semaphore: add sem_value() helper function

This function returns current value of the semaphore. Signed-off-by: Pawel Wieczorkiewicz <[email protected]>
KernelTestFramework · Aug 6, 2021 · ced3149 · ced3149
1 parent 633a57f
commit ced3149
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Showing 2 changed files with 5 additions and 1 deletion.
diff --git a/include/semaphore.h b/include/semaphore.h
@@ -39,6 +39,8 @@ typedef struct sem sem_t;
         .v = {(value) }                                                                  \
     }
 
+extern int32_t sem_value(const sem_t *sem);
+
 extern void sem_init(sem_t *sem, uint32_t value);
 extern bool sem_trywait(sem_t *sem);
 extern void sem_wait(sem_t *sem);

diff --git a/lib/semaphore.c b/lib/semaphore.c
@@ -33,10 +33,12 @@ void sem_init(sem_t *sem, uint32_t value) {
     atomic_set(&(sem->v), value);
 }
 
+int32_t sem_value(const sem_t *sem) { return atomic_read(&sem->v); }
+
 bool sem_trywait(sem_t *sem) {
     int64_t val;
 
-    if (atomic_read(&(sem->v)) > 0) {
+    if (sem_value(sem) > 0) {
         val = atomic_dec_return(&(sem->v));
         if (val >= 0) {
             return true;