/*

 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

#include <Python.h>

#ifdef _WIN32

#include <windows.h>

#else

#include <dirent.h>

#include <fcntl.h>

#include <string.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <unistd.h>

#endif

#ifdef _WIN32

/*

stat struct compatible with hg expectations

Mercurial only uses st_mode, st_size and st_mtime

the rest is kept to minimize changes between implementations

*/

struct hg_stat {

	int st_dev;

	int st_mode;

	int st_nlink;

	__int64 st_size;

	int st_mtime;

	int st_ctime;

};

struct listdir_stat {

	PyObject_HEAD

	struct hg_stat st;

};

#else

struct listdir_stat {

	PyObject_HEAD

	struct stat st;

};

#endif

#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)

#ifdef _WIN32

static PyObject *listdir_stat_st_size(PyObject *self, void *x)

{

	return PyLong_FromLongLong(

		(PY_LONG_LONG)((struct listdir_stat *)self)->st.st_size);

}

#else

listdir_slot(st_size)

#endif

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 */

};

#ifdef _WIN32

static int to_python_time(const FILETIME *tm)

{

	/* number of seconds between epoch and January 1 1601 */

	const __int64 a0 = (__int64)134774L * (__int64)24L * (__int64)3600L;

	/* conversion factor from 100ns to 1s */

	const __int64 a1 = 10000000;

	/* explicit (int) cast to suspend compiler warnings */

	return (int)((((__int64)tm->dwHighDateTime << 32)

			+ tm->dwLowDateTime) / a1 - a0);

}

static PyObject *make_item(const WIN32_FIND_DATAA *fd, int wantstat)

{

	PyObject *py_st;

	struct hg_stat *stp;

	int kind = (fd->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)

		? _S_IFDIR : _S_IFREG;

	if (!wantstat)

		return Py_BuildValue("si", fd->cFileName, kind);

	py_st = PyObject_CallObject((PyObject *)&listdir_stat_type, NULL);

	if (!py_st)

		return NULL;

	stp = &((struct listdir_stat *)py_st)->st;

	/*

	use kind as st_mode

	rwx bits on Win32 are meaningless

	and Hg does not use them anyway

	*/

	stp->st_mode  = kind;

	stp->st_mtime = to_python_time(&fd->ftLastWriteTime);

	stp->st_ctime = to_python_time(&fd->ftCreationTime);

	if (kind == _S_IFREG)

		stp->st_size =	((__int64)fd->nFileSizeHigh << 32)

				+ fd->nFileSizeLow;

	return Py_BuildValue("siN", fd->cFileName,

		kind, py_st);

}

static PyObject *_listdir(char *path, int plen, int wantstat, char *skip)

{

	PyObject *rval = NULL; /* initialize - return value */

	PyObject *list;

	HANDLE fh;

	WIN32_FIND_DATAA fd;

	char *pattern;

	/* build the path + \* pattern string */

	pattern = malloc(plen+3); /* path + \* + \0 */

	if (!pattern) {

		PyErr_NoMemory();

		goto error_nomem;

	}

	strcpy(pattern, path);

	if (plen > 0) {

		char c = path[plen-1];

		if (c != ':' && c != '/' && c != '\\')

			pattern[plen++] = '\\';

	}

	strcpy(pattern + plen, "*");

	fh = FindFirstFileA(pattern, &fd);

	if (fh == INVALID_HANDLE_VALUE) {

		PyErr_SetFromWindowsErrWithFilename(GetLastError(), path);

		goto error_file;

	}

	list = PyList_New(0);

	if (!list)

		goto error_list;

	do {

		PyObject *item;

		if (fd.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {

			if (!strcmp(fd.cFileName, ".")

			|| !strcmp(fd.cFileName, ".."))

				continue;

			if (skip && !strcmp(fd.cFileName, skip)) {

				rval = PyList_New(0);

				goto error;

			}

		}

		item = make_item(&fd, wantstat);

		if (!item)

			goto error;

		if (PyList_Append(list, item)) {

			Py_XDECREF(item);

			goto error;

		}

		Py_XDECREF(item);

	} while (FindNextFileA(fh, &fd));

	if (GetLastError() != ERROR_NO_MORE_FILES) {

		PyErr_SetFromWindowsErrWithFilename(GetLastError(), path);

		goto error;

	}

	rval = list;

	Py_XINCREF(rval);

error:

	Py_XDECREF(list);

error_list:

	FindClose(fh);

error_file:

	free(pattern);

error_nomem:

	return rval;

}

#else

int entkind(struct dirent *ent)

{

#ifdef DT_REG

	switch (ent->d_type) {

	case DT_REG: return S_IFREG;

	case DT_DIR: return S_IFDIR;

	case DT_LNK: return S_IFLNK;

	case DT_BLK: return S_IFBLK;

	case DT_CHR: return S_IFCHR;

	case DT_FIFO: return S_IFIFO;

	case DT_SOCK: return S_IFSOCK;

	}

#endif

	return -1;

}

static PyObject *_listdir(char *path, int pathlen, int keepstat, char *skip)

{

	PyObject *list, *elem, *stat, *ret = NULL;

	char fullpath[PATH_MAX + 10];

	int kind, err;

	struct stat st;

	struct dirent *ent;

	DIR *dir;

#ifdef AT_SYMLINK_NOFOLLOW

	int dfd = -1;

#endif

	if (pathlen >= PATH_MAX) {

		PyErr_SetString(PyExc_ValueError, "path too long");

		goto error_value;

	}

	strncpy(fullpath, path, PATH_MAX);

	fullpath[pathlen] = '/';

#ifdef AT_SYMLINK_NOFOLLOW

	dfd = open(path, O_RDONLY);

	if (dfd == -1) {

		PyErr_SetFromErrnoWithFilename(PyExc_OSError, path);

		goto error_value;

	}

	dir = fdopendir(dfd);

#else

	dir = opendir(path);

#endif

	if (!dir) {

		PyErr_SetFromErrnoWithFilename(PyExc_OSError, path);

		goto error_dir;

 	}

	list = PyList_New(0);

	if (!list)

		goto error_list;

	while ((ent = readdir(dir))) {

		if (!strcmp(ent->d_name, ".") || !strcmp(ent->d_name, ".."))

			continue;

		kind = entkind(ent);

		if (kind == -1 || keepstat) {

#ifdef AT_SYMLINK_NOFOLLOW

			err = fstatat(dfd, ent->d_name, &st,

				      AT_SYMLINK_NOFOLLOW);

#else

			strncpy(fullpath + pathlen + 1, ent->d_name,

				PATH_MAX - pathlen);

			fullpath[PATH_MAX] = 0;

			err = lstat(fullpath, &st);

#endif

			if (err == -1) {

				strncpy(fullpath + pathlen + 1, ent->d_name,

					PATH_MAX - pathlen);

				fullpath[PATH_MAX] = 0;

				PyErr_SetFromErrnoWithFilename(PyExc_OSError,

							       fullpath);

				goto error;

			}

			kind = st.st_mode & S_IFMT;

		}

		/* quit early? */

		if (skip && kind == S_IFDIR && !strcmp(ent->d_name, skip)) {

			ret = PyList_New(0);

			goto error;

		}

		if (keepstat) {

			stat = PyObject_CallObject((PyObject *)&listdir_stat_type, NULL);

			if (!stat)

				goto error;

			memcpy(&((struct listdir_stat *)stat)->st, &st, sizeof(st));

			elem = Py_BuildValue("siN", ent->d_name, kind, stat);

		} else

			elem = Py_BuildValue("si", ent->d_name, kind);

		if (!elem)

			goto error;

		PyList_Append(list, elem);

		Py_DECREF(elem);

	}

	ret = list;

	Py_INCREF(ret);

error:

	Py_DECREF(list);

error_list:

	closedir(dir);

error_dir:

#ifdef AT_SYMLINK_NOFOLLOW

	close(dfd);

#endif

error_value:

	return ret;

}

#endif /* ndef _WIN32 */

static PyObject *listdir(PyObject *self, PyObject *args, PyObject *kwargs)

{

	PyObject *statobj = NULL; /* initialize - optional arg */

	PyObject *skipobj = NULL; /* initialize - optional arg */

	char *path, *skip = NULL;

	int wantstat, plen;

	static char *kwlist[] = {"path", "stat", "skip", NULL};

	if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s#|OO:listdir",

			kwlist, &path, &plen, &statobj, &skipobj))

		return NULL;

	wantstat = statobj && PyObject_IsTrue(statobj);

	if (skipobj && skipobj != Py_None) {

		skip = PyString_AsString(skipobj);

		if (!skip)

			return NULL;

	}

	return _listdir(path, plen, wantstat, skip);

}

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);

}