xref: /freebsd/include/stdio.h (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
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  *	@(#)stdio.h	8.5 (Berkeley) 4/29/95
35  * $FreeBSD$
36  */
37 
38 #ifndef	_STDIO_H_
39 #define	_STDIO_H_
40 
41 #include <sys/cdefs.h>
42 #include <sys/_null.h>
43 #include <sys/_types.h>
44 
45 __NULLABILITY_PRAGMA_PUSH
46 
47 typedef	__off_t		fpos_t;
48 
49 #ifndef _SIZE_T_DECLARED
50 typedef	__size_t	size_t;
51 #define	_SIZE_T_DECLARED
52 #endif
53 
54 #if __POSIX_VISIBLE >= 200809
55 #ifndef _OFF_T_DECLARED
56 #define	_OFF_T_DECLARED
57 typedef	__off_t		off_t;
58 #endif
59 #ifndef _SSIZE_T_DECLARED
60 #define	_SSIZE_T_DECLARED
61 typedef	__ssize_t	ssize_t;
62 #endif
63 #endif
64 
65 #ifndef _OFF64_T_DECLARED
66 #define	_OFF64_T_DECLARED
67 typedef	__off64_t	off64_t;
68 #endif
69 
70 #if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE
71 #ifndef _VA_LIST_DECLARED
72 typedef	__va_list	va_list;
73 #define	_VA_LIST_DECLARED
74 #endif
75 #endif
76 
77 #define	_FSTDIO			/* Define for new stdio with functions. */
78 
79 /*
80  * NB: to fit things in six character monocase externals, the stdio
81  * code uses the prefix `__s' for stdio objects, typically followed
82  * by a three-character attempt at a mnemonic.
83  */
84 
85 /* stdio buffers */
86 struct __sbuf {
87 	unsigned char *_base;
88 	int	_size;
89 };
90 
91 /*
92  * stdio state variables.
93  *
94  * The following always hold:
95  *
96  *	if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR),
97  *		_lbfsize is -_bf._size, else _lbfsize is 0
98  *	if _flags&__SRD, _w is 0
99  *	if _flags&__SWR, _r is 0
100  *
101  * This ensures that the getc and putc macros (or inline functions) never
102  * try to write or read from a file that is in `read' or `write' mode.
103  * (Moreover, they can, and do, automatically switch from read mode to
104  * write mode, and back, on "r+" and "w+" files.)
105  *
106  * _lbfsize is used only to make the inline line-buffered output stream
107  * code as compact as possible.
108  *
109  * _ub, _up, and _ur are used when ungetc() pushes back more characters
110  * than fit in the current _bf, or when ungetc() pushes back a character
111  * that does not match the previous one in _bf.  When this happens,
112  * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff
113  * _ub._base!=NULL) and _up and _ur save the current values of _p and _r.
114  *
115  * Certain members of __sFILE are accessed directly via macros or
116  * inline functions.  To preserve ABI compat, these members must not
117  * be disturbed.  These members are marked below with (*).
118  */
119 struct __sFILE {
120 	unsigned char *_p;	/* (*) current position in (some) buffer */
121 	int	_r;		/* (*) read space left for getc() */
122 	int	_w;		/* (*) write space left for putc() */
123 	short	_flags;		/* (*) flags, below; this FILE is free if 0 */
124 	short	_file;		/* (*) fileno, if Unix descriptor, else -1 */
125 	struct	__sbuf _bf;	/* (*) the buffer (at least 1 byte, if !NULL) */
126 	int	_lbfsize;	/* (*) 0 or -_bf._size, for inline putc */
127 
128 	/* operations */
129 	void	*_cookie;	/* (*) cookie passed to io functions */
130 	int	(* _Nullable _close)(void *);
131 	int	(* _Nullable _read)(void *, char *, int);
132 	fpos_t	(* _Nullable _seek)(void *, fpos_t, int);
133 	int	(* _Nullable _write)(void *, const char *, int);
134 
135 	/* separate buffer for long sequences of ungetc() */
136 	struct	__sbuf _ub;	/* ungetc buffer */
137 	unsigned char	*_up;	/* saved _p when _p is doing ungetc data */
138 	int	_ur;		/* saved _r when _r is counting ungetc data */
139 
140 	/* tricks to meet minimum requirements even when malloc() fails */
141 	unsigned char _ubuf[3];	/* guarantee an ungetc() buffer */
142 	unsigned char _nbuf[1];	/* guarantee a getc() buffer */
143 
144 	/* separate buffer for fgetln() when line crosses buffer boundary */
145 	struct	__sbuf _lb;	/* buffer for fgetln() */
146 
147 	/* Unix stdio files get aligned to block boundaries on fseek() */
148 	int	_blksize;	/* stat.st_blksize (may be != _bf._size) */
149 	fpos_t	_offset;	/* current lseek offset */
150 
151 	struct pthread_mutex *_fl_mutex;	/* used for MT-safety */
152 	struct pthread *_fl_owner;	/* current owner */
153 	int	_fl_count;	/* recursive lock count */
154 	int	_orientation;	/* orientation for fwide() */
155 	__mbstate_t _mbstate;	/* multibyte conversion state */
156 	int	_flags2;	/* additional flags */
157 };
158 #ifndef _STDFILE_DECLARED
159 #define _STDFILE_DECLARED
160 typedef struct __sFILE FILE;
161 #endif
162 #ifndef _STDSTREAM_DECLARED
163 __BEGIN_DECLS
164 extern FILE *__stdinp;
165 extern FILE *__stdoutp;
166 extern FILE *__stderrp;
167 __END_DECLS
168 #define	_STDSTREAM_DECLARED
169 #endif
170 
171 #define	__SLBF	0x0001		/* line buffered */
172 #define	__SNBF	0x0002		/* unbuffered */
173 #define	__SRD	0x0004		/* OK to read */
174 #define	__SWR	0x0008		/* OK to write */
175 	/* RD and WR are never simultaneously asserted */
176 #define	__SRW	0x0010		/* open for reading & writing */
177 #define	__SEOF	0x0020		/* found EOF */
178 #define	__SERR	0x0040		/* found error */
179 #define	__SMBF	0x0080		/* _bf._base is from malloc */
180 #define	__SAPP	0x0100		/* fdopen()ed in append mode */
181 #define	__SSTR	0x0200		/* this is an sprintf/snprintf string */
182 #define	__SOPT	0x0400		/* do fseek() optimization */
183 #define	__SNPT	0x0800		/* do not do fseek() optimization */
184 #define	__SOFF	0x1000		/* set iff _offset is in fact correct */
185 #define	__SMOD	0x2000		/* true => fgetln modified _p text */
186 #define	__SALC	0x4000		/* allocate string space dynamically */
187 #define	__SIGN	0x8000		/* ignore this file in _fwalk */
188 
189 #define	__S2OAP	0x0001		/* O_APPEND mode is set */
190 
191 /*
192  * The following three definitions are for ANSI C, which took them
193  * from System V, which brilliantly took internal interface macros and
194  * made them official arguments to setvbuf(), without renaming them.
195  * Hence, these ugly _IOxxx names are *supposed* to appear in user code.
196  *
197  * Although numbered as their counterparts above, the implementation
198  * does not rely on this.
199  */
200 #define	_IOFBF	0		/* setvbuf should set fully buffered */
201 #define	_IOLBF	1		/* setvbuf should set line buffered */
202 #define	_IONBF	2		/* setvbuf should set unbuffered */
203 
204 #define	BUFSIZ	1024		/* size of buffer used by setbuf */
205 #define	EOF	(-1)
206 
207 /*
208  * FOPEN_MAX is a minimum maximum, and is the number of streams that
209  * stdio can provide without attempting to allocate further resources
210  * (which could fail).  Do not use this for anything.
211  */
212 				/* must be == _POSIX_STREAM_MAX <limits.h> */
213 #ifndef FOPEN_MAX
214 #define	FOPEN_MAX	20	/* must be <= OPEN_MAX <sys/syslimits.h> */
215 #endif
216 #define	FILENAME_MAX	1024	/* must be <= PATH_MAX <sys/syslimits.h> */
217 
218 /* System V/ANSI C; this is the wrong way to do this, do *not* use these. */
219 #if __XSI_VISIBLE
220 #define	P_tmpdir	"/tmp/"
221 #endif
222 #define	L_tmpnam	1024	/* XXX must be == PATH_MAX */
223 #define	TMP_MAX		308915776
224 
225 #ifndef SEEK_SET
226 #define	SEEK_SET	0	/* set file offset to offset */
227 #endif
228 #ifndef SEEK_CUR
229 #define	SEEK_CUR	1	/* set file offset to current plus offset */
230 #endif
231 #ifndef SEEK_END
232 #define	SEEK_END	2	/* set file offset to EOF plus offset */
233 #endif
234 
235 #define	stdin	__stdinp
236 #define	stdout	__stdoutp
237 #define	stderr	__stderrp
238 
239 __BEGIN_DECLS
240 #ifdef _XLOCALE_H_
241 #include <xlocale/_stdio.h>
242 #endif
243 /*
244  * Functions defined in ANSI C standard.
245  */
246 void	 clearerr(FILE *);
247 int	 fclose(FILE *);
248 int	 feof(FILE *);
249 int	 ferror(FILE *);
250 int	 fflush(FILE *);
251 int	 fgetc(FILE *);
252 int	 fgetpos(FILE * __restrict, fpos_t * __restrict);
253 char	*fgets(char * __restrict, int, FILE * __restrict);
254 FILE	*fopen(const char * __restrict, const char * __restrict);
255 int	 fprintf(FILE * __restrict, const char * __restrict, ...);
256 int	 fputc(int, FILE *);
257 int	 fputs(const char * __restrict, FILE * __restrict);
258 size_t	 fread(void * __restrict, size_t, size_t, FILE * __restrict);
259 FILE	*freopen(const char * __restrict, const char * __restrict, FILE * __restrict);
260 int	 fscanf(FILE * __restrict, const char * __restrict, ...);
261 int	 fseek(FILE *, long, int);
262 int	 fsetpos(FILE *, const fpos_t *);
263 long	 ftell(FILE *);
264 size_t	 fwrite(const void * __restrict, size_t, size_t, FILE * __restrict);
265 int	 getc(FILE *);
266 int	 getchar(void);
267 char	*gets(char *);
268 void	 perror(const char *);
269 int	 printf(const char * __restrict, ...);
270 int	 putc(int, FILE *);
271 int	 putchar(int);
272 int	 puts(const char *);
273 int	 remove(const char *);
274 int	 rename(const char *, const char *);
275 void	 rewind(FILE *);
276 int	 scanf(const char * __restrict, ...);
277 void	 setbuf(FILE * __restrict, char * __restrict);
278 int	 setvbuf(FILE * __restrict, char * __restrict, int, size_t);
279 int	 sprintf(char * __restrict, const char * __restrict, ...);
280 int	 sscanf(const char * __restrict, const char * __restrict, ...);
281 FILE	*tmpfile(void);
282 char	*tmpnam(char *);
283 int	 ungetc(int, FILE *);
284 int	 vfprintf(FILE * __restrict, const char * __restrict,
285 	    __va_list);
286 int	 vprintf(const char * __restrict, __va_list);
287 int	 vsprintf(char * __restrict, const char * __restrict,
288 	    __va_list);
289 
290 #if __ISO_C_VISIBLE >= 1999
291 int	 snprintf(char * __restrict, size_t, const char * __restrict,
292 	    ...) __printflike(3, 4);
293 int	 vfscanf(FILE * __restrict, const char * __restrict, __va_list)
294 	    __scanflike(2, 0);
295 int	 vscanf(const char * __restrict, __va_list) __scanflike(1, 0);
296 int	 vsnprintf(char * __restrict, size_t, const char * __restrict,
297 	    __va_list) __printflike(3, 0);
298 int	 vsscanf(const char * __restrict, const char * __restrict, __va_list)
299 	    __scanflike(2, 0);
300 #endif
301 
302 /*
303  * Functions defined in all versions of POSIX 1003.1.
304  */
305 #if __BSD_VISIBLE || (__POSIX_VISIBLE && __POSIX_VISIBLE <= 199506)
306 #define	L_cuserid	17	/* size for cuserid(3); MAXLOGNAME, legacy */
307 #endif
308 
309 #if __POSIX_VISIBLE
310 #define	L_ctermid	1024	/* size for ctermid(3); PATH_MAX */
311 
312 char	*ctermid(char *);
313 FILE	*fdopen(int, const char *);
314 int	 fileno(FILE *);
315 #endif /* __POSIX_VISIBLE */
316 
317 #if __POSIX_VISIBLE >= 199209
318 int	 pclose(FILE *);
319 FILE	*popen(const char *, const char *);
320 #endif
321 
322 #if __POSIX_VISIBLE >= 199506
323 int	 ftrylockfile(FILE *);
324 void	 flockfile(FILE *);
325 void	 funlockfile(FILE *);
326 
327 /*
328  * These are normally used through macros as defined below, but POSIX
329  * requires functions as well.
330  */
331 int	 getc_unlocked(FILE *);
332 int	 getchar_unlocked(void);
333 int	 putc_unlocked(int, FILE *);
334 int	 putchar_unlocked(int);
335 #endif
336 #if __BSD_VISIBLE
337 void	 clearerr_unlocked(FILE *);
338 int	 feof_unlocked(FILE *);
339 int	 ferror_unlocked(FILE *);
340 int	 fileno_unlocked(FILE *);
341 #endif
342 
343 #if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE >= 500
344 int	 fseeko(FILE *, __off_t, int);
345 __off_t	 ftello(FILE *);
346 #endif
347 
348 #if __BSD_VISIBLE || __XSI_VISIBLE > 0 && __XSI_VISIBLE < 600
349 int	 getw(FILE *);
350 int	 putw(int, FILE *);
351 #endif /* BSD or X/Open before issue 6 */
352 
353 #if __XSI_VISIBLE
354 char	*tempnam(const char *, const char *);
355 #endif
356 
357 #if __POSIX_VISIBLE >= 200809
358 FILE	*fmemopen(void * __restrict, size_t, const char * __restrict);
359 ssize_t	 getdelim(char ** __restrict, size_t * __restrict, int,
360 	    FILE * __restrict);
361 FILE	*open_memstream(char **, size_t *);
362 int	 renameat(int, const char *, int, const char *);
363 int	 vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0);
364 /* _WITH_GETLINE to allow pre 11 sources to build on 11+ systems */
365 ssize_t	 getline(char ** __restrict, size_t * __restrict, FILE * __restrict);
366 int	 dprintf(int, const char * __restrict, ...) __printflike(2, 3);
367 #endif /* __POSIX_VISIBLE >= 200809 */
368 
369 /*
370  * Routines that are purely local.
371  */
372 #if __BSD_VISIBLE
373 int	 asprintf(char **, const char *, ...) __printflike(2, 3);
374 char	*ctermid_r(char *);
375 void	 fcloseall(void);
376 int	 fdclose(FILE *, int *);
377 char	*fgetln(FILE *, size_t *);
378 const char *fmtcheck(const char *, const char *) __format_arg(2);
379 int	 fpurge(FILE *);
380 void	 setbuffer(FILE *, char *, int);
381 int	 setlinebuf(FILE *);
382 int	 vasprintf(char **, const char *, __va_list)
383 	    __printflike(2, 0);
384 
385 /*
386  * The system error table contains messages for the first sys_nerr
387  * positive errno values.  Use strerror() or strerror_r() from <string.h>
388  * instead.
389  */
390 extern const int sys_nerr;
391 extern const char * const sys_errlist[];
392 
393 /*
394  * Stdio function-access interface.
395  */
396 FILE	*funopen(const void *,
397 	    int (* _Nullable)(void *, char *, int),
398 	    int (* _Nullable)(void *, const char *, int),
399 	    fpos_t (* _Nullable)(void *, fpos_t, int),
400 	    int (* _Nullable)(void *));
401 #define	fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0)
402 #define	fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0)
403 
404 typedef __ssize_t cookie_read_function_t(void *, char *, size_t);
405 typedef __ssize_t cookie_write_function_t(void *, const char *, size_t);
406 typedef int cookie_seek_function_t(void *, off64_t *, int);
407 typedef int cookie_close_function_t(void *);
408 typedef struct {
409 	cookie_read_function_t	*read;
410 	cookie_write_function_t	*write;
411 	cookie_seek_function_t	*seek;
412 	cookie_close_function_t	*close;
413 } cookie_io_functions_t;
414 FILE	*fopencookie(void *, const char *, cookie_io_functions_t);
415 
416 /*
417  * Portability hacks.  See <sys/types.h>.
418  */
419 #ifndef _FTRUNCATE_DECLARED
420 #define	_FTRUNCATE_DECLARED
421 int	 ftruncate(int, __off_t);
422 #endif
423 #ifndef _LSEEK_DECLARED
424 #define	_LSEEK_DECLARED
425 __off_t	 lseek(int, __off_t, int);
426 #endif
427 #ifndef _MMAP_DECLARED
428 #define	_MMAP_DECLARED
429 void	*mmap(void *, size_t, int, int, int, __off_t);
430 #endif
431 #ifndef _TRUNCATE_DECLARED
432 #define	_TRUNCATE_DECLARED
433 int	 truncate(const char *, __off_t);
434 #endif
435 #endif /* __BSD_VISIBLE */
436 
437 /*
438  * Functions internal to the implementation.
439  */
440 int	__srget(FILE *);
441 int	__swbuf(int, FILE *);
442 
443 /*
444  * The __sfoo macros are here so that we can
445  * define function versions in the C library.
446  */
447 #define	__sgetc(p) (--(p)->_r < 0 ? __srget(p) : (int)(*(p)->_p++))
448 #if defined(__GNUC__) && defined(__STDC__)
449 static __inline int __sputc(int _c, FILE *_p) {
450 	if (--_p->_w >= 0 || (_p->_w >= _p->_lbfsize && (char)_c != '\n'))
451 		return (*_p->_p++ = _c);
452 	else
453 		return (__swbuf(_c, _p));
454 }
455 #else
456 /*
457  * This has been tuned to generate reasonable code on the vax using pcc.
458  */
459 #define	__sputc(c, p) \
460 	(--(p)->_w < 0 ? \
461 		(p)->_w >= (p)->_lbfsize ? \
462 			(*(p)->_p = (c)), *(p)->_p != '\n' ? \
463 				(int)*(p)->_p++ : \
464 				__swbuf('\n', p) : \
465 			__swbuf((int)(c), p) : \
466 		(*(p)->_p = (c), (int)*(p)->_p++))
467 #endif
468 
469 #ifndef __LIBC_ISTHREADED_DECLARED
470 #define __LIBC_ISTHREADED_DECLARED
471 extern int __isthreaded;
472 #endif
473 
474 #ifndef __cplusplus
475 
476 #define	__sfeof(p)	(((p)->_flags & __SEOF) != 0)
477 #define	__sferror(p)	(((p)->_flags & __SERR) != 0)
478 #define	__sclearerr(p)	((void)((p)->_flags &= ~(__SERR|__SEOF)))
479 #define	__sfileno(p)	((p)->_file)
480 
481 
482 #define	feof(p)		(!__isthreaded ? __sfeof(p) : (feof)(p))
483 #define	ferror(p)	(!__isthreaded ? __sferror(p) : (ferror)(p))
484 #define	clearerr(p)	(!__isthreaded ? __sclearerr(p) : (clearerr)(p))
485 
486 #if __POSIX_VISIBLE
487 #define	fileno(p)	(!__isthreaded ? __sfileno(p) : (fileno)(p))
488 #endif
489 
490 #define	getc(fp)	(!__isthreaded ? __sgetc(fp) : (getc)(fp))
491 #define	putc(x, fp)	(!__isthreaded ? __sputc(x, fp) : (putc)(x, fp))
492 
493 #define	getchar()	getc(stdin)
494 #define	putchar(x)	putc(x, stdout)
495 
496 #if __BSD_VISIBLE
497 /*
498  * See ISO/IEC 9945-1 ANSI/IEEE Std 1003.1 Second Edition 1996-07-12
499  * B.8.2.7 for the rationale behind the *_unlocked() macros.
500  */
501 #define	feof_unlocked(p)	__sfeof(p)
502 #define	ferror_unlocked(p)	__sferror(p)
503 #define	clearerr_unlocked(p)	__sclearerr(p)
504 #define	fileno_unlocked(p)	__sfileno(p)
505 #endif
506 #if __POSIX_VISIBLE >= 199506
507 #define	getc_unlocked(fp)	__sgetc(fp)
508 #define	putc_unlocked(x, fp)	__sputc(x, fp)
509 
510 #define	getchar_unlocked()	getc_unlocked(stdin)
511 #define	putchar_unlocked(x)	putc_unlocked(x, stdout)
512 #endif
513 #endif /* __cplusplus */
514 
515 __END_DECLS
516 __NULLABILITY_PRAGMA_POP
517 
518 #endif /* !_STDIO_H_ */
519