1 files changed, 89 insertions, 0 deletions
diff --git a/src/posix/sem_posix.c b/src/posix/sem_posix.c
new file mode 100644
index 0000000..452830d
--- /dev/null
+++ b/src/posix/sem_posix.c
@@ -0,0 +1,89 @@
+// Copyright 2012-2022 David Robillard <d@drobilla.net>
+// SPDX-License-Identifier: ISC
+
+#include "zix/sem.h"
+
+#include "../errno_status.h"
+#include "../zix_config.h"
+
+#include "zix/status.h"
+
+#include <semaphore.h>
+
+#include <errno.h>
+#include <stdint.h>
+#include <time.h>
+
+ZixStatus
+zix_sem_init(ZixSem* sem, unsigned initial)
+{
+  return zix_errno_status_if(sem_init(&sem->sem, 0, initial));
+}
+
+ZixStatus
+zix_sem_destroy(ZixSem* sem)
+{
+  return zix_errno_status_if(sem_destroy(&sem->sem));
+}
+
+ZixStatus
+zix_sem_post(ZixSem* sem)
+{
+  return zix_errno_status_if(sem_post(&sem->sem));
+}
+
+ZixStatus
+zix_sem_wait(ZixSem* sem)
+{
+  int r = 0;
+  while ((r = sem_wait(&sem->sem)) && errno == EINTR) {
+    // Interrupted, try again
+  }
+
+  return zix_errno_status_if(r);
+}
+
+ZixStatus
+zix_sem_try_wait(ZixSem* sem)
+{
+  int r = 0;
+  while ((r = sem_trywait(&sem->sem)) && errno == EINTR) {
+    // Interrupted, try again
+  }
+
+  return zix_errno_status_if(r);
+}
+
+ZixStatus
+zix_sem_timed_wait(ZixSem*        sem,
+                   const uint32_t seconds,
+                   const uint32_t nanoseconds)
+{
+#if !USE_CLOCK_GETTIME || !USE_SEM_TIMEDWAIT
+
+  return ZIX_STATUS_NOT_SUPPORTED;
+
+#else
+#  define NS_PER_SECOND 1000000000L
+
+  struct timespec ts = {0, 0};
+
+  int r = 0;
+  if (!(r = clock_gettime(CLOCK_REALTIME, &ts))) {
+    ts.tv_sec += (time_t)seconds;
+    ts.tv_nsec += (long)nanoseconds;
+    if (ts.tv_nsec >= NS_PER_SECOND) {
+      ts.tv_nsec -= NS_PER_SECOND;
+      ts.tv_sec++;
+    }
+
+    while ((r = sem_timedwait(&sem->sem, &ts)) && errno == EINTR) {
+      // Interrupted, try again
+    }
+  }
+
+  return zix_errno_status_if(r);
+
+#  undef NS_PER_SECOND
+#endif
+}