1 /* 2 * Copyright (c) Meta Platforms, Inc. and affiliates. 3 * All rights reserved. 4 * 5 * This source code is licensed under both the BSD-style license (found in the 6 * LICENSE file in the root directory of this source tree) and the GPLv2 (found 7 * in the COPYING file in the root directory of this source tree). 8 * You may select, at your option, one of the above-listed licenses. 9 */ 10 11 /* Note : this module is expected to remain private, do not expose it */ 12 13 #ifndef ERROR_H_MODULE 14 #define ERROR_H_MODULE 15 16 #if defined (__cplusplus) 17 extern "C" { 18 #endif 19 20 21 /* **************************************** 22 * Dependencies 23 ******************************************/ 24 #include "../zstd_errors.h" /* enum list */ 25 #include "compiler.h" 26 #include "debug.h" 27 #include "zstd_deps.h" /* size_t */ 28 29 30 /* **************************************** 31 * Compiler-specific 32 ******************************************/ 33 #if defined(__GNUC__) 34 # define ERR_STATIC static __attribute__((unused)) 35 #elif defined (__cplusplus) || (defined (__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L) /* C99 */) 36 # define ERR_STATIC static inline 37 #elif defined(_MSC_VER) 38 # define ERR_STATIC static __inline 39 #else 40 # define ERR_STATIC static /* this version may generate warnings for unused static functions; disable the relevant warning */ 41 #endif 42 43 44 /*-**************************************** 45 * Customization (error_public.h) 46 ******************************************/ 47 typedef ZSTD_ErrorCode ERR_enum; 48 #define PREFIX(name) ZSTD_error_##name 49 50 51 /*-**************************************** 52 * Error codes handling 53 ******************************************/ 54 #undef ERROR /* already defined on Visual Studio */ 55 #define ERROR(name) ZSTD_ERROR(name) 56 #define ZSTD_ERROR(name) ((size_t)-PREFIX(name)) 57 58 ERR_STATIC unsigned ERR_isError(size_t code) { return (code > ERROR(maxCode)); } 59 60 ERR_STATIC ERR_enum ERR_getErrorCode(size_t code) { if (!ERR_isError(code)) return (ERR_enum)0; return (ERR_enum) (0-code); } 61 62 /* check and forward error code */ 63 #define CHECK_V_F(e, f) \ 64 size_t const e = f; \ 65 do { \ 66 if (ERR_isError(e)) \ 67 return e; \ 68 } while (0) 69 #define CHECK_F(f) do { CHECK_V_F(_var_err__, f); } while (0) 70 71 72 /*-**************************************** 73 * Error Strings 74 ******************************************/ 75 76 const char* ERR_getErrorString(ERR_enum code); /* error_private.c */ 77 78 ERR_STATIC const char* ERR_getErrorName(size_t code) 79 { 80 return ERR_getErrorString(ERR_getErrorCode(code)); 81 } 82 83 /** 84 * Ignore: this is an internal helper. 85 * 86 * This is a helper function to help force C99-correctness during compilation. 87 * Under strict compilation modes, variadic macro arguments can't be empty. 88 * However, variadic function arguments can be. Using a function therefore lets 89 * us statically check that at least one (string) argument was passed, 90 * independent of the compilation flags. 91 */ 92 static INLINE_KEYWORD UNUSED_ATTR 93 void _force_has_format_string(const char *format, ...) { 94 (void)format; 95 } 96 97 /** 98 * Ignore: this is an internal helper. 99 * 100 * We want to force this function invocation to be syntactically correct, but 101 * we don't want to force runtime evaluation of its arguments. 102 */ 103 #define _FORCE_HAS_FORMAT_STRING(...) \ 104 do { \ 105 if (0) { \ 106 _force_has_format_string(__VA_ARGS__); \ 107 } \ 108 } while (0) 109 110 #define ERR_QUOTE(str) #str 111 112 /** 113 * Return the specified error if the condition evaluates to true. 114 * 115 * In debug modes, prints additional information. 116 * In order to do that (particularly, printing the conditional that failed), 117 * this can't just wrap RETURN_ERROR(). 118 */ 119 #define RETURN_ERROR_IF(cond, err, ...) \ 120 do { \ 121 if (cond) { \ 122 RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \ 123 __FILE__, __LINE__, ERR_QUOTE(cond), ERR_QUOTE(ERROR(err))); \ 124 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \ 125 RAWLOG(3, ": " __VA_ARGS__); \ 126 RAWLOG(3, "\n"); \ 127 return ERROR(err); \ 128 } \ 129 } while (0) 130 131 /** 132 * Unconditionally return the specified error. 133 * 134 * In debug modes, prints additional information. 135 */ 136 #define RETURN_ERROR(err, ...) \ 137 do { \ 138 RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \ 139 __FILE__, __LINE__, ERR_QUOTE(ERROR(err))); \ 140 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \ 141 RAWLOG(3, ": " __VA_ARGS__); \ 142 RAWLOG(3, "\n"); \ 143 return ERROR(err); \ 144 } while(0) 145 146 /** 147 * If the provided expression evaluates to an error code, returns that error code. 148 * 149 * In debug modes, prints additional information. 150 */ 151 #define FORWARD_IF_ERROR(err, ...) \ 152 do { \ 153 size_t const err_code = (err); \ 154 if (ERR_isError(err_code)) { \ 155 RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \ 156 __FILE__, __LINE__, ERR_QUOTE(err), ERR_getErrorName(err_code)); \ 157 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \ 158 RAWLOG(3, ": " __VA_ARGS__); \ 159 RAWLOG(3, "\n"); \ 160 return err_code; \ 161 } \ 162 } while(0) 163 164 #if defined (__cplusplus) 165 } 166 #endif 167 168 #endif /* ERROR_H_MODULE */ 169