Include <malloc.h> on windows, to avoid warnings when compiling with mingw.

Don't use SEH when compiling wth mingw.
Use IS_INTRESOURCE to determine function name from function ordinal.

Rewrite the code that allocates and frees callback functions, hopefully
this avoids the coverty warnings: Remove the THUNK typedef, and move the
definition of struct ffi_info into the header file.

Modules/_ctypes/_ctypes.c

@@ -105,6 +105,10 @@ bytes(cdata)
 #include <ffi.h>
 #ifdef MS_WIN32
 #include <windows.h>
+#include <malloc.h>
+#ifndef IS_INTRESOURCE
+#define IS_INTRESOURCE(x) (((size_t)(x) >> 16) == 0)
+#endif
 # ifdef _WIN32_WCE
 /* Unlike desktop Windows, WinCE has both W and A variants of
    GetProcAddress, but the default W version is not what we want */
@@ -2402,7 +2406,7 @@ static PPROC FindAddress(void *handle, char *name, PyObject *type)
 	   funcname -> _funcname@<n>
 	   where n is 0, 4, 8, 12, ..., 128
 	 */
-	mangled_name = _alloca(strlen(name) + 1 + 1 + 1 + 3); /* \0 _ @ %d */
+	mangled_name = alloca(strlen(name) + 1 + 1 + 1 + 3); /* \0 _ @ %d */
 	for (i = 0; i < 32; ++i) {
 		sprintf(mangled_name, "_%s@%d", name, i*4);
 		address = (PPROC)GetProcAddress(handle, mangled_name);
@@ -2557,14 +2561,14 @@ CFuncPtr_FromDll(PyTypeObject *type, PyObject *args, PyObject *kwds)
 #ifdef MS_WIN32
 	address = FindAddress(handle, name, (PyObject *)type);
 	if (!address) {
-		if ((size_t)name & ~0xFFFF)
+		if (!IS_INTRESOURCE(name))
 			PyErr_Format(PyExc_AttributeError,
 				     "function '%s' not found",
 				     name);
 		else
 			PyErr_Format(PyExc_AttributeError,
 				     "function ordinal %d not found",
-				     name);
+				     (WORD)(size_t)name);
 		return NULL;
 	}
 #else
@@ -2651,7 +2655,7 @@ CFuncPtr_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 	CFuncPtrObject *self;
 	PyObject *callable;
 	StgDictObject *dict;
-	THUNK thunk;
+	ffi_info *thunk;
 
 	if (PyTuple_GET_SIZE(args) == 0)
 		return GenericCData_new(type, args, kwds);
@@ -3192,10 +3196,10 @@ CFuncPtr_clear(CFuncPtrObject *self)
 	Py_CLEAR(self->paramflags);
 
 	if (self->thunk) {
-		FreeCallback(self->thunk);
+		FreeClosure(self->thunk->pcl);
 		PyMem_Free(self->thunk);
-	}
 		self->thunk = NULL;
+	}
 
 	return CData_clear((CDataObject *)self);
 }

Modules/_ctypes/callbacks.c

@@ -264,16 +264,6 @@ if (x == NULL) _AddTraceback(what, __FILE__, __LINE__ - 1), PyErr_Print()
 	PyGILState_Release(state);
 }
 
-typedef struct {
-	ffi_closure *pcl; /* the C callable */
-	ffi_cif cif;
-	PyObject *converters;
-	PyObject *callable;
-	SETFUNC setfunc;
-	ffi_type *restype;
-	ffi_type *atypes[0];
-} ffi_info;
-
 static void closure_fcn(ffi_cif *cif,
 			void *resp,
 			void **args,
@@ -289,12 +279,7 @@ static void closure_fcn(ffi_cif *cif,
 			  args);
 }
 
-void FreeCallback(THUNK thunk)
-{
-	FreeClosure(((ffi_info *)thunk)->pcl);
-}
-
-THUNK AllocFunctionCallback(PyObject *callable,
+ffi_info *AllocFunctionCallback(PyObject *callable,
 				PyObject *converters,
 				PyObject *restype,
 				int is_cdecl)
@@ -306,8 +291,10 @@ THUNK AllocFunctionCallback(PyObject *callable,
 
 	nArgs = PySequence_Size(converters);
 	p = (ffi_info *)PyMem_Malloc(sizeof(ffi_info) + sizeof(ffi_type) * (nArgs + 1));
-	if (p == NULL)
-		return (THUNK)PyErr_NoMemory();
+	if (p == NULL) {
+		PyErr_NoMemory();
+		return NULL;
+	}
 	p->pcl = MallocClosure();
 	if (p->pcl == NULL) {
 		PyErr_NoMemory();
@@ -356,11 +343,12 @@ THUNK AllocFunctionCallback(PyObject *callable,
 
 	p->converters = converters;
 	p->callable = callable;
-	return (THUNK)p;
+	return p;
 
   error:
 	if (p) {
-		FreeCallback((THUNK)p);
+		if (p->pcl)
+			FreeClosure(p->pcl);
 		PyMem_Free(p);
 	}
 	return NULL;

Modules/_ctypes/callproc.c

@@ -64,14 +64,17 @@
 #endif
 
 #ifdef MS_WIN32
-#define alloca _alloca
+#include <malloc.h>
 #endif
 
 #include <ffi.h>
 #include "ctypes.h"
 
-#ifdef _DEBUG
-#define DEBUG_EXCEPTIONS /* */
+#if defined(_DEBUG) || defined(__MINGW32__)
+/* Don't use structured exception handling on Windows if this is defined.
+   MingW, AFAIK, doesn't support it.
+*/
+#define DONT_USE_SEH
 #endif
 
 #ifdef MS_WIN32
@@ -96,6 +99,7 @@ static TCHAR *FormatError(DWORD code)
 	return lpMsgBuf;
 }
 
+#ifndef DONT_USE_SEH
 void SetException(DWORD code, EXCEPTION_RECORD *pr)
 {
 	TCHAR *lpMsgBuf;
@@ -254,6 +258,7 @@ static DWORD HandleException(EXCEPTION_POINTERS *ptrs,
 	*record = *ptrs->ExceptionRecord;
 	return EXCEPTION_EXECUTE_HANDLER;
 }
+#endif
 
 static PyObject *
 check_hresult(PyObject *self, PyObject *args)
@@ -612,8 +617,10 @@ static int _call_function_pointer(int flags,
 	int cc;
 #ifdef MS_WIN32
 	int delta;
+#ifndef DONT_USE_SEH
 	DWORD dwExceptionCode = 0;
 	EXCEPTION_RECORD record;
+#endif
 #endif
 	/* XXX check before here */
 	if (restype == NULL) {
@@ -640,14 +647,14 @@ static int _call_function_pointer(int flags,
 	if ((flags & FUNCFLAG_PYTHONAPI) == 0)
 		Py_UNBLOCK_THREADS
 #ifdef MS_WIN32
-#ifndef DEBUG_EXCEPTIONS
+#ifndef DONT_USE_SEH
 	__try {
 #endif
 		delta =
 #endif
 			ffi_call(&cif, (void *)pProc, resmem, avalues);
 #ifdef MS_WIN32
-#ifndef DEBUG_EXCEPTIONS
+#ifndef DONT_USE_SEH
 	}
 	__except (HandleException(GetExceptionInformation(),
 				  &dwExceptionCode, &record)) {
@@ -658,10 +665,12 @@ static int _call_function_pointer(int flags,
 	if ((flags & FUNCFLAG_PYTHONAPI) == 0)
 		Py_BLOCK_THREADS
 #ifdef MS_WIN32
+#ifndef DONT_USE_SEH
 	if (dwExceptionCode) {
 		SetException(dwExceptionCode, &record);
 		return -1;
 	}
+#endif
 	if (delta < 0) {
 		if (flags & FUNCFLAG_CDECL)
 			PyErr_Format(PyExc_ValueError,

Modules/_ctypes/ctypes.h

@@ -21,8 +21,9 @@ typedef int Py_ssize_t;
 #define PY_LONG_LONG LONG_LONG
 #endif
 
-typedef int (*THUNK)(void);
 typedef struct tagCDataObject CDataObject;
+typedef PyObject *(* GETFUNC)(void *, unsigned size);
+typedef PyObject *(* SETFUNC)(void *, PyObject *value, unsigned size);
 
 /* A default buffer in CDataObject, which can be used for small C types.  If
 this buffer is too small, PyMem_Malloc will be called to create a larger one,
@@ -62,6 +63,16 @@ struct tagCDataObject {
 	union value b_value;
 };
 
+typedef struct {
+	ffi_closure *pcl; /* the C callable */
+	ffi_cif cif;
+	PyObject *converters;
+	PyObject *callable;
+	SETFUNC setfunc;
+	ffi_type *restype;
+	ffi_type *atypes[0];
+} ffi_info;
+
 typedef struct {
 	/* First part identical to tagCDataObject */
 	PyObject_HEAD
@@ -76,7 +87,7 @@ typedef struct {
 	union value b_value;
 	/* end of tagCDataObject, additional fields follow */
 
-	THUNK thunk;
+	ffi_info *thunk;
 	PyObject *callable;
 
 	/* These two fields will override the ones in the type's stgdict if
@@ -145,17 +156,12 @@ CreateArrayType(PyObject *itemtype, Py_ssize_t length);
 
 extern void init_callbacks_in_module(PyObject *m);
 
-extern THUNK AllocFunctionCallback(PyObject *callable,
+extern PyMethodDef module_methods[];
+
+extern ffi_info *AllocFunctionCallback(PyObject *callable,
 				       PyObject *converters,
 				       PyObject *restype,
 				       int stdcall);
-extern void FreeCallback(THUNK);
-
-extern PyMethodDef module_methods[];
-
-typedef PyObject *(* GETFUNC)(void *, unsigned size);
-typedef PyObject *(* SETFUNC)(void *, PyObject *value, unsigned size);
-
 /* a table entry describing a predefined ctypes type */
 struct fielddesc {
 	char code;