mirrors/cpython
1
0
Fork 0
mirror of https://github.com/python/cpython.git synced 2025-08-04 00:48:58 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 8

Issue #23668: Adds support for os.truncate and os.ftruncate on Windows

Browse source
This commit is contained in:
Steve Dower 2015-03-20 19:50:46 -07:00
parent c7d979f022
commit fe0a41aae4
5 changed files with 53 additions and 63 deletions
Download patch file Download diff file Expand all files Collapse all files

54
Modules/_io/fileio.c
View file

@ -839,9 +839,7 @@ static PyObject *
fileio_truncate(fileio *self, PyObject *args)
{
PyObject *posobj = NULL; /* the new size wanted by the user */
#ifndef MS_WINDOWS
Py_off_t pos;
#endif
int ret;
int fd;
@ -864,52 +862,6 @@ fileio_truncate(fileio *self, PyObject *args)
Py_INCREF(posobj);
}
#ifdef MS_WINDOWS
/* MS _chsize doesn't work if newsize doesn't fit in 32 bits,
so don't even try using it. */
{
PyObject *oldposobj, *tempposobj;
HANDLE hFile;
/* we save the file pointer position */
oldposobj = portable_lseek(fd, NULL, 1);
if (oldposobj == NULL) {
Py_DECREF(posobj);
return NULL;
}
/* we then move to the truncation position */
tempposobj = portable_lseek(fd, posobj, 0);
if (tempposobj == NULL) {
Py_DECREF(oldposobj);
Py_DECREF(posobj);
return NULL;
}
Py_DECREF(tempposobj);
/* Truncate. Note that this may grow the file! */
Py_BEGIN_ALLOW_THREADS
errno = 0;
hFile = (HANDLE)_get_osfhandle(fd);
ret = hFile == (HANDLE)-1; /* testing for INVALID_HANDLE value */
if (ret == 0) {
ret = SetEndOfFile(hFile) == 0;
if (ret)
errno = EACCES;
}
Py_END_ALLOW_THREADS
/* we restore the file pointer position in any case */
tempposobj = portable_lseek(fd, oldposobj, 0);
Py_DECREF(oldposobj);
if (tempposobj == NULL) {
Py_DECREF(posobj);
return NULL;
}
Py_DECREF(tempposobj);
}
#else
#if defined(HAVE_LARGEFILE_SUPPORT)
pos = PyLong_AsLongLong(posobj);
#else
@ -922,11 +874,13 @@ fileio_truncate(fileio *self, PyObject *args)
Py_BEGIN_ALLOW_THREADS
errno = 0;
#ifdef MS_WINDOWS
ret = _chsize_s(fd, pos);
#else
ret = ftruncate(fd, pos);
#endif
Py_END_ALLOW_THREADS
#endif /* !MS_WINDOWS */
if (ret != 0) {
Py_DECREF(posobj);
PyErr_SetFromErrno(PyExc_IOError);