stdio.h revision 430cf1a6c32471ada4dad028acbfcc032da01fd3
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#define _FSTDIO /* Define for new stdio with functions. */ 51 52typedef off_t fpos_t; /* stdio file position type */ 53 54/* 55 * NB: to fit things in six character monocase externals, the stdio 56 * code uses the prefix `__s' for stdio objects, typically followed 57 * by a three-character attempt at a mnemonic. 58 */ 59 60/* stdio buffers */ 61struct __sbuf { 62 unsigned char *_base; 63 int _size; 64}; 65 66/* 67 * stdio state variables. 68 * 69 * The following always hold: 70 * 71 * if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR), 72 * _lbfsize is -_bf._size, else _lbfsize is 0 73 * if _flags&__SRD, _w is 0 74 * if _flags&__SWR, _r is 0 75 * 76 * This ensures that the getc and putc macros (or inline functions) never 77 * try to write or read from a file that is in `read' or `write' mode. 78 * (Moreover, they can, and do, automatically switch from read mode to 79 * write mode, and back, on "r+" and "w+" files.) 80 * 81 * _lbfsize is used only to make the inline line-buffered output stream 82 * code as compact as possible. 83 * 84 * _ub, _up, and _ur are used when ungetc() pushes back more characters 85 * than fit in the current _bf, or when ungetc() pushes back a character 86 * that does not match the previous one in _bf. When this happens, 87 * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff 88 * _ub._base!=NULL) and _up and _ur save the current values of _p and _r. 89 * 90 * NOTE: if you change this structure, you also need to update the 91 * std() initializer in findfp.c. 92 */ 93typedef struct __sFILE { 94 unsigned char *_p; /* current position in (some) buffer */ 95 int _r; /* read space left for getc() */ 96 int _w; /* write space left for putc() */ 97 short _flags; /* flags, below; this FILE is free if 0 */ 98 short _file; /* fileno, if Unix descriptor, else -1 */ 99 struct __sbuf _bf; /* the buffer (at least 1 byte, if !NULL) */ 100 int _lbfsize; /* 0 or -_bf._size, for inline putc */ 101 102 /* operations */ 103 void *_cookie; /* cookie passed to io functions */ 104 int (*_close)(void *); 105 int (*_read)(void *, char *, int); 106 fpos_t (*_seek)(void *, fpos_t, int); 107 int (*_write)(void *, const char *, int); 108 109 /* extension data, to avoid further ABI breakage */ 110 struct __sbuf _ext; 111 /* data for long sequences of ungetc() */ 112 unsigned char *_up; /* saved _p when _p is doing ungetc data */ 113 int _ur; /* saved _r when _r is counting ungetc data */ 114 115 /* tricks to meet minimum requirements even when malloc() fails */ 116 unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */ 117 unsigned char _nbuf[1]; /* guarantee a getc() buffer */ 118 119 /* separate buffer for fgetln() when line crosses buffer boundary */ 120 struct __sbuf _lb; /* buffer for fgetln() */ 121 122 /* Unix stdio files get aligned to block boundaries on fseek() */ 123 int _blksize; /* stat.st_blksize (may be != _bf._size) */ 124 fpos_t _offset; /* current lseek offset */ 125} FILE; 126 127__BEGIN_DECLS 128extern FILE __sF[]; 129__END_DECLS 130 131#define __SLBF 0x0001 /* line buffered */ 132#define __SNBF 0x0002 /* unbuffered */ 133#define __SRD 0x0004 /* OK to read */ 134#define __SWR 0x0008 /* OK to write */ 135 /* RD and WR are never simultaneously asserted */ 136#define __SRW 0x0010 /* open for reading & writing */ 137#define __SEOF 0x0020 /* found EOF */ 138#define __SERR 0x0040 /* found error */ 139#define __SMBF 0x0080 /* _buf is from malloc */ 140#define __SAPP 0x0100 /* fdopen()ed in append mode */ 141#define __SSTR 0x0200 /* this is an sprintf/snprintf string */ 142#define __SOPT 0x0400 /* do fseek() optimization */ 143#define __SNPT 0x0800 /* do not do fseek() optimization */ 144#define __SOFF 0x1000 /* set iff _offset is in fact correct */ 145#define __SMOD 0x2000 /* true => fgetln modified _p text */ 146#define __SALC 0x4000 /* allocate string space dynamically */ 147#define __SIGN 0x8000 /* ignore this file in _fwalk */ 148 149/* 150 * The following three definitions are for ANSI C, which took them 151 * from System V, which brilliantly took internal interface macros and 152 * made them official arguments to setvbuf(), without renaming them. 153 * Hence, these ugly _IOxxx names are *supposed* to appear in user code. 154 * 155 * Although numbered as their counterparts above, the implementation 156 * does not rely on this. 157 */ 158#define _IOFBF 0 /* setvbuf should set fully buffered */ 159#define _IOLBF 1 /* setvbuf should set line buffered */ 160#define _IONBF 2 /* setvbuf should set unbuffered */ 161 162#define BUFSIZ 1024 /* size of buffer used by setbuf */ 163#define EOF (-1) 164 165/* 166 * FOPEN_MAX is a minimum maximum, and is the number of streams that 167 * stdio can provide without attempting to allocate further resources 168 * (which could fail). Do not use this for anything. 169 */ 170 171#define FOPEN_MAX 20 /* must be <= OPEN_MAX <sys/syslimits.h> */ 172#define FILENAME_MAX 1024 /* must be <= PATH_MAX <sys/syslimits.h> */ 173 174/* System V/ANSI C; this is the wrong way to do this, do *not* use these. */ 175#if __BSD_VISIBLE || __XPG_VISIBLE 176#define P_tmpdir "/tmp/" 177#endif 178#define L_tmpnam 1024 /* XXX must be == PATH_MAX */ 179#define TMP_MAX 308915776 180 181/* Always ensure that these are consistent with <fcntl.h> and <unistd.h>! */ 182#ifndef SEEK_SET 183#define SEEK_SET 0 /* set file offset to offset */ 184#endif 185#ifndef SEEK_CUR 186#define SEEK_CUR 1 /* set file offset to current plus offset */ 187#endif 188#ifndef SEEK_END 189#define SEEK_END 2 /* set file offset to EOF plus offset */ 190#endif 191 192#define stdin (&__sF[0]) 193#define stdout (&__sF[1]) 194#define stderr (&__sF[2]) 195 196/* 197 * Functions defined in ANSI C standard. 198 */ 199__BEGIN_DECLS 200void clearerr(FILE *); 201int fclose(FILE *); 202int feof(FILE *); 203int ferror(FILE *); 204int fflush(FILE *); 205int fgetc(FILE *); 206char *fgets(char * __restrict, int, FILE * __restrict); 207FILE *fopen(const char * __restrict , const char * __restrict); 208int fprintf(FILE * __restrict , const char * __restrict, ...) 209 __printflike(2, 3); 210int fputc(int, FILE *); 211int fputs(const char * __restrict, FILE * __restrict); 212size_t fread(void * __restrict, size_t, size_t, FILE * __restrict); 213FILE *freopen(const char * __restrict, const char * __restrict, 214 FILE * __restrict); 215int fscanf(FILE * __restrict, const char * __restrict, ...) 216 __scanflike(2, 3); 217int fseek(FILE *, long, int); 218long ftell(FILE *); 219size_t fwrite(const void * __restrict, size_t, size_t, FILE * __restrict); 220int getc(FILE *); 221int getchar(void); 222ssize_t getdelim(char ** __restrict, size_t * __restrict, int, 223 FILE * __restrict); 224ssize_t getline(char ** __restrict, size_t * __restrict, FILE * __restrict); 225 226#if __BSD_VISIBLE && !defined(__SYS_ERRLIST) 227#define __SYS_ERRLIST 228extern int sys_nerr; /* perror(3) external variables */ 229extern char *sys_errlist[]; 230#endif 231 232void perror(const char *); 233int printf(const char * __restrict, ...) 234 __printflike(1, 2); 235int putc(int, FILE *); 236int putchar(int); 237int puts(const char *); 238int remove(const char *); 239void rewind(FILE *); 240int scanf(const char * __restrict, ...) 241 __scanflike(1, 2); 242void setbuf(FILE * __restrict, char * __restrict); 243int setvbuf(FILE * __restrict, char * __restrict, int, size_t); 244int sscanf(const char * __restrict, const char * __restrict, ...) 245 __scanflike(2, 3); 246FILE *tmpfile(void); 247int ungetc(int, FILE *); 248int vfprintf(FILE * __restrict, const char * __restrict, __va_list) 249 __printflike(2, 0); 250int vprintf(const char * __restrict, __va_list) 251 __printflike(1, 0); 252 253int dprintf(int, const char * __restrict, ...) __printflike(2, 3); 254int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0); 255 256static inline int fdprintf(int fd, const char* fmt, ...) { 257 /* Note: this backward compatibility shim is only in the preview release. */ 258 va_list ap; 259 va_start(ap, fmt); 260 int rc = vdprintf(fd, fmt, ap); 261 va_end(ap); 262 return rc; 263} 264 265#ifndef __AUDIT__ 266char* gets(char*) __warnattr("gets is very unsafe; consider using fgets"); 267int sprintf(char* __restrict, const char* __restrict, ...) 268 __printflike(2, 3) __warnattr("sprintf is often misused; please use snprintf"); 269char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp"); 270int vsprintf(char* __restrict, const char* __restrict, __va_list) 271 __printflike(2, 0) __warnattr("vsprintf is often misused; please use vsnprintf"); 272#if __XPG_VISIBLE 273char* tempnam(const char*, const char*) 274 __warnattr("tempnam possibly used unsafely; consider using mkstemp"); 275#endif 276#endif 277 278extern int rename(const char*, const char*); 279extern int renameat(int, const char*, int, const char*); 280 281int fgetpos(FILE * __restrict, fpos_t * __restrict); 282int fsetpos(FILE *, const fpos_t *); 283 284int fseeko(FILE *, off_t, int); 285off_t ftello(FILE *); 286 287#if __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE 288int snprintf(char * __restrict, size_t, const char * __restrict, ...) 289 __printflike(3, 4); 290int vfscanf(FILE * __restrict, const char * __restrict, __va_list) 291 __scanflike(2, 0); 292int vscanf(const char *, __va_list) 293 __scanflike(1, 0); 294int vsnprintf(char * __restrict, size_t, const char * __restrict, __va_list) 295 __printflike(3, 0); 296int vsscanf(const char * __restrict, const char * __restrict, __va_list) 297 __scanflike(2, 0); 298#endif /* __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE */ 299 300__END_DECLS 301 302 303/* 304 * Functions defined in POSIX 1003.1. 305 */ 306#if __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE 307#define L_ctermid 1024 /* size for ctermid(); PATH_MAX */ 308#define L_cuserid 9 /* size for cuserid(); UT_NAMESIZE + 1 */ 309 310__BEGIN_DECLS 311#if 0 /* MISSING FROM BIONIC */ 312char *ctermid(char *); 313char *cuserid(char *); 314#endif /* MISSING */ 315FILE *fdopen(int, const char *); 316int fileno(FILE *); 317 318#if (__POSIX_VISIBLE >= 199209) 319int pclose(FILE *); 320FILE *popen(const char *, const char *); 321#endif 322 323#if __POSIX_VISIBLE >= 199506 324void flockfile(FILE *); 325int ftrylockfile(FILE *); 326void funlockfile(FILE *); 327 328/* 329 * These are normally used through macros as defined below, but POSIX 330 * requires functions as well. 331 */ 332int getc_unlocked(FILE *); 333int getchar_unlocked(void); 334int putc_unlocked(int, FILE *); 335int putchar_unlocked(int); 336#endif /* __POSIX_VISIBLE >= 199506 */ 337 338__END_DECLS 339 340#endif /* __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE */ 341 342/* 343 * Routines that are purely local. 344 */ 345#if __BSD_VISIBLE 346__BEGIN_DECLS 347int asprintf(char ** __restrict, const char * __restrict, ...) 348 __printflike(2, 3); 349char *fgetln(FILE * __restrict, size_t * __restrict); 350int fpurge(FILE *); 351int getw(FILE *); 352int putw(int, FILE *); 353void setbuffer(FILE *, char *, int); 354int setlinebuf(FILE *); 355int 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 364FILE *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) 380int 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) 387int 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) 400int 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) 415int 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 422extern char* __fgets_chk(char*, int, FILE*, size_t); 423extern 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 430char *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