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 size_t _size; 55 }; 56 57 struct __sFILE { 58 unsigned char* _p; /* current position in (some) buffer */ 59 int _r; /* read space left for getc() */ 60 int _w; /* write space left for putc() */ 61 #if defined(__LP64__) 62 int _flags; /* flags, below; this FILE is free if 0 */ 63 int _file; /* fileno, if Unix descriptor, else -1 */ 64 #else 65 short _flags; /* flags, below; this FILE is free if 0 */ 66 short _file; /* fileno, if Unix descriptor, else -1 */ 67 #endif 68 struct __sbuf _bf; /* the buffer (at least 1 byte, if !NULL) */ 69 int _lbfsize; /* 0 or -_bf._size, for inline putc */ 70 71 // Function pointers used by `funopen`. 72 // Note that `_seek` is ignored if `_seek64` (in __sfileext) is set. 73 // TODO: NetBSD has `funopen2` which corrects the `int`s to `size_t`s. 74 // TODO: glibc has `fopencookie` which passes the function pointers in a struct. 75 void* _cookie; /* cookie passed to io functions */ 76 int (*_close)(void*); 77 int (*_read)(void*, char*, int); 78 fpos_t (*_seek)(void*, fpos_t, int); 79 int (*_write)(void*, const char*, int); 80 81 /* extension data, to avoid further ABI breakage */ 82 struct __sbuf _ext; 83 /* data for long sequences of ungetc() */ 84 unsigned char* _up; /* saved _p when _p is doing ungetc data */ 85 int _ur; /* saved _r when _r is counting ungetc data */ 86 87 /* tricks to meet minimum requirements even when malloc() fails */ 88 unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */ 89 unsigned char _nbuf[1]; /* guarantee a getc() buffer */ 90 91 /* separate buffer for fgetln() when line crosses buffer boundary */ 92 struct __sbuf _lb; /* buffer for fgetln() */ 93 94 /* Unix stdio files get aligned to block boundaries on fseek() */ 95 int _blksize; /* stat.st_blksize (may be != _bf._size) */ 96 97 fpos_t _unused_0; // This was the `_offset` field (see below). 98 99 // Do not add new fields here. (Or remove or change the size of any above.) 100 // Although bionic currently exports `stdin`, `stdout`, and `stderr` symbols, 101 // that still hasn't made it to the NDK. All NDK-built apps index directly 102 // into an array of this struct (which was in <stdio.h> historically), so if 103 // you need to make any changes, they need to be in the `__sfileext` struct 104 // below, and accessed via `_EXT`. 105 }; 106 107 /* minimal requirement of SUSv2 */ 108 #define WCIO_UNGETWC_BUFSIZE 1 109 110 struct wchar_io_data { 111 mbstate_t wcio_mbstate_in; 112 mbstate_t wcio_mbstate_out; 113 114 wchar_t wcio_ungetwc_buf[WCIO_UNGETWC_BUFSIZE]; 115 size_t wcio_ungetwc_inbuf; 116 117 int wcio_mode; /* orientation */ 118 }; 119 120 struct __sfileext { 121 // ungetc buffer. 122 struct __sbuf _ub; 123 124 // Wide char io status. 125 struct wchar_io_data _wcio; 126 127 // File lock. 128 pthread_mutex_t _lock; 129 130 // __fsetlocking support. 131 bool _caller_handles_locking; 132 133 // Equivalent to `_seek` but for _FILE_OFFSET_BITS=64. 134 // Callers should use this but fall back to `__sFILE::_seek`. 135 off64_t (*_seek64)(void*, off64_t, int); 136 137 // The pid of the child if this FILE* is from popen(3). 138 pid_t _popen_pid; 139 }; 140 141 // Values for `__sFILE::_flags`. 142 #define __SLBF 0x0001 // Line buffered. 143 #define __SNBF 0x0002 // Unbuffered. 144 // __SRD and __SWR are mutually exclusive because they indicate what we did last. 145 // If you want to know whether we were opened read-write, check __SRW instead. 146 #define __SRD 0x0004 // Last operation was read. 147 #define __SWR 0x0008 // Last operation was write. 148 #define __SRW 0x0010 // Was opened for reading & writing. 149 #define __SEOF 0x0020 // Found EOF. 150 #define __SERR 0x0040 // Found error. 151 #define __SMBF 0x0080 // `_buf` is from malloc. 152 // #define __SAPP 0x0100 --- historical (fdopen()ed in append mode). 153 #define __SSTR 0x0200 // This is an sprintf/snprintf string. 154 // #define __SOPT 0x0400 --- historical (do fseek() optimization). 155 // #define __SNPT 0x0800 --- historical (do not do fseek() optimization). 156 // #define __SOFF 0x1000 --- historical (set iff _offset is in fact correct). 157 // #define __SMOD 0x2000 --- historical (set iff fgetln modified _p text). 158 #define __SALC 0x4000 // Allocate string space dynamically. 159 #define __SIGN 0x8000 // Ignore this file in _fwalk. 160 161 // TODO: remove remaining references to these obsolete flags (see above). 162 #define __SMOD 0 163 #define __SNPT 0 164 #define __SOPT 0 165 166 #define _EXT(fp) __BIONIC_CAST(reinterpret_cast, struct __sfileext*, (fp)->_ext._base) 167 168 #define _UB(fp) _EXT(fp)->_ub 169 170 #define _FILEEXT_SETUP(fp, fext) \ 171 do { \ 172 (fp)->_ext._base = __BIONIC_CAST(reinterpret_cast, unsigned char*, fext); \ 173 memset(_EXT(fp), 0, sizeof(struct __sfileext)); \ 174 _EXT(fp)->_caller_handles_locking = true; \ 175 } while (0) 176 177 // Android <= 19 had getc/putc macros in <stdio.h> that referred 178 // to __srget/__swbuf, so those symbols need to be public for LP32 179 // but can be hidden for LP64. Moreover, the NDK continued to ship 180 // those macros until r15 made unified headers the default. 181 __LIBC32_LEGACY_PUBLIC__ int __srget(FILE*); 182 __LIBC32_LEGACY_PUBLIC__ int __swbuf(int, FILE*); 183 __LIBC32_LEGACY_PUBLIC__ int __srefill(FILE*); 184 185 /* This was referenced by the apportable middleware for LP32. */ 186 __LIBC32_LEGACY_PUBLIC__ int __swsetup(FILE*); 187 188 /* These were referenced by a couple of different pieces of middleware and the Crystax NDK. */ 189 __LIBC32_LEGACY_PUBLIC__ int __sflags(const char*, int*); 190 __LIBC32_LEGACY_PUBLIC__ FILE* __sfp(void); 191 __LIBC32_LEGACY_PUBLIC__ void __smakebuf(FILE*); 192 193 /* These are referenced by the Greed for Glory franchise. */ 194 __LIBC32_LEGACY_PUBLIC__ int __sflush(FILE*); 195 __LIBC32_LEGACY_PUBLIC__ int __sread(void*, char*, int); 196 __LIBC32_LEGACY_PUBLIC__ int __swrite(void*, const char*, int); 197 __LIBC32_LEGACY_PUBLIC__ fpos_t __sseek(void*, fpos_t, int); 198 __LIBC32_LEGACY_PUBLIC__ int __sclose(void*); 199 __LIBC32_LEGACY_PUBLIC__ int _fwalk(int (*)(FILE*)); 200 201 off64_t __sseek64(void*, off64_t, int); 202 int __sflush_locked(FILE*); 203 int __swhatbuf(FILE*, size_t*, int*); 204 wint_t __fgetwc_unlock(FILE*); 205 wint_t __ungetwc(wint_t, FILE*); 206 int __vfprintf(FILE*, const char*, va_list); 207 int __svfscanf(FILE*, const char*, va_list); 208 int __vfwprintf(FILE*, const wchar_t*, va_list); 209 int __vfwscanf(FILE*, const wchar_t*, va_list); 210 211 /* 212 * Return true if the given FILE cannot be written now. 213 */ 214 #define cantwrite(fp) ((((fp)->_flags & __SWR) == 0 || (fp)->_bf._base == NULL) && __swsetup(fp)) 215 216 /* 217 * Test whether the given stdio file has an active ungetc buffer; 218 * release such a buffer, without restoring ordinary unread data. 219 */ 220 #define HASUB(fp) (_UB(fp)._base != NULL) 221 #define FREEUB(fp) \ 222 { \ 223 if (_UB(fp)._base != (fp)->_ubuf) free(_UB(fp)._base); \ 224 _UB(fp)._base = NULL; \ 225 } 226 227 #define FLOCKFILE(fp) \ 228 if (!_EXT(fp)->_caller_handles_locking) flockfile(fp) 229 #define FUNLOCKFILE(fp) \ 230 if (!_EXT(fp)->_caller_handles_locking) funlockfile(fp) 231 232 /* OpenBSD exposes these in <stdio.h>, but we only want them exposed to the implementation. */ 233 #define __sferror(p) (((p)->_flags & __SERR) != 0) 234 #define __sclearerr(p) ((void)((p)->_flags &= ~(__SERR | __SEOF))) 235 #define __sgetc(p) (--(p)->_r < 0 ? __srget(p) : __BIONIC_CAST(static_cast, int, *(p)->_p++)) 236 237 /* OpenBSD declares these in fvwrite.h, but we share them with C++ parts of the implementation. */ 238 struct __siov { 239 void* iov_base; 240 size_t iov_len; 241 }; 242 struct __suio { 243 struct __siov* uio_iov; 244 int uio_iovcnt; 245 size_t uio_resid; 246 }; 247 int __sfvwrite(FILE*, struct __suio*); 248 wint_t __fputwc_unlock(wchar_t wc, FILE* fp); 249 250 /* Remove the if (!__sdidinit) __sinit() idiom from untouched upstream stdio code. */ 251 extern void __sinit(void); // Not actually implemented. 252 #define __sdidinit 1 253 254 size_t parsefloat(FILE*, char*, char*); 255 size_t wparsefloat(FILE*, wchar_t*, wchar_t*); 256 257 // Check a FILE* isn't nullptr, so we can emit a clear diagnostic message 258 // instead of just crashing with SIGSEGV. 259 #define CHECK_FP(fp) \ 260 if (fp == nullptr) __fortify_fatal("%s: null FILE*", __FUNCTION__) 261 262 /* 263 * Floating point scanf/printf (input/output) definitions. 264 */ 265 266 /* 11-bit exponent (VAX G floating point) is 308 decimal digits */ 267 #define MAXEXP 308 268 /* 128 bit fraction takes up 39 decimal digits; max reasonable precision */ 269 #define MAXFRACT 39 270 271 /* 272 * MAXEXPDIG is the maximum number of decimal digits needed to store a 273 * floating point exponent in the largest supported format. It should 274 * be ceil(log10(LDBL_MAX_10_EXP)) or, if hexadecimal floating point 275 * conversions are supported, ceil(log10(LDBL_MAX_EXP)). But since it 276 * is presently never greater than 5 in practice, we fudge it. 277 */ 278 #define MAXEXPDIG 6 279 #if LDBL_MAX_EXP > 999999 280 #error "floating point buffers too small" 281 #endif 282 283 char* __hdtoa(double, const char*, int, int*, int*, char**); 284 char* __hldtoa(long double, const char*, int, int*, int*, char**); 285 char* __ldtoa(long double*, int, int, int*, int*, char**); 286 287 #define WCIO_GET(fp) (_EXT(fp) ? &(_EXT(fp)->_wcio) : NULL) 288 289 #define ORIENT_BYTES (-1) 290 #define ORIENT_UNKNOWN 0 291 #define ORIENT_CHARS 1 292 293 #define _SET_ORIENTATION(fp, mode) \ 294 do { \ 295 struct wchar_io_data* _wcio = WCIO_GET(fp); \ 296 if (_wcio && _wcio->wcio_mode == ORIENT_UNKNOWN) _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 = ORIENT_UNKNOWN; \ 304 _wcio->wcio_ungetwc_inbuf = 0; \ 305 } \ 306 } while (0) 307 308 __END_DECLS 309