/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (c) 2023 Meta Platforms, Inc. and affiliates.
 * Copyright (c) 2023 Tejun Heo <tj@kernel.org>
 * Copyright (c) 2023 David Vernet <dvernet@meta.com>
 */

#ifndef __SCX_TEST_H__
#define __SCX_TEST_H__

#include <errno.h>
#include <scx/common.h>
#include <scx/compat.h>

enum scx_test_status {
	SCX_TEST_PASS = 0,
	SCX_TEST_SKIP,
	SCX_TEST_FAIL,
};

#define EXIT_KIND(__ent) __COMPAT_ENUM_OR_ZERO("scx_exit_kind", #__ent)

struct scx_test {
	/**
	 * name - The name of the testcase.
	 */
	const char *name;

	/**
	 * description - A description of your testcase: what it tests and is
	 * meant to validate.
	 */
	const char *description;

	/*
	 * setup - Setup the test.
	 * @ctx: A pointer to a context object that will be passed to run and
	 *	 cleanup.
	 *
	 * An optional callback that allows a testcase to perform setup for its
	 * run. A test may return SCX_TEST_SKIP to skip the run.
	 */
	enum scx_test_status (*setup)(void **ctx);

	/*
	 * run - Run the test.
	 * @ctx: Context set in the setup() callback. If @ctx was not set in
	 *	 setup(), it is NULL.
	 *
	 * The main test. Callers should return one of:
	 *
	 * - SCX_TEST_PASS: Test passed
	 * - SCX_TEST_SKIP: Test should be skipped
	 * - SCX_TEST_FAIL: Test failed
	 *
	 * This callback must be defined.
	 */
	enum scx_test_status (*run)(void *ctx);

	/*
	 * cleanup - Perform cleanup following the test
	 * @ctx: Context set in the setup() callback. If @ctx was not set in
	 *	 setup(), it is NULL.
	 *
	 * An optional callback that allows a test to perform cleanup after
	 * being run. This callback is run even if the run() callback returns
	 * SCX_TEST_SKIP or SCX_TEST_FAIL. It is not run if setup() returns
	 * SCX_TEST_SKIP or SCX_TEST_FAIL.
	 */
	void (*cleanup)(void *ctx);
};

void scx_test_register(struct scx_test *test);

#define REGISTER_SCX_TEST(__test)			\
	__attribute__((constructor))			\
	static void ___scxregister##__LINE__(void)	\
	{						\
		scx_test_register(__test);		\
	}

#define SCX_ERR(__fmt, ...)						\
	do {								\
		fprintf(stderr, "ERR: %s:%d\n", __FILE__, __LINE__);	\
		fprintf(stderr, __fmt"\n", ##__VA_ARGS__);			\
	} while (0)

#define SCX_FAIL(__fmt, ...)						\
	do {								\
		SCX_ERR(__fmt, ##__VA_ARGS__);				\
		return SCX_TEST_FAIL;					\
	} while (0)

#define SCX_FAIL_IF(__cond, __fmt, ...)					\
	do {								\
		if (__cond)						\
			SCX_FAIL(__fmt, ##__VA_ARGS__);			\
	} while (0)

#define SCX_GT(_x, _y) SCX_FAIL_IF((_x) <= (_y), "Expected %s > %s (%lu > %lu)",	\
				   #_x, #_y, (u64)(_x), (u64)(_y))
#define SCX_GE(_x, _y) SCX_FAIL_IF((_x) < (_y), "Expected %s >= %s (%lu >= %lu)",	\
				   #_x, #_y, (u64)(_x), (u64)(_y))
#define SCX_LT(_x, _y) SCX_FAIL_IF((_x) >= (_y), "Expected %s < %s (%lu < %lu)",	\
				   #_x, #_y, (u64)(_x), (u64)(_y))
#define SCX_LE(_x, _y) SCX_FAIL_IF((_x) > (_y), "Expected %s <= %s (%lu <= %lu)",	\
				   #_x, #_y, (u64)(_x), (u64)(_y))
#define SCX_EQ(_x, _y) SCX_FAIL_IF((_x) != (_y), "Expected %s == %s (%lu == %lu)",	\
				   #_x, #_y, (u64)(_x), (u64)(_y))
#define SCX_ASSERT(_x) SCX_FAIL_IF(!(_x), "Expected %s to be true (%lu)",		\
				   #_x, (u64)(_x))

#define SCX_ECODE_VAL(__ecode) ({						\
        u64 __val = 0;								\
	bool __found = false;							\
										\
	__found = __COMPAT_read_enum("scx_exit_code", #__ecode, &__val);	\
	SCX_ASSERT(__found);							\
	(s64)__val;								\
})

#define SCX_KIND_VAL(__kind) ({							\
        u64 __val = 0;								\
	bool __found = false;							\
										\
	__found = __COMPAT_read_enum("scx_exit_kind", #__kind, &__val);		\
	SCX_ASSERT(__found);							\
	__val;									\
})

#endif  // # __SCX_TEST_H__