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tests/unit/test_mutex.c

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+/**
+ * @file test_mutex.c
+ * @brief Unit tests for mutex
+ */
+
+#include "unity.h"
+#include "kernel.h"
+#include "mutex.h"
+#include "task.h"
+#include <string.h>
+
+/* Test mutexes */
+static Mutex_t test_mutex;
+static Mutex_t recursive_mutex;
+
+/* Test task for mutex contention */
+static TaskHandle_t contention_task;
+static volatile bool task_got_mutex = false;
+
+static void mutex_contention_task(void* params) {
+    (void)params;
+
+    /* Try to lock mutex */
+    if (mutex_lock(&test_mutex, 1000) == KERNEL_OK) {
+        task_got_mutex = true;
+        mutex_unlock(&test_mutex);
+    }
+
+    while (1) {
+        kernel_delay(1000);
+    }
+}
+
+/* Setup */
+void setUp(void) {
+    kernel_init();
+
+    /* Create test mutexes */
+    mutex_create(&test_mutex, false);
+    mutex_create(&recursive_mutex, true);
+
+    task_got_mutex = false;
+}
+
+/* Teardown */
+void tearDown(void) {
+    kernel_stop();
+}
+
+/* ============================================================================
+ * Test Cases
+ * ============================================================================ */
+
+/**
+ * @brief Test mutex creation
+ */
+void test_mutex_create(void) {
+    TEST_ASSERT_NULL(mutex_get_owner(&test_mutex));
+}
+
+/**
+ * @brief Test mutex lock and unlock
+ */
+void test_mutex_lock_unlock(void) {
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_lock(&test_mutex, 100));
+    TEST_ASSERT_NOT_NULL(mutex_get_owner(&test_mutex));
+
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_unlock(&test_mutex));
+    TEST_ASSERT_NULL(mutex_get_owner(&test_mutex));
+}
+
+/**
+ * @brief Test recursive mutex
+ */
+void test_recursive_mutex(void) {
+    /* Lock recursive mutex multiple times */
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_lock(&recursive_mutex, 100));
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_lock(&recursive_mutex, 100));
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_lock(&recursive_mutex, 100));
+
+    /* Unlock same number of times */
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_unlock(&recursive_mutex));
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_unlock(&recursive_mutex));
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_unlock(&recursive_mutex));
+}
+
+/**
+ * @brief Test non-recursive mutex
+ */
+void test_non_recursive_mutex(void) {
+    /* Lock mutex */
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_lock(&test_mutex, 100));
+
+    /* Try to lock again */
+    TEST_ASSERT_EQUAL(KERNEL_RESOURCE_BUSY, mutex_lock(&test_mutex, 0));
+
+    /* Unlock */
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_unlock(&test_mutex));
+}
+
+/**
+ * @brief Test mutex timeout
+ */
+void test_mutex_timeout(void) {
+    /* Lock mutex */
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_lock(&test_mutex, 0));
+
+    /* Create contention task */
+    TaskConfig_t config = {
+        .name = "contention",
+        .function = mutex_contention_task,
+        .parameters = NULL,
+        .stack_size = 1024,
+        .priority = 1,
+        .period_ticks = 0
+    };
+
+    contention_task = task_create(&config);
+
+    kernel_start();
+    kernel_delay(100);
+
+    /* Task should not have gotten mutex yet */
+    TEST_ASSERT_FALSE(task_got_mutex);
+
+    /* Unlock mutex */
+    mutex_unlock(&test_mutex);
+
+    kernel_delay(100);
+
+    /* Task should have gotten mutex */
+    TEST_ASSERT_TRUE(task_got_mutex);
+}
+
+/**
+ * @brief Test mutex deletion
+ */
+void test_mutex_delete(void) {
+    TEST_ASSERT_EQUAL(KERNEL_OK, mutex_delete(&test_mutex));
+}
+
+/* ============================================================================
+ * Test Runner
+ * ============================================================================ */
+int main(void) {
+    UNITY_BEGIN();
+
+    RUN_TEST(test_mutex_create);
+    RUN_TEST(test_mutex_lock_unlock);
+    RUN_TEST(test_recursive_mutex);
+    RUN_TEST(test_non_recursive_mutex);
+    RUN_TEST(test_mutex_timeout);
+    RUN_TEST(test_mutex_delete);
+
+    return UNITY_END();
+}