23 Commits

Author SHA1 Message Date
Pavel Labath
ebb6bb725e [lldb/python] Plug SBStructuredData leaks
This applies the from D114259 to the SBStructuredData class.
2021-12-14 17:02:24 +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
Pavel Labath
7f09ab08de [lldb] Fix [some] leaks in python bindings
Using an lldb_private object in the bindings involves three steps
- wrapping the object in it's lldb::SB variant
- using swig to convert/wrap that to a PyObject
- wrapping *that* in a lldb_private::python::PythonObject

Our SBTypeToSWIGWrapper was only handling the middle part. This doesn't
just result in increased boilerplate in the callers, but is also a
functionality problem, as it's very hard to get the lifetime of of all
of these objects right. Most of the callers are creating the SB object
(step 1) on the stack, which means that we end up with dangling python
objects after the function terminates. Most of the time this isn't a
problem, because the python code does not need to persist the objects.
However, there are legitimate cases where they can do it (and even if
the use case is not completely legitimate, crashing is not the best
response to that).

For this reason, some of our code creates the SB object on the heap, but
it has another problem -- it never gets cleaned up.

This patch begins to add a new function (ToSWIGWrapper), which does all
of the three steps, while properly taking care of ownership. In the
first step, I have converted most of the leaky code (except for
SBStructuredData, which needs a bit more work).

Differential Revision: https://reviews.llvm.org/D114259
2021-11-22 15:14:52 +01:00
Pavel Labath
f1127914d3 [lldb] Deobfuscate python-swigsafecast.swig
This file was way more complicated than it needed to be.

This patch removes the automagic reference-to-pointer delegation and
replaces the template specializations with regular free functions
(taking reference arguments).

The reason I chose references is twofold:
- there are more arguments being passed by reference than by pointer
- the reference arguments make it more obvious that there is a lot of
  leaking going on in there.

Currently, the code was assuming that the pointer arguments have some
kind of a special meaning and that pointer functions take ownership of
their arguments, which isn't true (it's possible it was true at some
point in the past, I haven't done the archeology).

This makes it easier to implement proper lifetime management in
follow-up patches.

Differential Revision: https://reviews.llvm.org/D114150
2021-11-18 19:27:09 +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
Med Ismail Bennani
3925204c1f [lldb/Plugins] Introduce Scripted Interface Factory
This patch splits the previous `ScriptedProcessPythonInterface` into
multiple specific classes:

1. The `ScriptedInterface` abstract class that carries the interface
   instance object and its virtual pure abstract creation method.

2. The `ScriptedPythonInterface` that holds a generic `Dispatch` method that
   can be used by various interfaces to call python methods and also keeps a
   reference to the Python Script Interpreter instance.

3. The `ScriptedProcessInterface` that describes the base Scripted
   Process model with all the methods used in the underlying script.

All these components are used to refactor the `ScriptedProcessPythonInterface`
class, making it more modular.

This patch is also a requirement for the upcoming work on `ScriptedThread`.

Differential Revision: https://reviews.llvm.org/D107521

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-09-03 19:37:25 +02:00
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
Dave Lee
daf3699869 [lldb] Ignore linkage diagnostic for LLDBSwigPythonBreakpointCallbackFunction (NFC)
Ignore `-Wreturn-type-c-linkage` diagnostics for `LLDBSwigPythonBreakpointCallbackFunction`.

The function is defined in `python-wrapper.swig` which uses `extern "C" { ... }` blocks.
The declaration of this function in `ScriptInterpreterPython.cpp` already uses these
same pragmas to silence the warning there.

This prevents `-Werror` builds from failing.

Differential Revision: https://reviews.llvm.org/D98368
2021-03-10 14:15:54 -08:00
Med Ismail Bennani
36254f1a0f
[lldb] Revert ScriptedProcess patches
This patch reverts the following commits:
- 5a9c34918bb1526b7e8c29aa5e4fb8d8e27e27b4
- 46796762afe76496ec4dd900f64d0cf4cdc30e99
- 2cff3dec1171188ce04ab1a4373cc1885ab97be1
- 182f0d1a34419445bb19d67581d6ac1afc98b7fa
- d62a53aaf1d38a55d1affbd3a30d564a4e9d3171

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-03-01 23:23:27 +00:00
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
Richard Smith
2f95c50a8b Fix use of wrong printf format specifier for size_t argument.
This causes a build break under -Werror=format.
2020-09-29 16:02:08 -07:00
Jim Ingham
1b1d981598 Revert "Revert "Add the ability to write target stop-hooks using the ScriptInterpreter.""
This reverts commit f775fe59640a2e837ad059a8f40e26989d4f9831.

I fixed a return type error in the original patch that was causing a test failure.
Also added a REQUIRES: python to the shell test so we'll skip this for
people who build lldb w/o Python.
Also added another test for the error printing.
2020-09-29 12:01:14 -07:00
Jonas Devlieghere
f775fe5964 Revert "Add the ability to write target stop-hooks using the ScriptInterpreter."
This temporarily reverts commit b65966cff65bfb66de59621347ffd97238d3f645
while Jim figures out why the test is failing on the bots.
2020-09-28 09:04:32 -07:00
Fangrui Song
67782a0f99 [lldb/bindings] Fix -Wformat after D88123 2020-09-25 17:33:12 -07:00
Jim Ingham
b65966cff6 Add the ability to write target stop-hooks using the ScriptInterpreter.
Differential Revision: https://reviews.llvm.org/D88123
2020-09-25 15:44:55 -07:00
Jonas Devlieghere
b79dff0279 [lldb] Make sure we don't leak SBThreadPlan pointer (NFCI)
Make sure we don't accidentally leak the SBThreadPlan pointer when we
return before handing it off to Python to manage its lifetime.
2020-07-20 16:58:06 -07:00
Lawrence D'Anna
52712d3ff7 Re-land "get rid of PythonInteger::GetInteger()"
This was reverted due to a python2-specific bug.  Re-landing with a fix
for python2.

Summary:
One small step in my long running quest to improve python exception handling in
LLDB.  Replace GetInteger() which just returns an int with As<long long> and
friends, which return Expected types that can track python exceptions

Reviewers: labath, jasonmolenda, JDevlieghere, vadimcn, omjavaid

Reviewed By: labath, omjavaid

Subscribers: omjavaid, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D78462
2020-05-08 10:57:10 -07:00
Muhammad Omair Javaid
478619cf9a Revert "get rid of PythonInteger::GetInteger()"
This reverts commit 7375212172951d2fc283c81d03c1a8588c3280c6.

This causes multiple test failures on LLDB AArch64 Linux buildbot.
http://lab.llvm.org:8011/builders/lldb-aarch64-ubuntu/builds/3695

Differential Revision: https://reviews.llvm.org/D78462
2020-04-23 04:38:32 +05:00
Lawrence D'Anna
7375212172 get rid of PythonInteger::GetInteger()
Summary:
One small step in my long running quest to improve python exception handling in
LLDB.  Replace GetInteger() which just returns an int with As<long long> and
friends, which return Expected types that can track python exceptions

Reviewers: labath, jasonmolenda, JDevlieghere, vadimcn

Reviewed By: labath

Subscribers: lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D78462
2020-04-21 16:55:51 -07:00
Jonas Devlieghere
6498aff249 [lldb/Bindings] Move bindings into their own subdirectory
All the code required to generate the language bindings for Python and
Lua lives under scripts, even though the majority of this code aren't
scripts at all, and surrounded by scripts that are totally unrelated.

I've reorganized these files and moved everything related to the
language bindings into a new top-level directory named bindings. This
makes the corresponding files self contained and much more discoverable.

Differential revision: https://reviews.llvm.org/D72437
2020-01-09 08:44:34 -08:00