Med Ismail Bennani 312b43da05 [lldb/Plugins] Add ScriptedProcess Process Plugin
This patch introduces Scripted Processes to lldb.

The goal, here, is to be able to attach in the debugger to fake processes
that are backed by script files (in Python, Lua, Swift, etc ...) and
inspect them statically.

Scripted Processes can be used in cooperative multithreading environments
like the XNU Kernel or other real-time operating systems, but it can
also help us improve the debugger testing infrastructure by writting
synthetic tests that simulates hard-to-reproduce process/thread states.

Although ScriptedProcess is not feature-complete at the moment, it has
basic execution capabilities and will improve in the following patches.

rdar://65508855

Differential Revision: https://reviews.llvm.org/D100384

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-07-22 14:47:33 +02:00

166 lines
4.7 KiB
Python

from abc import ABCMeta, abstractmethod
import six
import lldb
@six.add_metaclass(ABCMeta)
class ScriptedProcess:
"""
The base class for a scripted process.
Most of the base class methods are `@abstractmethod` that need to be
overwritten by the inheriting class.
DISCLAIMER: THIS INTERFACE IS STILL UNDER DEVELOPMENT AND NOT STABLE.
THE METHODS EXPOSED MIGHT CHANGE IN THE FUTURE.
"""
@abstractmethod
def __init__(self, target, args):
""" Construct a scripted process.
Args:
target (lldb.SBTarget): The target launching the scripted process.
args (lldb.SBStructuredData): A Dictionary holding arbitrary
key/value pairs used by the scripted process.
"""
self.target = None
self.args = None
if isinstance(target, lldb.SBTarget) and target.IsValid():
self.target = target
if isinstance(args, lldb.SBStructuredData) and args.IsValid():
self.args = args
@abstractmethod
def get_memory_region_containing_address(addr):
""" Get the memory region for the scripted process, containing a
specific address.
Args:
addr (int): Address to look for in the scripted process memory
regions.
Returns:
lldb.SBMemoryRegionInfo: The memory region containing the address.
None if out of bounds.
"""
pass
@abstractmethod
def get_thread_with_id(tid):
""" Get the scripted process thread with a specific ID.
Args:
tid (int): Thread ID to look for in the scripted process.
Returns:
Dict: The thread represented as a dictionary, withr the
tid thread ID. None if tid doesn't match any of the scripted
process threads.
"""
pass
@abstractmethod
def get_registers_for_thread(tid):
""" Get the register context dictionary for a certain thread of
the scripted process.
Args:
tid (int): Thread ID for the thread's register context.
Returns:
Dict: The register context represented as a dictionary, for the
tid thread. None if tid doesn't match any of the scripted
process threads.
"""
pass
@abstractmethod
def read_memory_at_address(addr, size):
""" Get a memory buffer from the scripted process at a certain address,
of a certain size.
Args:
addr (int): Address from which we should start reading.
size (int): Size of the memory to read.
Returns:
lldb.SBData: An `lldb.SBData` buffer with the target byte size and
byte order storing the memory read.
"""
pass
@abstractmethod
def get_loaded_images(self):
""" Get the list of loaded images for the scripted process.
```
class ScriptedProcessImage:
def __init__(name, file_spec, uuid, load_address):
self.name = name
self.file_spec = file_spec
self.uuid = uuid
self.load_address = load_address
```
Returns:
List[ScriptedProcessImage]: A list of `ScriptedProcessImage`
containing for each entry, the name of the library, a UUID,
an `lldb.SBFileSpec` and a load address.
None if the list is empty.
"""
pass
def get_process_id(self):
""" Get the scripted process identifier.
Returns:
int: The scripted process identifier.
"""
return 0
def launch(self):
""" Simulate the scripted process launch.
Returns:
lldb.SBError: An `lldb.SBError` with error code 0.
"""
return lldb.SBError()
def resume(self):
""" Simulate the scripted process resume.
Returns:
lldb.SBError: An `lldb.SBError` with error code 0.
"""
return lldb.SBError()
@abstractmethod
def should_stop(self):
""" Check if the scripted process plugin should produce the stop event.
Returns:
bool: True if scripted process should broadcast a stop event.
False otherwise.
"""
pass
def stop(self):
""" Trigger the scripted process stop.
Returns:
lldb.SBError: An `lldb.SBError` with error code 0.
"""
return lldb.SBError()
@abstractmethod
def is_alive(self):
""" Check if the scripted process is alive.
Returns:
bool: True if scripted process is alive. False otherwise.
"""
pass