Merge from PG master upto d5cb3bab564e0927ffac7c8729eacf181a12dd40

This is the result of the "git merge remotes/PGSQL/master" upto the said commit
point. We have done some basic analysis, fixed compilation problems etc, but
bulk of the logical problems in conflict resolution etc will be handled by
subsequent commits.

1 files changed, 90 insertions, 18 deletions

diff --git a/config/python.m4 b/config/python.m4
index b95c8ed3b3..953d709305 100644
--- a/config/python.m4
+++ b/config/python.m4
@@ -18,7 +18,8 @@ fi
 
 # _PGAC_CHECK_PYTHON_DIRS
 # -----------------------
-# Determine the name of various directories of a given Python installation.
+# Determine the name of various directories of a given Python installation,
+# as well as the Python version.
 AC_DEFUN([_PGAC_CHECK_PYTHON_DIRS],
 [AC_REQUIRE([PGAC_PATH_PYTHON])
 AC_MSG_CHECKING([for Python distutils module])
@@ -31,10 +32,16 @@ else
 fi
 AC_MSG_CHECKING([Python configuration directory])
 python_majorversion=`${PYTHON} -c "import sys; print(sys.version[[0]])"`
+python_minorversion=`${PYTHON} -c "import sys; print(sys.version[[2]])"`
 python_version=`${PYTHON} -c "import sys; print(sys.version[[:3]])"`
 python_configdir=`${PYTHON} -c "import distutils.sysconfig; print(' '.join(filter(None,distutils.sysconfig.get_config_vars('LIBPL'))))"`
 AC_MSG_RESULT([$python_configdir])
 
+# Reject unsupported Python versions as soon as practical.
+if test "$python_majorversion" -lt 3 -a "$python_minorversion" -lt 4; then
+  AC_MSG_ERROR([Python version $python_version is too old (version 2.4 or later is required)])
+fi
+
 AC_MSG_CHECKING([Python include directories])
 python_includespec=`${PYTHON} -c "
 import distutils.sysconfig
@@ -58,36 +65,101 @@ AC_SUBST(python_includespec)[]dnl
 # PGAC_CHECK_PYTHON_EMBED_SETUP
 # -----------------------------
 #
-# Note: selecting libpython from python_configdir works in all Python
-# releases, but it generally finds a non-shared library, which means
-# that we are binding the python interpreter right into libplpython.so.
-# In Python 2.3 and up there should be a shared library available in
-# the main library location.
+# Set python_libdir to the path of the directory containing the Python shared
+# library.  Set python_libspec to the -L/-l linker switches needed to link it.
+# Set python_additional_libs to contain any additional linker switches needed
+# for subsidiary libraries.
+#
+# In modern, well-configured Python installations, LIBDIR gives the correct
+# directory name and LDLIBRARY is the file name of the shlib.  But in older
+# installations LDLIBRARY is frequently a useless path fragment, and it's also
+# possible that the shlib is in a standard library directory such as /usr/lib
+# so that LIBDIR is irrelevant.  Also, some packagers put the .so symlink for
+# the shlib in ${python_configdir} even though Python itself never does.
+# We must also check that what we found is a shared library not a plain
+# library, which we do by checking its extension.  (We used to rely on
+# Py_ENABLE_SHARED, but that only tells us that a shlib exists, not that
+# we found it.)
 AC_DEFUN([PGAC_CHECK_PYTHON_EMBED_SETUP],
 [AC_REQUIRE([_PGAC_CHECK_PYTHON_DIRS])
 AC_MSG_CHECKING([how to link an embedded Python application])
 
 python_libdir=`${PYTHON} -c "import distutils.sysconfig; print(' '.join(filter(None,distutils.sysconfig.get_config_vars('LIBDIR'))))"`
 python_ldlibrary=`${PYTHON} -c "import distutils.sysconfig; print(' '.join(filter(None,distutils.sysconfig.get_config_vars('LDLIBRARY'))))"`
-python_so=`${PYTHON} -c "import distutils.sysconfig; print(' '.join(filter(None,distutils.sysconfig.get_config_vars('SO'))))"`
-ldlibrary=`echo "${python_ldlibrary}" | sed "s/${python_so}$//"`
-python_enable_shared=`${PYTHON} -c "import distutils.sysconfig; print(distutils.sysconfig.get_config_vars().get('Py_ENABLE_SHARED',0))"`
 
-if test x"${python_libdir}" != x"" -a x"${python_ldlibrary}" != x"" -a x"${python_ldlibrary}" != x"${ldlibrary}"
+# If LDLIBRARY exists and has a shlib extension, use it verbatim.
+ldlibrary=`echo "${python_ldlibrary}" | sed -e 's/\.so$//' -e 's/\.dll$//' -e 's/\.dylib$//' -e 's/\.sl$//'`
+if test -e "${python_libdir}/${python_ldlibrary}" -a x"${python_ldlibrary}" != x"${ldlibrary}"
 then
-	# New way: use the official shared library
 	ldlibrary=`echo "${ldlibrary}" | sed "s/^lib//"`
-	python_libspec="-L${python_libdir} -l${ldlibrary}"
+	found_shlib=1
 else
-	# Old way: use libpython from python_configdir
-	python_libdir="${python_configdir}"
-	# LDVERSION was introduced in Python 3.2.
+	# Otherwise, guess the base name of the shlib.
+	# LDVERSION was added in Python 3.2, before that use VERSION,
+	# or failing that, $python_version from _PGAC_CHECK_PYTHON_DIRS.
 	python_ldversion=`${PYTHON} -c "import distutils.sysconfig; print(' '.join(filter(None,distutils.sysconfig.get_config_vars('LDVERSION'))))"`
-	if test x"${python_ldversion}" = x""; then
-		python_ldversion=$python_version
+	if test x"${python_ldversion}" != x""; then
+		ldlibrary="python${python_ldversion}"
+	else
+		python_version_var=`${PYTHON} -c "import distutils.sysconfig; print(' '.join(filter(None,distutils.sysconfig.get_config_vars('VERSION'))))"`
+		if test x"${python_version_var}" != x""; then
+			ldlibrary="python${python_version_var}"
+		else
+			ldlibrary="python${python_version}"
+		fi
 	fi
-	python_libspec="-L${python_libdir} -lpython${python_ldversion}"
+	# Search for a likely-looking file.
+	found_shlib=0
+	for d in "${python_libdir}" "${python_configdir}" /usr/lib64 /usr/lib
+	do
+		# We don't know the platform DLSUFFIX here, so check 'em all.
+		for e in .so .dll .dylib .sl; do
+			if test -e "$d/lib${ldlibrary}$e"; then
+				python_libdir="$d"
+				found_shlib=1
+				break 2
+			fi
+		done
+	done
+	# Some platforms (OpenBSD) require us to accept a bare versioned shlib
+	# (".so.n.n") as well. However, check this only after failing to find
+	# ".so" anywhere, because yet other platforms (Debian) put the .so
+	# symlink in a different directory from the underlying versioned shlib.
+	if test "$found_shlib" != 1; then
+		for d in "${python_libdir}" "${python_configdir}" /usr/lib64 /usr/lib
+		do
+			for f in "$d/lib${ldlibrary}.so."* ; do
+				if test -e "$f"; then
+					python_libdir="$d"
+					found_shlib=1
+					break 2
+				fi
+			done
+		done
+	fi
+	# As usual, Windows has its own ideas.  Possible default library
+	# locations include c:/Windows/System32 and (for Cygwin) /usr/bin,
+	# and the "lib" prefix might not be there.
+	if test "$found_shlib" != 1 -a \( "$PORTNAME" = win32 -o "$PORTNAME" = cygwin \); then
+		for d in "${python_libdir}" "${python_configdir}" c:/Windows/System32 /usr/bin
+		do
+			for f in "$d/lib${ldlibrary}.dll" "$d/${ldlibrary}.dll" ; do
+				if test -e "$f"; then
+					python_libdir="$d"
+					found_shlib=1
+					break 2
+				fi
+			done
+		done
+	fi
+fi
+if test "$found_shlib" != 1; then
+	AC_MSG_ERROR([could not find shared library for Python
+You might have to rebuild your Python installation.  Refer to the
+documentation for details.  Use --without-python to disable building
+PL/Python.])
 fi
+python_libspec="-L${python_libdir} -l${ldlibrary}"
 
 python_additional_libs=`${PYTHON} -c "import distutils.sysconfig; print(' '.join(filter(None,distutils.sysconfig.get_config_vars('LIBS','LIBC','LIBM','BASEMODLIBS'))))"`