| 1 | /* ANSI and traditional C compatability macros |
| 2 | Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001, |
| 3 | 2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010 |
| 4 | Free Software Foundation, Inc. |
| 5 | This file is part of the GNU C Library. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ |
| 20 | |
| 21 | /* ANSI and traditional C compatibility macros |
| 22 | |
| 23 | ANSI C is assumed if __STDC__ is #defined. |
| 24 | |
| 25 | Macro ANSI C definition Traditional C definition |
| 26 | ----- ---- - ---------- ----------- - ---------- |
| 27 | ANSI_PROTOTYPES 1 not defined |
| 28 | PTR `void *' `char *' |
| 29 | PTRCONST `void *const' `char *' |
| 30 | LONG_DOUBLE `long double' `double' |
| 31 | const not defined `' |
| 32 | volatile not defined `' |
| 33 | signed not defined `' |
| 34 | VA_START(ap, var) va_start(ap, var) va_start(ap) |
| 35 | |
| 36 | Note that it is safe to write "void foo();" indicating a function |
| 37 | with no return value, in all K+R compilers we have been able to test. |
| 38 | |
| 39 | For declaring functions with prototypes, we also provide these: |
| 40 | |
| 41 | PARAMS ((prototype)) |
| 42 | -- for functions which take a fixed number of arguments. Use this |
| 43 | when declaring the function. When defining the function, write a |
| 44 | K+R style argument list. For example: |
| 45 | |
| 46 | char *strcpy PARAMS ((char *dest, char *source)); |
| 47 | ... |
| 48 | char * |
| 49 | strcpy (dest, source) |
| 50 | char *dest; |
| 51 | char *source; |
| 52 | { ... } |
| 53 | |
| 54 | |
| 55 | VPARAMS ((prototype, ...)) |
| 56 | -- for functions which take a variable number of arguments. Use |
| 57 | PARAMS to declare the function, VPARAMS to define it. For example: |
| 58 | |
| 59 | int printf PARAMS ((const char *format, ...)); |
| 60 | ... |
| 61 | int |
| 62 | printf VPARAMS ((const char *format, ...)) |
| 63 | { |
| 64 | ... |
| 65 | } |
| 66 | |
| 67 | For writing functions which take variable numbers of arguments, we |
| 68 | also provide the VA_OPEN, VA_CLOSE, and VA_FIXEDARG macros. These |
| 69 | hide the differences between K+R <varargs.h> and C89 <stdarg.h> more |
| 70 | thoroughly than the simple VA_START() macro mentioned above. |
| 71 | |
| 72 | VA_OPEN and VA_CLOSE are used *instead of* va_start and va_end. |
| 73 | Immediately after VA_OPEN, put a sequence of VA_FIXEDARG calls |
| 74 | corresponding to the list of fixed arguments. Then use va_arg |
| 75 | normally to get the variable arguments, or pass your va_list object |
| 76 | around. You do not declare the va_list yourself; VA_OPEN does it |
| 77 | for you. |
| 78 | |
| 79 | Here is a complete example: |
| 80 | |
| 81 | int |
| 82 | printf VPARAMS ((const char *format, ...)) |
| 83 | { |
| 84 | int result; |
| 85 | |
| 86 | VA_OPEN (ap, format); |
| 87 | VA_FIXEDARG (ap, const char *, format); |
| 88 | |
| 89 | result = vfprintf (stdout, format, ap); |
| 90 | VA_CLOSE (ap); |
| 91 | |
| 92 | return result; |
| 93 | } |
| 94 | |
| 95 | |
| 96 | You can declare variables either before or after the VA_OPEN, |
| 97 | VA_FIXEDARG sequence. Also, VA_OPEN and VA_CLOSE are the beginning |
| 98 | and end of a block. They must appear at the same nesting level, |
| 99 | and any variables declared after VA_OPEN go out of scope at |
| 100 | VA_CLOSE. Unfortunately, with a K+R compiler, that includes the |
| 101 | argument list. You can have multiple instances of VA_OPEN/VA_CLOSE |
| 102 | pairs in a single function in case you need to traverse the |
| 103 | argument list more than once. |
| 104 | |
| 105 | For ease of writing code which uses GCC extensions but needs to be |
| 106 | portable to other compilers, we provide the GCC_VERSION macro that |
| 107 | simplifies testing __GNUC__ and __GNUC_MINOR__ together, and various |
| 108 | wrappers around __attribute__. Also, __extension__ will be #defined |
| 109 | to nothing if it doesn't work. See below. |
| 110 | |
| 111 | This header also defines a lot of obsolete macros: |
| 112 | CONST, VOLATILE, SIGNED, PROTO, EXFUN, DEFUN, DEFUN_VOID, |
| 113 | AND, DOTS, NOARGS. Don't use them. */ |
| 114 | |
| 115 | #ifndef _ANSIDECL_H |
| 116 | #define _ANSIDECL_H 1 |
| 117 | |
| 118 | #ifdef __cplusplus |
| 119 | extern "C" { |
| 120 | #endif |
| 121 | |
| 122 | /* Every source file includes this file, |
| 123 | so they will all get the switch for lint. */ |
| 124 | /* LINTLIBRARY */ |
| 125 | |
| 126 | /* Using MACRO(x,y) in cpp #if conditionals does not work with some |
| 127 | older preprocessors. Thus we can't define something like this: |
| 128 | |
| 129 | #define HAVE_GCC_VERSION(MAJOR, MINOR) \ |
| 130 | (__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR))) |
| 131 | |
| 132 | and then test "#if HAVE_GCC_VERSION(2,7)". |
| 133 | |
| 134 | So instead we use the macro below and test it against specific values. */ |
| 135 | |
| 136 | /* This macro simplifies testing whether we are using gcc, and if it |
| 137 | is of a particular minimum version. (Both major & minor numbers are |
| 138 | significant.) This macro will evaluate to 0 if we are not using |
| 139 | gcc at all. */ |
| 140 | #ifndef GCC_VERSION |
| 141 | #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) |
| 142 | #endif /* GCC_VERSION */ |
| 143 | |
| 144 | #if defined (__STDC__) || defined(__cplusplus) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(_WIN32) |
| 145 | /* All known AIX compilers implement these things (but don't always |
| 146 | define __STDC__). The RISC/OS MIPS compiler defines these things |
| 147 | in SVR4 mode, but does not define __STDC__. */ |
| 148 | /* eraxxon@alumni.rice.edu: The Compaq C++ compiler, unlike many other |
| 149 | C++ compilers, does not define __STDC__, though it acts as if this |
| 150 | was so. (Verified versions: 5.7, 6.2, 6.3, 6.5) */ |
| 151 | |
| 152 | #define ANSI_PROTOTYPES 1 |
| 153 | #define PTR void * |
| 154 | #define PTRCONST void *const |
| 155 | #define LONG_DOUBLE long double |
| 156 | |
| 157 | /* PARAMS is often defined elsewhere (e.g. by libintl.h), so wrap it in |
| 158 | a #ifndef. */ |
| 159 | #ifndef PARAMS |
| 160 | #define PARAMS(ARGS) ARGS |
| 161 | #endif |
| 162 | |
| 163 | #define VPARAMS(ARGS) ARGS |
| 164 | #define VA_START(VA_LIST, VAR) va_start(VA_LIST, VAR) |
| 165 | |
| 166 | /* variadic function helper macros */ |
| 167 | /* "struct Qdmy" swallows the semicolon after VA_OPEN/VA_FIXEDARG's |
| 168 | use without inhibiting further decls and without declaring an |
| 169 | actual variable. */ |
| 170 | #define VA_OPEN(AP, VAR) { va_list AP; va_start(AP, VAR); { struct Qdmy |
| 171 | #define VA_CLOSE(AP) } va_end(AP); } |
| 172 | #define VA_FIXEDARG(AP, T, N) struct Qdmy |
| 173 | |
| 174 | #undef const |
| 175 | #undef volatile |
| 176 | #undef signed |
| 177 | |
| 178 | /* inline requires special treatment; it's in C99, and GCC >=2.7 supports |
| 179 | it too, but it's not in C89. */ |
| 180 | #undef inline |
| 181 | #if __STDC_VERSION__ >= 199901L || defined(__cplusplus) || (defined(__SUNPRO_C) && defined(__C99FEATURES__)) |
| 182 | /* it's a keyword */ |
| 183 | #else |
| 184 | # if GCC_VERSION >= 2007 |
| 185 | # define inline __inline__ /* __inline__ prevents -pedantic warnings */ |
| 186 | # else |
| 187 | # define inline /* nothing */ |
| 188 | # endif |
| 189 | #endif |
| 190 | |
| 191 | /* These are obsolete. Do not use. */ |
| 192 | #ifndef IN_GCC |
| 193 | #define CONST const |
| 194 | #define VOLATILE volatile |
| 195 | #define SIGNED signed |
| 196 | |
| 197 | #define PROTO(type, name, arglist) type name arglist |
| 198 | #define EXFUN(name, proto) name proto |
| 199 | #define DEFUN(name, arglist, args) name(args) |
| 200 | #define DEFUN_VOID(name) name(void) |
| 201 | #define AND , |
| 202 | #define DOTS , ... |
| 203 | #define NOARGS void |
| 204 | #endif /* ! IN_GCC */ |
| 205 | |
| 206 | #else /* Not ANSI C. */ |
| 207 | |
| 208 | #undef ANSI_PROTOTYPES |
| 209 | #define PTR char * |
| 210 | #define PTRCONST PTR |
| 211 | #define LONG_DOUBLE double |
| 212 | |
| 213 | #define PARAMS(args) () |
| 214 | #define VPARAMS(args) (va_alist) va_dcl |
| 215 | #define VA_START(va_list, var) va_start(va_list) |
| 216 | |
| 217 | #define VA_OPEN(AP, VAR) { va_list AP; va_start(AP); { struct Qdmy |
| 218 | #define VA_CLOSE(AP) } va_end(AP); } |
| 219 | #define VA_FIXEDARG(AP, TYPE, NAME) TYPE NAME = va_arg(AP, TYPE) |
| 220 | |
| 221 | /* some systems define these in header files for non-ansi mode */ |
| 222 | #undef const |
| 223 | #undef volatile |
| 224 | #undef signed |
| 225 | #undef inline |
| 226 | #define const |
| 227 | #define volatile |
| 228 | #define signed |
| 229 | #define inline |
| 230 | |
| 231 | #ifndef IN_GCC |
| 232 | #define CONST |
| 233 | #define VOLATILE |
| 234 | #define SIGNED |
| 235 | |
| 236 | #define PROTO(type, name, arglist) type name () |
| 237 | #define EXFUN(name, proto) name() |
| 238 | #define DEFUN(name, arglist, args) name arglist args; |
| 239 | #define DEFUN_VOID(name) name() |
| 240 | #define AND ; |
| 241 | #define DOTS |
| 242 | #define NOARGS |
| 243 | #endif /* ! IN_GCC */ |
| 244 | |
| 245 | #endif /* ANSI C. */ |
| 246 | |
| 247 | /* Define macros for some gcc attributes. This permits us to use the |
| 248 | macros freely, and know that they will come into play for the |
| 249 | version of gcc in which they are supported. */ |
| 250 | |
| 251 | #if (GCC_VERSION < 2007) |
| 252 | # define __attribute__(x) |
| 253 | #endif |
| 254 | |
| 255 | /* Attribute __malloc__ on functions was valid as of gcc 2.96. */ |
| 256 | #ifndef ATTRIBUTE_MALLOC |
| 257 | # if (GCC_VERSION >= 2096) |
| 258 | # define ATTRIBUTE_MALLOC __attribute__ ((__malloc__)) |
| 259 | # else |
| 260 | # define ATTRIBUTE_MALLOC |
| 261 | # endif /* GNUC >= 2.96 */ |
| 262 | #endif /* ATTRIBUTE_MALLOC */ |
| 263 | |
| 264 | /* Attributes on labels were valid as of gcc 2.93 and g++ 4.5. For |
| 265 | g++ an attribute on a label must be followed by a semicolon. */ |
| 266 | #ifndef ATTRIBUTE_UNUSED_LABEL |
| 267 | # ifndef __cplusplus |
| 268 | # if GCC_VERSION >= 2093 |
| 269 | # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED |
| 270 | # else |
| 271 | # define ATTRIBUTE_UNUSED_LABEL |
| 272 | # endif |
| 273 | # else |
| 274 | # if GCC_VERSION >= 4005 |
| 275 | # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED ; |
| 276 | # else |
| 277 | # define ATTRIBUTE_UNUSED_LABEL |
| 278 | # endif |
| 279 | # endif |
| 280 | #endif |
| 281 | |
| 282 | #ifndef ATTRIBUTE_UNUSED |
| 283 | #define ATTRIBUTE_UNUSED __attribute__ ((__unused__)) |
| 284 | #endif /* ATTRIBUTE_UNUSED */ |
| 285 | |
| 286 | /* Before GCC 3.4, the C++ frontend couldn't parse attributes placed after the |
| 287 | identifier name. */ |
| 288 | #if ! defined(__cplusplus) || (GCC_VERSION >= 3004) |
| 289 | # define ARG_UNUSED(NAME) NAME ATTRIBUTE_UNUSED |
| 290 | #else /* !__cplusplus || GNUC >= 3.4 */ |
| 291 | # define ARG_UNUSED(NAME) NAME |
| 292 | #endif /* !__cplusplus || GNUC >= 3.4 */ |
| 293 | |
| 294 | #ifndef ATTRIBUTE_NORETURN |
| 295 | #define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__)) |
| 296 | #endif /* ATTRIBUTE_NORETURN */ |
| 297 | |
| 298 | /* Attribute `nonnull' was valid as of gcc 3.3. */ |
| 299 | #ifndef ATTRIBUTE_NONNULL |
| 300 | # if (GCC_VERSION >= 3003) |
| 301 | # define ATTRIBUTE_NONNULL(m) __attribute__ ((__nonnull__ (m))) |
| 302 | # else |
| 303 | # define ATTRIBUTE_NONNULL(m) |
| 304 | # endif /* GNUC >= 3.3 */ |
| 305 | #endif /* ATTRIBUTE_NONNULL */ |
| 306 | |
| 307 | /* Attribute `pure' was valid as of gcc 3.0. */ |
| 308 | #ifndef ATTRIBUTE_PURE |
| 309 | # if (GCC_VERSION >= 3000) |
| 310 | # define ATTRIBUTE_PURE __attribute__ ((__pure__)) |
| 311 | # else |
| 312 | # define ATTRIBUTE_PURE |
| 313 | # endif /* GNUC >= 3.0 */ |
| 314 | #endif /* ATTRIBUTE_PURE */ |
| 315 | |
| 316 | /* Use ATTRIBUTE_PRINTF when the format specifier must not be NULL. |
| 317 | This was the case for the `printf' format attribute by itself |
| 318 | before GCC 3.3, but as of 3.3 we need to add the `nonnull' |
| 319 | attribute to retain this behavior. */ |
| 320 | #ifndef ATTRIBUTE_PRINTF |
| 321 | #define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) ATTRIBUTE_NONNULL(m) |
| 322 | #define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2) |
| 323 | #define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3) |
| 324 | #define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4) |
| 325 | #define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5) |
| 326 | #define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6) |
| 327 | #endif /* ATTRIBUTE_PRINTF */ |
| 328 | |
| 329 | /* Use ATTRIBUTE_FPTR_PRINTF when the format attribute is to be set on |
| 330 | a function pointer. Format attributes were allowed on function |
| 331 | pointers as of gcc 3.1. */ |
| 332 | #ifndef ATTRIBUTE_FPTR_PRINTF |
| 333 | # if (GCC_VERSION >= 3001) |
| 334 | # define ATTRIBUTE_FPTR_PRINTF(m, n) ATTRIBUTE_PRINTF(m, n) |
| 335 | # else |
| 336 | # define ATTRIBUTE_FPTR_PRINTF(m, n) |
| 337 | # endif /* GNUC >= 3.1 */ |
| 338 | # define ATTRIBUTE_FPTR_PRINTF_1 ATTRIBUTE_FPTR_PRINTF(1, 2) |
| 339 | # define ATTRIBUTE_FPTR_PRINTF_2 ATTRIBUTE_FPTR_PRINTF(2, 3) |
| 340 | # define ATTRIBUTE_FPTR_PRINTF_3 ATTRIBUTE_FPTR_PRINTF(3, 4) |
| 341 | # define ATTRIBUTE_FPTR_PRINTF_4 ATTRIBUTE_FPTR_PRINTF(4, 5) |
| 342 | # define ATTRIBUTE_FPTR_PRINTF_5 ATTRIBUTE_FPTR_PRINTF(5, 6) |
| 343 | #endif /* ATTRIBUTE_FPTR_PRINTF */ |
| 344 | |
| 345 | /* Use ATTRIBUTE_NULL_PRINTF when the format specifier may be NULL. A |
| 346 | NULL format specifier was allowed as of gcc 3.3. */ |
| 347 | #ifndef ATTRIBUTE_NULL_PRINTF |
| 348 | # if (GCC_VERSION >= 3003) |
| 349 | # define ATTRIBUTE_NULL_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) |
| 350 | # else |
| 351 | # define ATTRIBUTE_NULL_PRINTF(m, n) |
| 352 | # endif /* GNUC >= 3.3 */ |
| 353 | # define ATTRIBUTE_NULL_PRINTF_1 ATTRIBUTE_NULL_PRINTF(1, 2) |
| 354 | # define ATTRIBUTE_NULL_PRINTF_2 ATTRIBUTE_NULL_PRINTF(2, 3) |
| 355 | # define ATTRIBUTE_NULL_PRINTF_3 ATTRIBUTE_NULL_PRINTF(3, 4) |
| 356 | # define ATTRIBUTE_NULL_PRINTF_4 ATTRIBUTE_NULL_PRINTF(4, 5) |
| 357 | # define ATTRIBUTE_NULL_PRINTF_5 ATTRIBUTE_NULL_PRINTF(5, 6) |
| 358 | #endif /* ATTRIBUTE_NULL_PRINTF */ |
| 359 | |
| 360 | /* Attribute `sentinel' was valid as of gcc 3.5. */ |
| 361 | #ifndef ATTRIBUTE_SENTINEL |
| 362 | # if (GCC_VERSION >= 3005) |
| 363 | # define ATTRIBUTE_SENTINEL __attribute__ ((__sentinel__)) |
| 364 | # else |
| 365 | # define ATTRIBUTE_SENTINEL |
| 366 | # endif /* GNUC >= 3.5 */ |
| 367 | #endif /* ATTRIBUTE_SENTINEL */ |
| 368 | |
| 369 | |
| 370 | #ifndef ATTRIBUTE_ALIGNED_ALIGNOF |
| 371 | # if (GCC_VERSION >= 3000) |
| 372 | # define ATTRIBUTE_ALIGNED_ALIGNOF(m) __attribute__ ((__aligned__ (__alignof__ (m)))) |
| 373 | # else |
| 374 | # define ATTRIBUTE_ALIGNED_ALIGNOF(m) |
| 375 | # endif /* GNUC >= 3.0 */ |
| 376 | #endif /* ATTRIBUTE_ALIGNED_ALIGNOF */ |
| 377 | |
| 378 | /* Useful for structures whose layout must much some binary specification |
| 379 | regardless of the alignment and padding qualities of the compiler. */ |
| 380 | #ifndef ATTRIBUTE_PACKED |
| 381 | # define ATTRIBUTE_PACKED __attribute__ ((packed)) |
| 382 | #endif |
| 383 | |
| 384 | /* Attribute `hot' and `cold' was valid as of gcc 4.3. */ |
| 385 | #ifndef ATTRIBUTE_COLD |
| 386 | # if (GCC_VERSION >= 4003) |
| 387 | # define ATTRIBUTE_COLD __attribute__ ((__cold__)) |
| 388 | # else |
| 389 | # define ATTRIBUTE_COLD |
| 390 | # endif /* GNUC >= 4.3 */ |
| 391 | #endif /* ATTRIBUTE_COLD */ |
| 392 | #ifndef ATTRIBUTE_HOT |
| 393 | # if (GCC_VERSION >= 4003) |
| 394 | # define ATTRIBUTE_HOT __attribute__ ((__hot__)) |
| 395 | # else |
| 396 | # define ATTRIBUTE_HOT |
| 397 | # endif /* GNUC >= 4.3 */ |
| 398 | #endif /* ATTRIBUTE_HOT */ |
| 399 | |
| 400 | /* We use __extension__ in some places to suppress -pedantic warnings |
| 401 | about GCC extensions. This feature didn't work properly before |
| 402 | gcc 2.8. */ |
| 403 | #if GCC_VERSION < 2008 |
| 404 | #define __extension__ |
| 405 | #endif |
| 406 | |
| 407 | /* This is used to declare a const variable which should be visible |
| 408 | outside of the current compilation unit. Use it as |
| 409 | EXPORTED_CONST int i = 1; |
| 410 | This is because the semantics of const are different in C and C++. |
| 411 | "extern const" is permitted in C but it looks strange, and gcc |
| 412 | warns about it when -Wc++-compat is not used. */ |
| 413 | #ifdef __cplusplus |
| 414 | #define EXPORTED_CONST extern const |
| 415 | #else |
| 416 | #define EXPORTED_CONST const |
| 417 | #endif |
| 418 | |
| 419 | /* Be conservative and only use enum bitfields with C++ or GCC. |
| 420 | FIXME: provide a complete autoconf test for buggy enum bitfields. */ |
| 421 | |
| 422 | #ifdef __cplusplus |
| 423 | #define ENUM_BITFIELD(TYPE) enum TYPE |
| 424 | #elif (GCC_VERSION > 2000) |
| 425 | #define ENUM_BITFIELD(TYPE) __extension__ enum TYPE |
| 426 | #else |
| 427 | #define ENUM_BITFIELD(TYPE) unsigned int |
| 428 | #endif |
| 429 | |
| 430 | #ifdef __cplusplus |
| 431 | } |
| 432 | #endif |
| 433 | |
| 434 | #endif /* ansidecl.h */ |