/* coroutine_sema.h - Simple semaphores for coroutine.{h,c}
 *
 * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
 * SPDX-Licence-Identifier: AGPL-3.0-or-later
 */

#ifndef _COROUTINE_SEMA_H_
#define _COROUTINE_SEMA_H_

/**
 * A cr_sema_t is a fair unbounded[1] counting semaphore.
 *
 * [1]: Well, INT_MAX
 */
typedef struct sema_t cr_sema_t;

/**
 * Increment the semaphore,
 *
 * @blocks never
 * @yields never
 * @run_in anywhere (coroutine, sighandler)
 */
void cr_sema_signal(cr_sema_t *sema);

/**
 * Wait until the semaphore is >0, then decrement it.
 *
 * @blocks maybe
 * @yields maybe
 * @may_run_in coroutine
 */
void cr_sema_wait(cr_sema_t *sema);

#endif /* _COROUTINE_SEMA_H_ */