devd.cc revision 246121 
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: head/sbin/devd/devd.cc 246121 2013-01-30 15:21:18Z ian $");
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
104using namespace std;
105
106extern FILE *yyin;
107extern int lineno;
108
109static const char notify = '!';
110static const char nomatch = '?';
111static const char attach = '+';
112static const char detach = '-';
113
114static struct pidfh *pfh;
115
116int Dflag;
117int dflag;
118int nflag;
119int romeo_must_die = 0;
120
121static const char *configfile = CF;
122
123static void event_loop(void);
124static void usage(void);
125
126template <class T> void
127delete_and_clear(vector<T *> &v)
128{
129	typename vector<T *>::const_iterator i;
130
131	for (i = v.begin(); i != v.end(); ++i)
132		delete *i;
133	v.clear();
134}
135
136config cfg;
137
138event_proc::event_proc() : _prio(-1)
139{
140	// nothing
141}
142
143event_proc::~event_proc()
144{
145	delete_and_clear(_epsvec);
146}
147
148void
149event_proc::add(eps *eps)
150{
151	_epsvec.push_back(eps);
152}
153
154bool
155event_proc::matches(config &c) const
156{
157	vector<eps *>::const_iterator i;
158
159	for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
160		if (!(*i)->do_match(c))
161			return (false);
162	return (true);
163}
164
165bool
166event_proc::run(config &c) const
167{
168	vector<eps *>::const_iterator i;
169
170	for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
171		if (!(*i)->do_action(c))
172			return (false);
173	return (true);
174}
175
176action::action(const char *cmd)
177	: _cmd(cmd)
178{
179	// nothing
180}
181
182action::~action()
183{
184	// nothing
185}
186
187static int
188my_system(const char *command)
189{
190	pid_t pid, savedpid;
191	int pstat;
192	struct sigaction ign, intact, quitact;
193	sigset_t newsigblock, oldsigblock;
194
195	if (!command)		/* just checking... */
196		return(1);
197
198	/*
199	 * Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save
200	 * existing signal dispositions.
201	 */
202	ign.sa_handler = SIG_IGN;
203	::sigemptyset(&ign.sa_mask);
204	ign.sa_flags = 0;
205	::sigaction(SIGINT, &ign, &intact);
206	::sigaction(SIGQUIT, &ign, &quitact);
207	::sigemptyset(&newsigblock);
208	::sigaddset(&newsigblock, SIGCHLD);
209	::sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock);
210	switch (pid = ::fork()) {
211	case -1:			/* error */
212		break;
213	case 0:				/* child */
214		/*
215		 * Restore original signal dispositions and exec the command.
216		 */
217		::sigaction(SIGINT, &intact, NULL);
218		::sigaction(SIGQUIT,  &quitact, NULL);
219		::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
220		/*
221		 * Close the PID file, and all other open descriptors.
222		 * Inherit std{in,out,err} only.
223		 */
224		cfg.close_pidfile();
225		::closefrom(3);
226		::execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
227		::_exit(127);
228	default:			/* parent */
229		savedpid = pid;
230		do {
231			pid = ::wait4(savedpid, &pstat, 0, (struct rusage *)0);
232		} while (pid == -1 && errno == EINTR);
233		break;
234	}
235	::sigaction(SIGINT, &intact, NULL);
236	::sigaction(SIGQUIT,  &quitact, NULL);
237	::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
238	return (pid == -1 ? -1 : pstat);
239}
240
241bool
242action::do_action(config &c)
243{
244	string s = c.expand_string(_cmd);
245	if (Dflag)
246		fprintf(stderr, "Executing '%s'\n", s.c_str());
247	my_system(s.c_str());
248	return (true);
249}
250
251match::match(config &c, const char *var, const char *re)
252	: _var(var), _re("^")
253{
254	if (!c.expand_string(string(re)).empty() &&
255	    c.expand_string(string(re)).at(0) == '!') {
256		_re.append(c.expand_string(string(re)).substr(1));
257		_inv = 1;
258	} else {
259		_re.append(c.expand_string(string(re)));
260		_inv = 0;
261	}
262	_re.append("$");
263	regcomp(&_regex, _re.c_str(), REG_EXTENDED | REG_NOSUB | REG_ICASE);
264}
265
266match::~match()
267{
268	regfree(&_regex);
269}
270
271bool
272match::do_match(config &c)
273{
274	const string &value = c.get_variable(_var);
275	bool retval;
276
277	if (Dflag)
278		fprintf(stderr, "Testing %s=%s against %s, invert=%d\n",
279		    _var.c_str(), value.c_str(), _re.c_str(), _inv);
280
281	retval = (regexec(&_regex, value.c_str(), 0, NULL, 0) == 0);
282	if (_inv == 1)
283		retval = (retval == 0) ? 1 : 0;
284
285	return retval;
286}
287
288#include <sys/sockio.h>
289#include <net/if.h>
290#include <net/if_media.h>
291
292media::media(config &, const char *var, const char *type)
293	: _var(var), _type(-1)
294{
295	static struct ifmedia_description media_types[] = {
296		{ IFM_ETHER,		"Ethernet" },
297		{ IFM_TOKEN,		"Tokenring" },
298		{ IFM_FDDI,		"FDDI" },
299		{ IFM_IEEE80211,	"802.11" },
300		{ IFM_ATM,		"ATM" },
301		{ -1,			"unknown" },
302		{ 0, NULL },
303	};
304	for (int i = 0; media_types[i].ifmt_string != NULL; ++i)
305		if (strcasecmp(type, media_types[i].ifmt_string) == 0) {
306			_type = media_types[i].ifmt_word;
307			break;
308		}
309}
310
311media::~media()
312{
313}
314
315bool
316media::do_match(config &c)
317{
318	string value;
319	struct ifmediareq ifmr;
320	bool retval;
321	int s;
322
323	// Since we can be called from both a device attach/detach
324	// context where device-name is defined and what we want,
325	// as well as from a link status context, where subsystem is
326	// the name of interest, first try device-name and fall back
327	// to subsystem if none exists.
328	value = c.get_variable("device-name");
329	if (value.length() == 0)
330		value = c.get_variable("subsystem");
331	if (Dflag)
332		fprintf(stderr, "Testing media type of %s against 0x%x\n",
333		    value.c_str(), _type);
334
335	retval = false;
336
337	s = socket(PF_INET, SOCK_DGRAM, 0);
338	if (s >= 0) {
339		memset(&ifmr, 0, sizeof(ifmr));
340		strncpy(ifmr.ifm_name, value.c_str(), sizeof(ifmr.ifm_name));
341
342		if (ioctl(s, SIOCGIFMEDIA, (caddr_t)&ifmr) >= 0 &&
343		    ifmr.ifm_status & IFM_AVALID) {
344			if (Dflag)
345				fprintf(stderr, "%s has media type 0x%x\n",
346				    value.c_str(), IFM_TYPE(ifmr.ifm_active));
347			retval = (IFM_TYPE(ifmr.ifm_active) == _type);
348		} else if (_type == -1) {
349			if (Dflag)
350				fprintf(stderr, "%s has unknown media type\n",
351				    value.c_str());
352			retval = true;
353		}
354		close(s);
355	}
356
357	return retval;
358}
359
360const string var_list::bogus = "_$_$_$_$_B_O_G_U_S_$_$_$_$_";
361const string var_list::nothing = "";
362
363const string &
364var_list::get_variable(const string &var) const
365{
366	map<string, string>::const_iterator i;
367
368	i = _vars.find(var);
369	if (i == _vars.end())
370		return (var_list::bogus);
371	return (i->second);
372}
373
374bool
375var_list::is_set(const string &var) const
376{
377	return (_vars.find(var) != _vars.end());
378}
379
380void
381var_list::set_variable(const string &var, const string &val)
382{
383	if (Dflag)
384		fprintf(stderr, "setting %s=%s\n", var.c_str(), val.c_str());
385	_vars[var] = val;
386}
387
388void
389config::reset(void)
390{
391	_dir_list.clear();
392	delete_and_clear(_var_list_table);
393	delete_and_clear(_attach_list);
394	delete_and_clear(_detach_list);
395	delete_and_clear(_nomatch_list);
396	delete_and_clear(_notify_list);
397}
398
399void
400config::parse_one_file(const char *fn)
401{
402	if (Dflag)
403		fprintf(stderr, "Parsing %s\n", fn);
404	yyin = fopen(fn, "r");
405	if (yyin == NULL)
406		err(1, "Cannot open config file %s", fn);
407	lineno = 1;
408	if (yyparse() != 0)
409		errx(1, "Cannot parse %s at line %d", fn, lineno);
410	fclose(yyin);
411}
412
413void
414config::parse_files_in_dir(const char *dirname)
415{
416	DIR *dirp;
417	struct dirent *dp;
418	char path[PATH_MAX];
419
420	if (Dflag)
421		fprintf(stderr, "Parsing files in %s\n", dirname);
422	dirp = opendir(dirname);
423	if (dirp == NULL)
424		return;
425	readdir(dirp);		/* Skip . */
426	readdir(dirp);		/* Skip .. */
427	while ((dp = readdir(dirp)) != NULL) {
428		if (strcmp(dp->d_name + dp->d_namlen - 5, ".conf") == 0) {
429			snprintf(path, sizeof(path), "%s/%s",
430			    dirname, dp->d_name);
431			parse_one_file(path);
432		}
433	}
434	closedir(dirp);
435}
436
437class epv_greater {
438public:
439	int operator()(event_proc *const&l1, event_proc *const&l2) const
440	{
441		return (l1->get_priority() > l2->get_priority());
442	}
443};
444
445void
446config::sort_vector(vector<event_proc *> &v)
447{
448	stable_sort(v.begin(), v.end(), epv_greater());
449}
450
451void
452config::parse(void)
453{
454	vector<string>::const_iterator i;
455
456	parse_one_file(configfile);
457	for (i = _dir_list.begin(); i != _dir_list.end(); ++i)
458		parse_files_in_dir((*i).c_str());
459	sort_vector(_attach_list);
460	sort_vector(_detach_list);
461	sort_vector(_nomatch_list);
462	sort_vector(_notify_list);
463}
464
465void
466config::open_pidfile()
467{
468	pid_t otherpid;
469
470	if (_pidfile == "")
471		return;
472	pfh = pidfile_open(_pidfile.c_str(), 0600, &otherpid);
473	if (pfh == NULL) {
474		if (errno == EEXIST)
475			errx(1, "devd already running, pid: %d", (int)otherpid);
476		warn("cannot open pid file");
477	}
478}
479
480void
481config::write_pidfile()
482{
483
484	pidfile_write(pfh);
485}
486
487void
488config::close_pidfile()
489{
490
491	pidfile_close(pfh);
492}
493
494void
495config::remove_pidfile()
496{
497
498	pidfile_remove(pfh);
499}
500
501void
502config::add_attach(int prio, event_proc *p)
503{
504	p->set_priority(prio);
505	_attach_list.push_back(p);
506}
507
508void
509config::add_detach(int prio, event_proc *p)
510{
511	p->set_priority(prio);
512	_detach_list.push_back(p);
513}
514
515void
516config::add_directory(const char *dir)
517{
518	_dir_list.push_back(string(dir));
519}
520
521void
522config::add_nomatch(int prio, event_proc *p)
523{
524	p->set_priority(prio);
525	_nomatch_list.push_back(p);
526}
527
528void
529config::add_notify(int prio, event_proc *p)
530{
531	p->set_priority(prio);
532	_notify_list.push_back(p);
533}
534
535void
536config::set_pidfile(const char *fn)
537{
538	_pidfile = string(fn);
539}
540
541void
542config::push_var_table()
543{
544	var_list *vl;
545
546	vl = new var_list();
547	_var_list_table.push_back(vl);
548	if (Dflag)
549		fprintf(stderr, "Pushing table\n");
550}
551
552void
553config::pop_var_table()
554{
555	delete _var_list_table.back();
556	_var_list_table.pop_back();
557	if (Dflag)
558		fprintf(stderr, "Popping table\n");
559}
560
561void
562config::set_variable(const char *var, const char *val)
563{
564	_var_list_table.back()->set_variable(var, val);
565}
566
567const string &
568config::get_variable(const string &var)
569{
570	vector<var_list *>::reverse_iterator i;
571
572	for (i = _var_list_table.rbegin(); i != _var_list_table.rend(); ++i) {
573		if ((*i)->is_set(var))
574			return ((*i)->get_variable(var));
575	}
576	return (var_list::nothing);
577}
578
579bool
580config::is_id_char(char ch) const
581{
582	return (ch != '\0' && (isalpha(ch) || isdigit(ch) || ch == '_' ||
583	    ch == '-'));
584}
585
586void
587config::expand_one(const char *&src, string &dst)
588{
589	int count;
590	string buffer;
591
592	src++;
593	// $$ -> $
594	if (*src == '$') {
595		dst.append(src++, 1);
596		return;
597	}
598
599	// $(foo) -> $(foo)
600	// Not sure if I want to support this or not, so for now we just pass
601	// it through.
602	if (*src == '(') {
603		dst.append("$");
604		count = 1;
605		/* If the string ends before ) is matched , return. */
606		while (count > 0 && *src) {
607			if (*src == ')')
608				count--;
609			else if (*src == '(')
610				count++;
611			dst.append(src++, 1);
612		}
613		return;
614	}
615
616	// ${^A-Za-z] -> $\1
617	if (!isalpha(*src)) {
618		dst.append("$");
619		dst.append(src++, 1);
620		return;
621	}
622
623	// $var -> replace with value
624	do {
625		buffer.append(src++, 1);
626	} while (is_id_char(*src));
627	buffer.append("", 1);
628	dst.append(get_variable(buffer.c_str()));
629}
630
631const string
632config::expand_string(const string &s)
633{
634	const char *src;
635	string dst;
636
637	src = s.c_str();
638	while (*src) {
639		if (*src == '$')
640			expand_one(src, dst);
641		else
642			dst.append(src++, 1);
643	}
644	dst.append("", 1);
645
646	return (dst);
647}
648
649bool
650config::chop_var(char *&buffer, char *&lhs, char *&rhs)
651{
652	char *walker;
653
654	if (*buffer == '\0')
655		return (false);
656	walker = lhs = buffer;
657	while (is_id_char(*walker))
658		walker++;
659	if (*walker != '=')
660		return (false);
661	walker++;		// skip =
662	if (*walker == '"') {
663		walker++;	// skip "
664		rhs = walker;
665		while (*walker && *walker != '"')
666			walker++;
667		if (*walker != '"')
668			return (false);
669		rhs[-2] = '\0';
670		*walker++ = '\0';
671	} else {
672		rhs = walker;
673		while (*walker && !isspace(*walker))
674			walker++;
675		if (*walker != '\0')
676			*walker++ = '\0';
677		rhs[-1] = '\0';
678	}
679	while (isspace(*walker))
680		walker++;
681	buffer = walker;
682	return (true);
683}
684
685
686char *
687config::set_vars(char *buffer)
688{
689	char *lhs;
690	char *rhs;
691
692	while (1) {
693		if (!chop_var(buffer, lhs, rhs))
694			break;
695		set_variable(lhs, rhs);
696	}
697	return (buffer);
698}
699
700void
701config::find_and_execute(char type)
702{
703	vector<event_proc *> *l;
704	vector<event_proc *>::const_iterator i;
705	const char *s;
706
707	switch (type) {
708	default:
709		return;
710	case notify:
711		l = &_notify_list;
712		s = "notify";
713		break;
714	case nomatch:
715		l = &_nomatch_list;
716		s = "nomatch";
717		break;
718	case attach:
719		l = &_attach_list;
720		s = "attach";
721		break;
722	case detach:
723		l = &_detach_list;
724		s = "detach";
725		break;
726	}
727	if (Dflag)
728		fprintf(stderr, "Processing %s event\n", s);
729	for (i = l->begin(); i != l->end(); ++i) {
730		if ((*i)->matches(*this)) {
731			(*i)->run(*this);
732			break;
733		}
734	}
735
736}
737
738
739static void
740process_event(char *buffer)
741{
742	char type;
743	char *sp;
744
745	sp = buffer + 1;
746	if (Dflag)
747		fprintf(stderr, "Processing event '%s'\n", buffer);
748	type = *buffer++;
749	cfg.push_var_table();
750	// No match doesn't have a device, and the format is a little
751	// different, so handle it separately.
752	switch (type) {
753	case notify:
754		sp = cfg.set_vars(sp);
755		break;
756	case nomatch:
757		//? at location pnp-info on bus
758		sp = strchr(sp, ' ');
759		if (sp == NULL)
760			return;	/* Can't happen? */
761		*sp++ = '\0';
762		while (isspace(*sp))
763			sp++;
764		if (strncmp(sp, "at ", 3) == 0)
765			sp += 3;
766		sp = cfg.set_vars(sp);
767		while (isspace(*sp))
768			sp++;
769		if (strncmp(sp, "on ", 3) == 0)
770			cfg.set_variable("bus", sp + 3);
771		break;
772	case attach:	/*FALLTHROUGH*/
773	case detach:
774		sp = strchr(sp, ' ');
775		if (sp == NULL)
776			return;	/* Can't happen? */
777		*sp++ = '\0';
778		cfg.set_variable("device-name", buffer);
779		while (isspace(*sp))
780			sp++;
781		if (strncmp(sp, "at ", 3) == 0)
782			sp += 3;
783		sp = cfg.set_vars(sp);
784		while (isspace(*sp))
785			sp++;
786		if (strncmp(sp, "on ", 3) == 0)
787			cfg.set_variable("bus", sp + 3);
788		break;
789	}
790
791	cfg.find_and_execute(type);
792	cfg.pop_var_table();
793}
794
795int
796create_socket(const char *name)
797{
798	int fd, slen;
799	struct sockaddr_un sun;
800
801	if ((fd = socket(PF_LOCAL, SOCK_STREAM, 0)) < 0)
802		err(1, "socket");
803	bzero(&sun, sizeof(sun));
804	sun.sun_family = AF_UNIX;
805	strlcpy(sun.sun_path, name, sizeof(sun.sun_path));
806	slen = SUN_LEN(&sun);
807	unlink(name);
808	if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
809	    	err(1, "fcntl");
810	if (::bind(fd, (struct sockaddr *) & sun, slen) < 0)
811		err(1, "bind");
812	listen(fd, 4);
813	chown(name, 0, 0);	/* XXX - root.wheel */
814	chmod(name, 0666);
815	return (fd);
816}
817
818unsigned int max_clients = 10;	/* Default, can be overriden on cmdline. */
819unsigned int num_clients;
820list<int> clients;
821
822void
823notify_clients(const char *data, int len)
824{
825	list<int>::iterator i;
826
827	/*
828	 * Deliver the data to all clients.  Throw clients overboard at the
829	 * first sign of trouble.  This reaps clients who've died or closed
830	 * their sockets, and also clients who are alive but failing to keep up
831	 * (or who are maliciously not reading, to consume buffer space in
832	 * kernel memory or tie up the limited number of available connections).
833	 */
834	for (i = clients.begin(); i != clients.end(); ) {
835		if (write(*i, data, len) != len) {
836			--num_clients;
837			close(*i);
838			i = clients.erase(i);
839		} else
840			++i;
841	}
842}
843
844void
845check_clients(void)
846{
847	int s;
848	struct pollfd pfd;
849	list<int>::iterator i;
850
851	/*
852	 * Check all existing clients to see if any of them have disappeared.
853	 * Normally we reap clients when we get an error trying to send them an
854	 * event.  This check eliminates the problem of an ever-growing list of
855	 * zombie clients because we're never writing to them on a system
856	 * without frequent device-change activity.
857	 */
858	pfd.events = 0;
859	for (i = clients.begin(); i != clients.end(); ) {
860		pfd.fd = *i;
861		s = poll(&pfd, 1, 0);
862		if ((s < 0 && s != EINTR ) ||
863		    (s > 0 && (pfd.revents & POLLHUP))) {
864			--num_clients;
865			close(*i);
866			i = clients.erase(i);
867		} else
868			++i;
869	}
870}
871
872void
873new_client(int fd)
874{
875	int s;
876
877	/*
878	 * First go reap any zombie clients, then accept the connection, and
879	 * shut down the read side to stop clients from consuming kernel memory
880	 * by sending large buffers full of data we'll never read.
881	 */
882	check_clients();
883	s = accept(fd, NULL, NULL);
884	if (s != -1) {
885		shutdown(s, SHUT_RD);
886		clients.push_back(s);
887		++num_clients;
888	}
889}
890
891static void
892event_loop(void)
893{
894	int rv;
895	int fd;
896	char buffer[DEVCTL_MAXBUF];
897	int once = 0;
898	int server_fd, max_fd;
899	int accepting;
900	timeval tv;
901	fd_set fds;
902
903	fd = open(PATH_DEVCTL, O_RDONLY | O_CLOEXEC);
904	if (fd == -1)
905		err(1, "Can't open devctl device %s", PATH_DEVCTL);
906	server_fd = create_socket(PIPE);
907	accepting = 1;
908	max_fd = max(fd, server_fd) + 1;
909	while (1) {
910		if (romeo_must_die)
911			break;
912		if (!once && !dflag && !nflag) {
913			// Check to see if we have any events pending.
914			tv.tv_sec = 0;
915			tv.tv_usec = 0;
916			FD_ZERO(&fds);
917			FD_SET(fd, &fds);
918			rv = select(fd + 1, &fds, &fds, &fds, &tv);
919			// No events -> we've processed all pending events
920			if (rv == 0) {
921				if (Dflag)
922					fprintf(stderr, "Calling daemon\n");
923				cfg.remove_pidfile();
924				cfg.open_pidfile();
925				daemon(0, 0);
926				cfg.write_pidfile();
927				once++;
928			}
929		}
930		/*
931		 * When we've already got the max number of clients, stop
932		 * accepting new connections (don't put server_fd in the set),
933		 * shrink the accept() queue to reject connections quickly, and
934		 * poll the existing clients more often, so that we notice more
935		 * quickly when any of them disappear to free up client slots.
936		 */
937		FD_ZERO(&fds);
938		FD_SET(fd, &fds);
939		if (num_clients < max_clients) {
940			if (!accepting) {
941				listen(server_fd, max_clients);
942				accepting = 1;
943			}
944			FD_SET(server_fd, &fds);
945			tv.tv_sec = 60;
946			tv.tv_usec = 0;
947		} else {
948			if (accepting) {
949				listen(server_fd, 0);
950				accepting = 0;
951			}
952			tv.tv_sec = 2;
953			tv.tv_usec = 0;
954		}
955		rv = select(max_fd, &fds, NULL, NULL, &tv);
956		if (rv == -1) {
957			if (errno == EINTR)
958				continue;
959			err(1, "select");
960		} else if (rv == 0)
961			check_clients();
962		if (FD_ISSET(fd, &fds)) {
963			rv = read(fd, buffer, sizeof(buffer) - 1);
964			if (rv > 0) {
965				notify_clients(buffer, rv);
966				buffer[rv] = '\0';
967				while (buffer[--rv] == '\n')
968					buffer[rv] = '\0';
969				process_event(buffer);
970			} else if (rv < 0) {
971				if (errno != EINTR)
972					break;
973			} else {
974				/* EOF */
975				break;
976			}
977		}
978		if (FD_ISSET(server_fd, &fds))
979			new_client(server_fd);
980	}
981	close(fd);
982}
983
984/*
985 * functions that the parser uses.
986 */
987void
988add_attach(int prio, event_proc *p)
989{
990	cfg.add_attach(prio, p);
991}
992
993void
994add_detach(int prio, event_proc *p)
995{
996	cfg.add_detach(prio, p);
997}
998
999void
1000add_directory(const char *dir)
1001{
1002	cfg.add_directory(dir);
1003	free(const_cast<char *>(dir));
1004}
1005
1006void
1007add_nomatch(int prio, event_proc *p)
1008{
1009	cfg.add_nomatch(prio, p);
1010}
1011
1012void
1013add_notify(int prio, event_proc *p)
1014{
1015	cfg.add_notify(prio, p);
1016}
1017
1018event_proc *
1019add_to_event_proc(event_proc *ep, eps *eps)
1020{
1021	if (ep == NULL)
1022		ep = new event_proc();
1023	ep->add(eps);
1024	return (ep);
1025}
1026
1027eps *
1028new_action(const char *cmd)
1029{
1030	eps *e = new action(cmd);
1031	free(const_cast<char *>(cmd));
1032	return (e);
1033}
1034
1035eps *
1036new_match(const char *var, const char *re)
1037{
1038	eps *e = new match(cfg, var, re);
1039	free(const_cast<char *>(var));
1040	free(const_cast<char *>(re));
1041	return (e);
1042}
1043
1044eps *
1045new_media(const char *var, const char *re)
1046{
1047	eps *e = new media(cfg, var, re);
1048	free(const_cast<char *>(var));
1049	free(const_cast<char *>(re));
1050	return (e);
1051}
1052
1053void
1054set_pidfile(const char *name)
1055{
1056	cfg.set_pidfile(name);
1057	free(const_cast<char *>(name));
1058}
1059
1060void
1061set_variable(const char *var, const char *val)
1062{
1063	cfg.set_variable(var, val);
1064	free(const_cast<char *>(var));
1065	free(const_cast<char *>(val));
1066}
1067
1068
1069
1070static void
1071gensighand(int)
1072{
1073	romeo_must_die++;
1074	_exit(0);
1075}
1076
1077static void
1078usage()
1079{
1080	fprintf(stderr, "usage: %s [-Ddn] [-l connlimit] [-f file]\n",
1081	    getprogname());
1082	exit(1);
1083}
1084
1085static void
1086check_devd_enabled()
1087{
1088	int val = 0;
1089	size_t len;
1090
1091	len = sizeof(val);
1092	if (sysctlbyname(SYSCTL, &val, &len, NULL, 0) != 0)
1093		errx(1, "devctl sysctl missing from kernel!");
1094	if (val) {
1095		warnx("Setting " SYSCTL " to 0");
1096		val = 0;
1097		sysctlbyname(SYSCTL, NULL, NULL, &val, sizeof(val));
1098	}
1099}
1100
1101/*
1102 * main
1103 */
1104int
1105main(int argc, char **argv)
1106{
1107	int ch;
1108
1109	check_devd_enabled();
1110	while ((ch = getopt(argc, argv, "Ddf:l:n")) != -1) {
1111		switch (ch) {
1112		case 'D':
1113			Dflag++;
1114			break;
1115		case 'd':
1116			dflag++;
1117			break;
1118		case 'f':
1119			configfile = optarg;
1120			break;
1121		case 'l':
1122			max_clients = MAX(1, strtoul(optarg, NULL, 0));
1123			break;
1124		case 'n':
1125			nflag++;
1126			break;
1127		default:
1128			usage();
1129		}
1130	}
1131
1132	cfg.parse();
1133	if (!dflag && nflag) {
1134		cfg.open_pidfile();
1135		daemon(0, 0);
1136		cfg.write_pidfile();
1137	}
1138	signal(SIGPIPE, SIG_IGN);
1139	signal(SIGHUP, gensighand);
1140	signal(SIGINT, gensighand);
1141	signal(SIGTERM, gensighand);
1142	event_loop();
1143	return (0);
1144}
1145