Make it possible to instantiate a _FileIO() with an integer file descriptor

instead of a filename.
Add a 'closed' attribute.

diff --git a/Modules/_fileio.c b/Modules/_fileio.c
index adbf01b60caf621a2d1d0c3b84d6d84a4fe3e811..88ce2f1ae203872069b29556a73213cc4c8a276b 100644 (file)
--- a/Modules/_fileio.c
+++ b/Modules/_fileio.c
@@ -22,9 +22,8 @@
  *
  * Unanswered questions:
  *
- * - Add mode, name, and closed properties a la Python 2 file objects?
- * - Do we need a (*close)() in the struct like Python 2 file objects,
- *   for not-quite-ordinary-file objects?
+ * - Add mode and name properties a la Python 2 file objects?
+ * - Check for readable/writable before attempting to read/write?
  */
 
 #ifdef MS_WINDOWS
@@ -55,15 +54,16 @@ static PyObject *
 fileio_close(PyFileIOObject *self)
 {
        if (self->fd >= 0) {
+               int fd = self->fd;
+               self->fd = -1;
                Py_BEGIN_ALLOW_THREADS
                errno = 0;
-               close(self->fd);
+               close(fd);
                Py_END_ALLOW_THREADS
                if (errno < 0) {
                        PyErr_SetFromErrno(PyExc_IOError);
                        return NULL;
                }
-               self->fd = -1;
        }
 
        Py_RETURN_NONE;
@@ -123,7 +123,7 @@ static int
 fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
 {
        PyFileIOObject *self = (PyFileIOObject *) oself;
-       static char *kwlist[] = {"filename", "mode", NULL};
+       static char *kwlist[] = {"file", "mode", NULL};
        char *name = NULL;
        char *mode = "r";
         char *s;
@@ -131,6 +131,7 @@ fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
        int ret = 0;
        int rwa = 0, plus = 0, append = 0;
        int flags = 0;
+       int fd = -1;
 
        assert(PyFileIO_Check(oself));
        if (self->fd >= 0)
@@ -142,8 +143,20 @@ fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
                Py_DECREF(closeresult);
        }
 
+       if (PyArg_ParseTupleAndKeywords(args, kwds, "i|s:fileio",
+                                       kwlist, &fd, &mode)) {
+               if (fd < 0) {
+                       PyErr_SetString(PyExc_ValueError,
+                                       "Negative filedescriptor");
+                       return -1;
+               }
+       }
+       else {
+               PyErr_Clear();
+
 #ifdef Py_WIN_WIDE_FILENAMES
-       if (GetVersion() < 0x80000000) {    /* On NT, so wide API available */
+           if (GetVersion() < 0x80000000) {
+               /* On NT, so wide API available */
                PyObject *po;
                if (PyArg_ParseTupleAndKeywords(args, kwds, "U|s:fileio",
                                                kwlist, &po, &mode)) {
@@ -155,17 +168,18 @@ fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
                }
 
                PyErr_SetString(PyExc_NotImplementedError,
-                               "Windows wide filenames are not yet supported");
+                       "Windows wide filenames are not yet supported");
                goto error;
-       }
+           }
 #endif
 
-       if (!wideargument) {
+           if (!wideargument) {
                if (!PyArg_ParseTupleAndKeywords(args, kwds, "et|s:fileio",
                                                 kwlist,
                                                 Py_FileSystemDefaultEncoding,
                                                 &name, &mode))
                        goto error;
+           }
        }
 
        self->readable = self->writable = 0;
@@ -224,13 +238,19 @@ fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
        flags |= O_BINARY;
 #endif
 
-       Py_BEGIN_ALLOW_THREADS
-       errno = 0;
-       self->fd = open(name, flags, 0666);
-       Py_END_ALLOW_THREADS
-       if (self->fd < 0 || dircheck(self) < 0) {
-               PyErr_SetFromErrnoWithFilename(PyExc_IOError, name);
-               goto error;
+       if (fd >= 0) {
+               self->fd = fd;
+               /* XXX Should we set self->own_fd = 0 ??? */
+       }
+       else {
+               Py_BEGIN_ALLOW_THREADS
+               errno = 0;
+               self->fd = open(name, flags, 0666);
+               Py_END_ALLOW_THREADS
+               if (self->fd < 0 || dircheck(self) < 0) {
+                       PyErr_SetFromErrnoWithFilename(PyExc_IOError, name);
+                       goto error;
+               }
        }
 
        goto done;
@@ -652,6 +672,18 @@ static PyMethodDef fileio_methods[] = {
        {NULL,       NULL}             /* sentinel */
 };
 
+/* 'closed' is an attribute for backwards compatibility reasons. */
+static PyObject *
+get_closed(PyFileIOObject *f, void *closure)
+{
+       return PyBool_FromLong((long)(f->fd < 0));
+}
+
+static PyGetSetDef fileio_getsetlist[] = {
+       {"closed", (getter)get_closed, NULL, "True if the file is closed"},
+       {0},
+};
+
 PyTypeObject PyFileIO_Type = {
        PyObject_HEAD_INIT(&PyType_Type)
        0,
@@ -683,7 +715,7 @@ PyTypeObject PyFileIO_Type = {
        0,                                      /* tp_iternext */
        fileio_methods,                         /* tp_methods */
        0,                                      /* tp_members */
-       0,                                      /* tp_getset */
+       fileio_getsetlist,                      /* tp_getset */
        0,                                      /* tp_base */
        0,                                      /* tp_dict */
        0,                                      /* tp_descr_get */