[Rpm-maint] [PATCH] fix the signatures of the METH_NOARGS callbacks

[Ales Kozumplik]

Hello,

thank you for the patches. I've reviewed them and will push them as soon 
as the repos start working again.

Ales

On 12/23/2011 12:59 AM, David Malcolm wrote:
> Various Python method callbacks have signatures of the form:
>
>    static PyObject *
>    foo(some_object_subclass *obj)
>
> and are registered within the PyMethodDef tables with the METH_NOARGS
> flag [1], with a cast to (PyCFunction) due to the PyObject/subclass
> mismatch.
>
> However, such callbacks do receive two arguments: they are invoked with
> a signature of this form:
>
>    static PyObject *
>    foo(some_object_subclass *obj, PyObject *ignored)
>
> The CPython interpreter only uses METH_NOARGS to allow it to pass NULL as the
> second parameter: there are still two parameters.  The dispatch code is in
> Python's Python/ceval.c:call_function:
>
>              if (flags&  METH_NOARGS&&  na == 0) {
>                  C_TRACE(x, (*meth)(self,NULL));
>              }
>
> The fact that this has ever worked may be a coincidence of the
> platform/compiler's calling conventions, and I don't think it's guaranteed to
> keep working.
>
> Found using my static analysis tool:
> http://gcc-python-plugin.readthedocs.org/en/latest/cpychecker.html#verification-of-pymethoddef-tables
>
>
> [1] http://docs.python.org/c-api/structures.html#METH_NOARGS
> ---
>   python/rpmfi-py.c |   42 +++++++++++++++++++++---------------------
>   python/rpmmi-py.c |    4 ++--
>   python/rpmte-py.c |   34 +++++++++++++++++-----------------
>   3 files changed, 40 insertions(+), 40 deletions(-)
>
> diff --git a/python/rpmfi-py.c b/python/rpmfi-py.c
> index a43fee3..4bfcc81 100644
> --- a/python/rpmfi-py.c
> +++ b/python/rpmfi-py.c
> @@ -14,74 +14,74 @@ struct rpmfiObject_s {
>   };
>
>   static PyObject *
> -rpmfi_FC(rpmfiObject * s)
> +rpmfi_FC(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFC(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FX(rpmfiObject * s)
> +rpmfi_FX(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFX(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_DC(rpmfiObject * s)
> +rpmfi_DC(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiDC(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_DX(rpmfiObject * s)
> +rpmfi_DX(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiDX(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_BN(rpmfiObject * s)
> +rpmfi_BN(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmfiBN(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_DN(rpmfiObject * s)
> +rpmfi_DN(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmfiDN(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FN(rpmfiObject * s)
> +rpmfi_FN(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmfiFN(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FFlags(rpmfiObject * s)
> +rpmfi_FFlags(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFFlags(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_VFlags(rpmfiObject * s)
> +rpmfi_VFlags(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiVFlags(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FMode(rpmfiObject * s)
> +rpmfi_FMode(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFMode(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FState(rpmfiObject * s)
> +rpmfi_FState(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFState(s->fi));
>   }
>
>   /* XXX rpmfiFDigest */
>   static PyObject *
> -rpmfi_Digest(rpmfiObject * s)
> +rpmfi_Digest(rpmfiObject * s, PyObject * unused)
>   {
>       char *digest = rpmfiFDigestHex(s->fi, NULL);
>       if (digest) {
> @@ -94,49 +94,49 @@ rpmfi_Digest(rpmfiObject * s)
>   }
>
>   static PyObject *
> -rpmfi_FLink(rpmfiObject * s)
> +rpmfi_FLink(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmfiFLink(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FSize(rpmfiObject * s)
> +rpmfi_FSize(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("L", rpmfiFSize(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FRdev(rpmfiObject * s)
> +rpmfi_FRdev(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFRdev(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FMtime(rpmfiObject * s)
> +rpmfi_FMtime(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFMtime(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FUser(rpmfiObject * s)
> +rpmfi_FUser(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmfiFUser(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FGroup(rpmfiObject * s)
> +rpmfi_FGroup(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmfiFGroup(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FColor(rpmfiObject * s)
> +rpmfi_FColor(rpmfiObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmfiFColor(s->fi));
>   }
>
>   static PyObject *
> -rpmfi_FClass(rpmfiObject * s)
> +rpmfi_FClass(rpmfiObject * s, PyObject * unused)
>   {
>       const char * FClass;
>
> @@ -196,7 +196,7 @@ rpmfi_iternext(rpmfiObject * s)
>   	    PyTuple_SET_ITEM(result, 11, Py_None);
>   	} else
>   	    PyTuple_SET_ITEM(result, 11, Py_BuildValue("s", FGroup));
> -	PyTuple_SET_ITEM(result, 12, rpmfi_Digest(s));
> +	PyTuple_SET_ITEM(result, 12, rpmfi_Digest(s, NULL));
>
>       } else
>   	s->active = 0;
> diff --git a/python/rpmmi-py.c b/python/rpmmi-py.c
> index 977e475..8e670ce 100644
> --- a/python/rpmmi-py.c
> +++ b/python/rpmmi-py.c
> @@ -78,7 +78,7 @@ rpmmi_iternext(rpmmiObject * s)
>   }
>
>   static PyObject *
> -rpmmi_Instance(rpmmiObject * s)
> +rpmmi_Instance(rpmmiObject * s, PyObject * unused)
>   {
>       int rc = 0;
>
> @@ -89,7 +89,7 @@ rpmmi_Instance(rpmmiObject * s)
>   }
>
>   static PyObject *
> -rpmmi_Count(rpmmiObject * s)
> +rpmmi_Count(rpmmiObject * s, PyObject * unused)
>   {
>       DEPRECATED_METHOD("use len(mi) instead");
>       return Py_BuildValue("i", PyMapping_Size((PyObject *)s));
> diff --git a/python/rpmte-py.c b/python/rpmte-py.c
> index 73006e3..0850fc4 100644
> --- a/python/rpmte-py.c
> +++ b/python/rpmte-py.c
> @@ -46,83 +46,83 @@ struct rpmteObject_s {
>   };
>
>   static PyObject *
> -rpmte_TEType(rpmteObject * s)
> +rpmte_TEType(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmteType(s->te));
>   }
>
>   static PyObject *
> -rpmte_N(rpmteObject * s)
> +rpmte_N(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteN(s->te));
>   }
>
>   static PyObject *
> -rpmte_E(rpmteObject * s)
> +rpmte_E(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteE(s->te));
>   }
>
>   static PyObject *
> -rpmte_V(rpmteObject * s)
> +rpmte_V(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteV(s->te));
>   }
>
>   static PyObject *
> -rpmte_R(rpmteObject * s)
> +rpmte_R(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteR(s->te));
>   }
>
>   static PyObject *
> -rpmte_A(rpmteObject * s)
> +rpmte_A(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteA(s->te));
>   }
>
>   static PyObject *
> -rpmte_O(rpmteObject * s)
> +rpmte_O(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteO(s->te));
>   }
>
>   static PyObject *
> -rpmte_NEVR(rpmteObject * s)
> +rpmte_NEVR(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteNEVR(s->te));
>   }
>
>   static PyObject *
> -rpmte_NEVRA(rpmteObject * s)
> +rpmte_NEVRA(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("s", rpmteNEVRA(s->te));
>   }
>
>   static PyObject *
> -rpmte_Color(rpmteObject * s)
> +rpmte_Color(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmteColor(s->te));
>   }
>
>   static PyObject *
> -rpmte_PkgFileSize(rpmteObject * s)
> +rpmte_PkgFileSize(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("L", rpmtePkgFileSize(s->te));
>   }
>
>   static PyObject *
> -rpmte_Parent(rpmteObject * s)
> +rpmte_Parent(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmteParent(s->te));
>   }
>
> -static PyObject * rpmte_Failed(rpmteObject * s)
> +static PyObject * rpmte_Failed(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmteFailed(s->te));
>   }
>
> -static PyObject * rpmte_Problems(rpmteObject * s)
> +static PyObject * rpmte_Problems(rpmteObject * s, PyObject * unused)
>   {
>       rpmps ps = rpmteProblems(s->te);
>       PyObject *problems = rpmps_AsList(ps);
> @@ -132,20 +132,20 @@ static PyObject * rpmte_Problems(rpmteObject * s)
>
>   /*
>   static PyObject *
> -rpmte_DependsOnKey(rpmteObject * s)
> +rpmte_DependsOnKey(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmteDependsOnKey(s->te));
>   }
>   */
>
>   static PyObject *
> -rpmte_DBOffset(rpmteObject * s)
> +rpmte_DBOffset(rpmteObject * s, PyObject * unused)
>   {
>       return Py_BuildValue("i", rpmteDBOffset(s->te));
>   }
>
>   static PyObject *
> -rpmte_Key(rpmteObject * s)
> +rpmte_Key(rpmteObject * s, PyObject * unused)
>   {
>       PyObject * Key;
>