stdio.h revision 2b021e10664c3938249eb18b48eeac253cbb3e20
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 60typedef 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 */ 69struct __sbuf { 70 unsigned char *_base; 71 int _size; 72}; 73 74/* 75 * stdio state variables. 76 * 77 * The following always hold: 78 * 79 * if (_flags&(__SLBF|__SWR)) == (__SLBF|__SWR), 80 * _lbfsize is -_bf._size, else _lbfsize is 0 81 * if _flags&__SRD, _w is 0 82 * if _flags&__SWR, _r is 0 83 * 84 * This ensures that the getc and putc macros (or inline functions) never 85 * try to write or read from a file that is in `read' or `write' mode. 86 * (Moreover, they can, and do, automatically switch from read mode to 87 * write mode, and back, on "r+" and "w+" files.) 88 * 89 * _lbfsize is used only to make the inline line-buffered output stream 90 * code as compact as possible. 91 * 92 * _ub, _up, and _ur are used when ungetc() pushes back more characters 93 * than fit in the current _bf, or when ungetc() pushes back a character 94 * that does not match the previous one in _bf. When this happens, 95 * _ub._base becomes non-nil (i.e., a stream has ungetc() data iff 96 * _ub._base!=NULL) and _up and _ur save the current values of _p and _r. 97 * 98 * NOTE: if you change this structure, you also need to update the 99 * std() initializer in findfp.c. 100 */ 101typedef struct __sFILE { 102 unsigned char *_p; /* current position in (some) buffer */ 103 int _r; /* read space left for getc() */ 104 int _w; /* write space left for putc() */ 105 short _flags; /* flags, below; this FILE is free if 0 */ 106 short _file; /* fileno, if Unix descriptor, else -1 */ 107 struct __sbuf _bf; /* the buffer (at least 1 byte, if !NULL) */ 108 int _lbfsize; /* 0 or -_bf._size, for inline putc */ 109 110 /* operations */ 111 void *_cookie; /* cookie passed to io functions */ 112 int (*_close)(void *); 113 int (*_read)(void *, char *, int); 114 fpos_t (*_seek)(void *, fpos_t, int); 115 int (*_write)(void *, const char *, int); 116 117 /* extension data, to avoid further ABI breakage */ 118 struct __sbuf _ext; 119 /* data for long sequences of ungetc() */ 120 unsigned char *_up; /* saved _p when _p is doing ungetc data */ 121 int _ur; /* saved _r when _r is counting ungetc data */ 122 123 /* tricks to meet minimum requirements even when malloc() fails */ 124 unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */ 125 unsigned char _nbuf[1]; /* guarantee a getc() buffer */ 126 127 /* separate buffer for fgetln() when line crosses buffer boundary */ 128 struct __sbuf _lb; /* buffer for fgetln() */ 129 130 /* Unix stdio files get aligned to block boundaries on fseek() */ 131 int _blksize; /* stat.st_blksize (may be != _bf._size) */ 132 fpos_t _offset; /* current lseek offset */ 133} FILE; 134 135__BEGIN_DECLS 136extern FILE __sF[]; 137__END_DECLS 138 139#define __SLBF 0x0001 /* line buffered */ 140#define __SNBF 0x0002 /* unbuffered */ 141#define __SRD 0x0004 /* OK to read */ 142#define __SWR 0x0008 /* OK to write */ 143 /* RD and WR are never simultaneously asserted */ 144#define __SRW 0x0010 /* open for reading & writing */ 145#define __SEOF 0x0020 /* found EOF */ 146#define __SERR 0x0040 /* found error */ 147#define __SMBF 0x0080 /* _buf is from malloc */ 148#define __SAPP 0x0100 /* fdopen()ed in append mode */ 149#define __SSTR 0x0200 /* this is an sprintf/snprintf string */ 150#define __SOPT 0x0400 /* do fseek() optimization */ 151#define __SNPT 0x0800 /* do not do fseek() optimization */ 152#define __SOFF 0x1000 /* set iff _offset is in fact correct */ 153#define __SMOD 0x2000 /* true => fgetln modified _p text */ 154#define __SALC 0x4000 /* allocate string space dynamically */ 155#define __SIGN 0x8000 /* ignore this file in _fwalk */ 156 157/* 158 * The following three definitions are for ANSI C, which took them 159 * from System V, which brilliantly took internal interface macros and 160 * made them official arguments to setvbuf(), without renaming them. 161 * Hence, these ugly _IOxxx names are *supposed* to appear in user code. 162 * 163 * Although numbered as their counterparts above, the implementation 164 * does not rely on this. 165 */ 166#define _IOFBF 0 /* setvbuf should set fully buffered */ 167#define _IOLBF 1 /* setvbuf should set line buffered */ 168#define _IONBF 2 /* setvbuf should set unbuffered */ 169 170#define BUFSIZ 1024 /* size of buffer used by setbuf */ 171#define EOF (-1) 172 173/* 174 * FOPEN_MAX is a minimum maximum, and is the number of streams that 175 * stdio can provide without attempting to allocate further resources 176 * (which could fail). Do not use this for anything. 177 */ 178 179#define FOPEN_MAX 20 /* must be <= OPEN_MAX <sys/syslimits.h> */ 180#define FILENAME_MAX 1024 /* must be <= PATH_MAX <sys/syslimits.h> */ 181 182/* System V/ANSI C; this is the wrong way to do this, do *not* use these. */ 183#if __BSD_VISIBLE || __XPG_VISIBLE 184#define P_tmpdir "/tmp/" 185#endif 186#define L_tmpnam 1024 /* XXX must be == PATH_MAX */ 187#define TMP_MAX 308915776 188 189/* Always ensure that these are consistent with <fcntl.h> and <unistd.h>! */ 190#ifndef SEEK_SET 191#define SEEK_SET 0 /* set file offset to offset */ 192#endif 193#ifndef SEEK_CUR 194#define SEEK_CUR 1 /* set file offset to current plus offset */ 195#endif 196#ifndef SEEK_END 197#define SEEK_END 2 /* set file offset to EOF plus offset */ 198#endif 199 200#define stdin (&__sF[0]) 201#define stdout (&__sF[1]) 202#define stderr (&__sF[2]) 203 204/* 205 * Functions defined in ANSI C standard. 206 */ 207__BEGIN_DECLS 208void clearerr(FILE *); 209int fclose(FILE *); 210int feof(FILE *); 211int ferror(FILE *); 212int fflush(FILE *); 213int fgetc(FILE *); 214char *fgets(char * __restrict, int, FILE * __restrict); 215FILE *fopen(const char * __restrict , const char * __restrict); 216int fprintf(FILE * __restrict , const char * __restrict, ...) 217 __printflike(2, 3); 218int fputc(int, FILE *); 219int fputs(const char * __restrict, FILE * __restrict); 220size_t fread(void * __restrict, size_t, size_t, FILE * __restrict); 221FILE *freopen(const char * __restrict, const char * __restrict, 222 FILE * __restrict); 223int fscanf(FILE * __restrict, const char * __restrict, ...) 224 __scanflike(2, 3); 225int fseek(FILE *, long, int); 226long ftell(FILE *); 227size_t fwrite(const void * __restrict, size_t, size_t, FILE * __restrict); 228int getc(FILE *); 229int getchar(void); 230ssize_t getdelim(char ** __restrict, size_t * __restrict, int, 231 FILE * __restrict); 232ssize_t getline(char ** __restrict, size_t * __restrict, FILE * __restrict); 233 234void perror(const char *); 235int printf(const char * __restrict, ...) 236 __printflike(1, 2); 237int putc(int, FILE *); 238int putchar(int); 239int puts(const char *); 240int remove(const char *); 241void rewind(FILE *); 242int scanf(const char * __restrict, ...) 243 __scanflike(1, 2); 244void setbuf(FILE * __restrict, char * __restrict); 245int setvbuf(FILE * __restrict, char * __restrict, int, size_t); 246int sscanf(const char * __restrict, const char * __restrict, ...) 247 __scanflike(2, 3); 248FILE *tmpfile(void); 249int ungetc(int, FILE *); 250int vfprintf(FILE * __restrict, const char * __restrict, __va_list) 251 __printflike(2, 0); 252int vprintf(const char * __restrict, __va_list) 253 __printflike(1, 0); 254 255int dprintf(int, const char * __restrict, ...) __printflike(2, 3); 256int vdprintf(int, const char * __restrict, __va_list) __printflike(2, 0); 257 258#ifndef __AUDIT__ 259#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L 260char* gets(char*) __warnattr("gets is very unsafe; consider using fgets"); 261#endif 262int sprintf(char* __restrict, const char* __restrict, ...) 263 __printflike(2, 3) __warnattr("sprintf is often misused; please use snprintf"); 264char* tmpnam(char*) __warnattr("tmpnam possibly used unsafely; consider using mkstemp"); 265int vsprintf(char* __restrict, const char* __restrict, __va_list) 266 __printflike(2, 0) __warnattr("vsprintf is often misused; please use vsnprintf"); 267#if __XPG_VISIBLE 268char* tempnam(const char*, const char*) 269 __warnattr("tempnam possibly used unsafely; consider using mkstemp"); 270#endif 271#endif 272 273extern int rename(const char*, const char*); 274extern int renameat(int, const char*, int, const char*); 275 276int fgetpos(FILE * __restrict, fpos_t * __restrict); 277int fsetpos(FILE *, const fpos_t *); 278 279int fseeko(FILE *, off_t, int); 280off_t ftello(FILE *); 281 282#if __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE 283int snprintf(char * __restrict, size_t, const char * __restrict, ...) 284 __printflike(3, 4); 285int vfscanf(FILE * __restrict, const char * __restrict, __va_list) 286 __scanflike(2, 0); 287int vscanf(const char *, __va_list) 288 __scanflike(1, 0); 289int vsnprintf(char * __restrict, size_t, const char * __restrict, __va_list) 290 __printflike(3, 0); 291int vsscanf(const char * __restrict, const char * __restrict, __va_list) 292 __scanflike(2, 0); 293#endif /* __ISO_C_VISIBLE >= 1999 || __BSD_VISIBLE */ 294 295__END_DECLS 296 297 298/* 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__BEGIN_DECLS 305FILE *fdopen(int, const char *); 306int fileno(FILE *); 307 308#if (__POSIX_VISIBLE >= 199209) 309int pclose(FILE *); 310FILE *popen(const char *, const char *); 311#endif 312 313#if __POSIX_VISIBLE >= 199506 314void flockfile(FILE *); 315int ftrylockfile(FILE *); 316void funlockfile(FILE *); 317 318/* 319 * These are normally used through macros as defined below, but POSIX 320 * requires functions as well. 321 */ 322int getc_unlocked(FILE *); 323int getchar_unlocked(void); 324int putc_unlocked(int, FILE *); 325int putchar_unlocked(int); 326#endif /* __POSIX_VISIBLE >= 199506 */ 327 328__END_DECLS 329 330#endif /* __BSD_VISIBLE || __POSIX_VISIBLE || __XPG_VISIBLE */ 331 332/* 333 * Routines that are purely local. 334 */ 335#if __BSD_VISIBLE 336__BEGIN_DECLS 337int asprintf(char ** __restrict, const char * __restrict, ...) 338 __printflike(2, 3); 339char *fgetln(FILE * __restrict, size_t * __restrict); 340int fpurge(FILE *); 341void setbuffer(FILE *, char *, int); 342int setlinebuf(FILE *); 343int vasprintf(char ** __restrict, const char * __restrict, 344 __va_list) 345 __printflike(2, 0); 346 347void clearerr_unlocked(FILE*); 348int feof_unlocked(FILE*); 349int ferror_unlocked(FILE*); 350 351__END_DECLS 352 353/* 354 * Stdio function-access interface. 355 */ 356__BEGIN_DECLS 357FILE *funopen(const void *, 358 int (*)(void *, char *, int), 359 int (*)(void *, const char *, int), 360 fpos_t (*)(void *, fpos_t, int), 361 int (*)(void *)); 362__END_DECLS 363#define fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0) 364#define fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0) 365#endif /* __BSD_VISIBLE */ 366 367#if defined(__BIONIC_FORTIFY) 368 369__BEGIN_DECLS 370 371__BIONIC_FORTIFY_INLINE 372__printflike(3, 0) 373int vsnprintf(char *dest, size_t size, const char *format, __va_list ap) 374{ 375 return __builtin___vsnprintf_chk(dest, size, 0, __bos(dest), format, ap); 376} 377 378__BIONIC_FORTIFY_INLINE 379__printflike(2, 0) 380int vsprintf(char *dest, const char *format, __va_list ap) 381{ 382 return __builtin___vsprintf_chk(dest, 0, __bos(dest), format, ap); 383} 384 385#if defined(__clang__) 386 #if !defined(snprintf) 387 #define __wrap_snprintf(dest, size, ...) __builtin___snprintf_chk(dest, size, 0, __bos(dest), __VA_ARGS__) 388 #define snprintf(...) __wrap_snprintf(__VA_ARGS__) 389 #endif 390#else 391__BIONIC_FORTIFY_INLINE 392__printflike(3, 4) 393int snprintf(char *dest, size_t size, const char *format, ...) 394{ 395 return __builtin___snprintf_chk(dest, size, 0, 396 __bos(dest), format, __builtin_va_arg_pack()); 397} 398#endif 399 400#if defined(__clang__) 401 #if !defined(sprintf) 402 #define __wrap_sprintf(dest, ...) __builtin___sprintf_chk(dest, 0, __bos(dest), __VA_ARGS__) 403 #define sprintf(...) __wrap_sprintf(__VA_ARGS__) 404 #endif 405#else 406__BIONIC_FORTIFY_INLINE 407__printflike(2, 3) 408int sprintf(char *dest, const char *format, ...) 409{ 410 return __builtin___sprintf_chk(dest, 0, 411 __bos(dest), format, __builtin_va_arg_pack()); 412} 413#endif 414 415extern char* __fgets_chk(char*, int, FILE*, size_t); 416extern char* __fgets_real(char*, int, FILE*) __RENAME(fgets); 417__errordecl(__fgets_too_big_error, "fgets called with size bigger than buffer"); 418__errordecl(__fgets_too_small_error, "fgets called with size less than zero"); 419 420#if !defined(__clang__) 421 422__BIONIC_FORTIFY_INLINE 423char *fgets(char* dest, int size, FILE* stream) { 424 size_t bos = __bos(dest); 425 426 // Compiler can prove, at compile time, that the passed in size 427 // is always negative. Force a compiler error. 428 if (__builtin_constant_p(size) && (size < 0)) { 429 __fgets_too_small_error(); 430 } 431 432 // Compiler doesn't know destination size. Don't call __fgets_chk 433 if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) { 434 return __fgets_real(dest, size, stream); 435 } 436 437 // Compiler can prove, at compile time, that the passed in size 438 // is always <= the actual object size. Don't call __fgets_chk 439 if (__builtin_constant_p(size) && (size <= (int) bos)) { 440 return __fgets_real(dest, size, stream); 441 } 442 443 // Compiler can prove, at compile time, that the passed in size 444 // is always > the actual object size. Force a compiler error. 445 if (__builtin_constant_p(size) && (size > (int) bos)) { 446 __fgets_too_big_error(); 447 } 448 449 return __fgets_chk(dest, size, stream, bos); 450} 451 452#endif /* !defined(__clang__) */ 453 454__END_DECLS 455 456#endif /* defined(__BIONIC_FORTIFY) */ 457 458#endif /* _STDIO_H_ */ 459