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The C and C++ Include Header Files
cat -n /usr/include/x86_64-linux-gnu/bits/stdio2.h
1 /* Checking macros for stdio functions. 2 Copyright (C) 2004-2026 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library 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 GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 #ifndef _BITS_STDIO2_H 20 #define _BITS_STDIO2_H 1 21 22 #ifndef _STDIO_H 23 # error "Never include <bits/stdio2.h> directly; use <stdio.h> instead." 24 #endif 25 26 #ifdef __va_arg_pack 27 __fortify_function int 28 __NTH (sprintf (char *__restrict __s, const char *__restrict __fmt, ...)) 29 { 30 return __builtin___sprintf_chk (__s, __USE_FORTIFY_LEVEL - 1, 31 __glibc_objsize (__s), __fmt, 32 __va_arg_pack ()); 33 } 34 #elif __fortify_use_clang 35 /* clang does not have __va_arg_pack, so defer to va_arg version. */ 36 __fortify_function_error_function __attribute_overloadable__ int 37 __NTH (sprintf (__fortify_clang_overload_arg (char *, __restrict, __s), 38 const char *__restrict __fmt, ...)) 39 { 40 __gnuc_va_list __fortify_ap; 41 __builtin_va_start (__fortify_ap, __fmt); 42 int __r = __builtin___vsprintf_chk (__s, __USE_FORTIFY_LEVEL - 1, 43 __glibc_objsize (__s), __fmt, 44 __fortify_ap); 45 __builtin_va_end (__fortify_ap); 46 return __r; 47 } 48 #elif !defined __cplusplus 49 # define sprintf(str, ...) \ 50 __builtin___sprintf_chk (str, __USE_FORTIFY_LEVEL - 1, \ 51 __glibc_objsize (str), __VA_ARGS__) 52 #endif 53 54 __fortify_function __attribute_overloadable__ int 55 __NTH (vsprintf (__fortify_clang_overload_arg (char *, __restrict, __s), 56 const char *__restrict __fmt, __gnuc_va_list __ap)) 57 { 58 return __builtin___vsprintf_chk (__s, __USE_FORTIFY_LEVEL - 1, 59 __glibc_objsize (__s), __fmt, __ap); 60 } 61 62 #if defined __USE_ISOC99 || defined __USE_UNIX98 63 # ifdef __va_arg_pack 64 __fortify_function int 65 __NTH (snprintf (char *__restrict __s, size_t __n, 66 const char *__restrict __fmt, ...)) 67 { 68 return __builtin___snprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1, 69 __glibc_objsize (__s), __fmt, 70 __va_arg_pack ()); 71 } 72 # elif __fortify_use_clang 73 /* clang does not have __va_arg_pack, so defer to va_arg version. */ 74 __fortify_function_error_function __attribute_overloadable__ int 75 __NTH (snprintf (__fortify_clang_overload_arg (char *, __restrict, __s), 76 size_t __n, const char *__restrict __fmt, ...)) 77 { 78 __gnuc_va_list __fortify_ap; 79 __builtin_va_start (__fortify_ap, __fmt); 80 int __r = __builtin___vsnprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1, 81 __glibc_objsize (__s), __fmt, 82 __fortify_ap); 83 __builtin_va_end (__fortify_ap); 84 return __r; 85 } 86 # elif !defined __cplusplus 87 # define snprintf(str, len, ...) \ 88 __builtin___snprintf_chk (str, len, __USE_FORTIFY_LEVEL - 1, \ 89 __glibc_objsize (str), __VA_ARGS__) 90 # endif 91 92 __fortify_function __attribute_overloadable__ int 93 __NTH (vsnprintf (__fortify_clang_overload_arg (char *, __restrict, __s), 94 size_t __n, const char *__restrict __fmt, 95 __gnuc_va_list __ap)) 96 __fortify_clang_warning (__fortify_clang_bos_static_lt (__n, __s), 97 "call to vsnprintf may overflow the destination " 98 "buffer") 99 { 100 return __builtin___vsnprintf_chk (__s, __n, __USE_FORTIFY_LEVEL - 1, 101 __glibc_objsize (__s), __fmt, __ap); 102 } 103 104 #endif 105 106 #if __USE_FORTIFY_LEVEL > 1 107 # ifdef __va_arg_pack 108 __fortify_function __nonnull ((1)) int 109 fprintf (FILE *__restrict __stream, const char *__restrict __fmt, ...) 110 { 111 return __fprintf_chk (__stream, __USE_FORTIFY_LEVEL - 1, __fmt, 112 __va_arg_pack ()); 113 } 114 115 __fortify_function int 116 printf (const char *__restrict __fmt, ...) 117 { 118 return __printf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __va_arg_pack ()); 119 } 120 # elif __fortify_use_clang 121 /* clang does not have __va_arg_pack, so defer to va_arg version. */ 122 __fortify_function_error_function __attribute_overloadable__ __nonnull ((1)) int 123 fprintf (__fortify_clang_overload_arg (FILE *, __restrict, __stream), 124 const char *__restrict __fmt, ...) 125 { 126 __gnuc_va_list __fortify_ap; 127 __builtin_va_start (__fortify_ap, __fmt); 128 int __r = __builtin___vfprintf_chk (__stream, __USE_FORTIFY_LEVEL - 1, 129 __fmt, __fortify_ap); 130 __builtin_va_end (__fortify_ap); 131 return __r; 132 } 133 134 __fortify_function_error_function __attribute_overloadable__ int 135 printf (__fortify_clang_overload_arg (const char *, __restrict, __fmt), ...) 136 { 137 __gnuc_va_list __fortify_ap; 138 __builtin_va_start (__fortify_ap, __fmt); 139 int __r = __builtin___vprintf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, 140 __fortify_ap); 141 __builtin_va_end (__fortify_ap); 142 return __r; 143 } 144 # elif !defined __cplusplus 145 # define printf(...) \ 146 __printf_chk (__USE_FORTIFY_LEVEL - 1, __VA_ARGS__) 147 # define fprintf(stream, ...) \ 148 __fprintf_chk (stream, __USE_FORTIFY_LEVEL - 1, __VA_ARGS__) 149 # endif 150 151 __fortify_function __attribute_overloadable__ int 152 vprintf (__fortify_clang_overload_arg (const char *, __restrict, __fmt), 153 __gnuc_va_list __ap) 154 { 155 #ifdef __USE_EXTERN_INLINES 156 return __vfprintf_chk (stdout, __USE_FORTIFY_LEVEL - 1, __fmt, __ap); 157 #else 158 return __vprintf_chk (__USE_FORTIFY_LEVEL - 1, __fmt, __ap); 159 #endif 160 } 161 162 __fortify_function __nonnull ((1)) int 163 vfprintf (FILE *__restrict __stream, 164 const char *__restrict __fmt, __gnuc_va_list __ap) 165 { 166 return __vfprintf_chk (__stream, __USE_FORTIFY_LEVEL - 1, __fmt, __ap); 167 } 168 169 # ifdef __USE_XOPEN2K8 170 # ifdef __va_arg_pack 171 __fortify_function int 172 dprintf (int __fd, const char *__restrict __fmt, ...) 173 { 174 return __dprintf_chk (__fd, __USE_FORTIFY_LEVEL - 1, __fmt, 175 __va_arg_pack ()); 176 } 177 # elif __fortify_use_clang 178 __fortify_function_error_function __attribute_overloadable__ int 179 dprintf (int __fd, __fortify_clang_overload_arg (const char *, __restrict, 180 __fmt), ...) 181 { 182 __gnuc_va_list __fortify_ap; 183 __builtin_va_start (__fortify_ap, __fmt); 184 int __r = __vdprintf_chk (__fd, __USE_FORTIFY_LEVEL - 1, __fmt, 185 __fortify_ap); 186 __builtin_va_end (__fortify_ap); 187 return __r; 188 } 189 # elif !defined __cplusplus 190 # define dprintf(fd, ...) \ 191 __dprintf_chk (fd, __USE_FORTIFY_LEVEL - 1, __VA_ARGS__) 192 # endif 193 194 __fortify_function int 195 vdprintf (int __fd, const char *__restrict __fmt, __gnuc_va_list __ap) 196 { 197 return __vdprintf_chk (__fd, __USE_FORTIFY_LEVEL - 1, __fmt, __ap); 198 } 199 # endif 200 201 # ifdef __USE_GNU 202 # ifdef __va_arg_pack 203 __fortify_function int 204 __NTH (asprintf (char **__restrict __ptr, const char *__restrict __fmt, ...)) 205 { 206 return __asprintf_chk (__ptr, __USE_FORTIFY_LEVEL - 1, __fmt, 207 __va_arg_pack ()); 208 } 209 210 __fortify_function int 211 __NTH (__asprintf (char **__restrict __ptr, const char *__restrict __fmt, 212 ...)) 213 { 214 return __asprintf_chk (__ptr, __USE_FORTIFY_LEVEL - 1, __fmt, 215 __va_arg_pack ()); 216 } 217 218 __fortify_function int 219 __NTH (obstack_printf (struct obstack *__restrict __obstack, 220 const char *__restrict __fmt, ...)) 221 { 222 return __obstack_printf_chk (__obstack, __USE_FORTIFY_LEVEL - 1, __fmt, 223 __va_arg_pack ()); 224 } 225 # elif __fortify_use_clang 226 __fortify_function_error_function __attribute_overloadable__ int 227 __NTH (asprintf (__fortify_clang_overload_arg (char **, __restrict, __ptr), 228 const char *__restrict __fmt, ...)) 229 { 230 __gnuc_va_list __fortify_ap; 231 __builtin_va_start (__fortify_ap, __fmt); 232 int __r = __vasprintf_chk (__ptr, __USE_FORTIFY_LEVEL - 1, __fmt, 233 __fortify_ap); 234 __builtin_va_end (__fortify_ap); 235 return __r; 236 } 237 238 __fortify_function_error_function __attribute_overloadable__ int 239 __NTH (__asprintf (__fortify_clang_overload_arg (char **, __restrict, __ptr), 240 const char *__restrict __fmt, ...)) 241 { 242 __gnuc_va_list __fortify_ap; 243 __builtin_va_start (__fortify_ap, __fmt); 244 int __r = __vasprintf_chk (__ptr, __USE_FORTIFY_LEVEL - 1, __fmt, 245 __fortify_ap); 246 __builtin_va_end (__fortify_ap); 247 return __r; 248 } 249 250 __fortify_function_error_function __attribute_overloadable__ int 251 __NTH (obstack_printf (__fortify_clang_overload_arg (struct obstack *, 252 __restrict, __obstack), 253 const char *__restrict __fmt, ...)) 254 { 255 __gnuc_va_list __fortify_ap; 256 __builtin_va_start (__fortify_ap, __fmt); 257 int __r = __obstack_vprintf_chk (__obstack, __USE_FORTIFY_LEVEL - 1, 258 __fmt, __fortify_ap); 259 __builtin_va_end (__fortify_ap); 260 return __r; 261 } 262 # elif !defined __cplusplus 263 # define asprintf(ptr, ...) \ 264 __asprintf_chk (ptr, __USE_FORTIFY_LEVEL - 1, __VA_ARGS__) 265 # define __asprintf(ptr, ...) \ 266 __asprintf_chk (ptr, __USE_FORTIFY_LEVEL - 1, __VA_ARGS__) 267 # define obstack_printf(obstack, ...) \ 268 __obstack_printf_chk (obstack, __USE_FORTIFY_LEVEL - 1, __VA_ARGS__) 269 # endif 270 271 __fortify_function int 272 __NTH (vasprintf (char **__restrict __ptr, const char *__restrict __fmt, 273 __gnuc_va_list __ap)) 274 { 275 return __vasprintf_chk (__ptr, __USE_FORTIFY_LEVEL - 1, __fmt, __ap); 276 } 277 278 __fortify_function int 279 __NTH (obstack_vprintf (struct obstack *__restrict __obstack, 280 const char *__restrict __fmt, __gnuc_va_list __ap)) 281 { 282 return __obstack_vprintf_chk (__obstack, __USE_FORTIFY_LEVEL - 1, __fmt, 283 __ap); 284 } 285 286 # endif 287 288 #endif 289 290 #if __GLIBC_USE (DEPRECATED_GETS) 291 __fortify_function __wur __attribute_overloadable__ char * 292 gets (__fortify_clang_overload_arg (char *, , __str)) 293 __fortify_clang_warning (__glibc_objsize (__str) == (size_t) -1, 294 "please use fgets or getline instead, gets " 295 "can not specify buffer size") 296 { 297 if (__glibc_objsize (__str) != (size_t) -1) 298 return __gets_chk (__str, __glibc_objsize (__str)); 299 return __gets_warn (__str); 300 } 301 #endif 302 303 __fortify_function __wur __fortified_attr_access (__write_only__, 1, 2) 304 __nonnull ((3)) __attribute_overloadable__ char * 305 fgets (__fortify_clang_overload_arg (char *, __restrict, __s), int __n, 306 FILE *__restrict __stream) 307 __fortify_clang_warning (__fortify_clang_bos_static_lt (__n, __s) && __n > 0, 308 "fgets called with bigger size than length of " 309 "destination buffer") 310 { 311 size_t __sz = __glibc_objsize (__s); 312 if (__glibc_safe_or_unknown_len (__n, sizeof (char), __sz)) 313 return __fgets_alias (__s, __n, __stream); 314 #if !__fortify_use_clang 315 if (__glibc_unsafe_len (__n, sizeof (char), __sz)) 316 return __fgets_chk_warn (__s, __sz, __n, __stream); 317 #endif 318 return __fgets_chk (__s, __sz, __n, __stream); 319 } 320 321 __fortify_function __wur __nonnull ((4)) __attribute_overloadable__ size_t 322 fread (__fortify_clang_overload_arg (void *, __restrict, __ptr), 323 size_t __size, size_t __n, FILE *__restrict __stream) 324 __fortify_clang_warning (__fortify_clang_bos0_static_lt (__size * __n, __ptr) 325 && !__fortify_clang_mul_may_overflow (__size, __n), 326 "fread called with bigger size * n than length " 327 "of destination buffer") 328 { 329 size_t __sz = __glibc_objsize0 (__ptr); 330 if (__glibc_safe_or_unknown_len (__n, __size, __sz)) 331 return __fread_alias (__ptr, __size, __n, __stream); 332 #if !__fortify_use_clang 333 if (__glibc_unsafe_len (__n, __size, __sz)) 334 return __fread_chk_warn (__ptr, __sz, __size, __n, __stream); 335 #endif 336 return __fread_chk (__ptr, __sz, __size, __n, __stream); 337 } 338 339 #ifdef __USE_GNU 340 __fortify_function __wur __fortified_attr_access (__write_only__, 1, 2) 341 __nonnull ((3)) __attribute_overloadable__ char * 342 fgets_unlocked (__fortify_clang_overload_arg (char *, __restrict, __s), 343 int __n, FILE *__restrict __stream) 344 __fortify_clang_warning (__fortify_clang_bos_static_lt (__n, __s) && __n > 0, 345 "fgets called with bigger size than length of " 346 "destination buffer") 347 { 348 size_t __sz = __glibc_objsize (__s); 349 if (__glibc_safe_or_unknown_len (__n, sizeof (char), __sz)) 350 return __fgets_unlocked_alias (__s, __n, __stream); 351 #if !__fortify_use_clang 352 if (__glibc_unsafe_len (__n, sizeof (char), __sz)) 353 return __fgets_unlocked_chk_warn (__s, __sz, __n, __stream); 354 #endif 355 return __fgets_unlocked_chk (__s, __sz, __n, __stream); 356 } 357 #endif 358 359 #ifdef __USE_MISC 360 # undef fread_unlocked 361 __fortify_function __wur __nonnull ((4)) __attribute_overloadable__ size_t 362 fread_unlocked (__fortify_clang_overload_arg0 (void *, __restrict, __ptr), 363 size_t __size, size_t __n, FILE *__restrict __stream) 364 __fortify_clang_warning (__fortify_clang_bos0_static_lt (__size * __n, __ptr) 365 && !__fortify_clang_mul_may_overflow (__size, __n), 366 "fread_unlocked called with bigger size * n than " 367 "length of destination buffer") 368 { 369 size_t __sz = __glibc_objsize0 (__ptr); 370 if (__glibc_safe_or_unknown_len (__n, __size, __sz)) 371 { 372 # ifdef __USE_EXTERN_INLINES 373 if (__builtin_constant_p (__size) 374 && __builtin_constant_p (__n) 375 && (__size | __n) < (((size_t) 1) << (8 * sizeof (size_t) / 2)) 376 && __size * __n <= 8) 377 { 378 size_t __cnt = __size * __n; 379 char *__cptr = (char *) __ptr; 380 if (__cnt == 0) 381 return 0; 382 383 for (; __cnt > 0; --__cnt) 384 { 385 int __c = getc_unlocked (__stream); 386 if (__c == EOF) 387 break; 388 *__cptr++ = __c; 389 } 390 return (__cptr - (char *) __ptr) / __size; 391 } 392 # endif 393 return __fread_unlocked_alias (__ptr, __size, __n, __stream); 394 } 395 # if !__fortify_use_clang 396 if (__glibc_unsafe_len (__n, __size, __sz)) 397 return __fread_unlocked_chk_warn (__ptr, __sz, __size, __n, __stream); 398 # endif 399 return __fread_unlocked_chk (__ptr, __sz, __size, __n, __stream); 400 401 } 402 #endif 403 404 #endif /* bits/stdio2.h. */
