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 #ifndef __BIONIC_STDIO_LOCAL_H__
36 #define __BIONIC_STDIO_LOCAL_H__
37
38 #include <pthread.h>
39 #include <stdbool.h>
40 #include <wchar.h>
41 #include "wcio.h"
42
43 /*
44 * Information local to this implementation of stdio,
45 * in particular, macros and private variables.
46 */
47
48 __BEGIN_DECLS
49
50 struct __sbuf {
51 unsigned char* _base;
52 #if defined(__LP64__)
53 size_t _size;
54 #else
55 int _size;
56 #endif
57 };
58
59 struct __sFILE {
60 unsigned char *_p; /* current position in (some) buffer */
61 int _r; /* read space left for getc() */
62 int _w; /* write space left for putc() */
63 #if defined(__LP64__)
64 int _flags; /* flags, below; this FILE is free if 0 */
65 int _file; /* fileno, if Unix descriptor, else -1 */
66 #else
67 short _flags; /* flags, below; this FILE is free if 0 */
68 short _file; /* fileno, if Unix descriptor, else -1 */
69 #endif
70 struct __sbuf _bf; /* the buffer (at least 1 byte, if !NULL) */
71 int _lbfsize; /* 0 or -_bf._size, for inline putc */
72
73 // Function pointers used by `funopen`.
74 // Note that `_seek` is ignored if `_seek64` (in __sfileext) is set.
75 // TODO: NetBSD has `funopen2` which corrects the `int`s to `size_t`s.
76 // TODO: glibc has `fopencookie` which passes the function pointers in a struct.
77 void* _cookie; /* cookie passed to io functions */
78 int (*_close)(void*);
79 int (*_read)(void*, char*, int);
80 fpos_t (*_seek)(void*, fpos_t, int);
81 int (*_write)(void*, const char*, int);
82
83 /* extension data, to avoid further ABI breakage */
84 struct __sbuf _ext;
85 /* data for long sequences of ungetc() */
86 unsigned char *_up; /* saved _p when _p is doing ungetc data */
87 int _ur; /* saved _r when _r is counting ungetc data */
88
89 /* tricks to meet minimum requirements even when malloc() fails */
90 unsigned char _ubuf[3]; /* guarantee an ungetc() buffer */
91 unsigned char _nbuf[1]; /* guarantee a getc() buffer */
92
93 /* separate buffer for fgetln() when line crosses buffer boundary */
94 struct __sbuf _lb; /* buffer for fgetln() */
95
96 /* Unix stdio files get aligned to block boundaries on fseek() */
97 int _blksize; /* stat.st_blksize (may be != _bf._size) */
98
99 fpos_t _unused_0; // This was the `_offset` field (see below).
100
101 // Do not add new fields here. (Or remove or change the size of any above.)
102 // Although bionic currently exports `stdin`, `stdout`, and `stderr` symbols,
103 // that still hasn't made it to the NDK. All NDK-built apps index directly
104 // into an array of this struct (which was in <stdio.h> historically), so if
105 // you need to make any changes, they need to be in the `__sfileext` struct
106 // below, and accessed via `_EXT`.
107 };
108
109 struct __sfileext {
110 // ungetc buffer.
111 struct __sbuf _ub;
112
113 // Wide char io status.
114 struct wchar_io_data _wcio;
115
116 // File lock.
117 pthread_mutex_t _lock;
118
119 // __fsetlocking support.
120 bool _caller_handles_locking;
121
122 // Equivalent to `_seek` but for _FILE_OFFSET_BITS=64.
123 // Callers should use this but fall back to `__sFILE::_seek`.
124 off64_t (*_seek64)(void*, off64_t, int);
125 };
126
127 // Values for `__sFILE::_flags`.
128 #define __SLBF 0x0001 // Line buffered.
129 #define __SNBF 0x0002 // Unbuffered.
130 // RD and WR are never simultaneously asserted: use _SRW instead.
131 #define __SRD 0x0004 // OK to read.
132 #define __SWR 0x0008 // OK to write.
133 #define __SRW 0x0010 // Open for reading & writing.
134 #define __SEOF 0x0020 // Found EOF.
135 #define __SERR 0x0040 // Found error.
136 #define __SMBF 0x0080 // `_buf` is from malloc.
137 #define __SAPP 0x0100 // fdopen()ed in append mode.
138 #define __SSTR 0x0200 // This is an sprintf/snprintf string.
139 // #define __SOPT 0x0400 --- historical (do fseek() optimization).
140 // #define __SNPT 0x0800 --- historical (do not do fseek() optimization).
141 // #define __SOFF 0x1000 --- historical (set iff _offset is in fact correct).
142 #define __SMOD 0x2000 // true => fgetln modified _p text.
143 #define __SALC 0x4000 // Allocate string space dynamically.
144 #define __SIGN 0x8000 // Ignore this file in _fwalk.
145
146 // TODO: remove remaining references to these obsolete flags.
147 #define __SNPT 0
148 #define __SOPT 0
149
150 #if defined(__cplusplus)
151 #define _EXT(fp) reinterpret_cast<__sfileext*>((fp)->_ext._base)
152 #else
153 #define _EXT(fp) ((struct __sfileext *)((fp)->_ext._base))
154 #endif
155
156 #define _UB(fp) _EXT(fp)->_ub
157 #define _FLOCK(fp) _EXT(fp)->_lock
158
159 #define _FILEEXT_INIT(fp) \
160 do { \
161 _UB(fp)._base = NULL; \
162 _UB(fp)._size = 0; \
163 WCIO_INIT(fp); \
164 pthread_mutexattr_t attr; \
165 pthread_mutexattr_init(&attr); \
166 pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); \
167 pthread_mutex_init(&_FLOCK(fp), &attr); \
168 pthread_mutexattr_destroy(&attr); \
169 _EXT(fp)->_caller_handles_locking = false; \
170 } while (0)
171
172 #define _FILEEXT_SETUP(f, fext) \
173 do { \
174 (f)->_ext._base = (unsigned char *)(fext); \
175 _FILEEXT_INIT(f); \
176 } while (0)
177
178 /*
179 * Android <= KitKat 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.
182 */
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 #pragma GCC visibility push(hidden)
204
205 off64_t __sseek64(void*, off64_t, int);
206 int __sflush_locked(FILE *);
207 int __swhatbuf(FILE *, size_t *, int *);
208 wint_t __fgetwc_unlock(FILE *);
209 wint_t __ungetwc(wint_t, FILE *);
210 int __vfprintf(FILE *, const char *, __va_list);
211 int __svfscanf(FILE * __restrict, const char * __restrict, __va_list);
212 int __vfwprintf(FILE * __restrict, const wchar_t * __restrict, __va_list);
213 int __vfwscanf(FILE * __restrict, const wchar_t * __restrict, __va_list);
214
215 /*
216 * Return true if the given FILE cannot be written now.
217 */
218 #define cantwrite(fp) \
219 ((((fp)->_flags & __SWR) == 0 || (fp)->_bf._base == NULL) && \
220 __swsetup(fp))
221
222 /*
223 * Test whether the given stdio file has an active ungetc buffer;
224 * release such a buffer, without restoring ordinary unread data.
225 */
226 #define HASUB(fp) (_UB(fp)._base != NULL)
227 #define FREEUB(fp) { \
228 if (_UB(fp)._base != (fp)->_ubuf) \
229 free(_UB(fp)._base); \
230 _UB(fp)._base = NULL; \
231 }
232
233 /*
234 * test for an fgetln() buffer.
235 */
236 #define HASLB(fp) ((fp)->_lb._base != NULL)
237 #define FREELB(fp) { \
238 free((char *)(fp)->_lb._base); \
239 (fp)->_lb._base = NULL; \
240 }
241
242 #define FLOCKFILE(fp) if (!_EXT(fp)->_caller_handles_locking) flockfile(fp)
243 #define FUNLOCKFILE(fp) if (!_EXT(fp)->_caller_handles_locking) funlockfile(fp)
244
245 #define FLOATING_POINT
246 #define PRINTF_WIDE_CHAR
247 #define SCANF_WIDE_CHAR
248 #define NO_PRINTF_PERCENT_N
249
250 /* OpenBSD exposes these in <stdio.h>, but we only want them exposed to the implementation. */
251 #define __sfeof(p) (((p)->_flags & __SEOF) != 0)
252 #define __sferror(p) (((p)->_flags & __SERR) != 0)
253 #define __sclearerr(p) ((void)((p)->_flags &= ~(__SERR|__SEOF)))
254 #if !defined(__cplusplus)
255 #define __sgetc(p) (--(p)->_r < 0 ? __srget(p) : (int)(*(p)->_p++))
__sputc(int _c,FILE * _p)256 static __inline int __sputc(int _c, FILE* _p) {
257 if (--_p->_w >= 0 || (_p->_w >= _p->_lbfsize && (char)_c != '\n')) {
258 return (*_p->_p++ = _c);
259 } else {
260 return (__swbuf(_c, _p));
261 }
262 }
263 #endif
264
265 /* OpenBSD declares these in fvwrite.h but we want to ensure they're hidden. */
266 struct __suio;
267 extern int __sfvwrite(FILE *, struct __suio *);
268 wint_t __fputwc_unlock(wchar_t wc, FILE *fp);
269
270 /* Remove the if (!__sdidinit) __sinit() idiom from untouched upstream stdio code. */
271 extern void __sinit(void); // Not actually implemented.
272 #define __sdidinit 1
273
274 #pragma GCC visibility pop
275
276 __END_DECLS
277
278 #endif
279