xref: /illumos-gate/usr/src/cmd/sendmail/include/sm/io.h (revision 2a8bcb4e)
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 /*-
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 # define SM_IO_BINARY	0x0	/* binary mode: not used in Unix */
37 #define SM_IS_BINARY(mode)	(((mode) & SM_IO_BINARY) != 0)
38 #define SM_IO_MODE(mode)	((mode) & 0x0f)
39 
40 #define SM_IO_RDWR_B	(SM_IO_RDWR|SM_IO_BINARY)
41 #define SM_IO_RDONLY_B	(SM_IO_RDONLY|SM_IO_BINARY)
42 #define SM_IO_WRONLY_B	(SM_IO_WRONLY|SM_IO_BINARY)
43 #define SM_IO_APPEND_B	(SM_IO_APPEND|SM_IO_BINARY)
44 #define SM_IO_APPENDRW_B	(SM_IO_APPENDRW|SM_IO_BINARY)
45 #define SM_IO_RDWRTR_B	(SM_IO_RDWRTR|SM_IO_BINARY)
46 
47 /* for sm_io_fseek, et al api's (exposed) */
48 #define SM_IO_SEEK_SET	0
49 #define SM_IO_SEEK_CUR	1
50 #define SM_IO_SEEK_END	2
51 
52 /* flags for info what's with different types (exposed) */
53 #define SM_IO_WHAT_MODE		1
54 #define SM_IO_WHAT_VECTORS	2
55 #define SM_IO_WHAT_FD		3
56 #define SM_IO_WHAT_TYPE		4
57 #define SM_IO_WHAT_ISTYPE	5
58 #define SM_IO_IS_READABLE	6
59 #define SM_IO_WHAT_TIMEOUT	7
60 #define SM_IO_WHAT_SIZE		8
61 
62 /* info flags (exposed) */
63 #define SM_IO_FTYPE_CREATE	1
64 #define SM_IO_FTYPE_MODIFY	2
65 #define SM_IO_FTYPE_DELETE	3
66 
67 #define SM_IO_SL_PRIO		1
68 
69 #define SM_IO_OPEN_MAX		20
70 
71 /* for internal buffers */
72 struct smbuf
73 {
74 	unsigned char	*smb_base;
75 	int		smb_size;
76 };
77 
78 /*
79 **  sm I/O state variables (internal only).
80 **
81 **	The following always hold:
82 **
83 **		if (flags&(SMLBF|SMWR)) == (SMLBF|SMWR),
84 **			lbfsize is -bf.size, else lbfsize is 0
85 **		if flags&SMRD, w is 0
86 **		if flags&SMWR, r is 0
87 **
88 **	This ensures that the getc and putc macros (or inline functions) never
89 **	try to write or read from a file that is in `read' or `write' mode.
90 **	(Moreover, they can, and do, automatically switch from read mode to
91 **	write mode, and back, on "r+" and "w+" files.)
92 **
93 **	lbfsize is used only to make the inline line-buffered output stream
94 **	code as compact as possible.
95 **
96 **	ub, up, and ur are used when ungetc() pushes back more characters
97 **	than fit in the current bf, or when ungetc() pushes back a character
98 **	that does not match the previous one in bf.  When this happens,
99 **	ub.base becomes non-nil (i.e., a stream has ungetc() data iff
100 **	ub.base!=NULL) and up and ur save the current values of p and r.
101 */
102 
103 typedef struct sm_file SM_FILE_T;
104 
105 struct sm_file
106 {
107 	const char	*sm_magic;	/* This SM_FILE_T is free when NULL */
108 	unsigned char	*f_p;		/* current position in (some) buffer */
109 	int		f_r;		/* read space left for getc() */
110 	int		f_w;		/* write space left for putc() */
111 	long		f_flags;	/* flags, below */
112 	short		f_file;		/* fileno, if Unix fd, else -1 */
113 	struct smbuf	f_bf;		/* the buffer (>= 1 byte, if !NULL) */
114 	int		f_lbfsize;	/* 0 or -bf.size, for inline putc */
115 
116 	/* These can be used for any purpose by a file type implementation: */
117 	void		*f_cookie;
118 	int		f_ival;
119 
120 	/* operations */
121 	int		(*f_close) __P((SM_FILE_T *));
122 	ssize_t		(*f_read)  __P((SM_FILE_T *, char *, size_t));
123 	off_t		(*f_seek)  __P((SM_FILE_T *, off_t, int));
124 	ssize_t		(*f_write) __P((SM_FILE_T *, const char *, size_t));
125 	int		(*f_open) __P((SM_FILE_T *, const void *, int,
126 					const void *));
127 	int		(*f_setinfo) __P((SM_FILE_T *, int , void *));
128 	int		(*f_getinfo) __P((SM_FILE_T *, int , void *));
129 	int		f_timeout;
130 	int		f_timeoutstate;   /* either blocking or non-blocking */
131 	char		*f_type;	/* for by-type lookups */
132 	struct sm_file	*f_flushfp;	/* flush this before reading parent */
133 	struct sm_file	*f_modefp;	/* sync mode with this fp */
134 
135 	/* separate buffer for long sequences of ungetc() */
136 	struct smbuf	f_ub;	/* ungetc buffer */
137 	unsigned char	*f_up;	/* saved f_p when f_p is doing ungetc */
138 	int		f_ur;	/* saved f_r when f_r is counting ungetc */
139 
140 	/* tricks to meet minimum requirements even when malloc() fails */
141 	unsigned char	f_ubuf[3];	/* guarantee an ungetc() buffer */
142 	unsigned char	f_nbuf[1];	/* guarantee a getc() buffer */
143 
144 	/* Unix stdio files get aligned to block boundaries on fseek() */
145 	int		f_blksize;	/* stat.st_blksize (may be != bf.size) */
146 	off_t		f_lseekoff;	/* current lseek offset */
147 	int		f_dup_cnt;	/* count file dup'd */
148 };
149 
150 __BEGIN_DECLS
151 extern SM_FILE_T	SmIoF[];
152 extern const char	SmFileMagic[];
153 extern SM_FILE_T	SmFtStdio_def;
154 extern SM_FILE_T	SmFtStdiofd_def;
155 extern SM_FILE_T	SmFtString_def;
156 extern SM_FILE_T	SmFtSyslog_def;
157 extern SM_FILE_T	SmFtRealStdio_def;
158 
159 #define SMIOIN_FILENO		0
160 #define SMIOOUT_FILENO		1
161 #define SMIOERR_FILENO		2
162 #define SMIOSTDIN_FILENO	3
163 #define SMIOSTDOUT_FILENO	4
164 #define SMIOSTDERR_FILENO	5
165 
166 /* Common predefined and already (usually) open files (exposed) */
167 #define smioin		(&SmIoF[SMIOIN_FILENO])
168 #define smioout		(&SmIoF[SMIOOUT_FILENO])
169 #define smioerr		(&SmIoF[SMIOERR_FILENO])
170 #define smiostdin	(&SmIoF[SMIOSTDIN_FILENO])
171 #define smiostdout	(&SmIoF[SMIOSTDOUT_FILENO])
172 #define smiostderr	(&SmIoF[SMIOSTDERR_FILENO])
173 
174 #define SmFtStdio	(&SmFtStdio_def)
175 #define SmFtStdiofd	(&SmFtStdiofd_def)
176 #define SmFtString	(&SmFtString_def)
177 #define SmFtSyslog	(&SmFtSyslog_def)
178 #define SmFtRealStdio	(&SmFtRealStdio_def)
179 
180 #ifdef __STDC__
181 # define SM_IO_SET_TYPE(f, name, open, close, read, write, seek, get, set, timeout) \
182     (f) = {SmFileMagic, (unsigned char *) 0, 0, 0, 0L, -1, {0}, 0, (void *) 0,\
183 	0, (close), (read), (seek), (write), (open), (set), (get), (timeout),\
184 	0, (name)}
185 # define SM_IO_INIT_TYPE(f, name, open, close, read, write, seek, get, set, timeout)
186 
187 #else /* __STDC__ */
188 # define SM_IO_SET_TYPE(f, name, open, close, read, write, seek, get, set, timeout) (f)
189 # define SM_IO_INIT_TYPE(f, name, open, close, read, write, seek, get, set, timeout) \
190 	(f).sm_magic = SmFileMagic;	\
191 	(f).f_p = (unsigned char *) 0;	\
192 	(f).f_r = 0;	\
193 	(f).f_w = 0;	\
194 	(f).f_flags = 0L;	\
195 	(f).f_file = 0;	\
196 	(f).f_bf.smb_base = (unsigned char *) 0;	\
197 	(f).f_bf.smb_size = 0;	\
198 	(f).f_lbfsize = 0;	\
199 	(f).f_cookie = (void *) 0;	\
200 	(f).f_ival = 0;	\
201 	(f).f_close = (close);	\
202 	(f).f_read = (read);	\
203 	(f).f_seek = (seek);	\
204 	(f).f_write = (write);	\
205 	(f).f_open = (open);	\
206 	(f).f_setinfo = (set);	\
207 	(f).f_getinfo = (get);	\
208 	(f).f_timeout = (timeout);	\
209 	(f).f_timeoutstate = 0;	\
210 	(f).f_type = (name);
211 
212 #endif /* __STDC__ */
213 
214 __END_DECLS
215 
216 /* Internal flags */
217 #define SMFBF		0x000001	/* XXXX fully buffered */
218 #define SMLBF		0x000002	/* line buffered */
219 #define SMNBF		0x000004	/* unbuffered */
220 #define SMNOW		0x000008	/* Flush each write; take read now */
221 #define SMRD		0x000010	/* OK to read */
222 #define SMWR		0x000020	/* OK to write */
223 	/* RD and WR are never simultaneously asserted */
224 #define SMRW		0x000040	/* open for reading & writing */
225 #define SMFEOF		0x000080	/* found EOF */
226 #define SMERR		0x000100	/* found error */
227 #define SMMBF		0x000200	/* buf is from malloc */
228 #define SMAPP		0x000400	/* fdopen()ed in append mode */
229 #define SMSTR		0x000800	/* this is an snprintf string */
230 #define SMOPT		0x001000	/* do fseek() optimisation */
231 #define SMNPT		0x002000	/* do not do fseek() optimisation */
232 #define SMOFF		0x004000	/* set iff offset is in fact correct */
233 #define SMALC		0x010000	/* allocate string space dynamically */
234 
235 #define SMMODEMASK	0x0070	/* read/write mode */
236 
237 /* defines for timeout constants */
238 #define SM_TIME_IMMEDIATE	(0)
239 #define SM_TIME_FOREVER		(-1)
240 #define SM_TIME_DEFAULT		(-2)
241 
242 /* timeout state for blocking */
243 #define SM_TIME_BLOCK		(0)	/* XXX just bool? */
244 #define SM_TIME_NONBLOCK	(1)
245 
246 /* Exposed buffering type flags */
247 #define SM_IO_FBF	0	/* setvbuf should set fully buffered */
248 #define SM_IO_LBF	1	/* setvbuf should set line buffered */
249 #define SM_IO_NBF	2	/* setvbuf should set unbuffered */
250 
251 /* setvbuf buffered, but through at lower file type layers */
252 #define SM_IO_NOW	3
253 
254 /*
255 **  size of buffer used by setbuf.
256 **  If underlying filesystem blocksize is discoverable that is used instead
257 */
258 
259 #define SM_IO_BUFSIZ	4096
260 
261 #define SM_IO_EOF	(-1)
262 
263 /* Functions defined in ANSI C standard.  */
264 __BEGIN_DECLS
265 SM_FILE_T *sm_io_autoflush __P((SM_FILE_T *, SM_FILE_T *));
266 void	 sm_io_automode __P((SM_FILE_T *, SM_FILE_T *));
267 void	 sm_io_clearerr __P((SM_FILE_T *));
268 int	 sm_io_close __P((SM_FILE_T *, int SM_NONVOLATILE));
269 SM_FILE_T *sm_io_dup __P((SM_FILE_T *));
270 int	 sm_io_eof __P((SM_FILE_T *));
271 int	 sm_io_error __P((SM_FILE_T *));
272 char	*sm_io_fgets __P((SM_FILE_T *, int, char *, int));
273 int	 sm_io_flush __P((SM_FILE_T *, int SM_NONVOLATILE));
274 
275 int PRINTFLIKE(3, 4)
276 sm_io_fprintf __P((SM_FILE_T *, int, const char *, ...));
277 
278 int	 sm_io_fputs __P((SM_FILE_T *, int, const char *));
279 
280 int SCANFLIKE(3, 4)
281 sm_io_fscanf __P((SM_FILE_T *, int, const char *, ...));
282 
283 int	 sm_io_getc __P((SM_FILE_T *, int));
284 int	 sm_io_getinfo __P((SM_FILE_T *, int, void *));
285 SM_FILE_T *sm_io_open __P((const SM_FILE_T *, int SM_NONVOLATILE, const void *,
286 			   int, const void *));
287 int	 sm_io_purge __P((SM_FILE_T *));
288 int	 sm_io_putc __P((SM_FILE_T *, int, int));
289 size_t	 sm_io_read __P((SM_FILE_T *, int, void *, size_t));
290 SM_FILE_T *sm_io_reopen __P((const SM_FILE_T *, int SM_NONVOLATILE,
291 			     const void *, int, const void *, SM_FILE_T *));
292 void	 sm_io_rewind __P((SM_FILE_T *, int));
293 int	 sm_io_seek __P((SM_FILE_T *, int SM_NONVOLATILE, long SM_NONVOLATILE,
294 			 int SM_NONVOLATILE));
295 int	 sm_io_setinfo __P((SM_FILE_T *, int, void *));
296 int	 sm_io_setvbuf __P((SM_FILE_T *, int, char *, int, size_t));
297 
298 int SCANFLIKE(2, 3)
299 sm_io_sscanf __P((const char *, char const *, ...));
300 
301 long	 sm_io_tell __P((SM_FILE_T *, int SM_NONVOLATILE));
302 int	 sm_io_ungetc __P((SM_FILE_T *, int, int));
303 int	 sm_io_vfprintf __P((SM_FILE_T *, int, const char *, va_list));
304 size_t	 sm_io_write __P((SM_FILE_T *, int, const void *, size_t));
305 
306 void	 sm_strio_init __P((SM_FILE_T *, char *, size_t));
307 
308 extern SM_FILE_T *
309 sm_io_fopen __P((
310 	char *_pathname,
311 	int _flags,
312 	...));
313 
314 extern SM_FILE_T *
315 sm_io_stdioopen __P((
316 	FILE *_stream,
317 	char *_mode));
318 
319 extern int
320 sm_vasprintf __P((
321 	char **_str,
322 	const char *_fmt,
323 	va_list _ap));
324 
325 extern int
326 sm_vsnprintf __P((
327 	char *,
328 	size_t,
329 	const char *,
330 	va_list));
331 
332 extern void
333 sm_perror __P((
334 	const char *));
335 
336 __END_DECLS
337 
338 /*
339 ** Functions internal to the implementation.
340 */
341 
342 __BEGIN_DECLS
343 int	sm_rget __P((SM_FILE_T *, int));
344 int	sm_vfscanf __P((SM_FILE_T *, int SM_NONVOLATILE, const char *,
345 			va_list SM_NONVOLATILE));
346 int	sm_wbuf __P((SM_FILE_T *, int, int));
347 __END_DECLS
348 
349 /*
350 **  The macros are here so that we can
351 **  define function versions in the library.
352 */
353 
354 #define sm_getc(f, t) \
355 	(--(f)->f_r < 0 ? \
356 		sm_rget(f, t) : \
357 		(int)(*(f)->f_p++))
358 
359 /*
360 **  This has been tuned to generate reasonable code on the vax using pcc.
361 **  (It also generates reasonable x86 code using gcc.)
362 */
363 
364 #define sm_putc(f, t, c) \
365 	(--(f)->f_w < 0 ? \
366 		(f)->f_w >= (f)->f_lbfsize ? \
367 			(*(f)->f_p = (c)), *(f)->f_p != '\n' ? \
368 				(int)*(f)->f_p++ : \
369 				sm_wbuf(f, t, '\n') : \
370 			sm_wbuf(f, t, (int)(c)) : \
371 		(*(f)->f_p = (c), (int)*(f)->f_p++))
372 
373 #define sm_eof(p)	(((p)->f_flags & SMFEOF) != 0)
374 #define sm_error(p)	(((p)->f_flags & SMERR) != 0)
375 #define sm_clearerr(p)	((void)((p)->f_flags &= ~(SMERR|SMFEOF)))
376 
377 #define sm_io_eof(p)	sm_eof(p)
378 #define sm_io_error(p)	sm_error(p)
379 
380 #define sm_io_clearerr(p)	sm_clearerr(p)
381 
382 #ifndef lint
383 # ifndef _POSIX_SOURCE
384 #  define sm_io_getc(fp, t)	sm_getc(fp, t)
385 #  define sm_io_putc(fp, t, x)	sm_putc(fp, t, x)
386 # endif /* _POSIX_SOURCE */
387 #endif /* lint */
388 
389 #endif /* SM_IO_H */
390