Issue #10093: ResourceWarnings are now issued when files and sockets are
deallocated without explicit closing. These warnings are silenced by
default, except in pydebug mode.
diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index 74009e3..16b98d6 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -2,6 +2,7 @@
#define PY_SSIZE_T_CLEAN
#include "Python.h"
+#include "structmember.h"
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
@@ -55,6 +56,7 @@
unsigned int writable : 1;
signed int seekable : 2; /* -1 means unknown */
unsigned int closefd : 1;
+ unsigned int deallocating: 1;
PyObject *weakreflist;
PyObject *dict;
} fileio;
@@ -69,6 +71,26 @@
return ((fileio *)self)->fd < 0;
}
+/* Because this can call arbitrary code, it shouldn't be called when
+ the refcount is 0 (that is, not directly from tp_dealloc unless
+ the refcount has been temporarily re-incremented). */
+static PyObject *
+fileio_dealloc_warn(fileio *self, PyObject *source)
+{
+ if (self->fd >= 0 && self->closefd) {
+ PyObject *exc, *val, *tb;
+ PyErr_Fetch(&exc, &val, &tb);
+ if (PyErr_WarnFormat(PyExc_ResourceWarning, 1,
+ "unclosed file %R", source)) {
+ /* Spurious errors can appear at shutdown */
+ if (PyErr_ExceptionMatches(PyExc_Warning))
+ PyErr_WriteUnraisable((PyObject *) self);
+ }
+ PyErr_Restore(exc, val, tb);
+ }
+ Py_RETURN_NONE;
+}
+
static PyObject *
portable_lseek(int fd, PyObject *posobj, int whence);
@@ -110,6 +132,13 @@
self->fd = -1;
Py_RETURN_NONE;
}
+ if (self->deallocating) {
+ PyObject *r = fileio_dealloc_warn(self, (PyObject *) self);
+ if (r)
+ Py_DECREF(r);
+ else
+ PyErr_Clear();
+ }
errno = internal_close(self);
if (errno < 0)
return NULL;
@@ -399,6 +428,7 @@
static void
fileio_dealloc(fileio *self)
{
+ self->deallocating = 1;
if (_PyIOBase_finalize((PyObject *) self) < 0)
return;
_PyObject_GC_UNTRACK(self);
@@ -1008,6 +1038,7 @@
{"writable", (PyCFunction)fileio_writable, METH_NOARGS, writable_doc},
{"fileno", (PyCFunction)fileio_fileno, METH_NOARGS, fileno_doc},
{"isatty", (PyCFunction)fileio_isatty, METH_NOARGS, isatty_doc},
+ {"_dealloc_warn", (PyCFunction)fileio_dealloc_warn, METH_O, NULL},
{NULL, NULL} /* sentinel */
};