1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright 2023 Red Hat 4 */ 5 6 #ifndef PERMASSERT_H 7 #define PERMASSERT_H 8 9 #include <linux/compiler.h> 10 11 #include "errors.h" 12 13 /* Utilities for asserting that certain conditions are met */ 14 15 #define STRINGIFY(X) #X 16 17 /* 18 * A hack to apply the "warn if unused" attribute to an integral expression. 19 * 20 * Since GCC doesn't propagate the warn_unused_result attribute to conditional expressions 21 * incorporating calls to functions with that attribute, this function can be used to wrap such an 22 * expression. With optimization enabled, this function contributes no additional instructions, but 23 * the warn_unused_result attribute still applies to the code calling it. 24 */ 25 static inline int __must_check vdo_must_use(int value) 26 { 27 return value; 28 } 29 30 /* Assert that an expression is true and return an error if it is not. */ 31 #define VDO_ASSERT(expr, ...) vdo_must_use(__VDO_ASSERT(expr, __VA_ARGS__)) 32 33 /* Log a message if the expression is not true. */ 34 #define VDO_ASSERT_LOG_ONLY(expr, ...) __VDO_ASSERT(expr, __VA_ARGS__) 35 36 #define __VDO_ASSERT(expr, ...) \ 37 (likely(expr) ? VDO_SUCCESS \ 38 : vdo_assertion_failed(STRINGIFY(expr), __FILE__, __LINE__, __VA_ARGS__)) 39 40 /* Log an assertion failure message. */ 41 int vdo_assertion_failed(const char *expression_string, const char *file_name, 42 int line_number, const char *format, ...) 43 __printf(4, 5); 44 45 #endif /* PERMASSERT_H */ 46