Issue #23099: Closing io.BytesIO with exported buffer is rejected now to
prevent corrupting exported buffer.
diff --git a/Doc/library/io.rst b/Doc/library/io.rst
index b8dc688..3adf6e9 100644
--- a/Doc/library/io.rst
+++ b/Doc/library/io.rst
@@ -563,7 +563,8 @@
.. class:: BytesIO([initial_bytes])
A stream implementation using an in-memory bytes buffer. It inherits
- :class:`BufferedIOBase`.
+ :class:`BufferedIOBase`. The buffer is discarded when the
+ :meth:`~IOBase.close` method is called.
The argument *initial_bytes* contains optional initial :class:`bytes` data.
@@ -584,7 +585,7 @@
.. note::
As long as the view exists, the :class:`BytesIO` object cannot be
- resized.
+ resized or closed.
.. versionadded:: 3.2
@@ -592,6 +593,7 @@
Return :class:`bytes` containing the entire contents of the buffer.
+
.. method:: read1()
In :class:`BytesIO`, this is the same as :meth:`read`.
@@ -858,7 +860,8 @@
.. class:: StringIO(initial_value='', newline='\\n')
- An in-memory stream for text I/O.
+ An in-memory stream for text I/O. The text buffer is discarded when the
+ :meth:`~IOBase.close` method is called.
The initial value of the buffer (an empty string by default) can be set by
providing *initial_value*. The *newline* argument works like that of
@@ -870,9 +873,7 @@
.. method:: getvalue()
- Return a ``str`` containing the entire contents of the buffer at any
- time before the :class:`StringIO` object's :meth:`close` method is
- called.
+ Return a ``str`` containing the entire contents of the buffer.
Example usage::
diff --git a/Lib/_pyio.py b/Lib/_pyio.py
index 01683f8..577b600 100644
--- a/Lib/_pyio.py
+++ b/Lib/_pyio.py
@@ -833,8 +833,14 @@
def getbuffer(self):
"""Return a readable and writable view of the buffer.
"""
+ if self.closed:
+ raise ValueError("getbuffer on closed file")
return memoryview(self._buffer)
+ def close(self):
+ self._buffer.clear()
+ super().close()
+
def read(self, size=None):
if self.closed:
raise ValueError("read from closed file")
diff --git a/Lib/test/test_memoryio.py b/Lib/test/test_memoryio.py
index 7cae8b2..9a2461d 100644
--- a/Lib/test/test_memoryio.py
+++ b/Lib/test/test_memoryio.py
@@ -398,14 +398,19 @@
# raises a BufferError.
self.assertRaises(BufferError, memio.write, b'x' * 100)
self.assertRaises(BufferError, memio.truncate)
+ self.assertRaises(BufferError, memio.close)
+ self.assertFalse(memio.closed)
# Mutating the buffer updates the BytesIO
buf[3:6] = b"abc"
self.assertEqual(bytes(buf), b"123abc7890")
self.assertEqual(memio.getvalue(), b"123abc7890")
- # After the buffer gets released, we can resize the BytesIO again
+ # After the buffer gets released, we can resize and close the BytesIO
+ # again
del buf
support.gc_collect()
memio.truncate()
+ memio.close()
+ self.assertRaises(ValueError, memio.getbuffer)
class PyBytesIOTest(MemoryTestMixin, MemorySeekTestMixin,
diff --git a/Misc/NEWS b/Misc/NEWS
index 976368e..6d58e8b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -56,6 +56,9 @@
Library
-------
+- Issue #23099: Closing io.BytesIO with exported buffer is rejected now to
+ prevent corrupting exported buffer.
+
- Issue #23363: Fix possible overflow in itertools.permutations.
- Issue #23364: Fix possible overflow in itertools.product.
diff --git a/Modules/_io/bytesio.c b/Modules/_io/bytesio.c
index 57c2073..1537d97 100644
--- a/Modules/_io/bytesio.c
+++ b/Modules/_io/bytesio.c
@@ -657,6 +657,7 @@
static PyObject *
bytesio_close(bytesio *self)
{
+ CHECK_EXPORTS(self);
if (self->buf != NULL) {
PyMem_Free(self->buf);
self->buf = NULL;