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-rw-r--r--libpthread/linuxthreads/queue.h61
1 files changed, 61 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/queue.h b/libpthread/linuxthreads/queue.h
new file mode 100644
index 000000000..28bd75531
--- /dev/null
+++ b/libpthread/linuxthreads/queue.h
@@ -0,0 +1,61 @@
+/* Linuxthreads - a simple clone()-based implementation of Posix */
+/* threads for Linux. */
+/* Copyright (C) 1996 Xavier Leroy (Xavier.Leroy@inria.fr) */
+/* */
+/* This program is free software; you can redistribute it and/or */
+/* modify it under the terms of the GNU Library General Public License */
+/* as published by the Free Software Foundation; either version 2 */
+/* of the License, or (at your option) any later version. */
+/* */
+/* This program 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 Library General Public License for more details. */
+
+/* Waiting queues */
+
+/* Waiting queues are represented by lists of thread descriptors
+ linked through their p_nextwaiting field. The lists are kept
+ sorted by decreasing priority, and then decreasing waiting time. */
+
+static inline void enqueue(pthread_descr * q, pthread_descr th)
+{
+ int prio = th->p_priority;
+ ASSERT(th->p_nextwaiting == NULL);
+ for (; *q != NULL; q = &((*q)->p_nextwaiting)) {
+ if (prio > (*q)->p_priority) {
+ th->p_nextwaiting = *q;
+ *q = th;
+ return;
+ }
+ }
+ *q = th;
+}
+
+static inline pthread_descr dequeue(pthread_descr * q)
+{
+ pthread_descr th;
+ th = *q;
+ if (th != NULL) {
+ *q = th->p_nextwaiting;
+ th->p_nextwaiting = NULL;
+ }
+ return th;
+}
+
+static inline int remove_from_queue(pthread_descr * q, pthread_descr th)
+{
+ for (; *q != NULL; q = &((*q)->p_nextwaiting)) {
+ if (*q == th) {
+ *q = th->p_nextwaiting;
+ th->p_nextwaiting = NULL;
+ return 1;
+ }
+ }
+ return 0;
+}
+
+static inline int queue_is_empty(pthread_descr * q)
+{
+ return *q == NULL;
+}