xref: /freebsd/contrib/sendmail/include/sm/io.h (revision 94c01205742119acdf56dbbd22fc274e5e38cfd4)
1 /*
2  * Copyright (c) 2000-2002 Sendmail, Inc. and its suppliers.
3  *      All rights reserved.
4  * Copyright (c) 1990
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  * By using this file, you agree to the terms and conditions set
11  * forth in the LICENSE file which can be found at the top level of
12  * the sendmail distribution.
13  *
14  *	$Id: io.h,v 1.23 2002/02/23 19:32:17 gshapiro Exp $
15  */
16 
17 /*-
18  *	@(#)stdio.h	5.17 (Berkeley) 6/3/91
19  */
20 
21 #ifndef	SM_IO_H
22 #define SM_IO_H
23 
24 #include <stdio.h>
25 #include <sm/gen.h>
26 #include <sm/varargs.h>
27 
28 /* mode for sm io (exposed) */
29 #define SM_IO_RDWR	1	/* read-write */
30 #define SM_IO_RDONLY	2	/* read-only */
31 #define SM_IO_WRONLY	3	/* write-only */
32 #define SM_IO_APPEND	4	/* write-only from eof */
33 #define SM_IO_APPENDRW	5	/* read-write from eof */
34 #define SM_IO_RDWRTR	6	/* read-write with truncation indicated */
35 
36 /* for sm_io_fseek, et al api's (exposed) */
37 #define SM_IO_SEEK_SET	0
38 #define SM_IO_SEEK_CUR	1
39 #define SM_IO_SEEK_END	2
40 
41 /* flags for info what's with different types (exposed) */
42 #define SM_IO_WHAT_MODE		1
43 #define SM_IO_WHAT_VECTORS	2
44 #define SM_IO_WHAT_FD		3
45 #define SM_IO_WHAT_TYPE		4
46 #define SM_IO_WHAT_ISTYPE	5
47 #define SM_IO_IS_READABLE	6
48 #define SM_IO_WHAT_TIMEOUT	7
49 #define SM_IO_WHAT_SIZE		8
50 
51 /* info flags (exposed) */
52 #define SM_IO_FTYPE_CREATE	1
53 #define SM_IO_FTYPE_MODIFY	2
54 #define SM_IO_FTYPE_DELETE	3
55 
56 #define SM_IO_SL_PRIO		1
57 
58 #define SM_IO_OPEN_MAX		20
59 
60 /* for internal buffers */
61 struct smbuf
62 {
63 	unsigned char	*smb_base;
64 	int		smb_size;
65 };
66 
67 /*
68 **  sm I/O state variables (internal only).
69 **
70 **	The following always hold:
71 **
72 **		if (flags&(SMLBF|SMWR)) == (SMLBF|SMWR),
73 **			lbfsize is -bf.size, else lbfsize is 0
74 **		if flags&SMRD, w is 0
75 **		if flags&SMWR, r is 0
76 **
77 **	This ensures that the getc and putc macros (or inline functions) never
78 **	try to write or read from a file that is in `read' or `write' mode.
79 **	(Moreover, they can, and do, automatically switch from read mode to
80 **	write mode, and back, on "r+" and "w+" files.)
81 **
82 **	lbfsize is used only to make the inline line-buffered output stream
83 **	code as compact as possible.
84 **
85 **	ub, up, and ur are used when ungetc() pushes back more characters
86 **	than fit in the current bf, or when ungetc() pushes back a character
87 **	that does not match the previous one in bf.  When this happens,
88 **	ub.base becomes non-nil (i.e., a stream has ungetc() data iff
89 **	ub.base!=NULL) and up and ur save the current values of p and r.
90 */
91 
92 typedef struct sm_file SM_FILE_T;
93 
94 struct sm_file
95 {
96 	const char	*sm_magic;	/* This SM_FILE_T is free when NULL */
97 	unsigned char	*f_p;		/* current position in (some) buffer */
98 	int		f_r;		/* read space left for getc() */
99 	int		f_w;		/* write space left for putc() */
100 	long		f_flags;	/* flags, below */
101 	short		f_file;		/* fileno, if Unix fd, else -1 */
102 	struct smbuf	f_bf;		/* the buffer (>= 1 byte, if !NULL) */
103 	int		f_lbfsize;	/* 0 or -bf.size, for inline putc */
104 
105 	/* These can be used for any purpose by a file type implementation: */
106 	void		*f_cookie;
107 	int		f_ival;
108 
109 	/* operations */
110 	int		(*f_close) __P((SM_FILE_T *));
111 	ssize_t		(*f_read)  __P((SM_FILE_T *, char *, size_t));
112 	off_t		(*f_seek)  __P((SM_FILE_T *, off_t, int));
113 	ssize_t		(*f_write) __P((SM_FILE_T *, const char *, size_t));
114 	int		(*f_open) __P((SM_FILE_T *, const void *, int,
115 					const void *));
116 	int		(*f_setinfo) __P((SM_FILE_T *, int , void *));
117 	int		(*f_getinfo) __P((SM_FILE_T *, int , void *));
118 	int		f_timeout;
119 	int		f_timeoutstate;   /* either blocking or non-blocking */
120 	char		*f_type;	/* for by-type lookups */
121 	struct sm_file	*f_flushfp;	/* flush this before reading parent */
122 	struct sm_file	*f_modefp;	/* sync mode with this fp */
123 
124 	/* separate buffer for long sequences of ungetc() */
125 	struct smbuf	f_ub;	/* ungetc buffer */
126 	unsigned char	*f_up;	/* saved f_p when f_p is doing ungetc */
127 	int		f_ur;	/* saved f_r when f_r is counting ungetc */
128 
129 	/* tricks to meet minimum requirements even when malloc() fails */
130 	unsigned char	f_ubuf[3];	/* guarantee an ungetc() buffer */
131 	unsigned char	f_nbuf[1];	/* guarantee a getc() buffer */
132 
133 	/* Unix stdio files get aligned to block boundaries on fseek() */
134 	int		f_blksize;	/* stat.st_blksize (may be != bf.size) */
135 	off_t		f_lseekoff;	/* current lseek offset */
136 	int		f_dup_cnt;	/* count file dup'd */
137 };
138 
139 __BEGIN_DECLS
140 extern SM_FILE_T	SmIoF[];
141 extern const char	SmFileMagic[];
142 extern SM_FILE_T	SmFtStdio_def;
143 extern SM_FILE_T	SmFtStdiofd_def;
144 extern SM_FILE_T	SmFtString_def;
145 extern SM_FILE_T	SmFtSyslog_def;
146 extern SM_FILE_T	SmFtRealStdio_def;
147 
148 #define SMIOIN_FILENO		0
149 #define SMIOOUT_FILENO		1
150 #define SMIOERR_FILENO		2
151 #define SMIOSTDIN_FILENO	3
152 #define SMIOSTDOUT_FILENO	4
153 #define SMIOSTDERR_FILENO	5
154 
155 /* Common predefined and already (usually) open files (exposed) */
156 #define smioin		(&SmIoF[SMIOIN_FILENO])
157 #define smioout		(&SmIoF[SMIOOUT_FILENO])
158 #define smioerr		(&SmIoF[SMIOERR_FILENO])
159 #define smiostdin	(&SmIoF[SMIOSTDIN_FILENO])
160 #define smiostdout	(&SmIoF[SMIOSTDOUT_FILENO])
161 #define smiostderr	(&SmIoF[SMIOSTDERR_FILENO])
162 
163 #define SmFtStdio	(&SmFtStdio_def)
164 #define SmFtStdiofd	(&SmFtStdiofd_def)
165 #define SmFtString	(&SmFtString_def)
166 #define SmFtSyslog	(&SmFtSyslog_def)
167 #define SmFtRealStdio	(&SmFtRealStdio_def)
168 
169 #ifdef __STDC__
170 # define SM_IO_SET_TYPE(f, name, open, close, read, write, seek, get, set, timeout) \
171     (f) = {SmFileMagic, (unsigned char *) 0, 0, 0, 0L, -1, {0}, 0, (void *) 0,\
172 	0, (close), (read), (seek), (write), (open), (set), (get), (timeout),\
173 	0, (name)}
174 # define SM_IO_INIT_TYPE(f, name, open, close, read, write, seek, get, set, timeout)
175 
176 #else /* __STDC__ */
177 # define SM_IO_SET_TYPE(f, name, open, close, read, write, seek, get, set, timeout) (f)
178 # define SM_IO_INIT_TYPE(f, name, open, close, read, write, seek, get, set, timeout) \
179 	(f).sm_magic = SmFileMagic;	\
180 	(f).f_p = (unsigned char *) 0;	\
181 	(f).f_r = 0;	\
182 	(f).f_w = 0;	\
183 	(f).f_flags = 0L;	\
184 	(f).f_file = 0;	\
185 	(f).f_bf.smb_base = (unsigned char *) 0;	\
186 	(f).f_bf.smb_size = 0;	\
187 	(f).f_lbfsize = 0;	\
188 	(f).f_cookie = (void *) 0;	\
189 	(f).f_ival = 0;	\
190 	(f).f_close = (close);	\
191 	(f).f_read = (read);	\
192 	(f).f_seek = (seek);	\
193 	(f).f_write = (write);	\
194 	(f).f_open = (open);	\
195 	(f).f_setinfo = (set);	\
196 	(f).f_getinfo = (get);	\
197 	(f).f_timeout = (timeout);	\
198 	(f).f_timeoutstate = 0;	\
199 	(f).f_type = (name);
200 
201 #endif /* __STDC__ */
202 
203 __END_DECLS
204 
205 /* Internal flags */
206 #define SMFBF		0x000001	/* XXXX fully buffered */
207 #define SMLBF		0x000002	/* line buffered */
208 #define SMNBF		0x000004	/* unbuffered */
209 #define SMNOW		0x000008	/* Flush each write; take read now */
210 #define SMRD		0x000010	/* OK to read */
211 #define SMWR		0x000020	/* OK to write */
212 	/* RD and WR are never simultaneously asserted */
213 #define SMRW		0x000040	/* open for reading & writing */
214 #define SMFEOF		0x000080	/* found EOF */
215 #define SMERR		0x000100	/* found error */
216 #define SMMBF		0x000200	/* buf is from malloc */
217 #define SMAPP		0x000400	/* fdopen()ed in append mode */
218 #define SMSTR		0x000800	/* this is an snprintf string */
219 #define SMOPT		0x001000	/* do fseek() optimisation */
220 #define SMNPT		0x002000	/* do not do fseek() optimisation */
221 #define SMOFF		0x004000	/* set iff offset is in fact correct */
222 #define SMALC		0x010000	/* allocate string space dynamically */
223 
224 #define SMMODEMASK	0x0070	/* read/write mode */
225 
226 /* defines for timeout constants */
227 #define SM_TIME_IMMEDIATE	(0)
228 #define SM_TIME_FOREVER		(-1)
229 #define SM_TIME_DEFAULT		(-2)
230 
231 /* timeout state for blocking */
232 #define SM_TIME_BLOCK		(0)	/* XXX just bool? */
233 #define SM_TIME_NONBLOCK	(1)
234 
235 /* Exposed buffering type flags */
236 #define SM_IO_FBF	0	/* setvbuf should set fully buffered */
237 #define SM_IO_LBF	1	/* setvbuf should set line buffered */
238 #define SM_IO_NBF	2	/* setvbuf should set unbuffered */
239 
240 /* setvbuf buffered, but through at lower file type layers */
241 #define SM_IO_NOW	3
242 
243 /*
244 **  size of buffer used by setbuf.
245 **  If underlying filesystem blocksize is discoverable that is used instead
246 */
247 
248 #define SM_IO_BUFSIZ	4096
249 
250 #define SM_IO_EOF	(-1)
251 
252 /* Functions defined in ANSI C standard.  */
253 __BEGIN_DECLS
254 SM_FILE_T *sm_io_autoflush __P((SM_FILE_T *, SM_FILE_T *));
255 void	 sm_io_automode __P((SM_FILE_T *, SM_FILE_T *));
256 void	 sm_io_clearerr __P((SM_FILE_T *));
257 int	 sm_io_close __P((SM_FILE_T *, int SM_NONVOLATILE));
258 SM_FILE_T *sm_io_dup __P((SM_FILE_T *));
259 int	 sm_io_eof __P((SM_FILE_T *));
260 int	 sm_io_error __P((SM_FILE_T *));
261 char	*sm_io_fgets __P((SM_FILE_T *, int, char *, int));
262 int	 sm_io_flush __P((SM_FILE_T *, int SM_NONVOLATILE));
263 
264 int PRINTFLIKE(3, 4)
265 sm_io_fprintf __P((SM_FILE_T *, int, const char *, ...));
266 
267 int	 sm_io_fputs __P((SM_FILE_T *, int, const char *));
268 
269 int SCANFLIKE(3, 4)
270 sm_io_fscanf __P((SM_FILE_T *, int, const char *, ...));
271 
272 int	 sm_io_getc __P((SM_FILE_T *, int));
273 int	 sm_io_getinfo __P((SM_FILE_T *, int, void *));
274 SM_FILE_T *sm_io_open __P((const SM_FILE_T *, int SM_NONVOLATILE, const void *,
275 			   int, const void *));
276 int	 sm_io_purge __P((SM_FILE_T *));
277 int	 sm_io_putc __P((SM_FILE_T *, int, int));
278 size_t	 sm_io_read __P((SM_FILE_T *, int, void *, size_t));
279 SM_FILE_T *sm_io_reopen __P((const SM_FILE_T *, int SM_NONVOLATILE,
280 			     const void *, int, const void *, SM_FILE_T *));
281 void	 sm_io_rewind __P((SM_FILE_T *, int));
282 int	 sm_io_seek __P((SM_FILE_T *, int SM_NONVOLATILE, long SM_NONVOLATILE,
283 			 int SM_NONVOLATILE));
284 int	 sm_io_setinfo __P((SM_FILE_T *, int, void *));
285 int	 sm_io_setvbuf __P((SM_FILE_T *, int, char *, int, size_t));
286 
287 int SCANFLIKE(2, 3)
288 sm_io_sscanf __P((const char *, char const *, ...));
289 
290 long	 sm_io_tell __P((SM_FILE_T *, int SM_NONVOLATILE));
291 int	 sm_io_ungetc __P((SM_FILE_T *, int, int));
292 int	 sm_io_vfprintf __P((SM_FILE_T *, int, const char *, va_list));
293 size_t	 sm_io_write __P((SM_FILE_T *, int, const void *, size_t));
294 
295 void	 sm_strio_init __P((SM_FILE_T *, char *, size_t));
296 
297 extern SM_FILE_T *
298 sm_io_fopen __P((
299 	char *_pathname,
300 	int _flags,
301 	...));
302 
303 extern SM_FILE_T *
304 sm_io_stdioopen __P((
305 	FILE *_stream,
306 	char *_mode));
307 
308 extern int
309 sm_vasprintf __P((
310 	char **_str,
311 	const char *_fmt,
312 	va_list _ap));
313 
314 extern int
315 sm_vsnprintf __P((
316 	char *,
317 	size_t,
318 	const char *,
319 	va_list));
320 
321 extern void
322 sm_perror __P((
323 	const char *));
324 
325 __END_DECLS
326 
327 /*
328 ** Functions internal to the implementation.
329 */
330 
331 __BEGIN_DECLS
332 int	sm_rget __P((SM_FILE_T *, int));
333 int	sm_vfscanf __P((SM_FILE_T *, int SM_NONVOLATILE, const char *,
334 			va_list SM_NONVOLATILE));
335 int	sm_wbuf __P((SM_FILE_T *, int, int));
336 __END_DECLS
337 
338 /*
339 **  The macros are here so that we can
340 **  define function versions in the library.
341 */
342 
343 #define sm_getc(f, t) \
344 	(--(f)->f_r < 0 ? \
345 		sm_rget(f, t) : \
346 		(int)(*(f)->f_p++))
347 
348 /*
349 **  This has been tuned to generate reasonable code on the vax using pcc.
350 **  (It also generates reasonable x86 code using gcc.)
351 */
352 
353 #define sm_putc(f, t, c) \
354 	(--(f)->f_w < 0 ? \
355 		(f)->f_w >= (f)->f_lbfsize ? \
356 			(*(f)->f_p = (c)), *(f)->f_p != '\n' ? \
357 				(int)*(f)->f_p++ : \
358 				sm_wbuf(f, t, '\n') : \
359 			sm_wbuf(f, t, (int)(c)) : \
360 		(*(f)->f_p = (c), (int)*(f)->f_p++))
361 
362 #define sm_eof(p)	(((p)->f_flags & SMFEOF) != 0)
363 #define sm_error(p)	(((p)->f_flags & SMERR) != 0)
364 #define sm_clearerr(p)	((void)((p)->f_flags &= ~(SMERR|SMFEOF)))
365 
366 #define sm_io_eof(p)	sm_eof(p)
367 #define sm_io_error(p)	sm_error(p)
368 
369 #define sm_io_clearerr(p)	sm_clearerr(p)
370 
371 #ifndef lint
372 # ifndef _POSIX_SOURCE
373 #  define sm_io_getc(fp, t)	sm_getc(fp, t)
374 #  define sm_io_putc(fp, t, x)	sm_putc(fp, t, x)
375 # endif /* _POSIX_SOURCE */
376 #endif /* lint */
377 
378 #endif /* SM_IO_H */
379