From 4abab5ad6c8465a7528ccdd5f49367da05f78bbd Mon Sep 17 00:00:00 2001 From: Vladimir Azarov Date: Tue, 1 Oct 2024 15:47:05 +0200 Subject: Initial version --- src/thread/sem_post.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) create mode 100644 src/thread/sem_post.c (limited to 'src/thread/sem_post.c') diff --git a/src/thread/sem_post.c b/src/thread/sem_post.c new file mode 100644 index 0000000..5c2517f --- /dev/null +++ b/src/thread/sem_post.c @@ -0,0 +1,21 @@ +#include +#include +#include "pthread_impl.h" + +int sem_post(sem_t *sem) +{ + int val, new, waiters, priv = sem->__val[2]; + do { + val = sem->__val[0]; + waiters = sem->__val[1]; + if ((val & SEM_VALUE_MAX) == SEM_VALUE_MAX) { + errno = EOVERFLOW; + return -1; + } + new = val + 1; + if (waiters <= 1) + new &= ~0x80000000; + } while (a_cas(sem->__val, val, new) != val); + if (val<0) __wake(sem->__val, waiters>1 ? 1 : -1, priv); + return 0; +} -- cgit v1.2.3