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authorLuke Shumaker <lukeshu@sbcglobal.net>2016-07-27 23:53:49 -0400
committerLuke Shumaker <lukeshu@sbcglobal.net>2016-07-27 23:53:49 -0400
commit8afdea4cef99e4e22d7e941cb779cefcb65d2284 (patch)
treee674a72577d988bb8ecbc14338913dd0e17cee09 /src/libbasic/include/basic/barrier.h
parent46565171d49814f56b340d8cd28d7a855cad8dee (diff)
./move.sh
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diff --git a/src/libbasic/include/basic/barrier.h b/src/libbasic/include/basic/barrier.h
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+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 David Herrmann <dh.herrmann@gmail.com>
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#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 {-1, -1, {-1, -1}, 0}
+
+int barrier_create(Barrier *obj);
+void barrier_destroy(Barrier *b);
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(Barrier*, barrier_destroy);
+
+void barrier_set_role(Barrier *b, unsigned int 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 b->barriers == BARRIER_I_ABORTED || b->barriers == BARRIER_WE_ABORTED;
+}
+
+static inline bool barrier_they_aborted(Barrier *b) {
+ return b->barriers == BARRIER_THEY_ABORTED || b->barriers == 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 b->barriers == BARRIER_I_ABORTED || b->barriers == BARRIER_THEY_ABORTED || b->barriers == BARRIER_WE_ABORTED;
+}
+
+static inline bool barrier_place_and_sync(Barrier *b) {
+ (void) barrier_place(b);
+ return barrier_sync(b);
+}