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1 /*	$OpenBSD: stdio.h,v 1.35 2006/01/13 18:10:09 miod Exp $	*/
2 /*	$NetBSD: stdio.h,v 1.18 1996/04/25 18:29:21 jtc Exp $	*/
3 
4 /*-
5  * Copyright (c) 1990 The Regents of the University of California.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Chris Torek.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)stdio.h	5.17 (Berkeley) 6/3/91
36  */
37 
38 #ifndef	_STDIO_H_
39 #define	_STDIO_H_
40 
41 #include <sys/cdefs.h>
42 #include <sys/types.h>
43 
44 #include <stdarg.h>
45 #include <stddef.h>
46 
47 #define __need_NULL
48 #include <stddef.h>
49 
50 __BEGIN_DECLS
51 
52 #define	_FSTDIO			/* Define for new stdio with functions. */
53 
54 typedef off_t fpos_t;		/* stdio file position type */
55 
56 /*
57  * NB: to fit things in six character monocase externals, the stdio
58  * code uses the prefix `__s' for stdio objects, typically followed
59  * by a three-character attempt at a mnemonic.
60  */
61 
62 /* stdio buffers */
63 #if defined(__LP64__)
64 struct __sbuf {
65   unsigned char* _base;
66   size_t _size;
67 };
68 #else
69 struct __sbuf {
70 	unsigned char *_base;
71 	int	_size;
72 };
73 #endif
74 
75 /*
76  * stdio state variables.
77  *
78  * The following always hold:
79  *
80  *	if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR),
81  *		_lbfsize is -_bf._size, else _lbfsize is 0
82  *	if _flags&__SRD, _w is 0
83  *	if _flags&__SWR, _r is 0
84  *
85  * This ensures that the getc and putc macros (or inline functions) never
86  * try to write or read from a file that is in `read' or `write' mode.
87  * (Moreover, they can, and do, automatically switch from read mode to
88  * write mode, and back, on "r+" and "w+" files.)
89  *
90  * _lbfsize is used only to make the inline line-buffered output stream
91  * code as compact as possible.
92  *
93  * _ub, _up, and _ur are used when ungetc() pushes back more characters
94  * than fit in the current _bf, or when ungetc() pushes back a character
95  * that does not match the previous one in _bf.  When this happens,
96  * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff
97  * _ub._base!=NULL) and _up and _ur save the current values of _p and _r.
98  *
99  * NOTE: if you change this structure, you also need to update the
100  * std() initializer in findfp.c.
101  */
102 typedef	struct __sFILE {
103 	unsigned char *_p;	/* current position in (some) buffer */
104 	int	_r;		/* read space left for getc() */
105 	int	_w;		/* write space left for putc() */
106 #if defined(__LP64__)
107 	int	_flags;		/* flags, below; this FILE is free if 0 */
108 	int	_file;		/* fileno, if Unix descriptor, else -1 */
109 #else
110 	short	_flags;		/* flags, below; this FILE is free if 0 */
111 	short	_file;		/* fileno, if Unix descriptor, else -1 */
112 #endif
113 	struct	__sbuf _bf;	/* the buffer (at least 1 byte, if !NULL) */
114 	int	_lbfsize;	/* 0 or -_bf._size, for inline putc */
115 
116 	/* operations */
117 	void	*_cookie;	/* cookie passed to io functions */
118 	int	(*_close)(void *);
119 	int	(*_read)(void *, char *, int);
120 	fpos_t	(*_seek)(void *, fpos_t, int);
121 	int	(*_write)(void *, const char *, int);
122 
123 	/* extension data, to avoid further ABI breakage */
124 	struct	__sbuf _ext;
125 	/* data for long sequences of ungetc() */
126 	unsigned char *_up;	/* saved _p when _p is doing ungetc data */
127 	int	_ur;		/* saved _r when _r is counting ungetc data */
128 
129 	/* tricks to meet minimum requirements even when malloc() fails */
130 	unsigned char _ubuf[3];	/* guarantee an ungetc() buffer */
131 	unsigned char _nbuf[1];	/* guarantee a getc() buffer */
132 
133 	/* separate buffer for fgetln() when line crosses buffer boundary */
134 	struct	__sbuf _lb;	/* buffer for fgetln() */
135 
136 	/* Unix stdio files get aligned to block boundaries on fseek() */
137 	int	_blksize;	/* stat.st_blksize (may be != _bf._size) */
138 	fpos_t	_offset;	/* current lseek offset */
139 } FILE;
140 
141 extern FILE __sF[];
142 
143 #define	__SLBF	0x0001		/* line buffered */
144 #define	__SNBF	0x0002		/* unbuffered */
145 #define	__SRD	0x0004		/* OK to read */
146 #define	__SWR	0x0008		/* OK to write */
147 	/* RD and WR are never simultaneously asserted */
148 #define	__SRW	0x0010		/* open for reading & writing */
149 #define	__SEOF	0x0020		/* found EOF */
150 #define	__SERR	0x0040		/* found error */
151 #define	__SMBF	0x0080		/* _buf is from malloc */
152 #define	__SAPP	0x0100		/* fdopen()ed in append mode */
153 #define	__SSTR	0x0200		/* this is an sprintf/snprintf string */
154 #define	__SOPT	0x0400		/* do fseek() optimization */
155 #define	__SNPT	0x0800		/* do not do fseek() optimization */
156 #define	__SOFF	0x1000		/* set iff _offset is in fact correct */
157 #define	__SMOD	0x2000		/* true => fgetln modified _p text */
158 #define	__SALC	0x4000		/* allocate string space dynamically */
159 #define	__SIGN	0x8000		/* ignore this file in _fwalk */
160 
161 /*
162  * The following three definitions are for ANSI C, which took them
163  * from System V, which brilliantly took internal interface macros and
164  * made them official arguments to setvbuf(), without renaming them.
165  * Hence, these ugly _IOxxx names are *supposed* to appear in user code.
166  *
167  * Although numbered as their counterparts above, the implementation
168  * does not rely on this.
169  */
170 #define	_IOFBF	0		/* setvbuf should set fully buffered */
171 #define	_IOLBF	1		/* setvbuf should set line buffered */
172 #define	_IONBF	2		/* setvbuf should set unbuffered */
173 
174 #define	BUFSIZ	1024		/* size of buffer used by setbuf */
175 #define	EOF	(-1)
176 
177 /*
178  * FOPEN_MAX is a minimum maximum, and is the number of streams that
179  * stdio can provide without attempting to allocate further resources
180  * (which could fail).  Do not use this for anything.
181  */
182 
183 #define	FOPEN_MAX	20	/* must be <= OPEN_MAX <sys/syslimits.h> */
184 #define	FILENAME_MAX	1024	/* must be <= PATH_MAX <sys/syslimits.h> */
185 
186 /* System V/ANSI C; this is the wrong way to do this, do *not* use these. */
187 #if __BSD_VISIBLE || __XPG_VISIBLE
188 #define	P_tmpdir	"/tmp/"
189 #endif
190 #define	L_tmpnam	1024	/* XXX must be == PATH_MAX */
191 #define	TMP_MAX		308915776
192 
193 /* Always ensure that these are consistent with <fcntl.h> and <unistd.h>! */
194 #ifndef SEEK_SET
195 #define	SEEK_SET	0	/* set file offset to offset */
196 #endif
197 #ifndef SEEK_CUR
198 #define	SEEK_CUR	1	/* set file offset to current plus offset */
199 #endif
200 #ifndef SEEK_END
201 #define	SEEK_END	2	/* set file offset to EOF plus offset */
202 #endif
203 
204 #define	stdin	(&__sF[0])
205 #define	stdout	(&__sF[1])
206 #define	stderr	(&__sF[2])
207 
208 /*
209  * Functions defined in ANSI C standard.
210  */
211 void	 clearerr(FILE *);
212 int	 fclose(FILE *);
213 int	 feof(FILE *);
214 int	 ferror(FILE *);
215 int	 fflush(FILE *);
216 int	 fgetc(FILE *);
217 char	*fgets(char * __restrict, int, FILE * __restrict);
218 FILE	*fopen(const char * __restrict , const char * __restrict);
219 int	 fprintf(FILE * __restrict , const char * __restrict, ...)
220 		__printflike(2, 3);
221 int	 fputc(int, FILE *);
222 int	 fputs(const char * __restrict, FILE * __restrict);
223 size_t	 fread(void * __restrict, size_t, size_t, FILE * __restrict);
224 FILE	*freopen(const char * __restrict, const char * __restrict,
225 	    FILE * __restrict);
226 int	 fscanf(FILE * __restrict, const char * __restrict, ...)
227 		__scanflike(2, 3);
228 int	 fseek(FILE *, long, int);
229 long	 ftell(FILE *);
230 size_t	 fwrite(const void * __restrict, size_t, size_t, FILE * __restrict);
231 int	 getc(FILE *);
232 int	 getchar(void);
233 ssize_t	 getdelim(char ** __restrict, size_t * __restrict, int,
234 	    FILE * __restrict);
235 ssize_t	 getline(char ** __restrict, size_t * __restrict, FILE * __restrict);
236 
237 void	 perror(const char *);
238 int	 printf(const char * __restrict, ...)
239 		__printflike(1, 2);
240 int	 putc(int, FILE *);
241 int	 putchar(int);
242 int	 puts(const char *);
243 int	 remove(const char *);
244 void	 rewind(FILE *);
245 int	 scanf(const char * __restrict, ...)
246 		__scanflike(1, 2);
247 void	 setbuf(FILE * __restrict, char * __restrict);
248 int	 setvbuf(FILE * __restrict, char * __restrict, int, size_t);
249 int	 sscanf(const char * __restrict, const char * __restrict, ...)
250 		__scanflike(2, 3);
251 FILE	*tmpfile(void);
252 int	 ungetc(int, FILE *);
253 int	 vfprintf(FILE * __restrict, const char * __restrict, __va_list)
254 		__printflike(2, 0);
255 int	 vprintf(const char * __restrict, __va_list)
256 		__printflike(1, 0);
257 
258 int dprintf(int, const char * __restrict, ...) __printflike(2, 3);
259 int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0);
260 
261 #ifndef __AUDIT__
262 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
263 char* gets(char*) __warnattr("gets is very unsafe; consider using fgets");
264 #endif
265 int sprintf(char* __restrict, const char* __restrict, ...)
266     __printflike(2, 3) __warnattr("sprintf is often misused; please use snprintf");
267 char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp");
268 int vsprintf(char* __restrict, const char* __restrict, __va_list)
269     __printflike(2, 0) __warnattr("vsprintf is often misused; please use vsnprintf");
270 #if __XPG_VISIBLE
271 char* tempnam(const char*, const char*)
272     __warnattr("tempnam possibly used unsafely; consider using mkstemp");
273 #endif
274 #endif
275 
276 extern int rename(const char*, const char*);
277 extern int renameat(int, const char*, int, const char*);
278 
279 int	 fgetpos(FILE * __restrict, fpos_t * __restrict);
280 int	 fsetpos(FILE *, const fpos_t *);
281 
282 int	 fseeko(FILE *, off_t, int);
283 off_t	 ftello(FILE *);
284 
285 #if __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE
286 int	 snprintf(char * __restrict, size_t, const char * __restrict, ...)
287 		__printflike(3, 4);
288 int	 vfscanf(FILE * __restrict, const char * __restrict, __va_list)
289 		__scanflike(2, 0);
290 int	 vscanf(const char *, __va_list)
291 		__scanflike(1, 0);
292 int	 vsnprintf(char * __restrict, size_t, const char * __restrict, __va_list)
293 		__printflike(3, 0);
294 int	 vsscanf(const char * __restrict, const char * __restrict, __va_list)
295 		__scanflike(2, 0);
296 #endif /* __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE */
297 
298 /*
299  * Functions defined in POSIX 1003.1.
300  */
301 #if __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE
302 #define	L_ctermid	1024	/* size for ctermid(); PATH_MAX */
303 
304 FILE	*fdopen(int, const char *);
305 int	 fileno(FILE *);
306 
307 #if (__POSIX_VISIBLE >= 199209)
308 int	 pclose(FILE *);
309 FILE	*popen(const char *, const char *);
310 #endif
311 
312 #if __POSIX_VISIBLE >= 199506
313 void	 flockfile(FILE *);
314 int	 ftrylockfile(FILE *);
315 void	 funlockfile(FILE *);
316 
317 /*
318  * These are normally used through macros as defined below, but POSIX
319  * requires functions as well.
320  */
321 int	 getc_unlocked(FILE *);
322 int	 getchar_unlocked(void);
323 int	 putc_unlocked(int, FILE *);
324 int	 putchar_unlocked(int);
325 #endif /* __POSIX_VISIBLE >= 199506 */
326 
327 #endif /* __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE */
328 
329 /*
330  * Routines that are purely local.
331  */
332 #if __BSD_VISIBLE
333 int	 asprintf(char ** __restrict, const char * __restrict, ...)
334 		__printflike(2, 3);
335 char	*fgetln(FILE * __restrict, size_t * __restrict);
336 int	 fpurge(FILE *);
337 void	 setbuffer(FILE *, char *, int);
338 int	 setlinebuf(FILE *);
339 int	 vasprintf(char ** __restrict, const char * __restrict,
340     __va_list)
341 		__printflike(2, 0);
342 
343 /*
344  * Stdio function-access interface.
345  */
346 FILE	*funopen(const void *,
347 		int (*)(void *, char *, int),
348 		int (*)(void *, const char *, int),
349 		fpos_t (*)(void *, fpos_t, int),
350 		int (*)(void *));
351 
352 #define	fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0)
353 #define	fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0)
354 #endif /* __BSD_VISIBLE */
355 
356 extern char* __fgets_chk(char*, int, FILE*, size_t);
357 extern char* __fgets_real(char*, int, FILE*) __RENAME(fgets);
358 __errordecl(__fgets_too_big_error, "fgets called with size bigger than buffer");
359 __errordecl(__fgets_too_small_error, "fgets called with size less than zero");
360 
361 #if defined(__BIONIC_FORTIFY)
362 
363 __BIONIC_FORTIFY_INLINE
364 __printflike(3, 0)
vsnprintf(char * dest,size_t size,const char * format,__va_list ap)365 int vsnprintf(char *dest, size_t size, const char *format, __va_list ap)
366 {
367     return __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, ap);
368 }
369 
370 __BIONIC_FORTIFY_INLINE
371 __printflike(2, 0)
vsprintf(char * dest,const char * format,__va_list ap)372 int vsprintf(char *dest, const char *format, __va_list ap)
373 {
374     return __builtin___vsprintf_chk(dest, 0, __bos(dest), format, ap);
375 }
376 
377 #if defined(__clang__)
378   #if !defined(snprintf)
379     #define __wrap_snprintf(dest, size, ...) __builtin___snprintf_chk(dest, size, 0, __bos(dest), __VA_ARGS__)
380     #define snprintf(...) __wrap_snprintf(__VA_ARGS__)
381   #endif
382 #else
383 __BIONIC_FORTIFY_INLINE
384 __printflike(3, 4)
snprintf(char * dest,size_t size,const char * format,...)385 int snprintf(char *dest, size_t size, const char *format, ...)
386 {
387     return __builtin___snprintf_chk(dest, size, 0,
388         __bos(dest), format, __builtin_va_arg_pack());
389 }
390 #endif
391 
392 #if defined(__clang__)
393   #if !defined(sprintf)
394     #define __wrap_sprintf(dest, ...) __builtin___sprintf_chk(dest, 0, __bos(dest), __VA_ARGS__)
395     #define sprintf(...) __wrap_sprintf(__VA_ARGS__)
396   #endif
397 #else
398 __BIONIC_FORTIFY_INLINE
399 __printflike(2, 3)
sprintf(char * dest,const char * format,...)400 int sprintf(char *dest, const char *format, ...)
401 {
402     return __builtin___sprintf_chk(dest, 0,
403         __bos(dest), format, __builtin_va_arg_pack());
404 }
405 #endif
406 
407 #if !defined(__clang__)
408 
409 __BIONIC_FORTIFY_INLINE
fgets(char * dest,int size,FILE * stream)410 char *fgets(char* dest, int size, FILE* stream) {
411     size_t bos = __bos(dest);
412 
413     // Compiler can prove, at compile time, that the passed in size
414     // is always negative. Force a compiler error.
415     if (__builtin_constant_p(size) && (size < 0)) {
416         __fgets_too_small_error();
417     }
418 
419     // Compiler doesn't know destination size. Don't call __fgets_chk
420     if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
421         return __fgets_real(dest, size, stream);
422     }
423 
424     // Compiler can prove, at compile time, that the passed in size
425     // is always <= the actual object size. Don't call __fgets_chk
426     if (__builtin_constant_p(size) && (size <= (int) bos)) {
427         return __fgets_real(dest, size, stream);
428     }
429 
430     // Compiler can prove, at compile time, that the passed in size
431     // is always > the actual object size. Force a compiler error.
432     if (__builtin_constant_p(size) && (size > (int) bos)) {
433         __fgets_too_big_error();
434     }
435 
436     return __fgets_chk(dest, size, stream, bos);
437 }
438 
439 #endif /* !defined(__clang__) */
440 
441 #endif /* defined(__BIONIC_FORTIFY) */
442 
443 __END_DECLS
444 
445 #endif /* _STDIO_H_ */
446