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_init(struct kunit_try_catch *try_catch, 57 struct kunit *test, 58 kunit_try_catch_func_t try, 59 kunit_try_catch_func_t catch); 60 61 void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context); 62 63 void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch); 64 65 static inline int kunit_try_catch_get_result(struct kunit_try_catch *try_catch) 66 { 67 return try_catch->try_result; 68 } 69 70 /* 71 * Exposed for testing only. 72 */ 73 void kunit_generic_try_catch_init(struct kunit_try_catch *try_catch); 74 75 #endif /* _KUNIT_TRY_CATCH_H */ 76