From f3b2d88b676d5624aed157a70bfa5b606f8249ed Mon Sep 17 00:00:00 2001 From: Antoine Pitrou Date: Mon, 30 Jan 2012 22:08:52 +0100 Subject: Issue #8828: Add new function os.replace(), for cross-platform renaming with overwriting. --- Doc/library/os.rst | 18 ++++++++++++++++-- Lib/test/test_os.py | 12 ++++++++++++ Misc/NEWS | 3 +++ Modules/posixmodule.c | 47 ++++++++++++++++++++++++++++++++++------------- 4 files changed, 65 insertions(+), 15 deletions(-) diff --git a/Doc/library/os.rst b/Doc/library/os.rst index 3c302a4..617f276 100644 --- a/Doc/library/os.rst +++ b/Doc/library/os.rst @@ -1889,8 +1889,9 @@ Files and Directories Unix flavors if *src* and *dst* are on different filesystems. If successful, the renaming will be an atomic operation (this is a POSIX requirement). On Windows, if *dst* already exists, :exc:`OSError` will be raised even if it is a - file; there may be no way to implement an atomic rename when *dst* names an - existing file. + file. + + If you want cross-platform overwriting of the destination, use :func:`replace`. Availability: Unix, Windows. @@ -1908,6 +1909,19 @@ Files and Directories permissions needed to remove the leaf directory or file. +.. function:: replace(src, dst) + + Rename the file or directory *src* to *dst*. If *dst* is a directory, + :exc:`OSError` will be raised. If *dst* exists and is a file, it will + be replaced silently if the user has permission. The operation may fail + if *src* and *dst* are on different filesystems. If successful, + the renaming will be an atomic operation (this is a POSIX requirement). + + Availability: Unix, Windows + + .. versionadded:: 3.3 + + .. function:: rmdir(path) Remove (delete) the directory *path*. Only works when the directory is diff --git a/Lib/test/test_os.py b/Lib/test/test_os.py index e78db48..293005b 100644 --- a/Lib/test/test_os.py +++ b/Lib/test/test_os.py @@ -129,6 +129,18 @@ class FileTests(unittest.TestCase): self.fdopen_helper('r') self.fdopen_helper('r', 100) + def test_replace(self): + TESTFN2 = support.TESTFN + ".2" + with open(support.TESTFN, 'w') as f: + f.write("1") + with open(TESTFN2, 'w') as f: + f.write("2") + self.addCleanup(os.unlink, TESTFN2) + os.replace(support.TESTFN, TESTFN2) + self.assertRaises(FileNotFoundError, os.stat, support.TESTFN) + with open(TESTFN2, 'r') as f: + self.assertEqual(f.read(), "1") + # Test attributes on return values from os.*stat* family. class StatAttributeTests(unittest.TestCase): diff --git a/Misc/NEWS b/Misc/NEWS index 2607618..8b67257 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -463,6 +463,9 @@ Core and Builtins Library ------- +- Issue #8828: Add new function os.replace(), for cross-platform renaming + with overwriting. + - Issue #13848: open() and the FileIO constructor now check for NUL characters in the file name. Patch by Hynek Schlawack. diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c index 1797a2f..2269fe9 100644 --- a/Modules/posixmodule.c +++ b/Modules/posixmodule.c @@ -3280,17 +3280,16 @@ posix_setpriority(PyObject *self, PyObject *args) #endif /* HAVE_SETPRIORITY */ -PyDoc_STRVAR(posix_rename__doc__, -"rename(old, new)\n\n\ -Rename a file or directory."); - static PyObject * -posix_rename(PyObject *self, PyObject *args) +internal_rename(PyObject *self, PyObject *args, int is_replace) { #ifdef MS_WINDOWS PyObject *src, *dst; BOOL result; - if (PyArg_ParseTuple(args, "UU:rename", &src, &dst)) + int flags = is_replace ? MOVEFILE_REPLACE_EXISTING : 0; + if (PyArg_ParseTuple(args, + is_replace ? "UU:replace" : "UU:rename", + &src, &dst)) { wchar_t *wsrc, *wdst; @@ -3301,16 +3300,17 @@ posix_rename(PyObject *self, PyObject *args) if (wdst == NULL) return NULL; Py_BEGIN_ALLOW_THREADS - result = MoveFileW(wsrc, wdst); + result = MoveFileExW(wsrc, wdst, flags); Py_END_ALLOW_THREADS if (!result) - return win32_error("rename", NULL); + return win32_error(is_replace ? "replace" : "rename", NULL); Py_INCREF(Py_None); return Py_None; } else { PyErr_Clear(); - if (!PyArg_ParseTuple(args, "O&O&:rename", + if (!PyArg_ParseTuple(args, + is_replace ? "O&O&:replace" : "O&O&:rename", PyUnicode_FSConverter, &src, PyUnicode_FSConverter, &dst)) return NULL; @@ -3319,15 +3319,15 @@ posix_rename(PyObject *self, PyObject *args) goto error; Py_BEGIN_ALLOW_THREADS - result = MoveFileA(PyBytes_AS_STRING(src), - PyBytes_AS_STRING(dst)); + result = MoveFileExA(PyBytes_AS_STRING(src), + PyBytes_AS_STRING(dst), flags); Py_END_ALLOW_THREADS Py_XDECREF(src); Py_XDECREF(dst); if (!result) - return win32_error("rename", NULL); + return win32_error(is_replace ? "replace" : "rename", NULL); Py_INCREF(Py_None); return Py_None; @@ -3337,10 +3337,30 @@ error: return NULL; } #else - return posix_2str(args, "O&O&:rename", rename); + return posix_2str(args, + is_replace ? "O&O&:replace" : "O&O&:rename", rename); #endif } +PyDoc_STRVAR(posix_rename__doc__, +"rename(old, new)\n\n\ +Rename a file or directory."); + +static PyObject * +posix_rename(PyObject *self, PyObject *args) +{ + return internal_rename(self, args, 0); +} + +PyDoc_STRVAR(posix_replace__doc__, +"replace(old, new)\n\n\ +Rename a file or directory, overwriting the destination."); + +static PyObject * +posix_replace(PyObject *self, PyObject *args) +{ + return internal_rename(self, args, 1); +} PyDoc_STRVAR(posix_rmdir__doc__, "rmdir(path)\n\n\ @@ -10555,6 +10575,7 @@ static PyMethodDef posix_methods[] = { {"readlink", win_readlink, METH_VARARGS, win_readlink__doc__}, #endif /* !defined(HAVE_READLINK) && defined(MS_WINDOWS) */ {"rename", posix_rename, METH_VARARGS, posix_rename__doc__}, + {"replace", posix_replace, METH_VARARGS, posix_replace__doc__}, {"rmdir", posix_rmdir, METH_VARARGS, posix_rmdir__doc__}, {"stat", posix_stat, METH_VARARGS, posix_stat__doc__}, {"stat_float_times", stat_float_times, METH_VARARGS, stat_float_times__doc__}, -- cgit v0.12