xref: /freebsd/include/stdio.h (revision e9ac41698b2f322d55ccf9da50a3596edb2c1800)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * Chris Torek.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #ifndef	_STDIO_H_
36 #define	_STDIO_H_
37 
38 #include <sys/cdefs.h>
39 #include <sys/_null.h>
40 #include <sys/_types.h>
41 
42 __NULLABILITY_PRAGMA_PUSH
43 
44 typedef	__off_t		fpos_t;
45 
46 #ifndef _SIZE_T_DECLARED
47 typedef	__size_t	size_t;
48 #define	_SIZE_T_DECLARED
49 #endif
50 
51 #ifndef _RSIZE_T_DEFINED
52 #define _RSIZE_T_DEFINED
53 typedef size_t rsize_t;
54 #endif
55 
56 #if __POSIX_VISIBLE >= 200809
57 #ifndef _OFF_T_DECLARED
58 #define	_OFF_T_DECLARED
59 typedef	__off_t		off_t;
60 #endif
61 #ifndef _SSIZE_T_DECLARED
62 #define	_SSIZE_T_DECLARED
63 typedef	__ssize_t	ssize_t;
64 #endif
65 #endif
66 
67 #ifndef _OFF64_T_DECLARED
68 #define	_OFF64_T_DECLARED
69 typedef	__off64_t	off64_t;
70 #endif
71 
72 #if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE
73 #ifndef _VA_LIST_DECLARED
74 typedef	__va_list	va_list;
75 #define	_VA_LIST_DECLARED
76 #endif
77 #endif
78 
79 #define	_FSTDIO			/* Define for new stdio with functions. */
80 
81 /*
82  * NB: to fit things in six character monocase externals, the stdio
83  * code uses the prefix `__s' for stdio objects, typically followed
84  * by a three-character attempt at a mnemonic.
85  */
86 
87 /* stdio buffers */
88 struct __sbuf {
89 	unsigned char *_base;
90 	int	_size;
91 };
92 
93 /*
94  * stdio state variables.
95  *
96  * The following always hold:
97  *
98  *	if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR),
99  *		_lbfsize is -_bf._size, else _lbfsize is 0
100  *	if _flags&__SRD, _w is 0
101  *	if _flags&__SWR, _r is 0
102  *
103  * This ensures that the getc and putc macros (or inline functions) never
104  * try to write or read from a file that is in `read' or `write' mode.
105  * (Moreover, they can, and do, automatically switch from read mode to
106  * write mode, and back, on "r+" and "w+" files.)
107  *
108  * _lbfsize is used only to make the inline line-buffered output stream
109  * code as compact as possible.
110  *
111  * _ub, _up, and _ur are used when ungetc() pushes back more characters
112  * than fit in the current _bf, or when ungetc() pushes back a character
113  * that does not match the previous one in _bf.  When this happens,
114  * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff
115  * _ub._base!=NULL) and _up and _ur save the current values of _p and _r.
116  *
117  * Certain members of __sFILE are accessed directly via macros or
118  * inline functions.  To preserve ABI compat, these members must not
119  * be disturbed.  These members are marked below with (*).
120  */
121 struct __sFILE {
122 	unsigned char *_p;	/* (*) current position in (some) buffer */
123 	int	_r;		/* (*) read space left for getc() */
124 	int	_w;		/* (*) write space left for putc() */
125 	short	_flags;		/* (*) flags, below; this FILE is free if 0 */
126 	short	_file;		/* (*) fileno, if Unix descriptor, else -1 */
127 	struct	__sbuf _bf;	/* (*) the buffer (at least 1 byte, if !NULL) */
128 	int	_lbfsize;	/* (*) 0 or -_bf._size, for inline putc */
129 
130 	/* operations */
131 	void	*_cookie;	/* (*) cookie passed to io functions */
132 	int	(* _Nullable _close)(void *);
133 	int	(* _Nullable _read)(void *, char *, int);
134 	fpos_t	(* _Nullable _seek)(void *, fpos_t, int);
135 	int	(* _Nullable _write)(void *, const char *, int);
136 
137 	/* separate buffer for long sequences of ungetc() */
138 	struct	__sbuf _ub;	/* ungetc buffer */
139 	unsigned char	*_up;	/* saved _p when _p is doing ungetc data */
140 	int	_ur;		/* saved _r when _r is counting ungetc data */
141 
142 	/* tricks to meet minimum requirements even when malloc() fails */
143 	unsigned char _ubuf[3];	/* guarantee an ungetc() buffer */
144 	unsigned char _nbuf[1];	/* guarantee a getc() buffer */
145 
146 	/* separate buffer for fgetln() when line crosses buffer boundary */
147 	struct	__sbuf _lb;	/* buffer for fgetln() */
148 
149 	/* Unix stdio files get aligned to block boundaries on fseek() */
150 	int	_blksize;	/* stat.st_blksize (may be != _bf._size) */
151 	fpos_t	_offset;	/* current lseek offset */
152 
153 	struct pthread_mutex *_fl_mutex;	/* used for MT-safety */
154 	struct pthread *_fl_owner;	/* current owner */
155 	int	_fl_count;	/* recursive lock count */
156 	int	_orientation;	/* orientation for fwide() */
157 	__mbstate_t _mbstate;	/* multibyte conversion state */
158 	int	_flags2;	/* additional flags */
159 };
160 #ifndef _STDFILE_DECLARED
161 #define _STDFILE_DECLARED
162 typedef struct __sFILE FILE;
163 #endif
164 #ifndef _STDSTREAM_DECLARED
165 __BEGIN_DECLS
166 extern FILE *__stdinp;
167 extern FILE *__stdoutp;
168 extern FILE *__stderrp;
169 __END_DECLS
170 #define	_STDSTREAM_DECLARED
171 #endif
172 
173 #define	__SLBF	0x0001		/* line buffered */
174 #define	__SNBF	0x0002		/* unbuffered */
175 #define	__SRD	0x0004		/* OK to read */
176 #define	__SWR	0x0008		/* OK to write */
177 	/* RD and WR are never simultaneously asserted */
178 #define	__SRW	0x0010		/* open for reading & writing */
179 #define	__SEOF	0x0020		/* found EOF */
180 #define	__SERR	0x0040		/* found error */
181 #define	__SMBF	0x0080		/* _bf._base is from malloc */
182 #define	__SAPP	0x0100		/* fdopen()ed in append mode */
183 #define	__SSTR	0x0200		/* this is an sprintf/snprintf string */
184 #define	__SOPT	0x0400		/* do fseek() optimization */
185 #define	__SNPT	0x0800		/* do not do fseek() optimization */
186 #define	__SOFF	0x1000		/* set iff _offset is in fact correct */
187 #define	__SMOD	0x2000		/* true => fgetln modified _p text */
188 #define	__SALC	0x4000		/* allocate string space dynamically */
189 #define	__SIGN	0x8000		/* ignore this file in _fwalk */
190 
191 #define	__S2OAP	0x0001		/* O_APPEND mode is set */
192 
193 /*
194  * The following three definitions are for ANSI C, which took them
195  * from System V, which brilliantly took internal interface macros and
196  * made them official arguments to setvbuf(), without renaming them.
197  * Hence, these ugly _IOxxx names are *supposed* to appear in user code.
198  *
199  * Although numbered as their counterparts above, the implementation
200  * does not rely on this.
201  */
202 #define	_IOFBF	0		/* setvbuf should set fully buffered */
203 #define	_IOLBF	1		/* setvbuf should set line buffered */
204 #define	_IONBF	2		/* setvbuf should set unbuffered */
205 
206 #define	BUFSIZ	1024		/* size of buffer used by setbuf */
207 #define	EOF	(-1)
208 
209 /*
210  * FOPEN_MAX is a minimum maximum, and is the number of streams that
211  * stdio can provide without attempting to allocate further resources
212  * (which could fail).  Do not use this for anything.
213  */
214 				/* must be == _POSIX_STREAM_MAX <limits.h> */
215 #ifndef FOPEN_MAX
216 #define	FOPEN_MAX	20	/* must be <= OPEN_MAX <sys/syslimits.h> */
217 #endif
218 #define	FILENAME_MAX	1024	/* must be <= PATH_MAX <sys/syslimits.h> */
219 
220 /* System V/ANSI C; this is the wrong way to do this, do *not* use these. */
221 #if __XSI_VISIBLE
222 #define	P_tmpdir	"/tmp/"
223 #endif
224 #define	L_tmpnam	1024	/* XXX must be == PATH_MAX */
225 #define	TMP_MAX		308915776
226 
227 #ifndef SEEK_SET
228 #define	SEEK_SET	0	/* set file offset to offset */
229 #endif
230 #ifndef SEEK_CUR
231 #define	SEEK_CUR	1	/* set file offset to current plus offset */
232 #endif
233 #ifndef SEEK_END
234 #define	SEEK_END	2	/* set file offset to EOF plus offset */
235 #endif
236 
237 #define	stdin	__stdinp
238 #define	stdout	__stdoutp
239 #define	stderr	__stderrp
240 
241 /*
242  * Functions defined in all versions of POSIX 1003.1.
243  */
244 #if __BSD_VISIBLE || (__POSIX_VISIBLE && __POSIX_VISIBLE <= 199506)
245 #define	L_cuserid	17	/* size for cuserid(3); MAXLOGNAME, legacy */
246 #endif
247 
248 #if __POSIX_VISIBLE
249 #define	L_ctermid	1024	/* size for ctermid(3); PATH_MAX */
250 #endif /* __POSIX_VISIBLE */
251 
252 #if !defined(_STANDALONE) && defined(_FORTIFY_SOURCE) && _FORTIFY_SOURCE > 0
253 #include <ssp/stdio.h>
254 #endif
255 
256 __BEGIN_DECLS
257 #ifdef _XLOCALE_H_
258 #include <xlocale/_stdio.h>
259 #endif
260 /*
261  * Functions defined in ANSI C standard.
262  */
263 void	 clearerr(FILE *);
264 int	 fclose(FILE *);
265 int	 feof(FILE *);
266 int	 ferror(FILE *);
267 int	 fflush(FILE *);
268 int	 fgetc(FILE *);
269 int	 fgetpos(FILE * __restrict, fpos_t * __restrict);
270 char	*(fgets)(char * __restrict, int, FILE * __restrict);
271 FILE	*fopen(const char * __restrict, const char * __restrict);
272 int	 fprintf(FILE * __restrict, const char * __restrict, ...);
273 int	 fputc(int, FILE *);
274 int	 fputs(const char * __restrict, FILE * __restrict);
275 size_t	 fread(void * __restrict, size_t, size_t, FILE * __restrict);
276 FILE	*freopen(const char * __restrict, const char * __restrict, FILE * __restrict);
277 int	 fscanf(FILE * __restrict, const char * __restrict, ...);
278 int	 fseek(FILE *, long, int);
279 int	 fsetpos(FILE *, const fpos_t *);
280 long	 ftell(FILE *);
281 size_t	 fwrite(const void * __restrict, size_t, size_t, FILE * __restrict);
282 int	 getc(FILE *);
283 int	 getchar(void);
284 #if __EXT1_VISIBLE
285 char	*gets_s(char *, rsize_t);
286 #endif
287 void	 perror(const char *);
288 int	 printf(const char * __restrict, ...);
289 int	 putc(int, FILE *);
290 int	 putchar(int);
291 int	 puts(const char *);
292 int	 remove(const char *);
293 int	 rename(const char *, const char *);
294 void	 rewind(FILE *);
295 int	 scanf(const char * __restrict, ...);
296 void	 setbuf(FILE * __restrict, char * __restrict);
297 int	 setvbuf(FILE * __restrict, char * __restrict, int, size_t);
298 int	 (sprintf)(char * __restrict, const char * __restrict, ...);
299 int	 sscanf(const char * __restrict, const char * __restrict, ...);
300 FILE	*tmpfile(void);
301 char	*tmpnam(char *);
302 int	 ungetc(int, FILE *);
303 int	 vfprintf(FILE * __restrict, const char * __restrict,
304 	    __va_list);
305 int	 vprintf(const char * __restrict, __va_list);
306 int	 (vsprintf)(char * __restrict, const char * __restrict,
307 	    __va_list);
308 
309 #if __ISO_C_VISIBLE >= 1999 || __POSIX_VISIBLE >= 199506
310 int	 (snprintf)(char * __restrict, size_t, const char * __restrict,
311 	    ...) __printflike(3, 4);
312 int	 (vsnprintf)(char * __restrict, size_t, const char * __restrict,
313 	    __va_list) __printflike(3, 0);
314 #endif
315 #if __ISO_C_VISIBLE >= 1999
316 int	 vfscanf(FILE * __restrict, const char * __restrict, __va_list)
317 	    __scanflike(2, 0);
318 int	 vscanf(const char * __restrict, __va_list) __scanflike(1, 0);
319 int	 vsscanf(const char * __restrict, const char * __restrict, __va_list)
320 	    __scanflike(2, 0);
321 #endif
322 
323 #if __POSIX_VISIBLE
324 char	*ctermid(char *);
325 FILE	*fdopen(int, const char *);
326 int	 fileno(FILE *);
327 #endif /* __POSIX_VISIBLE */
328 
329 #if __POSIX_VISIBLE >= 199209
330 int	 pclose(FILE *);
331 FILE	*popen(const char *, const char *);
332 #endif
333 
334 #if __POSIX_VISIBLE >= 199506
335 int	 ftrylockfile(FILE *);
336 void	 flockfile(FILE *);
337 void	 funlockfile(FILE *);
338 
339 /*
340  * These are normally used through macros as defined below, but POSIX
341  * requires functions as well.
342  */
343 int	 getc_unlocked(FILE *);
344 int	 getchar_unlocked(void);
345 int	 putc_unlocked(int, FILE *);
346 int	 putchar_unlocked(int);
347 #endif
348 #if __BSD_VISIBLE
349 void	 clearerr_unlocked(FILE *);
350 int	 feof_unlocked(FILE *);
351 int	 ferror_unlocked(FILE *);
352 int	 fflush_unlocked(FILE *);
353 int	 fileno_unlocked(FILE *);
354 int	 fputc_unlocked(int, FILE *);
355 int	 fputs_unlocked(const char * __restrict, FILE * __restrict);
356 size_t	 fread_unlocked(void * __restrict, size_t, size_t, FILE * __restrict);
357 size_t	 fwrite_unlocked(const void * __restrict, size_t, size_t,
358     FILE * __restrict);
359 #endif
360 
361 #if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE >= 500
362 int	 fseeko(FILE *, __off_t, int);
363 __off_t	 ftello(FILE *);
364 #endif
365 
366 #if __BSD_VISIBLE || __XSI_VISIBLE > 0 && __XSI_VISIBLE < 600
367 int	 getw(FILE *);
368 int	 putw(int, FILE *);
369 #endif /* BSD or X/Open before issue 6 */
370 
371 #if __XSI_VISIBLE
372 char	*tempnam(const char *, const char *);
373 #endif
374 
375 #if __POSIX_VISIBLE >= 200809
376 FILE	*fmemopen(void * __restrict, size_t, const char * __restrict);
377 ssize_t	 getdelim(char ** __restrict, size_t * __restrict, int,
378 	    FILE * __restrict);
379 FILE	*open_memstream(char **, size_t *);
380 int	 renameat(int, const char *, int, const char *);
381 int	 vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0);
382 /* _WITH_GETLINE to allow pre 11 sources to build on 11+ systems */
383 ssize_t	 getline(char ** __restrict, size_t * __restrict, FILE * __restrict);
384 int	 dprintf(int, const char * __restrict, ...) __printflike(2, 3);
385 #endif /* __POSIX_VISIBLE >= 200809 */
386 
387 /*
388  * Routines that are purely local.
389  */
390 #if __BSD_VISIBLE
391 int	 asprintf(char **, const char *, ...) __printflike(2, 3);
392 char	*ctermid_r(char *);
393 void	 fcloseall(void);
394 int	 fdclose(FILE *, int *);
395 char	*fgetln(FILE *, size_t *);
396 const char *fmtcheck(const char *, const char *) __format_arg(2);
397 int	 fpurge(FILE *);
398 void	 setbuffer(FILE *, char *, int);
399 int	 setlinebuf(FILE *);
400 int	 vasprintf(char **, const char *, __va_list)
401 	    __printflike(2, 0);
402 
403 /*
404  * The system error table contains messages for the first sys_nerr
405  * positive errno values.  Use strerror() or strerror_r() from <string.h>
406  * instead.
407  */
408 extern const int sys_nerr;
409 extern const char * const sys_errlist[];
410 
411 /*
412  * Stdio function-access interface.
413  */
414 FILE	*funopen(const void *,
415 	    int (* _Nullable)(void *, char *, int),
416 	    int (* _Nullable)(void *, const char *, int),
417 	    fpos_t (* _Nullable)(void *, fpos_t, int),
418 	    int (* _Nullable)(void *));
419 #define	fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0)
420 #define	fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0)
421 
422 #if __BSD_VISIBLE
423 typedef __ssize_t cookie_read_function_t(void *, char *, size_t);
424 typedef __ssize_t cookie_write_function_t(void *, const char *, size_t);
425 typedef int cookie_seek_function_t(void *, off64_t *, int);
426 typedef int cookie_close_function_t(void *);
427 typedef struct {
428 	cookie_read_function_t	*read;
429 	cookie_write_function_t	*write;
430 	cookie_seek_function_t	*seek;
431 	cookie_close_function_t	*close;
432 } cookie_io_functions_t;
433 FILE	*fopencookie(void *, const char *, cookie_io_functions_t);
434 #endif
435 
436 /*
437  * Portability hacks.  See <sys/types.h>.
438  */
439 #ifndef _FTRUNCATE_DECLARED
440 #define	_FTRUNCATE_DECLARED
441 int	 ftruncate(int, __off_t);
442 #endif
443 #ifndef _LSEEK_DECLARED
444 #define	_LSEEK_DECLARED
445 __off_t	 lseek(int, __off_t, int);
446 #endif
447 #ifndef _MMAP_DECLARED
448 #define	_MMAP_DECLARED
449 void	*mmap(void *, size_t, int, int, int, __off_t);
450 #endif
451 #ifndef _TRUNCATE_DECLARED
452 #define	_TRUNCATE_DECLARED
453 int	 truncate(const char *, __off_t);
454 #endif
455 #endif /* __BSD_VISIBLE */
456 
457 /*
458  * Functions internal to the implementation.
459  */
460 int	__srget(FILE *);
461 int	__swbuf(int, FILE *);
462 
463 /*
464  * The __sfoo macros are here so that we can
465  * define function versions in the C library.
466  */
467 #define	__sgetc(p) (--(p)->_r < 0 ? __srget(p) : (int)(*(p)->_p++))
468 #if defined(__GNUC__) && defined(__STDC__)
469 static __inline int __sputc(int _c, FILE *_p) {
470 	if (--_p->_w >= 0 || (_p->_w >= _p->_lbfsize && (char)_c != '\n'))
471 		return (*_p->_p++ = _c);
472 	else
473 		return (__swbuf(_c, _p));
474 }
475 #else
476 /*
477  * This has been tuned to generate reasonable code on the vax using pcc.
478  */
479 #define	__sputc(c, p) \
480 	(--(p)->_w < 0 ? \
481 		(p)->_w >= (p)->_lbfsize ? \
482 			(*(p)->_p = (c)), *(p)->_p != '\n' ? \
483 				(int)*(p)->_p++ : \
484 				__swbuf('\n', p) : \
485 			__swbuf((int)(c), p) : \
486 		(*(p)->_p = (c), (int)*(p)->_p++))
487 #endif
488 
489 #ifndef __LIBC_ISTHREADED_DECLARED
490 #define __LIBC_ISTHREADED_DECLARED
491 extern int __isthreaded;
492 #endif
493 
494 #ifndef __cplusplus
495 
496 #define	__sfeof(p)	(((p)->_flags & __SEOF) != 0)
497 #define	__sferror(p)	(((p)->_flags & __SERR) != 0)
498 #define	__sclearerr(p)	((void)((p)->_flags &= ~(__SERR|__SEOF)))
499 #define	__sfileno(p)	((p)->_file)
500 
501 
502 #define	feof(p)		(!__isthreaded ? __sfeof(p) : (feof)(p))
503 #define	ferror(p)	(!__isthreaded ? __sferror(p) : (ferror)(p))
504 #define	clearerr(p)	(!__isthreaded ? __sclearerr(p) : (clearerr)(p))
505 
506 #if __POSIX_VISIBLE
507 #define	fileno(p)	(!__isthreaded ? __sfileno(p) : (fileno)(p))
508 #endif
509 
510 #define	getc(fp)	(!__isthreaded ? __sgetc(fp) : (getc)(fp))
511 #define	putc(x, fp)	(!__isthreaded ? __sputc(x, fp) : (putc)(x, fp))
512 
513 #define	getchar()	getc(stdin)
514 #define	putchar(x)	putc(x, stdout)
515 
516 #if __BSD_VISIBLE
517 /*
518  * See ISO/IEC 9945-1 ANSI/IEEE Std 1003.1 Second Edition 1996-07-12
519  * B.8.2.7 for the rationale behind the *_unlocked() macros.
520  */
521 #define	clearerr_unlocked(p)	__sclearerr(p)
522 #define	feof_unlocked(p)	__sfeof(p)
523 #define	ferror_unlocked(p)	__sferror(p)
524 #define	fileno_unlocked(p)	__sfileno(p)
525 #define	fputc_unlocked(s, p)	__sputc(s, p)
526 #endif
527 #if __POSIX_VISIBLE >= 199506
528 #define	getc_unlocked(fp)	__sgetc(fp)
529 #define	putc_unlocked(x, fp)	__sputc(x, fp)
530 
531 #define	getchar_unlocked()	getc_unlocked(stdin)
532 #define	putchar_unlocked(x)	putc_unlocked(x, stdout)
533 #endif
534 #endif /* __cplusplus */
535 
536 __END_DECLS
537 __NULLABILITY_PRAGMA_POP
538 
539 #endif /* !_STDIO_H_ */
540