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/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
#include <stdbool.h>
#include <stdint.h>
#include <sys/types.h>
#include "macro.h"
/* See source file for an API description. */
typedef struct Barrier Barrier;
enum {
BARRIER_SINGLE = 1LL,
BARRIER_ABORTION = INT64_MAX,
/* bias values to store state; keep @WE < @THEY < @I */
BARRIER_BIAS = INT64_MIN,
BARRIER_WE_ABORTED = BARRIER_BIAS + 1LL,
BARRIER_THEY_ABORTED = BARRIER_BIAS + 2LL,
BARRIER_I_ABORTED = BARRIER_BIAS + 3LL,
};
enum {
BARRIER_PARENT,
BARRIER_CHILD,
};
struct Barrier {
int me;
int them;
int pipe[2];
int64_t barriers;
};
#define BARRIER_NULL {-EBADF, -EBADF, {-EBADF, -EBADF}, 0}
int barrier_create(Barrier *obj);
Barrier* barrier_destroy(Barrier *b);
DEFINE_TRIVIAL_CLEANUP_FUNC(Barrier*, barrier_destroy);
void barrier_set_role(Barrier *b, unsigned role);
bool barrier_place(Barrier *b);
bool barrier_abort(Barrier *b);
bool barrier_wait_next(Barrier *b);
bool barrier_wait_abortion(Barrier *b);
bool barrier_sync_next(Barrier *b);
bool barrier_sync(Barrier *b);
static inline bool barrier_i_aborted(Barrier *b) {
return IN_SET(b->barriers, BARRIER_I_ABORTED, BARRIER_WE_ABORTED);
}
static inline bool barrier_they_aborted(Barrier *b) {
return IN_SET(b->barriers, BARRIER_THEY_ABORTED, BARRIER_WE_ABORTED);
}
static inline bool barrier_we_aborted(Barrier *b) {
return b->barriers == BARRIER_WE_ABORTED;
}
static inline bool barrier_is_aborted(Barrier *b) {
return IN_SET(b->barriers,
BARRIER_I_ABORTED, BARRIER_THEY_ABORTED, BARRIER_WE_ABORTED);
}
static inline bool barrier_place_and_sync(Barrier *b) {
(void) barrier_place(b);
return barrier_sync(b);
}
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