shared: add simple priority queue implementation

1 files changed, 39 insertions, 0 deletions

diff --git a/src/shared/prioq.h b/src/shared/prioq.h
new file mode 100644
index 0000000000..1b5b05e7c7
--- /dev/null
+++ b/src/shared/prioq.h
@@ -0,0 +1,39 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Lennart Poettering
+
+  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 "hashmap.h"
+
+typedef struct Prioq Prioq;
+
+Prioq *prioq_new(compare_func_t compare);
+void prioq_free(Prioq *q);
+
+int prioq_put(Prioq *q, void *data, unsigned *idx);
+int prioq_remove(Prioq *q, void *data, unsigned *idx);
+int prioq_reshuffle(Prioq *q, void *data, unsigned *idx);
+
+void *prioq_peek(Prioq *q);
+void *prioq_pop(Prioq *q);
+
+unsigned prioq_size(Prioq *q);
+bool prioq_isempty(Prioq *q);