xref: /titanic_44/usr/src/lib/libresolv2/common/isc/ev_connects.c (revision 56b2bdd1f04d465cfe4a95b88ae5cba5884154e4)
1 /*
2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
3  * Copyright (c) 1995-1999 by Internet Software Consortium
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 /* ev_connects.c - implement asynch connect/accept for the eventlib
19  * vix 16sep96 [initial]
20  */
21 
22 #if !defined(LINT) && !defined(CODECENTER)
23 static const char rcsid[] = "$Id: ev_connects.c,v 1.8 2006/03/09 23:57:56 marka Exp $";
24 #endif
25 
26 /* Import. */
27 
28 #include "port_before.h"
29 #include "fd_setsize.h"
30 
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <sys/ioctl.h>
34 
35 #include <unistd.h>
36 
37 #include <isc/eventlib.h>
38 #include <isc/assertions.h>
39 #include "eventlib_p.h"
40 
41 #include "port_after.h"
42 
43 /* Macros. */
44 
45 #define GETXXXNAME(f, s, sa, len) ( \
46 	(f((s), (&sa), (&len)) >= 0) ? 0 : \
47 		(errno != EAFNOSUPPORT && errno != EOPNOTSUPP) ? -1 : ( \
48 			memset(&(sa), 0, sizeof (sa)), \
49 			(len) = sizeof (sa), \
50 			(sa).sa_family = AF_UNIX, \
51 			0 \
52 		) \
53 	)
54 
55 /* Forward. */
56 
57 static void	listener(evContext ctx, void *uap, int fd, int evmask);
58 static void	connector(evContext ctx, void *uap, int fd, int evmask);
59 
60 /* Public. */
61 
62 int
63 evListen(evContext opaqueCtx, int fd, int maxconn,
64 	 evConnFunc func, void *uap, evConnID *id)
65 {
66 	evContext_p *ctx = opaqueCtx.opaque;
67 	evConn *new;
68 	int mode;
69 
70 	OKNEW(new);
71 	new->flags = EV_CONN_LISTEN;
72 	OKFREE(mode = fcntl(fd, F_GETFL, NULL), new);	/*%< side effect: validate fd. */
73 	/*
74 	 * Remember the nonblocking status.  We assume that either evSelectFD
75 	 * has not been done to this fd, or that if it has then the caller
76 	 * will evCancelConn before they evDeselectFD.  If our assumptions
77 	 * are not met, then we might restore the old nonblocking status
78 	 * incorrectly.
79 	 */
80 	if ((mode & PORT_NONBLOCK) == 0) {
81 #ifdef USE_FIONBIO_IOCTL
82 		int on = 1;
83 		OKFREE(ioctl(fd, FIONBIO, (char *)&on), new);
84 #else
85 		OKFREE(fcntl(fd, F_SETFL, mode | PORT_NONBLOCK), new);
86 #endif
87 		new->flags |= EV_CONN_BLOCK;
88 	}
89 	OKFREE(listen(fd, maxconn), new);
90 	if (evSelectFD(opaqueCtx, fd, EV_READ, listener, new, &new->file) < 0){
91 		int save = errno;
92 
93 		FREE(new);
94 		errno = save;
95 		return (-1);
96 	}
97 	new->flags |= EV_CONN_SELECTED;
98 	new->func = func;
99 	new->uap = uap;
100 	new->fd = fd;
101 	if (ctx->conns != NULL)
102 		ctx->conns->prev = new;
103 	new->prev = NULL;
104 	new->next = ctx->conns;
105 	ctx->conns = new;
106 	if (id)
107 		id->opaque = new;
108 	return (0);
109 }
110 
111 int
112 evConnect(evContext opaqueCtx, int fd, const void *ra, int ralen,
113 	  evConnFunc func, void *uap, evConnID *id)
114 {
115 	evContext_p *ctx = opaqueCtx.opaque;
116 	evConn *new;
117 
118 	OKNEW(new);
119 	new->flags = 0;
120 	/* Do the select() first to get the socket into nonblocking mode. */
121 	if (evSelectFD(opaqueCtx, fd, EV_MASK_ALL,
122 		       connector, new, &new->file) < 0) {
123 		int save = errno;
124 
125 		FREE(new);
126 		errno = save;
127 		return (-1);
128 	}
129 	new->flags |= EV_CONN_SELECTED;
130 	if (connect(fd, ra, ralen) < 0 &&
131 	    errno != EWOULDBLOCK &&
132 	    errno != EAGAIN &&
133 	    errno != EINPROGRESS) {
134 		int save = errno;
135 
136 		(void) evDeselectFD(opaqueCtx, new->file);
137 		FREE(new);
138 		errno = save;
139 		return (-1);
140 	}
141 	/* No error, or EWOULDBLOCK.  select() tells when it's ready. */
142 	new->func = func;
143 	new->uap = uap;
144 	new->fd = fd;
145 	if (ctx->conns != NULL)
146 		ctx->conns->prev = new;
147 	new->prev = NULL;
148 	new->next = ctx->conns;
149 	ctx->conns = new;
150 	if (id)
151 		id->opaque = new;
152 	return (0);
153 }
154 
155 int
156 evCancelConn(evContext opaqueCtx, evConnID id) {
157 	evContext_p *ctx = opaqueCtx.opaque;
158 	evConn *this = id.opaque;
159 	evAccept *acc, *nxtacc;
160 	int mode;
161 
162 	if ((this->flags & EV_CONN_SELECTED) != 0)
163 		(void) evDeselectFD(opaqueCtx, this->file);
164 	if ((this->flags & EV_CONN_BLOCK) != 0) {
165 		mode = fcntl(this->fd, F_GETFL, NULL);
166 		if (mode == -1) {
167 			if (errno != EBADF)
168 				return (-1);
169 		} else {
170 #ifdef USE_FIONBIO_IOCTL
171 			int off = 0;
172 			OK(ioctl(this->fd, FIONBIO, (char *)&off));
173 #else
174 			OK(fcntl(this->fd, F_SETFL, mode & ~PORT_NONBLOCK));
175 #endif
176 		}
177 	}
178 
179 	/* Unlink from ctx->conns. */
180 	if (this->prev != NULL)
181 		this->prev->next = this->next;
182 	else
183 		ctx->conns = this->next;
184 	if (this->next != NULL)
185 		this->next->prev = this->prev;
186 
187 	/*
188 	 * Remove `this' from the ctx->accepts list (zero or more times).
189 	 */
190 	for (acc = HEAD(ctx->accepts), nxtacc = NULL;
191 	     acc != NULL;
192 	     acc = nxtacc)
193 	{
194 		nxtacc = NEXT(acc, link);
195 		if (acc->conn == this) {
196 			UNLINK(ctx->accepts, acc, link);
197 			close(acc->fd);
198 			FREE(acc);
199 		}
200 	}
201 
202 	/* Wrap up and get out. */
203 	FREE(this);
204 	return (0);
205 }
206 
207 int evHold(evContext opaqueCtx, evConnID id) {
208 	evConn *this = id.opaque;
209 
210 	if ((this->flags & EV_CONN_LISTEN) == 0) {
211 		errno = EINVAL;
212 		return (-1);
213 	}
214 	if ((this->flags & EV_CONN_SELECTED) == 0)
215 		return (0);
216 	this->flags &= ~EV_CONN_SELECTED;
217 	return (evDeselectFD(opaqueCtx, this->file));
218 }
219 
220 int evUnhold(evContext opaqueCtx, evConnID id) {
221 	evConn *this = id.opaque;
222 	int ret;
223 
224 	if ((this->flags & EV_CONN_LISTEN) == 0) {
225 		errno = EINVAL;
226 		return (-1);
227 	}
228 	if ((this->flags & EV_CONN_SELECTED) != 0)
229 		return (0);
230 	ret = evSelectFD(opaqueCtx, this->fd, EV_READ, listener, this,
231 			 &this->file);
232 	if (ret == 0)
233 		this->flags |= EV_CONN_SELECTED;
234 	return (ret);
235 }
236 
237 int
238 evTryAccept(evContext opaqueCtx, evConnID id, int *sys_errno) {
239 	evContext_p *ctx = opaqueCtx.opaque;
240 	evConn *conn = id.opaque;
241 	evAccept *new;
242 
243 	if ((conn->flags & EV_CONN_LISTEN) == 0) {
244 		errno = EINVAL;
245 		return (-1);
246 	}
247 	OKNEW(new);
248 	new->conn = conn;
249 	new->ralen = sizeof new->ra;
250 	new->fd = accept(conn->fd, &new->ra.sa, &new->ralen);
251 	if (new->fd > ctx->highestFD) {
252 		close(new->fd);
253 		new->fd = -1;
254 		new->ioErrno = ENOTSOCK;
255 	}
256 	if (new->fd >= 0) {
257 		new->lalen = sizeof new->la;
258 		if (GETXXXNAME(getsockname, new->fd, new->la.sa, new->lalen) < 0) {
259 			new->ioErrno = errno;
260 			(void) close(new->fd);
261 			new->fd = -1;
262 		} else
263 			new->ioErrno = 0;
264 	} else {
265 		new->ioErrno = errno;
266 		if (errno == EAGAIN || errno == EWOULDBLOCK) {
267 			FREE(new);
268 			return (-1);
269 		}
270 	}
271 	INIT_LINK(new, link);
272 	APPEND(ctx->accepts, new, link);
273 	*sys_errno = new->ioErrno;
274 	return (0);
275 }
276 
277 /* Private. */
278 
279 static void
280 listener(evContext opaqueCtx, void *uap, int fd, int evmask) {
281 	evContext_p *ctx = opaqueCtx.opaque;
282 	evConn *conn = uap;
283 	union {
284 		struct sockaddr    sa;
285 		struct sockaddr_in in;
286 #ifndef NO_SOCKADDR_UN
287 		struct sockaddr_un un;
288 #endif
289 	} la, ra;
290 	int new;
291 	ISC_SOCKLEN_T lalen = 0, ralen;
292 
293 	REQUIRE((evmask & EV_READ) != 0);
294 	ralen = sizeof ra;
295 	new = accept(fd, &ra.sa, &ralen);
296 	if (new > ctx->highestFD) {
297 		close(new);
298 		new = -1;
299 		errno = ENOTSOCK;
300 	}
301 	if (new >= 0) {
302 		lalen = sizeof la;
303 		if (GETXXXNAME(getsockname, new, la.sa, lalen) < 0) {
304 			int save = errno;
305 
306 			(void) close(new);
307 			errno = save;
308 			new = -1;
309 		}
310 	} else if (errno == EAGAIN || errno == EWOULDBLOCK)
311 		return;
312 	(*conn->func)(opaqueCtx, conn->uap, new, &la.sa, lalen, &ra.sa, ralen);
313 }
314 
315 static void
316 connector(evContext opaqueCtx, void *uap, int fd, int evmask) {
317 	evConn *conn = uap;
318 	union {
319 		struct sockaddr    sa;
320 		struct sockaddr_in in;
321 #ifndef NO_SOCKADDR_UN
322 		struct sockaddr_un un;
323 #endif
324 	} la, ra;
325 	ISC_SOCKLEN_T lalen, ralen;
326 #ifndef NETREAD_BROKEN
327 	char buf[1];
328 #endif
329 	void *conn_uap;
330 	evConnFunc conn_func;
331 	evConnID id;
332 	int socket_errno = 0;
333 	ISC_SOCKLEN_T optlen;
334 
335 	UNUSED(evmask);
336 
337 	lalen = sizeof la;
338 	ralen = sizeof ra;
339 	conn_uap = conn->uap;
340 	conn_func = conn->func;
341 	id.opaque = conn;
342 #ifdef SO_ERROR
343 	optlen = sizeof socket_errno;
344 	if (fd < 0 &&
345 	    getsockopt(conn->fd, SOL_SOCKET, SO_ERROR, (char *)&socket_errno,
346 		       &optlen) < 0)
347 		socket_errno = errno;
348 	else
349 		errno = socket_errno;
350 #endif
351 	if (evCancelConn(opaqueCtx, id) < 0 ||
352 	    socket_errno ||
353 #ifdef NETREAD_BROKEN
354 	    0 ||
355 #else
356 	    read(fd, buf, 0) < 0 ||
357 #endif
358 	    GETXXXNAME(getsockname, fd, la.sa, lalen) < 0 ||
359 	    GETXXXNAME(getpeername, fd, ra.sa, ralen) < 0) {
360 		int save = errno;
361 
362 		(void) close(fd);	/*%< XXX closing caller's fd */
363 		errno = save;
364 		fd = -1;
365 	}
366 	(*conn_func)(opaqueCtx, conn_uap, fd, &la.sa, lalen, &ra.sa, ralen);
367 }
368 
369 /*! \file */
370