xref: /titanic_50/usr/src/cmd/sendmail/include/sm/io.h (revision 711890bc9379ceea66272dc8d4981812224ea86e)
1 /*
2  * Copyright (c) 2000-2002, 2004 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 1.24 2004/03/03 19:14:49 ca Exp $
15  */
16 
17 #pragma ident	"%Z%%M%	%I%	%E% SMI"
18 
19 /*-
20  *	@(#)stdio.h	5.17 (Berkeley) 6/3/91
21  */
22 
23 #ifndef	SM_IO_H
24 #define SM_IO_H
25 
26 #include <stdio.h>
27 #include <sm/gen.h>
28 #include <sm/varargs.h>
29 
30 /* mode for sm io (exposed) */
31 #define SM_IO_RDWR	1	/* read-write */
32 #define SM_IO_RDONLY	2	/* read-only */
33 #define SM_IO_WRONLY	3	/* write-only */
34 #define SM_IO_APPEND	4	/* write-only from eof */
35 #define SM_IO_APPENDRW	5	/* read-write from eof */
36 #define SM_IO_RDWRTR	6	/* read-write with truncation indicated */
37 
38 # define SM_IO_BINARY	0x0	/* binary mode: not used in Unix */
39 #define SM_IS_BINARY(mode)	(((mode) & SM_IO_BINARY) != 0)
40 #define SM_IO_MODE(mode)	((mode) & 0x0f)
41 
42 #define SM_IO_RDWR_B	(SM_IO_RDWR|SM_IO_BINARY)
43 #define SM_IO_RDONLY_B	(SM_IO_RDONLY|SM_IO_BINARY)
44 #define SM_IO_WRONLY_B	(SM_IO_WRONLY|SM_IO_BINARY)
45 #define SM_IO_APPEND_B	(SM_IO_APPEND|SM_IO_BINARY)
46 #define SM_IO_APPENDRW_B	(SM_IO_APPENDRW|SM_IO_BINARY)
47 #define SM_IO_RDWRTR_B	(SM_IO_RDWRTR|SM_IO_BINARY)
48 
49 /* for sm_io_fseek, et al api's (exposed) */
50 #define SM_IO_SEEK_SET	0
51 #define SM_IO_SEEK_CUR	1
52 #define SM_IO_SEEK_END	2
53 
54 /* flags for info what's with different types (exposed) */
55 #define SM_IO_WHAT_MODE		1
56 #define SM_IO_WHAT_VECTORS	2
57 #define SM_IO_WHAT_FD		3
58 #define SM_IO_WHAT_TYPE		4
59 #define SM_IO_WHAT_ISTYPE	5
60 #define SM_IO_IS_READABLE	6
61 #define SM_IO_WHAT_TIMEOUT	7
62 #define SM_IO_WHAT_SIZE		8
63 
64 /* info flags (exposed) */
65 #define SM_IO_FTYPE_CREATE	1
66 #define SM_IO_FTYPE_MODIFY	2
67 #define SM_IO_FTYPE_DELETE	3
68 
69 #define SM_IO_SL_PRIO		1
70 
71 #define SM_IO_OPEN_MAX		20
72 
73 /* for internal buffers */
74 struct smbuf
75 {
76 	unsigned char	*smb_base;
77 	int		smb_size;
78 };
79 
80 /*
81 **  sm I/O state variables (internal only).
82 **
83 **	The following always hold:
84 **
85 **		if (flags&(SMLBF|SMWR)) == (SMLBF|SMWR),
86 **			lbfsize is -bf.size, else lbfsize is 0
87 **		if flags&SMRD, w is 0
88 **		if flags&SMWR, r is 0
89 **
90 **	This ensures that the getc and putc macros (or inline functions) never
91 **	try to write or read from a file that is in `read' or `write' mode.
92 **	(Moreover, they can, and do, automatically switch from read mode to
93 **	write mode, and back, on "r+" and "w+" files.)
94 **
95 **	lbfsize is used only to make the inline line-buffered output stream
96 **	code as compact as possible.
97 **
98 **	ub, up, and ur are used when ungetc() pushes back more characters
99 **	than fit in the current bf, or when ungetc() pushes back a character
100 **	that does not match the previous one in bf.  When this happens,
101 **	ub.base becomes non-nil (i.e., a stream has ungetc() data iff
102 **	ub.base!=NULL) and up and ur save the current values of p and r.
103 */
104 
105 typedef struct sm_file SM_FILE_T;
106 
107 struct sm_file
108 {
109 	const char	*sm_magic;	/* This SM_FILE_T is free when NULL */
110 	unsigned char	*f_p;		/* current position in (some) buffer */
111 	int		f_r;		/* read space left for getc() */
112 	int		f_w;		/* write space left for putc() */
113 	long		f_flags;	/* flags, below */
114 	short		f_file;		/* fileno, if Unix fd, else -1 */
115 	struct smbuf	f_bf;		/* the buffer (>= 1 byte, if !NULL) */
116 	int		f_lbfsize;	/* 0 or -bf.size, for inline putc */
117 
118 	/* These can be used for any purpose by a file type implementation: */
119 	void		*f_cookie;
120 	int		f_ival;
121 
122 	/* operations */
123 	int		(*f_close) __P((SM_FILE_T *));
124 	ssize_t		(*f_read)  __P((SM_FILE_T *, char *, size_t));
125 	off_t		(*f_seek)  __P((SM_FILE_T *, off_t, int));
126 	ssize_t		(*f_write) __P((SM_FILE_T *, const char *, size_t));
127 	int		(*f_open) __P((SM_FILE_T *, const void *, int,
128 					const void *));
129 	int		(*f_setinfo) __P((SM_FILE_T *, int , void *));
130 	int		(*f_getinfo) __P((SM_FILE_T *, int , void *));
131 	int		f_timeout;
132 	int		f_timeoutstate;   /* either blocking or non-blocking */
133 	char		*f_type;	/* for by-type lookups */
134 	struct sm_file	*f_flushfp;	/* flush this before reading parent */
135 	struct sm_file	*f_modefp;	/* sync mode with this fp */
136 
137 	/* separate buffer for long sequences of ungetc() */
138 	struct smbuf	f_ub;	/* ungetc buffer */
139 	unsigned char	*f_up;	/* saved f_p when f_p is doing ungetc */
140 	int		f_ur;	/* saved f_r when f_r is counting ungetc */
141 
142 	/* tricks to meet minimum requirements even when malloc() fails */
143 	unsigned char	f_ubuf[3];	/* guarantee an ungetc() buffer */
144 	unsigned char	f_nbuf[1];	/* guarantee a getc() buffer */
145 
146 	/* Unix stdio files get aligned to block boundaries on fseek() */
147 	int		f_blksize;	/* stat.st_blksize (may be != bf.size) */
148 	off_t		f_lseekoff;	/* current lseek offset */
149 	int		f_dup_cnt;	/* count file dup'd */
150 };
151 
152 __BEGIN_DECLS
153 extern SM_FILE_T	SmIoF[];
154 extern const char	SmFileMagic[];
155 extern SM_FILE_T	SmFtStdio_def;
156 extern SM_FILE_T	SmFtStdiofd_def;
157 extern SM_FILE_T	SmFtString_def;
158 extern SM_FILE_T	SmFtSyslog_def;
159 extern SM_FILE_T	SmFtRealStdio_def;
160 
161 #define SMIOIN_FILENO		0
162 #define SMIOOUT_FILENO		1
163 #define SMIOERR_FILENO		2
164 #define SMIOSTDIN_FILENO	3
165 #define SMIOSTDOUT_FILENO	4
166 #define SMIOSTDERR_FILENO	5
167 
168 /* Common predefined and already (usually) open files (exposed) */
169 #define smioin		(&SmIoF[SMIOIN_FILENO])
170 #define smioout		(&SmIoF[SMIOOUT_FILENO])
171 #define smioerr		(&SmIoF[SMIOERR_FILENO])
172 #define smiostdin	(&SmIoF[SMIOSTDIN_FILENO])
173 #define smiostdout	(&SmIoF[SMIOSTDOUT_FILENO])
174 #define smiostderr	(&SmIoF[SMIOSTDERR_FILENO])
175 
176 #define SmFtStdio	(&SmFtStdio_def)
177 #define SmFtStdiofd	(&SmFtStdiofd_def)
178 #define SmFtString	(&SmFtString_def)
179 #define SmFtSyslog	(&SmFtSyslog_def)
180 #define SmFtRealStdio	(&SmFtRealStdio_def)
181 
182 #ifdef __STDC__
183 # define SM_IO_SET_TYPE(f, name, open, close, read, write, seek, get, set, timeout) \
184     (f) = {SmFileMagic, (unsigned char *) 0, 0, 0, 0L, -1, {0}, 0, (void *) 0,\
185 	0, (close), (read), (seek), (write), (open), (set), (get), (timeout),\
186 	0, (name)}
187 # define SM_IO_INIT_TYPE(f, name, open, close, read, write, seek, get, set, timeout)
188 
189 #else /* __STDC__ */
190 # define SM_IO_SET_TYPE(f, name, open, close, read, write, seek, get, set, timeout) (f)
191 # define SM_IO_INIT_TYPE(f, name, open, close, read, write, seek, get, set, timeout) \
192 	(f).sm_magic = SmFileMagic;	\
193 	(f).f_p = (unsigned char *) 0;	\
194 	(f).f_r = 0;	\
195 	(f).f_w = 0;	\
196 	(f).f_flags = 0L;	\
197 	(f).f_file = 0;	\
198 	(f).f_bf.smb_base = (unsigned char *) 0;	\
199 	(f).f_bf.smb_size = 0;	\
200 	(f).f_lbfsize = 0;	\
201 	(f).f_cookie = (void *) 0;	\
202 	(f).f_ival = 0;	\
203 	(f).f_close = (close);	\
204 	(f).f_read = (read);	\
205 	(f).f_seek = (seek);	\
206 	(f).f_write = (write);	\
207 	(f).f_open = (open);	\
208 	(f).f_setinfo = (set);	\
209 	(f).f_getinfo = (get);	\
210 	(f).f_timeout = (timeout);	\
211 	(f).f_timeoutstate = 0;	\
212 	(f).f_type = (name);
213 
214 #endif /* __STDC__ */
215 
216 __END_DECLS
217 
218 /* Internal flags */
219 #define SMFBF		0x000001	/* XXXX fully buffered */
220 #define SMLBF		0x000002	/* line buffered */
221 #define SMNBF		0x000004	/* unbuffered */
222 #define SMNOW		0x000008	/* Flush each write; take read now */
223 #define SMRD		0x000010	/* OK to read */
224 #define SMWR		0x000020	/* OK to write */
225 	/* RD and WR are never simultaneously asserted */
226 #define SMRW		0x000040	/* open for reading & writing */
227 #define SMFEOF		0x000080	/* found EOF */
228 #define SMERR		0x000100	/* found error */
229 #define SMMBF		0x000200	/* buf is from malloc */
230 #define SMAPP		0x000400	/* fdopen()ed in append mode */
231 #define SMSTR		0x000800	/* this is an snprintf string */
232 #define SMOPT		0x001000	/* do fseek() optimisation */
233 #define SMNPT		0x002000	/* do not do fseek() optimisation */
234 #define SMOFF		0x004000	/* set iff offset is in fact correct */
235 #define SMALC		0x010000	/* allocate string space dynamically */
236 
237 #define SMMODEMASK	0x0070	/* read/write mode */
238 
239 /* defines for timeout constants */
240 #define SM_TIME_IMMEDIATE	(0)
241 #define SM_TIME_FOREVER		(-1)
242 #define SM_TIME_DEFAULT		(-2)
243 
244 /* timeout state for blocking */
245 #define SM_TIME_BLOCK		(0)	/* XXX just bool? */
246 #define SM_TIME_NONBLOCK	(1)
247 
248 /* Exposed buffering type flags */
249 #define SM_IO_FBF	0	/* setvbuf should set fully buffered */
250 #define SM_IO_LBF	1	/* setvbuf should set line buffered */
251 #define SM_IO_NBF	2	/* setvbuf should set unbuffered */
252 
253 /* setvbuf buffered, but through at lower file type layers */
254 #define SM_IO_NOW	3
255 
256 /*
257 **  size of buffer used by setbuf.
258 **  If underlying filesystem blocksize is discoverable that is used instead
259 */
260 
261 #define SM_IO_BUFSIZ	4096
262 
263 #define SM_IO_EOF	(-1)
264 
265 /* Functions defined in ANSI C standard.  */
266 __BEGIN_DECLS
267 SM_FILE_T *sm_io_autoflush __P((SM_FILE_T *, SM_FILE_T *));
268 void	 sm_io_automode __P((SM_FILE_T *, SM_FILE_T *));
269 void	 sm_io_clearerr __P((SM_FILE_T *));
270 int	 sm_io_close __P((SM_FILE_T *, int SM_NONVOLATILE));
271 SM_FILE_T *sm_io_dup __P((SM_FILE_T *));
272 int	 sm_io_eof __P((SM_FILE_T *));
273 int	 sm_io_error __P((SM_FILE_T *));
274 char	*sm_io_fgets __P((SM_FILE_T *, int, char *, int));
275 int	 sm_io_flush __P((SM_FILE_T *, int SM_NONVOLATILE));
276 
277 int PRINTFLIKE(3, 4)
278 sm_io_fprintf __P((SM_FILE_T *, int, const char *, ...));
279 
280 int	 sm_io_fputs __P((SM_FILE_T *, int, const char *));
281 
282 int SCANFLIKE(3, 4)
283 sm_io_fscanf __P((SM_FILE_T *, int, const char *, ...));
284 
285 int	 sm_io_getc __P((SM_FILE_T *, int));
286 int	 sm_io_getinfo __P((SM_FILE_T *, int, void *));
287 SM_FILE_T *sm_io_open __P((const SM_FILE_T *, int SM_NONVOLATILE, const void *,
288 			   int, const void *));
289 int	 sm_io_purge __P((SM_FILE_T *));
290 int	 sm_io_putc __P((SM_FILE_T *, int, int));
291 size_t	 sm_io_read __P((SM_FILE_T *, int, void *, size_t));
292 SM_FILE_T *sm_io_reopen __P((const SM_FILE_T *, int SM_NONVOLATILE,
293 			     const void *, int, const void *, SM_FILE_T *));
294 void	 sm_io_rewind __P((SM_FILE_T *, int));
295 int	 sm_io_seek __P((SM_FILE_T *, int SM_NONVOLATILE, long SM_NONVOLATILE,
296 			 int SM_NONVOLATILE));
297 int	 sm_io_setinfo __P((SM_FILE_T *, int, void *));
298 int	 sm_io_setvbuf __P((SM_FILE_T *, int, char *, int, size_t));
299 
300 int SCANFLIKE(2, 3)
301 sm_io_sscanf __P((const char *, char const *, ...));
302 
303 long	 sm_io_tell __P((SM_FILE_T *, int SM_NONVOLATILE));
304 int	 sm_io_ungetc __P((SM_FILE_T *, int, int));
305 int	 sm_io_vfprintf __P((SM_FILE_T *, int, const char *, va_list));
306 size_t	 sm_io_write __P((SM_FILE_T *, int, const void *, size_t));
307 
308 void	 sm_strio_init __P((SM_FILE_T *, char *, size_t));
309 
310 extern SM_FILE_T *
311 sm_io_fopen __P((
312 	char *_pathname,
313 	int _flags,
314 	...));
315 
316 extern SM_FILE_T *
317 sm_io_stdioopen __P((
318 	FILE *_stream,
319 	char *_mode));
320 
321 extern int
322 sm_vasprintf __P((
323 	char **_str,
324 	const char *_fmt,
325 	va_list _ap));
326 
327 extern int
328 sm_vsnprintf __P((
329 	char *,
330 	size_t,
331 	const char *,
332 	va_list));
333 
334 extern void
335 sm_perror __P((
336 	const char *));
337 
338 __END_DECLS
339 
340 /*
341 ** Functions internal to the implementation.
342 */
343 
344 __BEGIN_DECLS
345 int	sm_rget __P((SM_FILE_T *, int));
346 int	sm_vfscanf __P((SM_FILE_T *, int SM_NONVOLATILE, const char *,
347 			va_list SM_NONVOLATILE));
348 int	sm_wbuf __P((SM_FILE_T *, int, int));
349 __END_DECLS
350 
351 /*
352 **  The macros are here so that we can
353 **  define function versions in the library.
354 */
355 
356 #define sm_getc(f, t) \
357 	(--(f)->f_r < 0 ? \
358 		sm_rget(f, t) : \
359 		(int)(*(f)->f_p++))
360 
361 /*
362 **  This has been tuned to generate reasonable code on the vax using pcc.
363 **  (It also generates reasonable x86 code using gcc.)
364 */
365 
366 #define sm_putc(f, t, c) \
367 	(--(f)->f_w < 0 ? \
368 		(f)->f_w >= (f)->f_lbfsize ? \
369 			(*(f)->f_p = (c)), *(f)->f_p != '\n' ? \
370 				(int)*(f)->f_p++ : \
371 				sm_wbuf(f, t, '\n') : \
372 			sm_wbuf(f, t, (int)(c)) : \
373 		(*(f)->f_p = (c), (int)*(f)->f_p++))
374 
375 #define sm_eof(p)	(((p)->f_flags & SMFEOF) != 0)
376 #define sm_error(p)	(((p)->f_flags & SMERR) != 0)
377 #define sm_clearerr(p)	((void)((p)->f_flags &= ~(SMERR|SMFEOF)))
378 
379 #define sm_io_eof(p)	sm_eof(p)
380 #define sm_io_error(p)	sm_error(p)
381 
382 #define sm_io_clearerr(p)	sm_clearerr(p)
383 
384 #ifndef lint
385 # ifndef _POSIX_SOURCE
386 #  define sm_io_getc(fp, t)	sm_getc(fp, t)
387 #  define sm_io_putc(fp, t, x)	sm_putc(fp, t, x)
388 # endif /* _POSIX_SOURCE */
389 #endif /* lint */
390 
391 #endif /* SM_IO_H */
392