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.

1 files changed, 30 insertions, 1 deletions

diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index 615e644..3045169 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -197,6 +197,7 @@ typedef struct {
     int detached;
     int readable;
     int writable;
+    int deallocating;
     
     /* True if this is a vanilla Buffered object (rather than a user derived
        class) *and* the raw stream is a vanilla FileIO object. */
@@ -342,6 +343,7 @@ typedef struct {
 static void
 buffered_dealloc(buffered *self)
 {
+    self->deallocating = 1;
     if (self->ok && _PyIOBase_finalize((PyObject *) self) < 0)
         return;
     _PyObject_GC_UNTRACK(self);
@@ -382,6 +384,23 @@ buffered_clear(buffered *self)
     return 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). */
+PyObject *
+buffered_dealloc_warn(buffered *self, PyObject *source)
+{
+    if (self->ok && self->raw) {
+        PyObject *r;
+        r = PyObject_CallMethod(self->raw, "_dealloc_warn", "O", source);
+        if (r)
+            Py_DECREF(r);
+        else
+            PyErr_Clear();
+    }
+    Py_RETURN_NONE;
+}
+
 /*
  * _BufferedIOMixin methods
  * This is not a class, just a collection of methods that will be reused
@@ -435,6 +454,14 @@ buffered_close(buffered *self, PyObject *args)
         Py_INCREF(res);
         goto end;
     }
+
+    if (self->deallocating) {
+        PyObject *r = buffered_dealloc_warn(self, (PyObject *) self);
+        if (r)
+            Py_DECREF(r);
+        else
+            PyErr_Clear();
+    }
     /* flush() will most probably re-take the lock, so drop it first */
     LEAVE_BUFFERED(self)
     res = PyObject_CallMethodObjArgs((PyObject *)self, _PyIO_str_flush, NULL);
@@ -1461,6 +1488,7 @@ static PyMethodDef bufferedreader_methods[] = {
     {"writable", (PyCFunction)buffered_writable, METH_NOARGS},
     {"fileno", (PyCFunction)buffered_fileno, METH_NOARGS},
     {"isatty", (PyCFunction)buffered_isatty, METH_NOARGS},
+    {"_dealloc_warn", (PyCFunction)buffered_dealloc_warn, METH_O},
 
     {"read", (PyCFunction)buffered_read, METH_VARARGS},
     {"peek", (PyCFunction)buffered_peek, METH_VARARGS},
@@ -1843,6 +1871,7 @@ static PyMethodDef bufferedwriter_methods[] = {
     {"writable", (PyCFunction)buffered_writable, METH_NOARGS},
     {"fileno", (PyCFunction)buffered_fileno, METH_NOARGS},
     {"isatty", (PyCFunction)buffered_isatty, METH_NOARGS},
+    {"_dealloc_warn", (PyCFunction)buffered_dealloc_warn, METH_O},
 
     {"write", (PyCFunction)bufferedwriter_write, METH_VARARGS},
     {"truncate", (PyCFunction)buffered_truncate, METH_VARARGS},
@@ -2227,6 +2256,7 @@ static PyMethodDef bufferedrandom_methods[] = {
     {"writable", (PyCFunction)buffered_writable, METH_NOARGS},
     {"fileno", (PyCFunction)buffered_fileno, METH_NOARGS},
     {"isatty", (PyCFunction)buffered_isatty, METH_NOARGS},
+    {"_dealloc_warn", (PyCFunction)buffered_dealloc_warn, METH_O},
 
     {"flush", (PyCFunction)buffered_flush, METH_NOARGS},
 
@@ -2296,4 +2326,3 @@ PyTypeObject PyBufferedRandom_Type = {
     0,                          /* tp_alloc */
     PyType_GenericNew,          /* tp_new */
 };
-