Issue #12797: Added custom opener parameter to builtin open() and FileIO.open().
diff --git a/Modules/_io/_iomodule.c b/Modules/_io/_iomodule.c
index 2ad002e..a8d3ed4 100644
--- a/Modules/_io/_iomodule.c
+++ b/Modules/_io/_iomodule.c
@@ -95,7 +95,7 @@
*/
PyDoc_STRVAR(open_doc,
"open(file, mode='r', buffering=-1, encoding=None,\n"
-" errors=None, newline=None, closefd=True) -> file object\n"
+" errors=None, newline=None, closefd=True, opener=None) -> file object\n"
"\n"
"Open file and return a stream. Raise IOError upon failure.\n"
"\n"
@@ -190,6 +190,12 @@
"when the file is closed. This does not work when a file name is given\n"
"and must be True in that case.\n"
"\n"
+"A custom opener can be used by passing a callable as *opener*. The\n"
+"underlying file descriptor for the file object is then obtained by\n"
+"calling *opener* with (*file*, *flags*). *opener* must return an open\n"
+"file descriptor (passing os.open as *opener* results in functionality\n"
+"similar to passing None).\n"
+"\n"
"open() returns a file object whose type depends on the mode, and\n"
"through which the standard file operations such as reading and writing\n"
"are performed. When open() is used to open a file in a text mode ('w',\n"
@@ -210,8 +216,8 @@
{
char *kwlist[] = {"file", "mode", "buffering",
"encoding", "errors", "newline",
- "closefd", NULL};
- PyObject *file;
+ "closefd", "opener", NULL};
+ PyObject *file, *opener = Py_None;
char *mode = "r";
int buffering = -1, closefd = 1;
char *encoding = NULL, *errors = NULL, *newline = NULL;
@@ -228,10 +234,10 @@
_Py_IDENTIFIER(isatty);
_Py_IDENTIFIER(fileno);
- if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|sizzzi:open", kwlist,
+ if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|sizzziO:open", kwlist,
&file, &mode, &buffering,
&encoding, &errors, &newline,
- &closefd)) {
+ &closefd, &opener)) {
return NULL;
}
@@ -331,7 +337,7 @@
/* Create the Raw file stream */
raw = PyObject_CallFunction((PyObject *)&PyFileIO_Type,
- "Osi", file, rawmode, closefd);
+ "OsiO", file, rawmode, closefd, opener);
if (raw == NULL)
return NULL;
diff --git a/Modules/_io/fileio.c b/Modules/_io/fileio.c
index acb0097..e3c0dd9 100644
--- a/Modules/_io/fileio.c
+++ b/Modules/_io/fileio.c
@@ -212,9 +212,9 @@
fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
{
fileio *self = (fileio *) oself;
- static char *kwlist[] = {"file", "mode", "closefd", NULL};
+ static char *kwlist[] = {"file", "mode", "closefd", "opener", NULL};
const char *name = NULL;
- PyObject *nameobj, *stringobj = NULL;
+ PyObject *nameobj, *stringobj = NULL, *opener = Py_None;
char *mode = "r";
char *s;
#ifdef MS_WINDOWS
@@ -233,8 +233,9 @@
return -1;
}
- if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|si:fileio",
- kwlist, &nameobj, &mode, &closefd))
+ if (!PyArg_ParseTupleAndKeywords(args, kwds, "O|siO:fileio",
+ kwlist, &nameobj, &mode, &closefd,
+ &opener))
return -1;
if (PyFloat_Check(nameobj)) {
@@ -363,15 +364,35 @@
goto error;
}
- Py_BEGIN_ALLOW_THREADS
errno = 0;
+ if (opener == Py_None) {
+ Py_BEGIN_ALLOW_THREADS
#ifdef MS_WINDOWS
- if (widename != NULL)
- self->fd = _wopen(widename, flags, 0666);
- else
+ if (widename != NULL)
+ self->fd = _wopen(widename, flags, 0666);
+ else
#endif
- self->fd = open(name, flags, 0666);
- Py_END_ALLOW_THREADS
+ self->fd = open(name, flags, 0666);
+ Py_END_ALLOW_THREADS
+ } else {
+ PyObject *fdobj = PyObject_CallFunction(
+ opener, "Oi", nameobj, flags);
+ if (fdobj == NULL)
+ goto error;
+ if (!PyLong_Check(fdobj)) {
+ Py_DECREF(fdobj);
+ PyErr_SetString(PyExc_TypeError,
+ "expected integer from opener");
+ goto error;
+ }
+
+ self->fd = PyLong_AsLong(fdobj);
+ Py_DECREF(fdobj);
+ if (self->fd == -1) {
+ goto error;
+ }
+ }
+
if (self->fd < 0) {
#ifdef MS_WINDOWS
if (widename != NULL)
@@ -1017,13 +1038,17 @@
PyDoc_STRVAR(fileio_doc,
-"file(name: str[, mode: str]) -> file IO object\n"
+"file(name: str[, mode: str][, opener: None]) -> file IO object\n"
"\n"
"Open a file. The mode can be 'r', 'w' or 'a' for reading (default),\n"
"writing or appending. The file will be created if it doesn't exist\n"
"when opened for writing or appending; it will be truncated when\n"
"opened for writing. Add a '+' to the mode to allow simultaneous\n"
-"reading and writing.");
+"reading and writing. A custom opener can be used by passing a\n"
+"callable as *opener*. The underlying file descriptor for the file\n"
+"object is then obtained by calling opener with (*name*, *flags*).\n"
+"*opener* must return an open file descriptor (passing os.open as\n"
+"*opener* results in functionality similar to passing None).");
PyDoc_STRVAR(read_doc,
"read(size: int) -> bytes. read at most size bytes, returned as bytes.\n"