summaryrefslogtreecommitdiff
path: root/tools/testing/selftests/kselftest_harness.h
blob: 2902f6a78f8a313fa1da2511984bc47579a46916 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
 *
 * kselftest_harness.h: simple C unit test helper.
 *
 * See documentation in Documentation/dev-tools/kselftest.rst
 *
 * API inspired by code.google.com/p/googletest
 */

/**
 * DOC: example
 *
 * .. code-block:: c
 *
 *    #include "../kselftest_harness.h"
 *
 *    TEST(standalone_test) {
 *      do_some_stuff;
 *      EXPECT_GT(10, stuff) {
 *         stuff_state_t state;
 *         enumerate_stuff_state(&state);
 *         TH_LOG("expectation failed with state: %s", state.msg);
 *      }
 *      more_stuff;
 *      ASSERT_NE(some_stuff, NULL) TH_LOG("how did it happen?!");
 *      last_stuff;
 *      EXPECT_EQ(0, last_stuff);
 *    }
 *
 *    FIXTURE(my_fixture) {
 *      mytype_t *data;
 *      int awesomeness_level;
 *    };
 *    FIXTURE_SETUP(my_fixture) {
 *      self->data = mytype_new();
 *      ASSERT_NE(NULL, self->data);
 *    }
 *    FIXTURE_TEARDOWN(my_fixture) {
 *      mytype_free(self->data);
 *    }
 *    TEST_F(my_fixture, data_is_good) {
 *      EXPECT_EQ(1, is_my_data_good(self->data));
 *    }
 *
 *    TEST_HARNESS_MAIN
 */

#ifndef __KSELFTEST_HARNESS_H
#define __KSELFTEST_HARNESS_H

#define _GNU_SOURCE
#include <asm/types.h>
#include <errno.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>

#define TEST_TIMEOUT_DEFAULT 30

/* Utilities exposed to the test definitions */
#ifndef TH_LOG_STREAM
#  define TH_LOG_STREAM stderr
#endif

#ifndef TH_LOG_ENABLED
#  define TH_LOG_ENABLED 1
#endif

/**
 * TH_LOG(fmt, ...)
 *
 * @fmt: format string
 * @...: optional arguments
 *
 * .. code-block:: c
 *
 *     TH_LOG(format, ...)
 *
 * Optional debug logging function available for use in tests.
 * Logging may be enabled or disabled by defining TH_LOG_ENABLED.
 * E.g., #define TH_LOG_ENABLED 1
 *
 * If no definition is provided, logging is enabled by default.
 *
 * If there is no way to print an error message for the process running the
 * test (e.g. not allowed to write to stderr), it is still possible to get the
 * ASSERT_* number for which the test failed.  This behavior can be enabled by
 * writing `_metadata->no_print = true;` before the check sequence that is
 * unable to print.  When an error occur, instead of printing an error message
 * and calling `abort(3)`, the test process call `_exit(2)` with the assert
 * number as argument, which is then printed by the parent process.
 */
#define TH_LOG(fmt, ...) do { \
	if (TH_LOG_ENABLED) \
		__TH_LOG(fmt, ##__VA_ARGS__); \
} while (0)

/* Unconditional logger for internal use. */
#define __TH_LOG(fmt, ...) \
		fprintf(TH_LOG_STREAM, "%s:%d:%s:" fmt "\n", \
			__FILE__, __LINE__, _metadata->name, ##__VA_ARGS__)

/**
 * XFAIL(statement, fmt, ...)
 *
 * @statement: statement to run after reporting XFAIL
 * @fmt: format string
 * @...: optional arguments
 *
 * This forces a "pass" after reporting a failure with an XFAIL prefix,
 * and runs "statement", which is usually "return" or "goto skip".
 */
#define XFAIL(statement, fmt, ...) do { \
	if (TH_LOG_ENABLED) { \
		fprintf(TH_LOG_STREAM, "[  XFAIL!  ] " fmt "\n", \
			##__VA_ARGS__); \
	} \
	/* TODO: find a way to pass xfail to test runner process. */ \
	_metadata->passed = 1; \
	_metadata->trigger = 0; \
	statement; \
} while (0)

/**
 * TEST(test_name) - Defines the test function and creates the registration
 * stub
 *
 * @test_name: test name
 *
 * .. code-block:: c
 *
 *     TEST(name) { implementation }
 *
 * Defines a test by name.
 * Names must be unique and tests must not be run in parallel.  The
 * implementation containing block is a function and scoping should be treated
 * as such.  Returning early may be performed with a bare "return;" statement.
 *
 * EXPECT_* and ASSERT_* are valid in a TEST() { } context.
 */
#define TEST(test_name) __TEST_IMPL(test_name, -1)

/**
 * TEST_SIGNAL(test_name, signal)
 *
 * @test_name: test name
 * @signal: signal number
 *
 * .. code-block:: c
 *
 *     TEST_SIGNAL(name, signal) { implementation }
 *
 * Defines a test by name and the expected term signal.
 * Names must be unique and tests must not be run in parallel.  The
 * implementation containing block is a function and scoping should be treated
 * as such.  Returning early may be performed with a bare "return;" statement.
 *
 * EXPECT_* and ASSERT_* are valid in a TEST() { } context.
 */
#define TEST_SIGNAL(test_name, signal) __TEST_IMPL(test_name, signal)

#define __TEST_IMPL(test_name, _signal) \
	static void test_name(struct __test_metadata *_metadata); \
	static struct __test_metadata _##test_name##_object = \
		{ .name = "global." #test_name, \
		  .fn = &test_name, .termsig = _signal, \
		  .timeout = TEST_TIMEOUT_DEFAULT, }; \
	static void __attribute__((constructor)) _register_##test_name(void) \
	{ \
		__register_test(&_##test_name##_object); \
	} \
	static void test_name( \
		struct __test_metadata __attribute__((unused)) *_metadata)

/**
 * FIXTURE_DATA(datatype_name) - Wraps the struct name so we have one less
 * argument to pass around
 *
 * @datatype_name: datatype name
 *
 * .. code-block:: c
 *
 *     FIXTURE_DATA(datatype name)
 *
 * This call may be used when the type of the fixture data
 * is needed.  In general, this should not be needed unless
 * the *self* is being passed to a helper directly.
 */
#define FIXTURE_DATA(datatype_name) struct _test_data_##datatype_name

/**
 * FIXTURE(fixture_name) - Called once per fixture to setup the data and
 * register
 *
 * @fixture_name: fixture name
 *
 * .. code-block:: c
 *
 *     FIXTURE(datatype name) {
 *       type property1;
 *       ...
 *     };
 *
 * Defines the data provided to TEST_F()-defined tests as *self*.  It should be
 * populated and cleaned up using FIXTURE_SETUP() and FIXTURE_TEARDOWN().
 */
#define FIXTURE(fixture_name) \
	static void __attribute__((constructor)) \
	_register_##fixture_name##_data(void) \
	{ \
		__fixture_count++; \
	} \
	FIXTURE_DATA(fixture_name)

/**
 * FIXTURE_SETUP(fixture_name) - Prepares the setup function for the fixture.
 * *_metadata* is included so that EXPECT_* and ASSERT_* work correctly.
 *
 * @fixture_name: fixture name
 *
 * .. code-block:: c
 *
 *     FIXTURE_SETUP(fixture name) { implementation }
 *
 * Populates the required "setup" function for a fixture.  An instance of the
 * datatype defined with FIXTURE_DATA() will be exposed as *self* for the
 * implementation.
 *
 * ASSERT_* are valid for use in this context and will prempt the execution
 * of any dependent fixture tests.
 *
 * A bare "return;" statement may be used to return early.
 */
#define FIXTURE_SETUP(fixture_name) \
	void fixture_name##_setup( \
		struct __test_metadata __attribute__((unused)) *_metadata, \
		FIXTURE_DATA(fixture_name) __attribute__((unused)) *self)
/**
 * FIXTURE_TEARDOWN(fixture_name)
 * *_metadata* is included so that EXPECT_* and ASSERT_* work correctly.
 *
 * @fixture_name: fixture name
 *
 * .. code-block:: c
 *
 *     FIXTURE_TEARDOWN(fixture name) { implementation }
 *
 * Populates the required "teardown" function for a fixture.  An instance of the
 * datatype defined with FIXTURE_DATA() will be exposed as *self* for the
 * implementation to clean up.
 *
 * A bare "return;" statement may be used to return early.
 */
#define FIXTURE_TEARDOWN(fixture_name) \
	void fixture_name##_teardown( \
		struct __test_metadata __attribute__((unused)) *_metadata, \
		FIXTURE_DATA(fixture_name) __attribute__((unused)) *self)

/**
 * TEST_F(fixture_name, test_name) - Emits test registration and helpers for
 * fixture-based test cases
 *
 * @fixture_name: fixture name
 * @test_name: test name
 *
 * .. code-block:: c
 *
 *     TEST_F(fixture, name) { implementation }
 *
 * Defines a test that depends on a fixture (e.g., is part of a test case).
 * Very similar to TEST() except that *self* is the setup instance of fixture's
 * datatype exposed for use by the implementation.
 *
 * Warning: use of ASSERT_* here will skip TEARDOWN.
 */
/* TODO(wad) register fixtures on dedicated test lists. */
#define TEST_F(fixture_name, test_name) \
	__TEST_F_IMPL(fixture_name, test_name, -1, TEST_TIMEOUT_DEFAULT)

#define TEST_F_SIGNAL(fixture_name, test_name, signal) \
	__TEST_F_IMPL(fixture_name, test_name, signal, TEST_TIMEOUT_DEFAULT)

#define TEST_F_TIMEOUT(fixture_name, test_name, timeout) \
	__TEST_F_IMPL(fixture_name, test_name, -1, timeout)

#define __TEST_F_IMPL(fixture_name, test_name, signal, tmout) \
	static void fixture_name##_##test_name( \
		struct __test_metadata *_metadata, \
		FIXTURE_DATA(fixture_name) *self); \
	static inline void wrapper_##fixture_name##_##test_name( \
		struct __test_metadata *_metadata) \
	{ \
		/* fixture data is alloced, setup, and torn down per call. */ \
		FIXTURE_DATA(fixture_name) self; \
		memset(&self, 0, sizeof(FIXTURE_DATA(fixture_name))); \
		fixture_name##_setup(_metadata, &self); \
		/* Let setup failure terminate early. */ \
		if (!_metadata->passed) \
			return; \
		fixture_name##_##test_name(_metadata, &self); \
		fixture_name##_teardown(_metadata, &self); \
	} \
	static struct __test_metadata \
		      _##fixture_name##_##test_name##_object = { \
		.name = #fixture_name "." #test_name, \
		.fn = &wrapper_##fixture_name##_##test_name, \
		.termsig = signal, \
		.timeout = tmout, \
	 }; \
	static void __attribute__((constructor)) \
			_register_##fixture_name##_##test_name(void) \
	{ \
		__register_test(&_##fixture_name##_##test_name##_object); \
	} \
	static void fixture_name##_##test_name( \
		struct __test_metadata __attribute__((unused)) *_metadata, \
		FIXTURE_DATA(fixture_name) __attribute__((unused)) *self)

/**
 * TEST_HARNESS_MAIN - Simple wrapper to run the test harness
 *
 * .. code-block:: c
 *
 *     TEST_HARNESS_MAIN
 *
 * Use once to append a main() to the test file.
 */
#define TEST_HARNESS_MAIN \
	static void __attribute__((constructor)) \
	__constructor_order_last(void) \
	{ \
		if (!__constructor_order) \
			__constructor_order = _CONSTRUCTOR_ORDER_BACKWARD; \
	} \
	int main(int argc, char **argv) { \
		return test_harness_run(argc, argv); \
	}

/**
 * DOC: operators
 *
 * Operators for use in TEST() and TEST_F().
 * ASSERT_* calls will stop test execution immediately.
 * EXPECT_* calls will emit a failure warning, note it, and continue.
 */

/**
 * ASSERT_EQ(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_EQ(expected, measured): expected == measured
 */
#define ASSERT_EQ(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, ==, 1)

/**
 * ASSERT_NE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_NE(expected, measured): expected != measured
 */
#define ASSERT_NE(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, !=, 1)

/**
 * ASSERT_LT(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_LT(expected, measured): expected < measured
 */
#define ASSERT_LT(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, <, 1)

/**
 * ASSERT_LE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_LE(expected, measured): expected <= measured
 */
#define ASSERT_LE(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, <=, 1)

/**
 * ASSERT_GT(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_GT(expected, measured): expected > measured
 */
#define ASSERT_GT(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, >, 1)

/**
 * ASSERT_GE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_GE(expected, measured): expected >= measured
 */
#define ASSERT_GE(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, >=, 1)

/**
 * ASSERT_NULL(seen)
 *
 * @seen: measured value
 *
 * ASSERT_NULL(measured): NULL == measured
 */
#define ASSERT_NULL(seen) \
	__EXPECT(NULL, "NULL", seen, #seen, ==, 1)

/**
 * ASSERT_TRUE(seen)
 *
 * @seen: measured value
 *
 * ASSERT_TRUE(measured): measured != 0
 */
#define ASSERT_TRUE(seen) \
	__EXPECT(0, "0", seen, #seen, !=, 1)

/**
 * ASSERT_FALSE(seen)
 *
 * @seen: measured value
 *
 * ASSERT_FALSE(measured): measured == 0
 */
#define ASSERT_FALSE(seen) \
	__EXPECT(0, "0", seen, #seen, ==, 1)

/**
 * ASSERT_STREQ(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_STREQ(expected, measured): !strcmp(expected, measured)
 */
#define ASSERT_STREQ(expected, seen) \
	__EXPECT_STR(expected, seen, ==, 1)

/**
 * ASSERT_STRNE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * ASSERT_STRNE(expected, measured): strcmp(expected, measured)
 */
#define ASSERT_STRNE(expected, seen) \
	__EXPECT_STR(expected, seen, !=, 1)

/**
 * EXPECT_EQ(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_EQ(expected, measured): expected == measured
 */
#define EXPECT_EQ(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, ==, 0)

/**
 * EXPECT_NE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_NE(expected, measured): expected != measured
 */
#define EXPECT_NE(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, !=, 0)

/**
 * EXPECT_LT(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_LT(expected, measured): expected < measured
 */
#define EXPECT_LT(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, <, 0)

/**
 * EXPECT_LE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_LE(expected, measured): expected <= measured
 */
#define EXPECT_LE(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, <=, 0)

/**
 * EXPECT_GT(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_GT(expected, measured): expected > measured
 */
#define EXPECT_GT(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, >, 0)

/**
 * EXPECT_GE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_GE(expected, measured): expected >= measured
 */
#define EXPECT_GE(expected, seen) \
	__EXPECT(expected, #expected, seen, #seen, >=, 0)

/**
 * EXPECT_NULL(seen)
 *
 * @seen: measured value
 *
 * EXPECT_NULL(measured): NULL == measured
 */
#define EXPECT_NULL(seen) \
	__EXPECT(NULL, "NULL", seen, #seen, ==, 0)

/**
 * EXPECT_TRUE(seen)
 *
 * @seen: measured value
 *
 * EXPECT_TRUE(measured): 0 != measured
 */
#define EXPECT_TRUE(seen) \
	__EXPECT(0, "0", seen, #seen, !=, 0)

/**
 * EXPECT_FALSE(seen)
 *
 * @seen: measured value
 *
 * EXPECT_FALSE(measured): 0 == measured
 */
#define EXPECT_FALSE(seen) \
	__EXPECT(0, "0", seen, #seen, ==, 0)

/**
 * EXPECT_STREQ(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_STREQ(expected, measured): !strcmp(expected, measured)
 */
#define EXPECT_STREQ(expected, seen) \
	__EXPECT_STR(expected, seen, ==, 0)

/**
 * EXPECT_STRNE(expected, seen)
 *
 * @expected: expected value
 * @seen: measured value
 *
 * EXPECT_STRNE(expected, measured): strcmp(expected, measured)
 */
#define EXPECT_STRNE(expected, seen) \
	__EXPECT_STR(expected, seen, !=, 0)

#define ARRAY_SIZE(a)	(sizeof(a) / sizeof(a[0]))

/* Support an optional handler after and ASSERT_* or EXPECT_*.  The approach is
 * not thread-safe, but it should be fine in most sane test scenarios.
 *
 * Using __bail(), which optionally abort()s, is the easiest way to early
 * return while still providing an optional block to the API consumer.
 */
#define OPTIONAL_HANDLER(_assert) \
	for (; _metadata->trigger; _metadata->trigger = \
			__bail(_assert, _metadata->no_print, _metadata->step))

#define __INC_STEP(_metadata) \
	if (_metadata->passed && _metadata->step < 255) \
		_metadata->step++;

#define __EXPECT(_expected, _expected_str, _seen, _seen_str, _t, _assert) do { \
	/* Avoid multiple evaluation of the cases */ \
	__typeof__(_expected) __exp = (_expected); \
	__typeof__(_seen) __seen = (_seen); \
	if (_assert) __INC_STEP(_metadata); \
	if (!(__exp _t __seen)) { \
		unsigned long long __exp_print = (uintptr_t)__exp; \
		unsigned long long __seen_print = (uintptr_t)__seen; \
		__TH_LOG("Expected %s (%llu) %s %s (%llu)", \
			 _expected_str, __exp_print, #_t, \
			 _seen_str, __seen_print); \
		_metadata->passed = 0; \
		/* Ensure the optional handler is triggered */ \
		_metadata->trigger = 1; \
	} \
} while (0); OPTIONAL_HANDLER(_assert)

#define __EXPECT_STR(_expected, _seen, _t, _assert) do { \
	const char *__exp = (_expected); \
	const char *__seen = (_seen); \
	if (_assert) __INC_STEP(_metadata); \
	if (!(strcmp(__exp, __seen) _t 0))  { \
		__TH_LOG("Expected '%s' %s '%s'.", __exp, #_t, __seen); \
		_metadata->passed = 0; \
		_metadata->trigger = 1; \
	} \
} while (0); OPTIONAL_HANDLER(_assert)

/* Contains all the information for test execution and status checking. */
struct __test_metadata {
	const char *name;
	void (*fn)(struct __test_metadata *);
	pid_t pid;	/* pid of test when being run */
	int termsig;
	int passed;
	int trigger; /* extra handler after the evaluation */
	int timeout;	/* seconds to wait for test timeout */
	bool timed_out;	/* did this test timeout instead of exiting? */
	__u8 step;
	bool no_print; /* manual trigger when TH_LOG_STREAM is not available */
	struct __test_metadata *prev, *next;
};

/* Storage for the (global) tests to be run. */
static struct __test_metadata *__test_list;
static unsigned int __test_count;
static unsigned int __fixture_count;
static int __constructor_order;

#define _CONSTRUCTOR_ORDER_FORWARD   1
#define _CONSTRUCTOR_ORDER_BACKWARD -1

/*
 * Since constructors are called in reverse order, reverse the test
 * list so tests are run in source declaration order.
 * https://gcc.gnu.org/onlinedocs/gccint/Initialization.html
 * However, it seems not all toolchains do this correctly, so use
 * __constructor_order to detect which direction is called first
 * and adjust list building logic to get things running in the right
 * direction.
 */
static inline void __register_test(struct __test_metadata *t)
{
	__test_count++;
	/* Circular linked list where only prev is circular. */
	if (__test_list == NULL) {
		__test_list = t;
		t->next = NULL;
		t->prev = t;
		return;
	}
	if (__constructor_order == _CONSTRUCTOR_ORDER_FORWARD) {
		t->next = NULL;
		t->prev = __test_list->prev;
		t->prev->next = t;
		__test_list->prev = t;
	} else {
		t->next = __test_list;
		t->next->prev = t;
		t->prev = t;
		__test_list = t;
	}
}

static inline int __bail(int for_realz, bool no_print, __u8 step)
{
	if (for_realz) {
		if (no_print)
			_exit(step);
		abort();
	}
	return 0;
}

struct __test_metadata *__active_test;
static void __timeout_handler(int sig, siginfo_t *info, void *ucontext)
{
	struct __test_metadata *t = __active_test;

	/* Sanity check handler execution environment. */
	if (!t) {
		fprintf(TH_LOG_STREAM,
			"no active test in SIGARLM handler!?\n");
		abort();
	}
	if (sig != SIGALRM || sig != info->si_signo) {
		fprintf(TH_LOG_STREAM,
			"%s: SIGALRM handler caught signal %d!?\n",
			t->name, sig != SIGALRM ? sig : info->si_signo);
		abort();
	}

	t->timed_out = true;
	kill(t->pid, SIGKILL);
}

void __wait_for_test(struct __test_metadata *t)
{
	struct sigaction action = {
		.sa_sigaction = __timeout_handler,
		.sa_flags = SA_SIGINFO,
	};
	struct sigaction saved_action;
	int status;

	if (sigaction(SIGALRM, &action, &saved_action)) {
		t->passed = 0;
		fprintf(TH_LOG_STREAM,
			"%s: unable to install SIGARLM handler\n",
			t->name);
		return;
	}
	__active_test = t;
	t->timed_out = false;
	alarm(t->timeout);
	waitpid(t->pid, &status, 0);
	alarm(0);
	if (sigaction(SIGALRM, &saved_action, NULL)) {
		t->passed = 0;
		fprintf(TH_LOG_STREAM,
			"%s: unable to uninstall SIGARLM handler\n",
			t->name);
		return;
	}
	__active_test = NULL;

	if (t->timed_out) {
		t->passed = 0;
		fprintf(TH_LOG_STREAM,
			"%s: Test terminated by timeout\n", t->name);
	} else if (WIFEXITED(status)) {
		t->passed = t->termsig == -1 ? !WEXITSTATUS(status) : 0;
		if (t->termsig != -1) {
			fprintf(TH_LOG_STREAM,
				"%s: Test exited normally "
				"instead of by signal (code: %d)\n",
				t->name,
				WEXITSTATUS(status));
		} else if (!t->passed) {
			fprintf(TH_LOG_STREAM,
				"%s: Test failed at step #%d\n",
				t->name,
				WEXITSTATUS(status));
		}
	} else if (WIFSIGNALED(status)) {
		t->passed = 0;
		if (WTERMSIG(status) == SIGABRT) {
			fprintf(TH_LOG_STREAM,
				"%s: Test terminated by assertion\n",
				t->name);
		} else if (WTERMSIG(status) == t->termsig) {
			t->passed = 1;
		} else {
			fprintf(TH_LOG_STREAM,
				"%s: Test terminated unexpectedly "
				"by signal %d\n",
				t->name,
				WTERMSIG(status));
		}
	} else {
		fprintf(TH_LOG_STREAM,
			"%s: Test ended in some other way [%u]\n",
			t->name,
			status);
	}
}

void __run_test(struct __test_metadata *t)
{
	t->passed = 1;
	t->trigger = 0;
	printf("[ RUN      ] %s\n", t->name);
	t->pid = fork();
	if (t->pid < 0) {
		printf("ERROR SPAWNING TEST CHILD\n");
		t->passed = 0;
	} else if (t->pid == 0) {
		t->fn(t);
		/* return the step that failed or 0 */
		_exit(t->passed ? 0 : t->step);
	} else {
		__wait_for_test(t);
	}
	printf("[     %4s ] %s\n", (t->passed ? "OK" : "FAIL"), t->name);
}

static int test_harness_run(int __attribute__((unused)) argc,
			    char __attribute__((unused)) **argv)
{
	struct __test_metadata *t;
	int ret = 0;
	unsigned int count = 0;
	unsigned int pass_count = 0;

	/* TODO(wad) add optional arguments similar to gtest. */
	printf("[==========] Running %u tests from %u test cases.\n",
	       __test_count, __fixture_count + 1);
	for (t = __test_list; t; t = t->next) {
		count++;
		__run_test(t);
		if (t->passed)
			pass_count++;
		else
			ret = 1;
	}
	printf("[==========] %u / %u tests passed.\n", pass_count, count);
	printf("[  %s  ]\n", (ret ? "FAILED" : "PASSED"));
	return ret;
}

static void __attribute__((constructor)) __constructor_order_first(void)
{
	if (!__constructor_order)
		__constructor_order = _CONSTRUCTOR_ORDER_FORWARD;
}

#endif  /* __KSELFTEST_HARNESS_H */