diff options
Diffstat (limited to 'include/kunit')
| -rw-r--r-- | include/kunit/static_stub.h | 113 | ||||
| -rw-r--r-- | include/kunit/test-bug.h | 29 | ||||
| -rw-r--r-- | include/kunit/test.h | 6 |
3 files changed, 127 insertions, 21 deletions
diff --git a/include/kunit/static_stub.h b/include/kunit/static_stub.h new file mode 100644 index 000000000000..9b80150a5d62 --- /dev/null +++ b/include/kunit/static_stub.h @@ -0,0 +1,113 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * KUnit function redirection (static stubbing) API. + * + * Copyright (C) 2022, Google LLC. + * Author: David Gow <davidgow@google.com> + */ +#ifndef _KUNIT_STATIC_STUB_H +#define _KUNIT_STATIC_STUB_H + +#if !IS_ENABLED(CONFIG_KUNIT) + +/* If CONFIG_KUNIT is not enabled, these stubs quietly disappear. */ +#define KUNIT_TRIGGER_STATIC_STUB(real_fn_name, args...) do {} while (0) + +#else + +#include <kunit/test.h> +#include <kunit/test-bug.h> + +#include <linux/compiler.h> /* for {un,}likely() */ +#include <linux/sched.h> /* for task_struct */ + + +/** + * KUNIT_STATIC_STUB_REDIRECT() - call a replacement 'static stub' if one exists + * @real_fn_name: The name of this function (as an identifier, not a string) + * @args: All of the arguments passed to this function + * + * This is a function prologue which is used to allow calls to the current + * function to be redirected by a KUnit test. KUnit tests can call + * kunit_activate_static_stub() to pass a replacement function in. The + * replacement function will be called by KUNIT_TRIGGER_STATIC_STUB(), which + * will then return from the function. If the caller is not in a KUnit context, + * the function will continue execution as normal. + * + * Example: + * + * .. code-block:: c + * + * int real_func(int n) + * { + * KUNIT_STATIC_STUB_REDIRECT(real_func, n); + * return 0; + * } + * + * int replacement_func(int n) + * { + * return 42; + * } + * + * void example_test(struct kunit *test) + * { + * kunit_activate_static_stub(test, real_func, replacement_func); + * KUNIT_EXPECT_EQ(test, real_func(1), 42); + * } + * + */ +#define KUNIT_STATIC_STUB_REDIRECT(real_fn_name, args...) \ +do { \ + typeof(&real_fn_name) replacement; \ + struct kunit *current_test = kunit_get_current_test(); \ + \ + if (likely(!current_test)) \ + break; \ + \ + replacement = kunit_hooks.get_static_stub_address(current_test, \ + &real_fn_name); \ + \ + if (unlikely(replacement)) \ + return replacement(args); \ +} while (0) + +/* Helper function for kunit_activate_static_stub(). The macro does + * typechecking, so use it instead. + */ +void __kunit_activate_static_stub(struct kunit *test, + void *real_fn_addr, + void *replacement_addr); + +/** + * kunit_activate_static_stub() - replace a function using static stubs. + * @test: A pointer to the 'struct kunit' test context for the current test. + * @real_fn_addr: The address of the function to replace. + * @replacement_addr: The address of the function to replace it with. + * + * When activated, calls to real_fn_addr from within this test (even if called + * indirectly) will instead call replacement_addr. The function pointed to by + * real_fn_addr must begin with the static stub prologue in + * KUNIT_TRIGGER_STATIC_STUB() for this to work. real_fn_addr and + * replacement_addr must have the same type. + * + * The redirection can be disabled again with kunit_deactivate_static_stub(). + */ +#define kunit_activate_static_stub(test, real_fn_addr, replacement_addr) do { \ + typecheck_fn(typeof(&real_fn_addr), replacement_addr); \ + __kunit_activate_static_stub(test, real_fn_addr, replacement_addr); \ +} while (0) + + +/** + * kunit_deactivate_static_stub() - disable a function redirection + * @test: A pointer to the 'struct kunit' test context for the current test. + * @real_fn_addr: The address of the function to no-longer redirect + * + * Deactivates a redirection configured with kunit_activate_static_stub(). After + * this function returns, calls to real_fn_addr() will execute the original + * real_fn, not any previously-configured replacement. + */ +void kunit_deactivate_static_stub(struct kunit *test, void *real_fn_addr); + +#endif +#endif diff --git a/include/kunit/test-bug.h b/include/kunit/test-bug.h index c1b2e14eab64..30ca541b6ff2 100644 --- a/include/kunit/test-bug.h +++ b/include/kunit/test-bug.h @@ -1,6 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ /* - * KUnit API allowing dynamic analysis tools to interact with KUnit tests + * KUnit API providing hooks for non-test code to interact with tests. * * Copyright (C) 2020, Google LLC. * Author: Uriel Guajardo <urielguajardo@google.com> @@ -9,7 +9,7 @@ #ifndef _KUNIT_TEST_BUG_H #define _KUNIT_TEST_BUG_H -#if IS_BUILTIN(CONFIG_KUNIT) +#if IS_ENABLED(CONFIG_KUNIT) #include <linux/jump_label.h> /* For static branch */ #include <linux/sched.h> @@ -17,6 +17,12 @@ /* Static key if KUnit is running any tests. */ DECLARE_STATIC_KEY_FALSE(kunit_running); +/* Hooks table: a table of function pointers filled in when kunit loads */ +extern struct kunit_hooks_table { + __printf(3, 4) void (*fail_current_test)(const char*, int, const char*, ...); + void *(*get_static_stub_address)(struct kunit *test, void *real_fn_addr); +} kunit_hooks; + /** * kunit_get_current_test() - Return a pointer to the currently running * KUnit test. @@ -43,33 +49,20 @@ static inline struct kunit *kunit_get_current_test(void) * kunit_fail_current_test() - If a KUnit test is running, fail it. * * If a KUnit test is running in the current task, mark that test as failed. - * - * This macro will only work if KUnit is built-in (though the tests - * themselves can be modules). Otherwise, it compiles down to nothing. */ #define kunit_fail_current_test(fmt, ...) do { \ if (static_branch_unlikely(&kunit_running)) { \ - __kunit_fail_current_test(__FILE__, __LINE__, \ + /* Guaranteed to be non-NULL when kunit_running true*/ \ + kunit_hooks.fail_current_test(__FILE__, __LINE__, \ fmt, ##__VA_ARGS__); \ } \ } while (0) - -extern __printf(3, 4) void __kunit_fail_current_test(const char *file, int line, - const char *fmt, ...); - #else static inline struct kunit *kunit_get_current_test(void) { return NULL; } -/* We define this with an empty helper function so format string warnings work */ -#define kunit_fail_current_test(fmt, ...) \ - __kunit_fail_current_test(__FILE__, __LINE__, fmt, ##__VA_ARGS__) - -static inline __printf(3, 4) void __kunit_fail_current_test(const char *file, int line, - const char *fmt, ...) -{ -} +#define kunit_fail_current_test(fmt, ...) do {} while (0) #endif diff --git a/include/kunit/test.h b/include/kunit/test.h index 87ea90576b50..08d3559dd703 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -303,7 +303,6 @@ static inline int kunit_run_all_tests(void) */ #define kunit_test_init_section_suites(__suites...) \ __kunit_test_suites(CONCATENATE(__UNIQUE_ID(array), _probe), \ - CONCATENATE(__UNIQUE_ID(suites), _probe), \ ##__suites) #define kunit_test_init_section_suite(suite) \ @@ -683,8 +682,9 @@ do { \ .right_text = #right, \ }; \ \ - if (likely(memcmp(__left, __right, __size) op 0)) \ - break; \ + if (likely(__left && __right)) \ + if (likely(memcmp(__left, __right, __size) op 0)) \ + break; \ \ _KUNIT_FAILED(test, \ assert_type, \ |