[pypy-commit] pypy release-5.x: _rawffi bigendian issue in callbacks, callback writes narrow integer directly to MSB of 64 bit value on s390x (wrong when value is passed along)

[plan_rich]

Author: Richard Plangger <planrichi at gmail.com>
Branch: release-5.x
Changeset: r83402:3624c8c2c3be
Date: 2016-02-10 18:07 +0100
http://bitbucket.org/pypy/pypy/changeset/3624c8c2c3be/

Log:	_rawffi bigendian issue in callbacks, callback writes narrow integer
	directly to MSB of 64 bit value on s390x (wrong when value is passed
	along) (grafted from 74ebd8669f961c3ba5835f052356a9000298af98)

diff --git a/pypy/module/_rawffi/callback.py b/pypy/module/_rawffi/callback.py
--- a/pypy/module/_rawffi/callback.py
+++ b/pypy/module/_rawffi/callback.py
@@ -1,17 +1,23 @@
-
+import sys
 from pypy.interpreter.gateway import interp2app, unwrap_spec
 from pypy.interpreter.typedef import TypeDef, GetSetProperty
 from rpython.rtyper.lltypesystem import lltype, rffi
 from pypy.module._rawffi.interp_rawffi import write_ptr
 from pypy.module._rawffi.structure import W_Structure
 from pypy.module._rawffi.interp_rawffi import (W_DataInstance, letter2tp,
-     unwrap_value, unpack_argshapes, got_libffi_error)
+     unwrap_value, unpack_argshapes, got_libffi_error, is_narrow_integer_type,
+     LL_TYPEMAP, NARROW_INTEGER_TYPES)
 from rpython.rlib.clibffi import USERDATA_P, CallbackFuncPtr, FUNCFLAG_CDECL
 from rpython.rlib.clibffi import ffi_type_void, LibFFIError
 from rpython.rlib import rweakref
 from pypy.module._rawffi.tracker import tracker
 from pypy.interpreter.error import OperationError
 from pypy.interpreter import gateway
+from rpython.rlib.unroll import unrolling_iterable
+
+BIGENDIAN = sys.byteorder == 'big'
+
+unroll_narrow_integer_types = unrolling_iterable(NARROW_INTEGER_TYPES)
 
 app = gateway.applevel('''
     def tbprint(tb, err):
@@ -42,8 +48,17 @@
                 args_w[i] = space.wrap(rffi.cast(rffi.ULONG, ll_args[i]))
         w_res = space.call(w_callable, space.newtuple(args_w))
         if callback_ptr.result is not None: # don't return void
-            unwrap_value(space, write_ptr, ll_res, 0,
-                         callback_ptr.result, w_res)
+            ptr = ll_res
+            letter = callback_ptr.result
+            if BIGENDIAN:
+                # take care of narrow integers!
+                for int_type in unroll_narrow_integer_types:
+                    if int_type == letter:
+                        T = LL_TYPEMAP[int_type]
+                        n = rffi.sizeof(lltype.Signed) - rffi.sizeof(T)
+                        ptr = rffi.ptradd(ptr, n)
+                        break
+            unwrap_value(space, write_ptr, ptr, 0, letter, w_res)
     except OperationError, e:
         tbprint(space, space.wrap(e.get_traceback()),
                 space.wrap(e.errorstr(space)))
diff --git a/pypy/module/_rawffi/interp_rawffi.py b/pypy/module/_rawffi/interp_rawffi.py
--- a/pypy/module/_rawffi/interp_rawffi.py
+++ b/pypy/module/_rawffi/interp_rawffi.py
@@ -440,6 +440,10 @@
                          space.wrap("cannot directly read value"))
 wrap_value._annspecialcase_ = 'specialize:arg(1)'
 
+NARROW_INTEGER_TYPES = 'cbhiBIH?'
+
+def is_narrow_integer_type(letter):
+    return letter in NARROW_INTEGER_TYPES
 
 class W_FuncPtr(W_Root):
     def __init__(self, space, ptr, argshapes, resshape):
@@ -448,7 +452,7 @@
         self.resshape = resshape
         self.narrow_integer = False
         if resshape is not None:
-            self.narrow_integer = resshape.itemcode.lower() in ('c','h','i')
+            self.narrow_integer = is_narrow_integer_type(resshape.itemcode.lower())
 
     def getbuffer(self, space):
         return space.wrap(rffi.cast(lltype.Unsigned, self.ptr.funcsym))
@@ -512,7 +516,6 @@
                     # we get a 8 byte value in big endian
                     n = rffi.sizeof(lltype.Signed) - result.shape.size
                     result.buffer_advance(n)
-
                 return space.wrap(result)
             else:
                 self.ptr.call(args_ll, lltype.nullptr(rffi.VOIDP.TO))