gdb/python/lib/gdb/__init__.py - binutils-gdb - Git at Google

 # Copyright (C) 2010-2024 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 os
 import signal
 import sys
 import threading
 import traceback
 from contextlib import contextmanager

 # Python 3 moved "reload"
 if sys.version_info >= (3, 4):
     from importlib import reload
 else:
     from imp import reload

 import _gdb

 # Note that two indicators are needed here to silence flake8.
 from _gdb import *  # noqa: F401,F403

 # isort: split

 # Historically, gdb.events was always available, so ensure it's
 # still available without an explicit import.
 import _gdbevents as events

 sys.modules["gdb.events"] = events


 class _GdbFile(object):
     # These two are needed in Python 3
     encoding = "UTF-8"
     errors = "strict"

     def __init__(self, stream):
         self.stream = stream

     def close(self):
         # Do nothing.
         return None

     def isatty(self):
         return False

     def writelines(self, iterable):
         for line in iterable:
             self.write(line)

     def flush(self):
         _gdb.flush(stream=self.stream)

     def write(self, s):
         _gdb.write(s, stream=self.stream)


 sys.stdout = _GdbFile(_gdb.STDOUT)
 sys.stderr = _GdbFile(_gdb.STDERR)

 # Default prompt hook does nothing.
 prompt_hook = None

 # Ensure that sys.argv is set to something.
 # We do not use PySys_SetArgvEx because it did not appear until 2.6.6.
 sys.argv = [""]

 # Initial pretty printers.
 pretty_printers = []

 # Initial type printers.
 type_printers = []
 # Initial xmethod matchers.
 xmethods = []
 # Initial frame filters.
 frame_filters = {}
 # Initial frame unwinders.
 frame_unwinders = []
 # Initial missing debug handlers.
 missing_debug_handlers = []


 def _execute_unwinders(pending_frame):
     """Internal function called from GDB to execute all unwinders.

     Runs each currently enabled unwinder until it finds the one that
     can unwind given frame.

     Arguments:
         pending_frame: gdb.PendingFrame instance.

     Returns:
         Tuple with:

           [0] gdb.UnwindInfo instance
           [1] Name of unwinder that claimed the frame (type `str`)

         or None, if no unwinder has claimed the frame.
     """
     for objfile in objfiles():
         for unwinder in objfile.frame_unwinders:
             if unwinder.enabled:
                 unwind_info = unwinder(pending_frame)
                 if unwind_info is not None:
                     return (unwind_info, unwinder.name)

     for unwinder in current_progspace().frame_unwinders:
         if unwinder.enabled:
             unwind_info = unwinder(pending_frame)
             if unwind_info is not None:
                 return (unwind_info, unwinder.name)

     for unwinder in frame_unwinders:
         if unwinder.enabled:
             unwind_info = unwinder(pending_frame)
             if unwind_info is not None:
                 return (unwind_info, unwinder.name)

     return None


 # Convenience variable to GDB's python directory
 PYTHONDIR = os.path.dirname(os.path.dirname(__file__))

 # Auto-load all functions/commands.

 # Packages to auto-load.

 packages = ["function", "command", "printer"]

 # pkgutil.iter_modules is not available prior to Python 2.6.  Instead,
 # manually iterate the list, collating the Python files in each module
 # path.  Construct the module name, and import.


 def _auto_load_packages():
     for package in packages:
         location = os.path.join(os.path.dirname(__file__), package)
         if os.path.exists(location):
             py_files = filter(
                 lambda x: x.endswith(".py") and x != "__init__.py", os.listdir(location)
             )

             for py_file in py_files:
                 # Construct from foo.py, gdb.module.foo
                 modname = "%s.%s.%s" % (__name__, package, py_file[:-3])
                 try:
                     if modname in sys.modules:
                         # reload modules with duplicate names
                         reload(__import__(modname))
                     else:
                         __import__(modname)
                 except Exception:
                     sys.stderr.write(traceback.format_exc() + "\n")


 _auto_load_packages()


 def GdbSetPythonDirectory(dir):
     """Update sys.path, reload gdb and auto-load packages."""
     global PYTHONDIR

     try:
         sys.path.remove(PYTHONDIR)
     except ValueError:
         pass
     sys.path.insert(0, dir)

     PYTHONDIR = dir

     # note that reload overwrites the gdb module without deleting existing
     # attributes
     reload(__import__(__name__))
     _auto_load_packages()


 def current_progspace():
     "Return the current Progspace."
     return _gdb.selected_inferior().progspace


 def objfiles():
     "Return a sequence of the current program space's objfiles."
     return current_progspace().objfiles()


 def solib_name(addr):
     """solib_name (Long) -> String.\n\
 Return the name of the shared library holding a given address, or None."""
     return current_progspace().solib_name(addr)


 def block_for_pc(pc):
     "Return the block containing the given pc value, or None."
     return current_progspace().block_for_pc(pc)


 def find_pc_line(pc):
     """find_pc_line (pc) -> Symtab_and_line.
     Return the gdb.Symtab_and_line object corresponding to the pc value."""
     return current_progspace().find_pc_line(pc)


 def set_parameter(name, value):
     """Set the GDB parameter NAME to VALUE."""
     # Handle the specific cases of None and booleans here, because
     # gdb.parameter can return them, but they can't be passed to 'set'
     # this way.
     if value is None:
         value = "unlimited"
     elif isinstance(value, bool):
         if value:
             value = "on"
         else:
             value = "off"
     _gdb.execute("set " + name + " " + str(value), to_string=True)


 @contextmanager
 def with_parameter(name, value):
     """Temporarily set the GDB parameter NAME to VALUE.
     Note that this is a context manager."""
     old_value = _gdb.parameter(name)
     set_parameter(name, value)
     try:
         # Nothing that useful to return.
         yield None
     finally:
         set_parameter(name, old_value)


 @contextmanager
 def blocked_signals():
     """A helper function that blocks and unblocks signals."""
     if not hasattr(signal, "pthread_sigmask"):
         yield
         return

     to_block = {signal.SIGCHLD, signal.SIGINT, signal.SIGALRM, signal.SIGWINCH}
     old_mask = signal.pthread_sigmask(signal.SIG_BLOCK, to_block)
     try:
         yield None
     finally:
         signal.pthread_sigmask(signal.SIG_SETMASK, old_mask)


 class Thread(threading.Thread):
     """A GDB-specific wrapper around threading.Thread

     This wrapper ensures that the new thread blocks any signals that
     must be delivered on GDB's main thread."""

     def start(self):
         # GDB requires that these be delivered to the main thread.  We
         # do this here to avoid any possible race with the creation of
         # the new thread.  The thread mask is inherited by new
         # 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
	# Copyright (C) 2010-2024 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 os
	import signal
	import sys
	import threading
	import traceback
	from contextlib import contextmanager

	# Python 3 moved "reload"
	if sys.version_info >= (3, 4):
	from importlib import reload
	else:
	from imp import reload

	import _gdb

	# Note that two indicators are needed here to silence flake8.
	from _gdb import * # noqa: F401,F403

	# isort: split

	# Historically, gdb.events was always available, so ensure it's
	# still available without an explicit import.
	import _gdbevents as events

	sys.modules["gdb.events"] = events


	class _GdbFile(object):
	# These two are needed in Python 3
	encoding = "UTF-8"
	errors = "strict"

	def __init__(self, stream):
	self.stream = stream

	def close(self):
	# Do nothing.
	return None

	def isatty(self):
	return False

	def writelines(self, iterable):
	for line in iterable:
	self.write(line)

	def flush(self):
	_gdb.flush(stream=self.stream)

	def write(self, s):
	_gdb.write(s, stream=self.stream)


	sys.stdout = _GdbFile(_gdb.STDOUT)
	sys.stderr = _GdbFile(_gdb.STDERR)

	# Default prompt hook does nothing.
	prompt_hook = None

	# Ensure that sys.argv is set to something.
	# We do not use PySys_SetArgvEx because it did not appear until 2.6.6.
	sys.argv = [""]

	# Initial pretty printers.
	pretty_printers = []

	# Initial type printers.
	type_printers = []
	# Initial xmethod matchers.
	xmethods = []
	# Initial frame filters.
	frame_filters = {}
	# Initial frame unwinders.
	frame_unwinders = []
	# Initial missing debug handlers.
	missing_debug_handlers = []


	def _execute_unwinders(pending_frame):
	"""Internal function called from GDB to execute all unwinders.

	Runs each currently enabled unwinder until it finds the one that
	can unwind given frame.

	Arguments:
	pending_frame: gdb.PendingFrame instance.

	Returns:
	Tuple with:

	[0] gdb.UnwindInfo instance
	[1] Name of unwinder that claimed the frame (type `str`)

	or None, if no unwinder has claimed the frame.
	"""
	for objfile in objfiles():
	for unwinder in objfile.frame_unwinders:
	if unwinder.enabled:
	unwind_info = unwinder(pending_frame)
	if unwind_info is not None:
	return (unwind_info, unwinder.name)

	for unwinder in current_progspace().frame_unwinders:
	if unwinder.enabled:
	unwind_info = unwinder(pending_frame)
	if unwind_info is not None:
	return (unwind_info, unwinder.name)

	for unwinder in frame_unwinders:
	if unwinder.enabled:
	unwind_info = unwinder(pending_frame)
	if unwind_info is not None:
	return (unwind_info, unwinder.name)

	return None


	# Convenience variable to GDB's python directory
	PYTHONDIR = os.path.dirname(os.path.dirname(__file__))

	# Auto-load all functions/commands.

	# Packages to auto-load.

	packages = ["function", "command", "printer"]

	# pkgutil.iter_modules is not available prior to Python 2.6. Instead,
	# manually iterate the list, collating the Python files in each module
	# path. Construct the module name, and import.


	def _auto_load_packages():
	for package in packages:
	location = os.path.join(os.path.dirname(__file__), package)
	if os.path.exists(location):
	py_files = filter(
	lambda x: x.endswith(".py") and x != "__init__.py", os.listdir(location)
	)

	for py_file in py_files:
	# Construct from foo.py, gdb.module.foo
	modname = "%s.%s.%s" % (__name__, package, py_file[:-3])
	try:
	if modname in sys.modules:
	# reload modules with duplicate names
	reload(__import__(modname))
	else:
	__import__(modname)
	except Exception:
	sys.stderr.write(traceback.format_exc() + "\n")


	_auto_load_packages()


	def GdbSetPythonDirectory(dir):
	"""Update sys.path, reload gdb and auto-load packages."""
	global PYTHONDIR

	try:
	sys.path.remove(PYTHONDIR)
	except ValueError:
	pass
	sys.path.insert(0, dir)

	PYTHONDIR = dir

	# note that reload overwrites the gdb module without deleting existing
	# attributes
	reload(__import__(__name__))
	_auto_load_packages()


	def current_progspace():
	"Return the current Progspace."
	return _gdb.selected_inferior().progspace


	def objfiles():
	"Return a sequence of the current program space's objfiles."
	return current_progspace().objfiles()


	def solib_name(addr):
	"""solib_name (Long) -> String.\n\
	Return the name of the shared library holding a given address, or None."""
	return current_progspace().solib_name(addr)


	def block_for_pc(pc):
	"Return the block containing the given pc value, or None."
	return current_progspace().block_for_pc(pc)


	def find_pc_line(pc):
	"""find_pc_line (pc) -> Symtab_and_line.
	Return the gdb.Symtab_and_line object corresponding to the pc value."""
	return current_progspace().find_pc_line(pc)


	def set_parameter(name, value):
	"""Set the GDB parameter NAME to VALUE."""
	# Handle the specific cases of None and booleans here, because
	# gdb.parameter can return them, but they can't be passed to 'set'
	# this way.
	if value is None:
	value = "unlimited"
	elif isinstance(value, bool):
	if value:
	value = "on"
	else:
	value = "off"
	_gdb.execute("set " + name + " " + str(value), to_string=True)


	@contextmanager
	def with_parameter(name, value):
	"""Temporarily set the GDB parameter NAME to VALUE.
	Note that this is a context manager."""
	old_value = _gdb.parameter(name)
	set_parameter(name, value)
	try:
	# Nothing that useful to return.
	yield None
	finally:
	set_parameter(name, old_value)


	@contextmanager
	def blocked_signals():
	"""A helper function that blocks and unblocks signals."""
	if not hasattr(signal, "pthread_sigmask"):
	yield
	return

	to_block = {signal.SIGCHLD, signal.SIGINT, signal.SIGALRM, signal.SIGWINCH}
	old_mask = signal.pthread_sigmask(signal.SIG_BLOCK, to_block)
	try:
	yield None
	finally:
	signal.pthread_sigmask(signal.SIG_SETMASK, old_mask)


	class Thread(threading.Thread):
	"""A GDB-specific wrapper around threading.Thread

	This wrapper ensures that the new thread blocks any signals that
	must be delivered on GDB's main thread."""

	def start(self):
	# GDB requires that these be delivered to the main thread. We
	# do this here to avoid any possible race with the creation of
	# the new thread. The thread mask is inherited by new
	# 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