Also fixes li_std_vector_enum testcase when run with -threads.
Patch supplied on swig-devel mailing list on 12 Sep with details...
==============================================
I just wanted to mention that I found a crash issue in bug..
I am using SWIG 2.0.11 with python and have –threads enabled. I have a C++ std::vector that I instantiate in SWIG with %template. I also have a method in a class that returns this vector. I also include std_vector.i, btw..
When I iterate like so:
children = Action.getActionList()
for child in children:
pass
Everything is fine..
When I iterate like this:
for child in Action.getActionList()
pass
Product crashes.
The problem is the following. This code gets called first:
SWIGINTERN PyObject *_wrap_delete_SwigPyIterator(PyObject *SWIGUNUSEDPARM(self), PyObject *args) {
PyObject *resultobj = 0;
swig::SwigPyIterator *arg1 = (swig::SwigPyIterator *) 0 ;
void *argp1 = 0 ;
int res1 = 0 ;
PyObject * obj0 = 0 ;
if(!PyArg_UnpackTuple(args,(char *)"delete_SwigPyIterator",1,1,&obj0)) SWIG_fail;
res1 = SWIG_ConvertPtr(obj0, &argp1,SWIGTYPE_p_swig__SwigPyIterator, SWIG_POINTER_DISOWN | 0 );
if (!SWIG_IsOK(res1)) {
SWIG_exception_fail(SWIG_ArgError(res1), "in method '" "delete_SwigPyIterator" "', argument " "1"" of type '" "swig::SwigPyIterator *""'");
}
arg1 = reinterpret_cast< swig::SwigPyIterator * >(argp1);
{
SWIG_PYTHON_THREAD_BEGIN_ALLOW;
delete arg1;
SWIG_PYTHON_THREAD_END_ALLOW;
}
resultobj = SWIG_Py_Void();
return resultobj;
fail:
return NULL;
}
Note the SWIG_PYTHON_THREAD_BEGIN_ALLOW/END_ALLOW. In between those two statements, we delete arg1. That in turn will eventually end up in this code:
namespace swig {
class SwigPtr_PyObject {
protected:
PyObject *_obj;
public:
… snip! …
~SwigPtr_PyObject()
{
Py_XDECREF(_obj);
}
Uh-oh! We call Py_XDECREF when we aren’t supposed to because we are in a SWIG_PYTHON_THREAD_BEGIN_ALLOW/END_ALLOW section!
This takes care of the issue:
namespace swig {
class SwigPtr_PyObject {
protected:
PyObject *_obj;
public:
… snip! …
~SwigPtr_PyObject()
{
SWIG_PYTHON_THREAD_BEGIN_BLOCK;
Py_XDECREF(_obj);
SWIG_PYTHON_THREAD_END_BLOCK;
}
There are several other methods in this class that use the Python API, but don’t have the BEGIN/END block defined. I’m not sure if they are required for all of them, but I believe they are..
I have attached a modified pyclasses.swg with what I believe are the correct changes. This code is from 2.0.11, but as far as I can tell, it’s the same as what is in 3.0.2…
Apologies for not doing more here (making/running tests, getting it in the code repository, etc..), but I’m under some pressure to get some unrelated things done…
- Examples/Makefile.in rules use SRCDIR as the relative source directory
- ./config.status replicates Examples/ source directory tree in build
directory, and copies each Makefile to build directory, prefixed with
a header which sets SRCDIR to source directory
- Examples/test-suite/.../Makefile.in set SRCDIR from Autoconf-set srcdir
- Examples/test-suite/errors/Makefile.in needs to filter out source
directory from SWIG error messages
- Lua: embedded interpreters are passed location of run-time test
- Python: copy run-time scripts to build directory because of 2to3
conversion; import_packages example copies __init__.py from source
directory; test-suite sets SCRIPTDIR to location of run-time tests
- Javascript: binding.gyp renamed to binding.gyp.in so that $srcdir
can be substituted with SRCDIR; removed './' from require() statements
so that NODE_PATH can be used to point Node.js to build directory
- some of the %.clean rules in the test-suite Makefiles were using a single tab
as an empty rule, dangerous! I've replaced these with the safer '@exit 0'.
It was previously possible to assign "hello" to a variable backed by char[5]
storage in C, and the array contained the correct character data but without
the trailing NUL, which was unexpected in C.
This is not allowed any more, only "helo" can fit into a char[5] now and
anything else fails the type check, just as it already happened for the longer
strings before.
Closes#122
Use the usual C rule for NUL-terminated strings instead of discarding all the
trailing NUL characters.
This was unexpected (as buffers in C code are not necessarily always padded
with NULs to their full length) and also inconsistent among languages as this
was only done for those of them using typemaps/strings.swg but not for C# or
Java, for example, which terminated the string at the first NUL even before
this change.
Notice that this patch couldn't use strlen() or wcslen() with possibly not
NUL-terminated strings, so we had to add [our own equivalents of] strnlen()
and wcsnlen() and use them instead. This required adding yet another parameter
to string typemap macros, so update the example using them accordingly too.
These typemaps are currently defined for C#, Java and Python only and the
tests are provided only for these languages.
Also add a brief description of the new header to the documentation.
Allow using Perl-like \l, \L, \u, \U and \E escape sequences in the
substitution string used with %rename("%(regex:/pattern/subst/)s").
This is useful for e.g. title casing all string after removing some prefix.
Closes#82
This fix makes the handling of type 'float' and 'double' the same. The implementation requires the
C99 isfinite() macro, or otherwise some platform dependent equivalents, to be available.
SF bug #1327
This doesn't have any noticeable effect with the usage of
SWIG_AsWCharPtrAndSize as shipped by SWIG, but could be a problem if a
user is using this function with cptr equal to zero and psize is non-zero
- the length would be incorrectly set due to the call to PyUnicode_GetSize
failing.
