/Modules/_fileio.c

  1/* Author: Daniel Stutzbach */
  2
  3#define PY_SSIZE_T_CLEAN
  4#include "Python.h"
  5#include <sys/types.h>
  6#include <sys/stat.h>
  7#include <fcntl.h>
  8#include <stddef.h> /* For offsetof */
  9
 10/*
 11 * Known likely problems:
 12 *
 13 * - Files larger then 2**32-1
 14 * - Files with unicode filenames
 15 * - Passing numbers greater than 2**32-1 when an integer is expected
 16 * - Making it work on Windows and other oddball platforms
 17 *
 18 * To Do:
 19 *
 20 * - autoconfify header file inclusion
 21 */
 22
 23#ifdef MS_WINDOWS
 24/* can simulate truncate with Win32 API functions; see file_truncate */
 25#define HAVE_FTRUNCATE
 26#define WIN32_LEAN_AND_MEAN
 27#include <windows.h>
 28#endif
 29
 30typedef struct {
 31	PyObject_HEAD
 32	int fd;
 33	unsigned int readable : 1;
 34	unsigned int writable : 1;
 35	signed int seekable : 2; /* -1 means unknown */
 36	signed int closefd : 1;
 37	PyObject *weakreflist;
 38} PyFileIOObject;
 39
 40PyTypeObject PyFileIO_Type;
 41
 42#define PyFileIO_Check(op) (PyObject_TypeCheck((op), &PyFileIO_Type))
 43
 44static PyObject *
 45portable_lseek(int fd, PyObject *posobj, int whence);
 46
 47/* Returns 0 on success, errno (which is < 0) on failure. */
 48static int
 49internal_close(PyFileIOObject *self)
 50{
 51	int save_errno = 0;
 52	if (self->fd >= 0) {
 53		int fd = self->fd;
 54		self->fd = -1;
 55		Py_BEGIN_ALLOW_THREADS
 56		if (close(fd) < 0)
 57			save_errno = errno;
 58		Py_END_ALLOW_THREADS
 59	}
 60	return save_errno;
 61}
 62
 63static PyObject *
 64fileio_close(PyFileIOObject *self)
 65{
 66	if (!self->closefd) {
 67		self->fd = -1;
 68		Py_RETURN_NONE;
 69	}
 70	errno = internal_close(self);
 71	if (errno < 0) {
 72		PyErr_SetFromErrno(PyExc_IOError);
 73		return NULL;
 74	}
 75
 76	Py_RETURN_NONE;
 77}
 78
 79static PyObject *
 80fileio_new(PyTypeObject *type, PyObject *args, PyObject *kews)
 81{
 82	PyFileIOObject *self;
 83
 84	assert(type != NULL && type->tp_alloc != NULL);
 85
 86	self = (PyFileIOObject *) type->tp_alloc(type, 0);
 87	if (self != NULL) {
 88		self->fd = -1;
 89		self->readable = 0;
 90		self->writable = 0;
 91		self->seekable = -1;
 92		self->closefd = 1;
 93		self->weakreflist = NULL;
 94	}
 95
 96	return (PyObject *) self;
 97}
 98
 99/* On Unix, open will succeed for directories.
100   In Python, there should be no file objects referring to
101   directories, so we need a check.  */
102
103static int
104dircheck(PyFileIOObject* self, char *name)
105{
106#if defined(HAVE_FSTAT) && defined(S_IFDIR) && defined(EISDIR)
107	struct stat buf;
108	if (self->fd < 0)
109		return 0;
110	if (fstat(self->fd, &buf) == 0 && S_ISDIR(buf.st_mode)) {
111		char *msg = strerror(EISDIR);
112		PyObject *exc;
113		internal_close(self);
114
115		exc = PyObject_CallFunction(PyExc_IOError, "(iss)",
116					    EISDIR, msg, name);
117		PyErr_SetObject(PyExc_IOError, exc);
118		Py_XDECREF(exc);
119		return -1;
120	}
121#endif
122	return 0;
123}
124
125static int
126check_fd(int fd)
127{
128#if defined(HAVE_FSTAT)
129	struct stat buf;
130	if (fstat(fd, &buf) < 0 && errno == EBADF) {
131		PyObject *exc;
132		char *msg = strerror(EBADF);
133		exc = PyObject_CallFunction(PyExc_OSError, "(is)",
134					    EBADF, msg);
135		PyErr_SetObject(PyExc_OSError, exc);
136		Py_XDECREF(exc);
137		return -1;
138	}
139#endif
140	return 0;
141}
142
143
144static int
145fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
146{
147	PyFileIOObject *self = (PyFileIOObject *) oself;
148	static char *kwlist[] = {"file", "mode", "closefd", NULL};
149	char *name = NULL;
150	char *mode = "r";
151	char *s;
152#ifdef MS_WINDOWS
153	Py_UNICODE *widename = NULL;
154#endif
155	int ret = 0;
156	int rwa = 0, plus = 0, append = 0;
157	int flags = 0;
158	int fd = -1;
159	int closefd = 1;
160
161	assert(PyFileIO_Check(oself));
162	if (self->fd >= 0) {
163		/* Have to close the existing file first. */
164		if (internal_close(self) < 0)
165			return -1;
166	}
167
168	if (PyArg_ParseTupleAndKeywords(args, kwds, "i|si:fileio",
169					kwlist, &fd, &mode, &closefd)) {
170		if (fd < 0) {
171			PyErr_SetString(PyExc_ValueError,
172					"Negative filedescriptor");
173			return -1;
174		}
175		if (check_fd(fd))
176			return -1;
177	}
178	else {
179		PyErr_Clear();
180
181#ifdef Py_WIN_WIDE_FILENAMES
182	    if (GetVersion() < 0x80000000) {
183		/* On NT, so wide API available */
184		PyObject *po;
185		if (PyArg_ParseTupleAndKeywords(args, kwds, "U|si:fileio",
186						kwlist, &po, &mode, &closefd)
187						) {
188			widename = PyUnicode_AS_UNICODE(po);
189		} else {
190			/* Drop the argument parsing error as narrow
191			   strings are also valid. */
192			PyErr_Clear();
193		}
194	    }
195	    if (widename == NULL)
196#endif
197	    {
198		if (!PyArg_ParseTupleAndKeywords(args, kwds, "et|si:fileio",
199						 kwlist,
200						 Py_FileSystemDefaultEncoding,
201						 &name, &mode, &closefd))
202			return -1;
203	    }
204	}
205
206	s = mode;
207	while (*s) {
208		switch (*s++) {
209		case 'r':
210			if (rwa) {
211			bad_mode:
212				PyErr_SetString(PyExc_ValueError,
213						"Must have exactly one of read/write/append mode");
214				goto error;
215			}
216			rwa = 1;
217			self->readable = 1;
218			break;
219		case 'w':
220			if (rwa)
221				goto bad_mode;
222			rwa = 1;
223			self->writable = 1;
224			flags |= O_CREAT | O_TRUNC;
225			break;
226		case 'a':
227			if (rwa)
228				goto bad_mode;
229			rwa = 1;
230			self->writable = 1;
231			flags |= O_CREAT;
232			append = 1;
233			break;
234		case 'b':
235			break;
236		case '+':
237			if (plus)
238				goto bad_mode;
239			self->readable = self->writable = 1;
240			plus = 1;
241			break;
242		default:
243			PyErr_Format(PyExc_ValueError,
244				     "invalid mode: %.200s", mode);
245			goto error;
246		}
247	}
248
249	if (!rwa)
250		goto bad_mode;
251
252	if (self->readable && self->writable)
253		flags |= O_RDWR;
254	else if (self->readable)
255		flags |= O_RDONLY;
256	else
257		flags |= O_WRONLY;
258
259#ifdef O_BINARY
260	flags |= O_BINARY;
261#endif
262
263#ifdef O_APPEND
264	if (append)
265		flags |= O_APPEND;
266#endif
267
268	if (fd >= 0) {
269		self->fd = fd;
270		self->closefd = closefd;
271	}
272	else {
273		self->closefd = 1;
274		if (!closefd) {
275			PyErr_SetString(PyExc_ValueError,
276                            "Cannot use closefd=False with file name");
277			goto error;
278		}
279
280		Py_BEGIN_ALLOW_THREADS
281		errno = 0;
282#ifdef MS_WINDOWS
283		if (widename != NULL)
284			self->fd = _wopen(widename, flags, 0666);
285		else
286#endif
287			self->fd = open(name, flags, 0666);
288		Py_END_ALLOW_THREADS
289		if (self->fd < 0) {
290#ifdef MS_WINDOWS
291			if (widename != NULL)
292				PyErr_SetFromErrnoWithUnicodeFilename(PyExc_IOError, widename);
293			else
294#endif
295				PyErr_SetFromErrnoWithFilename(PyExc_IOError, name);
296			goto error;
297		}
298		if(dircheck(self, name) < 0)
299			goto error;
300	}
301
302	if (append) {
303		/* For consistent behaviour, we explicitly seek to the
304		   end of file (otherwise, it might be done only on the
305		   first write()). */
306		PyObject *pos = portable_lseek(self->fd, NULL, 2);
307		if (pos == NULL)
308			goto error;
309		Py_DECREF(pos);
310	}
311
312	goto done;
313
314 error:
315	ret = -1;
316
317 done:
318	PyMem_Free(name);
319	return ret;
320}
321
322static void
323fileio_dealloc(PyFileIOObject *self)
324{
325	if (self->weakreflist != NULL)
326		PyObject_ClearWeakRefs((PyObject *) self);
327
328	if (self->fd >= 0 && self->closefd) {
329		errno = internal_close(self);
330		if (errno < 0) {
331			PySys_WriteStderr("close failed: [Errno %d] %s\n",
332                                          errno, strerror(errno));
333		}
334	}
335
336	Py_TYPE(self)->tp_free((PyObject *)self);
337}
338
339static PyObject *
340err_closed(void)
341{
342	PyErr_SetString(PyExc_ValueError, "I/O operation on closed file");
343	return NULL;
344}
345
346static PyObject *
347err_mode(char *action)
348{
349	PyErr_Format(PyExc_ValueError, "File not open for %s", action);
350	return NULL;
351}
352
353static PyObject *
354fileio_fileno(PyFileIOObject *self)
355{
356	if (self->fd < 0)
357		return err_closed();
358	return PyInt_FromLong((long) self->fd);
359}
360
361static PyObject *
362fileio_readable(PyFileIOObject *self)
363{
364	if (self->fd < 0)
365		return err_closed();
366	return PyBool_FromLong((long) self->readable);
367}
368
369static PyObject *
370fileio_writable(PyFileIOObject *self)
371{
372	if (self->fd < 0)
373		return err_closed();
374	return PyBool_FromLong((long) self->writable);
375}
376
377static PyObject *
378fileio_seekable(PyFileIOObject *self)
379{
380	if (self->fd < 0)
381		return err_closed();
382	if (self->seekable < 0) {
383		int ret;
384		Py_BEGIN_ALLOW_THREADS
385		ret = lseek(self->fd, 0, SEEK_CUR);
386		Py_END_ALLOW_THREADS
387		if (ret < 0)
388			self->seekable = 0;
389		else
390			self->seekable = 1;
391	}
392	return PyBool_FromLong((long) self->seekable);
393}
394
395static PyObject *
396fileio_readinto(PyFileIOObject *self, PyObject *args)
397{
398	Py_buffer pbuf;
399	Py_ssize_t n;
400
401	if (self->fd < 0)
402		return err_closed();
403	if (!self->readable)
404		return err_mode("reading");
405
406	if (!PyArg_ParseTuple(args, "w*", &pbuf))
407		return NULL;
408
409	Py_BEGIN_ALLOW_THREADS
410	errno = 0;
411	n = read(self->fd, pbuf.buf, pbuf.len);
412	Py_END_ALLOW_THREADS
413	PyBuffer_Release(&pbuf);
414	if (n < 0) {
415		if (errno == EAGAIN)
416			Py_RETURN_NONE;
417		PyErr_SetFromErrno(PyExc_IOError);
418		return NULL;
419	}
420
421	return PyLong_FromSsize_t(n);
422}
423
424#define DEFAULT_BUFFER_SIZE (8*1024)
425
426static PyObject *
427fileio_readall(PyFileIOObject *self)
428{
429	PyObject *result;
430	Py_ssize_t total = 0;
431	int n;
432
433	result = PyString_FromStringAndSize(NULL, DEFAULT_BUFFER_SIZE);
434	if (result == NULL)
435		return NULL;
436
437	while (1) {
438		Py_ssize_t newsize = total + DEFAULT_BUFFER_SIZE;
439		if (PyString_GET_SIZE(result) < newsize) {
440			if (_PyString_Resize(&result, newsize) < 0) {
441				if (total == 0) {
442					Py_DECREF(result);
443					return NULL;
444				}
445				PyErr_Clear();
446				break;
447			}
448		}
449		Py_BEGIN_ALLOW_THREADS
450		errno = 0;
451		n = read(self->fd,
452			 PyString_AS_STRING(result) + total,
453			 newsize - total);
454		Py_END_ALLOW_THREADS
455		if (n == 0)
456			break;
457		if (n < 0) {
458			if (total > 0)
459				break;
460			if (errno == EAGAIN) {
461				Py_DECREF(result);
462				Py_RETURN_NONE;
463			}
464			Py_DECREF(result);
465			PyErr_SetFromErrno(PyExc_IOError);
466			return NULL;
467		}
468		total += n;
469	}
470
471	if (PyString_GET_SIZE(result) > total) {
472		if (_PyString_Resize(&result, total) < 0) {
473			/* This should never happen, but just in case */
474			Py_DECREF(result);
475			return NULL;
476		}
477	}
478	return result;
479}
480
481static PyObject *
482fileio_read(PyFileIOObject *self, PyObject *args)
483{
484	char *ptr;
485	Py_ssize_t n;
486	Py_ssize_t size = -1;
487	PyObject *bytes;
488
489	if (self->fd < 0)
490		return err_closed();
491	if (!self->readable)
492		return err_mode("reading");
493
494	if (!PyArg_ParseTuple(args, "|n", &size))
495		return NULL;
496
497        if (size < 0) {
498		return fileio_readall(self);
499	}
500
501	bytes = PyString_FromStringAndSize(NULL, size);
502	if (bytes == NULL)
503		return NULL;
504	ptr = PyString_AS_STRING(bytes);
505
506	Py_BEGIN_ALLOW_THREADS
507	errno = 0;
508	n = read(self->fd, ptr, size);
509	Py_END_ALLOW_THREADS
510
511	if (n < 0) {
512		if (errno == EAGAIN)
513			Py_RETURN_NONE;
514		PyErr_SetFromErrno(PyExc_IOError);
515		return NULL;
516	}
517
518	if (n != size) {
519		if (_PyString_Resize(&bytes, n) < 0) {
520			Py_DECREF(bytes);
521			return NULL;
522		}
523	}
524
525	return (PyObject *) bytes;
526}
527
528static PyObject *
529fileio_write(PyFileIOObject *self, PyObject *args)
530{
531	Py_buffer pbuf;
532	Py_ssize_t n;
533
534	if (self->fd < 0)
535		return err_closed();
536	if (!self->writable)
537		return err_mode("writing");
538
539	if (!PyArg_ParseTuple(args, "s*", &pbuf))
540		return NULL;
541
542	Py_BEGIN_ALLOW_THREADS
543	errno = 0;
544	n = write(self->fd, pbuf.buf, pbuf.len);
545	Py_END_ALLOW_THREADS
546
547	PyBuffer_Release(&pbuf);
548
549	if (n < 0) {
550		if (errno == EAGAIN)
551			Py_RETURN_NONE;
552		PyErr_SetFromErrno(PyExc_IOError);
553		return NULL;
554	}
555
556	return PyLong_FromSsize_t(n);
557}
558
559/* XXX Windows support below is likely incomplete */
560
561#if defined(MS_WIN64) || defined(MS_WINDOWS)
562typedef PY_LONG_LONG Py_off_t;
563#else
564typedef off_t Py_off_t;
565#endif
566
567/* Cribbed from posix_lseek() */
568static PyObject *
569portable_lseek(int fd, PyObject *posobj, int whence)
570{
571	Py_off_t pos, res;
572
573#ifdef SEEK_SET
574	/* Turn 0, 1, 2 into SEEK_{SET,CUR,END} */
575	switch (whence) {
576#if SEEK_SET != 0
577	case 0: whence = SEEK_SET; break;
578#endif
579#if SEEK_CUR != 1
580	case 1: whence = SEEK_CUR; break;
581#endif
582#if SEEL_END != 2
583	case 2: whence = SEEK_END; break;
584#endif
585	}
586#endif /* SEEK_SET */
587
588	if (posobj == NULL)
589		pos = 0;
590	else {
591		if(PyFloat_Check(posobj)) {
592			PyErr_SetString(PyExc_TypeError, "an integer is required");
593			return NULL;
594		}
595#if defined(HAVE_LARGEFILE_SUPPORT)
596		pos = PyLong_AsLongLong(posobj);
597#else
598		pos = PyLong_AsLong(posobj);
599#endif
600		if (PyErr_Occurred())
601			return NULL;
602	}
603
604	Py_BEGIN_ALLOW_THREADS
605#if defined(MS_WIN64) || defined(MS_WINDOWS)
606	res = _lseeki64(fd, pos, whence);
607#else
608	res = lseek(fd, pos, whence);
609#endif
610	Py_END_ALLOW_THREADS
611	if (res < 0)
612		return PyErr_SetFromErrno(PyExc_IOError);
613
614#if defined(HAVE_LARGEFILE_SUPPORT)
615	return PyLong_FromLongLong(res);
616#else
617	return PyLong_FromLong(res);
618#endif
619}
620
621static PyObject *
622fileio_seek(PyFileIOObject *self, PyObject *args)
623{
624	PyObject *posobj;
625	int whence = 0;
626
627	if (self->fd < 0)
628		return err_closed();
629
630	if (!PyArg_ParseTuple(args, "O|i", &posobj, &whence))
631		return NULL;
632
633	return portable_lseek(self->fd, posobj, whence);
634}
635
636static PyObject *
637fileio_tell(PyFileIOObject *self, PyObject *args)
638{
639	if (self->fd < 0)
640		return err_closed();
641
642	return portable_lseek(self->fd, NULL, 1);
643}
644
645#ifdef HAVE_FTRUNCATE
646static PyObject *
647fileio_truncate(PyFileIOObject *self, PyObject *args)
648{
649	PyObject *posobj = NULL;
650	Py_off_t pos;
651	int ret;
652	int fd;
653
654	fd = self->fd;
655	if (fd < 0)
656		return err_closed();
657	if (!self->writable)
658		return err_mode("writing");
659
660	if (!PyArg_ParseTuple(args, "|O", &posobj))
661		return NULL;
662
663	if (posobj == Py_None || posobj == NULL) {
664		/* Get the current position. */
665                posobj = portable_lseek(fd, NULL, 1);
666                if (posobj == NULL)
667			return NULL;
668        }
669        else {
670		/* Move to the position to be truncated. */
671                posobj = portable_lseek(fd, posobj, 0);
672        }
673
674#if defined(HAVE_LARGEFILE_SUPPORT)
675	pos = PyLong_AsLongLong(posobj);
676#else
677	pos = PyLong_AsLong(posobj);
678#endif
679	if (PyErr_Occurred())
680		return NULL;
681
682#ifdef MS_WINDOWS
683	/* MS _chsize doesn't work if newsize doesn't fit in 32 bits,
684	   so don't even try using it. */
685	{
686		HANDLE hFile;
687
688		/* Truncate.  Note that this may grow the file! */
689		Py_BEGIN_ALLOW_THREADS
690		errno = 0;
691		hFile = (HANDLE)_get_osfhandle(fd);
692		ret = hFile == (HANDLE)-1;
693		if (ret == 0) {
694			ret = SetEndOfFile(hFile) == 0;
695			if (ret)
696				errno = EACCES;
697		}
698		Py_END_ALLOW_THREADS
699	}
700#else
701	Py_BEGIN_ALLOW_THREADS
702	errno = 0;
703	ret = ftruncate(fd, pos);
704	Py_END_ALLOW_THREADS
705#endif /* !MS_WINDOWS */
706
707	if (ret != 0) {
708		PyErr_SetFromErrno(PyExc_IOError);
709		return NULL;
710	}
711
712	return posobj;
713}
714#endif
715
716static char *
717mode_string(PyFileIOObject *self)
718{
719	if (self->readable) {
720		if (self->writable)
721			return "rb+";
722		else
723			return "rb";
724	}
725	else
726		return "wb";
727}
728
729static PyObject *
730fileio_repr(PyFileIOObject *self)
731{
732        if (self->fd < 0)
733		return PyString_FromFormat("_fileio._FileIO(-1)");
734
735	return PyString_FromFormat("_fileio._FileIO(%d, '%s')",
736				   self->fd, mode_string(self));
737}
738
739static PyObject *
740fileio_isatty(PyFileIOObject *self)
741{
742	long res;
743
744	if (self->fd < 0)
745		return err_closed();
746	Py_BEGIN_ALLOW_THREADS
747	res = isatty(self->fd);
748	Py_END_ALLOW_THREADS
749	return PyBool_FromLong(res);
750}
751
752
753PyDoc_STRVAR(fileio_doc,
754"file(name: str[, mode: str]) -> file IO object\n"
755"\n"
756"Open a file.  The mode can be 'r', 'w' or 'a' for reading (default),\n"
757"writing or appending.	The file will be created if it doesn't exist\n"
758"when opened for writing or appending; it will be truncated when\n"
759"opened for writing.  Add a '+' to the mode to allow simultaneous\n"
760"reading and writing.");
761
762PyDoc_STRVAR(read_doc,
763"read(size: int) -> bytes.  read at most size bytes, returned as bytes.\n"
764"\n"
765"Only makes one system call, so less data may be returned than requested\n"
766"In non-blocking mode, returns None if no data is available.\n"
767"On end-of-file, returns ''.");
768
769PyDoc_STRVAR(readall_doc,
770"readall() -> bytes.  read all data from the file, returned as bytes.\n"
771"\n"
772"In non-blocking mode, returns as much as is immediately available,\n"
773"or None if no data is available.  On end-of-file, returns ''.");
774
775PyDoc_STRVAR(write_doc,
776"write(b: bytes) -> int.  Write bytes b to file, return number written.\n"
777"\n"
778"Only makes one system call, so not all of the data may be written.\n"
779"The number of bytes actually written is returned.");
780
781PyDoc_STRVAR(fileno_doc,
782"fileno() -> int. \"file descriptor\".\n"
783"\n"
784"This is needed for lower-level file interfaces, such the fcntl module.");
785
786PyDoc_STRVAR(seek_doc,
787"seek(offset: int[, whence: int]) -> None.  Move to new file position.\n"
788"\n"
789"Argument offset is a byte count.  Optional argument whence defaults to\n"
790"0 (offset from start of file, offset should be >= 0); other values are 1\n"
791"(move relative to current position, positive or negative), and 2 (move\n"
792"relative to end of file, usually negative, although many platforms allow\n"
793"seeking beyond the end of a file)."
794"\n"
795"Note that not all file objects are seekable.");
796
797#ifdef HAVE_FTRUNCATE
798PyDoc_STRVAR(truncate_doc,
799"truncate([size: int]) -> None.	 Truncate the file to at most size bytes.\n"
800"\n"
801"Size defaults to the current file position, as returned by tell()."
802"The current file position is changed to the value of size.");
803#endif
804
805PyDoc_STRVAR(tell_doc,
806"tell() -> int.	 Current file position");
807
808PyDoc_STRVAR(readinto_doc,
809"readinto() -> Undocumented.  Don't use this; it may go away.");
810
811PyDoc_STRVAR(close_doc,
812"close() -> None.  Close the file.\n"
813"\n"
814"A closed file cannot be used for further I/O operations.  close() may be\n"
815"called more than once without error.  Changes the fileno to -1.");
816
817PyDoc_STRVAR(isatty_doc,
818"isatty() -> bool.  True if the file is connected to a tty device.");
819
820PyDoc_STRVAR(seekable_doc,
821"seekable() -> bool.  True if file supports random-access.");
822
823PyDoc_STRVAR(readable_doc,
824"readable() -> bool.  True if file was opened in a read mode.");
825
826PyDoc_STRVAR(writable_doc,
827"writable() -> bool.  True if file was opened in a write mode.");
828
829static PyMethodDef fileio_methods[] = {
830	{"read",     (PyCFunction)fileio_read,	   METH_VARARGS, read_doc},
831	{"readall",  (PyCFunction)fileio_readall,  METH_NOARGS,  readall_doc},
832	{"readinto", (PyCFunction)fileio_readinto, METH_VARARGS, readinto_doc},
833	{"write",    (PyCFunction)fileio_write,	   METH_VARARGS, write_doc},
834	{"seek",     (PyCFunction)fileio_seek,	   METH_VARARGS, seek_doc},
835	{"tell",     (PyCFunction)fileio_tell,	   METH_VARARGS, tell_doc},
836#ifdef HAVE_FTRUNCATE
837	{"truncate", (PyCFunction)fileio_truncate, METH_VARARGS, truncate_doc},
838#endif
839	{"close",    (PyCFunction)fileio_close,	   METH_NOARGS,	 close_doc},
840	{"seekable", (PyCFunction)fileio_seekable, METH_NOARGS,	 seekable_doc},
841	{"readable", (PyCFunction)fileio_readable, METH_NOARGS,	 readable_doc},
842	{"writable", (PyCFunction)fileio_writable, METH_NOARGS,	 writable_doc},
843	{"fileno",   (PyCFunction)fileio_fileno,   METH_NOARGS,	 fileno_doc},
844	{"isatty",   (PyCFunction)fileio_isatty,   METH_NOARGS,	 isatty_doc},
845	{NULL,	     NULL}	       /* sentinel */
846};
847
848/* 'closed' and 'mode' are attributes for backwards compatibility reasons. */
849
850static PyObject *
851get_closed(PyFileIOObject *self, void *closure)
852{
853	return PyBool_FromLong((long)(self->fd < 0));
854}
855
856static PyObject *
857get_closefd(PyFileIOObject *self, void *closure)
858{
859	return PyBool_FromLong((long)(self->closefd));
860}
861
862static PyObject *
863get_mode(PyFileIOObject *self, void *closure)
864{
865	return PyString_FromString(mode_string(self));
866}
867
868static PyGetSetDef fileio_getsetlist[] = {
869	{"closed", (getter)get_closed, NULL, "True if the file is closed"},
870	{"closefd", (getter)get_closefd, NULL, 
871		"True if the file descriptor will be closed"},
872	{"mode", (getter)get_mode, NULL, "String giving the file mode"},
873	{0},
874};
875
876PyTypeObject PyFileIO_Type = {
877	PyVarObject_HEAD_INIT(NULL, 0)
878	"_FileIO",
879	sizeof(PyFileIOObject),
880	0,
881	(destructor)fileio_dealloc,		/* tp_dealloc */
882	0,					/* tp_print */
883	0,					/* tp_getattr */
884	0,					/* tp_setattr */
885	0,					/* tp_compare */
886	(reprfunc)fileio_repr,			/* tp_repr */
887	0,					/* tp_as_number */
888	0,					/* tp_as_sequence */
889	0,					/* tp_as_mapping */
890	0,					/* tp_hash */
891	0,					/* tp_call */
892	0,					/* tp_str */
893	PyObject_GenericGetAttr,		/* tp_getattro */
894	0,					/* tp_setattro */
895	0,					/* tp_as_buffer */
896	Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /* tp_flags */
897	fileio_doc,				/* tp_doc */
898	0,					/* tp_traverse */
899	0,					/* tp_clear */
900	0,					/* tp_richcompare */
901	offsetof(PyFileIOObject, weakreflist),	/* tp_weaklistoffset */
902	0,					/* tp_iter */
903	0,					/* tp_iternext */
904	fileio_methods,				/* tp_methods */
905	0,					/* tp_members */
906	fileio_getsetlist,			/* tp_getset */
907	0,					/* tp_base */
908	0,					/* tp_dict */
909	0,					/* tp_descr_get */
910	0,					/* tp_descr_set */
911	0,					/* tp_dictoffset */
912	fileio_init,				/* tp_init */
913	PyType_GenericAlloc,			/* tp_alloc */
914	fileio_new,				/* tp_new */
915	PyObject_Del,				/* tp_free */
916};
917
918static PyMethodDef module_methods[] = {
919	{NULL, NULL}
920};
921
922PyMODINIT_FUNC
923init_fileio(void)
924{
925	PyObject *m;	/* a module object */
926
927	m = Py_InitModule3("_fileio", module_methods,
928			   "Fast implementation of io.FileIO.");
929	if (m == NULL)
930		return;
931	if (PyType_Ready(&PyFileIO_Type) < 0)
932		return;
933	Py_INCREF(&PyFileIO_Type);
934	PyModule_AddObject(m, "_FileIO", (PyObject *) &PyFileIO_Type);
935}