1 /* 2 * Copyright (c) Yann Collet, Facebook, Inc. 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) size_t const e = f; if (ERR_isError(e)) return e 64 #define CHECK_F(f) { CHECK_V_F(_var_err__, f); } 65 66 67 /*-**************************************** 68 * Error Strings 69 ******************************************/ 70 71 const char* ERR_getErrorString(ERR_enum code); /* error_private.c */ 72 73 ERR_STATIC const char* ERR_getErrorName(size_t code) 74 { 75 return ERR_getErrorString(ERR_getErrorCode(code)); 76 } 77 78 /** 79 * Ignore: this is an internal helper. 80 * 81 * This is a helper function to help force C99-correctness during compilation. 82 * Under strict compilation modes, variadic macro arguments can't be empty. 83 * However, variadic function arguments can be. Using a function therefore lets 84 * us statically check that at least one (string) argument was passed, 85 * independent of the compilation flags. 86 */ 87 static INLINE_KEYWORD UNUSED_ATTR 88 void _force_has_format_string(const char *format, ...) { 89 (void)format; 90 } 91 92 /** 93 * Ignore: this is an internal helper. 94 * 95 * We want to force this function invocation to be syntactically correct, but 96 * we don't want to force runtime evaluation of its arguments. 97 */ 98 #define _FORCE_HAS_FORMAT_STRING(...) \ 99 if (0) { \ 100 _force_has_format_string(__VA_ARGS__); \ 101 } 102 103 #define ERR_QUOTE(str) #str 104 105 /** 106 * Return the specified error if the condition evaluates to true. 107 * 108 * In debug modes, prints additional information. 109 * In order to do that (particularly, printing the conditional that failed), 110 * this can't just wrap RETURN_ERROR(). 111 */ 112 #define RETURN_ERROR_IF(cond, err, ...) \ 113 if (cond) { \ 114 RAWLOG(3, "%s:%d: ERROR!: check %s failed, returning %s", \ 115 __FILE__, __LINE__, ERR_QUOTE(cond), ERR_QUOTE(ERROR(err))); \ 116 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \ 117 RAWLOG(3, ": " __VA_ARGS__); \ 118 RAWLOG(3, "\n"); \ 119 return ERROR(err); \ 120 } 121 122 /** 123 * Unconditionally return the specified error. 124 * 125 * In debug modes, prints additional information. 126 */ 127 #define RETURN_ERROR(err, ...) \ 128 do { \ 129 RAWLOG(3, "%s:%d: ERROR!: unconditional check failed, returning %s", \ 130 __FILE__, __LINE__, ERR_QUOTE(ERROR(err))); \ 131 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \ 132 RAWLOG(3, ": " __VA_ARGS__); \ 133 RAWLOG(3, "\n"); \ 134 return ERROR(err); \ 135 } while(0); 136 137 /** 138 * If the provided expression evaluates to an error code, returns that error code. 139 * 140 * In debug modes, prints additional information. 141 */ 142 #define FORWARD_IF_ERROR(err, ...) \ 143 do { \ 144 size_t const err_code = (err); \ 145 if (ERR_isError(err_code)) { \ 146 RAWLOG(3, "%s:%d: ERROR!: forwarding error in %s: %s", \ 147 __FILE__, __LINE__, ERR_QUOTE(err), ERR_getErrorName(err_code)); \ 148 _FORCE_HAS_FORMAT_STRING(__VA_ARGS__); \ 149 RAWLOG(3, ": " __VA_ARGS__); \ 150 RAWLOG(3, "\n"); \ 151 return err_code; \ 152 } \ 153 } while(0); 154 155 #if defined (__cplusplus) 156 } 157 #endif 158 159 #endif /* ERROR_H_MODULE */ 160