1 /* $OpenBSD: local.h,v 1.12 2005/10/10 17:37:44 espie Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Chris Torek. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 */ 34 35 #pragma once 36 37 #include <pthread.h> 38 #include <stdbool.h> 39 #include <wchar.h> 40 41 #if defined(__cplusplus) // Until we fork all of stdio... 42 #include "private/bionic_fortify.h" 43 #endif 44 45 /* 46 * Information local to this implementation of stdio, 47 * in particular, macros and private variables. 48 */ 49 50 __BEGIN_DECLS 51 52 struct __sbuf { 53 unsigned char* _base; 54 #if defined(__LP64__) 55 size_t _size; 56 #else 57 int _size; 58 #endif 59 }; 60 61 struct __sFILE { 62 unsigned char* _p; /* current position in (some) buffer */ 63 int _r; /* read space left for getc() */ 64 int _w; /* write space left for putc() */ 65 #if defined(__LP64__) 66 int _flags; /* flags, below; this FILE is free if 0 */ 67 int _file; /* fileno, if Unix descriptor, else -1 */ 68 #else 69 short _flags; /* flags, below; this FILE is free if 0 */ 70 short _file; /* fileno, if Unix descriptor, else -1 */ 71 #endif 72 struct __sbuf _bf; /* the buffer (at least 1 byte, if !NULL) */ 73 int _lbfsize; /* 0 or -_bf._size, for inline putc */ 74 75 // Function pointers used by `funopen`. 76 // Note that `_seek` is ignored if `_seek64` (in __sfileext) is set. 77 // TODO: NetBSD has `funopen2` which corrects the `int`s to `size_t`s. 78 // TODO: glibc has `fopencookie` which passes the function pointers in a struct. 79 void* _cookie; /* cookie passed to io functions */ 80 int (*_close)(void*); 81 int (*_read)(void*, char*, int); 82 fpos_t (*_seek)(void*, fpos_t, int); 83 int (*_write)(void*, const char*, int); 84 85 /* extension data, to avoid further ABI breakage */ 86 struct __sbuf _ext; 87 /* data for long sequences of ungetc() */ 88 unsigned char* _up; /* saved _p when _p is doing ungetc data */ 89 int _ur; /* saved _r when _r is counting ungetc data */ 90 91 /* tricks to meet minimum requirements even when malloc() fails */ 92 unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */ 93 unsigned char _nbuf[1]; /* guarantee a getc() buffer */ 94 95 /* separate buffer for fgetln() when line crosses buffer boundary */ 96 struct __sbuf _lb; /* buffer for fgetln() */ 97 98 /* Unix stdio files get aligned to block boundaries on fseek() */ 99 int _blksize; /* stat.st_blksize (may be != _bf._size) */ 100 101 fpos_t _unused_0; // This was the `_offset` field (see below). 102 103 // Do not add new fields here. (Or remove or change the size of any above.) 104 // Although bionic currently exports `stdin`, `stdout`, and `stderr` symbols, 105 // that still hasn't made it to the NDK. All NDK-built apps index directly 106 // into an array of this struct (which was in <stdio.h> historically), so if 107 // you need to make any changes, they need to be in the `__sfileext` struct 108 // below, and accessed via `_EXT`. 109 }; 110 111 /* minimal requirement of SUSv2 */ 112 #define WCIO_UNGETWC_BUFSIZE 1 113 114 struct wchar_io_data { 115 mbstate_t wcio_mbstate_in; 116 mbstate_t wcio_mbstate_out; 117 118 wchar_t wcio_ungetwc_buf[WCIO_UNGETWC_BUFSIZE]; 119 size_t wcio_ungetwc_inbuf; 120 121 int wcio_mode; /* orientation */ 122 }; 123 124 struct __sfileext { 125 // ungetc buffer. 126 struct __sbuf _ub; 127 128 // Wide char io status. 129 struct wchar_io_data _wcio; 130 131 // File lock. 132 pthread_mutex_t _lock; 133 134 // __fsetlocking support. 135 bool _caller_handles_locking; 136 137 // Equivalent to `_seek` but for _FILE_OFFSET_BITS=64. 138 // Callers should use this but fall back to `__sFILE::_seek`. 139 off64_t (*_seek64)(void*, off64_t, int); 140 }; 141 142 // Values for `__sFILE::_flags`. 143 #define __SLBF 0x0001 // Line buffered. 144 #define __SNBF 0x0002 // Unbuffered. 145 // __SRD and __SWR are mutually exclusive because they indicate what we did last. 146 // If you want to know whether we were opened read-write, check __SRW instead. 147 #define __SRD 0x0004 // Last operation was read. 148 #define __SWR 0x0008 // Last operation was write. 149 #define __SRW 0x0010 // Was opened for reading & writing. 150 #define __SEOF 0x0020 // Found EOF. 151 #define __SERR 0x0040 // Found error. 152 #define __SMBF 0x0080 // `_buf` is from malloc. 153 // #define __SAPP 0x0100 --- historical (fdopen()ed in append mode). 154 #define __SSTR 0x0200 // This is an sprintf/snprintf string. 155 // #define __SOPT 0x0400 --- historical (do fseek() optimization). 156 // #define __SNPT 0x0800 --- historical (do not do fseek() optimization). 157 // #define __SOFF 0x1000 --- historical (set iff _offset is in fact correct). 158 // #define __SMOD 0x2000 --- historical (set iff fgetln modified _p text). 159 #define __SALC 0x4000 // Allocate string space dynamically. 160 #define __SIGN 0x8000 // Ignore this file in _fwalk. 161 162 // TODO: remove remaining references to these obsolete flags (see above). 163 #define __SMOD 0 164 #define __SNPT 0 165 #define __SOPT 0 166 167 #define _EXT(fp) __BIONIC_CAST(reinterpret_cast, struct __sfileext*, (fp)->_ext._base) 168 169 #define _UB(fp) _EXT(fp)->_ub 170 #define _FLOCK(fp) _EXT(fp)->_lock 171 172 #define _FILEEXT_SETUP(fp, fext) \ 173 do { \ 174 (fp)->_ext._base = __BIONIC_CAST(reinterpret_cast, unsigned char*, fext); \ 175 memset(_EXT(fp), 0, sizeof(struct __sfileext)); \ 176 _EXT(fp)->_caller_handles_locking = true; \ 177 } while (0) 178 179 // Android <= 19 had getc/putc macros in <stdio.h> that referred 180 // to __srget/__swbuf, so those symbols need to be public for LP32 181 // but can be hidden for LP64. Moreover, the NDK continued to ship 182 // those macros until r15 made unified headers the default. 183 __LIBC32_LEGACY_PUBLIC__ int __srget(FILE*); 184 __LIBC32_LEGACY_PUBLIC__ int __swbuf(int, FILE*); 185 __LIBC32_LEGACY_PUBLIC__ int __srefill(FILE*); 186 187 /* This was referenced by the apportable middleware for LP32. */ 188 __LIBC32_LEGACY_PUBLIC__ int __swsetup(FILE*); 189 190 /* These were referenced by a couple of different pieces of middleware and the Crystax NDK. */ 191 __LIBC32_LEGACY_PUBLIC__ int __sflags(const char*, int*); 192 __LIBC32_LEGACY_PUBLIC__ FILE* __sfp(void); 193 __LIBC32_LEGACY_PUBLIC__ void __smakebuf(FILE*); 194 195 /* These are referenced by the Greed for Glory franchise. */ 196 __LIBC32_LEGACY_PUBLIC__ int __sflush(FILE*); 197 __LIBC32_LEGACY_PUBLIC__ int __sread(void*, char*, int); 198 __LIBC32_LEGACY_PUBLIC__ int __swrite(void*, const char*, int); 199 __LIBC32_LEGACY_PUBLIC__ fpos_t __sseek(void*, fpos_t, int); 200 __LIBC32_LEGACY_PUBLIC__ int __sclose(void*); 201 __LIBC32_LEGACY_PUBLIC__ int _fwalk(int (*)(FILE*)); 202 203 off64_t __sseek64(void*, off64_t, int); 204 int __sflush_locked(FILE*); 205 int __swhatbuf(FILE*, size_t*, int*); 206 wint_t __fgetwc_unlock(FILE*); 207 wint_t __ungetwc(wint_t, FILE*); 208 int __vfprintf(FILE*, const char*, va_list); 209 int __svfscanf(FILE*, const char*, va_list); 210 int __vfwprintf(FILE*, const wchar_t*, va_list); 211 int __vfwscanf(FILE*, const wchar_t*, va_list); 212 213 /* 214 * Return true if the given FILE cannot be written now. 215 */ 216 #define cantwrite(fp) ((((fp)->_flags & __SWR) == 0 || (fp)->_bf._base == NULL) && __swsetup(fp)) 217 218 /* 219 * Test whether the given stdio file has an active ungetc buffer; 220 * release such a buffer, without restoring ordinary unread data. 221 */ 222 #define HASUB(fp) (_UB(fp)._base != NULL) 223 #define FREEUB(fp) \ 224 { \ 225 if (_UB(fp)._base != (fp)->_ubuf) free(_UB(fp)._base); \ 226 _UB(fp)._base = NULL; \ 227 } 228 229 #define FLOCKFILE(fp) \ 230 if (!_EXT(fp)->_caller_handles_locking) flockfile(fp) 231 #define FUNLOCKFILE(fp) \ 232 if (!_EXT(fp)->_caller_handles_locking) funlockfile(fp) 233 234 #define NO_PRINTF_PERCENT_N 235 236 /* OpenBSD exposes these in <stdio.h>, but we only want them exposed to the implementation. */ 237 #define __sferror(p) (((p)->_flags & __SERR) != 0) 238 #define __sclearerr(p) ((void)((p)->_flags &= ~(__SERR | __SEOF))) 239 #define __sgetc(p) (--(p)->_r < 0 ? __srget(p) : (int)(*(p)->_p++)) 240 241 /* OpenBSD declares these in fvwrite.h, but we share them with C++ parts of the implementation. */ 242 struct __siov { 243 void* iov_base; 244 size_t iov_len; 245 }; 246 struct __suio { 247 struct __siov* uio_iov; 248 int uio_iovcnt; 249 size_t uio_resid; 250 }; 251 int __sfvwrite(FILE*, struct __suio*); 252 wint_t __fputwc_unlock(wchar_t wc, FILE* fp); 253 254 /* Remove the if (!__sdidinit) __sinit() idiom from untouched upstream stdio code. */ 255 extern void __sinit(void); // Not actually implemented. 256 #define __sdidinit 1 257 258 size_t parsefloat(FILE*, char*, char*); 259 size_t wparsefloat(FILE*, wchar_t*, wchar_t*); 260 261 // Sanity check a FILE* for nullptr, so we can emit a message while crashing 262 // instead of doing a blind null-dereference. 263 #define CHECK_FP(fp) \ 264 if (fp == nullptr) __fortify_fatal("%s: null FILE*", __FUNCTION__) 265 266 /* 267 * Floating point scanf/printf (input/output) definitions. 268 */ 269 270 /* 11-bit exponent (VAX G floating point) is 308 decimal digits */ 271 #define MAXEXP 308 272 /* 128 bit fraction takes up 39 decimal digits; max reasonable precision */ 273 #define MAXFRACT 39 274 275 /* 276 * MAXEXPDIG is the maximum number of decimal digits needed to store a 277 * floating point exponent in the largest supported format. It should 278 * be ceil(log10(LDBL_MAX_10_EXP)) or, if hexadecimal floating point 279 * conversions are supported, ceil(log10(LDBL_MAX_EXP)). But since it 280 * is presently never greater than 5 in practice, we fudge it. 281 */ 282 #define MAXEXPDIG 6 283 #if LDBL_MAX_EXP > 999999 284 #error "floating point buffers too small" 285 #endif 286 287 char* __hdtoa(double, const char*, int, int*, int*, char**); 288 char* __hldtoa(long double, const char*, int, int*, int*, char**); 289 char* __ldtoa(long double*, int, int, int*, int*, char**); 290 291 #define WCIO_GET(fp) (_EXT(fp) ? &(_EXT(fp)->_wcio) : (struct wchar_io_data*)0) 292 293 #define _SET_ORIENTATION(fp, mode) \ 294 do { \ 295 struct wchar_io_data* _wcio = WCIO_GET(fp); \ 296 if (_wcio && _wcio->wcio_mode == 0) _wcio->wcio_mode = (mode); \ 297 } while (0) 298 299 #define WCIO_FREE(fp) \ 300 do { \ 301 struct wchar_io_data* _wcio = WCIO_GET(fp); \ 302 if (_wcio) { \ 303 _wcio->wcio_mode = 0; \ 304 _wcio->wcio_ungetwc_inbuf = 0; \ 305 } \ 306 } while (0) 307 308 __END_DECLS 309