Commit Graph

14 Commits

Author SHA1 Message Date
Med Ismail Bennani 7e01924e4e [lldb/Plugins] Improve error reporting with reading memory in Scripted Process
This patch improves the ScriptedPythonInterface::Dispatch method to
support passing lldb_private types to the python implementation.

This will allow, for instance, the Scripted Process python implementation
to report errors when reading memory back to lldb.

To do so, the Dispatch method will transform the private types in the
parameter pack into `PythonObject`s to be able to pass them down to the
python methods.

Then, if the call succeeded, the transformed arguments will be converted
back to their original type and re-assigned in the parameter pack, to
ensure pointers and references behaviours are preserved.

This patch also updates various scripted process python class and tests
to reflect this change.

rdar://100030995

Differential Revision: https://reviews.llvm.org/D134033

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2022-11-18 13:56:48 -08:00
Jorge Gorbe Moya d76566417e [lldb] Add matching based on Python callbacks for data formatters.
This patch adds a new matching method for data formatters, in addition
to the existing exact typename and regex-based matching. The new method
allows users to specify the name of a Python callback function that
takes a `SBType` object and decides whether the type is a match or not.

Here is an overview of the changes performed:

- Add a new `eFormatterMatchCallback` matching type, and logic to handle
  it in `TypeMatcher` and `SBTypeNameSpecifier`.

- Extend `FormattersMatchCandidate` instances with a pointer to the
  current `ScriptInterpreter` and the `TypeImpl` corresponding to the
  candidate type, so we can run registered callbacks and pass the type
  to them. All matcher search functions now receive a
  `FormattersMatchCandidate` instead of a type name.

- Add some glue code to ScriptInterpreterPython and the SWIG bindings to
  allow calling a formatter matching callback. Most of this code is
  modeled after the equivalent code for watchpoint callback functions.

- Add an API test for the new callback-based matching feature.

For more context, please check the RFC thread where this feature was
originally discussed:
https://discourse.llvm.org/t/rfc-python-callback-for-data-formatters-type-matching/64204/11

Differential Revision: https://reviews.llvm.org/D135648
2022-10-19 12:53:38 -07:00
Pavel Labath c154f397ee [lldb/python] Use PythonObject in LLDBSwigPython functions
Return our PythonObject wrappers instead of raw PyObjects (obfuscated as
void *). This ensures that ownership (reference counts) of python
objects is automatically tracked.

Differential Revision: https://reviews.llvm.org/D117462
2022-01-18 10:28:58 +01:00
Pavel Labath 7406d236d8 [lldb/python] Fix (some) dangling pointers in our glue code
This starts to fix the other half of the lifetime problems in this code
-- dangling references. SB objects created on the stack will go away
when the function returns, which is a problem if the python code they
were meant for stashes a reference to them somewhere.  Most of the time
this goes by unnoticed, as the code rarely has a reason to store these,
but in case it does, we shouldn't respond by crashing.

This patch fixes the management for a couple of SB objects (Debugger,
Frame, Thread). The SB objects are now created on the heap, and
their ownership is immediately passed on to SWIG, which will ensure they
are destroyed when the last python reference goes away. I will handle
the other objects in separate patches.

I include one test which demonstrates the lifetime issue for SBDebugger.
Strictly speaking, one should create a test case for each of these
objects and each of the contexts they are being used. That would require
figuring out how to persist (and later access) each of these objects.
Some of those may involve a lot of hoop-jumping (we can run python code
from within a frame-format string). I don't think that is
necessary/worth it since the new wrapper functions make it very hard to
get this wrong.

Differential Revision: https://reviews.llvm.org/D115925
2021-12-20 09:42:08 +01:00
Pavel Labath 82de8df26f [lldb] Clarify StructuredDataImpl ownership
StructuredDataImpl ownership semantics is unclear at best. Various
structures were holding a non-owning pointer to it, with a comment that
the object is owned somewhere else. From what I was able to gather that
"somewhere else" was the SBStructuredData object, but I am not sure that
all created object eventually made its way there. (It wouldn't matter
even if they did, as we are leaking most of our SBStructuredData
objects.)

Since StructuredDataImpl is just a collection of two (shared) pointers,
there's really no point in elaborate lifetime management, so this patch
replaces all StructuredDataImpl pointers with actual objects or
unique_ptrs to it. This makes it much easier to resolve SBStructuredData
leaks in a follow-up patch.

Differential Revision: https://reviews.llvm.org/D114791
2021-12-13 21:04:51 +01:00
Pavel Labath 9a14adeae0 [lldb] Remove 'extern "C"' from the lldb-swig-python interface
The LLDBSWIGPython functions had (at least) two problems:
- There wasn't a single source of truth (a header file) for the
  prototypes of these functions. This meant that subtle differences
  in copies of function declarations could go by undetected. And
  not-so-subtle differences would result in strange runtime failures.
- All of the declarations had to have an extern "C" interface, because
  the function definitions were being placed inside and extert "C" block
  generated by swig.

This patch fixes both problems by moving the function definitions to the
%header block of the swig files. This block is not surrounded by extern
"C", and seems more appropriate anyway, as swig docs say it is meant for
"user-defined support code" (whereas the previous %wrapper code was for
automatically-generated wrappers).

It also puts the declarations into the SWIGPythonBridge header file
(which seems to have been created for this purpose), and ensures it is
included by all code wishing to define or use these functions. This
means that any differences in the declaration become a compiler error
instead of a runtime failure.

Differential Revision: https://reviews.llvm.org/D114369
2021-11-30 11:06:09 +01:00
Med Ismail Bennani 738621d047 [lldb/bindings] Change ScriptedThread initializer parameters
This patch changes the `ScriptedThread` initializer in couple of ways:
- It replaces the `SBTarget` parameter by a `SBProcess` (pointing to the
  `ScriptedProcess` that "owns" the `ScriptedThread`).
- It adds a reference to the `ScriptedProcessInfo` Dictionary, to pass
  arbitrary user-input to the `ScriptedThread`.

This patch also fixes the SWIG bindings methods that call the
`ScriptedProcess` and `ScriptedThread` initializers by passing all the
arguments to the appropriate `PythonCallable` object.

Differential Revision: https://reviews.llvm.org/D112046

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-11-10 17:43:28 +01:00
Med Ismail Bennani a758c9f720 [lldb/Plugins] Add memory region support in ScriptedProcess
This patch adds support for memory regions in Scripted Processes.
This is necessary to read the stack memory region in order to
reconstruct each stackframe of the program.

In order to do so, this patch makes some changes to the SBAPI, namely:
- Add a new constructor for `SBMemoryRegionInfo` that takes arguments
  such as the memory region name, address range, permissions ...
  This is used when reading memory at some address to compute the offset
  in the binary blob provided by the user.
- Add a `GetMemoryRegionContainingAddress` method to `SBMemoryRegionInfoList`
  to simplify the access to a specific memory region.

With these changes, lldb is now able to unwind the stack and reconstruct
each frame. On top of that, reloading the target module at offset 0 allows
lldb to symbolicate the `ScriptedProcess` using debug info, similarly to an
ordinary Process.

To test this, I wrote a simple program with multiple function calls, ran it in
lldb, stopped at a leaf function and read the registers values and copied
the stack memory into a binary file. These are then used in the python script.

Differential Revision: https://reviews.llvm.org/D108953

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-10-08 14:54:07 +02:00
Med Ismail Bennani 59d8dd79e1 [lldb/Plugins] Add support for ScriptedThread in ScriptedProcess
This patch introduces the `ScriptedThread` class with its python
interface.

When used with `ScriptedProcess`, `ScriptedThreaad` can provide various
information such as the thread state, stop reason or even its register
context.

This can be used to reconstruct the program stack frames using lldb's unwinder.

rdar://74503836

Differential Revision: https://reviews.llvm.org/D107585

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-10-08 14:54:07 +02:00
Shafik Yaghmour ec00502b9f [NFC][LLDB] Removing extra semicolons to silence -Wc++98-compat-extra-semi diagnostics 2021-03-23 14:32:36 -07:00
Med Ismail Bennani 1f6a57c1a0 [lldb/Interpreter] Add ScriptInterpreter Wrapper for ScriptedProcess
This patch adds a ScriptedProcess interface to the ScriptInterpreter and
more specifically, to the ScriptInterpreterPython.

This interface will be used in the C++ `ScriptProcess` Process Plugin to
call the script methods.

At the moment, not all methods are implemented, they will upstreamed in
upcoming patches.

This patch also adds helper methods to the ScriptInterpreter to
convert `SBAPI` Types (SBData & SBError) to `lldb_private` types
(DataExtractor & Status).

rdar://65508855

Differential Revision: https://reviews.llvm.org/D95711

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-23 18:24:47 +01:00
Med Ismail Bennani 36254f1a0f
[lldb] Revert ScriptedProcess patches
This patch reverts the following commits:
- 5a9c34918b
- 46796762af
- 2cff3dec11
- 182f0d1a34
- d62a53aaf1

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-01 23:23:27 +00:00
Med Ismail Bennani 5a9c34918b [lldb/Plugins] Fix SWIGPythonBridge build issue
This patch should fi the build issue on the windows bots:
https://lab.llvm.org/buildbot/#/builders/83/builds/4214/steps/5/logs/stdio

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-01 22:37:36 +01:00
Med Ismail Bennani 182f0d1a34 [lldb/Interpreter] Add ScriptInterpreter Wrapper for ScriptedProcess
This patch adds a ScriptedProcess interface to the ScriptInterpreter and
more specifically, to the ScriptInterpreterPython.

This interface will be used in the C++ `ScriptProcess` Process Plugin to
call the script methods.

At the moment, not all methods are implemented, they will upstreamed in
upcoming patches.

This patch also adds helper methods to the ScriptInterpreter to
convert `SBAPI` Types (SBData & SBError) to `lldb_private` types
(DataExtractor & Status).

rdar://65508855

Differential Revision: https://reviews.llvm.org/D95711

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-01 21:13:31 +01:00