diff options
Diffstat (limited to 'libpthread/linuxthreads/queue.h')
-rw-r--r-- | libpthread/linuxthreads/queue.h | 61 |
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; +} |