view mercurial/osutil.c @ 6858:8f256bf98219

Add support for multiple possible bisect results (issue1228, issue1182)

The real reason for both issue is that bisect can not handle cases where there
are multiple possibilities for the result.

Example (from issue1228):
rev 0 -> good
rev 1 -> skipped
rev 2 -> skipped
rev 3 -> skipped
rev 4 -> bad

Note that this patch does not only fix the reported Assertion Error but also
the problem of a non converging bisect:

hg init
for i in `seq 3`; do echo $i > $i; hg add $i; hg ci -m$i; done
hg bisect -b 2
hg bisect -g 0
hg bisect -s

From this state on, you can:
 a) mark as bad forever (non converging!)
 b) mark as good to get an inconsistent state
 c) skip for the Assertion Error

Minor description and code edits by pmezard.

/*
 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>
#include <dirent.h>
#include <fcntl.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.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 PyObject *listfiles(PyObject *list, DIR *dir,
			   int keep_stat, int *need_stat)
{
	struct dirent *ent;
	PyObject *name, *py_kind, *val;

#ifdef DT_REG
	*need_stat = 0;
#else
	*need_stat = 1;
#endif

	for (ent = readdir(dir); ent; ent = readdir(dir)) {
		int kind = -1;

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

#ifdef DT_REG
		if (!keep_stat)
			switch (ent->d_type) {
			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;
			default:
				*need_stat = 0;
				break;
			}
#endif

		if (kind != -1)
			py_kind = PyInt_FromLong(kind);
		else {
			py_kind = Py_None;
			Py_INCREF(Py_None);
		}

		val = PyTuple_New(keep_stat ? 3 : 2);
		name = PyString_FromString(ent->d_name);

		if (!name || !py_kind || !val) {
			Py_XDECREF(name);
			Py_XDECREF(py_kind);
			Py_XDECREF(val);
			return PyErr_NoMemory();
		}

		PyTuple_SET_ITEM(val, 0, name);
		PyTuple_SET_ITEM(val, 1, py_kind);
		if (keep_stat) {
			PyTuple_SET_ITEM(val, 2, Py_None);
			Py_INCREF(Py_None);
		}

		PyList_Append(list, val);
		Py_DECREF(val);
	}

	return 0;
}

static PyObject *statfiles(PyObject *list, PyObject *ctor_args, int keep,
			   char *path, int len, int dfd)
{
	struct stat buf;
	struct stat *stp = &buf;
	int kind;
	int ret;
	ssize_t i;
	ssize_t size = PyList_Size(list);

	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);

		kind = py_kind == Py_None ? -1 : PyInt_AsLong(py_kind);
		if (kind != -1 && !keep)
			continue;

		strncpy(path + len + 1, name, PATH_MAX - len);
		path[PATH_MAX] = 0;

		if (keep) {
			py_st = PyObject_CallObject(
				(PyObject *)&listdir_stat_type, ctor_args);
			if (!py_st)
				return PyErr_NoMemory();
			stp = &((struct listdir_stat *)py_st)->st;
			PyTuple_SET_ITEM(elt, 2, py_st);
		}

#ifdef AT_SYMLINK_NOFOLLOW
		ret = fstatat(dfd, name, stp, AT_SYMLINK_NOFOLLOW);
#else
		ret = lstat(path, stp);
#endif
		if (ret == -1)
			return PyErr_SetFromErrnoWithFilename(PyExc_OSError,
							      path);

		if (kind == -1) {
			if (S_ISREG(stp->st_mode))
				kind = S_IFREG;
			else if (S_ISDIR(stp->st_mode))
				kind = S_IFDIR;
			else if (S_ISLNK(stp->st_mode))
				kind = S_IFLNK;
			else if (S_ISBLK(stp->st_mode))
				kind = S_IFBLK;
			else if (S_ISCHR(stp->st_mode))
				kind = S_IFCHR;
			else if (S_ISFIFO(stp->st_mode))
				kind = S_IFIFO;
			else if (S_ISSOCK(stp->st_mode))
				kind = S_IFSOCK;
			else
				kind = stp->st_mode;
		}

		if (py_kind == Py_None && kind != -1) {
			py_kind = PyInt_FromLong(kind);
			if (!py_kind)
				return PyErr_NoMemory();
			Py_XDECREF(Py_None);
			PyTuple_SET_ITEM(elt, 1, py_kind);
		}
	}

	return 0;
}

static PyObject *listdir(PyObject *self, PyObject *args, PyObject *kwargs)
{
	static char *kwlist[] = { "path", "stat", NULL };
	DIR *dir = NULL;
	PyObject *statobj = NULL;
	PyObject *list = NULL;
	PyObject *err = NULL;
	PyObject *ctor_args = NULL;
	char *path;
	char full_path[PATH_MAX + 10];
	int path_len;
	int need_stat, keep_stat;
	int dfd;

	if (!PyArg_ParseTupleAndKeywords(args, kwargs, "s#|O:listdir", kwlist,
					 &path, &path_len, &statobj))
		goto bail;

	keep_stat = statobj && PyObject_IsTrue(statobj);

#ifdef AT_SYMLINK_NOFOLLOW
	dfd = open(path, O_RDONLY);
	dir = fdopendir(dfd);
#else
	dir = opendir(path);
	dfd = -1;
#endif
	if (!dir) {
		err = PyErr_SetFromErrnoWithFilename(PyExc_OSError, path);
		goto bail;
	}

	list = PyList_New(0);
	ctor_args = PyTuple_New(0);
	if (!list || !ctor_args)
		goto bail;

	strncpy(full_path, path, PATH_MAX);
	full_path[path_len] = '/';

	err = listfiles(list, dir, keep_stat, &need_stat);
	if (err)
		goto bail;

	PyList_Sort(list);

	if (!keep_stat && !need_stat)
		goto done;

	err = statfiles(list, ctor_args, keep_stat, full_path, path_len, dfd);
	if (!err)
		goto done;

 bail:
	Py_XDECREF(list);

 done:
	Py_XDECREF(ctor_args);
	if (dir)
		closedir(dir);
	return err ? err : 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);
}