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support, build/test tooling, and documentation.

tests/unit/test_scheduler.c

@@ -0,0 +1,214 @@
+/**
+ * @file test_scheduler.c
+ * @brief Unit tests for scheduler
+ */
+
+#include "unity.h"
+#include "kernel.h"
+#include "scheduler.h"
+#include "task.h"
+#include <string.h>
+
+/* Test task handles */
+static TaskHandle_t test_tasks[10];
+static volatile uint32_t task_execution_count[10];
+static volatile uint32_t task_execution_order[100];
+static volatile uint32_t execution_index = 0;
+
+/* Test task functions */
+static void test_task_0(void* params) {
+    (void)params;
+    while (1) {
+        task_execution_count[0]++;
+        task_execution_order[execution_index++] = 0;
+        kernel_delay(10);
+    }
+}
+
+static void test_task_1(void* params) {
+    (void)params;
+    while (1) {
+        task_execution_count[1]++;
+        task_execution_order[execution_index++] = 1;
+        kernel_delay(20);
+    }
+}
+
+static void test_task_2(void* params) {
+    (void)params;
+    while (1) {
+        task_execution_count[2]++;
+        task_execution_order[execution_index++] = 2;
+        kernel_delay(50);
+    }
+}
+
+/* Test Setup */
+void setUp(void) {
+    /* Reset test state */
+    memset((void*)task_execution_count, 0, sizeof(task_execution_count));
+    execution_index = 0;
+
+    /* Initialize kernel */
+    kernel_init();
+}
+
+/* Test Teardown */
+void tearDown(void) {
+    /* Stop kernel */
+    kernel_stop();
+}
+
+/* ============================================================================
+ * Test Cases
+ * ============================================================================ */
+
+/**
+ * @brief Test scheduler initialization
+ */
+void test_scheduler_init(void) {
+    SchedulerConfig_t config = {
+        .type = SCHEDULER_PRIORITY_PREEMPTIVE,
+        .time_slice_ticks = 10,
+        .enable_deadline_monitoring = true
+    };
+
+    scheduler_init(&config);
+
+    /* Verify scheduler is initialized */
+    TEST_ASSERT_NOT_NULL(scheduler_get_current_task());
+}
+
+/**
+ * @brief Test task creation and scheduling
+ */
+void test_task_creation(void) {
+    TaskConfig_t config = {
+        .name = "test_task",
+        .function = test_task_0,
+        .parameters = NULL,
+        .stack_size = 1024,
+        .priority = 1,
+        .period_ticks = 0
+    };
+
+    test_tasks[0] = task_create(&config);
+
+    TEST_ASSERT_NOT_NULL(test_tasks[0]);
+    TEST_ASSERT_EQUAL(1, task_get_priority(test_tasks[0]));
+    TEST_ASSERT_EQUAL(TASK_READY, task_get_state(test_tasks[0]));
+}
+
+/**
+ * @brief Test priority-based scheduling
+ */
+void test_priority_scheduling(void) {
+    /* Create tasks with different priorities */
+    TaskConfig_t config1 = {
+        .name = "high_priority",
+        .function = test_task_0,
+        .parameters = NULL,
+        .stack_size = 1024,
+        .priority = 0,
+        .period_ticks = 10
+    };
+
+    TaskConfig_t config2 = {
+        .name = "low_priority",
+        .function = test_task_1,
+        .parameters = NULL,
+        .stack_size = 1024,
+        .priority = 5,
+        .period_ticks = 10
+    };
+
+    test_tasks[0] = task_create(&config1);
+    test_tasks[1] = task_create(&config2);
+
+    /* Start kernel */
+    kernel_start();
+
+    /* Let tasks run for 100ms */
+    kernel_delay(100);
+
+    /* High priority task should execute more */
+    TEST_ASSERT_GREATER_THAN(task_execution_count[1], task_execution_count[0]);
+}
+
+/**
+ * @brief Test round-robin scheduling
+ */
+void test_round_robin_scheduling(void) {
+    /* Create two tasks with same priority */
+    TaskConfig_t config1 = {
+        .name = "task_a",
+        .function = test_task_0,
+        .parameters = NULL,
+        .stack_size = 1024,
+        .priority = 3,
+        .period_ticks = 0
+    };
+
+    TaskConfig_t config2 = {
+        .name = "task_b",
+        .function = test_task_1,
+        .parameters = NULL,
+        .stack_size = 1024,
+        .priority = 3,
+        .period_ticks = 0
+    };
+
+    test_tasks[0] = task_create(&config1);
+    test_tasks[1] = task_create(&config2);
+
+    kernel_start();
+    kernel_delay(100);
+
+    /* Both tasks should execute */
+    TEST_ASSERT_GREATER_THAN(0, task_execution_count[0]);
+    TEST_ASSERT_GREATER_THAN(0, task_execution_count[1]);
+}
+
+/**
+ * @brief Test scheduler statistics
+ */
+void test_scheduler_statistics(void) {
+    SchedulerStatistics_t stats;
+
+    scheduler_get_statistics(&stats);
+
+    TEST_ASSERT_GREATER_THAN(0, stats.context_switches);
+    TEST_ASSERT_GREATER_OR_EQUAL(0, stats.preemptions);
+}
+
+/**
+ * @brief Test scheduler lock/unlock
+ */
+void test_scheduler_lock_unlock(void) {
+    /* Lock scheduler */
+    scheduler_lock();
+
+    /* Try to yield */
+    scheduler_yield();
+
+    /* Unlock scheduler */
+    scheduler_unlock();
+
+    TEST_ASSERT_TRUE(true);
+}
+
+/* ============================================================================
+ * Test Runner
+ * ============================================================================ */
+int main(void) {
+    UNITY_BEGIN();
+
+    RUN_TEST(test_scheduler_init);
+    RUN_TEST(test_task_creation);
+    RUN_TEST(test_priority_scheduling);
+    RUN_TEST(test_round_robin_scheduling);
+    RUN_TEST(test_scheduler_statistics);
+    RUN_TEST(test_scheduler_lock_unlock);
+
+    return UNITY_END();
+}