mercurial/cext/util.h

interfaces: introduce and use a protocol class for the `mpatch` module

See f2832de2a46c for details when this was done for the `bdiff` module.

Two things worth pointing out-

  1) The `cffi` module "inherits" the `pure` implementation of `patchedsize()`
     because of its wildcard import.
  2) It's odd that the `mpatchError` lives in both `pure` and `cext` modules.

I initially thought to move the exception into the new class, and make the
existing class name an alias to the class in the new location, but the exception
is created in C code by the `cext` module, so that won't work.  I don't think a
protocol class is approriate, because there's nothing special about the class to
distinguish from any other `Exception`.  Fortunately, nobody is catching this
exception in core, so we can kick the can down the road.

/*
 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"

/* clang-format off */
typedef struct {
	PyObject_HEAD
	int flags;
	int mode;
	int size;
	int mtime_s;
	int mtime_ns;
} dirstateItemObject;
/* clang-format on */

static const int dirstate_flag_wc_tracked = 1 << 0;
static const int dirstate_flag_p1_tracked = 1 << 1;
static const int dirstate_flag_p2_info = 1 << 2;
static const int dirstate_flag_mode_exec_perm = 1 << 3;
static const int dirstate_flag_mode_is_symlink = 1 << 4;
static const int dirstate_flag_has_fallback_exec = 1 << 5;
static const int dirstate_flag_fallback_exec = 1 << 6;
static const int dirstate_flag_has_fallback_symlink = 1 << 7;
static const int dirstate_flag_fallback_symlink = 1 << 8;
static const int dirstate_flag_expected_state_is_modified = 1 << 9;
static const int dirstate_flag_has_meaningful_data = 1 << 10;
static const int dirstate_flag_has_mtime = 1 << 11;
static const int dirstate_flag_mtime_second_ambiguous = 1 << 12;
static const int dirstate_flag_directory = 1 << 13;
static const int dirstate_flag_all_unknown_recorded = 1 << 14;
static const int dirstate_flag_all_ignored_recorded = 1 << 15;

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

#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);
}

/* Convert a PyInt or PyLong to a long. Returns false if there is an
   error, in which case an exception will already have been set. */
static inline bool pylong_to_long(PyObject *pylong, long *out)
{
	*out = PyLong_AsLong(pylong);
	/* Fast path to avoid hitting PyErr_Occurred if the value was obviously
	 * not an error. */
	if (*out != -1) {
		return true;
	}
	return PyErr_Occurred() == NULL;
}

#endif /* _HG_UTIL_H_ */