misc

2 files changed, 51 insertions, 1 deletions

diff --git a/libcr_ipc/include/libcr_ipc/mutex.h b/libcr_ipc/include/libcr_ipc/mutex.h
new file mode 100644
index 0000000..38ebde0
--- /dev/null
+++ b/libcr_ipc/include/libcr_ipc/mutex.h
@@ -0,0 +1,46 @@
+/* libcr_ipc/mutex.h - Simple mutexes for libcr (header file)
+ *
+ * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
+ * SPDX-Licence-Identifier: AGPL-3.0-or-later
+ */
+
+#ifndef _COROUTINE_MUTEX_H_
+#define _COROUTINE_MUTEX_H_
+
+#include <stdbool.h> /* for bool */
+
+#include <libcr/coroutine.h> /* for cid_t */
+
+struct _cr_mutex_cid_list {
+	cid_t                            val;
+	struct _cr_mutex_cid_list        *next;
+};
+
+/**
+ * A cr_mutex_t is a fair mutex.
+ */
+typedef struct {
+	bool                             locked;
+	struct _cr_mutex_cid_list        *head, **tail;
+} cr_mutex_t;
+
+/**
+ * Lock the mutex.  Blocks if it is already locked.
+ *
+ * @blocks maybe
+ * @yields maybe
+ * @run_in coroutine
+ */
+void cr_mutex_lock(cr_mutex_t *);
+
+/**
+ * Unlock the mutex.  Unblocks a coroutine that is blocked on
+ * cr_mutex_lock().
+ *
+ * @blocks never
+ * @yields never
+ * @may_run_in coroutine
+ */
+void cr_mutex_unluck(cr_mutex_t *);
+
+#endif /* _COROUTINE_MUTEX_H_ */
diff --git a/libcr_ipc/include/libcr_ipc/sema.h b/libcr_ipc/include/libcr_ipc/sema.h
index a2a176d..454eb5d 100644
--- a/libcr_ipc/include/libcr_ipc/sema.h
+++ b/libcr_ipc/include/libcr_ipc/sema.h
@@ -1,4 +1,4 @@
-/* coroutine_sema.h - Simple semaphores for coroutine.{h,c}
+/* libcr_ipc/sema.h - Simple semaphores for libcr (header file)
  *
  * Copyright (C) 2024  Luke T. Shumaker <lukeshu@lukeshu.com>
  * SPDX-Licence-Identifier: AGPL-3.0-or-later
@@ -7,6 +7,10 @@
 #ifndef _COROUTINE_SEMA_H_
 #define _COROUTINE_SEMA_H_
 
+#include <stdbool.h> /* for bool */
+
+#include <libcr/coroutine.h> /* for cid_t */
+
 struct _cr_sema_cid_list {
 	cid_t                            val;
 	struct _cr_sema_cid_list        *next;