stdio.h revision 658727e111ed6dee7be5239494f0764f7b1b02f8
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__BEGIN_DECLS 59 60#define _FSTDIO /* Define for new stdio with functions. */ 61 62typedef off_t fpos_t; /* stdio file position type */ 63 64/* 65 * NB: to fit things in six character monocase externals, the stdio 66 * code uses the prefix `__s' for stdio objects, typically followed 67 * by a three-character attempt at a mnemonic. 68 */ 69 70/* stdio buffers */ 71#if defined(__LP64__) 72struct __sbuf { 73 unsigned char* _base; 74 size_t _size; 75}; 76#else 77struct __sbuf { 78 unsigned char *_base; 79 int _size; 80}; 81#endif 82 83/* 84 * stdio state variables. 85 * 86 * The following always hold: 87 * 88 * if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR), 89 * _lbfsize is -_bf._size, else _lbfsize is 0 90 * if _flags&__SRD, _w is 0 91 * if _flags&__SWR, _r is 0 92 * 93 * This ensures that the getc and putc macros (or inline functions) never 94 * try to write or read from a file that is in `read' or `write' mode. 95 * (Moreover, they can, and do, automatically switch from read mode to 96 * write mode, and back, on "r+" and "w+" files.) 97 * 98 * _lbfsize is used only to make the inline line-buffered output stream 99 * code as compact as possible. 100 * 101 * _ub, _up, and _ur are used when ungetc() pushes back more characters 102 * than fit in the current _bf, or when ungetc() pushes back a character 103 * that does not match the previous one in _bf. When this happens, 104 * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff 105 * _ub._base!=NULL) and _up and _ur save the current values of _p and _r. 106 * 107 * NOTE: if you change this structure, you also need to update the 108 * std() initializer in findfp.c. 109 */ 110typedef struct __sFILE { 111 unsigned char *_p; /* current position in (some) buffer */ 112 int _r; /* read space left for getc() */ 113 int _w; /* write space left for putc() */ 114#if defined(__LP64__) 115 int _flags; /* flags, below; this FILE is free if 0 */ 116 int _file; /* fileno, if Unix descriptor, else -1 */ 117#else 118 short _flags; /* flags, below; this FILE is free if 0 */ 119 short _file; /* fileno, if Unix descriptor, else -1 */ 120#endif 121 struct __sbuf _bf; /* the buffer (at least 1 byte, if !NULL) */ 122 int _lbfsize; /* 0 or -_bf._size, for inline putc */ 123 124 /* operations */ 125 void *_cookie; /* cookie passed to io functions */ 126 int (*_close)(void *); 127 int (*_read)(void *, char *, int); 128 fpos_t (*_seek)(void *, fpos_t, int); 129 int (*_write)(void *, const char *, int); 130 131 /* extension data, to avoid further ABI breakage */ 132 struct __sbuf _ext; 133 /* data for long sequences of ungetc() */ 134 unsigned char *_up; /* saved _p when _p is doing ungetc data */ 135 int _ur; /* saved _r when _r is counting ungetc data */ 136 137 /* tricks to meet minimum requirements even when malloc() fails */ 138 unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */ 139 unsigned char _nbuf[1]; /* guarantee a getc() buffer */ 140 141 /* separate buffer for fgetln() when line crosses buffer boundary */ 142 struct __sbuf _lb; /* buffer for fgetln() */ 143 144 /* Unix stdio files get aligned to block boundaries on fseek() */ 145 int _blksize; /* stat.st_blksize (may be != _bf._size) */ 146 fpos_t _offset; /* current lseek offset */ 147} FILE; 148 149extern FILE __sF[]; 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 */ 219void clearerr(FILE *); 220int fclose(FILE *); 221int feof(FILE *); 222int ferror(FILE *); 223int fflush(FILE *); 224int fgetc(FILE *); 225char *fgets(char * __restrict, int, FILE * __restrict); 226FILE *fopen(const char * __restrict , const char * __restrict); 227int fprintf(FILE * __restrict , const char * __restrict, ...) 228 __printflike(2, 3); 229int fputc(int, FILE *); 230int fputs(const char * __restrict, FILE * __restrict); 231size_t fread(void * __restrict, size_t, size_t, FILE * __restrict); 232FILE *freopen(const char * __restrict, const char * __restrict, 233 FILE * __restrict); 234int fscanf(FILE * __restrict, const char * __restrict, ...) 235 __scanflike(2, 3); 236int fseek(FILE *, long, int); 237long ftell(FILE *); 238size_t fwrite(const void * __restrict, size_t, size_t, FILE * __restrict); 239int getc(FILE *); 240int getchar(void); 241ssize_t getdelim(char ** __restrict, size_t * __restrict, int, 242 FILE * __restrict); 243ssize_t getline(char ** __restrict, size_t * __restrict, FILE * __restrict); 244 245void perror(const char *); 246int printf(const char * __restrict, ...) 247 __printflike(1, 2); 248int putc(int, FILE *); 249int putchar(int); 250int puts(const char *); 251int remove(const char *); 252void rewind(FILE *); 253int scanf(const char * __restrict, ...) 254 __scanflike(1, 2); 255void setbuf(FILE * __restrict, char * __restrict); 256int setvbuf(FILE * __restrict, char * __restrict, int, size_t); 257int sscanf(const char * __restrict, const char * __restrict, ...) 258 __scanflike(2, 3); 259FILE *tmpfile(void); 260int ungetc(int, FILE *); 261int vfprintf(FILE * __restrict, const char * __restrict, __va_list) 262 __printflike(2, 0); 263int vprintf(const char * __restrict, __va_list) 264 __printflike(1, 0); 265 266int dprintf(int, const char * __restrict, ...) __printflike(2, 3); 267int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0); 268 269#ifndef __AUDIT__ 270#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L 271char* gets(char*) __warnattr("gets is very unsafe; consider using fgets"); 272#endif 273int sprintf(char* __restrict, const char* __restrict, ...) 274 __printflike(2, 3) __warnattr("sprintf is often misused; please use snprintf"); 275char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp"); 276int vsprintf(char* __restrict, const char* __restrict, __va_list) 277 __printflike(2, 0) __warnattr("vsprintf is often misused; please use vsnprintf"); 278#if __XPG_VISIBLE 279char* tempnam(const char*, const char*) 280 __warnattr("tempnam possibly used unsafely; consider using mkstemp"); 281#endif 282#endif 283 284extern int rename(const char*, const char*); 285extern int renameat(int, const char*, int, const char*); 286 287int fgetpos(FILE * __restrict, fpos_t * __restrict); 288int fsetpos(FILE *, const fpos_t *); 289 290int fseeko(FILE *, off_t, int); 291off_t ftello(FILE *); 292 293#if __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE 294int snprintf(char * __restrict, size_t, const char * __restrict, ...) 295 __printflike(3, 4); 296int vfscanf(FILE * __restrict, const char * __restrict, __va_list) 297 __scanflike(2, 0); 298int vscanf(const char *, __va_list) 299 __scanflike(1, 0); 300int vsnprintf(char * __restrict, size_t, const char * __restrict, __va_list) 301 __printflike(3, 0); 302int vsscanf(const char * __restrict, const char * __restrict, __va_list) 303 __scanflike(2, 0); 304#endif /* __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE */ 305 306/* 307 * Functions defined in POSIX 1003.1. 308 */ 309#if __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE 310#define L_ctermid 1024 /* size for ctermid(); PATH_MAX */ 311 312FILE *fdopen(int, const char *); 313int fileno(FILE *); 314 315#if (__POSIX_VISIBLE >= 199209) 316int pclose(FILE *); 317FILE *popen(const char *, const char *); 318#endif 319 320#if __POSIX_VISIBLE >= 199506 321void flockfile(FILE *); 322int ftrylockfile(FILE *); 323void funlockfile(FILE *); 324 325/* 326 * These are normally used through macros as defined below, but POSIX 327 * requires functions as well. 328 */ 329int getc_unlocked(FILE *); 330int getchar_unlocked(void); 331int putc_unlocked(int, FILE *); 332int putchar_unlocked(int); 333#endif /* __POSIX_VISIBLE >= 199506 */ 334 335#if __POSIX_VISIBLE >= 200809 336FILE* fmemopen(void*, size_t, const char*); 337FILE* open_memstream(char**, size_t*); 338#endif /* __POSIX_VISIBLE >= 200809 */ 339 340#endif /* __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE */ 341 342/* 343 * Routines that are purely local. 344 */ 345#if __BSD_VISIBLE 346int asprintf(char ** __restrict, const char * __restrict, ...) 347 __printflike(2, 3); 348char *fgetln(FILE * __restrict, size_t * __restrict); 349int fpurge(FILE *); 350void setbuffer(FILE *, char *, int); 351int setlinebuf(FILE *); 352int vasprintf(char ** __restrict, const char * __restrict, 353 __va_list) 354 __printflike(2, 0); 355 356void clearerr_unlocked(FILE*); 357int feof_unlocked(FILE*); 358int ferror_unlocked(FILE*); 359 360/* 361 * Stdio function-access interface. 362 */ 363FILE *funopen(const void *, 364 int (*)(void *, char *, int), 365 int (*)(void *, const char *, int), 366 fpos_t (*)(void *, fpos_t, int), 367 int (*)(void *)); 368 369#define fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0) 370#define fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0) 371#endif /* __BSD_VISIBLE */ 372 373extern char* __fgets_chk(char*, int, FILE*, size_t); 374extern char* __fgets_real(char*, int, FILE*) __RENAME(fgets); 375__errordecl(__fgets_too_big_error, "fgets called with size bigger than buffer"); 376__errordecl(__fgets_too_small_error, "fgets called with size less than zero"); 377 378#if defined(__BIONIC_FORTIFY) 379 380__BIONIC_FORTIFY_INLINE 381__printflike(3, 0) 382int vsnprintf(char *dest, size_t size, const char *format, __va_list ap) 383{ 384 return __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, ap); 385} 386 387__BIONIC_FORTIFY_INLINE 388__printflike(2, 0) 389int vsprintf(char *dest, const char *format, __va_list ap) 390{ 391 return __builtin___vsprintf_chk(dest, 0, __bos(dest), format, ap); 392} 393 394#if defined(__clang__) 395 #if !defined(snprintf) 396 #define __wrap_snprintf(dest, size, ...) __builtin___snprintf_chk(dest, size, 0, __bos(dest), __VA_ARGS__) 397 #define snprintf(...) __wrap_snprintf(__VA_ARGS__) 398 #endif 399#else 400__BIONIC_FORTIFY_INLINE 401__printflike(3, 4) 402int snprintf(char *dest, size_t size, const char *format, ...) 403{ 404 return __builtin___snprintf_chk(dest, size, 0, 405 __bos(dest), format, __builtin_va_arg_pack()); 406} 407#endif 408 409#if defined(__clang__) 410 #if !defined(sprintf) 411 #define __wrap_sprintf(dest, ...) __builtin___sprintf_chk(dest, 0, __bos(dest), __VA_ARGS__) 412 #define sprintf(...) __wrap_sprintf(__VA_ARGS__) 413 #endif 414#else 415__BIONIC_FORTIFY_INLINE 416__printflike(2, 3) 417int sprintf(char *dest, const char *format, ...) 418{ 419 return __builtin___sprintf_chk(dest, 0, 420 __bos(dest), format, __builtin_va_arg_pack()); 421} 422#endif 423 424#if !defined(__clang__) 425 426__BIONIC_FORTIFY_INLINE 427char *fgets(char* dest, int size, FILE* stream) { 428 size_t bos = __bos(dest); 429 430 // Compiler can prove, at compile time, that the passed in size 431 // is always negative. Force a compiler error. 432 if (__builtin_constant_p(size) && (size < 0)) { 433 __fgets_too_small_error(); 434 } 435 436 // Compiler doesn't know destination size. Don't call __fgets_chk 437 if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) { 438 return __fgets_real(dest, size, stream); 439 } 440 441 // Compiler can prove, at compile time, that the passed in size 442 // is always <= the actual object size. Don't call __fgets_chk 443 if (__builtin_constant_p(size) && (size <= (int) bos)) { 444 return __fgets_real(dest, size, stream); 445 } 446 447 // Compiler can prove, at compile time, that the passed in size 448 // is always > the actual object size. Force a compiler error. 449 if (__builtin_constant_p(size) && (size > (int) bos)) { 450 __fgets_too_big_error(); 451 } 452 453 return __fgets_chk(dest, size, stream, bos); 454} 455 456#endif /* !defined(__clang__) */ 457 458#endif /* defined(__BIONIC_FORTIFY) */ 459 460__END_DECLS 461 462#endif /* _STDIO_H_ */ 463