[python] add --with-pythondir

[Tom Tromey <tromey at redhat dot com>]

This patch adds a --with-pythondir configure option.

By default, we install the python code in $gdb_datadir/python.  This
directory is treated as relocatable, so if you move the whole $prefix
tree, it will keep working.

For a distro, however, we'd rather install gdb's python library in the
standard python library directory.  --with-pythondir enables this.  It
takes a directory argument.

Tom

2009-03-03  Tom Tromey  <tromey@redhat.com>

	* Makefile.in (pythondir): New variable.
	(install-python): Use it.
	(uninstall-python): Likewise.
	* python/python.c (_initialize_python): Set pythondir if
	--with-pythondir was given.  Use it during initialization.
	* configure, config.in: Rebuild.
	* configure.ac (--with-pythondir): New option.
	(PYTHONDIR): New define.
	(pythondir): New subst.

diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 3b43d29..81cdb83 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -175,6 +175,10 @@ TARGET_SYSTEM_ROOT_DEFINE = @TARGET_SYSTEM_ROOT_DEFINE@
 # Did the user give us a --with-gdb-datadir option?
 GDB_DATADIR_PATH = @GDB_DATADIR_PATH@
 
+# The argument to --with-pythondir.  If not given, this is
+# GDB_DATADIR_PATH/python.
+pythondir = @pythondir@
+
 # Helper code from gnulib.
 LIBGNU = gnulib/libgnu.a
 INCGNU = -I$(srcdir)/gnulib -Ignulib
@@ -1937,17 +1941,17 @@ PY_FILES = gdb/FrameIterator.py gdb/command/alias.py \
     gdb/__init__.py
 
 # Install the Python library.  Python library files go under
-# $(GDB_DATADIR_PATH)/python.
+# $(pythondir).
 install-python:
 	files='$(PY_FILES)'; for file in $$files; do \
 	  dir=`echo "$$file" | sed 's,/[^/]*$$,,'`; \
-	  $(SHELL) $(srcdir)/../mkinstalldirs $(DESTDIR)$(GDB_DATADIR_PATH)/python/$$dir; \
-	  $(INSTALL_DATA) $(srcdir)/python/lib/$$file $(DESTDIR)$(GDB_DATADIR_PATH)/python/$$file; \
+	  $(SHELL) $(srcdir)/../mkinstalldirs $(DESTDIR)$(pythondir)/$$dir; \
+	  $(INSTALL_DATA) $(srcdir)/python/lib/$$file $(DESTDIR)$(pythondir)/$$file; \
 	done
 
 # Brute force.
 uninstall-python:
-	rm -rf $(DESTDIR)/$(GDB_DATADIR_PATH)/python
+	rm -rf $(DESTDIR)/$(pythondir)
 
 #
 # Dependency tracking.  Most of this is conditional on GNU Make being
diff --git a/gdb/configure.ac b/gdb/configure.ac
index 95871d8..325d02f 100644
--- a/gdb/configure.ac
+++ b/gdb/configure.ac
@@ -1,6 +1,6 @@
 dnl Autoconf configure script for GDB, the GNU debugger.
 dnl Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
-dnl 2005, 2006, 2007, 2008
+dnl 2005, 2006, 2007, 2008, 2009
 dnl Free Software Foundation, Inc.
 dnl
 dnl This file is part of GDB.
@@ -148,6 +148,21 @@ esac
 GDB_DATADIR_PATH=${gdbdatadir}
 AC_SUBST(GDB_DATADIR_PATH)
 
+AC_ARG_WITH([pythondir],
+  [AS_HELP_STRING([--with-pythondir],
+                  [install Python data files in this path [DATADIR/gdb/python]])], [pythondir="${withval}"], [pythondir=no])
+
+# If the user passed in a path, define it.  Otherwise, compute it at
+# runtime based on the possibly-relocatable datadir.
+if test "$pythondir" = "no"; then
+  pythondir='$(GDB_DATADIR_PATH)/python'
+else
+  AC_DEFINE_UNQUOTED(PYTHONDIR, "$pythondir",
+      [Define to install path for Python sources])
+fi
+AC_SUBST(pythondir)
+
+
 AC_CONFIG_SUBDIRS(doc testsuite)
 
 # Check whether to support alternative target configurations
diff --git a/gdb/python/python.c b/gdb/python/python.c
index c338009..d751fd4 100644
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -1775,8 +1775,12 @@ Enables or disables auto-loading of Python code when an object is opened."),
   PyModule_AddStringConstant (gdb_module, "VERSION", (char*) version);
   PyModule_AddStringConstant (gdb_module, "HOST_CONFIG", (char*) host_name);
   PyModule_AddStringConstant (gdb_module, "TARGET_CONFIG", (char*) target_name);
+#ifdef PYTHONDIR
+  PyModule_AddStringConstant (gdb_module, "pythondir", PYTHONDIR);
+#else
   if (gdb_datadir)
     PyModule_AddStringConstant (gdb_module, "datadir", gdb_datadir);
+#endif
 
   gdbpy_initialize_values ();
   gdbpy_initialize_breakpoints ();
@@ -1827,11 +1831,12 @@ class GdbOutputFile:\n\
 sys.stderr = GdbOutputFile()\n\
 sys.stdout = GdbOutputFile()\n\
 if hasattr (gdb, 'datadir'):\n\
-  gdb.pythonlibdir = gdb.datadir + '/python'\n\
-  sys.path.insert(0, gdb.pythonlibdir)\n\
-  gdb.__path__ = [gdb.pythonlibdir + '/gdb']\n\
+  gdb.pythondir = gdb.datadir + '/python'\n\
+if hasattr (gdb, 'pythondir'):\n\
+  sys.path.insert(0, gdb.pythondir)\n\
+  gdb.__path__ = [gdb.pythondir + '/gdb']\n\
   from os.path import exists\n\
-  ipy = gdb.pythonlibdir + '/gdb/__init__.py'\n\
+  ipy = gdb.pythondir + '/gdb/__init__.py'\n\
   if exists (ipy):\n\
     execfile (ipy)\n\
 ");