3 files changed, 96 insertions, 2 deletions

diff --git a/source/kit/shared_mutex.h b/source/kit/shared_mutex.h
index d202090..ad83418 100644
--- a/source/kit/shared_mutex.h
+++ b/source/kit/shared_mutex.h
@@ -47,7 +47,7 @@ static void kit_shared_mutex_init(kit_shared_mutex_t *m) {
                         memory_order_relaxed);
 }
 
-static i8 kit_shared_try_lock(kit_shared_mutex_t *m) {
+static b8 kit_shared_try_lock(kit_shared_mutex_t *m) {
   assert(m != NULL);
 
   for (;;) {
@@ -108,7 +108,7 @@ static void kit_shared_unlock(kit_shared_mutex_t *m) {
     assert(0);
 }
 
-static i8 kit_unique_try_lock(kit_shared_mutex_t *m) {
+static b8 kit_unique_try_lock(kit_shared_mutex_t *m) {
   assert(m != NULL);
 
   i8 prev_state = KIT_SHARED_MUTEX_READY;
diff --git a/source/tests/_exe.c b/source/tests/_exe.c
index 5509ab3..acbe5c2 100644
--- a/source/tests/_exe.c
+++ b/source/tests/_exe.c
@@ -15,6 +15,7 @@
 #include "astar.test.c"
 #include "move_back.test.c"
 #include "mutex.test.c"
+#include "shared_mutex.test.c"
 #include "secure_random.test.c"
 #include "sha256.test.c"
 #include "string_ref.test.c"
diff --git a/source/tests/shared_mutex.test.c b/source/tests/shared_mutex.test.c
new file mode 100644
index 0000000..9ee999b
--- /dev/null
+++ b/source/tests/shared_mutex.test.c
@@ -0,0 +1,93 @@
+#include "../kit/shared_mutex.h"
+#include "../kit/threads.h"
+
+#define KIT_TEST_FILE shared_mutex
+#include "../kit/test.h"
+
+enum {
+  SHARED_MUTEX_TEST_SLEEP        = 400000000,
+  SHARED_MUTEX_TEST_TICK_COUNT   = 200,
+  SHARED_MUTEX_TEST_THREAD_COUNT = 100,
+};
+
+typedef struct {
+  shared_mutex_t lock;
+  int            value;
+} shared_mutex_test_data_t;
+
+static int shared_mutex_test_run_(void *data) {
+  shared_mutex_test_data_t *x = (shared_mutex_test_data_t *) data;
+
+  for (i64 i = 0; i < SHARED_MUTEX_TEST_TICK_COUNT; i++) {
+    unique_lock(&x->lock);
+
+    x->value += i;
+    thrd_yield();
+    x->value -= i + 42;
+    thrd_yield();
+    x->value += i + 20;
+    thrd_yield();
+    x->value += 22 - i;
+
+    unique_unlock(&x->lock);
+  }
+
+  return 0;
+}
+
+TEST("shared mutex lock") {
+  shared_mutex_test_data_t data;
+  thrd_t                   pool[SHARED_MUTEX_TEST_THREAD_COUNT];
+
+  data.value = 42;
+  shared_mutex_init(&data.lock);
+
+  for (i64 i = 0; i < SHARED_MUTEX_TEST_THREAD_COUNT; i++)
+    thrd_create(pool + i, shared_mutex_test_run_, &data);
+  for (i64 i = 0; i < SHARED_MUTEX_TEST_THREAD_COUNT; i++)
+    thrd_join(pool[i], NULL);
+
+  REQUIRE(data.value == 42);
+}
+
+static int shared_mutex_test_lock_(void *data) {
+  shared_mutex_t *m = (shared_mutex_t *) data;
+  unique_lock(m);
+
+  thrd_sleep(
+      &(struct timespec) {
+          .tv_sec  = 0,
+          .tv_nsec = SHARED_MUTEX_TEST_SLEEP,
+      },
+      NULL);
+
+  unique_unlock(m);
+
+  return 0;
+}
+
+TEST("shared mutex try lock") {
+  shared_mutex_t m;
+  shared_mutex_init(&m);
+
+  thrd_t t;
+  REQUIRE_EQ(thrd_create(&t, shared_mutex_test_lock_, &m),
+             thrd_success);
+
+  REQUIRE_EQ(thrd_sleep(
+                 &(struct timespec) {
+                     .tv_sec  = 0,
+                     .tv_nsec = SHARED_MUTEX_TEST_SLEEP / 2,
+                 },
+                 NULL),
+             thrd_success);
+
+  REQUIRE_EQ(shared_try_lock(&m), 0);
+
+  REQUIRE_EQ(thrd_join(t, NULL), thrd_success);
+
+  REQUIRE_EQ(shared_try_lock(&m), 1);
+  shared_unlock(&m);
+}
+
+#undef KIT_TEST_FILE