Fix #11583. Changed os.path.isdir to use GetFileAttributes instead of os.stat.

By changing to the Windows GetFileAttributes API in nt._isdir we can figure
out if the path is a directory without opening the file via os.stat. This has
the minor benefit of speeding up os.path.isdir by at least 2x for regular
files and 10-15x improvements were seen on symbolic links (which opened the
file multiple times during os.stat). Since os.path.isdir is used in
several places on interpreter startup, we get a minor speedup in startup time.
This commit is contained in:
Brian Curtin 2011-06-08 18:43:57 -05:00
commit 9a82eaade3
3 changed files with 53 additions and 0 deletions

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@ -672,3 +672,16 @@ except ImportError:
def sameopenfile(f1, f2): def sameopenfile(f1, f2):
"""Test whether two file objects reference the same file""" """Test whether two file objects reference the same file"""
return _getfileinformation(f1) == _getfileinformation(f2) return _getfileinformation(f1) == _getfileinformation(f2)
try:
# The genericpath.isdir implementation uses os.stat and checks the mode
# attribute to tell whether or not the path is a directory.
# This is overkill on Windows - just pass the path to GetFileAttributes
# and check the attribute from there.
from nt import _isdir
except ImportError:
from genericpath import isdir as _isdir
def isdir(path):
return _isdir(path)

View File

@ -187,6 +187,9 @@ Core and Builtins
Library Library
------- -------
- Issue #11583: Speed up os.path.isdir on Windows by using GetFileAttributes
instead of os.stat.
- Issue #12021: Make mmap's read() method argument optional. Patch by Petri - Issue #12021: Make mmap's read() method argument optional. Patch by Petri
Lehtinen. Lehtinen.

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@ -2960,6 +2960,42 @@ posix__getfileinformation(PyObject *self, PyObject *args)
info.nFileIndexHigh, info.nFileIndexHigh,
info.nFileIndexLow); info.nFileIndexLow);
} }
static PyObject *
posix__isdir(PyObject *self, PyObject *args)
{
PyObject *opath;
char *path;
PyUnicodeObject *po;
DWORD attributes;
if (PyArg_ParseTuple(args, "U|:_isdir", &po)) {
Py_UNICODE *wpath = PyUnicode_AS_UNICODE(po);
attributes = GetFileAttributesW(wpath);
if (attributes == INVALID_FILE_ATTRIBUTES)
Py_RETURN_FALSE;
goto check;
}
/* Drop the argument parsing error as narrow strings
are also valid. */
PyErr_Clear();
if (!PyArg_ParseTuple(args, "O&:_isdir",
PyUnicode_FSConverter, &opath))
return NULL;
path = PyBytes_AsString(opath);
attributes = GetFileAttributesA(path);
if (attributes == INVALID_FILE_ATTRIBUTES)
Py_RETURN_FALSE;
check:
if (attributes & FILE_ATTRIBUTE_DIRECTORY)
Py_RETURN_TRUE;
else
Py_RETURN_FALSE;
}
#endif /* MS_WINDOWS */ #endif /* MS_WINDOWS */
PyDoc_STRVAR(posix_mkdir__doc__, PyDoc_STRVAR(posix_mkdir__doc__,
@ -9561,6 +9597,7 @@ static PyMethodDef posix_methods[] = {
{"_getfullpathname", posix__getfullpathname, METH_VARARGS, NULL}, {"_getfullpathname", posix__getfullpathname, METH_VARARGS, NULL},
{"_getfinalpathname", posix__getfinalpathname, METH_VARARGS, NULL}, {"_getfinalpathname", posix__getfinalpathname, METH_VARARGS, NULL},
{"_getfileinformation", posix__getfileinformation, METH_VARARGS, NULL}, {"_getfileinformation", posix__getfileinformation, METH_VARARGS, NULL},
{"_isdir", posix__isdir, METH_VARARGS, NULL},
#endif #endif
#ifdef HAVE_GETLOADAVG #ifdef HAVE_GETLOADAVG
{"getloadavg", posix_getloadavg, METH_NOARGS, posix_getloadavg__doc__}, {"getloadavg", posix_getloadavg, METH_NOARGS, posix_getloadavg__doc__},