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 #define _EXT(fp) __BIONIC_CAST(reinterpret_cast, struct __sfileext*, (fp)->_ext._base)
151 
152 #define _UB(fp) _EXT(fp)->_ub
153 #define _FLOCK(fp)  _EXT(fp)->_lock
154 
155 #define _FILEEXT_INIT(fp) \
156 do { \
157 	_UB(fp)._base = NULL; \
158 	_UB(fp)._size = 0; \
159 	WCIO_INIT(fp); \
160 	pthread_mutexattr_t attr; \
161 	pthread_mutexattr_init(&attr); \
162 	pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE); \
163 	pthread_mutex_init(&_FLOCK(fp), &attr); \
164 	pthread_mutexattr_destroy(&attr); \
165 	_EXT(fp)->_caller_handles_locking = false; \
166 } while (0)
167 
168 #define _FILEEXT_SETUP(f, fext) \
169 do { \
170 	(f)->_ext._base = __BIONIC_CAST(reinterpret_cast, unsigned char*, fext); \
171 	_FILEEXT_INIT(f); \
172 } while (0)
173 
174 /*
175  * Android <= KitKat had getc/putc macros in <stdio.h> that referred
176  * to __srget/__swbuf, so those symbols need to be public for LP32
177  * but can be hidden for LP64.
178  */
179 __LIBC32_LEGACY_PUBLIC__ int __srget(FILE*);
180 __LIBC32_LEGACY_PUBLIC__ int __swbuf(int, FILE*);
181 __LIBC32_LEGACY_PUBLIC__ int __srefill(FILE*);
182 
183 /* This was referenced by the apportable middleware for LP32. */
184 __LIBC32_LEGACY_PUBLIC__ int __swsetup(FILE*);
185 
186 /* These were referenced by a couple of different pieces of middleware and the Crystax NDK. */
187 __LIBC32_LEGACY_PUBLIC__ int __sflags(const char*, int*);
188 __LIBC32_LEGACY_PUBLIC__ FILE* __sfp(void);
189 __LIBC32_LEGACY_PUBLIC__ void __smakebuf(FILE*);
190 
191 /* These are referenced by the Greed for Glory franchise. */
192 __LIBC32_LEGACY_PUBLIC__ int __sflush(FILE *);
193 __LIBC32_LEGACY_PUBLIC__ int __sread(void *, char *, int);
194 __LIBC32_LEGACY_PUBLIC__ int __swrite(void *, const char *, int);
195 __LIBC32_LEGACY_PUBLIC__ fpos_t __sseek(void *, fpos_t, int);
196 __LIBC32_LEGACY_PUBLIC__ int __sclose(void *);
197 __LIBC32_LEGACY_PUBLIC__ int _fwalk(int (*)(FILE *));
198 
199 off64_t __sseek64(void*, off64_t, int);
200 int	__sflush_locked(FILE *);
201 int	__swhatbuf(FILE *, size_t *, int *);
202 wint_t __fgetwc_unlock(FILE *);
203 wint_t	__ungetwc(wint_t, FILE *);
204 int	__vfprintf(FILE *, const char *, __va_list);
205 int	__svfscanf(FILE * __restrict, const char * __restrict, __va_list);
206 int	__vfwprintf(FILE * __restrict, const wchar_t * __restrict, __va_list);
207 int	__vfwscanf(FILE * __restrict, const wchar_t * __restrict, __va_list);
208 
209 /*
210  * Return true if the given FILE cannot be written now.
211  */
212 #define	cantwrite(fp) \
213 	((((fp)->_flags & __SWR) == 0 || (fp)->_bf._base == NULL) && \
214 	 __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 	if (_UB(fp)._base != (fp)->_ubuf) \
223 		free(_UB(fp)._base); \
224 	_UB(fp)._base = NULL; \
225 }
226 
227 /*
228  * test for an fgetln() buffer.
229  */
230 #define	HASLB(fp) ((fp)->_lb._base != NULL)
231 #define	FREELB(fp) { \
232 	free((char *)(fp)->_lb._base); \
233 	(fp)->_lb._base = NULL; \
234 }
235 
236 #define FLOCKFILE(fp)   if (!_EXT(fp)->_caller_handles_locking) flockfile(fp)
237 #define FUNLOCKFILE(fp) if (!_EXT(fp)->_caller_handles_locking) funlockfile(fp)
238 
239 #define FLOATING_POINT
240 #define PRINTF_WIDE_CHAR
241 #define SCANF_WIDE_CHAR
242 #define NO_PRINTF_PERCENT_N
243 
244 /* OpenBSD exposes these in <stdio.h>, but we only want them exposed to the implementation. */
245 #define __sferror(p)   (((p)->_flags & __SERR) != 0)
246 #define __sclearerr(p) ((void)((p)->_flags &= ~(__SERR|__SEOF)))
247 #define __sgetc(p) (--(p)->_r < 0 ? __srget(p) : (int)(*(p)->_p++))
248 
249 /* OpenBSD declares these in fvwrite.h but we want to ensure they're hidden. */
250 struct __suio;
251 extern 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 __END_DECLS
262 
263 #endif
264