xref: /linux/include/kunit/try-catch.h (revision 300a90b2cb5d442879e6398920c49aebbd5c8e40)
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 kunit;
18 
19 /**
20  * struct kunit_try_catch - provides a generic way to run code which might fail.
21  * @test: The test case that is currently being executed.
22  * @try_result: Contains any errno obtained while running test case.
23  * @try: The function, the test case, to attempt to run.
24  * @catch: The function called if @try bails out.
25  * @context: used to pass user data to the try and catch functions.
26  *
27  * kunit_try_catch provides a generic, architecture independent way to execute
28  * an arbitrary function of type kunit_try_catch_func_t which may bail out by
29  * calling kunit_try_catch_throw(). If kunit_try_catch_throw() is called, @try
30  * is stopped at the site of invocation and @catch is called.
31  *
32  * struct kunit_try_catch provides a generic interface for the functionality
33  * needed to implement kunit->abort() which in turn is needed for implementing
34  * assertions. Assertions allow stating a precondition for a test simplifying
35  * how test cases are written and presented.
36  *
37  * Assertions are like expectations, except they abort (call
38  * kunit_try_catch_throw()) when the specified condition is not met. This is
39  * useful when you look at a test case as a logical statement about some piece
40  * of code, where assertions are the premises for the test case, and the
41  * conclusion is a set of predicates, rather expectations, that must all be
42  * true. If your premises are violated, it does not makes sense to continue.
43  */
44 struct kunit_try_catch {
45 	/* private: internal use only. */
46 	struct kunit *test;
47 	int try_result;
48 	kunit_try_catch_func_t try;
49 	kunit_try_catch_func_t catch;
50 	void *context;
51 };
52 
53 void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context);
54 
55 void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch);
56 
57 static inline int kunit_try_catch_get_result(struct kunit_try_catch *try_catch)
58 {
59 	return try_catch->try_result;
60 }
61 
62 #endif /* _KUNIT_TRY_CATCH_H */
63