1 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */ 2 /* Substitute for and wrapper around <langinfo.h>. 3 Copyright (C) 2009-2021 Free Software Foundation, Inc. 4 5 This file is free software: you can redistribute it and/or modify 6 it under the terms of the GNU Lesser General Public License as 7 published by the Free Software Foundation; either version 2.1 of the 8 License, or (at your option) any later version. 9 10 This file is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public License 16 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 17 18 /* 19 * POSIX <langinfo.h> for platforms that lack it or have an incomplete one. 20 * <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/langinfo.h.html> 21 */ 22 23 #ifndef _GL_LANGINFO_H 24 25 #if __GNUC__ >= 3 26 #pragma GCC system_header 27 #endif 28 29 30 /* The include_next requires a split double-inclusion guard. */ 31 #if 0 32 # include_next <langinfo.h> 33 #endif 34 35 #ifndef _GL_LANGINFO_H 36 #define _GL_LANGINFO_H 37 38 39 #if !0 40 41 /* A platform that lacks <langinfo.h>. */ 42 43 /* Assume that it also lacks <nl_types.h> and the nl_item type. */ 44 # if !GNULIB_defined_nl_item 45 typedef int nl_item; 46 # define GNULIB_defined_nl_item 1 47 # endif 48 49 /* nl_langinfo items of the LC_CTYPE category */ 50 # define CODESET 10000 51 /* nl_langinfo items of the LC_NUMERIC category */ 52 # define RADIXCHAR 10001 53 # define DECIMAL_POINT RADIXCHAR 54 # define THOUSEP 10002 55 # define THOUSANDS_SEP THOUSEP 56 # define GROUPING 10114 57 /* nl_langinfo items of the LC_TIME category */ 58 # define D_T_FMT 10003 59 # define D_FMT 10004 60 # define T_FMT 10005 61 # define T_FMT_AMPM 10006 62 # define AM_STR 10007 63 # define PM_STR 10008 64 # define DAY_1 10009 65 # define DAY_2 (DAY_1 + 1) 66 # define DAY_3 (DAY_1 + 2) 67 # define DAY_4 (DAY_1 + 3) 68 # define DAY_5 (DAY_1 + 4) 69 # define DAY_6 (DAY_1 + 5) 70 # define DAY_7 (DAY_1 + 6) 71 # define ABDAY_1 10016 72 # define ABDAY_2 (ABDAY_1 + 1) 73 # define ABDAY_3 (ABDAY_1 + 2) 74 # define ABDAY_4 (ABDAY_1 + 3) 75 # define ABDAY_5 (ABDAY_1 + 4) 76 # define ABDAY_6 (ABDAY_1 + 5) 77 # define ABDAY_7 (ABDAY_1 + 6) 78 # define MON_1 10023 79 # define MON_2 (MON_1 + 1) 80 # define MON_3 (MON_1 + 2) 81 # define MON_4 (MON_1 + 3) 82 # define MON_5 (MON_1 + 4) 83 # define MON_6 (MON_1 + 5) 84 # define MON_7 (MON_1 + 6) 85 # define MON_8 (MON_1 + 7) 86 # define MON_9 (MON_1 + 8) 87 # define MON_10 (MON_1 + 9) 88 # define MON_11 (MON_1 + 10) 89 # define MON_12 (MON_1 + 11) 90 # define ALTMON_1 10200 91 # define ALTMON_2 (ALTMON_1 + 1) 92 # define ALTMON_3 (ALTMON_1 + 2) 93 # define ALTMON_4 (ALTMON_1 + 3) 94 # define ALTMON_5 (ALTMON_1 + 4) 95 # define ALTMON_6 (ALTMON_1 + 5) 96 # define ALTMON_7 (ALTMON_1 + 6) 97 # define ALTMON_8 (ALTMON_1 + 7) 98 # define ALTMON_9 (ALTMON_1 + 8) 99 # define ALTMON_10 (ALTMON_1 + 9) 100 # define ALTMON_11 (ALTMON_1 + 10) 101 # define ALTMON_12 (ALTMON_1 + 11) 102 # define ABMON_1 10035 103 # define ABMON_2 (ABMON_1 + 1) 104 # define ABMON_3 (ABMON_1 + 2) 105 # define ABMON_4 (ABMON_1 + 3) 106 # define ABMON_5 (ABMON_1 + 4) 107 # define ABMON_6 (ABMON_1 + 5) 108 # define ABMON_7 (ABMON_1 + 6) 109 # define ABMON_8 (ABMON_1 + 7) 110 # define ABMON_9 (ABMON_1 + 8) 111 # define ABMON_10 (ABMON_1 + 9) 112 # define ABMON_11 (ABMON_1 + 10) 113 # define ABMON_12 (ABMON_1 + 11) 114 # define ERA 10047 115 # define ERA_D_FMT 10048 116 # define ERA_D_T_FMT 10049 117 # define ERA_T_FMT 10050 118 # define ALT_DIGITS 10051 119 /* nl_langinfo items of the LC_MONETARY category */ 120 # define CRNCYSTR 10052 121 # define CURRENCY_SYMBOL CRNCYSTR 122 # define INT_CURR_SYMBOL 10100 123 # define MON_DECIMAL_POINT 10101 124 # define MON_THOUSANDS_SEP 10102 125 # define MON_GROUPING 10103 126 # define POSITIVE_SIGN 10104 127 # define NEGATIVE_SIGN 10105 128 # define FRAC_DIGITS 10106 129 # define INT_FRAC_DIGITS 10107 130 # define P_CS_PRECEDES 10108 131 # define N_CS_PRECEDES 10109 132 # define P_SEP_BY_SPACE 10110 133 # define N_SEP_BY_SPACE 10111 134 # define P_SIGN_POSN 10112 135 # define N_SIGN_POSN 10113 136 /* nl_langinfo items of the LC_MESSAGES category */ 137 # define YESEXPR 10053 138 # define NOEXPR 10054 139 140 #else 141 142 /* A platform that has <langinfo.h>. */ 143 144 # if !0 145 # define CODESET 10000 146 # define GNULIB_defined_CODESET 1 147 # endif 148 149 # if !0 150 # define T_FMT_AMPM 10006 151 # define GNULIB_defined_T_FMT_AMPM 1 152 # endif 153 154 # if !0 155 # define ALTMON_1 10200 156 # define ALTMON_2 (ALTMON_1 + 1) 157 # define ALTMON_3 (ALTMON_1 + 2) 158 # define ALTMON_4 (ALTMON_1 + 3) 159 # define ALTMON_5 (ALTMON_1 + 4) 160 # define ALTMON_6 (ALTMON_1 + 5) 161 # define ALTMON_7 (ALTMON_1 + 6) 162 # define ALTMON_8 (ALTMON_1 + 7) 163 # define ALTMON_9 (ALTMON_1 + 8) 164 # define ALTMON_10 (ALTMON_1 + 9) 165 # define ALTMON_11 (ALTMON_1 + 10) 166 # define ALTMON_12 (ALTMON_1 + 11) 167 # define GNULIB_defined_ALTMON 1 168 # endif 169 170 # if !0 171 # define ERA 10047 172 # define ERA_D_FMT 10048 173 # define ERA_D_T_FMT 10049 174 # define ERA_T_FMT 10050 175 # define ALT_DIGITS 10051 176 # define GNULIB_defined_ERA 1 177 # endif 178 179 # if !0 180 # define YESEXPR 10053 181 # define NOEXPR 10054 182 # define GNULIB_defined_YESEXPR 1 183 # endif 184 185 #endif 186 187 /* The definitions of _GL_FUNCDECL_RPL etc. are copied here. */ 188 /* C++ compatible function declaration macros. 189 Copyright (C) 2010-2021 Free Software Foundation, Inc. 190 191 This program is free software: you can redistribute it and/or modify it 192 under the terms of the GNU Lesser General Public License as published 193 by the Free Software Foundation; either version 2 of the License, or 194 (at your option) any later version. 195 196 This program is distributed in the hope that it will be useful, 197 but WITHOUT ANY WARRANTY; without even the implied warranty of 198 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 199 Lesser General Public License for more details. 200 201 You should have received a copy of the GNU Lesser General Public License 202 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 203 204 #ifndef _GL_CXXDEFS_H 205 #define _GL_CXXDEFS_H 206 207 /* Begin/end the GNULIB_NAMESPACE namespace. */ 208 #if defined __cplusplus && defined GNULIB_NAMESPACE 209 # define _GL_BEGIN_NAMESPACE namespace GNULIB_NAMESPACE { 210 # define _GL_END_NAMESPACE } 211 #else 212 # define _GL_BEGIN_NAMESPACE 213 # define _GL_END_NAMESPACE 214 #endif 215 216 /* The three most frequent use cases of these macros are: 217 218 * For providing a substitute for a function that is missing on some 219 platforms, but is declared and works fine on the platforms on which 220 it exists: 221 222 #if @GNULIB_FOO@ 223 # if !@HAVE_FOO@ 224 _GL_FUNCDECL_SYS (foo, ...); 225 # endif 226 _GL_CXXALIAS_SYS (foo, ...); 227 _GL_CXXALIASWARN (foo); 228 #elif defined GNULIB_POSIXCHECK 229 ... 230 #endif 231 232 * For providing a replacement for a function that exists on all platforms, 233 but is broken/insufficient and needs to be replaced on some platforms: 234 235 #if @GNULIB_FOO@ 236 # if @REPLACE_FOO@ 237 # if !(defined __cplusplus && defined GNULIB_NAMESPACE) 238 # undef foo 239 # define foo rpl_foo 240 # endif 241 _GL_FUNCDECL_RPL (foo, ...); 242 _GL_CXXALIAS_RPL (foo, ...); 243 # else 244 _GL_CXXALIAS_SYS (foo, ...); 245 # endif 246 _GL_CXXALIASWARN (foo); 247 #elif defined GNULIB_POSIXCHECK 248 ... 249 #endif 250 251 * For providing a replacement for a function that exists on some platforms 252 but is broken/insufficient and needs to be replaced on some of them and 253 is additionally either missing or undeclared on some other platforms: 254 255 #if @GNULIB_FOO@ 256 # if @REPLACE_FOO@ 257 # if !(defined __cplusplus && defined GNULIB_NAMESPACE) 258 # undef foo 259 # define foo rpl_foo 260 # endif 261 _GL_FUNCDECL_RPL (foo, ...); 262 _GL_CXXALIAS_RPL (foo, ...); 263 # else 264 # if !@HAVE_FOO@ or if !@HAVE_DECL_FOO@ 265 _GL_FUNCDECL_SYS (foo, ...); 266 # endif 267 _GL_CXXALIAS_SYS (foo, ...); 268 # endif 269 _GL_CXXALIASWARN (foo); 270 #elif defined GNULIB_POSIXCHECK 271 ... 272 #endif 273 */ 274 275 /* _GL_EXTERN_C declaration; 276 performs the declaration with C linkage. */ 277 #if defined __cplusplus 278 # define _GL_EXTERN_C extern "C" 279 #else 280 # define _GL_EXTERN_C extern 281 #endif 282 283 /* _GL_FUNCDECL_RPL (func, rettype, parameters_and_attributes); 284 declares a replacement function, named rpl_func, with the given prototype, 285 consisting of return type, parameters, and attributes. 286 Example: 287 _GL_FUNCDECL_RPL (open, int, (const char *filename, int flags, ...) 288 _GL_ARG_NONNULL ((1))); 289 */ 290 #define _GL_FUNCDECL_RPL(func,rettype,parameters_and_attributes) \ 291 _GL_FUNCDECL_RPL_1 (rpl_##func, rettype, parameters_and_attributes) 292 #define _GL_FUNCDECL_RPL_1(rpl_func,rettype,parameters_and_attributes) \ 293 _GL_EXTERN_C rettype rpl_func parameters_and_attributes 294 295 /* _GL_FUNCDECL_SYS (func, rettype, parameters_and_attributes); 296 declares the system function, named func, with the given prototype, 297 consisting of return type, parameters, and attributes. 298 Example: 299 _GL_FUNCDECL_SYS (open, int, (const char *filename, int flags, ...) 300 _GL_ARG_NONNULL ((1))); 301 */ 302 #define _GL_FUNCDECL_SYS(func,rettype,parameters_and_attributes) \ 303 _GL_EXTERN_C rettype func parameters_and_attributes 304 305 /* _GL_CXXALIAS_RPL (func, rettype, parameters); 306 declares a C++ alias called GNULIB_NAMESPACE::func 307 that redirects to rpl_func, if GNULIB_NAMESPACE is defined. 308 Example: 309 _GL_CXXALIAS_RPL (open, int, (const char *filename, int flags, ...)); 310 311 Wrapping rpl_func in an object with an inline conversion operator 312 avoids a reference to rpl_func unless GNULIB_NAMESPACE::func is 313 actually used in the program. */ 314 #define _GL_CXXALIAS_RPL(func,rettype,parameters) \ 315 _GL_CXXALIAS_RPL_1 (func, rpl_##func, rettype, parameters) 316 #if defined __cplusplus && defined GNULIB_NAMESPACE 317 # define _GL_CXXALIAS_RPL_1(func,rpl_func,rettype,parameters) \ 318 namespace GNULIB_NAMESPACE \ 319 { \ 320 static const struct _gl_ ## func ## _wrapper \ 321 { \ 322 typedef rettype (*type) parameters; \ 323 \ 324 inline operator type () const \ 325 { \ 326 return ::rpl_func; \ 327 } \ 328 } func = {}; \ 329 } \ 330 _GL_EXTERN_C int _gl_cxxalias_dummy 331 #else 332 # define _GL_CXXALIAS_RPL_1(func,rpl_func,rettype,parameters) \ 333 _GL_EXTERN_C int _gl_cxxalias_dummy 334 #endif 335 336 /* _GL_CXXALIAS_MDA (func, rettype, parameters); 337 is to be used when func is a Microsoft deprecated alias, on native Windows. 338 It declares a C++ alias called GNULIB_NAMESPACE::func 339 that redirects to _func, if GNULIB_NAMESPACE is defined. 340 Example: 341 _GL_CXXALIAS_MDA (open, int, (const char *filename, int flags, ...)); 342 */ 343 #define _GL_CXXALIAS_MDA(func,rettype,parameters) \ 344 _GL_CXXALIAS_RPL_1 (func, _##func, rettype, parameters) 345 346 /* _GL_CXXALIAS_RPL_CAST_1 (func, rpl_func, rettype, parameters); 347 is like _GL_CXXALIAS_RPL_1 (func, rpl_func, rettype, parameters); 348 except that the C function rpl_func may have a slightly different 349 declaration. A cast is used to silence the "invalid conversion" error 350 that would otherwise occur. */ 351 #if defined __cplusplus && defined GNULIB_NAMESPACE 352 # define _GL_CXXALIAS_RPL_CAST_1(func,rpl_func,rettype,parameters) \ 353 namespace GNULIB_NAMESPACE \ 354 { \ 355 static const struct _gl_ ## func ## _wrapper \ 356 { \ 357 typedef rettype (*type) parameters; \ 358 \ 359 inline operator type () const \ 360 { \ 361 return reinterpret_cast<type>(::rpl_func); \ 362 } \ 363 } func = {}; \ 364 } \ 365 _GL_EXTERN_C int _gl_cxxalias_dummy 366 #else 367 # define _GL_CXXALIAS_RPL_CAST_1(func,rpl_func,rettype,parameters) \ 368 _GL_EXTERN_C int _gl_cxxalias_dummy 369 #endif 370 371 /* _GL_CXXALIAS_MDA_CAST (func, rettype, parameters); 372 is like _GL_CXXALIAS_MDA (func, rettype, parameters); 373 except that the C function func may have a slightly different declaration. 374 A cast is used to silence the "invalid conversion" error that would 375 otherwise occur. */ 376 #define _GL_CXXALIAS_MDA_CAST(func,rettype,parameters) \ 377 _GL_CXXALIAS_RPL_CAST_1 (func, _##func, rettype, parameters) 378 379 /* _GL_CXXALIAS_SYS (func, rettype, parameters); 380 declares a C++ alias called GNULIB_NAMESPACE::func 381 that redirects to the system provided function func, if GNULIB_NAMESPACE 382 is defined. 383 Example: 384 _GL_CXXALIAS_SYS (open, int, (const char *filename, int flags, ...)); 385 386 Wrapping func in an object with an inline conversion operator 387 avoids a reference to func unless GNULIB_NAMESPACE::func is 388 actually used in the program. */ 389 #if defined __cplusplus && defined GNULIB_NAMESPACE 390 # define _GL_CXXALIAS_SYS(func,rettype,parameters) \ 391 namespace GNULIB_NAMESPACE \ 392 { \ 393 static const struct _gl_ ## func ## _wrapper \ 394 { \ 395 typedef rettype (*type) parameters; \ 396 \ 397 inline operator type () const \ 398 { \ 399 return ::func; \ 400 } \ 401 } func = {}; \ 402 } \ 403 _GL_EXTERN_C int _gl_cxxalias_dummy 404 #else 405 # define _GL_CXXALIAS_SYS(func,rettype,parameters) \ 406 _GL_EXTERN_C int _gl_cxxalias_dummy 407 #endif 408 409 /* _GL_CXXALIAS_SYS_CAST (func, rettype, parameters); 410 is like _GL_CXXALIAS_SYS (func, rettype, parameters); 411 except that the C function func may have a slightly different declaration. 412 A cast is used to silence the "invalid conversion" error that would 413 otherwise occur. */ 414 #if defined __cplusplus && defined GNULIB_NAMESPACE 415 # define _GL_CXXALIAS_SYS_CAST(func,rettype,parameters) \ 416 namespace GNULIB_NAMESPACE \ 417 { \ 418 static const struct _gl_ ## func ## _wrapper \ 419 { \ 420 typedef rettype (*type) parameters; \ 421 \ 422 inline operator type () const \ 423 { \ 424 return reinterpret_cast<type>(::func); \ 425 } \ 426 } func = {}; \ 427 } \ 428 _GL_EXTERN_C int _gl_cxxalias_dummy 429 #else 430 # define _GL_CXXALIAS_SYS_CAST(func,rettype,parameters) \ 431 _GL_EXTERN_C int _gl_cxxalias_dummy 432 #endif 433 434 /* _GL_CXXALIAS_SYS_CAST2 (func, rettype, parameters, rettype2, parameters2); 435 is like _GL_CXXALIAS_SYS (func, rettype, parameters); 436 except that the C function is picked among a set of overloaded functions, 437 namely the one with rettype2 and parameters2. Two consecutive casts 438 are used to silence the "cannot find a match" and "invalid conversion" 439 errors that would otherwise occur. */ 440 #if defined __cplusplus && defined GNULIB_NAMESPACE 441 /* The outer cast must be a reinterpret_cast. 442 The inner cast: When the function is defined as a set of overloaded 443 functions, it works as a static_cast<>, choosing the designated variant. 444 When the function is defined as a single variant, it works as a 445 reinterpret_cast<>. The parenthesized cast syntax works both ways. */ 446 # define _GL_CXXALIAS_SYS_CAST2(func,rettype,parameters,rettype2,parameters2) \ 447 namespace GNULIB_NAMESPACE \ 448 { \ 449 static const struct _gl_ ## func ## _wrapper \ 450 { \ 451 typedef rettype (*type) parameters; \ 452 \ 453 inline operator type () const \ 454 { \ 455 return reinterpret_cast<type>((rettype2 (*) parameters2)(::func)); \ 456 } \ 457 } func = {}; \ 458 } \ 459 _GL_EXTERN_C int _gl_cxxalias_dummy 460 #else 461 # define _GL_CXXALIAS_SYS_CAST2(func,rettype,parameters,rettype2,parameters2) \ 462 _GL_EXTERN_C int _gl_cxxalias_dummy 463 #endif 464 465 /* _GL_CXXALIASWARN (func); 466 causes a warning to be emitted when ::func is used but not when 467 GNULIB_NAMESPACE::func is used. func must be defined without overloaded 468 variants. */ 469 #if defined __cplusplus && defined GNULIB_NAMESPACE 470 # define _GL_CXXALIASWARN(func) \ 471 _GL_CXXALIASWARN_1 (func, GNULIB_NAMESPACE) 472 # define _GL_CXXALIASWARN_1(func,namespace) \ 473 _GL_CXXALIASWARN_2 (func, namespace) 474 /* To work around GCC bug <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43881>, 475 we enable the warning only when not optimizing. */ 476 # if !(defined __GNUC__ && !defined __clang__ && __OPTIMIZE__) 477 # define _GL_CXXALIASWARN_2(func,namespace) \ 478 _GL_WARN_ON_USE (func, \ 479 "The symbol ::" #func " refers to the system function. " \ 480 "Use " #namespace "::" #func " instead.") 481 # elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING 482 # define _GL_CXXALIASWARN_2(func,namespace) \ 483 extern __typeof__ (func) func 484 # else 485 # define _GL_CXXALIASWARN_2(func,namespace) \ 486 _GL_EXTERN_C int _gl_cxxalias_dummy 487 # endif 488 #else 489 # define _GL_CXXALIASWARN(func) \ 490 _GL_EXTERN_C int _gl_cxxalias_dummy 491 #endif 492 493 /* _GL_CXXALIASWARN1 (func, rettype, parameters_and_attributes); 494 causes a warning to be emitted when the given overloaded variant of ::func 495 is used but not when GNULIB_NAMESPACE::func is used. */ 496 #if defined __cplusplus && defined GNULIB_NAMESPACE 497 # define _GL_CXXALIASWARN1(func,rettype,parameters_and_attributes) \ 498 _GL_CXXALIASWARN1_1 (func, rettype, parameters_and_attributes, \ 499 GNULIB_NAMESPACE) 500 # define _GL_CXXALIASWARN1_1(func,rettype,parameters_and_attributes,namespace) \ 501 _GL_CXXALIASWARN1_2 (func, rettype, parameters_and_attributes, namespace) 502 /* To work around GCC bug <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43881>, 503 we enable the warning only when not optimizing. */ 504 # if !(defined __GNUC__ && !defined __clang__ && __OPTIMIZE__) 505 # define _GL_CXXALIASWARN1_2(func,rettype,parameters_and_attributes,namespace) \ 506 _GL_WARN_ON_USE_CXX (func, rettype, rettype, parameters_and_attributes, \ 507 "The symbol ::" #func " refers to the system function. " \ 508 "Use " #namespace "::" #func " instead.") 509 # else 510 # define _GL_CXXALIASWARN1_2(func,rettype,parameters_and_attributes,namespace) \ 511 _GL_EXTERN_C int _gl_cxxalias_dummy 512 # endif 513 #else 514 # define _GL_CXXALIASWARN1(func,rettype,parameters_and_attributes) \ 515 _GL_EXTERN_C int _gl_cxxalias_dummy 516 #endif 517 518 #endif /* _GL_CXXDEFS_H */ 519 520 /* The definition of _GL_WARN_ON_USE is copied here. */ 521 /* A C macro for emitting warnings if a function is used. 522 Copyright (C) 2010-2021 Free Software Foundation, Inc. 523 524 This program is free software: you can redistribute it and/or modify it 525 under the terms of the GNU Lesser General Public License as published 526 by the Free Software Foundation; either version 2 of the License, or 527 (at your option) any later version. 528 529 This program is distributed in the hope that it will be useful, 530 but WITHOUT ANY WARRANTY; without even the implied warranty of 531 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 532 Lesser General Public License for more details. 533 534 You should have received a copy of the GNU Lesser General Public License 535 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 536 537 /* _GL_WARN_ON_USE (function, "literal string") issues a declaration 538 for FUNCTION which will then trigger a compiler warning containing 539 the text of "literal string" anywhere that function is called, if 540 supported by the compiler. If the compiler does not support this 541 feature, the macro expands to an unused extern declaration. 542 543 _GL_WARN_ON_USE_ATTRIBUTE ("literal string") expands to the 544 attribute used in _GL_WARN_ON_USE. If the compiler does not support 545 this feature, it expands to empty. 546 547 These macros are useful for marking a function as a potential 548 portability trap, with the intent that "literal string" include 549 instructions on the replacement function that should be used 550 instead. 551 _GL_WARN_ON_USE is for functions with 'extern' linkage. 552 _GL_WARN_ON_USE_ATTRIBUTE is for functions with 'static' or 'inline' 553 linkage. 554 555 However, one of the reasons that a function is a portability trap is 556 if it has the wrong signature. Declaring FUNCTION with a different 557 signature in C is a compilation error, so this macro must use the 558 same type as any existing declaration so that programs that avoid 559 the problematic FUNCTION do not fail to compile merely because they 560 included a header that poisoned the function. But this implies that 561 _GL_WARN_ON_USE is only safe to use if FUNCTION is known to already 562 have a declaration. Use of this macro implies that there must not 563 be any other macro hiding the declaration of FUNCTION; but 564 undefining FUNCTION first is part of the poisoning process anyway 565 (although for symbols that are provided only via a macro, the result 566 is a compilation error rather than a warning containing 567 "literal string"). Also note that in C++, it is only safe to use if 568 FUNCTION has no overloads. 569 570 For an example, it is possible to poison 'getline' by: 571 - adding a call to gl_WARN_ON_USE_PREPARE([[#include <stdio.h>]], 572 [getline]) in configure.ac, which potentially defines 573 HAVE_RAW_DECL_GETLINE 574 - adding this code to a header that wraps the system <stdio.h>: 575 #undef getline 576 #if HAVE_RAW_DECL_GETLINE 577 _GL_WARN_ON_USE (getline, "getline is required by POSIX 2008, but" 578 "not universally present; use the gnulib module getline"); 579 #endif 580 581 It is not possible to directly poison global variables. But it is 582 possible to write a wrapper accessor function, and poison that 583 (less common usage, like &environ, will cause a compilation error 584 rather than issue the nice warning, but the end result of informing 585 the developer about their portability problem is still achieved): 586 #if HAVE_RAW_DECL_ENVIRON 587 static char *** 588 rpl_environ (void) { return &environ; } 589 _GL_WARN_ON_USE (rpl_environ, "environ is not always properly declared"); 590 # undef environ 591 # define environ (*rpl_environ ()) 592 #endif 593 or better (avoiding contradictory use of 'static' and 'extern'): 594 #if HAVE_RAW_DECL_ENVIRON 595 static char *** 596 _GL_WARN_ON_USE_ATTRIBUTE ("environ is not always properly declared") 597 rpl_environ (void) { return &environ; } 598 # undef environ 599 # define environ (*rpl_environ ()) 600 #endif 601 */ 602 #ifndef _GL_WARN_ON_USE 603 604 # if 4 < __GNUC__ || (__GNUC__ == 4 && 3 <= __GNUC_MINOR__) 605 /* A compiler attribute is available in gcc versions 4.3.0 and later. */ 606 # define _GL_WARN_ON_USE(function, message) \ 607 extern __typeof__ (function) function __attribute__ ((__warning__ (message))) 608 # define _GL_WARN_ON_USE_ATTRIBUTE(message) \ 609 __attribute__ ((__warning__ (message))) 610 # elif __clang_major__ >= 4 611 /* Another compiler attribute is available in clang. */ 612 # define _GL_WARN_ON_USE(function, message) \ 613 extern __typeof__ (function) function \ 614 __attribute__ ((__diagnose_if__ (1, message, "warning"))) 615 # define _GL_WARN_ON_USE_ATTRIBUTE(message) \ 616 __attribute__ ((__diagnose_if__ (1, message, "warning"))) 617 # elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING 618 /* Verify the existence of the function. */ 619 # define _GL_WARN_ON_USE(function, message) \ 620 extern __typeof__ (function) function 621 # define _GL_WARN_ON_USE_ATTRIBUTE(message) 622 # else /* Unsupported. */ 623 # define _GL_WARN_ON_USE(function, message) \ 624 _GL_WARN_EXTERN_C int _gl_warn_on_use 625 # define _GL_WARN_ON_USE_ATTRIBUTE(message) 626 # endif 627 #endif 628 629 /* _GL_WARN_ON_USE_CXX (function, rettype_gcc, rettype_clang, parameters_and_attributes, "message") 630 is like _GL_WARN_ON_USE (function, "message"), except that in C++ mode the 631 function is declared with the given prototype, consisting of return type, 632 parameters, and attributes. 633 This variant is useful for overloaded functions in C++. _GL_WARN_ON_USE does 634 not work in this case. */ 635 #ifndef _GL_WARN_ON_USE_CXX 636 # if !defined __cplusplus 637 # define _GL_WARN_ON_USE_CXX(function,rettype_gcc,rettype_clang,parameters_and_attributes,msg) \ 638 _GL_WARN_ON_USE (function, msg) 639 # else 640 # if 4 < __GNUC__ || (__GNUC__ == 4 && 3 <= __GNUC_MINOR__) 641 /* A compiler attribute is available in gcc versions 4.3.0 and later. */ 642 # define _GL_WARN_ON_USE_CXX(function,rettype_gcc,rettype_clang,parameters_and_attributes,msg) \ 643 extern rettype_gcc function parameters_and_attributes \ 644 __attribute__ ((__warning__ (msg))) 645 # elif __clang_major__ >= 4 646 /* Another compiler attribute is available in clang. */ 647 # define _GL_WARN_ON_USE_CXX(function,rettype_gcc,rettype_clang,parameters_and_attributes,msg) \ 648 extern rettype_clang function parameters_and_attributes \ 649 __attribute__ ((__diagnose_if__ (1, msg, "warning"))) 650 # elif __GNUC__ >= 3 && GNULIB_STRICT_CHECKING 651 /* Verify the existence of the function. */ 652 # define _GL_WARN_ON_USE_CXX(function,rettype_gcc,rettype_clang,parameters_and_attributes,msg) \ 653 extern rettype_gcc function parameters_and_attributes 654 # else /* Unsupported. */ 655 # define _GL_WARN_ON_USE_CXX(function,rettype_gcc,rettype_clang,parameters_and_attributes,msg) \ 656 _GL_WARN_EXTERN_C int _gl_warn_on_use 657 # endif 658 # endif 659 #endif 660 661 /* _GL_WARN_EXTERN_C declaration; 662 performs the declaration with C linkage. */ 663 #ifndef _GL_WARN_EXTERN_C 664 # if defined __cplusplus 665 # define _GL_WARN_EXTERN_C extern "C" 666 # else 667 # define _GL_WARN_EXTERN_C extern 668 # endif 669 #endif 670 671 /* Declare overridden functions. */ 672 673 674 /* Return a piece of locale dependent information. 675 Note: The difference between nl_langinfo (CODESET) and locale_charset () 676 is that the latter normalizes the encoding names to GNU conventions. */ 677 678 #if 1 679 # if 0 680 # if !(defined __cplusplus && defined GNULIB_NAMESPACE) 681 # undef nl_langinfo 682 # define nl_langinfo rpl_nl_langinfo 683 # endif 684 _GL_FUNCDECL_RPL (nl_langinfo, char *, (nl_item item)); 685 _GL_CXXALIAS_RPL (nl_langinfo, char *, (nl_item item)); 686 # else 687 # if !0 688 _GL_FUNCDECL_SYS (nl_langinfo, char *, (nl_item item)); 689 # endif 690 _GL_CXXALIAS_SYS (nl_langinfo, char *, (nl_item item)); 691 # endif 692 _GL_CXXALIASWARN (nl_langinfo); 693 #elif defined GNULIB_POSIXCHECK 694 # undef nl_langinfo 695 # if HAVE_RAW_DECL_NL_LANGINFO 696 _GL_WARN_ON_USE (nl_langinfo, "nl_langinfo is not portable - " 697 "use gnulib module nl_langinfo for portability"); 698 # endif 699 #endif 700 701 702 #endif /* _GL_LANGINFO_H */ 703 #endif /* _GL_LANGINFO_H */ 704