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-rw-r--r--.venv/lib/python3.12/site-packages/cffi/vengine_gen.py679
1 files changed, 679 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/cffi/vengine_gen.py b/.venv/lib/python3.12/site-packages/cffi/vengine_gen.py
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index 00000000..bffc8212
--- /dev/null
+++ b/.venv/lib/python3.12/site-packages/cffi/vengine_gen.py
@@ -0,0 +1,679 @@
+#
+# DEPRECATED: implementation for ffi.verify()
+#
+import sys, os
+import types
+
+from . import model
+from .error import VerificationError
+
+
+class VGenericEngine(object):
+    _class_key = 'g'
+    _gen_python_module = False
+
+    def __init__(self, verifier):
+        self.verifier = verifier
+        self.ffi = verifier.ffi
+        self.export_symbols = []
+        self._struct_pending_verification = {}
+
+    def patch_extension_kwds(self, kwds):
+        # add 'export_symbols' to the dictionary.  Note that we add the
+        # list before filling it.  When we fill it, it will thus also show
+        # up in kwds['export_symbols'].
+        kwds.setdefault('export_symbols', self.export_symbols)
+
+    def find_module(self, module_name, path, so_suffixes):
+        for so_suffix in so_suffixes:
+            basename = module_name + so_suffix
+            if path is None:
+                path = sys.path
+            for dirname in path:
+                filename = os.path.join(dirname, basename)
+                if os.path.isfile(filename):
+                    return filename
+
+    def collect_types(self):
+        pass      # not needed in the generic engine
+
+    def _prnt(self, what=''):
+        self._f.write(what + '\n')
+
+    def write_source_to_f(self):
+        prnt = self._prnt
+        # first paste some standard set of lines that are mostly '#include'
+        prnt(cffimod_header)
+        # then paste the C source given by the user, verbatim.
+        prnt(self.verifier.preamble)
+        #
+        # call generate_gen_xxx_decl(), for every xxx found from
+        # ffi._parser._declarations.  This generates all the functions.
+        self._generate('decl')
+        #
+        # on Windows, distutils insists on putting init_cffi_xyz in
+        # 'export_symbols', so instead of fighting it, just give up and
+        # give it one
+        if sys.platform == 'win32':
+            if sys.version_info >= (3,):
+                prefix = 'PyInit_'
+            else:
+                prefix = 'init'
+            modname = self.verifier.get_module_name()
+            prnt("void %s%s(void) { }\n" % (prefix, modname))
+
+    def load_library(self, flags=0):
+        # import it with the CFFI backend
+        backend = self.ffi._backend
+        # needs to make a path that contains '/', on Posix
+        filename = os.path.join(os.curdir, self.verifier.modulefilename)
+        module = backend.load_library(filename, flags)
+        #
+        # call loading_gen_struct() to get the struct layout inferred by
+        # the C compiler
+        self._load(module, 'loading')
+
+        # build the FFILibrary class and instance, this is a module subclass
+        # because modules are expected to have usually-constant-attributes and
+        # in PyPy this means the JIT is able to treat attributes as constant,
+        # which we want.
+        class FFILibrary(types.ModuleType):
+            _cffi_generic_module = module
+            _cffi_ffi = self.ffi
+            _cffi_dir = []
+            def __dir__(self):
+                return FFILibrary._cffi_dir
+        library = FFILibrary("")
+        #
+        # finally, call the loaded_gen_xxx() functions.  This will set
+        # up the 'library' object.
+        self._load(module, 'loaded', library=library)
+        return library
+
+    def _get_declarations(self):
+        lst = [(key, tp) for (key, (tp, qual)) in
+                                self.ffi._parser._declarations.items()]
+        lst.sort()
+        return lst
+
+    def _generate(self, step_name):
+        for name, tp in self._get_declarations():
+            kind, realname = name.split(' ', 1)
+            try:
+                method = getattr(self, '_generate_gen_%s_%s' % (kind,
+                                                                step_name))
+            except AttributeError:
+                raise VerificationError(
+                    "not implemented in verify(): %r" % name)
+            try:
+                method(tp, realname)
+            except Exception as e:
+                model.attach_exception_info(e, name)
+                raise
+
+    def _load(self, module, step_name, **kwds):
+        for name, tp in self._get_declarations():
+            kind, realname = name.split(' ', 1)
+            method = getattr(self, '_%s_gen_%s' % (step_name, kind))
+            try:
+                method(tp, realname, module, **kwds)
+            except Exception as e:
+                model.attach_exception_info(e, name)
+                raise
+
+    def _generate_nothing(self, tp, name):
+        pass
+
+    def _loaded_noop(self, tp, name, module, **kwds):
+        pass
+
+    # ----------
+    # typedefs: generates no code so far
+
+    _generate_gen_typedef_decl   = _generate_nothing
+    _loading_gen_typedef         = _loaded_noop
+    _loaded_gen_typedef          = _loaded_noop
+
+    # ----------
+    # function declarations
+
+    def _generate_gen_function_decl(self, tp, name):
+        assert isinstance(tp, model.FunctionPtrType)
+        if tp.ellipsis:
+            # cannot support vararg functions better than this: check for its
+            # exact type (including the fixed arguments), and build it as a
+            # constant function pointer (no _cffi_f_%s wrapper)
+            self._generate_gen_const(False, name, tp)
+            return
+        prnt = self._prnt
+        numargs = len(tp.args)
+        argnames = []
+        for i, type in enumerate(tp.args):
+            indirection = ''
+            if isinstance(type, model.StructOrUnion):
+                indirection = '*'
+            argnames.append('%sx%d' % (indirection, i))
+        context = 'argument of %s' % name
+        arglist = [type.get_c_name(' %s' % arg, context)
+                   for type, arg in zip(tp.args, argnames)]
+        tpresult = tp.result
+        if isinstance(tpresult, model.StructOrUnion):
+            arglist.insert(0, tpresult.get_c_name(' *r', context))
+            tpresult = model.void_type
+        arglist = ', '.join(arglist) or 'void'
+        wrappername = '_cffi_f_%s' % name
+        self.export_symbols.append(wrappername)
+        if tp.abi:
+            abi = tp.abi + ' '
+        else:
+            abi = ''
+        funcdecl = ' %s%s(%s)' % (abi, wrappername, arglist)
+        context = 'result of %s' % name
+        prnt(tpresult.get_c_name(funcdecl, context))
+        prnt('{')
+        #
+        if isinstance(tp.result, model.StructOrUnion):
+            result_code = '*r = '
+        elif not isinstance(tp.result, model.VoidType):
+            result_code = 'return '
+        else:
+            result_code = ''
+        prnt('  %s%s(%s);' % (result_code, name, ', '.join(argnames)))
+        prnt('}')
+        prnt()
+
+    _loading_gen_function = _loaded_noop
+
+    def _loaded_gen_function(self, tp, name, module, library):
+        assert isinstance(tp, model.FunctionPtrType)
+        if tp.ellipsis:
+            newfunction = self._load_constant(False, tp, name, module)
+        else:
+            indirections = []
+            base_tp = tp
+            if (any(isinstance(typ, model.StructOrUnion) for typ in tp.args)
+                    or isinstance(tp.result, model.StructOrUnion)):
+                indirect_args = []
+                for i, typ in enumerate(tp.args):
+                    if isinstance(typ, model.StructOrUnion):
+                        typ = model.PointerType(typ)
+                        indirections.append((i, typ))
+                    indirect_args.append(typ)
+                indirect_result = tp.result
+                if isinstance(indirect_result, model.StructOrUnion):
+                    if indirect_result.fldtypes is None:
+                        raise TypeError("'%s' is used as result type, "
+                                        "but is opaque" % (
+                                            indirect_result._get_c_name(),))
+                    indirect_result = model.PointerType(indirect_result)
+                    indirect_args.insert(0, indirect_result)
+                    indirections.insert(0, ("result", indirect_result))
+                    indirect_result = model.void_type
+                tp = model.FunctionPtrType(tuple(indirect_args),
+                                           indirect_result, tp.ellipsis)
+            BFunc = self.ffi._get_cached_btype(tp)
+            wrappername = '_cffi_f_%s' % name
+            newfunction = module.load_function(BFunc, wrappername)
+            for i, typ in indirections:
+                newfunction = self._make_struct_wrapper(newfunction, i, typ,
+                                                        base_tp)
+        setattr(library, name, newfunction)
+        type(library)._cffi_dir.append(name)
+
+    def _make_struct_wrapper(self, oldfunc, i, tp, base_tp):
+        backend = self.ffi._backend
+        BType = self.ffi._get_cached_btype(tp)
+        if i == "result":
+            ffi = self.ffi
+            def newfunc(*args):
+                res = ffi.new(BType)
+                oldfunc(res, *args)
+                return res[0]
+        else:
+            def newfunc(*args):
+                args = args[:i] + (backend.newp(BType, args[i]),) + args[i+1:]
+                return oldfunc(*args)
+        newfunc._cffi_base_type = base_tp
+        return newfunc
+
+    # ----------
+    # named structs
+
+    def _generate_gen_struct_decl(self, tp, name):
+        assert name == tp.name
+        self._generate_struct_or_union_decl(tp, 'struct', name)
+
+    def _loading_gen_struct(self, tp, name, module):
+        self._loading_struct_or_union(tp, 'struct', name, module)
+
+    def _loaded_gen_struct(self, tp, name, module, **kwds):
+        self._loaded_struct_or_union(tp)
+
+    def _generate_gen_union_decl(self, tp, name):
+        assert name == tp.name
+        self._generate_struct_or_union_decl(tp, 'union', name)
+
+    def _loading_gen_union(self, tp, name, module):
+        self._loading_struct_or_union(tp, 'union', name, module)
+
+    def _loaded_gen_union(self, tp, name, module, **kwds):
+        self._loaded_struct_or_union(tp)
+
+    def _generate_struct_or_union_decl(self, tp, prefix, name):
+        if tp.fldnames is None:
+            return     # nothing to do with opaque structs
+        checkfuncname = '_cffi_check_%s_%s' % (prefix, name)
+        layoutfuncname = '_cffi_layout_%s_%s' % (prefix, name)
+        cname = ('%s %s' % (prefix, name)).strip()
+        #
+        prnt = self._prnt
+        prnt('static void %s(%s *p)' % (checkfuncname, cname))
+        prnt('{')
+        prnt('  /* only to generate compile-time warnings or errors */')
+        prnt('  (void)p;')
+        for fname, ftype, fbitsize, fqual in tp.enumfields():
+            if (isinstance(ftype, model.PrimitiveType)
+                and ftype.is_integer_type()) or fbitsize >= 0:
+                # accept all integers, but complain on float or double
+                prnt('  (void)((p->%s) << 1);' % fname)
+            else:
+                # only accept exactly the type declared.
+                try:
+                    prnt('  { %s = &p->%s; (void)tmp; }' % (
+                        ftype.get_c_name('*tmp', 'field %r'%fname, quals=fqual),
+                        fname))
+                except VerificationError as e:
+                    prnt('  /* %s */' % str(e))   # cannot verify it, ignore
+        prnt('}')
+        self.export_symbols.append(layoutfuncname)
+        prnt('intptr_t %s(intptr_t i)' % (layoutfuncname,))
+        prnt('{')
+        prnt('  struct _cffi_aligncheck { char x; %s y; };' % cname)
+        prnt('  static intptr_t nums[] = {')
+        prnt('    sizeof(%s),' % cname)
+        prnt('    offsetof(struct _cffi_aligncheck, y),')
+        for fname, ftype, fbitsize, fqual in tp.enumfields():
+            if fbitsize >= 0:
+                continue      # xxx ignore fbitsize for now
+            prnt('    offsetof(%s, %s),' % (cname, fname))
+            if isinstance(ftype, model.ArrayType) and ftype.length is None:
+                prnt('    0,  /* %s */' % ftype._get_c_name())
+            else:
+                prnt('    sizeof(((%s *)0)->%s),' % (cname, fname))
+        prnt('    -1')
+        prnt('  };')
+        prnt('  return nums[i];')
+        prnt('  /* the next line is not executed, but compiled */')
+        prnt('  %s(0);' % (checkfuncname,))
+        prnt('}')
+        prnt()
+
+    def _loading_struct_or_union(self, tp, prefix, name, module):
+        if tp.fldnames is None:
+            return     # nothing to do with opaque structs
+        layoutfuncname = '_cffi_layout_%s_%s' % (prefix, name)
+        #
+        BFunc = self.ffi._typeof_locked("intptr_t(*)(intptr_t)")[0]
+        function = module.load_function(BFunc, layoutfuncname)
+        layout = []
+        num = 0
+        while True:
+            x = function(num)
+            if x < 0: break
+            layout.append(x)
+            num += 1
+        if isinstance(tp, model.StructOrUnion) and tp.partial:
+            # use the function()'s sizes and offsets to guide the
+            # layout of the struct
+            totalsize = layout[0]
+            totalalignment = layout[1]
+            fieldofs = layout[2::2]
+            fieldsize = layout[3::2]
+            tp.force_flatten()
+            assert len(fieldofs) == len(fieldsize) == len(tp.fldnames)
+            tp.fixedlayout = fieldofs, fieldsize, totalsize, totalalignment
+        else:
+            cname = ('%s %s' % (prefix, name)).strip()
+            self._struct_pending_verification[tp] = layout, cname
+
+    def _loaded_struct_or_union(self, tp):
+        if tp.fldnames is None:
+            return     # nothing to do with opaque structs
+        self.ffi._get_cached_btype(tp)   # force 'fixedlayout' to be considered
+
+        if tp in self._struct_pending_verification:
+            # check that the layout sizes and offsets match the real ones
+            def check(realvalue, expectedvalue, msg):
+                if realvalue != expectedvalue:
+                    raise VerificationError(
+                        "%s (we have %d, but C compiler says %d)"
+                        % (msg, expectedvalue, realvalue))
+            ffi = self.ffi
+            BStruct = ffi._get_cached_btype(tp)
+            layout, cname = self._struct_pending_verification.pop(tp)
+            check(layout[0], ffi.sizeof(BStruct), "wrong total size")
+            check(layout[1], ffi.alignof(BStruct), "wrong total alignment")
+            i = 2
+            for fname, ftype, fbitsize, fqual in tp.enumfields():
+                if fbitsize >= 0:
+                    continue        # xxx ignore fbitsize for now
+                check(layout[i], ffi.offsetof(BStruct, fname),
+                      "wrong offset for field %r" % (fname,))
+                if layout[i+1] != 0:
+                    BField = ffi._get_cached_btype(ftype)
+                    check(layout[i+1], ffi.sizeof(BField),
+                          "wrong size for field %r" % (fname,))
+                i += 2
+            assert i == len(layout)
+
+    # ----------
+    # 'anonymous' declarations.  These are produced for anonymous structs
+    # or unions; the 'name' is obtained by a typedef.
+
+    def _generate_gen_anonymous_decl(self, tp, name):
+        if isinstance(tp, model.EnumType):
+            self._generate_gen_enum_decl(tp, name, '')
+        else:
+            self._generate_struct_or_union_decl(tp, '', name)
+
+    def _loading_gen_anonymous(self, tp, name, module):
+        if isinstance(tp, model.EnumType):
+            self._loading_gen_enum(tp, name, module, '')
+        else:
+            self._loading_struct_or_union(tp, '', name, module)
+
+    def _loaded_gen_anonymous(self, tp, name, module, **kwds):
+        if isinstance(tp, model.EnumType):
+            self._loaded_gen_enum(tp, name, module, **kwds)
+        else:
+            self._loaded_struct_or_union(tp)
+
+    # ----------
+    # constants, likely declared with '#define'
+
+    def _generate_gen_const(self, is_int, name, tp=None, category='const',
+                            check_value=None):
+        prnt = self._prnt
+        funcname = '_cffi_%s_%s' % (category, name)
+        self.export_symbols.append(funcname)
+        if check_value is not None:
+            assert is_int
+            assert category == 'const'
+            prnt('int %s(char *out_error)' % funcname)
+            prnt('{')
+            self._check_int_constant_value(name, check_value)
+            prnt('  return 0;')
+            prnt('}')
+        elif is_int:
+            assert category == 'const'
+            prnt('int %s(long long *out_value)' % funcname)
+            prnt('{')
+            prnt('  *out_value = (long long)(%s);' % (name,))
+            prnt('  return (%s) <= 0;' % (name,))
+            prnt('}')
+        else:
+            assert tp is not None
+            assert check_value is None
+            if category == 'var':
+                ampersand = '&'
+            else:
+                ampersand = ''
+            extra = ''
+            if category == 'const' and isinstance(tp, model.StructOrUnion):
+                extra = 'const *'
+                ampersand = '&'
+            prnt(tp.get_c_name(' %s%s(void)' % (extra, funcname), name))
+            prnt('{')
+            prnt('  return (%s%s);' % (ampersand, name))
+            prnt('}')
+        prnt()
+
+    def _generate_gen_constant_decl(self, tp, name):
+        is_int = isinstance(tp, model.PrimitiveType) and tp.is_integer_type()
+        self._generate_gen_const(is_int, name, tp)
+
+    _loading_gen_constant = _loaded_noop
+
+    def _load_constant(self, is_int, tp, name, module, check_value=None):
+        funcname = '_cffi_const_%s' % name
+        if check_value is not None:
+            assert is_int
+            self._load_known_int_constant(module, funcname)
+            value = check_value
+        elif is_int:
+            BType = self.ffi._typeof_locked("long long*")[0]
+            BFunc = self.ffi._typeof_locked("int(*)(long long*)")[0]
+            function = module.load_function(BFunc, funcname)
+            p = self.ffi.new(BType)
+            negative = function(p)
+            value = int(p[0])
+            if value < 0 and not negative:
+                BLongLong = self.ffi._typeof_locked("long long")[0]
+                value += (1 << (8*self.ffi.sizeof(BLongLong)))
+        else:
+            assert check_value is None
+            fntypeextra = '(*)(void)'
+            if isinstance(tp, model.StructOrUnion):
+                fntypeextra = '*' + fntypeextra
+            BFunc = self.ffi._typeof_locked(tp.get_c_name(fntypeextra, name))[0]
+            function = module.load_function(BFunc, funcname)
+            value = function()
+            if isinstance(tp, model.StructOrUnion):
+                value = value[0]
+        return value
+
+    def _loaded_gen_constant(self, tp, name, module, library):
+        is_int = isinstance(tp, model.PrimitiveType) and tp.is_integer_type()
+        value = self._load_constant(is_int, tp, name, module)
+        setattr(library, name, value)
+        type(library)._cffi_dir.append(name)
+
+    # ----------
+    # enums
+
+    def _check_int_constant_value(self, name, value):
+        prnt = self._prnt
+        if value <= 0:
+            prnt('  if ((%s) > 0 || (long)(%s) != %dL) {' % (
+                name, name, value))
+        else:
+            prnt('  if ((%s) <= 0 || (unsigned long)(%s) != %dUL) {' % (
+                name, name, value))
+        prnt('    char buf[64];')
+        prnt('    if ((%s) <= 0)' % name)
+        prnt('        sprintf(buf, "%%ld", (long)(%s));' % name)
+        prnt('    else')
+        prnt('        sprintf(buf, "%%lu", (unsigned long)(%s));' %
+             name)
+        prnt('    sprintf(out_error, "%s has the real value %s, not %s",')
+        prnt('            "%s", buf, "%d");' % (name[:100], value))
+        prnt('    return -1;')
+        prnt('  }')
+
+    def _load_known_int_constant(self, module, funcname):
+        BType = self.ffi._typeof_locked("char[]")[0]
+        BFunc = self.ffi._typeof_locked("int(*)(char*)")[0]
+        function = module.load_function(BFunc, funcname)
+        p = self.ffi.new(BType, 256)
+        if function(p) < 0:
+            error = self.ffi.string(p)
+            if sys.version_info >= (3,):
+                error = str(error, 'utf-8')
+            raise VerificationError(error)
+
+    def _enum_funcname(self, prefix, name):
+        # "$enum_$1" => "___D_enum____D_1"
+        name = name.replace('$', '___D_')
+        return '_cffi_e_%s_%s' % (prefix, name)
+
+    def _generate_gen_enum_decl(self, tp, name, prefix='enum'):
+        if tp.partial:
+            for enumerator in tp.enumerators:
+                self._generate_gen_const(True, enumerator)
+            return
+        #
+        funcname = self._enum_funcname(prefix, name)
+        self.export_symbols.append(funcname)
+        prnt = self._prnt
+        prnt('int %s(char *out_error)' % funcname)
+        prnt('{')
+        for enumerator, enumvalue in zip(tp.enumerators, tp.enumvalues):
+            self._check_int_constant_value(enumerator, enumvalue)
+        prnt('  return 0;')
+        prnt('}')
+        prnt()
+
+    def _loading_gen_enum(self, tp, name, module, prefix='enum'):
+        if tp.partial:
+            enumvalues = [self._load_constant(True, tp, enumerator, module)
+                          for enumerator in tp.enumerators]
+            tp.enumvalues = tuple(enumvalues)
+            tp.partial_resolved = True
+        else:
+            funcname = self._enum_funcname(prefix, name)
+            self._load_known_int_constant(module, funcname)
+
+    def _loaded_gen_enum(self, tp, name, module, library):
+        for enumerator, enumvalue in zip(tp.enumerators, tp.enumvalues):
+            setattr(library, enumerator, enumvalue)
+            type(library)._cffi_dir.append(enumerator)
+
+    # ----------
+    # macros: for now only for integers
+
+    def _generate_gen_macro_decl(self, tp, name):
+        if tp == '...':
+            check_value = None
+        else:
+            check_value = tp     # an integer
+        self._generate_gen_const(True, name, check_value=check_value)
+
+    _loading_gen_macro = _loaded_noop
+
+    def _loaded_gen_macro(self, tp, name, module, library):
+        if tp == '...':
+            check_value = None
+        else:
+            check_value = tp     # an integer
+        value = self._load_constant(True, tp, name, module,
+                                    check_value=check_value)
+        setattr(library, name, value)
+        type(library)._cffi_dir.append(name)
+
+    # ----------
+    # global variables
+
+    def _generate_gen_variable_decl(self, tp, name):
+        if isinstance(tp, model.ArrayType):
+            if tp.length_is_unknown():
+                prnt = self._prnt
+                funcname = '_cffi_sizeof_%s' % (name,)
+                self.export_symbols.append(funcname)
+                prnt("size_t %s(void)" % funcname)
+                prnt("{")
+                prnt("  return sizeof(%s);" % (name,))
+                prnt("}")
+            tp_ptr = model.PointerType(tp.item)
+            self._generate_gen_const(False, name, tp_ptr)
+        else:
+            tp_ptr = model.PointerType(tp)
+            self._generate_gen_const(False, name, tp_ptr, category='var')
+
+    _loading_gen_variable = _loaded_noop
+
+    def _loaded_gen_variable(self, tp, name, module, library):
+        if isinstance(tp, model.ArrayType):   # int a[5] is "constant" in the
+                                              # sense that "a=..." is forbidden
+            if tp.length_is_unknown():
+                funcname = '_cffi_sizeof_%s' % (name,)
+                BFunc = self.ffi._typeof_locked('size_t(*)(void)')[0]
+                function = module.load_function(BFunc, funcname)
+                size = function()
+                BItemType = self.ffi._get_cached_btype(tp.item)
+                length, rest = divmod(size, self.ffi.sizeof(BItemType))
+                if rest != 0:
+                    raise VerificationError(
+                        "bad size: %r does not seem to be an array of %s" %
+                        (name, tp.item))
+                tp = tp.resolve_length(length)
+            tp_ptr = model.PointerType(tp.item)
+            value = self._load_constant(False, tp_ptr, name, module)
+            # 'value' is a <cdata 'type *'> which we have to replace with
+            # a <cdata 'type[N]'> if the N is actually known
+            if tp.length is not None:
+                BArray = self.ffi._get_cached_btype(tp)
+                value = self.ffi.cast(BArray, value)
+            setattr(library, name, value)
+            type(library)._cffi_dir.append(name)
+            return
+        # remove ptr=<cdata 'int *'> from the library instance, and replace
+        # it by a property on the class, which reads/writes into ptr[0].
+        funcname = '_cffi_var_%s' % name
+        BFunc = self.ffi._typeof_locked(tp.get_c_name('*(*)(void)', name))[0]
+        function = module.load_function(BFunc, funcname)
+        ptr = function()
+        def getter(library):
+            return ptr[0]
+        def setter(library, value):
+            ptr[0] = value
+        setattr(type(library), name, property(getter, setter))
+        type(library)._cffi_dir.append(name)
+
+cffimod_header = r'''
+#include <stdio.h>
+#include <stddef.h>
+#include <stdarg.h>
+#include <errno.h>
+#include <sys/types.h>   /* XXX for ssize_t on some platforms */
+
+/* this block of #ifs should be kept exactly identical between
+   c/_cffi_backend.c, cffi/vengine_cpy.py, cffi/vengine_gen.py
+   and cffi/_cffi_include.h */
+#if defined(_MSC_VER)
+# include <malloc.h>   /* for alloca() */
+# if _MSC_VER < 1600   /* MSVC < 2010 */
+   typedef __int8 int8_t;
+   typedef __int16 int16_t;
+   typedef __int32 int32_t;
+   typedef __int64 int64_t;
+   typedef unsigned __int8 uint8_t;
+   typedef unsigned __int16 uint16_t;
+   typedef unsigned __int32 uint32_t;
+   typedef unsigned __int64 uint64_t;
+   typedef __int8 int_least8_t;
+   typedef __int16 int_least16_t;
+   typedef __int32 int_least32_t;
+   typedef __int64 int_least64_t;
+   typedef unsigned __int8 uint_least8_t;
+   typedef unsigned __int16 uint_least16_t;
+   typedef unsigned __int32 uint_least32_t;
+   typedef unsigned __int64 uint_least64_t;
+   typedef __int8 int_fast8_t;
+   typedef __int16 int_fast16_t;
+   typedef __int32 int_fast32_t;
+   typedef __int64 int_fast64_t;
+   typedef unsigned __int8 uint_fast8_t;
+   typedef unsigned __int16 uint_fast16_t;
+   typedef unsigned __int32 uint_fast32_t;
+   typedef unsigned __int64 uint_fast64_t;
+   typedef __int64 intmax_t;
+   typedef unsigned __int64 uintmax_t;
+# else
+#  include <stdint.h>
+# endif
+# if _MSC_VER < 1800   /* MSVC < 2013 */
+#  ifndef __cplusplus
+    typedef unsigned char _Bool;
+#  endif
+# endif
+# define _cffi_float_complex_t   _Fcomplex    /* include <complex.h> for it */
+# define _cffi_double_complex_t  _Dcomplex    /* include <complex.h> for it */
+#else
+# include <stdint.h>
+# if (defined (__SVR4) && defined (__sun)) || defined(_AIX) || defined(__hpux)
+#  include <alloca.h>
+# endif
+# define _cffi_float_complex_t   float _Complex
+# define _cffi_double_complex_t  double _Complex
+#endif
+'''