Add support for writing unwinders in Python.

gdb/ChangeLog:

	* Makefile.in (SUBDIR_PYTHON_OBJS): Add py-unwind.o.
	(SUBDIR_PYTHON_SRCS): Add py-unwind.c.
	(py-unwind.o): New recipe.
	* NEWS: mention Python frame unwinding.
	* data-directory/Makefile.in (PYTHON_FILE_LIST): Add
	gdb/unwinder.py and gdb/command/unwinder.py
	* python/lib/gdb/__init__.py (packages): Add frame_unwinders
	list.
	(execute_unwinders): New function.
	* python/lib/gdb/command/unwinders.py: New file.
	* python/lib/gdb/unwinder.py: New file.
	* python/py-objfile.c (objfile_object): Add frame_unwinders field.
	(objfpy_dealloc): Decrement frame_unwinders reference count.
	(objfpy_initialize): Create frame_unwinders list.
	(objfpy_get_frame_unwinders): New function.
	(objfpy_set_frame_unwinders): Ditto.
	(objfile_getset): Add frame_unwinders attribute to Objfile.
	* python/py-progspace.c (pspace_object): Add frame_unwinders field.
	(pspy_dealloc): Decrement frame_unwinders reference count.
	(pspy_initialize): Create frame_unwinders list.
	(pspy_get_frame_unwinders): New function.
	(pspy_set_frame_unwinders): Ditto.
	(pspy_getset): Add frame_unwinders attribute to gdb.Progspace.
	* python/py-unwind.c: New file.
	* python/python-internal.h (pspy_get_name_unwinders): New prototype.
	(objpy_get_frame_unwinders): New prototype.
	(gdbpy_initialize_unwind): New prototype.
	* python/python.c (gdbpy_apply_type_printers): Call
	gdbpy_initialize_unwind.

gdb/doc/ChangeLog:

	* doc/python.texi (Writing a Frame Unwinder in Python): Add
	section.

gdb/testsuite/ChangeLog:

	* gdb.python/py-unwind-maint.c: New file.
	* gdb.python/py-unwind-maint.exp: New test.
	* gdb.python/py-unwind-maint.py: New file.
	* gdb.python/py-unwind.c: New file.
	* gdb.python/py-unwind.exp: New test.
	* gdb.python/py-unwind.py: New test.

1 files changed, 59 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.python/py-unwind-maint.py b/gdb/testsuite/gdb.python/py-unwind-maint.py
new file mode 100644
index 0000000..f8c6277
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-unwind-maint.py
@@ -0,0 +1,59 @@
+# Copyright (C) 2015 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# This file is part of the GDB testsuite.  It tests python unwinders.
+
+import re
+import gdb.types
+from gdb.unwinder import Unwinder, register_unwinder
+
+class TestGlobalUnwinder(Unwinder):
+    def __init__(self):
+        super(TestGlobalUnwinder, self).__init__("global_unwinder")
+
+    def __call__(self, unwinder_info):
+        print "%s called" % self.name
+        return None
+
+class TestProgspaceUnwinder(Unwinder):
+    def __init__(self, name):
+        super(TestProgspaceUnwinder, self).__init__("%s_ps_unwinder" % name)
+
+    def __call__(self, unwinder_info):
+        print "%s called" % self.name
+        return None
+
+class TestObjfileUnwinder(Unwinder):
+    def __init__(self, name):
+        super(TestObjfileUnwinder, self).__init__("%s_obj_unwinder" % name)
+
+    def __call__(self, unwinder_info):
+        print "%s called" % self.name
+        return None
+
+
+
+gdb.unwinder.register_unwinder(None, TestGlobalUnwinder())
+saw_runtime_error = False
+try:
+    gdb.unwinder.register_unwinder(None, TestGlobalUnwinder(), replace=False)
+except RuntimeError:
+    saw_runtime_error = True
+if not saw_runtime_error:
+    raise RuntimeError("Missing runtime error from register_unwinder.")
+gdb.unwinder.register_unwinder(None, TestGlobalUnwinder(), replace=True)
+gdb.unwinder.register_unwinder(gdb.current_progspace(),
+                               TestProgspaceUnwinder("py_unwind_maint"))
+print "Python script imported"