From 0b44a0315b47dd8eced9f3b7f31580cf14bbfc01 Mon Sep 17 00:00:00 2001 From: Rich Felker Date: Sat, 12 Feb 2011 00:22:29 -0500 Subject: initial check-in, version 0.5.0 --- src/thread/pthread_mutex_trylock.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 src/thread/pthread_mutex_trylock.c (limited to 'src/thread/pthread_mutex_trylock.c') diff --git a/src/thread/pthread_mutex_trylock.c b/src/thread/pthread_mutex_trylock.c new file mode 100644 index 00000000..1e3817bb --- /dev/null +++ b/src/thread/pthread_mutex_trylock.c @@ -0,0 +1,28 @@ +#include "pthread_impl.h" + +int pthread_mutex_trylock(pthread_mutex_t *m) +{ + if (m->__type == PTHREAD_MUTEX_RECURSIVE) { + pthread_t self = pthread_self(); + if (m->__owner == self) { + if ((unsigned)m->__lock >= INT_MAX) return EAGAIN; + a_inc(&m->__lock); + return 0; + } + if (a_fetch_add(&m->__lock, 1)) { + if (a_fetch_add(&m->__lock, -1)==1 && m->__waiters) + __wake(&m->__lock, 1, 0); + return EBUSY; + } + m->__owner = self; + return 0; + } + + if (a_xchg(&m->__lock, 1)) + if (m->__type == PTHREAD_MUTEX_ERRORCHECK + && m->__owner == pthread_self()) return EDEADLK; + else return EBUSY; + if (m->__type == PTHREAD_MUTEX_ERRORCHECK) + m->__owner = pthread_self(); + return 0; +} -- cgit v1.2.1