PEP 3151 / issue #12555: reworking the OS and IO exception hierarchy.

Include/pyerrors.h

@@ -45,18 +45,18 @@ typedef struct {
     PyObject *myerrno;
     PyObject *strerror;
     PyObject *filename;
-} PyEnvironmentErrorObject;
-
 #ifdef MS_WINDOWS
-typedef struct {
-    PyException_HEAD
-    PyObject *myerrno;
-    PyObject *strerror;
-    PyObject *filename;
     PyObject *winerror;
-} PyWindowsErrorObject;
 #endif
+    Py_ssize_t written;   /* only for BlockingIOError, -1 otherwise */
+} PyOSErrorObject;
+
+/* Compatibility typedefs */
+typedef PyOSErrorObject PyEnvironmentErrorObject;
+#ifdef MS_WINDOWS
+typedef PyOSErrorObject PyWindowsErrorObject;
 #endif
+#endif /* !Py_LIMITED_API */
 
 /* Error handling definitions */
 
@@ -132,10 +132,9 @@ PyAPI_DATA(PyObject *) PyExc_LookupError;
 
 PyAPI_DATA(PyObject *) PyExc_AssertionError;
 PyAPI_DATA(PyObject *) PyExc_AttributeError;
+PyAPI_DATA(PyObject *) PyExc_BufferError;
 PyAPI_DATA(PyObject *) PyExc_EOFError;
 PyAPI_DATA(PyObject *) PyExc_FloatingPointError;
-PyAPI_DATA(PyObject *) PyExc_EnvironmentError;
-PyAPI_DATA(PyObject *) PyExc_IOError;
 PyAPI_DATA(PyObject *) PyExc_OSError;
 PyAPI_DATA(PyObject *) PyExc_ImportError;
 PyAPI_DATA(PyObject *) PyExc_IndexError;
@@ -160,6 +159,27 @@ PyAPI_DATA(PyObject *) PyExc_UnicodeDecodeError;
 PyAPI_DATA(PyObject *) PyExc_UnicodeTranslateError;
 PyAPI_DATA(PyObject *) PyExc_ValueError;
 PyAPI_DATA(PyObject *) PyExc_ZeroDivisionError;
+
+PyAPI_DATA(PyObject *) PyExc_BlockingIOError;
+PyAPI_DATA(PyObject *) PyExc_BrokenPipeError;
+PyAPI_DATA(PyObject *) PyExc_ChildProcessError;
+PyAPI_DATA(PyObject *) PyExc_ConnectionError;
+PyAPI_DATA(PyObject *) PyExc_ConnectionAbortedError;
+PyAPI_DATA(PyObject *) PyExc_ConnectionRefusedError;
+PyAPI_DATA(PyObject *) PyExc_ConnectionResetError;
+PyAPI_DATA(PyObject *) PyExc_FileExistsError;
+PyAPI_DATA(PyObject *) PyExc_FileNotFoundError;
+PyAPI_DATA(PyObject *) PyExc_InterruptedError;
+PyAPI_DATA(PyObject *) PyExc_IsADirectoryError;
+PyAPI_DATA(PyObject *) PyExc_NotADirectoryError;
+PyAPI_DATA(PyObject *) PyExc_PermissionError;
+PyAPI_DATA(PyObject *) PyExc_ProcessLookupError;
+PyAPI_DATA(PyObject *) PyExc_TimeoutError;
+
+
+/* Compatibility aliases */
+PyAPI_DATA(PyObject *) PyExc_EnvironmentError;
+PyAPI_DATA(PyObject *) PyExc_IOError;
 #ifdef MS_WINDOWS
 PyAPI_DATA(PyObject *) PyExc_WindowsError;
 #endif
@@ -167,8 +187,6 @@ PyAPI_DATA(PyObject *) PyExc_WindowsError;
 PyAPI_DATA(PyObject *) PyExc_VMSError;
 #endif
 
-PyAPI_DATA(PyObject *) PyExc_BufferError;
-
 PyAPI_DATA(PyObject *) PyExc_RecursionErrorInst;
 
 /* Predefined warning categories */

Lib/_pyio.py

@@ -23,16 +23,8 @@ DEFAULT_BUFFER_SIZE = 8 * 1024  # bytes
 # defined in io.py. We don't use real inheritance though, because we don't
 # want to inherit the C implementations.
 
-
-class BlockingIOError(IOError):
-
-    """Exception raised when I/O would block on a non-blocking I/O stream."""
-
-    def __init__(self, errno, strerror, characters_written=0):
-        super().__init__(errno, strerror)
-        if not isinstance(characters_written, int):
-            raise TypeError("characters_written must be a integer")
-        self.characters_written = characters_written
+# Rebind for compatibility
+BlockingIOError = BlockingIOError
 
 
 def open(file, mode="r", buffering=-1, encoding=None, errors=None,

Lib/multiprocessing/connection.py

@@ -321,7 +321,7 @@ if win32:
                     firstchunk = overlapped.getbuffer()
                     assert lenfirstchunk == len(firstchunk)
                 except IOError as e:
-                    if e.errno == win32.ERROR_BROKEN_PIPE:
+                    if e.winerror == win32.ERROR_BROKEN_PIPE:
                         raise EOFError
                     raise
                 buf.write(firstchunk)
@@ -669,7 +669,7 @@ if sys.platform == 'win32':
             try:
                 win32.ConnectNamedPipe(handle, win32.NULL)
             except WindowsError as e:
-                if e.args[0] != win32.ERROR_PIPE_CONNECTED:
+                if e.winerror != win32.ERROR_PIPE_CONNECTED:
                     raise
             return PipeConnection(handle)
 
@@ -692,7 +692,7 @@ if sys.platform == 'win32':
                     0, win32.NULL, win32.OPEN_EXISTING, 0, win32.NULL
                     )
             except WindowsError as e:
-                if e.args[0] not in (win32.ERROR_SEM_TIMEOUT,
+                if e.winerror not in (win32.ERROR_SEM_TIMEOUT,
                                       win32.ERROR_PIPE_BUSY) or _check_timeout(t):
                     raise
             else:

Lib/test/exception_hierarchy.txt

@@ -11,11 +11,6 @@ BaseException
       +-- AssertionError
       +-- AttributeError
       +-- BufferError
-      +-- EnvironmentError
-      |    +-- IOError
-      |    +-- OSError
-      |         +-- WindowsError (Windows)
-      |         +-- VMSError (VMS)
       +-- EOFError
       +-- ImportError
       +-- LookupError
@@ -24,6 +19,22 @@ BaseException
       +-- MemoryError
       +-- NameError
       |    +-- UnboundLocalError
+      +-- OSError
+      |    +-- BlockingIOError
+      |    +-- ChildProcessError
+      |    +-- ConnectionError
+      |    |    +-- BrokenPipeError
+      |    |    +-- ConnectionAbortedError
+      |    |    +-- ConnectionRefusedError
+      |    |    +-- ConnectionResetError
+      |    +-- FileExistsError
+      |    +-- FileNotFoundError
+      |    +-- InterruptedError
+      |    +-- IsADirectoryError
+      |    +-- NotADirectoryError
+      |    +-- PermissionError
+      |    +-- ProcessLookupError
+      |    +-- TimeoutError
       +-- ReferenceError
       +-- RuntimeError
       |    +-- NotImplementedError

Lib/test/test_concurrent_futures.py

@@ -34,7 +34,7 @@ PENDING_FUTURE = create_future(state=PENDING)
 RUNNING_FUTURE = create_future(state=RUNNING)
 CANCELLED_FUTURE = create_future(state=CANCELLED)
 CANCELLED_AND_NOTIFIED_FUTURE = create_future(state=CANCELLED_AND_NOTIFIED)
-EXCEPTION_FUTURE = create_future(state=FINISHED, exception=IOError())
+EXCEPTION_FUTURE = create_future(state=FINISHED, exception=OSError())
 SUCCESSFUL_FUTURE = create_future(state=FINISHED, result=42)
 
 
@@ -501,7 +501,7 @@ class FutureTests(unittest.TestCase):
                          '<Future at 0x[0-9a-f]+ state=cancelled>')
         self.assertRegex(
                 repr(EXCEPTION_FUTURE),
-                '<Future at 0x[0-9a-f]+ state=finished raised IOError>')
+                '<Future at 0x[0-9a-f]+ state=finished raised OSError>')
         self.assertRegex(
                 repr(SUCCESSFUL_FUTURE),
                 '<Future at 0x[0-9a-f]+ state=finished returned int>')
@@ -512,7 +512,7 @@ class FutureTests(unittest.TestCase):
         f2 = create_future(state=RUNNING)
         f3 = create_future(state=CANCELLED)
         f4 = create_future(state=CANCELLED_AND_NOTIFIED)
-        f5 = create_future(state=FINISHED, exception=IOError())
+        f5 = create_future(state=FINISHED, exception=OSError())
         f6 = create_future(state=FINISHED, result=5)
 
         self.assertTrue(f1.cancel())
@@ -566,7 +566,7 @@ class FutureTests(unittest.TestCase):
                           CANCELLED_FUTURE.result, timeout=0)
         self.assertRaises(futures.CancelledError,
                           CANCELLED_AND_NOTIFIED_FUTURE.result, timeout=0)
-        self.assertRaises(IOError, EXCEPTION_FUTURE.result, timeout=0)
+        self.assertRaises(OSError, EXCEPTION_FUTURE.result, timeout=0)
         self.assertEqual(SUCCESSFUL_FUTURE.result(timeout=0), 42)
 
     def test_result_with_success(self):
@@ -605,7 +605,7 @@ class FutureTests(unittest.TestCase):
         self.assertRaises(futures.CancelledError,
                           CANCELLED_AND_NOTIFIED_FUTURE.exception, timeout=0)
         self.assertTrue(isinstance(EXCEPTION_FUTURE.exception(timeout=0),
-                                   IOError))
+                                   OSError))
         self.assertEqual(SUCCESSFUL_FUTURE.exception(timeout=0), None)
 
     def test_exception_with_success(self):
@@ -614,14 +614,14 @@ class FutureTests(unittest.TestCase):
             time.sleep(1)
             with f1._condition:
                 f1._state = FINISHED
-                f1._exception = IOError()
+                f1._exception = OSError()
                 f1._condition.notify_all()
 
         f1 = create_future(state=PENDING)
         t = threading.Thread(target=notification)
         t.start()
 
-        self.assertTrue(isinstance(f1.exception(timeout=5), IOError))
+        self.assertTrue(isinstance(f1.exception(timeout=5), OSError))
 
 @test.support.reap_threads
 def test_main():

Lib/test/test_exceptions.py

@@ -46,8 +46,8 @@ class ExceptionTests(unittest.TestCase):
             fp.close()
             unlink(TESTFN)
 
-        self.raise_catch(IOError, "IOError")
-        self.assertRaises(IOError, open, 'this file does not exist', 'r')
+        self.raise_catch(OSError, "OSError")
+        self.assertRaises(OSError, open, 'this file does not exist', 'r')
 
         self.raise_catch(ImportError, "ImportError")
         self.assertRaises(ImportError, __import__, "undefined_module")
@@ -192,11 +192,35 @@ class ExceptionTests(unittest.TestCase):
         except NameError:
             pass
         else:
-            self.assertEqual(str(WindowsError(1001)), "1001")
-            self.assertEqual(str(WindowsError(1001, "message")),
-                             "[Error 1001] message")
-            self.assertEqual(WindowsError(1001, "message").errno, 22)
-            self.assertEqual(WindowsError(1001, "message").winerror, 1001)
+            self.assertIs(WindowsError, OSError)
+            self.assertEqual(str(OSError(1001)), "1001")
+            self.assertEqual(str(OSError(1001, "message")),
+                             "[Errno 1001] message")
+            # POSIX errno (9 aka EBADF) is untranslated
+            w = OSError(9, 'foo', 'bar')
+            self.assertEqual(w.errno, 9)
+            self.assertEqual(w.winerror, None)
+            self.assertEqual(str(w), "[Errno 9] foo: 'bar'")
+            # ERROR_PATH_NOT_FOUND (win error 3) becomes ENOENT (2)
+            w = OSError(0, 'foo', 'bar', 3)
+            self.assertEqual(w.errno, 2)
+            self.assertEqual(w.winerror, 3)
+            self.assertEqual(w.strerror, 'foo')
+            self.assertEqual(w.filename, 'bar')
+            self.assertEqual(str(w), "[Error 3] foo: 'bar'")
+            # Unknown win error becomes EINVAL (22)
+            w = OSError(0, 'foo', None, 1001)
+            self.assertEqual(w.errno, 22)
+            self.assertEqual(w.winerror, 1001)
+            self.assertEqual(w.strerror, 'foo')
+            self.assertEqual(w.filename, None)
+            self.assertEqual(str(w), "[Error 1001] foo")
+            # Non-numeric "errno"
+            w = OSError('bar', 'foo')
+            self.assertEqual(w.errno, 'bar')
+            self.assertEqual(w.winerror, None)
+            self.assertEqual(w.strerror, 'foo')
+            self.assertEqual(w.filename, None)
 
     def testAttributes(self):
         # test that exception attributes are happy
@@ -274,11 +298,12 @@ class ExceptionTests(unittest.TestCase):
                  'start' : 0, 'end' : 1}),
         ]
         try:
+            # More tests are in test_WindowsError
             exceptionList.append(
                 (WindowsError, (1, 'strErrorStr', 'filenameStr'),
                     {'args' : (1, 'strErrorStr'),
-                     'strerror' : 'strErrorStr', 'winerror' : 1,
-                     'errno' : 22, 'filename' : 'filenameStr'})
+                     'strerror' : 'strErrorStr', 'winerror' : None,
+                     'errno' : 1, 'filename' : 'filenameStr'})
             )
         except NameError:
             pass

Lib/test/test_http_cookiejar.py

@@ -248,18 +248,19 @@ class FileCookieJarTests(unittest.TestCase):
         self.assertEqual(c._cookies["www.acme.com"]["/"]["boo"].value, None)
 
     def test_bad_magic(self):
-        # IOErrors (eg. file doesn't exist) are allowed to propagate
+        # OSErrors (eg. file doesn't exist) are allowed to propagate
         filename = test.support.TESTFN
         for cookiejar_class in LWPCookieJar, MozillaCookieJar:
             c = cookiejar_class()
             try:
                 c.load(filename="for this test to work, a file with this "
                                 "filename should not exist")
-            except IOError as exc:
-                # exactly IOError, not LoadError
-                self.assertIs(exc.__class__, IOError)
+            except OSError as exc:
+                # an OSError subclass (likely FileNotFoundError), but not
+                # LoadError
+                self.assertIsNot(exc.__class__, LoadError)
             else:
-                self.fail("expected IOError for invalid filename")
+                self.fail("expected OSError for invalid filename")
         # Invalid contents of cookies file (eg. bad magic string)
         # causes a LoadError.
         try:

Lib/test/test_io.py

@@ -2643,12 +2643,6 @@ class MiscIOTest(unittest.TestCase):
 
     def test_blockingioerror(self):
         # Various BlockingIOError issues
-        self.assertRaises(TypeError, self.BlockingIOError)
-        self.assertRaises(TypeError, self.BlockingIOError, 1)
-        self.assertRaises(TypeError, self.BlockingIOError, 1, 2, 3, 4)
-        self.assertRaises(TypeError, self.BlockingIOError, 1, "", None)
-        b = self.BlockingIOError(1, "")
-        self.assertEqual(b.characters_written, 0)
         class C(str):
             pass
         c = C("")

Lib/test/test_mmap.py

@@ -563,8 +563,7 @@ class MmapTests(unittest.TestCase):
         f.close()
 
     def test_error(self):
-        self.assertTrue(issubclass(mmap.error, EnvironmentError))
-        self.assertIn("mmap.error", str(mmap.error))
+        self.assertIs(mmap.error, OSError)
 
     def test_io_methods(self):
         data = b"0123456789"

Lib/test/test_pep3151.py

+import builtins
+import os
+import select
+import socket
+import sys
+import unittest
+import errno
+from errno import EEXIST
+
+from test import support
+
+class SubOSError(OSError):
+    pass
+
+
+class HierarchyTest(unittest.TestCase):
+
+    def test_builtin_errors(self):
+        self.assertEqual(OSError.__name__, 'OSError')
+        self.assertIs(IOError, OSError)
+        self.assertIs(EnvironmentError, OSError)
+
+    def test_socket_errors(self):
+        self.assertIs(socket.error, IOError)
+        self.assertIs(socket.gaierror.__base__, OSError)
+        self.assertIs(socket.herror.__base__, OSError)
+        self.assertIs(socket.timeout.__base__, OSError)
+
+    def test_select_error(self):
+        self.assertIs(select.error, OSError)
+
+    # mmap.error is tested in test_mmap
+
+    _pep_map = """
+        +-- BlockingIOError        EAGAIN, EALREADY, EWOULDBLOCK, EINPROGRESS
+        +-- ChildProcessError                                          ECHILD
+        +-- ConnectionError
+            +-- BrokenPipeError                              EPIPE, ESHUTDOWN
+            +-- ConnectionAbortedError                           ECONNABORTED
+            +-- ConnectionRefusedError                           ECONNREFUSED
+            +-- ConnectionResetError                               ECONNRESET
+        +-- FileExistsError                                            EEXIST
+        +-- FileNotFoundError                                          ENOENT
+        +-- InterruptedError                                            EINTR
+        +-- IsADirectoryError                                          EISDIR
+        +-- NotADirectoryError                                        ENOTDIR
+        +-- PermissionError                                     EACCES, EPERM
+        +-- ProcessLookupError                                          ESRCH
+        +-- TimeoutError                                            ETIMEDOUT
+    """
+    def _make_map(s):
+        _map = {}
+        for line in s.splitlines():
+            line = line.strip('+- ')
+            if not line:
+                continue
+            excname, _, errnames = line.partition(' ')
+            for errname in filter(None, errnames.strip().split(', ')):
+                _map[getattr(errno, errname)] = getattr(builtins, excname)
+        return _map
+    _map = _make_map(_pep_map)
+
+    def test_errno_mapping(self):
+        # The OSError constructor maps errnos to subclasses
+        # A sample test for the basic functionality
+        e = OSError(EEXIST, "Bad file descriptor")
+        self.assertIs(type(e), FileExistsError)
+        # Exhaustive testing
+        for errcode, exc in self._map.items():
+            e = OSError(errcode, "Some message")
+            self.assertIs(type(e), exc)
+        othercodes = set(errno.errorcode) - set(self._map)
+        for errcode in othercodes:
+            e = OSError(errcode, "Some message")
+            self.assertIs(type(e), OSError)
+
+    def test_OSError_subclass_mapping(self):
+        # When constructing an OSError subclass, errno mapping isn't done
+        e = SubOSError(EEXIST, "Bad file descriptor")
+        self.assertIs(type(e), SubOSError)
+
+
+class AttributesTest(unittest.TestCase):
+
+    def test_windows_error(self):
+        if os.name == "nt":
+            self.assertIn('winerror', dir(OSError))
+        else:
+            self.assertNotIn('winerror', dir(OSError))
+
+    def test_posix_error(self):
+        e = OSError(EEXIST, "File already exists", "foo.txt")
+        self.assertEqual(e.errno, EEXIST)
+        self.assertEqual(e.args[0], EEXIST)
+        self.assertEqual(e.strerror, "File already exists")
+        self.assertEqual(e.filename, "foo.txt")
+        if os.name == "nt":
+            self.assertEqual(e.winerror, None)
+
+    @unittest.skipUnless(os.name == "nt", "Windows-specific test")
+    def test_errno_translation(self):
+        # ERROR_ALREADY_EXISTS (183) -> EEXIST
+        e = OSError(0, "File already exists", "foo.txt", 183)
+        self.assertEqual(e.winerror, 183)
+        self.assertEqual(e.errno, EEXIST)
+        self.assertEqual(e.args[0], EEXIST)
+        self.assertEqual(e.strerror, "File already exists")
+        self.assertEqual(e.filename, "foo.txt")
+
+    def test_blockingioerror(self):
+        args = ("a", "b", "c", "d", "e")
+        for n in range(6):
+            e = BlockingIOError(*args[:n])
+            with self.assertRaises(AttributeError):
+                e.characters_written
+        e = BlockingIOError("a", "b", 3)
+        self.assertEqual(e.characters_written, 3)
+        e.characters_written = 5
+        self.assertEqual(e.characters_written, 5)
+
+    # XXX VMSError not tested
+
+
+def test_main():
+    support.run_unittest(__name__)
+
+if __name__=="__main__":
+    test_main()

Lib/test/test_xml_etree.py

@@ -1339,7 +1339,7 @@ def xinclude_loader(href, parse="xml", encoding=None):
     try:
         data = XINCLUDE[href]
     except KeyError:
-        raise IOError("resource not found")
+        raise OSError("resource not found")
     if parse == "xml":
         from xml.etree.ElementTree import XML
         return XML(data)
@@ -1404,7 +1404,7 @@ def xinclude():
     >>> document = xinclude_loader("C5.xml")
     >>> ElementInclude.include(document, xinclude_loader)
     Traceback (most recent call last):
-    IOError: resource not found
+    OSError: resource not found
     >>> # print(serialize(document)) # C5
     """
 
@@ -1611,7 +1611,7 @@ def bug_xmltoolkit55():
 
 class ExceptionFile:
     def read(self, x):
-        raise IOError
+        raise OSError
 
 def xmltoolkit60():
     """
@@ -1619,7 +1619,7 @@ def xmltoolkit60():
     Handle crash in stream source.
     >>> tree = ET.parse(ExceptionFile())
     Traceback (most recent call last):
-    IOError
+    OSError
 
     """
 

Lib/urllib/request.py

@@ -1547,6 +1547,8 @@ class URLopener:
                 return getattr(self, name)(url)
             else:
                 return getattr(self, name)(url, data)
+        except HTTPError:
+            raise
         except socket.error as msg:
             raise IOError('socket error', msg).with_traceback(sys.exc_info()[2])
 

Misc/NEWS

@@ -10,6 +10,8 @@ What's New in Python 3.3 Alpha 1?
 Core and Builtins
 -----------------
 
+- PEP 3151 / issue #12555: reworking the OS and IO exception hierarchy.
+
 - Add internal API for static strings (_Py_identifier et.al.).
 
 - Issue #13063: the Windows error ERROR_NO_DATA (numbered 232 and described

Modules/_io/_iomodule.c

@@ -90,89 +90,6 @@ PyDoc_STRVAR(module_doc,
     );
 
 
-/*
- * BlockingIOError extends IOError
- */
-
-static int
-blockingioerror_init(PyBlockingIOErrorObject *self, PyObject *args,
-                     PyObject *kwds)
-{
-    PyObject *myerrno = NULL, *strerror = NULL;
-    PyObject *baseargs = NULL;
-    Py_ssize_t written = 0;
-
-    assert(PyTuple_Check(args));
-
-    self->written = 0;
-    if (!PyArg_ParseTuple(args, "OO|n:BlockingIOError",
-                          &myerrno, &strerror, &written))
-        return -1;
-
-    baseargs = PyTuple_Pack(2, myerrno, strerror);
-    if (baseargs == NULL)
-        return -1;
-    /* This will take care of initializing of myerrno and strerror members */
-    if (((PyTypeObject *)PyExc_IOError)->tp_init(
-                (PyObject *)self, baseargs, kwds) == -1) {
-        Py_DECREF(baseargs);
-        return -1;
-    }
-    Py_DECREF(baseargs);
-
-    self->written = written;
-    return 0;
-}
-
-static PyMemberDef blockingioerror_members[] = {
-    {"characters_written", T_PYSSIZET, offsetof(PyBlockingIOErrorObject, written), 0},
-    {NULL}  /* Sentinel */
-};
-
-static PyTypeObject _PyExc_BlockingIOError = {
-    PyVarObject_HEAD_INIT(NULL, 0)
-    "BlockingIOError", /*tp_name*/
-    sizeof(PyBlockingIOErrorObject), /*tp_basicsize*/
-    0,                          /*tp_itemsize*/
-    0,                          /*tp_dealloc*/
-    0,                          /*tp_print*/
-    0,                          /*tp_getattr*/
-    0,                          /*tp_setattr*/
-    0,                          /*tp_compare */
-    0,                          /*tp_repr*/
-    0,                          /*tp_as_number*/
-    0,                          /*tp_as_sequence*/
-    0,                          /*tp_as_mapping*/
-    0,                          /*tp_hash */
-    0,                          /*tp_call*/
-    0,                          /*tp_str*/
-    0,                          /*tp_getattro*/
-    0,                          /*tp_setattro*/
-    0,                          /*tp_as_buffer*/
-    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
-    PyDoc_STR("Exception raised when I/O would block "
-              "on a non-blocking I/O stream"), /* tp_doc */
-    0,                          /* tp_traverse */
-    0,                          /* tp_clear */
-    0,                          /* tp_richcompare */
-    0,                          /* tp_weaklistoffset */
-    0,                          /* tp_iter */
-    0,                          /* tp_iternext */
-    0,                          /* tp_methods */
-    blockingioerror_members,    /* tp_members */
-    0,                          /* tp_getset */
-    0,                          /* tp_base */
-    0,                          /* tp_dict */
-    0,                          /* tp_descr_get */
-    0,                          /* tp_descr_set */
-    0,                          /* tp_dictoffset */
-    (initproc)blockingioerror_init, /* tp_init */
-    0,                          /* tp_alloc */
-    0,                          /* tp_new */
-};
-PyObject *PyExc_BlockingIOError = (PyObject *)&_PyExc_BlockingIOError;
-
-
 /*
  * The main open() function
  */
@@ -694,9 +611,11 @@ PyInit__io(void)
                            state->unsupported_operation) < 0)
         goto fail;
 
-    /* BlockingIOError */
-    _PyExc_BlockingIOError.tp_base = (PyTypeObject *) PyExc_IOError;
-    ADD_TYPE(&_PyExc_BlockingIOError, "BlockingIOError");
+    /* BlockingIOError, for compatibility */
+    Py_INCREF(PyExc_BlockingIOError);
+    if (PyModule_AddObject(m, "BlockingIOError",
+                           (PyObject *) PyExc_BlockingIOError) < 0)
+        goto fail;
 
     /* Concrete base types of the IO ABCs.
        (the ABCs themselves are declared through inheritance in io.py)

Modules/_io/_iomodule.h

@@ -60,15 +60,6 @@ extern Py_ssize_t _PyIO_find_line_ending(
 
 #define DEFAULT_BUFFER_SIZE (8 * 1024)  /* bytes */
 
-typedef struct {
-    PyException_HEAD
-    PyObject *myerrno;
-    PyObject *strerror;
-    PyObject *filename; /* Not used, but part of the IOError object */
-    Py_ssize_t written;
-} PyBlockingIOErrorObject;
-PyAPI_DATA(PyObject *) PyExc_BlockingIOError;
-
 /*
  * Offset type for positioning.
  */

Modules/_io/bufferedio.c

@@ -622,14 +622,14 @@ static Py_ssize_t *
 _buffered_check_blocking_error(void)
 {
     PyObject *t, *v, *tb;
-    PyBlockingIOErrorObject *err;
+    PyOSErrorObject *err;
 
     PyErr_Fetch(&t, &v, &tb);
     if (v == NULL || !PyErr_GivenExceptionMatches(v, PyExc_BlockingIOError)) {
         PyErr_Restore(t, v, tb);
         return NULL;
     }
-    err = (PyBlockingIOErrorObject *) v;
+    err = (PyOSErrorObject *) v;
     /* TODO: sanity check (err->written >= 0) */
     PyErr_Restore(t, v, tb);
     return &err->written;

Modules/mmapmodule.c

@@ -78,8 +78,6 @@ my_getpagesize(void)
 #  define MAP_ANONYMOUS MAP_ANON
 #endif
 
-static PyObject *mmap_module_error;
-
 typedef enum
 {
     ACCESS_DEFAULT,
@@ -459,7 +457,7 @@ mmap_size_method(mmap_object *self,
     {
         struct stat buf;
         if (-1 == fstat(self->fd, &buf)) {
-            PyErr_SetFromErrno(mmap_module_error);
+            PyErr_SetFromErrno(PyExc_OSError);
             return NULL;
         }
 #ifdef HAVE_LARGEFILE_SUPPORT
@@ -549,7 +547,7 @@ mmap_resize_method(mmap_object *self,
         void *newmap;
 
         if (ftruncate(self->fd, self->offset + new_size) == -1) {
-            PyErr_SetFromErrno(mmap_module_error);
+            PyErr_SetFromErrno(PyExc_OSError);
             return NULL;
         }
 
@@ -564,7 +562,7 @@ mmap_resize_method(mmap_object *self,
 #endif
         if (newmap == (void *)-1)
         {
-            PyErr_SetFromErrno(mmap_module_error);
+            PyErr_SetFromErrno(PyExc_OSError);
             return NULL;
         }
         self->data = newmap;
@@ -605,7 +603,7 @@ mmap_flush_method(mmap_object *self, PyObject *args)
     /* XXX semantics of return value? */
     /* XXX flags for msync? */
     if (-1 == msync(self->data + offset, size, MS_SYNC)) {
-        PyErr_SetFromErrno(mmap_module_error);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     return PyLong_FromLong(0);
@@ -1205,7 +1203,7 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
         fd = devzero = open("/dev/zero", O_RDWR);
         if (devzero == -1) {
             Py_DECREF(m_obj);
-            PyErr_SetFromErrno(mmap_module_error);
+            PyErr_SetFromErrno(PyExc_OSError);
             return NULL;
         }
 #endif
@@ -1213,7 +1211,7 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
         m_obj->fd = dup(fd);
         if (m_obj->fd == -1) {
             Py_DECREF(m_obj);
-            PyErr_SetFromErrno(mmap_module_error);
+            PyErr_SetFromErrno(PyExc_OSError);
             return NULL;
         }
     }
@@ -1229,7 +1227,7 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
     if (m_obj->data == (char *)-1) {
         m_obj->data = NULL;
         Py_DECREF(m_obj);
-        PyErr_SetFromErrno(mmap_module_error);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     m_obj->access = (access_mode)access;
@@ -1310,12 +1308,12 @@ new_mmap_object(PyTypeObject *type, PyObject *args, PyObject *kwdict)
     if (fileno != -1 && fileno != 0) {
         /* Ensure that fileno is within the CRT's valid range */
         if (_PyVerify_fd(fileno) == 0) {
-            PyErr_SetFromErrno(mmap_module_error);
+            PyErr_SetFromErrno(PyExc_OSError);
             return NULL;
         }
         fh = (HANDLE)_get_osfhandle(fileno);
         if (fh==(HANDLE)-1) {
-            PyErr_SetFromErrno(mmap_module_error);
+            PyErr_SetFromErrno(PyExc_OSError);
             return NULL;
         }
         /* Win9x appears to need us seeked to zero */
@@ -1469,11 +1467,7 @@ PyInit_mmap(void)
     dict = PyModule_GetDict(module);
     if (!dict)
         return NULL;
-    mmap_module_error = PyErr_NewException("mmap.error",
-        PyExc_EnvironmentError , NULL);
-    if (mmap_module_error == NULL)
-        return NULL;
-    PyDict_SetItemString(dict, "error", mmap_module_error);
+    PyDict_SetItemString(dict, "error", PyExc_OSError);
     PyDict_SetItemString(dict, "mmap", (PyObject*) &mmap_object_type);
 #ifdef PROT_EXEC
     setint(dict, "PROT_EXEC", PROT_EXEC);

Modules/selectmodule.c

@@ -54,8 +54,6 @@ extern void bzero(void *, int);
 #  endif
 #endif
 
-static PyObject *SelectError;
-
 /* list of Python objects and their file descriptor */
 typedef struct {
     PyObject *obj;                           /* owned reference */
@@ -274,11 +272,11 @@ select_select(PyObject *self, PyObject *args)
 
 #ifdef MS_WINDOWS
     if (n == SOCKET_ERROR) {
-        PyErr_SetExcFromWindowsErr(SelectError, WSAGetLastError());
+        PyErr_SetExcFromWindowsErr(PyExc_OSError, WSAGetLastError());
     }
 #else
     if (n < 0) {
-        PyErr_SetFromErrno(SelectError);
+        PyErr_SetFromErrno(PyExc_OSError);
     }
 #endif
     else {
@@ -425,7 +423,7 @@ poll_modify(pollObject *self, PyObject *args)
         return NULL;
     if (PyDict_GetItem(self->dict, key) == NULL) {
         errno = ENOENT;
-        PyErr_SetFromErrno(PyExc_IOError);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     value = PyLong_FromLong(events);
@@ -524,7 +522,7 @@ poll_poll(pollObject *self, PyObject *args)
     Py_END_ALLOW_THREADS
 
     if (poll_result < 0) {
-        PyErr_SetFromErrno(SelectError);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
 
@@ -764,7 +762,7 @@ newPyEpoll_Object(PyTypeObject *type, int sizehint, SOCKET fd)
     }
     if (self->epfd < 0) {
         Py_DECREF(self);
-        PyErr_SetFromErrno(PyExc_IOError);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     return (PyObject *)self;
@@ -797,7 +795,7 @@ pyepoll_close(pyEpoll_Object *self)
 {
     errno = pyepoll_internal_close(self);
     if (errno < 0) {
-        PyErr_SetFromErrno(PyExc_IOError);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     Py_RETURN_NONE;
@@ -890,7 +888,7 @@ pyepoll_internal_ctl(int epfd, int op, PyObject *pfd, unsigned int events)
     }
 
     if (result < 0) {
-        PyErr_SetFromErrno(PyExc_IOError);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     Py_RETURN_NONE;
@@ -914,7 +912,7 @@ pyepoll_register(pyEpoll_Object *self, PyObject *args, PyObject *kwds)
 PyDoc_STRVAR(pyepoll_register_doc,
 "register(fd[, eventmask]) -> None\n\
 \n\
-Registers a new fd or raises an IOError if the fd is already registered.\n\
+Registers a new fd or raises an OSError if the fd is already registered.\n\
 fd is the target file descriptor of the operation.\n\
 events is a bit set composed of the various EPOLL constants; the default\n\
 is EPOLL_IN | EPOLL_OUT | EPOLL_PRI.\n\
@@ -1013,7 +1011,7 @@ pyepoll_poll(pyEpoll_Object *self, PyObject *args, PyObject *kwds)
     nfds = epoll_wait(self->epfd, evs, maxevents, timeout);
     Py_END_ALLOW_THREADS
     if (nfds < 0) {
-        PyErr_SetFromErrno(PyExc_IOError);
+        PyErr_SetFromErrno(PyExc_OSError);
         goto error;
     }
 
@@ -1404,7 +1402,7 @@ newKqueue_Object(PyTypeObject *type, SOCKET fd)
     }
     if (self->kqfd < 0) {
         Py_DECREF(self);
-        PyErr_SetFromErrno(PyExc_IOError);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     return (PyObject *)self;
@@ -1436,7 +1434,7 @@ kqueue_queue_close(kqueue_queue_Object *self)
 {
     errno = kqueue_queue_internal_close(self);
     if (errno < 0) {
-        PyErr_SetFromErrno(PyExc_IOError);
+        PyErr_SetFromErrno(PyExc_OSError);
         return NULL;
     }
     Py_RETURN_NONE;
@@ -1778,9 +1776,8 @@ PyInit_select(void)
     if (m == NULL)
         return NULL;
 
-    SelectError = PyErr_NewException("select.error", NULL, NULL);
-    Py_INCREF(SelectError);
-    PyModule_AddObject(m, "error", SelectError);
+    Py_INCREF(PyExc_OSError);
+    PyModule_AddObject(m, "error", PyExc_OSError);
 
 #ifdef PIPE_BUF
 #ifdef HAVE_BROKEN_PIPE_BUF

Python/errors.c

@@ -496,10 +496,11 @@ PyObject *PyErr_SetExcFromWindowsErrWithFilenameObject(
         return NULL;
     }
 
-    if (filenameObject != NULL)
-        v = Py_BuildValue("(iOO)", err, message, filenameObject);
-    else
-        v = Py_BuildValue("(iO)", err, message);
+    if (filenameObject == NULL)
+        filenameObject = Py_None;
+    /* This is the constructor signature for passing a Windows error code.
+       The POSIX translation will be figured out by the constructor. */
+    v = Py_BuildValue("(iOOi)", 0, message, filenameObject, err);
     Py_DECREF(message);
 
     if (v != NULL) {