From FEDORA_PATCHES Mon Sep 17 00:00:00 2001
From: Andrew Burgess <aburgess@redhat.com>
Date: Sun, 15 Oct 2023 22:48:42 +0100
Subject: gdb-add-missing-debug-info-python-hook.patch
;; Backport upstream commit 8f6c452b5a4.
gdb: implement missing debug handler hook for Python
This commit builds on the previous commit, and implements the
extension_language_ops::handle_missing_debuginfo function for Python.
This hook will give user supplied Python code a chance to help find
missing debug information.
The implementation of the new hook is pretty minimal within GDB's C++
code; most of the work is out-sourced to a Python implementation which
is modelled heavily on how GDB's Python frame unwinders are
implemented.
The following new commands are added as commands implemented in
Python, this is similar to how the Python unwinder commands are
implemented:
info missing-debug-handlers
enable missing-debug-handler LOCUS HANDLER
disable missing-debug-handler LOCUS HANDLER
To make use of this extension hook a user will create missing debug
information handler objects, and registers these handlers with GDB.
When GDB encounters an objfile that is missing debug information, each
handler is called in turn until one is able to help. Here is a
minimal handler that does nothing useful:
import gdb
import gdb.missing_debug
class MyFirstHandler(gdb.missing_debug.MissingDebugHandler):
def __init__(self):
super().__init__("my_first_handler")
def __call__(self, objfile):
# This handler does nothing useful.
return None
gdb.missing_debug.register_handler(None, MyFirstHandler())
Returning None from the __call__ method tells GDB that this handler
was unable to find the missing debug information, and GDB should ask
any other registered handlers.
By extending the __call__ method it is possible for the Python
extension to locate the debug information for objfile and return a
value that tells GDB how to use the information that has been located.
Possible return values from a handler:
- None: This means the handler couldn't help. GDB will call other
registered handlers to see if they can help instead.
- False: The handler has done all it can, but the debug information
for the objfile still couldn't be found. GDB will not call
any other handlers, and will continue without the debug
information for objfile.
- True: The handler has installed the debug information into a
location where GDB would normally expect to find it. GDB
should look again for the debug information.
- A string: The handler can return a filename, which is the file
containing the missing debug information. GDB will load
this file.
When a handler returns True, GDB will look again for the debug
information, but only using the standard built-in build-id and
.gnu_debuglink based lookup strategies. It is not possible for an
extension to trigger another debuginfod lookup; the assumption is that
the debuginfod server is remote, and out of the control of extensions
running within GDB.
Handlers can be registered globally, or per program space. GDB checks
the handlers for the current program space first, and then all of the
global handles. The first handler that returns a value that is not
None, has "handled" the objfile, at which point GDB continues.
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>
diff --git a/gdb/data-directory/Makefile.in b/gdb/data-directory/Makefile.in
--- a/gdb/data-directory/Makefile.in
+++ b/gdb/data-directory/Makefile.in
@@ -73,6 +73,7 @@ PYTHON_FILE_LIST = \
gdb/FrameDecorator.py \
gdb/FrameIterator.py \
gdb/frames.py \
+ gdb/missing_debug.py \
gdb/printing.py \
gdb/prompt.py \
gdb/styling.py \
@@ -82,6 +83,7 @@ PYTHON_FILE_LIST = \
gdb/command/__init__.py \
gdb/command/explore.py \
gdb/command/frame_filters.py \
+ gdb/command/missing_debug.py \
gdb/command/pretty_printers.py \
gdb/command/prompt.py \
gdb/command/type_printers.py \
diff --git a/gdb/doc/python.texi b/gdb/doc/python.texi
--- a/gdb/doc/python.texi
+++ b/gdb/doc/python.texi
@@ -229,6 +229,7 @@ optional arguments while skipping others. Example:
* Connections In Python:: Python representation of connections.
* TUI Windows In Python:: Implementing new TUI windows.
* Disassembly In Python:: Instruction Disassembly In Python
+* Missing Debug Info In Python:: Handle missing debug info from Python.
@end menu
@node Basic Python
@@ -5191,6 +5192,12 @@ The @code{frame_filters} attribute is a dictionary of frame filter
objects. @xref{Frame Filter API}, for more information.
@end defvar
+@defvar Progspace.missing_debug_handlers
+The @code{missing_debug_handlers} attribute is a list of the missing
+debug handler objects for this program space. @xref{Missing Debug
+Info In Python}, for more information.
+@end defvar
+
A program space has the following methods:
@defun Progspace.block_for_pc (pc)
@@ -7770,6 +7777,139 @@ class NibbleSwapDisassembler(gdb.disassembler.Disassembler):
gdb.disassembler.register_disassembler(NibbleSwapDisassembler())
@end smallexample
+@node Missing Debug Info In Python
+@subsubsection Missing Debug Info In Python
+@cindex python, handle missing debug information
+
+When @value{GDBN} encounters a new objfile (@pxref{Objfiles In
+Python}), e.g.@: the primary executable, or any shared libraries used
+by the inferior, @value{GDBN} will attempt to load the corresponding
+debug information for that objfile. The debug information might be
+found within the objfile itself, or within a separate objfile which
+@value{GDBN} will automatically locate and load.
+
+Sometimes though, @value{GDBN} might not find any debug information
+for an objfile, in this case the debugging experience will be
+restricted.
+
+If @value{GDBN} fails to locate any debug information for a particular
+objfile, there is an opportunity for a Python extension to step in. A
+Python extension can potentially locate the missing debug information
+using some platform- or project-specific steps, and inform
+@value{GDBN} of its location. Or a Python extension might provide
+some platform- or project-specific advice to the user about how to
+obtain the missing debug information.
+
+A missing debug information Python extension consists of a handler
+object which has the @code{name} and @code{enabled} attributes, and
+implements the @code{__call__} method. When @value{GDBN} encounters
+an objfile for which it is unable to find any debug information, it
+invokes the @code{__call__} method. Full details of how handlers are
+written can be found below.
+
+@subheading The @code{gdb.missing_debug} Module
+
+@value{GDBN} comes with a @code{gdb.missing_debug} module which
+contains the following class and global function:
+
+@deftp{class} gdb.missing_debug.MissingDebugHandler
+
+@code{MissingDebugHandler} is a base class from which user-created
+handlers can derive, though it is not required that handlers derive
+from this class, so long as any user created handler has the
+@code{name} and @code{enabled} attributes, and implements the
+@code{__call__} method.
+
+@defun MissingDebugHandler.__init__ (name)
+The @var{name} is a string used to reference this missing debug
+handler within some @value{GDBN} commands. Valid names consist of the
+characters @code{[-_a-zA-Z0-9]}, creating a handler with an invalid
+name raises a @code{ValueError} exception.
+@end defun
+
+@defun MissingDebugHandler.__call__ (objfile)
+Sub-classes must override the @code{__call__} method. The
+@var{objfile} argument will be a @code{gdb.Objfile}, this is the
+objfile for which @value{GDBN} was unable to find any debug
+information.
+
+The return value from the @code{__call__} method indicates what
+@value{GDBN} should do next. The possible return values are:
+
+@itemize @bullet
+@item @code{None}
+
+This indicates that this handler could not help with @var{objfile},
+@value{GDBN} should call any other registered handlers.
+
+@item @code{True}
+
+This indicates that this handler has installed the debug information
+into a location where @value{GDBN} would normally expect to find it
+when looking for separate debug information files (@pxref{Separate
+Debug Files}). @value{GDBN} will repeat the normal lookup process,
+which should now find the separate debug file.
+
+If @value{GDBN} still doesn't find the separate debug information file
+after this second attempt, then the Python missing debug information
+handlers are not invoked a second time, this prevents a badly behaved
+handler causing @value{GDBN} to get stuck in a loop. @value{GDBN}
+will continue without any debug information for @var{objfile}.
+
+@item @code{False}
+
+This indicates that this handler has done everything that it intends
+to do with @var{objfile}, but no separate debug information can be
+found. @value{GDBN} will not call any other registered handlers for
+@var{objfile}. @value{GDBN} will continue without debugging
+information for @var{objfile}.
+
+@item A string
+
+The returned string should contain a filename. @value{GDBN} will not
+call any further registered handlers, and will instead load the debug
+information from the file identified by the returned filename.
+@end itemize
+
+Invoking the @code{__call__} method from this base class will raise a
+@code{NotImplementedError} exception.
+@end defun
+
+@defvar MissingDebugHandler.name
+A read-only attribute which is a string, the name of this handler
+passed to the @code{__init__} method.
+@end defvar
+
+@defvar MissingDebugHandler.enabled
+A modifiable attribute containing a boolean; when @code{True}, the
+handler is enabled, and will be used by @value{GDBN}. When
+@code{False}, the handler has been disabled, and will not be used.
+@end defvar
+@end deftp
+
+@defun gdb.missing_debug.register_handler (locus, handler, replace=@code{False})
+Register a new missing debug handler with @value{GDBN}.
+
+@var{handler} is an instance of a sub-class of
+@code{MissingDebugHandler}, or at least an instance of an object that
+has the same attributes and methods as @code{MissingDebugHandler}.
+
+@var{locus} specifies to which handler list to prepend @var{handler}.
+It can be either a @code{gdb.Progspace} (@pxref{Progspaces In Python})
+or @code{None}, in which case the handler is registered globally. The
+newly registered @var{handler} will be called before any other handler
+from the same locus. Two handlers in the same locus cannot have the
+same name, an attempt to add a handler with an already existing name
+raises an exception unless @var{replace} is @code{True}, in which case
+the old handler is deleted and the new handler is prepended to the
+selected handler list.
+
+@value{GDBN} first calls the handlers for the current program space,
+and then the globally registered handlers. As soon as a handler
+returns a value other than @code{None}, no further handlers are called
+for this objfile.
+@end defun
+
@node Python Auto-loading
@subsection Python Auto-loading
@cindex Python auto-loading
diff --git a/gdb/python/lib/gdb/__init__.py b/gdb/python/lib/gdb/__init__.py
--- a/gdb/python/lib/gdb/__init__.py
+++ b/gdb/python/lib/gdb/__init__.py
@@ -84,6 +84,8 @@ xmethods = []
frame_filters = {}
# Initial frame unwinders.
frame_unwinders = []
+# Initial missing debug handlers.
+missing_debug_handlers = []
def _execute_unwinders(pending_frame):
@@ -291,3 +293,42 @@ class Thread(threading.Thread):
# threads.
with blocked_signals():
super().start()
+
+
+def _handle_missing_debuginfo(objfile):
+ """Internal function called from GDB to execute missing debug
+ handlers.
+
+ Run each of the currently registered, and enabled missing debug
+ handler objects for the current program space and then from the
+ global list. Stop after the first handler that returns a result
+ other than None.
+
+ Arguments:
+ objfile: A gdb.Objfile for which GDB could not find any debug
+ information.
+
+ Returns:
+ None: No debug information could be found for objfile.
+ False: A handler has done all it can with objfile, but no
+ debug information could be found.
+ True: Debug information might have been installed by a
+ handler, GDB should check again.
+ A string: This is the filename of a file containing the
+ required debug information.
+ """
+ pspace = objfile.progspace
+
+ for handler in pspace.missing_debug_handlers:
+ if handler.enabled:
+ result = handler(objfile)
+ if result is not None:
+ return result
+
+ for handler in missing_debug_handlers:
+ if handler.enabled:
+ result = handler(objfile)
+ if result is not None:
+ return result
+
+ return None
diff --git a/gdb/python/lib/gdb/command/missing_debug.py b/gdb/python/lib/gdb/command/missing_debug.py
new file mode 100644
--- /dev/null
+++ b/gdb/python/lib/gdb/command/missing_debug.py
@@ -0,0 +1,226 @@
+# Missing debug related commands.
+#
+# Copyright 2023 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/>.
+
+import gdb
+import re
+
+
+def validate_regexp(exp, idstring):
+ """Compile exp into a compiler regular expression object.
+
+ Arguments:
+ exp: The string to compile into a re.Pattern object.
+ idstring: A string, what exp is a regexp for.
+
+ Returns:
+ A re.Pattern object representing exp.
+
+ Raises:
+ SyntaxError: If exp is an invalid regexp.
+ """
+ try:
+ return re.compile(exp)
+ except SyntaxError:
+ raise SyntaxError("Invalid %s regexp: %s." % (idstring, exp))
+
+
+def parse_missing_debug_command_args(arg):
+ """Internal utility to parse missing debug handler command argv.
+
+ Arguments:
+ arg: The arguments to the command. The format is:
+ [locus-regexp [name-regexp]]
+
+ Returns:
+ A 2-tuple of compiled regular expressions.
+
+ Raises:
+ SyntaxError: an error processing ARG
+ """
+ argv = gdb.string_to_argv(arg)
+ argc = len(argv)
+ if argc > 2:
+ raise SyntaxError("Too many arguments.")
+ locus_regexp = ""
+ name_regexp = ""
+ if argc >= 1:
+ locus_regexp = argv[0]
+ if argc >= 2:
+ name_regexp = argv[1]
+ return (
+ validate_regexp(locus_regexp, "locus"),
+ validate_regexp(name_regexp, "handler"),
+ )
+
+
+class InfoMissingDebugHanders(gdb.Command):
+ """GDB command to list missing debug handlers.
+
+ Usage: info missing-debug-handlers [LOCUS-REGEXP [NAME-REGEXP]]
+
+ LOCUS-REGEXP is a regular expression matching the location of the
+ handler. If it is omitted, all registered handlers from all
+ loci are listed. A locus can be 'global', 'progspace' to list
+ the handlers from the current progspace, or a regular expression
+ matching filenames of progspaces.
+
+ NAME-REGEXP is a regular expression to filter missing debug
+ handler names. If this omitted for a specified locus, then all
+ registered handlers in the locus are listed.
+ """
+
+ def __init__(self):
+ super().__init__("info missing-debug-handlers", gdb.COMMAND_FILES)
+
+ def list_handlers(self, title, handlers, name_re):
+ """Lists the missing debug handlers whose name matches regexp.
+
+ Arguments:
+ title: The line to print before the list.
+ handlers: The list of the missing debug handlers.
+ name_re: handler name filter.
+ """
+ if not handlers:
+ return
+ print(title)
+ for handler in handlers:
+ if name_re.match(handler.name):
+ print(
+ " %s%s" % (handler.name, "" if handler.enabled else " [disabled]")
+ )
+
+ def invoke(self, arg, from_tty):
+ locus_re, name_re = parse_missing_debug_command_args(arg)
+
+ if locus_re.match("progspace") and locus_re.pattern != "":
+ cp = gdb.current_progspace()
+ self.list_handlers(
+ "Progspace %s:" % cp.filename, cp.missing_debug_handlers, name_re
+ )
+
+ for progspace in gdb.progspaces():
+ filename = progspace.filename or ""
+ if locus_re.match(filename):
+ if filename == "":
+ if progspace == gdb.current_progspace():
+ msg = "Current Progspace:"
+ else:
+ msg = "Progspace <no-file>:"
+ else:
+ msg = "Progspace %s:" % filename
+ self.list_handlers(
+ msg,
+ progspace.missing_debug_handlers,
+ name_re,
+ )
+
+ # Print global handlers last, as these are invoked last.
+ if locus_re.match("global"):
+ self.list_handlers("Global:", gdb.missing_debug_handlers, name_re)
+
+
+def do_enable_handler1(handlers, name_re, flag):
+ """Enable/disable missing debug handlers whose names match given regex.
+
+ Arguments:
+ handlers: The list of missing debug handlers.
+ name_re: Handler name filter.
+ flag: A boolean indicating if we should enable or disable.
+
+ Returns:
+ The number of handlers affected.
+ """
+ total = 0
+ for handler in handlers:
+ if name_re.match(handler.name) and handler.enabled != flag:
+ handler.enabled = flag
+ total += 1
+ return total
+
+
+def do_enable_handler(arg, flag):
+ """Enable or disable missing debug handlers."""
+ (locus_re, name_re) = parse_missing_debug_command_args(arg)
+ total = 0
+ if locus_re.match("global"):
+ total += do_enable_handler1(gdb.missing_debug_handlers, name_re, flag)
+ if locus_re.match("progspace") and locus_re.pattern != "":
+ total += do_enable_handler1(
+ gdb.current_progspace().missing_debug_handlers, name_re, flag
+ )
+ for progspace in gdb.progspaces():
+ filename = progspace.filename or ""
+ if locus_re.match(filename):
+ total += do_enable_handler1(progspace.missing_debug_handlers, name_re, flag)
+ print(
+ "%d missing debug handler%s %s"
+ % (total, "" if total == 1 else "s", "enabled" if flag else "disabled")
+ )
+
+
+class EnableMissingDebugHandler(gdb.Command):
+ """GDB command to enable missing debug handlers.
+
+ Usage: enable missing-debug-handler [LOCUS-REGEXP [NAME-REGEXP]]
+
+ LOCUS-REGEXP is a regular expression specifying the handlers to
+ enable. It can be 'global', 'progspace' for the current
+ progspace, or the filename for a file associated with a progspace.
+
+ NAME_REGEXP is a regular expression to filter handler names. If
+ this omitted for a specified locus, then all registered handlers
+ in the locus are affected.
+ """
+
+ def __init__(self):
+ super().__init__("enable missing-debug-handler", gdb.COMMAND_FILES)
+
+ def invoke(self, arg, from_tty):
+ """GDB calls this to perform the command."""
+ do_enable_handler(arg, True)
+
+
+class DisableMissingDebugHandler(gdb.Command):
+ """GDB command to disable missing debug handlers.
+
+ Usage: disable missing-debug-handler [LOCUS-REGEXP [NAME-REGEXP]]
+
+ LOCUS-REGEXP is a regular expression specifying the handlers to
+ enable. It can be 'global', 'progspace' for the current
+ progspace, or the filename for a file associated with a progspace.
+
+ NAME_REGEXP is a regular expression to filter handler names. If
+ this omitted for a specified locus, then all registered handlers
+ in the locus are affected.
+ """
+
+ def __init__(self):
+ super().__init__("disable missing-debug-handler", gdb.COMMAND_FILES)
+
+ def invoke(self, arg, from_tty):
+ """GDB calls this to perform the command."""
+ do_enable_handler(arg, False)
+
+
+def register_missing_debug_handler_commands():
+ """Installs the missing debug handler commands."""
+ InfoMissingDebugHanders()
+ EnableMissingDebugHandler()
+ DisableMissingDebugHandler()
+
+
+register_missing_debug_handler_commands()
diff --git a/gdb/python/lib/gdb/missing_debug.py b/gdb/python/lib/gdb/missing_debug.py
new file mode 100644
--- /dev/null
+++ b/gdb/python/lib/gdb/missing_debug.py
@@ -0,0 +1,169 @@
+# Copyright (C) 2023 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/>.
+
+"""
+MissingDebugHandler base class, and register_handler function.
+"""
+
+import gdb
+
+
+def _validate_name(name):
+ """Validate a missing debug handler name string.
+
+ If name is valid as a missing debug handler name, then this
+ function does nothing. If name is not valid then an exception is
+ raised.
+
+ Arguments:
+ name: A string, the name of a missing debug handler.
+
+ Returns:
+ Nothing.
+
+ Raises:
+ ValueError: If name is invalid as a missing debug handler
+ name.
+ """
+ for ch in name:
+ if not ch.isascii() or not (ch.isalnum() or ch in "_-"):
+ raise ValueError("invalid character '%s' in handler name: %s" % (ch, name))
+
+
+class MissingDebugHandler(object):
+ """Base class for missing debug handlers written in Python.
+
+ A missing debug handler has a single method __call__ along with
+ the read/write attribute enabled, and a read-only attribute name.
+
+ Attributes:
+ name: Read-only attribute, the name of this handler.
+ enabled: When true this handler is enabled.
+ """
+
+ def __init__(self, name):
+ """Constructor.
+
+ Args:
+ name: An identifying name for this handler.
+
+ Raises:
+ TypeError: name is not a string.
+ ValueError: name contains invalid characters.
+ """
+
+ if not isinstance(name, str):
+ raise TypeError("incorrect type for name: %s" % type(name))
+
+ _validate_name(name)
+
+ self._name = name
+ self._enabled = True
+
+ @property
+ def name(self):
+ return self._name
+
+ @property
+ def enabled(self):
+ return self._enabled
+
+ @enabled.setter
+ def enabled(self, value):
+ if not isinstance(value, bool):
+ raise TypeError("incorrect type for enabled attribute: %s" % type(value))
+ self._enabled = value
+
+ def __call__(self, objfile):
+ """GDB handle missing debug information for an objfile.
+
+ Arguments:
+ objfile: A gdb.Objfile for which GDB could not find any
+ debug information.
+
+ Returns:
+ True: GDB should try again to locate the debug information
+ for objfile, the handler may have installed the
+ missing information.
+ False: GDB should move on without the debug information
+ for objfile.
+ A string: GDB should load the file at the given path; it
+ contains the debug information for objfile.
+ None: This handler can't help with objfile. GDB should
+ try any other registered handlers.
+ """
+ raise NotImplementedError("MissingDebugHandler.__call__()")
+
+
+def register_handler(locus, handler, replace=False):
+ """Register handler in given locus.
+
+ The handler is prepended to the locus's missing debug handlers
+ list. The name of handler should be unique (or replace must be
+ True).
+
+ Arguments:
+ locus: Either a progspace, or None (in which case the unwinder
+ is registered globally).
+ handler: An object of a gdb.MissingDebugHandler subclass.
+
+ replace: If True, replaces existing handler with the same name
+ within locus. Otherwise, raises RuntimeException if
+ unwinder with the same name already exists.
+
+ Returns:
+ Nothing.
+
+ Raises:
+ RuntimeError: The name of handler is not unique.
+ TypeError: Bad locus type.
+ AttributeError: Required attributes of handler are missing.
+ """
+
+ if locus is None:
+ if gdb.parameter("verbose"):
+ gdb.write("Registering global %s handler ...\n" % handler.name)
+ locus = gdb
+ elif isinstance(locus, gdb.Progspace):
+ if gdb.parameter("verbose"):
+ gdb.write(
+ "Registering %s handler for %s ...\n" % (handler.name, locus.filename)
+ )
+ else:
+ raise TypeError("locus should be gdb.Progspace or None")
+
+ # Some sanity checks on HANDLER. Calling getattr will raise an
+ # exception if the attribute doesn't exist, which is what we want.
+ # These checks are not exhaustive; we don't check the attributes
+ # have the correct types, or the method has the correct signature,
+ # but this should catch some basic mistakes.
+ getattr(handler, "name")
+ getattr(handler, "enabled")
+ call_method = getattr(handler, "__call__")
+ if not callable(call_method):
+ raise AttributeError(
+ "'%s' object's '__call__' attribute is not callable"
+ % type(handler).__name__
+ )
+
+ i = 0
+ for needle in locus.missing_debug_handlers:
+ if needle.name == handler.name:
+ if replace:
+ del locus.missing_debug_handlers[i]
+ else:
+ raise RuntimeError("Handler %s already exists." % handler.name)
+ i += 1
+ locus.missing_debug_handlers.insert(0, handler)
diff --git a/gdb/python/py-progspace.c b/gdb/python/py-progspace.c
--- a/gdb/python/py-progspace.c
+++ b/gdb/python/py-progspace.c
@@ -54,6 +54,9 @@ struct pspace_object
/* The debug method list. */
PyObject *xmethods;
+
+ /* The missing debug handler list. */
+ PyObject *missing_debug_handlers;
};
extern PyTypeObject pspace_object_type
@@ -163,6 +166,7 @@ pspy_dealloc (PyObject *self)
Py_XDECREF (ps_self->frame_unwinders);
Py_XDECREF (ps_self->type_printers);
Py_XDECREF (ps_self->xmethods);
+ Py_XDECREF (ps_self->missing_debug_handlers);
Py_TYPE (self)->tp_free (self);
}
@@ -198,6 +202,10 @@ pspy_initialize (pspace_object *self)
if (self->xmethods == NULL)
return 0;
+ self->missing_debug_handlers = PyList_New (0);
+ if (self->missing_debug_handlers == nullptr)
+ return 0;
+
return 1;
}
@@ -352,6 +360,47 @@ pspy_get_xmethods (PyObject *o, void *ignore)
return self->xmethods;
}
+/* Return the list of missing debug handlers for this program space. */
+
+static PyObject *
+pspy_get_missing_debug_handlers (PyObject *o, void *ignore)
+{
+ pspace_object *self = (pspace_object *) o;
+
+ Py_INCREF (self->missing_debug_handlers);
+ return self->missing_debug_handlers;
+}
+
+/* Set this program space's list of missing debug handlers to HANDLERS. */
+
+static int
+pspy_set_missing_debug_handlers (PyObject *o, PyObject *handlers,
+ void *ignore)
+{
+ pspace_object *self = (pspace_object *) o;
+
+ if (handlers == nullptr)
+ {
+ PyErr_SetString (PyExc_TypeError,
+ "cannot delete the missing debug handlers list");
+ return -1;
+ }
+
+ if (!PyList_Check (handlers))
+ {
+ PyErr_SetString (PyExc_TypeError,
+ "the missing debug handlers attribute must be a list");
+ return -1;
+ }
+
+ /* Take care in case the LHS and RHS are related somehow. */
+ gdbpy_ref<> tmp (self->missing_debug_handlers);
+ Py_INCREF (handlers);
+ self->missing_debug_handlers = handlers;
+
+ return 0;
+}
+
/* Set the 'type_printers' attribute. */
static int
@@ -744,6 +793,8 @@ static gdb_PyGetSetDef pspace_getset[] =
"Type printers.", NULL },
{ "xmethods", pspy_get_xmethods, NULL,
"Debug methods.", NULL },
+ { "missing_debug_handlers", pspy_get_missing_debug_handlers,
+ pspy_set_missing_debug_handlers, "Missing debug handlers.", NULL },
{ NULL }
};
diff --git a/gdb/python/python.c b/gdb/python/python.c
--- a/gdb/python/python.c
+++ b/gdb/python/python.c
@@ -124,7 +124,9 @@ static enum ext_lang_rc gdbpy_before_prompt_hook
static gdb::optional<std::string> gdbpy_colorize
(const std::string &filename, const std::string &contents);
static gdb::optional<std::string> gdbpy_colorize_disasm
- (const std::string &content, gdbarch *gdbarch);
+(const std::string &content, gdbarch *gdbarch);
+static ext_lang_missing_debuginfo_result gdbpy_handle_missing_debuginfo
+ (const struct extension_language_defn *extlang, struct objfile *objfile);
/* The interface between gdb proper and loading of python scripts. */
@@ -170,6 +172,8 @@ static const struct extension_language_ops python_extension_ops =
gdbpy_colorize_disasm,
gdbpy_print_insn,
+
+ gdbpy_handle_missing_debuginfo
};
#endif /* HAVE_PYTHON */
@@ -1661,6 +1665,83 @@ gdbpy_get_current_objfile (PyObject *unused1, PyObject *unused2)
return objfile_to_objfile_object (gdbpy_current_objfile).release ();
}
+/* Implement the 'handle_missing_debuginfo' hook for Python. GDB has
+ failed to find any debug information for OBJFILE. The extension has a
+ chance to record this, or even install the required debug information.
+ See the description of ext_lang_missing_debuginfo_result in
+ extension-priv.h for details of the return value. */
+
+static ext_lang_missing_debuginfo_result
+gdbpy_handle_missing_debuginfo (const struct extension_language_defn *extlang,
+ struct objfile *objfile)
+{
+ /* Early exit if Python is not initialised. */
+ if (!gdb_python_initialized)
+ return {};
+
+ struct gdbarch *gdbarch = objfile->arch ();
+
+ gdbpy_enter enter_py (gdbarch);
+
+ /* Convert OBJFILE into the corresponding Python object. */
+ gdbpy_ref<> pyo_objfile = objfile_to_objfile_object (objfile);
+ if (pyo_objfile == nullptr)
+ {
+ gdbpy_print_stack ();
+ return {};
+ }
+
+ /* Lookup the helper function within the GDB module. */
+ gdbpy_ref<> pyo_handler
+ (PyObject_GetAttrString (gdb_python_module, "_handle_missing_debuginfo"));
+ if (pyo_handler == nullptr)
+ {
+ gdbpy_print_stack ();
+ return {};
+ }
+
+ /* Call the function, passing in the Python objfile object. */
+ gdbpy_ref<> pyo_execute_ret
+ (PyObject_CallFunctionObjArgs (pyo_handler.get (), pyo_objfile.get (),
+ nullptr));
+ if (pyo_execute_ret == nullptr)
+ {
+ /* If the handler is cancelled due to a Ctrl-C, then propagate
+ the Ctrl-C as a GDB exception instead of swallowing it. */
+ gdbpy_print_stack_or_quit ();
+ return {};
+ }
+
+ /* Parse the result, and convert it back to the C++ object. */
+ if (pyo_execute_ret == Py_None)
+ return {};
+
+ if (PyBool_Check (pyo_execute_ret.get ()))
+ {
+ bool try_again = PyObject_IsTrue (pyo_execute_ret.get ());
+ return ext_lang_missing_debuginfo_result (try_again);
+ }
+
+ if (!gdbpy_is_string (pyo_execute_ret.get ()))
+ {
+ PyErr_SetString (PyExc_ValueError,
+ "return value from _handle_missing_debuginfo should "
+ "be None, a Bool, or a String");
+ gdbpy_print_stack ();
+ return {};
+ }
+
+ gdb::unique_xmalloc_ptr<char> filename
+ = python_string_to_host_string (pyo_execute_ret.get ());
+ if (filename == nullptr)
+ {
+ gdbpy_print_stack ();
+ return {};
+ }
+
+ return ext_lang_missing_debuginfo_result (std::string (filename.get ()));
+}
+
/* Compute the list of active python type printers and store them in
EXT_PRINTERS->py_type_printers. The product of this function is used by
gdbpy_apply_type_printers, and freed by gdbpy_free_type_printers.
diff --git a/gdb/testsuite/gdb.python/py-missing-debug.c b/gdb/testsuite/gdb.python/py-missing-debug.c
new file mode 100644
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-missing-debug.c
@@ -0,0 +1,22 @@
+/* This test program is part of GDB, the GNU debugger.
+
+ Copyright 2023 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/>. */
+
+int
+main ()
+{
+ return 0;
+}
diff --git a/gdb/testsuite/gdb.python/py-missing-debug.exp b/gdb/testsuite/gdb.python/py-missing-debug.exp
new file mode 100644
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-missing-debug.exp
@@ -0,0 +1,473 @@
+# Copyright (C) 2023 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/>.
+
+load_lib gdb-python.exp
+
+require allow_python_tests
+
+standard_testfile
+
+if {[build_executable "failed to prepare" ${testfile} ${srcfile}]} {
+ return -1
+}
+
+# Remove debug information from BINFILE and place it into
+# BINFILE.debug.
+if {[gdb_gnu_strip_debug $binfile]} {
+ unsupported "cannot produce separate debug info files"
+ return -1
+}
+
+set remote_python_file \
+ [gdb_remote_download host ${srcdir}/${subdir}/${testfile}.py]
+
+set debug_filename ${binfile}.debug
+set hidden_filename ${binfile}.hidden
+
+# Start GDB.
+clean_restart
+
+# Some initial sanity checks; initially, we can find the debug information
+# (this will use the .gnu_debuglink), then after we move the debug
+# information, reload the executable, now the debug can't be found.
+with_test_prefix "initial checks" {
+ # Load BINFILE, we should find the separate debug information.
+ gdb_file_cmd $binfile
+ gdb_assert {$gdb_file_cmd_debug_info == "debug"} \
+ "debug info is found"
+
+ # Rename the debug information file, re-load BINFILE, GDB should fail
+ # to find the debug information
+ remote_exec build "mv $debug_filename $hidden_filename"
+ gdb_file_cmd $binfile
+ gdb_assert {$gdb_file_cmd_debug_info == "nodebug"} \
+ "debug info no longer found"
+}
+
+# Load the Python script into GDB.
+gdb_test "source $remote_python_file" "^Success" \
+ "source python script"
+
+# Setup the separate debug info directory. This isn't actually needed until
+# some of the later tests, but might as well get this done now.
+set debug_directory [standard_output_file "debug-dir"]
+remote_exec build "mkdir -p $debug_directory"
+gdb_test_no_output "set debug-file-directory $debug_directory" \
+ "set debug-file-directory"
+
+# Initially the missing debug handler we install is in a mode where it
+# returns None, indicating that it can't help locate the debug information.
+# Check this works as expected.
+with_test_prefix "handler returning None" {
+ gdb_test_no_output \
+ "python gdb.missing_debug.register_handler(None, handler_obj)" \
+ "register the initial handler"
+
+ gdb_file_cmd $binfile
+ gdb_assert {$gdb_file_cmd_debug_info == "nodebug"} \
+ "debug info not found"
+
+ # Check the handler was only called once.
+ gdb_test "python print(handler_obj.call_count)" "^1" \
+ "check handler was only called once"
+}
+
+# Now configure the handler to move the debug file back to the
+# .gnu_debuglink location and then return True, this will cause GDB to
+# recheck, at which point it should find the debug info.
+with_test_prefix "handler in gnu_debuglink mode" {
+ gdb_test_no_output "python handler_obj.set_mode(Mode.RETURN_TRUE, \
+ \"$hidden_filename\", \
+ \"$debug_filename\")" \
+ "confirgure handler"
+ gdb_file_cmd $binfile
+ gdb_assert {$gdb_file_cmd_debug_info == "debug"} "debug info found"
+
+ # Check the handler was only called once.
+ gdb_test "python print(handler_obj.call_count)" "^1" \
+ "check handler was only called once"
+}
+
+# Setup a directory structure based on the build-id of BINFILE, but don't
+# move the debug information into place just yet.
+#
+# Instead, configure the handler to move the debug info into the build-id
+# directory.
+#
+# Reload BINFILE, at which point the handler will move the debug info into
+# the build-id directory and return True, GDB will then recheck for the
+# debug information, and should find it.
+with_test_prefix "handler in build-id mode" {
+ # Move the debug file out of the way once more.
+ remote_exec build "mv $debug_filename $hidden_filename"
+
+ # Create the build-id based directory in which the debug information
+ # will be placed.
+ set build_id_filename \
+ $debug_directory/[build_id_debug_filename_get $binfile]
+ remote_exec build "mkdir -p [file dirname $build_id_filename]"
+
+ # Configure the handler to move the debug info into the build-id dir.
+ gdb_test_no_output "python handler_obj.set_mode(Mode.RETURN_TRUE, \
+ \"$hidden_filename\", \
+ \"$build_id_filename\")" \
+ "confirgure handler"
+
+ # Reload the binary and check the debug information is found.
+ gdb_file_cmd $binfile
+ gdb_assert {$gdb_file_cmd_debug_info == "debug"} "debug info found"
+
+ # Check the handler was only called once.
+ gdb_test "python print(handler_obj.call_count)" "^1" \
+ "check handler was only called once"
+}
+
+# Move the debug information back to a hidden location and configure the
+# handler to return the filename of the hidden debug info location. GDB
+# should immediately use this file as the debug information.
+with_test_prefix "handler returning a string" {
+ remote_exec build "mv $build_id_filename $hidden_filename"
+
+ # Configure the handler return a filename string.
+ gdb_test_no_output "python handler_obj.set_mode(Mode.RETURN_STRING, \
+ \"$hidden_filename\")" \
+ "confirgure handler"
+
+ # Reload the binary and check the debug information is found.
+ gdb_file_cmd $binfile
+ gdb_assert {$gdb_file_cmd_debug_info == "debug"} "debug info found"
+
+ # Check the handler was only called once.
+ gdb_test "python print(handler_obj.call_count)" "^1" \
+ "check handler was only called once"
+}
+
+# Register another global handler, this one raises an exception. Reload the
+# debug information, the bad handler should be invoked first, which raises
+# an excetption, at which point GDB should skip further Python handlers.
+with_test_prefix "handler raises an exception" {
+ gdb_test_no_output \
+ "python gdb.missing_debug.register_handler(None, rhandler)"
+
+ foreach_with_prefix exception_type {gdb.GdbError TypeError} {
+ gdb_test_no_output \
+ "python rhandler.exception_type = $exception_type"
+
+ gdb_file_cmd $binfile
+ gdb_assert {$gdb_file_cmd_debug_info == "nodebug"} \
+ "debug info not found"
+
+ set re [string_to_regexp \
+ "Python Exception <class '$exception_type'>: message"]
+ gdb_assert {[regexp $re $gdb_file_cmd_msg]} \
+ "check for exception in file command output"
+
+ # Our original handler is still registered, but should not have been
+ # called again (as the exception occurs first).
+ gdb_test "python print(handler_obj.call_count)" "^1" \
+ "check good handler hasn't been called again"
+ }
+}
+
+gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Global:" \
+ " exception_handler" \
+ " handler"] \
+ "check both handlers are visible"
+
+# Re-start GDB.
+clean_restart
+
+# Load the Python script into GDB.
+gdb_test "source $remote_python_file" "^Success" \
+ "source python script for bad handler name checks"
+
+# Attempt to register a missing-debug-handler with NAME. The expectation is
+# that this should fail as NAME contains some invalid characters.
+proc check_bad_name {name} {
+ set name_re [string_to_regexp $name]
+ set re \
+ [multi_line \
+ "ValueError: invalid character '.' in handler name: $name_re" \
+ "Error while executing Python code\\."]
+
+ gdb_test "python register(\"$name\")" $re \
+ "check that '$name' is not accepted"
+}
+
+# We don't attempt to be exhaustive here, just check a few random examples
+# of invalid names.
+check_bad_name "!! Bad Name"
+check_bad_name "Bad Name"
+check_bad_name "(Bad Name)"
+check_bad_name "Bad \[Name\]"
+check_bad_name "Bad,Name"
+check_bad_name "Bad;Name"
+
+# Check that there are no handlers registered.
+gdb_test_no_output "info missing-debug-handlers" \
+ "check no handlers are registered"
+
+# Check we can use the enable/disable commands where there are no handlers
+# registered.
+gdb_test "enable missing-debug-handler foo" \
+ "^0 missing debug handlers enabled"
+gdb_test "disable missing-debug-handler foo" \
+ "^0 missing debug handlers disabled"
+
+# Grab the current program space object, used for registering handler later.
+gdb_test_no_output "python pspace = gdb.selected_inferior().progspace"
+
+# Now register some handlers.
+foreach hspec {{\"Foo\" None}
+ {\"-bar\" None}
+ {\"baz-\" pspace}
+ {\"abc-def\" pspace}} {
+ lassign $hspec name locus
+ gdb_test "python register($name, $locus)"
+}
+
+with_test_prefix "all handlers enabled" {
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Current Progspace:" \
+ " abc-def" \
+ " baz-" \
+ "Global:" \
+ " -bar" \
+ " Foo"]
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {['abc-def', 'baz-', '-bar', 'Foo']}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+with_test_prefix "disable 'baz-'" {
+ gdb_test "disable missing-debug-handler progspace baz-" \
+ "^1 missing debug handler disabled"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " abc-def" \
+ " baz- \\\[disabled\\\]" \
+ "Global:" \
+ " -bar" \
+ " Foo"]
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {['abc-def', '-bar', 'Foo']}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+with_test_prefix "disable 'Foo'" {
+ gdb_test "disable missing-debug-handler .* Foo" \
+ "^1 missing debug handler disabled"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " abc-def" \
+ " baz- \\\[disabled\\\]" \
+ "Global:" \
+ " -bar" \
+ " Foo \\\[disabled\\\]"]
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {['abc-def', '-bar']}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+with_test_prefix "disable everything" {
+ gdb_test "disable missing-debug-handler .* .*" \
+ "^2 missing debug handlers disabled"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " abc-def \\\[disabled\\\]" \
+ " baz- \\\[disabled\\\]" \
+ "Global:" \
+ " -bar \\\[disabled\\\]" \
+ " Foo \\\[disabled\\\]"]
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {[]}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+with_test_prefix "enable 'abc-def'" {
+ set re [string_to_regexp $binfile]
+
+ gdb_test "enable missing-debug-handler \"$re\" abc-def" \
+ "^1 missing debug handler enabled"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " abc-def" \
+ " baz- \\\[disabled\\\]" \
+ "Global:" \
+ " -bar \\\[disabled\\\]" \
+ " Foo \\\[disabled\\\]"]
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {['abc-def']}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+with_test_prefix "enable global handlers" {
+ set re [string_to_regexp $binfile]
+
+ gdb_test "enable missing-debug-handler global" \
+ "^2 missing debug handlers enabled"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " abc-def" \
+ " baz- \\\[disabled\\\]" \
+ "Global:" \
+ " -bar" \
+ " Foo"]
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {['abc-def', '-bar', 'Foo']}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+# Add handler_obj to the global handler list, and configure it to
+# return False. We should call all of the program space specific
+# handlers (which return None), and then call handler_obj from the
+# global list, which returns False, at which point we shouldn't call
+# anyone else.
+with_test_prefix "return False handler in progspace list" {
+ gdb_test "enable missing-debug-handler progspace" \
+ "^1 missing debug handler enabled"
+
+ gdb_test_no_output \
+ "python gdb.missing_debug.register_handler(None, handler_obj)" \
+ "register the initial handler"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " abc-def" \
+ " baz-" \
+ "Global:" \
+ " handler" \
+ " -bar" \
+ " Foo"]
+
+ gdb_test_no_output "python handler_obj.set_mode(Mode.RETURN_FALSE)" \
+ "confirgure handler"
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {['abc-def', 'baz-', 'handler']}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+# Now add handler_obj to the current program space's handler list. We
+# use the same handler object here, that's fine. We should only see a
+# call to the first handler object in the call log.
+with_test_prefix "return False handler in global list" {
+ gdb_test_no_output \
+ "python gdb.missing_debug.register_handler(pspace, handler_obj)" \
+ "register the initial handler"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " handler" \
+ " abc-def" \
+ " baz-" \
+ "Global:" \
+ " handler" \
+ " -bar" \
+ " Foo"]
+
+ gdb_file_cmd $binfile
+ gdb_test "python print(handler_call_log)" \
+ [string_to_regexp {['handler']}]
+ gdb_test_no_output "python handler_call_log = \[\]" \
+ "reset call log"
+}
+
+with_test_prefix "check handler replacement" {
+ # First, check we can have the same name appear in both program
+ # space and global lists without giving an error.
+ gdb_test_no_output "python register(\"Foo\", pspace)"
+
+ gdb_test "info missing-debug-handlers" \
+ [multi_line \
+ "Progspace \[^\r\n\]+:" \
+ " Foo" \
+ " handler" \
+ " abc-def" \
+ " baz-" \
+ "Global:" \
+ " handler" \
+ " -bar" \
+ " Foo"]
+
+ # Now check that we get an error if we try to add a handler with
+ # the same name.
+ gdb_test "python gdb.missing_debug.register_handler(pspace, log_handler(\"Foo\"))" \
+ [multi_line \
+ "RuntimeError: Handler Foo already exists\\." \
+ "Error while executing Python code\\."]
+
+ gdb_test "python gdb.missing_debug.register_handler(handler=log_handler(\"Foo\"), locus=pspace)" \
+ [multi_line \
+ "RuntimeError: Handler Foo already exists\\." \
+ "Error while executing Python code\\."]
+
+ # And now try again, but this time with 'replace=True', we
+ # shouldn't get an error in this case.
+ gdb_test_no_output \
+ "python gdb.missing_debug.register_handler(pspace, log_handler(\"Foo\"), replace=True)"
+
+ gdb_test_no_output \
+ "python gdb.missing_debug.register_handler(handler=log_handler(\"Foo\"), locus=None, replace=True)"
+
+ # Now disable a handler and check we still need to use 'replace=True'.
+ gdb_test "disable missing-debug-handler progspace Foo" \
+ "^1 missing debug handler disabled"
+
+ gdb_test "python gdb.missing_debug.register_handler(pspace, log_handler(\"Foo\"))" \
+ [multi_line \
+ "RuntimeError: Handler Foo already exists\\." \
+ "Error while executing Python code\\."] \
+ "still get an error when handler is disabled"
+
+ gdb_test_no_output \
+ "python gdb.missing_debug.register_handler(pspace, log_handler(\"Foo\"), replace=True)" \
+ "can replace a disabled handler"
+}
diff --git a/gdb/testsuite/gdb.python/py-missing-debug.py b/gdb/testsuite/gdb.python/py-missing-debug.py
new file mode 100644
--- /dev/null
+++ b/gdb/testsuite/gdb.python/py-missing-debug.py
@@ -0,0 +1,120 @@
+# Copyright (C) 2023 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/>.
+
+import gdb
+from gdb.missing_debug import MissingDebugHandler
+from enum import Enum
+import os
+
+# A global log that is filled in by instances of the LOG_HANDLER class
+# when they are called.
+handler_call_log = []
+
+
+class Mode(Enum):
+ RETURN_NONE = 0
+ RETURN_TRUE = 1
+ RETURN_FALSE = 2
+ RETURN_STRING = 3
+
+
+class handler(MissingDebugHandler):
+ def __init__(self):
+ super().__init__("handler")
+ self._call_count = 0
+ self._mode = Mode.RETURN_NONE
+
+ def __call__(self, objfile):
+ global handler_call_log
+ handler_call_log.append(self.name)
+ self._call_count += 1
+ if self._mode == Mode.RETURN_NONE:
+ return None
+
+ if self._mode == Mode.RETURN_TRUE:
+ os.rename(self._src, self._dest)
+ return True
+
+ if self._mode == Mode.RETURN_FALSE:
+ return False
+
+ if self._mode == Mode.RETURN_STRING:
+ return self._dest
+
+ assert False
+
+ @property
+ def call_count(self):
+ """Return a count, the number of calls to __call__ since the last
+ call to set_mode.
+ """
+ return self._call_count
+
+ def set_mode(self, mode, *args):
+ self._call_count = 0
+ self._mode = mode
+
+ if mode == Mode.RETURN_NONE:
+ assert len(args) == 0
+ return
+
+ if mode == Mode.RETURN_TRUE:
+ assert len(args) == 2
+ self._src = args[0]
+ self._dest = args[1]
+ return
+
+ if mode == Mode.RETURN_FALSE:
+ assert len(args) == 0
+ return
+
+ if mode == Mode.RETURN_STRING:
+ assert len(args) == 1
+ self._dest = args[0]
+ return
+
+ assert False
+
+
+class exception_handler(MissingDebugHandler):
+ def __init__(self):
+ super().__init__("exception_handler")
+ self.exception_type = None
+
+ def __call__(self, objfile):
+ global handler_call_log
+ handler_call_log.append(self.name)
+ assert self.exception_type is not None
+ raise self.exception_type("message")
+
+
+class log_handler(MissingDebugHandler):
+ def __call__(self, objfile):
+ global handler_call_log
+ handler_call_log.append(self.name)
+ return None
+
+
+# A basic helper function, this keeps lines shorter in the TCL script.
+def register(name, locus=None):
+ gdb.missing_debug.register_handler(locus, log_handler(name))
+
+
+# Create instances of the handlers, but don't install any. We install
+# these as needed from the TCL script.
+rhandler = exception_handler()
+handler_obj = handler()
+
+print("Success")