xref: /illumos-gate/usr/src/cmd/sendmail/libsm/local.h (revision bdfc6d18da790deeec2e0eb09c625902defe2498)
1 /*
2  * Copyright (c) 2000-2002, 2004 Sendmail, Inc. and its suppliers.
3  *      All rights reserved.
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  * 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: local.h,v 1.51.2.2 2004/01/09 18:32:44 ca Exp $
15  */
16 
17 #pragma ident	"%Z%%M%	%I%	%E% SMI"
18 
19 /*
20 **  Information local to this implementation of stdio,
21 **  in particular, macros and private variables.
22 */
23 
24 #include <sys/time.h>
25 #if !SM_CONF_MEMCHR
26 # include <memory.h>
27 #endif /* !SM_CONF_MEMCHR */
28 #include <sm/heap.h>
29 
30 int	sm_flush __P((SM_FILE_T *, int *));
31 SM_FILE_T	*smfp __P((void));
32 int	sm_refill __P((SM_FILE_T *, int));
33 void	sm_init __P((void));
34 void	sm_cleanup __P((void));
35 void	sm_makebuf __P((SM_FILE_T *));
36 int	sm_whatbuf __P((SM_FILE_T *, size_t *, int *));
37 int	sm_fwalk __P((int (*)(SM_FILE_T *, int *), int *));
38 int	sm_wsetup __P((SM_FILE_T *));
39 int	sm_flags __P((int));
40 SM_FILE_T	*sm_fp __P((const SM_FILE_T *, const int, SM_FILE_T *));
41 int	sm_vprintf __P((int, char const *, va_list));
42 
43 /* std io functions */
44 ssize_t	sm_stdread __P((SM_FILE_T *, char *, size_t));
45 ssize_t	sm_stdwrite __P((SM_FILE_T *, char const *, size_t));
46 off_t	sm_stdseek __P((SM_FILE_T *, off_t, int));
47 int	sm_stdclose __P((SM_FILE_T *));
48 int	sm_stdopen __P((SM_FILE_T *, const void *, int, const void *));
49 int	sm_stdfdopen __P((SM_FILE_T *, const void *, int, const void *));
50 int	sm_stdsetinfo __P((SM_FILE_T *, int , void *));
51 int	sm_stdgetinfo __P((SM_FILE_T *, int , void *));
52 
53 /* stdio io functions */
54 ssize_t	sm_stdioread __P((SM_FILE_T *, char *, size_t));
55 ssize_t	sm_stdiowrite __P((SM_FILE_T *, char const *, size_t));
56 off_t	sm_stdioseek __P((SM_FILE_T *, off_t, int));
57 int	sm_stdioclose __P((SM_FILE_T *));
58 int	sm_stdioopen __P((SM_FILE_T *, const void *, int, const void *));
59 int	sm_stdiosetinfo __P((SM_FILE_T *, int , void *));
60 int	sm_stdiogetinfo __P((SM_FILE_T *, int , void *));
61 
62 /* string io functions */
63 ssize_t	sm_strread __P((SM_FILE_T *, char *, size_t));
64 ssize_t	sm_strwrite __P((SM_FILE_T *, char const *, size_t));
65 off_t	sm_strseek __P((SM_FILE_T *, off_t, int));
66 int	sm_strclose __P((SM_FILE_T *));
67 int	sm_stropen __P((SM_FILE_T *, const void *, int, const void *));
68 int	sm_strsetinfo __P((SM_FILE_T *, int , void *));
69 int	sm_strgetinfo __P((SM_FILE_T *, int , void *));
70 
71 /* syslog io functions */
72 ssize_t	sm_syslogread __P((SM_FILE_T *, char *, size_t));
73 ssize_t	sm_syslogwrite __P((SM_FILE_T *, char const *, size_t));
74 off_t	sm_syslogseek __P((SM_FILE_T *, off_t, int));
75 int	sm_syslogclose __P((SM_FILE_T *));
76 int	sm_syslogopen __P((SM_FILE_T *, const void *, int, const void *));
77 int	sm_syslogsetinfo __P((SM_FILE_T *, int , void *));
78 int	sm_sysloggetinfo __P((SM_FILE_T *, int , void *));
79 
80 /* should be defined in sys/time.h */
81 #ifndef timersub
82 # define timersub(tvp, uvp, vvp)					\
83 	do								\
84 	{								\
85 		(vvp)->tv_sec = (tvp)->tv_sec - (uvp)->tv_sec;		\
86 		(vvp)->tv_usec = (tvp)->tv_usec - (uvp)->tv_usec;	\
87 		if ((vvp)->tv_usec < 0)					\
88 		{							\
89 			(vvp)->tv_sec--;				\
90 			(vvp)->tv_usec += 1000000;			\
91 		}							\
92 	} while (0)
93 #endif /* !timersub */
94 
95 #ifndef timeradd
96 # define timeradd(tvp, uvp, vvp)					\
97 	do								\
98 	{								\
99 		(vvp)->tv_sec = (tvp)->tv_sec + (uvp)->tv_sec;		\
100 		(vvp)->tv_usec = (tvp)->tv_usec + (uvp)->tv_usec;	\
101 		if ((vvp)->tv_usec >= 1000000)				\
102 		{							\
103 			(vvp)->tv_sec++;				\
104 			(vvp)->tv_usec -= 1000000;			\
105 		}							\
106 	} while (0)
107 #endif /* !timeradd */
108 
109 #ifndef timercmp
110 # define timercmp(tvp, uvp, cmp)					\
111 	(((tvp)->tv_sec == (uvp)->tv_sec) ?				\
112 	    ((tvp)->tv_usec cmp (uvp)->tv_usec) :			\
113 	    ((tvp)->tv_sec cmp (uvp)->tv_sec))
114 #endif /* !timercmp */
115 
116 extern bool Sm_IO_DidInit;
117 
118 /* Return true iff the given SM_FILE_T cannot be written now. */
119 #define cantwrite(fp) \
120 	((((fp)->f_flags & SMWR) == 0 || (fp)->f_bf.smb_base == NULL) && \
121 	 sm_wsetup(fp))
122 
123 /*
124 **  Test whether the given stdio file has an active ungetc buffer;
125 **   release such a buffer, without restoring ordinary unread data.
126 */
127 
128 #define HASUB(fp) ((fp)->f_ub.smb_base != NULL)
129 #define FREEUB(fp)					\
130 {							\
131 	if ((fp)->f_ub.smb_base != (fp)->f_ubuf)	\
132 		sm_free((char *)(fp)->f_ub.smb_base);	\
133 	(fp)->f_ub.smb_base = NULL;			\
134 }
135 
136 extern const char SmFileMagic[];
137 
138 #define SM_ALIGN(p)	(((unsigned long)(p) + SM_ALIGN_BITS) & ~SM_ALIGN_BITS)
139 
140 #define sm_io_flockfile(fp)	((void) 0)
141 #define sm_io_funlockfile(fp)	((void) 0)
142 
143 #ifndef FDSET_CAST
144 # define FDSET_CAST		/* empty cast for fd_set arg to select */
145 #endif
146 
147 /*
148 **  SM_CONVERT_TIME -- convert the API timeout flag for select() usage.
149 **
150 **	This takes a 'fp' (a file type pointer) and obtains the "raw"
151 **	file descriptor (fd) if possible. The 'fd' is needed to possibly
152 **	switch the mode of the file (blocking/non-blocking) to match
153 **	the type of timeout. If timeout is SM_TIME_FOREVER then the
154 **	timeout using select won't be needed and the file is best placed
155 **	in blocking mode. If there is to be a finite timeout then the file
156 **	is best placed in non-blocking mode. Then, if not enough can be
157 **	written, select() can be used to test when something can be written
158 **	yet still timeout if the wait is too long.
159 **	If the mode is already in the correct state we don't change it.
160 **	Iff (yes "iff") the 'fd' is "-1" in value then the mode change
161 **	will not happen. This situation arises when a late-binding-to-disk
162 **	file type is in use. An example of this is the sendmail buffered
163 **	file type (in sendmail/bf.c).
164 **
165 **	Parameters
166 **		fp -- the file pointer the timeout is for
167 **		fd -- to become the file descriptor value from 'fp'
168 **		val -- the timeout value to be converted
169 **		time -- a struct timeval holding the converted value
170 **
171 **	Returns
172 **		nothing, this is flow-through code
173 **
174 **	Side Effects:
175 **		May or may not change the mode of a currently open file.
176 **		The file mode may be changed to O_NONBLOCK or ~O_NONBLOCK
177 **		(meaning block). This is done to best match the type of
178 **		timeout and for (possible) use with select().
179 */
180 
181 # define SM_CONVERT_TIME(fp, fd, val, time) { \
182 	if (((fd) = sm_io_getinfo(fp, SM_IO_WHAT_FD, NULL)) == -1) \
183 	{ \
184 		/* can't get an fd, likely internal 'fake' fp */ \
185 		errno = 0; \
186 	} \
187 	if ((val) == SM_TIME_DEFAULT) \
188 		(val) = (fp)->f_timeout; \
189 	if ((val) == SM_TIME_IMMEDIATE || (val) == SM_TIME_FOREVER) \
190 	{ \
191 		(time)->tv_sec = 0; \
192 		(time)->tv_usec = 0; \
193 	} \
194 	else \
195 	{ \
196 		(time)->tv_sec = (val) / 1000; \
197 		(time)->tv_usec = ((val) - ((time)->tv_sec * 1000)) * 10; \
198 	} \
199 	if ((val) == SM_TIME_FOREVER) \
200 	{ \
201 		if ((fp)->f_timeoutstate == SM_TIME_NONBLOCK && (fd) != -1) \
202 		{ \
203 			int ret; \
204 			ret = fcntl((fd), F_GETFL, 0); \
205 			if (ret == -1 || fcntl((fd), F_SETFL, \
206 					       ret & ~O_NONBLOCK) == -1) \
207 			{ \
208 				/* errno should be set */ \
209 				return SM_IO_EOF; \
210 			} \
211 			(fp)->f_timeoutstate = SM_TIME_BLOCK; \
212 			if ((fp)->f_modefp != NULL) \
213 				(fp)->f_modefp->f_timeoutstate = SM_TIME_BLOCK; \
214 		} \
215 	} \
216 	else { \
217 		if ((fp)->f_timeoutstate == SM_TIME_BLOCK && (fd) != -1) \
218 		{ \
219 			int ret; \
220 			ret = fcntl((fd), F_GETFL, 0); \
221 			if (ret == -1 || fcntl((fd), F_SETFL, \
222 					       ret | O_NONBLOCK) == -1) \
223 			{ \
224 				/* errno should be set */ \
225 				return SM_IO_EOF; \
226 			} \
227 			(fp)->f_timeoutstate = SM_TIME_NONBLOCK; \
228 			if ((fp)->f_modefp != NULL) \
229 				(fp)->f_modefp->f_timeoutstate = SM_TIME_NONBLOCK; \
230 		} \
231 	} \
232 }
233 
234 /*
235 **  SM_IO_WR_TIMEOUT -- setup the timeout for the write
236 **
237 **  This #define uses a select() to wait for the 'fd' to become writable.
238 **  The select() can be active for up to 'to' time. The select may not
239 **  use all of the the 'to' time. Hence, the amount of "wall-clock" time is
240 **  measured to decide how much to subtract from 'to' to update it. On some
241 **  BSD-based/like systems the timeout for a select is updated for the
242 **  amount of time used. On many/most systems this does not happen. Therefore
243 **  the updating of 'to' must be done ourselves; a copy of 'to' is passed
244 **  since a BSD-like system will have updated it and we don't want to
245 **  double the time used!
246 **  Note: if a valid 'fd' doesn't exist yet, don't use this (e.g. the
247 **  sendmail buffered file type in sendmail/bf.c; see fvwrite.c).
248 **
249 **	Parameters
250 **		fd -- a file descriptor for doing select() with
251 **		timeout -- the original user set value.
252 **
253 **	Returns
254 **		nothing, this is flow through code
255 **
256 **	Side Effects:
257 **		adjusts 'timeout' for time used
258 */
259 
260 #define SM_IO_WR_TIMEOUT(fp, fd, to) { \
261 	struct timeval sm_io_to_before, sm_io_to_after, sm_io_to_diff; \
262 	struct timeval sm_io_to; \
263 	int sm_io_to_sel; \
264 	fd_set sm_io_to_mask, sm_io_x_mask; \
265 	errno = 0; \
266 	if ((to) == SM_TIME_DEFAULT) \
267 		(to) = (fp)->f_timeout; \
268 	if ((to) == SM_TIME_IMMEDIATE) \
269 	{ \
270 		errno = EAGAIN; \
271 		return SM_IO_EOF; \
272 	} \
273 	else if ((to) == SM_TIME_FOREVER) \
274 	{ \
275 		errno = EINVAL; \
276 		return SM_IO_EOF; \
277 	} \
278 	else \
279 	{ \
280 		sm_io_to.tv_sec = (to) / 1000; \
281 		sm_io_to.tv_usec = ((to) - (sm_io_to.tv_sec * 1000)) * 10; \
282 	} \
283 	if (FD_SETSIZE > 0 && (fd) >= FD_SETSIZE) \
284 	{ \
285 		errno = EINVAL; \
286 		return SM_IO_EOF; \
287 	} \
288 	FD_ZERO(&sm_io_to_mask); \
289 	FD_SET((fd), &sm_io_to_mask); \
290 	FD_ZERO(&sm_io_x_mask); \
291 	FD_SET((fd), &sm_io_x_mask); \
292 	if (gettimeofday(&sm_io_to_before, NULL) < 0) \
293 		return SM_IO_EOF; \
294 	sm_io_to_sel = select((fd) + 1, NULL, &sm_io_to_mask, &sm_io_x_mask, \
295 			      &sm_io_to); \
296 	if (sm_io_to_sel < 0) \
297 	{ \
298 		/* something went wrong, errno set */ \
299 		return SM_IO_EOF; \
300 	} \
301 	else if (sm_io_to_sel == 0) \
302 	{ \
303 		/* timeout */ \
304 		errno = EAGAIN; \
305 		return SM_IO_EOF; \
306 	} \
307 	/* else loop again */ \
308 	if (gettimeofday(&sm_io_to_after, NULL) < 0) \
309 		return SM_IO_EOF; \
310 	timersub(&sm_io_to_before, &sm_io_to_after, &sm_io_to_diff); \
311 	timersub(&sm_io_to, &sm_io_to_diff, &sm_io_to); \
312 	(to) -= (sm_io_to.tv_sec * 1000); \
313 	(to) -= (sm_io_to.tv_usec / 10); \
314 	if ((to) < 0) \
315 		(to) = 0; \
316 }
317 
318 /*
319 **  If there is no 'fd' just error (we can't timeout). If the timeout
320 **  is SM_TIME_FOREVER then there is no need to do a timeout with
321 **  select since this will be a real error.  If the error is not
322 **  EAGAIN/EWOULDBLOCK (from a nonblocking) then it's a real error.
323 **  Specify the condition here as macro so it can be used in several places.
324 */
325 
326 #define IS_IO_ERROR(fd, ret, to) \
327 	((fd) < 0 ||	\
328 	 ((ret) < 0 && errno != EAGAIN && errno != EWOULDBLOCK) ||	\
329 	 (to) == SM_TIME_FOREVER)
330 
331