(' '.join(filter(None,sysconfig.get_config_vars('VERSION'))))"`
 113                 if test x"${python_version_var}" != x""; then
 114                         ldlibrary="python${python_version_var}"
 115                 else
 116                         ldlibrary="python${python_version}"
 117                 fi
 118         fi
 119         # Search for a likely-looking file.
 120         found_shlib=0
 121         for d in "${python_libdir}" "${python_configdir}" /usr/lib64 /usr/lib
 122         do
 123                 # Note: DLSUFFIX is for loadable modules, not shared
 124                 # libraries, so cannot be used here portably.  Just
 125                 # check all known possibilities.
 126                 for e in .so .dll .dylib .sl; do
 127                         if test -e "$d/lib${ldlibrary}$e"; then
 128                                 python_libdir="$d"
 129                                 found_shlib=1
 130                                 break 2
 131                         fi
 132                 done
 133         done
 134         # Some platforms (OpenBSD) require us to accept a bare versioned shlib
 135         # (".so.n.n") as well. However, check this only after failing to find
 136         # ".so" anywhere, because yet other platforms (Debian) put the .so
 137         # symlink in a different directory from the underlying versioned shlib.
 138         if test "$found_shlib" != 1; then
 139                 for d in "${python_libdir}" "${python_configdir}" /usr/lib64 /usr/lib
 140                 do
 141                         for f in "$d/lib${ldlibrary}.so."* ; do
 142                                 if test -e "$f"; then
 143                                         python_libdir="$d"
 144                                         found_shlib=1
 145                                         break 2
 146                                 fi
 147                         done
 148                 done
 149         fi
 150         # As usual, Windows has its own ideas.  Possible default library
 151         # locations include c:/Windows/System32 and (for Cygwin) /usr/bin,
 152         # and the "lib" prefix might not be there.
 153         if test "$found_shlib" != 1 -a \( "$PORTNAME" = win32 -o "$PORTNAME" = cygwin \); then
 154                 for d in "${python_libdir}" "${python_configdir}" c:/Windows/System32 /usr/bin
 155                 do
 156                         for f in "$d/lib${ldlibrary}.dll" "$d/${ldlibrary}.dll" ; do
 157                                 if test -e "$f"; then
 158                                         python_libdir="$d"
 159                                         found_shlib=1
 160                                         break 2
 161                                 fi
 162                         done
 163                 done
 164         fi
 165 fi
 166 if test "$found_shlib" != 1; then
 167         AC_MSG_ERROR([could not find shared library for Python
 168 You might have to rebuild your Python installation.  Refer to the
 169 documentation for details.  Use --without-python to disable building
 170 PL/Python.])
 171 fi
 172 python_libspec="-L${python_libdir} -l${ldlibrary}"
 173
 174 python_additional_libs=`${PYTHON} -c "import sysconfig; print(' '.join(filter(None,sysconfig.get_config_vars('LIBS','LIBC','LIBM','BASEMODLIBS'))))"`
 175
 176 AC_MSG_RESULT([${python_libspec} ${python_additional_libs}])
 177
 178 AC_SUBST(python_libdir)[]dnl
 179 AC_SUBST(python_libspec)[]dnl
 180 AC_SUBST(python_additional_libs)[]dnl
 181
 182 ])# PGAC_CHECK_PYTHON_EMBED_SETUP