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 /*
42  * This file must contain a reference to __gnuc_va_list so that GCC's
43  * fixincludes knows that that's what's being used for va_list, and so
44  * to leave our <stdio.h> alone. (fixincludes gets in the way of pointing
45  * one toolchain at various different sets of platform headers.)
46  * If you alter this comment, be sure to keep "__gnuc_va_list" in it!
47  */
48 
49 #include <sys/cdefs.h>
50 #include <sys/types.h>
51 
52 #include <stdarg.h>
53 #include <stddef.h>
54 
55 #define __need_NULL
56 #include <stddef.h>
57 
58 #define	_FSTDIO			/* Define for new stdio with functions. */
59 
60 typedef off_t fpos_t;		/* stdio file position type */
61 
62 /*
63  * NB: to fit things in six character monocase externals, the stdio
64  * code uses the prefix `__s' for stdio objects, typically followed
65  * by a three-character attempt at a mnemonic.
66  */
67 
68 /* stdio buffers */
69 #if defined(__LP64__)
70 struct __sbuf {
71   unsigned char* _base;
72   size_t _size;
73 };
74 #else
75 struct __sbuf {
76 	unsigned char *_base;
77 	int	_size;
78 };
79 #endif
80 
81 /*
82  * stdio state variables.
83  *
84  * The following always hold:
85  *
86  *	if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR),
87  *		_lbfsize is -_bf._size, else _lbfsize is 0
88  *	if _flags&__SRD, _w is 0
89  *	if _flags&__SWR, _r is 0
90  *
91  * This ensures that the getc and putc macros (or inline functions) never
92  * try to write or read from a file that is in `read' or `write' mode.
93  * (Moreover, they can, and do, automatically switch from read mode to
94  * write mode, and back, on "r+" and "w+" files.)
95  *
96  * _lbfsize is used only to make the inline line-buffered output stream
97  * code as compact as possible.
98  *
99  * _ub, _up, and _ur are used when ungetc() pushes back more characters
100  * than fit in the current _bf, or when ungetc() pushes back a character
101  * that does not match the previous one in _bf.  When this happens,
102  * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff
103  * _ub._base!=NULL) and _up and _ur save the current values of _p and _r.
104  *
105  * NOTE: if you change this structure, you also need to update the
106  * std() initializer in findfp.c.
107  */
108 typedef	struct __sFILE {
109 	unsigned char *_p;	/* current position in (some) buffer */
110 	int	_r;		/* read space left for getc() */
111 	int	_w;		/* write space left for putc() */
112 #if defined(__LP64__)
113 	int	_flags;		/* flags, below; this FILE is free if 0 */
114 	int	_file;		/* fileno, if Unix descriptor, else -1 */
115 #else
116 	short	_flags;		/* flags, below; this FILE is free if 0 */
117 	short	_file;		/* fileno, if Unix descriptor, else -1 */
118 #endif
119 	struct	__sbuf _bf;	/* the buffer (at least 1 byte, if !NULL) */
120 	int	_lbfsize;	/* 0 or -_bf._size, for inline putc */
121 
122 	/* operations */
123 	void	*_cookie;	/* cookie passed to io functions */
124 	int	(*_close)(void *);
125 	int	(*_read)(void *, char *, int);
126 	fpos_t	(*_seek)(void *, fpos_t, int);
127 	int	(*_write)(void *, const char *, int);
128 
129 	/* extension data, to avoid further ABI breakage */
130 	struct	__sbuf _ext;
131 	/* data for long sequences of ungetc() */
132 	unsigned char *_up;	/* saved _p when _p is doing ungetc data */
133 	int	_ur;		/* saved _r when _r is counting ungetc data */
134 
135 	/* tricks to meet minimum requirements even when malloc() fails */
136 	unsigned char _ubuf[3];	/* guarantee an ungetc() buffer */
137 	unsigned char _nbuf[1];	/* guarantee a getc() buffer */
138 
139 	/* separate buffer for fgetln() when line crosses buffer boundary */
140 	struct	__sbuf _lb;	/* buffer for fgetln() */
141 
142 	/* Unix stdio files get aligned to block boundaries on fseek() */
143 	int	_blksize;	/* stat.st_blksize (may be != _bf._size) */
144 	fpos_t	_offset;	/* current lseek offset */
145 } FILE;
146 
147 __BEGIN_DECLS
148 extern FILE __sF[];
149 __END_DECLS
150 
151 #define	__SLBF	0x0001		/* line buffered */
152 #define	__SNBF	0x0002		/* unbuffered */
153 #define	__SRD	0x0004		/* OK to read */
154 #define	__SWR	0x0008		/* OK to write */
155 	/* RD and WR are never simultaneously asserted */
156 #define	__SRW	0x0010		/* open for reading & writing */
157 #define	__SEOF	0x0020		/* found EOF */
158 #define	__SERR	0x0040		/* found error */
159 #define	__SMBF	0x0080		/* _buf is from malloc */
160 #define	__SAPP	0x0100		/* fdopen()ed in append mode */
161 #define	__SSTR	0x0200		/* this is an sprintf/snprintf string */
162 #define	__SOPT	0x0400		/* do fseek() optimization */
163 #define	__SNPT	0x0800		/* do not do fseek() optimization */
164 #define	__SOFF	0x1000		/* set iff _offset is in fact correct */
165 #define	__SMOD	0x2000		/* true => fgetln modified _p text */
166 #define	__SALC	0x4000		/* allocate string space dynamically */
167 #define	__SIGN	0x8000		/* ignore this file in _fwalk */
168 
169 /*
170  * The following three definitions are for ANSI C, which took them
171  * from System V, which brilliantly took internal interface macros and
172  * made them official arguments to setvbuf(), without renaming them.
173  * Hence, these ugly _IOxxx names are *supposed* to appear in user code.
174  *
175  * Although numbered as their counterparts above, the implementation
176  * does not rely on this.
177  */
178 #define	_IOFBF	0		/* setvbuf should set fully buffered */
179 #define	_IOLBF	1		/* setvbuf should set line buffered */
180 #define	_IONBF	2		/* setvbuf should set unbuffered */
181 
182 #define	BUFSIZ	1024		/* size of buffer used by setbuf */
183 #define	EOF	(-1)
184 
185 /*
186  * FOPEN_MAX is a minimum maximum, and is the number of streams that
187  * stdio can provide without attempting to allocate further resources
188  * (which could fail).  Do not use this for anything.
189  */
190 
191 #define	FOPEN_MAX	20	/* must be <= OPEN_MAX <sys/syslimits.h> */
192 #define	FILENAME_MAX	1024	/* must be <= PATH_MAX <sys/syslimits.h> */
193 
194 /* System V/ANSI C; this is the wrong way to do this, do *not* use these. */
195 #if __BSD_VISIBLE || __XPG_VISIBLE
196 #define	P_tmpdir	"/tmp/"
197 #endif
198 #define	L_tmpnam	1024	/* XXX must be == PATH_MAX */
199 #define	TMP_MAX		308915776
200 
201 /* Always ensure that these are consistent with <fcntl.h> and <unistd.h>! */
202 #ifndef SEEK_SET
203 #define	SEEK_SET	0	/* set file offset to offset */
204 #endif
205 #ifndef SEEK_CUR
206 #define	SEEK_CUR	1	/* set file offset to current plus offset */
207 #endif
208 #ifndef SEEK_END
209 #define	SEEK_END	2	/* set file offset to EOF plus offset */
210 #endif
211 
212 #define	stdin	(&__sF[0])
213 #define	stdout	(&__sF[1])
214 #define	stderr	(&__sF[2])
215 
216 /*
217  * Functions defined in ANSI C standard.
218  */
219 __BEGIN_DECLS
220 void	 clearerr(FILE *);
221 int	 fclose(FILE *);
222 int	 feof(FILE *);
223 int	 ferror(FILE *);
224 int	 fflush(FILE *);
225 int	 fgetc(FILE *);
226 char	*fgets(char * __restrict, int, FILE * __restrict);
227 FILE	*fopen(const char * __restrict , const char * __restrict);
228 int	 fprintf(FILE * __restrict , const char * __restrict, ...)
229 		__printflike(2, 3);
230 int	 fputc(int, FILE *);
231 int	 fputs(const char * __restrict, FILE * __restrict);
232 size_t	 fread(void * __restrict, size_t, size_t, FILE * __restrict);
233 FILE	*freopen(const char * __restrict, const char * __restrict,
234 	    FILE * __restrict);
235 int	 fscanf(FILE * __restrict, const char * __restrict, ...)
236 		__scanflike(2, 3);
237 int	 fseek(FILE *, long, int);
238 long	 ftell(FILE *);
239 size_t	 fwrite(const void * __restrict, size_t, size_t, FILE * __restrict);
240 int	 getc(FILE *);
241 int	 getchar(void);
242 ssize_t	 getdelim(char ** __restrict, size_t * __restrict, int,
243 	    FILE * __restrict);
244 ssize_t	 getline(char ** __restrict, size_t * __restrict, FILE * __restrict);
245 
246 void	 perror(const char *);
247 int	 printf(const char * __restrict, ...)
248 		__printflike(1, 2);
249 int	 putc(int, FILE *);
250 int	 putchar(int);
251 int	 puts(const char *);
252 int	 remove(const char *);
253 void	 rewind(FILE *);
254 int	 scanf(const char * __restrict, ...)
255 		__scanflike(1, 2);
256 void	 setbuf(FILE * __restrict, char * __restrict);
257 int	 setvbuf(FILE * __restrict, char * __restrict, int, size_t);
258 int	 sscanf(const char * __restrict, const char * __restrict, ...)
259 		__scanflike(2, 3);
260 FILE	*tmpfile(void);
261 int	 ungetc(int, FILE *);
262 int	 vfprintf(FILE * __restrict, const char * __restrict, __va_list)
263 		__printflike(2, 0);
264 int	 vprintf(const char * __restrict, __va_list)
265 		__printflike(1, 0);
266 
267 int dprintf(int, const char * __restrict, ...) __printflike(2, 3);
268 int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0);
269 
270 #ifndef __AUDIT__
271 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
272 char* gets(char*) __warnattr("gets is very unsafe; consider using fgets");
273 #endif
274 int sprintf(char* __restrict, const char* __restrict, ...)
275     __printflike(2, 3); //__warnattr("sprintf is often misused; please use snprintf");
276 char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp");
277 int vsprintf(char* __restrict, const char* __restrict, __va_list)
278     __printflike(2, 0); //__warnattr("vsprintf is often misused; please use vsnprintf");
279 #if __XPG_VISIBLE
280 char* tempnam(const char*, const char*)
281     __warnattr("tempnam possibly used unsafely; consider using mkstemp");
282 #endif
283 #endif
284 
285 extern int rename(const char*, const char*);
286 extern int renameat(int, const char*, int, const char*);
287 
288 int	 fgetpos(FILE * __restrict, fpos_t * __restrict);
289 int	 fsetpos(FILE *, const fpos_t *);
290 
291 int	 fseeko(FILE *, off_t, int);
292 off_t	 ftello(FILE *);
293 
294 #if __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE
295 int	 snprintf(char * __restrict, size_t, const char * __restrict, ...)
296 		__printflike(3, 4);
297 int	 vfscanf(FILE * __restrict, const char * __restrict, __va_list)
298 		__scanflike(2, 0);
299 int	 vscanf(const char *, __va_list)
300 		__scanflike(1, 0);
301 int	 vsnprintf(char * __restrict, size_t, const char * __restrict, __va_list)
302 		__printflike(3, 0);
303 int	 vsscanf(const char * __restrict, const char * __restrict, __va_list)
304 		__scanflike(2, 0);
305 #endif /* __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE */
306 
307 __END_DECLS
308 
309 
310 /*
311  * Functions defined in POSIX 1003.1.
312  */
313 #if __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE
314 #define	L_ctermid	1024	/* size for ctermid(); PATH_MAX */
315 
316 __BEGIN_DECLS
317 FILE	*fdopen(int, const char *);
318 int	 fileno(FILE *);
319 
320 #if (__POSIX_VISIBLE >= 199209)
321 int	 pclose(FILE *);
322 FILE	*popen(const char *, const char *);
323 #endif
324 
325 #if __POSIX_VISIBLE >= 199506
326 void	 flockfile(FILE *);
327 int	 ftrylockfile(FILE *);
328 void	 funlockfile(FILE *);
329 
330 /*
331  * These are normally used through macros as defined below, but POSIX
332  * requires functions as well.
333  */
334 int	 getc_unlocked(FILE *);
335 int	 getchar_unlocked(void);
336 int	 putc_unlocked(int, FILE *);
337 int	 putchar_unlocked(int);
338 #endif /* __POSIX_VISIBLE >= 199506 */
339 
340 __END_DECLS
341 
342 #endif /* __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE */
343 
344 /*
345  * Routines that are purely local.
346  */
347 #if __BSD_VISIBLE
348 __BEGIN_DECLS
349 int	 asprintf(char ** __restrict, const char * __restrict, ...)
350 		__printflike(2, 3);
351 char	*fgetln(FILE * __restrict, size_t * __restrict);
352 int	 fpurge(FILE *);
353 void	 setbuffer(FILE *, char *, int);
354 int	 setlinebuf(FILE *);
355 int	 vasprintf(char ** __restrict, const char * __restrict,
356     __va_list)
357 		__printflike(2, 0);
358 __END_DECLS
359 
360 /*
361  * Stdio function-access interface.
362  */
363 __BEGIN_DECLS
364 FILE	*funopen(const void *,
365 		int (*)(void *, char *, int),
366 		int (*)(void *, const char *, int),
367 		fpos_t (*)(void *, fpos_t, int),
368 		int (*)(void *));
369 __END_DECLS
370 #define	fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0)
371 #define	fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0)
372 #endif /* __BSD_VISIBLE */
373 
374 #if defined(__BIONIC_FORTIFY)
375 
376 __BEGIN_DECLS
377 
378 __BIONIC_FORTIFY_INLINE
379 __printflike(3, 0)
vsnprintf(char * dest,size_t size,const char * format,__va_list ap)380 int vsnprintf(char *dest, size_t size, const char *format, __va_list ap)
381 {
382     return __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, ap);
383 }
384 
385 __BIONIC_FORTIFY_INLINE
386 __printflike(2, 0)
vsprintf(char * dest,const char * format,__va_list ap)387 int vsprintf(char *dest, const char *format, __va_list ap)
388 {
389     return __builtin___vsprintf_chk(dest, 0, __bos(dest), format, ap);
390 }
391 
392 #if defined(__clang__)
393   #if !defined(snprintf)
394     #define __wrap_snprintf(dest, size, ...) __builtin___snprintf_chk(dest, size, 0, __bos(dest), __VA_ARGS__)
395     #define snprintf(...) __wrap_snprintf(__VA_ARGS__)
396   #endif
397 #else
398 __BIONIC_FORTIFY_INLINE
399 __printflike(3, 4)
snprintf(char * dest,size_t size,const char * format,...)400 int snprintf(char *dest, size_t size, const char *format, ...)
401 {
402     return __builtin___snprintf_chk(dest, size, 0,
403         __bos(dest), format, __builtin_va_arg_pack());
404 }
405 #endif
406 
407 #if defined(__clang__)
408   #if !defined(sprintf)
409     #define __wrap_sprintf(dest, ...) __builtin___sprintf_chk(dest, 0, __bos(dest), __VA_ARGS__)
410     #define sprintf(...) __wrap_sprintf(__VA_ARGS__)
411   #endif
412 #else
413 __BIONIC_FORTIFY_INLINE
414 __printflike(2, 3)
sprintf(char * dest,const char * format,...)415 int sprintf(char *dest, const char *format, ...)
416 {
417     return __builtin___sprintf_chk(dest, 0,
418         __bos(dest), format, __builtin_va_arg_pack());
419 }
420 #endif
421 
422 extern char* __fgets_chk(char*, int, FILE*, size_t);
423 extern char* __fgets_real(char*, int, FILE*) __asm__(__USER_LABEL_PREFIX__ "fgets");
424 __errordecl(__fgets_too_big_error, "fgets called with size bigger than buffer");
425 __errordecl(__fgets_too_small_error, "fgets called with size less than zero");
426 
427 #if !defined(__clang__)
428 
429 __BIONIC_FORTIFY_INLINE
fgets(char * dest,int size,FILE * stream)430 char *fgets(char* dest, int size, FILE* stream) {
431     size_t bos = __bos(dest);
432 
433     // Compiler can prove, at compile time, that the passed in size
434     // is always negative. Force a compiler error.
435     if (__builtin_constant_p(size) && (size < 0)) {
436         __fgets_too_small_error();
437     }
438 
439     // Compiler doesn't know destination size. Don't call __fgets_chk
440     if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) {
441         return __fgets_real(dest, size, stream);
442     }
443 
444     // Compiler can prove, at compile time, that the passed in size
445     // is always <= the actual object size. Don't call __fgets_chk
446     if (__builtin_constant_p(size) && (size <= (int) bos)) {
447         return __fgets_real(dest, size, stream);
448     }
449 
450     // Compiler can prove, at compile time, that the passed in size
451     // is always > the actual object size. Force a compiler error.
452     if (__builtin_constant_p(size) && (size > (int) bos)) {
453         __fgets_too_big_error();
454     }
455 
456     return __fgets_chk(dest, size, stream, bos);
457 }
458 
459 #endif /* !defined(__clang__) */
460 
461 __END_DECLS
462 
463 #endif /* defined(__BIONIC_FORTIFY) */
464 
465 #endif /* _STDIO_H_ */
466