Revert temporary commit in r79937

Lib/test/test_io.py

@@ -2394,47 +2394,6 @@ class MiscIOTest(unittest.TestCase):
         # baseline "io" module.
         self._check_abc_inheritance(io)
 
-    # Issue #5380: reading all available bytes from a pipe or a PTY when
-    # the other end has been closed.
-
-    def check_pipe_func(self, pipe_func, buffered):
-        master_fd, slave_fd = pipe_func()
-        # Simulate a subprocess writing some data to the
-        # slave end of the pipe, and then exiting.
-        data = b'TEST DATA'
-        try:
-            os.write(slave_fd, data)
-        finally:
-            os.close(slave_fd)
-        with self.open(master_fd, "rb", buffering=-1 if buffered else 0) as f:
-            # Request more data than available
-            gotdata = f.read(len(data) + 1)
-            self.assertEqual(gotdata, data)
-            # Trying to read again returns an empty string
-            self.assertEqual(b'', f.read())
-            self.assertEqual(b'', f.read(1))
-
-    def test_pipe_read_buffered(self):
-        if not hasattr(os, 'pipe'):
-            self.skipTest("os.pipe not available")
-        self.check_pipe_func(os.pipe, True)
-
-    def test_pipe_read_raw(self):
-        if not hasattr(os, 'pipe'):
-            self.skipTest("os.pipe not available")
-        self.check_pipe_func(os.pipe, False)
-
-    def test_openpty_read_buffered(self):
-        if not hasattr(os, 'openpty'):
-            self.skipTest("os.openpty not available")
-        self.check_pipe_func(os.openpty, True)
-
-    def test_openpty_read_raw(self):
-        if not hasattr(os, 'openpty'):
-            self.skipTest("os.openpty not available")
-        self.check_pipe_func(os.openpty, False)
-
-
 class CMiscIOTest(MiscIOTest):
     io = io
 

Lib/test/test_posix.py

@@ -280,29 +280,11 @@ class PosixTester(unittest.TestCase):
         if hasattr(posix, 'strerror'):
             self.assertTrue(posix.strerror(0))
 
-    def check_pipe_func(self, pipe_func):
-        master_fd, slave_fd = pipe_func()
-        try:
-            # Simulate a subprocess writing some data to the
-            # slave end of the pipe, and then exiting.
-            data = b'TEST DATA'
-            try:
-                os.write(slave_fd, data)
-            finally:
-                os.close(slave_fd)
-            # Request more data than available
-            gotdata = os.read(master_fd, len(data) + 1)
-            self.assertEqual(gotdata, data)
-        finally:
-            os.close(master_fd)
-
     def test_pipe(self):
         if hasattr(posix, 'pipe'):
-            self.check_pipe_func(posix.pipe)
-
-    def test_openpty(self):
-        if hasattr(posix, 'openpty'):
-            self.check_pipe_func(posix.openpty)
+            reader, writer = posix.pipe()
+            os.close(reader)
+            os.close(writer)
 
     def test_tempnam(self):
         if hasattr(posix, 'tempnam'):

Modules/_io/fileio.c

@@ -464,34 +464,6 @@ fileio_seekable(fileio *self)
 	return PyBool_FromLong((long) self->seekable);
 }
 
-static Py_ssize_t
-internal_read(int fd, void *buf, size_t count)
-{
-	Py_ssize_t n;
-
-	Py_BEGIN_ALLOW_THREADS
-	errno = 0;
-	n = read(fd, buf, count);
-#ifdef EIO
-	/* Issue #5380: when reading past the end of a pipe created by
-	   openpty(), EIO can be set.  Make it an EOF instead, so that
-	   the normal technique of testing for an empty string can be used.
-	 */
-	if (n == -1 && errno == EIO) {
-		if (isatty(fd)) {
-			n = 0;
-			errno = 0;
-		}
-		else {
-			/* isatty() set errno, restore its value */
-			errno = EIO;
-		}
-	}
-#endif
-	Py_END_ALLOW_THREADS
-	return n;
-}
-
 static PyObject *
 fileio_readinto(fileio *self, PyObject *args)
 {
@@ -506,9 +478,12 @@ fileio_readinto(fileio *self, PyObject *args)
 	if (!PyArg_ParseTuple(args, "w*", &pbuf))
 		return NULL;
 
-	if (_PyVerify_fd(self->fd))
-		n = internal_read(self->fd, pbuf.buf, pbuf.len);
-	else
+	if (_PyVerify_fd(self->fd)) {
+		Py_BEGIN_ALLOW_THREADS
+		errno = 0;
+		n = read(self->fd, pbuf.buf, pbuf.len);
+		Py_END_ALLOW_THREADS
+	} else
 		n = -1;
 	PyBuffer_Release(&pbuf);
 	if (n < 0) {
@@ -585,9 +560,12 @@ fileio_readall(fileio *self)
 				break;
 			}
 		}
-		n = internal_read(self->fd,
-				  PyBytes_AS_STRING(result) + total,
-				  newsize - total);
+		Py_BEGIN_ALLOW_THREADS
+		errno = 0;
+		n = read(self->fd,
+			 PyBytes_AS_STRING(result) + total,
+			 newsize - total);
+		Py_END_ALLOW_THREADS
 		if (n == 0)
 			break;
 		if (n < 0) {
@@ -639,9 +617,12 @@ fileio_read(fileio *self, PyObject *args)
 		return NULL;
 	ptr = PyBytes_AS_STRING(bytes);
 
-	if (_PyVerify_fd(self->fd))
-		n = internal_read(self->fd, ptr, size);
-	else
+	if (_PyVerify_fd(self->fd)) {
+		Py_BEGIN_ALLOW_THREADS
+		errno = 0;
+		n = read(self->fd, ptr, size);
+		Py_END_ALLOW_THREADS
+	} else
 		n = -1;
 
 	if (n < 0) {