1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * An API to allow a function, that may fail, to be executed, and recover in a
4 * controlled manner.
5 *
6 * Copyright (C) 2019, Google LLC.
7 * Author: Brendan Higgins <brendanhiggins@google.com>
8 */
9
10 #ifndef _KUNIT_TRY_CATCH_H
11 #define _KUNIT_TRY_CATCH_H
12
13 #include <linux/types.h>
14
15 typedef void (*kunit_try_catch_func_t)(void *);
16
17 struct completion;
18 struct kunit;
19
20 /**
21 * struct kunit_try_catch - provides a generic way to run code which might fail.
22 * @test: The test case that is currently being executed.
23 * @try_completion: Completion that the control thread waits on while test runs.
24 * @try_result: Contains any errno obtained while running test case.
25 * @try: The function, the test case, to attempt to run.
26 * @catch: The function called if @try bails out.
27 * @context: used to pass user data to the try and catch functions.
28 *
29 * kunit_try_catch provides a generic, architecture independent way to execute
30 * an arbitrary function of type kunit_try_catch_func_t which may bail out by
31 * calling kunit_try_catch_throw(). If kunit_try_catch_throw() is called, @try
32 * is stopped at the site of invocation and @catch is called.
33 *
34 * struct kunit_try_catch provides a generic interface for the functionality
35 * needed to implement kunit->abort() which in turn is needed for implementing
36 * assertions. Assertions allow stating a precondition for a test simplifying
37 * how test cases are written and presented.
38 *
39 * Assertions are like expectations, except they abort (call
40 * kunit_try_catch_throw()) when the specified condition is not met. This is
41 * useful when you look at a test case as a logical statement about some piece
42 * of code, where assertions are the premises for the test case, and the
43 * conclusion is a set of predicates, rather expectations, that must all be
44 * true. If your premises are violated, it does not makes sense to continue.
45 */
46 struct kunit_try_catch {
47 /* private: internal use only. */
48 struct kunit *test;
49 struct completion *try_completion;
50 int try_result;
51 kunit_try_catch_func_t try;
52 kunit_try_catch_func_t catch;
53 void *context;
54 };
55
56 void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context);
57
58 void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch);
59
kunit_try_catch_get_result(struct kunit_try_catch * try_catch)60 static inline int kunit_try_catch_get_result(struct kunit_try_catch *try_catch)
61 {
62 return try_catch->try_result;
63 }
64
65 #endif /* _KUNIT_TRY_CATCH_H */
66