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
109fprintf (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
116printf (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
123fprintf (__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
135printf (__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
152vprintf (__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
163vfprintf (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
172dprintf (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
179dprintf (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
195vdprintf (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 *
292gets (__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 *
305fgets (__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
322fread (__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 *
342fgets_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
362fread_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. */