Commit Graph

18 Commits

Author SHA1 Message Date
Enrico Granata
b1cf558d83 Fix an issue where pressing CTRL+C in the interactive script interpreter causes LLDB to crash
This is because PyThreadState_Get() assumes a non-NULL thread state and crashes otherwise; but PyThreadState_GET is just a shortcut (in non-Python-debugging builds) for the global variable that holds the thread state

The behavior of CTRL+C is slightly more erratic than one would like. CTRL+C in the middle of execution of Python code will cause that execution to be interrupted (e.g. time.sleep(1000)), but a CTRL+C at the prompt will just cause a KeyboardInterrupt and not exit the interpreter - worse, it will only trigger the exception once one presses ENTER.

None of this is optimal, of course, but I don't have a lot of time to appease the Python deities with the proper spells right now, and fixing the crasher is already a good thing in and of itself

llvm-svn: 260199
2016-02-09 05:46:47 +00:00
Aidan Dodds
bdc52ef38b Fix const cast error for MSVC2015 build.
The Visual Studio 2015 build was failing with the following error:
error C2440: 'initializing': cannot convert from 'const char [12]' to 'char *'

This should fix the problem by initializing a non const char array, instead of taking a pointer to const static data.

llvm-svn: 259042
2016-01-28 13:05:21 +00:00
Zachary Turner
7a76845c48 Fix Python 3 issues related to OS plugins.
* lldb::tid_t was being converted incorrectly, so this is updated to use
PythonInteger instead of manual Python Native API calls.
* OSPlugin_RegisterContextData was assuming that the result of
  get_register_data was a string, when in fact it is a bytes.  So this
  method is updated to use PythonBytes to do the work.

llvm-svn: 257398
2016-01-11 22:16:17 +00:00
Zachary Turner
7d2d09842a Python 3 - Fix script import --allow-reload.
Differential Revision: http://reviews.llvm.org/D15209
Reviewed By: Todd Fiala

llvm-svn: 254791
2015-12-04 22:59:14 +00:00
Zachary Turner
3946247caf Introduce a PythonExceptionState class.
This is a helper class which supports a number of
features including exception to string formatting with
backtrace handling and auto-restore of exception state
upon scope exit.

Additionally, unit tests are included to verify the
feature set of the class.

llvm-svn: 252994
2015-11-13 01:24:52 +00:00
Siva Chandra
9ac7a6c51f [SBValue] Add a method GetNumChildren(uint32_t max)
Summary:
Along with this, support for an optional argument to the "num_children"
method of a Python synthetic child provider has also been added. These have
been added with the following use case in mind:

Synthetic child providers currently have a method "has_children" and
"num_children". While the former is good enough to know if there are
children, it does not give any insight into how many children there are.
Though the latter serves this purpose, calculating the number for children
of a data structure could be an O(N) operation if the data structure has N
children. The new method added in this change provide a middle ground.
One can call GetNumChildren(K) to know if a child exists at an index K
which can be as large as the callers tolerance can be. If the caller wants
to know about children beyond K, it can make an other call with 2K. If the
synthetic child provider maintains state about it counting till K
previosly, then the next call is only an O(K) operation. Infact, all
calls made progressively with steps of K will be O(K) operations.

Reviewers: vharron, clayborg, granata.enrico

Subscribers: labath, lldb-commits

Differential Revision: http://reviews.llvm.org/D13778

llvm-svn: 250930
2015-10-21 19:28:08 +00:00
Zachary Turner
32064024b9 Fix potential file i/o problem with python handles.
llvm-svn: 250838
2015-10-20 17:38:49 +00:00
Zachary Turner
9c40264fda Introduce a PythonFile object, and use it everywhere.
Python file handling got an overhaul in Python 3, and it affects
the way we have to interact with files.  Notably:

1) `PyFile_FromFile` no longer exists, and instead we have to use
   `PyFile_FromFd`.  This means having a way to get an fd from
   a FILE*.  For this we reuse the lldb_private::File class to
   convert between FILE*s and fds, since there are some subtleties
   regarding ownership rules when FILE*s and fds refer to the same
   file.
2) PyFile is no longer a builtin type, so there is no such thing as
   `PyFile_Check`.  Instead, files in Python 3 are just instances
   of `io.IOBase`.  So the logic for checking if something is a file
   in Python 3 is to check if it is a subclass of that module.

Additionally, some unit tests are added to verify that `PythonFile`
works as expected on Python 2 and Python 3, and
`ScriptInterpreterPython` is updated to use `PythonFile` instead of
manual calls to the various `PyFile_XXX` methods.

llvm-svn: 250444
2015-10-15 19:35:48 +00:00
Zachary Turner
4eff2d3177 Make uses of /dev/null portable across OSes.
Most platforms have "/dev/null".  Windows has "nul".  Instead of
hardcoding the string /dev/null at various places, make a constant
that contains the correct value depending on the platform, and use
that everywhere instead.

llvm-svn: 250331
2015-10-14 21:37:36 +00:00
Stephane Sezer
7686644691 Avoid a -Wreorder warning in ScriptInterpreterPython.cpp.
llvm-svn: 250322
2015-10-14 20:39:41 +00:00
Zachary Turner
079fe48a1d Fix Python initialization for Python 3.
Python 3 reverses the order in which you must call Py_InitializeEx
and PyEval_InitThreads.  Since that log is in itself already a
little nuanced, it is refactored into a function so that the reversal
is more clear.  At the same time, there's a lot of logic during
Python initialization to save off a bunch of state and then restore
it after initialization is complete.  To express this more cleanly,
it is refactored to an RAII-style pattern where state is saved off
on acquisition and restored on release.

llvm-svn: 250306
2015-10-14 17:51:29 +00:00
Zachary Turner
60c24f70fe Change swig interface files to use PythonDataObjects.
llvm-svn: 250303
2015-10-14 16:59:32 +00:00
Pavel Labath
cb57fdd98d Fix compiler warnings in ScriptInterpreterPython
llvm-svn: 250282
2015-10-14 09:18:23 +00:00
Zachary Turner
02545feb2e Change PyFile_FromFile to use PyFile_FromFd when using Py3.
llvm-svn: 250213
2015-10-13 19:32:53 +00:00
Zachary Turner
f8b22f8fea Fix ref counting of Python objects.
PythonObjects were being incorrectly ref-counted. This problem was
pervasive throughout the codebase, leading to an unknown number of memory
leaks and potentially use-after-free.

The issue stems from the fact that Python native methods can either return
"borrowed" references or "owned" references. For the former category, you
*must* incref it prior to decrefing it. And for the latter category, you
should not incref it before decrefing it. This is mostly an issue when a
Python C API method returns a `PyObject` to you, but it can also happen with
a method accepts a `PyObject`. Notably, this happens in `PyList_SetItem`,
which is documented to "steal" the reference that you give it. So if you
pass something to `PyList_SetItem`, you cannot hold onto it unless you
incref it first. But since this is one of only two exceptions in the
entire API, it's confusing and difficult to remember.

Our `PythonObject` class was indiscriminantely increfing every object it
received, which means that if you passed it an owned reference, you now
have a dangling reference since owned references should not be increfed.
We were doing this in quite a few places.

There was also a fair amount of manual increfing and decrefing prevalent
throughout the codebase, which is easy to get wrong.

This patch solves the problem by making any construction of a
`PythonObject` from a `PyObject` take a flag which indicates whether it is
an owned reference or a borrowed reference. There is no way to construct a
`PythonObject` without this flag, and it does not offer a default value,
forcing the user to make an explicit decision every time.

All manual uses of `PyObject` have been cleaned up throughout the codebase
and replaced with `PythonObject` in order to make RAII the predominant
pattern when dealing with native Python objects.

Differential Revision: http://reviews.llvm.org/D13617
Reviewed By: Greg Clayton

llvm-svn: 250195
2015-10-13 18:16:15 +00:00
Zachary Turner
638b98d3ed Fix build broken by r249885
llvm-svn: 249900
2015-10-09 20:56:23 +00:00
Zachary Turner
22c8efcd34 Port native Python-API to 3.x
With this change, liblldb is 95% of the way towards being able
to work under both Python 2.x and Python 3.x.  This should
introduce no functional change for Python 2.x, but for Python
3.x there are some important changes.  Primarily, these are:

1) PyString doesn't exist in Python 3.  Everything is a PyUnicode.
   To account for this, PythonString now stores a PyBytes instead
   of a PyString.  In Python 2, this is equivalent to a PyUnicode,
   and in Python 3, we do a conversion from PyUnicode to PyBytes
   and store the PyBytes.
2) PyInt doesn't exist in Python 3.  Everything is a PyLong.  To
   account for this, PythonInteger stores a PyLong instead of a
   PyInt.  In Python 2.x, this requires doing a conversion to
   PyLong when creating a PythonInteger from a PyInt.  In 3.x,
   there is no PyInt anyway, so we can assume everything is a
   PyLong.
3) PyFile_FromFile doesn't exist in Python 3.  Instead there is a
   PyFile_FromFd.  This is not addressed in this patch because it
   will require quite a large change to plumb fd's all the way
   through the system into the ScriptInterpreter.  This is the only
   remaining piece of the puzzle to get LLDB supporting Python 3.x.

Being able to run the test suite is not addressed in this patch.
After the extension module can compile and you can enter an embedded
3.x interpreter, the test suite will be addressed in a followup.

llvm-svn: 249886
2015-10-09 19:45:41 +00:00
Zachary Turner
2c1f46dcc6 Convert the ScriptInterpreter system to a plugin-based one.
Previously embedded interpreters were handled as ad-hoc source
files compiled into source/Interpreter.  This made it hard to
disable a specific interpreter, or to add support for other
interpreters and allow the developer to choose which interpreter(s)
were enabled for a particular build.

This patch converts script interpreters over to a plugin-based system.
Script interpreters now live in source/Plugins/ScriptInterpreter, and
the canonical LLDB interpreter, ScriptInterpreterPython, is moved there
as well.

Any new code interfacing with the Python C API must live in this location
from here on out.  Additionally, generic code should never need to
reference or make assumptions about the presence of a specific interpreter
going forward.

Differential Revision: http://reviews.llvm.org/D11431
Reviewed By: Greg Clayton

llvm-svn: 243681
2015-07-30 20:28:07 +00:00