| 1 | /* ANSI and traditional C compatability macros |
| 2 | Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001 |
| 3 | Free Software Foundation, Inc. |
| 4 | This file is part of the GNU C Library. |
| 5 | |
| 6 | This program is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2 of the License, or |
| 9 | (at your option) any later version. |
| 10 | |
| 11 | This program is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with this program; if not, write to the Free Software |
| 18 | Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ |
| 19 | |
| 20 | /* ANSI and traditional C compatibility macros |
| 21 | |
| 22 | ANSI C is assumed if __STDC__ is #defined. |
| 23 | |
| 24 | Macro ANSI C definition Traditional C definition |
| 25 | ----- ---- - ---------- ----------- - ---------- |
| 26 | ANSI_PROTOTYPES 1 not defined |
| 27 | PTR `void *' `char *' |
| 28 | PTRCONST `void *const' `char *' |
| 29 | LONG_DOUBLE `long double' `double' |
| 30 | const not defined `' |
| 31 | volatile not defined `' |
| 32 | signed not defined `' |
| 33 | VA_START(ap, var) va_start(ap, var) va_start(ap) |
| 34 | |
| 35 | Note that it is safe to write "void foo();" indicating a function |
| 36 | with no return value, in all K+R compilers we have been able to test. |
| 37 | |
| 38 | For declaring functions with prototypes, we also provide these: |
| 39 | |
| 40 | PARAMS ((prototype)) |
| 41 | -- for functions which take a fixed number of arguments. Use this |
| 42 | when declaring the function. When defining the function, write a |
| 43 | K+R style argument list. For example: |
| 44 | |
| 45 | char *strcpy PARAMS ((char *dest, char *source)); |
| 46 | ... |
| 47 | char * |
| 48 | strcpy (dest, source) |
| 49 | char *dest; |
| 50 | char *source; |
| 51 | { ... } |
| 52 | |
| 53 | |
| 54 | VPARAMS ((prototype, ...)) |
| 55 | -- for functions which take a variable number of arguments. Use |
| 56 | PARAMS to declare the function, VPARAMS to define it. For example: |
| 57 | |
| 58 | int printf PARAMS ((const char *format, ...)); |
| 59 | ... |
| 60 | int |
| 61 | printf VPARAMS ((const char *format, ...)) |
| 62 | { |
| 63 | ... |
| 64 | } |
| 65 | |
| 66 | For writing functions which take variable numbers of arguments, we |
| 67 | also provide the VA_OPEN, VA_CLOSE, and VA_FIXEDARG macros. These |
| 68 | hide the differences between K+R <varargs.h> and C89 <stdarg.h> more |
| 69 | thoroughly than the simple VA_START() macro mentioned above. |
| 70 | |
| 71 | VA_OPEN and VA_CLOSE are used *instead of* va_start and va_end. |
| 72 | Immediately after VA_OPEN, put a sequence of VA_FIXEDARG calls |
| 73 | corresponding to the list of fixed arguments. Then use va_arg |
| 74 | normally to get the variable arguments, or pass your va_list object |
| 75 | around. You do not declare the va_list yourself; VA_OPEN does it |
| 76 | for you. |
| 77 | |
| 78 | Here is a complete example: |
| 79 | |
| 80 | int |
| 81 | printf VPARAMS ((const char *format, ...)) |
| 82 | { |
| 83 | int result; |
| 84 | |
| 85 | VA_OPEN (ap, format); |
| 86 | VA_FIXEDARG (ap, const char *, format); |
| 87 | |
| 88 | result = vfprintf (stdout, format, ap); |
| 89 | VA_CLOSE (ap); |
| 90 | |
| 91 | return result; |
| 92 | } |
| 93 | |
| 94 | |
| 95 | You can declare variables either before or after the VA_OPEN, |
| 96 | VA_FIXEDARG sequence. Also, VA_OPEN and VA_CLOSE are the beginning |
| 97 | and end of a block. They must appear at the same nesting level, |
| 98 | and any variables declared after VA_OPEN go out of scope at |
| 99 | VA_CLOSE. Unfortunately, with a K+R compiler, that includes the |
| 100 | argument list. You can have multiple instances of VA_OPEN/VA_CLOSE |
| 101 | pairs in a single function in case you need to traverse the |
| 102 | argument list more than once. |
| 103 | |
| 104 | For ease of writing code which uses GCC extensions but needs to be |
| 105 | portable to other compilers, we provide the GCC_VERSION macro that |
| 106 | simplifies testing __GNUC__ and __GNUC_MINOR__ together, and various |
| 107 | wrappers around __attribute__. Also, __extension__ will be #defined |
| 108 | to nothing if it doesn't work. See below. |
| 109 | |
| 110 | This header also defines a lot of obsolete macros: |
| 111 | CONST, VOLATILE, SIGNED, PROTO, EXFUN, DEFUN, DEFUN_VOID, |
| 112 | AND, DOTS, NOARGS. Don't use them. */ |
| 113 | |
| 114 | #ifndef _ANSIDECL_H |
| 115 | #define _ANSIDECL_H 1 |
| 116 | |
| 117 | /* Every source file includes this file, |
| 118 | so they will all get the switch for lint. */ |
| 119 | /* LINTLIBRARY */ |
| 120 | |
| 121 | /* Using MACRO(x,y) in cpp #if conditionals does not work with some |
| 122 | older preprocessors. Thus we can't define something like this: |
| 123 | |
| 124 | #define HAVE_GCC_VERSION(MAJOR, MINOR) \ |
| 125 | (__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR))) |
| 126 | |
| 127 | and then test "#if HAVE_GCC_VERSION(2,7)". |
| 128 | |
| 129 | So instead we use the macro below and test it against specific values. */ |
| 130 | |
| 131 | /* This macro simplifies testing whether we are using gcc, and if it |
| 132 | is of a particular minimum version. (Both major & minor numbers are |
| 133 | significant.) This macro will evaluate to 0 if we are not using |
| 134 | gcc at all. */ |
| 135 | #ifndef GCC_VERSION |
| 136 | #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) |
| 137 | #endif /* GCC_VERSION */ |
| 138 | |
| 139 | #if defined (__STDC__) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(_WIN32) || (defined(__alpha) && defined(__cplusplus)) |
| 140 | /* All known AIX compilers implement these things (but don't always |
| 141 | define __STDC__). The RISC/OS MIPS compiler defines these things |
| 142 | in SVR4 mode, but does not define __STDC__. */ |
| 143 | /* eraxxon@alumni.rice.edu: The Compaq C++ compiler, unlike many other |
| 144 | C++ compilers, does not define __STDC__, though it acts as if this |
| 145 | was so. (Verified versions: 5.7, 6.2, 6.3, 6.5) */ |
| 146 | |
| 147 | #define ANSI_PROTOTYPES 1 |
| 148 | #define PTR void * |
| 149 | #define PTRCONST void *const |
| 150 | #define LONG_DOUBLE long double |
| 151 | |
| 152 | #define PARAMS(ARGS) ARGS |
| 153 | #define VPARAMS(ARGS) ARGS |
| 154 | #define VA_START(VA_LIST, VAR) va_start(VA_LIST, VAR) |
| 155 | |
| 156 | /* variadic function helper macros */ |
| 157 | /* "struct Qdmy" swallows the semicolon after VA_OPEN/VA_FIXEDARG's |
| 158 | use without inhibiting further decls and without declaring an |
| 159 | actual variable. */ |
| 160 | #define VA_OPEN(AP, VAR) { va_list AP; va_start(AP, VAR); { struct Qdmy |
| 161 | #define VA_CLOSE(AP) } va_end(AP); } |
| 162 | #define VA_FIXEDARG(AP, T, N) struct Qdmy |
| 163 | |
| 164 | #undef const |
| 165 | #undef volatile |
| 166 | #undef signed |
| 167 | |
| 168 | /* inline requires special treatment; it's in C99, and GCC >=2.7 supports |
| 169 | it too, but it's not in C89. */ |
| 170 | #undef inline |
| 171 | #if __STDC_VERSION__ > 199901L |
| 172 | /* it's a keyword */ |
| 173 | #else |
| 174 | # if GCC_VERSION >= 2007 |
| 175 | # define inline __inline__ /* __inline__ prevents -pedantic warnings */ |
| 176 | # else |
| 177 | # define inline /* nothing */ |
| 178 | # endif |
| 179 | #endif |
| 180 | |
| 181 | /* These are obsolete. Do not use. */ |
| 182 | #ifndef IN_GCC |
| 183 | #define CONST const |
| 184 | #define VOLATILE volatile |
| 185 | #define SIGNED signed |
| 186 | |
| 187 | #define PROTO(type, name, arglist) type name arglist |
| 188 | #define EXFUN(name, proto) name proto |
| 189 | #define DEFUN(name, arglist, args) name(args) |
| 190 | #define DEFUN_VOID(name) name(void) |
| 191 | #define AND , |
| 192 | #define DOTS , ... |
| 193 | #define NOARGS void |
| 194 | #endif /* ! IN_GCC */ |
| 195 | |
| 196 | #else /* Not ANSI C. */ |
| 197 | |
| 198 | #undef ANSI_PROTOTYPES |
| 199 | #define PTR char * |
| 200 | #define PTRCONST PTR |
| 201 | #define LONG_DOUBLE double |
| 202 | |
| 203 | #define PARAMS(args) () |
| 204 | #define VPARAMS(args) (va_alist) va_dcl |
| 205 | #define VA_START(va_list, var) va_start(va_list) |
| 206 | |
| 207 | #define VA_OPEN(AP, VAR) { va_list AP; va_start(AP); { struct Qdmy |
| 208 | #define VA_CLOSE(AP) } va_end(AP); } |
| 209 | #define VA_FIXEDARG(AP, TYPE, NAME) TYPE NAME = va_arg(AP, TYPE) |
| 210 | |
| 211 | /* some systems define these in header files for non-ansi mode */ |
| 212 | #undef const |
| 213 | #undef volatile |
| 214 | #undef signed |
| 215 | #undef inline |
| 216 | #define const |
| 217 | #define volatile |
| 218 | #define signed |
| 219 | #define inline |
| 220 | |
| 221 | #ifndef IN_GCC |
| 222 | #define CONST |
| 223 | #define VOLATILE |
| 224 | #define SIGNED |
| 225 | |
| 226 | #define PROTO(type, name, arglist) type name () |
| 227 | #define EXFUN(name, proto) name() |
| 228 | #define DEFUN(name, arglist, args) name arglist args; |
| 229 | #define DEFUN_VOID(name) name() |
| 230 | #define AND ; |
| 231 | #define DOTS |
| 232 | #define NOARGS |
| 233 | #endif /* ! IN_GCC */ |
| 234 | |
| 235 | #endif /* ANSI C. */ |
| 236 | |
| 237 | /* Define macros for some gcc attributes. This permits us to use the |
| 238 | macros freely, and know that they will come into play for the |
| 239 | version of gcc in which they are supported. */ |
| 240 | |
| 241 | #if (GCC_VERSION < 2007) |
| 242 | # define __attribute__(x) |
| 243 | #endif |
| 244 | |
| 245 | /* Attribute __malloc__ on functions was valid as of gcc 2.96. */ |
| 246 | #ifndef ATTRIBUTE_MALLOC |
| 247 | # if (GCC_VERSION >= 2096) |
| 248 | # define ATTRIBUTE_MALLOC __attribute__ ((__malloc__)) |
| 249 | # else |
| 250 | # define ATTRIBUTE_MALLOC |
| 251 | # endif /* GNUC >= 2.96 */ |
| 252 | #endif /* ATTRIBUTE_MALLOC */ |
| 253 | |
| 254 | /* Attributes on labels were valid as of gcc 2.93. */ |
| 255 | #ifndef ATTRIBUTE_UNUSED_LABEL |
| 256 | # if (GCC_VERSION >= 2093) |
| 257 | # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED |
| 258 | # else |
| 259 | # define ATTRIBUTE_UNUSED_LABEL |
| 260 | # endif /* GNUC >= 2.93 */ |
| 261 | #endif /* ATTRIBUTE_UNUSED_LABEL */ |
| 262 | |
| 263 | #ifndef ATTRIBUTE_UNUSED |
| 264 | #define ATTRIBUTE_UNUSED __attribute__ ((__unused__)) |
| 265 | #endif /* ATTRIBUTE_UNUSED */ |
| 266 | |
| 267 | #ifndef ATTRIBUTE_NORETURN |
| 268 | #define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__)) |
| 269 | #endif /* ATTRIBUTE_NORETURN */ |
| 270 | |
| 271 | /* Attribute `nonnull' was valid as of gcc 3.3. */ |
| 272 | #ifndef ATTRIBUTE_NONNULL |
| 273 | # if (GCC_VERSION >= 3003) |
| 274 | # define ATTRIBUTE_NONNULL(m) __attribute__ ((__nonnull__ (m))) |
| 275 | # else |
| 276 | # define ATTRIBUTE_NONNULL(m) |
| 277 | # endif /* GNUC >= 3.3 */ |
| 278 | #endif /* ATTRIBUTE_NONNULL */ |
| 279 | |
| 280 | /* Use ATTRIBUTE_PRINTF when the format specifier must not be NULL. |
| 281 | This was the case for the `printf' format attribute by itself |
| 282 | before GCC 3.3, but as of 3.3 we need to add the `nonnull' |
| 283 | attribute to retain this behavior. */ |
| 284 | #ifndef ATTRIBUTE_PRINTF |
| 285 | #define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) ATTRIBUTE_NONNULL(m) |
| 286 | #define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2) |
| 287 | #define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3) |
| 288 | #define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4) |
| 289 | #define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5) |
| 290 | #define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6) |
| 291 | #endif /* ATTRIBUTE_PRINTF */ |
| 292 | |
| 293 | /* Use ATTRIBUTE_NULL_PRINTF when the format specifier may be NULL. A |
| 294 | NULL format specifier was allowed as of gcc 3.3. */ |
| 295 | #ifndef ATTRIBUTE_NULL_PRINTF |
| 296 | # if (GCC_VERSION >= 3003) |
| 297 | # define ATTRIBUTE_NULL_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) |
| 298 | # else |
| 299 | # define ATTRIBUTE_NULL_PRINTF(m, n) |
| 300 | # endif /* GNUC >= 3.3 */ |
| 301 | # define ATTRIBUTE_NULL_PRINTF_1 ATTRIBUTE_NULL_PRINTF(1, 2) |
| 302 | # define ATTRIBUTE_NULL_PRINTF_2 ATTRIBUTE_NULL_PRINTF(2, 3) |
| 303 | # define ATTRIBUTE_NULL_PRINTF_3 ATTRIBUTE_NULL_PRINTF(3, 4) |
| 304 | # define ATTRIBUTE_NULL_PRINTF_4 ATTRIBUTE_NULL_PRINTF(4, 5) |
| 305 | # define ATTRIBUTE_NULL_PRINTF_5 ATTRIBUTE_NULL_PRINTF(5, 6) |
| 306 | #endif /* ATTRIBUTE_NULL_PRINTF */ |
| 307 | |
| 308 | /* We use __extension__ in some places to suppress -pedantic warnings |
| 309 | about GCC extensions. This feature didn't work properly before |
| 310 | gcc 2.8. */ |
| 311 | #if GCC_VERSION < 2008 |
| 312 | #define __extension__ |
| 313 | #endif |
| 314 | |
| 315 | #endif /* ansidecl.h */ |