new file mode 100644
--- /dev/null
+++ b/mercurial/osutil.c
@@ -0,0 +1,325 @@
+/*
+ osutil.c - native operating system services
+
+ Copyright 2007 Matt Mackall and others
+
+ This software may be used and distributed according to the terms of
+ the GNU General Public License, incorporated herein by reference.
+*/
+
+#define _ATFILE_SOURCE
+#define _LARGEFILE64_SOURCE
+#include <alloca.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "Python.h"
+
+struct listdir_stat {
+    PyObject_HEAD
+    struct stat st;
+};
+
+#define listdir_slot(name) \
+    static PyObject *listdir_stat_##name(PyObject *self, void *x) \
+    { \
+        return PyInt_FromLong(((struct listdir_stat *) self)->st.name); \
+    }
+
+listdir_slot(st_dev);
+listdir_slot(st_mode);
+listdir_slot(st_nlink);
+listdir_slot(st_size);
+listdir_slot(st_mtime);
+listdir_slot(st_ctime);
+
+static struct PyGetSetDef listdir_stat_getsets[] = {
+  {"st_dev", listdir_stat_st_dev, 0, 0, 0},
+  {"st_mode", listdir_stat_st_mode, 0, 0, 0},
+  {"st_nlink", listdir_stat_st_nlink, 0, 0, 0},
+  {"st_size", listdir_stat_st_size, 0, 0, 0},
+  {"st_mtime", listdir_stat_st_mtime, 0, 0, 0},
+  {"st_ctime", listdir_stat_st_ctime, 0, 0, 0},
+  {0, 0, 0, 0, 0}
+};
+
+static PyObject *listdir_stat_new(PyTypeObject *t, PyObject *a, PyObject *k)
+{
+    return (*t->tp_alloc)(t, 0);
+}
+
+static void listdir_stat_dealloc(PyObject *o)
+{
+    (*o->ob_type->tp_free)(o);
+}
+
+static PyTypeObject listdir_stat_type = {
+    PyObject_HEAD_INIT(NULL)
+    0,                         /*ob_size*/
+    "osutil.stat",             /*tp_name*/
+    sizeof(struct listdir_stat), /*tp_basicsize*/
+    0,                         /*tp_itemsize*/
+    (destructor)listdir_stat_dealloc, /*tp_dealloc*/
+    0,                         /*tp_print*/
+    0,                         /*tp_getattr*/
+    0,                         /*tp_setattr*/
+    0,                         /*tp_compare*/
+    0,                         /*tp_repr*/
+    0,                         /*tp_as_number*/
+    0,                         /*tp_as_sequence*/
+    0,                         /*tp_as_mapping*/
+    0,                         /*tp_hash */
+    0,                         /*tp_call*/
+    0,                         /*tp_str*/
+    0,                         /*tp_getattro*/
+    0,                         /*tp_setattro*/
+    0,                         /*tp_as_buffer*/
+    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+    "stat objects",           /* tp_doc */
+    0,                         /* tp_traverse */
+    0,                         /* tp_clear */
+    0,                         /* tp_richcompare */
+    0,                         /* tp_weaklistoffset */
+    0,                         /* tp_iter */
+    0,                         /* tp_iternext */
+    0,                         /* tp_methods */
+    0,                         /* tp_members */
+    listdir_stat_getsets,      /* tp_getset */
+    0,                         /* tp_base */
+    0,                         /* tp_dict */
+    0,                         /* tp_descr_get */
+    0,                         /* tp_descr_set */
+    0,                         /* tp_dictoffset */
+    0,                         /* tp_init */
+    0,                         /* tp_alloc */
+    listdir_stat_new,          /* tp_new */
+};
+
+static inline int mode_to_kind(int mode)
+{
+    if (S_ISREG(mode)) return S_IFREG;
+    if (S_ISDIR(mode)) return S_IFDIR;
+    if (S_ISLNK(mode)) return S_IFLNK;
+    if (S_ISBLK(mode)) return S_IFBLK;
+    if (S_ISCHR(mode)) return S_IFCHR;
+    if (S_ISFIFO(mode)) return S_IFIFO;
+    if (S_ISSOCK(mode)) return S_IFSOCK;
+    return mode;
+}
+
+static PyObject *listdir(PyObject *self, PyObject *args, PyObject *kwargs)
+{
+    DIR *dir = NULL;
+    struct dirent64 *ent;
+    PyObject *list = NULL;
+    PyObject *ctor_args = NULL;
+    int all_kinds = 1;
+    char *full_path;
+    int path_len;
+    int do_stat;
+    char *path;
+    int ret;
+    
+    {
+	static char *kwlist[] = { "path", "stat", NULL };    
+	PyObject *statobj = NULL;
+
+	if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s#|O:listdir", kwlist,
+					 &path, &path_len, &statobj))
+	    goto bail;
+
+	do_stat = statobj && PyObject_IsTrue(statobj);
+    }
+    
+    if ((dir = opendir(path)) == NULL) {
+	list = PyErr_SetFromErrnoWithFilename(PyExc_OSError, path);
+        goto bail;
+    }
+
+    if ((list = PyList_New(0)) == NULL)
+        goto bail;
+
+    full_path = alloca(path_len + PATH_MAX + 2);
+    memcpy(full_path, path, path_len);
+    full_path[path_len] = '/';
+
+    while ((ent = readdir64(dir))) {
+        PyObject *name = NULL;
+        PyObject *py_kind = NULL;
+        PyObject *val = NULL;
+        unsigned char d_type;
+        int kind = -1;
+
+        if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
+            continue;
+
+#ifdef DT_REG
+	if (do_stat)
+	    d_type = 0;
+	else
+	    d_type = ent->d_type;
+#else
+        d_type = 0;
+#endif
+
+        switch (d_type) {
+#ifdef DT_REG
+        case DT_REG: kind = S_IFREG; break;
+        case DT_DIR: kind = S_IFDIR; break;
+        case DT_LNK: kind = S_IFLNK; break;
+        case DT_BLK: kind = S_IFBLK; break;
+        case DT_CHR: kind = S_IFCHR; break;
+        case DT_FIFO: kind = S_IFIFO; break;
+        case DT_SOCK: kind = S_IFSOCK; break;
+#endif
+	default:
+	    if (all_kinds)
+		all_kinds = 0;
+	    break;
+	}
+
+        name = PyString_FromString(ent->d_name);
+	if (kind != -1)
+	    py_kind = PyInt_FromLong(kind);
+	else {
+	    py_kind = Py_None;
+	    Py_INCREF(Py_None);
+	}
+		
+        val = PyTuple_New(do_stat ? 3 : 2);
+	
+        if (name == NULL || py_kind == NULL || val == NULL) {
+            Py_XDECREF(name);
+            Py_XDECREF(py_kind);
+            Py_XDECREF(val);
+
+            goto bail;
+	}
+
+        PyTuple_SET_ITEM(val, 0, name);
+        PyTuple_SET_ITEM(val, 1, py_kind);
+	if (do_stat) {
+	    PyTuple_SET_ITEM(val, 2, Py_None);
+	    Py_INCREF(Py_None);
+	}
+
+        PyList_Append(list, val);
+        Py_DECREF(val);
+    }
+    
+    PyList_Sort(list);
+
+    if (do_stat || !all_kinds) {
+	ssize_t size = PyList_Size(list);
+	ssize_t i;
+#ifdef AT_SYMLINK_NOFOLLOW
+	int dfd = dirfd(dir);
+#endif
+
+	for (i = 0; i < size; i++) {
+	    PyObject *elt = PyList_GetItem(list, i);
+	    char *name = PyString_AsString(PyTuple_GET_ITEM(elt, 0));
+	    PyObject *py_st = NULL;
+	    PyObject *py_kind = PyTuple_GET_ITEM(elt, 1);
+	    int kind;
+
+	    kind = py_kind == Py_None ? -1 : PyInt_AsLong(py_kind);
+	    
+	    if (kind != -1 && !do_stat)
+		continue;
+
+            strcpy(full_path + path_len + 1, name);
+
+	    if (do_stat) {
+		struct listdir_stat *st;
+
+		if (ctor_args == NULL) {
+		    ctor_args = PyTuple_New(0);
+		    if (ctor_args == NULL)
+			goto bail;
+		}
+		
+		st = (struct listdir_stat *)
+		    PyObject_CallObject((PyObject *) &listdir_stat_type,
+					ctor_args);
+		if (st == NULL)
+		    goto bail;
+#ifdef AT_SYMLINK_NOFOLLOW
+		ret = fstatat(dfd, name, &st->st, AT_SYMLINK_NOFOLLOW);
+#else
+		ret = lstat(full_path, &st->st);
+#endif
+		if (ret == -1) {
+		    list = PyErr_SetFromErrnoWithFilename(PyExc_OSError,
+							  full_path);
+		    goto bail;
+		}
+		if (kind == -1)
+		    kind = mode_to_kind(st->st.st_mode);
+		py_st = (PyObject *) st;
+	    } else {
+		struct stat buf;
+#ifdef AT_SYMLINK_NOFOLLOW
+		ret = fstatat(dfd, ent->d_name, &buf, AT_SYMLINK_NOFOLLOW);
+#else
+		ret = lstat(full_path, &buf);
+#endif
+		if (ret == -1) {
+		    list = PyErr_SetFromErrnoWithFilename(PyExc_OSError,
+							  full_path);
+		    goto bail;
+		}
+		if (kind == -1)
+		    kind = mode_to_kind(buf.st_mode);
+	    }
+
+	    if (py_kind == Py_None && kind != -1) {
+		py_kind = PyInt_FromLong(kind);
+		if (py_kind == NULL)
+		    goto bail;
+		Py_XDECREF(Py_None);
+		PyTuple_SET_ITEM(elt, 1, py_kind);
+	    }
+
+	    if (do_stat) {
+		if (py_st == NULL) {
+		    py_st = Py_None;
+		    Py_INCREF(Py_None);
+		}
+		PyTuple_SET_ITEM(elt, 2, py_st);
+	    }
+        }
+    }
+
+    goto done;
+
+bail:
+    Py_XDECREF(list);
+
+done:
+    Py_XDECREF(ctor_args);
+    if (dir)
+        closedir(dir);
+
+    return list;
+}
+
+static char osutil_doc[] = "Native operating system services.";
+
+static PyMethodDef methods[] = {
+    {"listdir", (PyCFunction) listdir, METH_VARARGS | METH_KEYWORDS,
+     "list a directory\n"},
+    {NULL, NULL}
+};
+
+PyMODINIT_FUNC initosutil(void)
+{
+    if (PyType_Ready(&listdir_stat_type) == -1)
+        return;
+
+    Py_InitModule3("osutil", methods, osutil_doc);
+}