1/*-
2 * Copyright (c) 2002-2010 M. Warner Losh.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * my_system is a variation on lib/libc/stdlib/system.c:
27 *
28 * Copyright (c) 1988, 1993
29 *	The Regents of the University of California.  All rights reserved.
30 *
31 * Redistribution and use in source and binary forms, with or without
32 * modification, are permitted provided that the following conditions
33 * are met:
34 * 1. Redistributions of source code must retain the above copyright
35 *    notice, this list of conditions and the following disclaimer.
36 * 2. Redistributions in binary form must reproduce the above copyright
37 *    notice, this list of conditions and the following disclaimer in the
38 *    documentation and/or other materials provided with the distribution.
39 * 4. Neither the name of the University nor the names of its contributors
40 *    may be used to endorse or promote products derived from this software
41 *    without specific prior written permission.
42 *
43 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
44 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
45 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
47 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53 * SUCH DAMAGE.
54 */
55
56/*
57 * DEVD control daemon.
58 */
59
60// TODO list:
61//	o devd.conf and devd man pages need a lot of help:
62//	  - devd needs to document the unix domain socket
63//	  - devd.conf needs more details on the supported statements.
64
65#include <sys/cdefs.h>
66__FBSDID("$FreeBSD$");
67
68#include <sys/param.h>
69#include <sys/socket.h>
70#include <sys/stat.h>
71#include <sys/sysctl.h>
72#include <sys/types.h>
73#include <sys/wait.h>
74#include <sys/un.h>
75
76#include <ctype.h>
77#include <dirent.h>
78#include <errno.h>
79#include <err.h>
80#include <fcntl.h>
81#include <libutil.h>
82#include <paths.h>
83#include <poll.h>
84#include <regex.h>
85#include <signal.h>
86#include <stdlib.h>
87#include <stdio.h>
88#include <string.h>
89#include <unistd.h>
90
91#include <algorithm>
92#include <map>
93#include <string>
94#include <list>
95#include <vector>
96
97#include "devd.h"		/* C compatible definitions */
98#include "devd.hh"		/* C++ class definitions */
99
100#define PIPE "/var/run/devd.pipe"
101#define CF "/etc/devd.conf"
102#define SYSCTL "hw.bus.devctl_disable"
103
104/*
105 * Since the client socket is nonblocking, we must increase its send buffer to
106 * handle brief event storms.  On FreeBSD, AF_UNIX sockets don't have a receive
107 * buffer, so the client can't increate the buffersize by itself.
108 *
109 * For example, when creating a ZFS pool, devd emits one 165 character
110 * resource.fs.zfs.statechange message for each vdev in the pool.  A 64k
111 * buffer has enough space for almost 400 drives, which would be very large but
112 * not impossibly large pool.  A 128k buffer has enough space for 794 drives,
113 * which is more than can fit in a rack with modern technology.
114 */
115#define CLIENT_BUFSIZE 131072
116
117using namespace std;
118
119extern FILE *yyin;
120extern int lineno;
121
122static const char notify = '!';
123static const char nomatch = '?';
124static const char attach = '+';
125static const char detach = '-';
126
127static struct pidfh *pfh;
128
129int Dflag;
130int dflag;
131int nflag;
132int romeo_must_die = 0;
133
134static const char *configfile = CF;
135
136static void event_loop(void);
137static void usage(void);
138
139template <class T> void
140delete_and_clear(vector<T *> &v)
141{
142	typename vector<T *>::const_iterator i;
143
144	for (i = v.begin(); i != v.end(); ++i)
145		delete *i;
146	v.clear();
147}
148
149config cfg;
150
151event_proc::event_proc() : _prio(-1)
152{
153	_epsvec.reserve(4);
154}
155
156event_proc::~event_proc()
157{
158	delete_and_clear(_epsvec);
159}
160
161void
162event_proc::add(eps *eps)
163{
164	_epsvec.push_back(eps);
165}
166
167bool
168event_proc::matches(config &c) const
169{
170	vector<eps *>::const_iterator i;
171
172	for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
173		if (!(*i)->do_match(c))
174			return (false);
175	return (true);
176}
177
178bool
179event_proc::run(config &c) const
180{
181	vector<eps *>::const_iterator i;
182
183	for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
184		if (!(*i)->do_action(c))
185			return (false);
186	return (true);
187}
188
189action::action(const char *cmd)
190	: _cmd(cmd)
191{
192	// nothing
193}
194
195action::~action()
196{
197	// nothing
198}
199
200static int
201my_system(const char *command)
202{
203	pid_t pid, savedpid;
204	int pstat;
205	struct sigaction ign, intact, quitact;
206	sigset_t newsigblock, oldsigblock;
207
208	if (!command)		/* just checking... */
209		return(1);
210
211	/*
212	 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save
213	 * existing signal dispositions.
214	 */
215	ign.sa_handler = SIG_IGN;
216	::sigemptyset(&ign.sa_mask);
217	ign.sa_flags = 0;
218	::sigaction(SIGINT, &ign, &intact);
219	::sigaction(SIGQUIT, &ign, &quitact);
220	::sigemptyset(&newsigblock);
221	::sigaddset(&newsigblock, SIGCHLD);
222	::sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock);
223	switch (pid = ::fork()) {
224	case -1:			/* error */
225		break;
226	case 0:				/* child */
227		/*
228		 * Restore original signal dispositions and exec the command.
229		 */
230		::sigaction(SIGINT, &intact, NULL);
231		::sigaction(SIGQUIT,  &quitact, NULL);
232		::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
233		/*
234		 * Close the PID file, and all other open descriptors.
235		 * Inherit std{in,out,err} only.
236		 */
237		cfg.close_pidfile();
238		::closefrom(3);
239		::execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
240		::_exit(127);
241	default:			/* parent */
242		savedpid = pid;
243		do {
244			pid = ::wait4(savedpid, &pstat, 0, (struct rusage *)0);
245		} while (pid == -1 && errno == EINTR);
246		break;
247	}
248	::sigaction(SIGINT, &intact, NULL);
249	::sigaction(SIGQUIT,  &quitact, NULL);
250	::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
251	return (pid == -1 ? -1 : pstat);
252}
253
254bool
255action::do_action(config &c)
256{
257	string s = c.expand_string(_cmd.c_str());
258	if (Dflag)
259		fprintf(stderr, "Executing '%s'\n", s.c_str());
260	my_system(s.c_str());
261	return (true);
262}
263
264match::match(config &c, const char *var, const char *re) :
265	_inv(re[0] == '!'),
266	_var(var),
267	_re(c.expand_string(_inv ? re + 1 : re, "^", "$"))
268{
269	regcomp(&_regex, _re.c_str(), REG_EXTENDED | REG_NOSUB | REG_ICASE);
270}
271
272match::~match()
273{
274	regfree(&_regex);
275}
276
277bool
278match::do_match(config &c)
279{
280	const string &value = c.get_variable(_var);
281	bool retval;
282
283	if (Dflag)
284		fprintf(stderr, "Testing %s=%s against %s, invert=%d\n",
285		    _var.c_str(), value.c_str(), _re.c_str(), _inv);
286
287	retval = (regexec(&_regex, value.c_str(), 0, NULL, 0) == 0);
288	if (_inv == 1)
289		retval = (retval == 0) ? 1 : 0;
290
291	return retval;
292}
293
294#include <sys/sockio.h>
295#include <net/if.h>
296#include <net/if_media.h>
297
298media::media(config &, const char *var, const char *type)
299	: _var(var), _type(-1)
300{
301	static struct ifmedia_description media_types[] = {
302		{ IFM_ETHER,		"Ethernet" },
303		{ IFM_TOKEN,		"Tokenring" },
304		{ IFM_FDDI,		"FDDI" },
305		{ IFM_IEEE80211,	"802.11" },
306		{ IFM_ATM,		"ATM" },
307		{ IFM_CARP,		"CARP" },
308		{ -1,			"unknown" },
309		{ 0, NULL },
310	};
311	for (int i = 0; media_types[i].ifmt_string != NULL; ++i)
312		if (strcasecmp(type, media_types[i].ifmt_string) == 0) {
313			_type = media_types[i].ifmt_word;
314			break;
315		}
316}
317
318media::~media()
319{
320}
321
322bool
323media::do_match(config &c)
324{
325	string value;
326	struct ifmediareq ifmr;
327	bool retval;
328	int s;
329
330	// Since we can be called from both a device attach/detach
331	// context where device-name is defined and what we want,
332	// as well as from a link status context, where subsystem is
333	// the name of interest, first try device-name and fall back
334	// to subsystem if none exists.
335	value = c.get_variable("device-name");
336	if (value.length() == 0)
337		value = c.get_variable("subsystem");
338	if (Dflag)
339		fprintf(stderr, "Testing media type of %s against 0x%x\n",
340		    value.c_str(), _type);
341
342	retval = false;
343
344	s = socket(PF_INET, SOCK_DGRAM, 0);
345	if (s >= 0) {
346		memset(&ifmr, 0, sizeof(ifmr));
347		strncpy(ifmr.ifm_name, value.c_str(), sizeof(ifmr.ifm_name));
348
349		if (ioctl(s, SIOCGIFMEDIA, (caddr_t)&ifmr) >= 0 &&
350		    ifmr.ifm_status & IFM_AVALID) {
351			if (Dflag)
352				fprintf(stderr, "%s has media type 0x%x\n",
353				    value.c_str(), IFM_TYPE(ifmr.ifm_active));
354			retval = (IFM_TYPE(ifmr.ifm_active) == _type);
355		} else if (_type == -1) {
356			if (Dflag)
357				fprintf(stderr, "%s has unknown media type\n",
358				    value.c_str());
359			retval = true;
360		}
361		close(s);
362	}
363
364	return retval;
365}
366
367const string var_list::bogus = "_$_$_$_$_B_O_G_U_S_$_$_$_$_";
368const string var_list::nothing = "";
369
370const string &
371var_list::get_variable(const string &var) const
372{
373	map<string, string>::const_iterator i;
374
375	i = _vars.find(var);
376	if (i == _vars.end())
377		return (var_list::bogus);
378	return (i->second);
379}
380
381bool
382var_list::is_set(const string &var) const
383{
384	return (_vars.find(var) != _vars.end());
385}
386
387void
388var_list::set_variable(const string &var, const string &val)
389{
390	if (Dflag)
391		fprintf(stderr, "setting %s=%s\n", var.c_str(), val.c_str());
392	_vars[var] = val;
393}
394
395void
396config::reset(void)
397{
398	_dir_list.clear();
399	delete_and_clear(_var_list_table);
400	delete_and_clear(_attach_list);
401	delete_and_clear(_detach_list);
402	delete_and_clear(_nomatch_list);
403	delete_and_clear(_notify_list);
404}
405
406void
407config::parse_one_file(const char *fn)
408{
409	if (Dflag)
410		fprintf(stderr, "Parsing %s\n", fn);
411	yyin = fopen(fn, "r");
412	if (yyin == NULL)
413		err(1, "Cannot open config file %s", fn);
414	lineno = 1;
415	if (yyparse() != 0)
416		errx(1, "Cannot parse %s at line %d", fn, lineno);
417	fclose(yyin);
418}
419
420void
421config::parse_files_in_dir(const char *dirname)
422{
423	DIR *dirp;
424	struct dirent *dp;
425	char path[PATH_MAX];
426
427	if (Dflag)
428		fprintf(stderr, "Parsing files in %s\n", dirname);
429	dirp = opendir(dirname);
430	if (dirp == NULL)
431		return;
432	readdir(dirp);		/* Skip . */
433	readdir(dirp);		/* Skip .. */
434	while ((dp = readdir(dirp)) != NULL) {
435		if (strcmp(dp->d_name + dp->d_namlen - 5, ".conf") == 0) {
436			snprintf(path, sizeof(path), "%s/%s",
437			    dirname, dp->d_name);
438			parse_one_file(path);
439		}
440	}
441	closedir(dirp);
442}
443
444class epv_greater {
445public:
446	int operator()(event_proc *const&l1, event_proc *const&l2) const
447	{
448		return (l1->get_priority() > l2->get_priority());
449	}
450};
451
452void
453config::sort_vector(vector<event_proc *> &v)
454{
455	stable_sort(v.begin(), v.end(), epv_greater());
456}
457
458void
459config::parse(void)
460{
461	vector<string>::const_iterator i;
462
463	parse_one_file(configfile);
464	for (i = _dir_list.begin(); i != _dir_list.end(); ++i)
465		parse_files_in_dir((*i).c_str());
466	sort_vector(_attach_list);
467	sort_vector(_detach_list);
468	sort_vector(_nomatch_list);
469	sort_vector(_notify_list);
470}
471
472void
473config::open_pidfile()
474{
475	pid_t otherpid;
476
477	if (_pidfile == "")
478		return;
479	pfh = pidfile_open(_pidfile.c_str(), 0600, &otherpid);
480	if (pfh == NULL) {
481		if (errno == EEXIST)
482			errx(1, "devd already running, pid: %d", (int)otherpid);
483		warn("cannot open pid file");
484	}
485}
486
487void
488config::write_pidfile()
489{
490
491	pidfile_write(pfh);
492}
493
494void
495config::close_pidfile()
496{
497
498	pidfile_close(pfh);
499}
500
501void
502config::remove_pidfile()
503{
504
505	pidfile_remove(pfh);
506}
507
508void
509config::add_attach(int prio, event_proc *p)
510{
511	p->set_priority(prio);
512	_attach_list.push_back(p);
513}
514
515void
516config::add_detach(int prio, event_proc *p)
517{
518	p->set_priority(prio);
519	_detach_list.push_back(p);
520}
521
522void
523config::add_directory(const char *dir)
524{
525	_dir_list.push_back(string(dir));
526}
527
528void
529config::add_nomatch(int prio, event_proc *p)
530{
531	p->set_priority(prio);
532	_nomatch_list.push_back(p);
533}
534
535void
536config::add_notify(int prio, event_proc *p)
537{
538	p->set_priority(prio);
539	_notify_list.push_back(p);
540}
541
542void
543config::set_pidfile(const char *fn)
544{
545	_pidfile = string(fn);
546}
547
548void
549config::push_var_table()
550{
551	var_list *vl;
552
553	vl = new var_list();
554	_var_list_table.push_back(vl);
555	if (Dflag)
556		fprintf(stderr, "Pushing table\n");
557}
558
559void
560config::pop_var_table()
561{
562	delete _var_list_table.back();
563	_var_list_table.pop_back();
564	if (Dflag)
565		fprintf(stderr, "Popping table\n");
566}
567
568void
569config::set_variable(const char *var, const char *val)
570{
571	_var_list_table.back()->set_variable(var, val);
572}
573
574const string &
575config::get_variable(const string &var)
576{
577	vector<var_list *>::reverse_iterator i;
578
579	for (i = _var_list_table.rbegin(); i != _var_list_table.rend(); ++i) {
580		if ((*i)->is_set(var))
581			return ((*i)->get_variable(var));
582	}
583	return (var_list::nothing);
584}
585
586bool
587config::is_id_char(char ch) const
588{
589	return (ch != '\0' && (isalpha(ch) || isdigit(ch) || ch == '_' ||
590	    ch == '-'));
591}
592
593void
594config::expand_one(const char *&src, string &dst)
595{
596	int count;
597	string buffer;
598
599	src++;
600	// $$ -> $
601	if (*src == '$') {
602		dst.append(src++, 1);
603		return;
604	}
605
606	// $(foo) -> $(foo)
607	// Not sure if I want to support this or not, so for now we just pass
608	// it through.
609	if (*src == '(') {
610		dst.append("$");
611		count = 1;
612		/* If the string ends before ) is matched , return. */
613		while (count > 0 && *src) {
614			if (*src == ')')
615				count--;
616			else if (*src == '(')
617				count++;
618			dst.append(src++, 1);
619		}
620		return;
621	}
622
623	// ${^A-Za-z] -> $\1
624	if (!isalpha(*src)) {
625		dst.append("$");
626		dst.append(src++, 1);
627		return;
628	}
629
630	// $var -> replace with value
631	do {
632		buffer.append(src++, 1);
633	} while (is_id_char(*src));
634	dst.append(get_variable(buffer.c_str()));
635}
636
637const string
638config::expand_string(const char *src, const char *prepend, const char *append)
639{
640	const char *var_at;
641	string dst;
642
643	/*
644	 * 128 bytes is enough for 2427 of 2438 expansions that happen
645	 * while parsing config files, as tested on 2013-01-30.
646	 */
647	dst.reserve(128);
648
649	if (prepend != NULL)
650		dst = prepend;
651
652	for (;;) {
653		var_at = strchr(src, '$');
654		if (var_at == NULL) {
655			dst.append(src);
656			break;
657		}
658		dst.append(src, var_at - src);
659		src = var_at;
660		expand_one(src, dst);
661	}
662
663	if (append != NULL)
664		dst.append(append);
665
666	return (dst);
667}
668
669bool
670config::chop_var(char *&buffer, char *&lhs, char *&rhs)
671{
672	char *walker;
673
674	if (*buffer == '\0')
675		return (false);
676	walker = lhs = buffer;
677	while (is_id_char(*walker))
678		walker++;
679	if (*walker != '=')
680		return (false);
681	walker++;		// skip =
682	if (*walker == '"') {
683		walker++;	// skip "
684		rhs = walker;
685		while (*walker && *walker != '"')
686			walker++;
687		if (*walker != '"')
688			return (false);
689		rhs[-2] = '\0';
690		*walker++ = '\0';
691	} else {
692		rhs = walker;
693		while (*walker && !isspace(*walker))
694			walker++;
695		if (*walker != '\0')
696			*walker++ = '\0';
697		rhs[-1] = '\0';
698	}
699	while (isspace(*walker))
700		walker++;
701	buffer = walker;
702	return (true);
703}
704
705
706char *
707config::set_vars(char *buffer)
708{
709	char *lhs;
710	char *rhs;
711
712	while (1) {
713		if (!chop_var(buffer, lhs, rhs))
714			break;
715		set_variable(lhs, rhs);
716	}
717	return (buffer);
718}
719
720void
721config::find_and_execute(char type)
722{
723	vector<event_proc *> *l;
724	vector<event_proc *>::const_iterator i;
725	const char *s;
726
727	switch (type) {
728	default:
729		return;
730	case notify:
731		l = &_notify_list;
732		s = "notify";
733		break;
734	case nomatch:
735		l = &_nomatch_list;
736		s = "nomatch";
737		break;
738	case attach:
739		l = &_attach_list;
740		s = "attach";
741		break;
742	case detach:
743		l = &_detach_list;
744		s = "detach";
745		break;
746	}
747	if (Dflag)
748		fprintf(stderr, "Processing %s event\n", s);
749	for (i = l->begin(); i != l->end(); ++i) {
750		if ((*i)->matches(*this)) {
751			(*i)->run(*this);
752			break;
753		}
754	}
755
756}
757
758
759static void
760process_event(char *buffer)
761{
762	char type;
763	char *sp;
764
765	sp = buffer + 1;
766	if (Dflag)
767		fprintf(stderr, "Processing event '%s'\n", buffer);
768	type = *buffer++;
769	cfg.push_var_table();
770	// No match doesn't have a device, and the format is a little
771	// different, so handle it separately.
772	switch (type) {
773	case notify:
774		sp = cfg.set_vars(sp);
775		break;
776	case nomatch:
777		//? at location pnp-info on bus
778		sp = strchr(sp, ' ');
779		if (sp == NULL)
780			return;	/* Can't happen? */
781		*sp++ = '\0';
782		while (isspace(*sp))
783			sp++;
784		if (strncmp(sp, "at ", 3) == 0)
785			sp += 3;
786		sp = cfg.set_vars(sp);
787		while (isspace(*sp))
788			sp++;
789		if (strncmp(sp, "on ", 3) == 0)
790			cfg.set_variable("bus", sp + 3);
791		break;
792	case attach:	/*FALLTHROUGH*/
793	case detach:
794		sp = strchr(sp, ' ');
795		if (sp == NULL)
796			return;	/* Can't happen? */
797		*sp++ = '\0';
798		cfg.set_variable("device-name", buffer);
799		while (isspace(*sp))
800			sp++;
801		if (strncmp(sp, "at ", 3) == 0)
802			sp += 3;
803		sp = cfg.set_vars(sp);
804		while (isspace(*sp))
805			sp++;
806		if (strncmp(sp, "on ", 3) == 0)
807			cfg.set_variable("bus", sp + 3);
808		break;
809	}
810
811	cfg.find_and_execute(type);
812	cfg.pop_var_table();
813}
814
815int
816create_socket(const char *name)
817{
818	int fd, slen;
819	struct sockaddr_un sun;
820
821	if ((fd = socket(PF_LOCAL, SOCK_STREAM, 0)) < 0)
822		err(1, "socket");
823	bzero(&sun, sizeof(sun));
824	sun.sun_family = AF_UNIX;
825	strlcpy(sun.sun_path, name, sizeof(sun.sun_path));
826	slen = SUN_LEN(&sun);
827	unlink(name);
828	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
829	    	err(1, "fcntl");
830	if (::bind(fd, (struct sockaddr *) & sun, slen) < 0)
831		err(1, "bind");
832	listen(fd, 4);
833	chown(name, 0, 0);	/* XXX - root.wheel */
834	chmod(name, 0666);
835	return (fd);
836}
837
838unsigned int max_clients = 10;	/* Default, can be overriden on cmdline. */
839unsigned int num_clients;
840list<int> clients;
841
842void
843notify_clients(const char *data, int len)
844{
845	list<int>::iterator i;
846
847	/*
848	 * Deliver the data to all clients.  Throw clients overboard at the
849	 * first sign of trouble.  This reaps clients who've died or closed
850	 * their sockets, and also clients who are alive but failing to keep up
851	 * (or who are maliciously not reading, to consume buffer space in
852	 * kernel memory or tie up the limited number of available connections).
853	 */
854	for (i = clients.begin(); i != clients.end(); ) {
855		if (write(*i, data, len) != len) {
856			--num_clients;
857			close(*i);
858			i = clients.erase(i);
859		} else
860			++i;
861	}
862}
863
864void
865check_clients(void)
866{
867	int s;
868	struct pollfd pfd;
869	list<int>::iterator i;
870
871	/*
872	 * Check all existing clients to see if any of them have disappeared.
873	 * Normally we reap clients when we get an error trying to send them an
874	 * event.  This check eliminates the problem of an ever-growing list of
875	 * zombie clients because we're never writing to them on a system
876	 * without frequent device-change activity.
877	 */
878	pfd.events = 0;
879	for (i = clients.begin(); i != clients.end(); ) {
880		pfd.fd = *i;
881		s = poll(&pfd, 1, 0);
882		if ((s < 0 && s != EINTR ) ||
883		    (s > 0 && (pfd.revents & POLLHUP))) {
884			--num_clients;
885			close(*i);
886			i = clients.erase(i);
887		} else
888			++i;
889	}
890}
891
892void
893new_client(int fd)
894{
895	int s;
896	int sndbuf_size;
897
898	/*
899	 * First go reap any zombie clients, then accept the connection, and
900	 * shut down the read side to stop clients from consuming kernel memory
901	 * by sending large buffers full of data we'll never read.
902	 */
903	check_clients();
904	s = accept(fd, NULL, NULL);
905	if (s != -1) {
906		sndbuf_size = CLIENT_BUFSIZE;
907		if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &sndbuf_size,
908		    sizeof(sndbuf_size)))
909			err(1, "setsockopt");
910		shutdown(s, SHUT_RD);
911		clients.push_back(s);
912		++num_clients;
913	} else
914		err(1, "accept");
915}
916
917static void
918event_loop(void)
919{
920	int rv;
921	int fd;
922	char buffer[DEVCTL_MAXBUF];
923	int once = 0;
924	int server_fd, max_fd;
925	int accepting;
926	timeval tv;
927	fd_set fds;
928
929	fd = open(PATH_DEVCTL, O_RDONLY);
930	if (fd == -1)
931		err(1, "Can't open devctl device %s", PATH_DEVCTL);
932	if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0)
933		err(1, "Can't set close-on-exec flag on devctl");
934	server_fd = create_socket(PIPE);
935	accepting = 1;
936	max_fd = max(fd, server_fd) + 1;
937	while (1) {
938		if (romeo_must_die)
939			break;
940		if (!once && !dflag && !nflag) {
941			// Check to see if we have any events pending.
942			tv.tv_sec = 0;
943			tv.tv_usec = 0;
944			FD_ZERO(&fds);
945			FD_SET(fd, &fds);
946			rv = select(fd + 1, &fds, &fds, &fds, &tv);
947			// No events -> we've processed all pending events
948			if (rv == 0) {
949				if (Dflag)
950					fprintf(stderr, "Calling daemon\n");
951				cfg.remove_pidfile();
952				cfg.open_pidfile();
953				daemon(0, 0);
954				cfg.write_pidfile();
955				once++;
956			}
957		}
958		/*
959		 * When we've already got the max number of clients, stop
960		 * accepting new connections (don't put server_fd in the set),
961		 * shrink the accept() queue to reject connections quickly, and
962		 * poll the existing clients more often, so that we notice more
963		 * quickly when any of them disappear to free up client slots.
964		 */
965		FD_ZERO(&fds);
966		FD_SET(fd, &fds);
967		if (num_clients < max_clients) {
968			if (!accepting) {
969				listen(server_fd, max_clients);
970				accepting = 1;
971			}
972			FD_SET(server_fd, &fds);
973			tv.tv_sec = 60;
974			tv.tv_usec = 0;
975		} else {
976			if (accepting) {
977				listen(server_fd, 0);
978				accepting = 0;
979			}
980			tv.tv_sec = 2;
981			tv.tv_usec = 0;
982		}
983		rv = select(max_fd, &fds, NULL, NULL, &tv);
984		if (rv == -1) {
985			if (errno == EINTR)
986				continue;
987			err(1, "select");
988		} else if (rv == 0)
989			check_clients();
990		if (FD_ISSET(fd, &fds)) {
991			rv = read(fd, buffer, sizeof(buffer) - 1);
992			if (rv > 0) {
993				notify_clients(buffer, rv);
994				buffer[rv] = '\0';
995				while (buffer[--rv] == '\n')
996					buffer[rv] = '\0';
997				process_event(buffer);
998			} else if (rv < 0) {
999				if (errno != EINTR)
1000					break;
1001			} else {
1002				/* EOF */
1003				break;
1004			}
1005		}
1006		if (FD_ISSET(server_fd, &fds))
1007			new_client(server_fd);
1008	}
1009	close(fd);
1010}
1011
1012/*
1013 * functions that the parser uses.
1014 */
1015void
1016add_attach(int prio, event_proc *p)
1017{
1018	cfg.add_attach(prio, p);
1019}
1020
1021void
1022add_detach(int prio, event_proc *p)
1023{
1024	cfg.add_detach(prio, p);
1025}
1026
1027void
1028add_directory(const char *dir)
1029{
1030	cfg.add_directory(dir);
1031	free(const_cast<char *>(dir));
1032}
1033
1034void
1035add_nomatch(int prio, event_proc *p)
1036{
1037	cfg.add_nomatch(prio, p);
1038}
1039
1040void
1041add_notify(int prio, event_proc *p)
1042{
1043	cfg.add_notify(prio, p);
1044}
1045
1046event_proc *
1047add_to_event_proc(event_proc *ep, eps *eps)
1048{
1049	if (ep == NULL)
1050		ep = new event_proc();
1051	ep->add(eps);
1052	return (ep);
1053}
1054
1055eps *
1056new_action(const char *cmd)
1057{
1058	eps *e = new action(cmd);
1059	free(const_cast<char *>(cmd));
1060	return (e);
1061}
1062
1063eps *
1064new_match(const char *var, const char *re)
1065{
1066	eps *e = new match(cfg, var, re);
1067	free(const_cast<char *>(var));
1068	free(const_cast<char *>(re));
1069	return (e);
1070}
1071
1072eps *
1073new_media(const char *var, const char *re)
1074{
1075	eps *e = new media(cfg, var, re);
1076	free(const_cast<char *>(var));
1077	free(const_cast<char *>(re));
1078	return (e);
1079}
1080
1081void
1082set_pidfile(const char *name)
1083{
1084	cfg.set_pidfile(name);
1085	free(const_cast<char *>(name));
1086}
1087
1088void
1089set_variable(const char *var, const char *val)
1090{
1091	cfg.set_variable(var, val);
1092	free(const_cast<char *>(var));
1093	free(const_cast<char *>(val));
1094}
1095
1096
1097
1098static void
1099gensighand(int)
1100{
1101	romeo_must_die++;
1102	_exit(0);
1103}
1104
1105static void
1106usage()
1107{
1108	fprintf(stderr, "usage: %s [-Ddn] [-l connlimit] [-f file]\n",
1109	    getprogname());
1110	exit(1);
1111}
1112
1113static void
1114check_devd_enabled()
1115{
1116	int val = 0;
1117	size_t len;
1118
1119	len = sizeof(val);
1120	if (sysctlbyname(SYSCTL, &val, &len, NULL, 0) != 0)
1121		errx(1, "devctl sysctl missing from kernel!");
1122	if (val) {
1123		warnx("Setting " SYSCTL " to 0");
1124		val = 0;
1125		sysctlbyname(SYSCTL, NULL, NULL, &val, sizeof(val));
1126	}
1127}
1128
1129/*
1130 * main
1131 */
1132int
1133main(int argc, char **argv)
1134{
1135	int ch;
1136
1137	check_devd_enabled();
1138	while ((ch = getopt(argc, argv, "Ddf:l:n")) != -1) {
1139		switch (ch) {
1140		case 'D':
1141			Dflag++;
1142			break;
1143		case 'd':
1144			dflag++;
1145			break;
1146		case 'f':
1147			configfile = optarg;
1148			break;
1149		case 'l':
1150			max_clients = MAX(1, strtoul(optarg, NULL, 0));
1151			break;
1152		case 'n':
1153			nflag++;
1154			break;
1155		default:
1156			usage();
1157		}
1158	}
1159
1160	cfg.parse();
1161	if (!dflag && nflag) {
1162		cfg.open_pidfile();
1163		daemon(0, 0);
1164		cfg.write_pidfile();
1165	}
1166	signal(SIGPIPE, SIG_IGN);
1167	signal(SIGHUP, gensighand);
1168	signal(SIGINT, gensighand);
1169	signal(SIGTERM, gensighand);
1170	event_loop();
1171	return (0);
1172}
1173