implement a detach() method for BufferedIOBase and TextIOBase #5883
diff --git a/Modules/_io/bufferedio.c b/Modules/_io/bufferedio.c
index 3d175c7..2c65207 100644
--- a/Modules/_io/bufferedio.c
+++ b/Modules/_io/bufferedio.c
@@ -73,6 +73,18 @@
return NULL;
}
+PyDoc_STRVAR(BufferedIOBase_detach_doc,
+ "Disconnect this buffer from its underlying raw stream and return it.\n"
+ "\n"
+ "After the raw stream has been detached, the buffer is in an unusable\n"
+ "state.\n");
+
+static PyObject *
+BufferedIOBase_detach(PyObject *self)
+{
+ return BufferedIOBase_unsupported("detach");
+}
+
PyDoc_STRVAR(BufferedIOBase_read_doc,
"Read and return up to n bytes.\n"
"\n"
@@ -127,6 +139,7 @@
static PyMethodDef BufferedIOBase_methods[] = {
+ {"detach", (PyCFunction)BufferedIOBase_detach, METH_NOARGS, BufferedIOBase_detach_doc},
{"read", BufferedIOBase_read, METH_VARARGS, BufferedIOBase_read_doc},
{"read1", BufferedIOBase_read1, METH_VARARGS, BufferedIOBase_read1_doc},
{"readinto", BufferedIOBase_readinto, METH_VARARGS, NULL},
@@ -181,6 +194,7 @@
PyObject *raw;
int ok; /* Initialized? */
+ int detached;
int readable;
int writable;
@@ -260,15 +274,25 @@
#define CHECK_INITIALIZED(self) \
if (self->ok <= 0) { \
- PyErr_SetString(PyExc_ValueError, \
- "I/O operation on uninitialized object"); \
+ if (self->detached) { \
+ PyErr_SetString(PyExc_ValueError, \
+ "raw stream has been detached"); \
+ } else { \
+ PyErr_SetString(PyExc_ValueError, \
+ "I/O operation on uninitialized object"); \
+ } \
return NULL; \
}
#define CHECK_INITIALIZED_INT(self) \
if (self->ok <= 0) { \
- PyErr_SetString(PyExc_ValueError, \
- "I/O operation on uninitialized object"); \
+ if (self->detached) { \
+ PyErr_SetString(PyExc_ValueError, \
+ "raw stream has been detached"); \
+ } else { \
+ PyErr_SetString(PyExc_ValueError, \
+ "I/O operation on uninitialized object"); \
+ } \
return -1; \
}
@@ -430,6 +454,24 @@
return res;
}
+/* detach */
+
+static PyObject *
+BufferedIOMixin_detach(BufferedObject *self, PyObject *args)
+{
+ PyObject *raw, *res;
+ CHECK_INITIALIZED(self)
+ res = PyObject_CallMethodObjArgs((PyObject *)self, _PyIO_str_flush, NULL);
+ if (res == NULL)
+ return NULL;
+ Py_DECREF(res);
+ raw = self->raw;
+ self->raw = NULL;
+ self->detached = 1;
+ self->ok = 0;
+ return raw;
+}
+
/* Inquiries */
static PyObject *
@@ -1101,6 +1143,7 @@
PyObject *raw;
self->ok = 0;
+ self->detached = 0;
if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|n:BufferedReader", kwlist,
&raw, &buffer_size)) {
@@ -1387,6 +1430,7 @@
static PyMethodDef BufferedReader_methods[] = {
/* BufferedIOMixin methods */
+ {"detach", (PyCFunction)BufferedIOMixin_detach, METH_NOARGS},
{"flush", (PyCFunction)BufferedIOMixin_flush, METH_NOARGS},
{"close", (PyCFunction)BufferedIOMixin_close, METH_NOARGS},
{"seekable", (PyCFunction)BufferedIOMixin_seekable, METH_NOARGS},
@@ -1499,6 +1543,7 @@
PyObject *raw;
self->ok = 0;
+ self->detached = 0;
if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|nn:BufferedReader", kwlist,
&raw, &buffer_size, &max_buffer_size)) {
@@ -1745,6 +1790,7 @@
static PyMethodDef BufferedWriter_methods[] = {
/* BufferedIOMixin methods */
{"close", (PyCFunction)BufferedIOMixin_close, METH_NOARGS},
+ {"detach", (PyCFunction)BufferedIOMixin_detach, METH_NOARGS},
{"seekable", (PyCFunction)BufferedIOMixin_seekable, METH_NOARGS},
{"readable", (PyCFunction)BufferedIOMixin_readable, METH_NOARGS},
{"writable", (PyCFunction)BufferedIOMixin_writable, METH_NOARGS},
@@ -2089,6 +2135,7 @@
PyObject *raw;
self->ok = 0;
+ self->detached = 0;
if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|nn:BufferedReader", kwlist,
&raw, &buffer_size, &max_buffer_size)) {
@@ -2128,6 +2175,7 @@
static PyMethodDef BufferedRandom_methods[] = {
/* BufferedIOMixin methods */
{"close", (PyCFunction)BufferedIOMixin_close, METH_NOARGS},
+ {"detach", (PyCFunction)BufferedIOMixin_detach, METH_NOARGS},
{"seekable", (PyCFunction)BufferedIOMixin_seekable, METH_NOARGS},
{"readable", (PyCFunction)BufferedIOMixin_readable, METH_NOARGS},
{"writable", (PyCFunction)BufferedIOMixin_writable, METH_NOARGS},