view mercurial/cext/util.h @ 40327:55836a34f41b

exchangev2: recognize narrow patterns when pulling

pulloperation instances were recently taught to record file
include and exclude patterns to facilitate narrow file transfer.
Teaching the exchangev2 code to transfer a subset of files is
as simple as constructing a narrow matcher from these patterns and
filtering all seen file paths through it.

Keep in mind that this change only influences file data: we're
still fetching all changeset and manifest data. So, there's still
a ton of "partial clone" to implement in exchangev2.

On a personal note, I derive gratification that this feature requires
very few lines of new code to implement.

To test this, we implemented a minimal extension which allows us to specify
--include/--exclude to clone. While the narrow extension provides these
arguments, I explicitly wanted to test this functionality without the
narrow extension enabled, as that extension monkeypatches various things
and I want to isolate the behavior of core Mercurial.

Differential Revision: https://phab.mercurial-scm.org/D5132

/*
 util.h - utility functions for interfacing with the various python APIs.

 This software may be used and distributed according to the terms of
 the GNU General Public License, incorporated herein by reference.
*/

#ifndef _HG_UTIL_H_
#define _HG_UTIL_H_

#include "compat.h"

#if PY_MAJOR_VERSION >= 3
#define IS_PY3K
#endif

/* helper to switch things like string literal depending on Python version */
#ifdef IS_PY3K
#define PY23(py2, py3) py3
#else
#define PY23(py2, py3) py2
#endif

/* clang-format off */
typedef struct {
	PyObject_HEAD
	char state;
	int mode;
	int size;
	int mtime;
} dirstateTupleObject;
/* clang-format on */

extern PyTypeObject dirstateTupleType;
#define dirstate_tuple_check(op) (Py_TYPE(op) == &dirstateTupleType)

#ifndef MIN
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#endif
/* VC9 doesn't include bool and lacks stdbool.h based on my searching */
#if defined(_MSC_VER) || __STDC_VERSION__ < 199901L
#define true 1
#define false 0
typedef unsigned char bool;
#else
#include <stdbool.h>
#endif

static inline PyObject *_dict_new_presized(Py_ssize_t expected_size)
{
	/* _PyDict_NewPresized expects a minused parameter, but it actually
	   creates a dictionary that's the nearest power of two bigger than the
	   parameter. For example, with the initial minused = 1000, the
	   dictionary created has size 1024. Of course in a lot of cases that
	   can be greater than the maximum load factor Python's dict object
	   expects (= 2/3), so as soon as we cross the threshold we'll resize
	   anyway. So create a dictionary that's at least 3/2 the size. */
	return _PyDict_NewPresized(((1 + expected_size) / 2) * 3);
}

#endif /* _HG_UTIL_H_ */