freebsd-dev/sbin/devd/devd.cc
Alan Somers 91cfa6b8f9 devd(8): Remove pidfile on shutdown
MFC after:	3 weeks
Sponsored by:	Spectra Logic Corp
2017-06-20 19:32:39 +00:00

1306 lines
29 KiB
C++

/*-
* Copyright (c) 2002-2010 M. Warner Losh.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* my_system is a variation on lib/libc/stdlib/system.c:
*
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*
* DEVD control daemon.
*/
// TODO list:
// o devd.conf and devd man pages need a lot of help:
// - devd needs to document the unix domain socket
// - devd.conf needs more details on the supported statements.
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/sysctl.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/un.h>
#include <cctype>
#include <cerrno>
#include <cstdlib>
#include <cstdio>
#include <csignal>
#include <cstring>
#include <cstdarg>
#include <dirent.h>
#include <err.h>
#include <fcntl.h>
#include <libutil.h>
#include <paths.h>
#include <poll.h>
#include <regex.h>
#include <syslog.h>
#include <unistd.h>
#include <algorithm>
#include <map>
#include <string>
#include <list>
#include <stdexcept>
#include <vector>
#include "devd.h" /* C compatible definitions */
#include "devd.hh" /* C++ class definitions */
#define STREAMPIPE "/var/run/devd.pipe"
#define SEQPACKETPIPE "/var/run/devd.seqpacket.pipe"
#define CF "/etc/devd.conf"
#define SYSCTL "hw.bus.devctl_queue"
/*
* Since the client socket is nonblocking, we must increase its send buffer to
* handle brief event storms. On FreeBSD, AF_UNIX sockets don't have a receive
* buffer, so the client can't increase the buffersize by itself.
*
* For example, when creating a ZFS pool, devd emits one 165 character
* resource.fs.zfs.statechange message for each vdev in the pool. The kernel
* allocates a 4608B mbuf for each message. Modern technology places a limit of
* roughly 450 drives/rack, and it's unlikely that a zpool will ever be larger
* than that.
*
* 450 drives * 165 bytes / drive = 74250B of data in the sockbuf
* 450 drives * 4608B / drive = 2073600B of mbufs in the sockbuf
*
* We can't directly set the sockbuf's mbuf limit, but we can do it indirectly.
* The kernel sets it to the minimum of a hard-coded maximum value and sbcc *
* kern.ipc.sockbuf_waste_factor, where sbcc is the socket buffer size set by
* the user. The default value of kern.ipc.sockbuf_waste_factor is 8. If we
* set the bufsize to 256k and use the kern.ipc.sockbuf_waste_factor, then the
* kernel will set the mbuf limit to 2MB, which is just large enough for 450
* drives. It also happens to be the same as the hardcoded maximum value.
*/
#define CLIENT_BUFSIZE 262144
using namespace std;
typedef struct client {
int fd;
int socktype;
} client_t;
extern FILE *yyin;
extern int lineno;
static const char notify = '!';
static const char nomatch = '?';
static const char attach = '+';
static const char detach = '-';
static struct pidfh *pfh;
static int no_daemon = 0;
static int daemonize_quick = 0;
static int quiet_mode = 0;
static unsigned total_events = 0;
static volatile sig_atomic_t got_siginfo = 0;
static volatile sig_atomic_t romeo_must_die = 0;
static const char *configfile = CF;
static void devdlog(int priority, const char* message, ...)
__printflike(2, 3);
static void event_loop(void);
static void usage(void);
template <class T> void
delete_and_clear(vector<T *> &v)
{
typename vector<T *>::const_iterator i;
for (i = v.begin(); i != v.end(); ++i)
delete *i;
v.clear();
}
config cfg;
event_proc::event_proc() : _prio(-1)
{
_epsvec.reserve(4);
}
event_proc::~event_proc()
{
delete_and_clear(_epsvec);
}
void
event_proc::add(eps *eps)
{
_epsvec.push_back(eps);
}
bool
event_proc::matches(config &c) const
{
vector<eps *>::const_iterator i;
for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
if (!(*i)->do_match(c))
return (false);
return (true);
}
bool
event_proc::run(config &c) const
{
vector<eps *>::const_iterator i;
for (i = _epsvec.begin(); i != _epsvec.end(); ++i)
if (!(*i)->do_action(c))
return (false);
return (true);
}
action::action(const char *cmd)
: _cmd(cmd)
{
// nothing
}
action::~action()
{
// nothing
}
static int
my_system(const char *command)
{
pid_t pid, savedpid;
int pstat;
struct sigaction ign, intact, quitact;
sigset_t newsigblock, oldsigblock;
if (!command) /* just checking... */
return (1);
/*
* Ignore SIGINT and SIGQUIT, block SIGCHLD. Remember to save
* existing signal dispositions.
*/
ign.sa_handler = SIG_IGN;
::sigemptyset(&ign.sa_mask);
ign.sa_flags = 0;
::sigaction(SIGINT, &ign, &intact);
::sigaction(SIGQUIT, &ign, &quitact);
::sigemptyset(&newsigblock);
::sigaddset(&newsigblock, SIGCHLD);
::sigprocmask(SIG_BLOCK, &newsigblock, &oldsigblock);
switch (pid = ::fork()) {
case -1: /* error */
break;
case 0: /* child */
/*
* Restore original signal dispositions and exec the command.
*/
::sigaction(SIGINT, &intact, NULL);
::sigaction(SIGQUIT, &quitact, NULL);
::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
/*
* Close the PID file, and all other open descriptors.
* Inherit std{in,out,err} only.
*/
cfg.close_pidfile();
::closefrom(3);
::execl(_PATH_BSHELL, "sh", "-c", command, (char *)NULL);
::_exit(127);
default: /* parent */
savedpid = pid;
do {
pid = ::wait4(savedpid, &pstat, 0, (struct rusage *)0);
} while (pid == -1 && errno == EINTR);
break;
}
::sigaction(SIGINT, &intact, NULL);
::sigaction(SIGQUIT, &quitact, NULL);
::sigprocmask(SIG_SETMASK, &oldsigblock, NULL);
return (pid == -1 ? -1 : pstat);
}
bool
action::do_action(config &c)
{
string s = c.expand_string(_cmd.c_str());
devdlog(LOG_INFO, "Executing '%s'\n", s.c_str());
my_system(s.c_str());
return (true);
}
match::match(config &c, const char *var, const char *re) :
_inv(re[0] == '!'),
_var(var),
_re(c.expand_string(_inv ? re + 1 : re, "^", "$"))
{
regcomp(&_regex, _re.c_str(), REG_EXTENDED | REG_NOSUB | REG_ICASE);
}
match::~match()
{
regfree(&_regex);
}
bool
match::do_match(config &c)
{
const string &value = c.get_variable(_var);
bool retval;
/*
* This function gets called WAY too often to justify calling syslog()
* each time, even at LOG_DEBUG. Because if syslogd isn't running, it
* can consume excessive amounts of systime inside of connect(). Only
* log when we're in -d mode.
*/
if (no_daemon) {
devdlog(LOG_DEBUG, "Testing %s=%s against %s, invert=%d\n",
_var.c_str(), value.c_str(), _re.c_str(), _inv);
}
retval = (regexec(&_regex, value.c_str(), 0, NULL, 0) == 0);
if (_inv == 1)
retval = (retval == 0) ? 1 : 0;
return (retval);
}
#include <sys/sockio.h>
#include <net/if.h>
#include <net/if_media.h>
media::media(config &, const char *var, const char *type)
: _var(var), _type(-1)
{
static struct ifmedia_description media_types[] = {
{ IFM_ETHER, "Ethernet" },
{ IFM_TOKEN, "Tokenring" },
{ IFM_FDDI, "FDDI" },
{ IFM_IEEE80211, "802.11" },
{ IFM_ATM, "ATM" },
{ -1, "unknown" },
{ 0, NULL },
};
for (int i = 0; media_types[i].ifmt_string != NULL; ++i)
if (strcasecmp(type, media_types[i].ifmt_string) == 0) {
_type = media_types[i].ifmt_word;
break;
}
}
media::~media()
{
}
bool
media::do_match(config &c)
{
string value;
struct ifmediareq ifmr;
bool retval;
int s;
// Since we can be called from both a device attach/detach
// context where device-name is defined and what we want,
// as well as from a link status context, where subsystem is
// the name of interest, first try device-name and fall back
// to subsystem if none exists.
value = c.get_variable("device-name");
if (value.empty())
value = c.get_variable("subsystem");
devdlog(LOG_DEBUG, "Testing media type of %s against 0x%x\n",
value.c_str(), _type);
retval = false;
s = socket(PF_INET, SOCK_DGRAM, 0);
if (s >= 0) {
memset(&ifmr, 0, sizeof(ifmr));
strlcpy(ifmr.ifm_name, value.c_str(), sizeof(ifmr.ifm_name));
if (ioctl(s, SIOCGIFMEDIA, (caddr_t)&ifmr) >= 0 &&
ifmr.ifm_status & IFM_AVALID) {
devdlog(LOG_DEBUG, "%s has media type 0x%x\n",
value.c_str(), IFM_TYPE(ifmr.ifm_active));
retval = (IFM_TYPE(ifmr.ifm_active) == _type);
} else if (_type == -1) {
devdlog(LOG_DEBUG, "%s has unknown media type\n",
value.c_str());
retval = true;
}
close(s);
}
return (retval);
}
const string var_list::bogus = "_$_$_$_$_B_O_G_U_S_$_$_$_$_";
const string var_list::nothing = "";
const string &
var_list::get_variable(const string &var) const
{
map<string, string>::const_iterator i;
i = _vars.find(var);
if (i == _vars.end())
return (var_list::bogus);
return (i->second);
}
bool
var_list::is_set(const string &var) const
{
return (_vars.find(var) != _vars.end());
}
/** fix_value
*
* Removes quoted characters that have made it this far. \" are
* converted to ". For all other characters, both \ and following
* character. So the string 'fre\:\"' is translated to 'fred\:"'.
*/
std::string
var_list::fix_value(const std::string &val) const
{
std::string rv(val);
std::string::size_type pos(0);
while ((pos = rv.find("\\\"", pos)) != rv.npos) {
rv.erase(pos, 1);
}
return (rv);
}
void
var_list::set_variable(const string &var, const string &val)
{
/*
* This function gets called WAY too often to justify calling syslog()
* each time, even at LOG_DEBUG. Because if syslogd isn't running, it
* can consume excessive amounts of systime inside of connect(). Only
* log when we're in -d mode.
*/
_vars[var] = fix_value(val);
if (no_daemon)
devdlog(LOG_DEBUG, "setting %s=%s\n", var.c_str(), val.c_str());
}
void
config::reset(void)
{
_dir_list.clear();
delete_and_clear(_var_list_table);
delete_and_clear(_attach_list);
delete_and_clear(_detach_list);
delete_and_clear(_nomatch_list);
delete_and_clear(_notify_list);
}
void
config::parse_one_file(const char *fn)
{
devdlog(LOG_DEBUG, "Parsing %s\n", fn);
yyin = fopen(fn, "r");
if (yyin == NULL)
err(1, "Cannot open config file %s", fn);
lineno = 1;
if (yyparse() != 0)
errx(1, "Cannot parse %s at line %d", fn, lineno);
fclose(yyin);
}
void
config::parse_files_in_dir(const char *dirname)
{
DIR *dirp;
struct dirent *dp;
char path[PATH_MAX];
devdlog(LOG_DEBUG, "Parsing files in %s\n", dirname);
dirp = opendir(dirname);
if (dirp == NULL)
return;
readdir(dirp); /* Skip . */
readdir(dirp); /* Skip .. */
while ((dp = readdir(dirp)) != NULL) {
if (strcmp(dp->d_name + dp->d_namlen - 5, ".conf") == 0) {
snprintf(path, sizeof(path), "%s/%s",
dirname, dp->d_name);
parse_one_file(path);
}
}
closedir(dirp);
}
class epv_greater {
public:
int operator()(event_proc *const&l1, event_proc *const&l2) const
{
return (l1->get_priority() > l2->get_priority());
}
};
void
config::sort_vector(vector<event_proc *> &v)
{
stable_sort(v.begin(), v.end(), epv_greater());
}
void
config::parse(void)
{
vector<string>::const_iterator i;
parse_one_file(configfile);
for (i = _dir_list.begin(); i != _dir_list.end(); ++i)
parse_files_in_dir((*i).c_str());
sort_vector(_attach_list);
sort_vector(_detach_list);
sort_vector(_nomatch_list);
sort_vector(_notify_list);
}
void
config::open_pidfile()
{
pid_t otherpid;
if (_pidfile.empty())
return;
pfh = pidfile_open(_pidfile.c_str(), 0600, &otherpid);
if (pfh == NULL) {
if (errno == EEXIST)
errx(1, "devd already running, pid: %d", (int)otherpid);
warn("cannot open pid file");
}
}
void
config::write_pidfile()
{
pidfile_write(pfh);
}
void
config::close_pidfile()
{
pidfile_close(pfh);
}
void
config::remove_pidfile()
{
pidfile_remove(pfh);
}
void
config::add_attach(int prio, event_proc *p)
{
p->set_priority(prio);
_attach_list.push_back(p);
}
void
config::add_detach(int prio, event_proc *p)
{
p->set_priority(prio);
_detach_list.push_back(p);
}
void
config::add_directory(const char *dir)
{
_dir_list.push_back(string(dir));
}
void
config::add_nomatch(int prio, event_proc *p)
{
p->set_priority(prio);
_nomatch_list.push_back(p);
}
void
config::add_notify(int prio, event_proc *p)
{
p->set_priority(prio);
_notify_list.push_back(p);
}
void
config::set_pidfile(const char *fn)
{
_pidfile = fn;
}
void
config::push_var_table()
{
var_list *vl;
vl = new var_list();
_var_list_table.push_back(vl);
devdlog(LOG_DEBUG, "Pushing table\n");
}
void
config::pop_var_table()
{
delete _var_list_table.back();
_var_list_table.pop_back();
devdlog(LOG_DEBUG, "Popping table\n");
}
void
config::set_variable(const char *var, const char *val)
{
_var_list_table.back()->set_variable(var, val);
}
const string &
config::get_variable(const string &var)
{
vector<var_list *>::reverse_iterator i;
for (i = _var_list_table.rbegin(); i != _var_list_table.rend(); ++i) {
if ((*i)->is_set(var))
return ((*i)->get_variable(var));
}
return (var_list::nothing);
}
bool
config::is_id_char(char ch) const
{
return (ch != '\0' && (isalpha(ch) || isdigit(ch) || ch == '_' ||
ch == '-'));
}
void
config::expand_one(const char *&src, string &dst)
{
int count;
string buffer;
src++;
// $$ -> $
if (*src == '$') {
dst += *src++;
return;
}
// $(foo) -> $(foo)
// Not sure if I want to support this or not, so for now we just pass
// it through.
if (*src == '(') {
dst += '$';
count = 1;
/* If the string ends before ) is matched , return. */
while (count > 0 && *src) {
if (*src == ')')
count--;
else if (*src == '(')
count++;
dst += *src++;
}
return;
}
// $[^-A-Za-z_*] -> $\1
if (!isalpha(*src) && *src != '_' && *src != '-' && *src != '*') {
dst += '$';
dst += *src++;
return;
}
// $var -> replace with value
do {
buffer += *src++;
} while (is_id_char(*src));
dst.append(get_variable(buffer));
}
const string
config::expand_string(const char *src, const char *prepend, const char *append)
{
const char *var_at;
string dst;
/*
* 128 bytes is enough for 2427 of 2438 expansions that happen
* while parsing config files, as tested on 2013-01-30.
*/
dst.reserve(128);
if (prepend != NULL)
dst = prepend;
for (;;) {
var_at = strchr(src, '$');
if (var_at == NULL) {
dst.append(src);
break;
}
dst.append(src, var_at - src);
src = var_at;
expand_one(src, dst);
}
if (append != NULL)
dst.append(append);
return (dst);
}
bool
config::chop_var(char *&buffer, char *&lhs, char *&rhs) const
{
char *walker;
if (*buffer == '\0')
return (false);
walker = lhs = buffer;
while (is_id_char(*walker))
walker++;
if (*walker != '=')
return (false);
walker++; // skip =
if (*walker == '"') {
walker++; // skip "
rhs = walker;
while (*walker && *walker != '"') {
// Skip \" ... We leave it in the string and strip the \ later.
// due to the super simplistic parser that we have here.
if (*walker == '\\' && walker[1] == '"')
walker++;
walker++;
}
if (*walker != '"')
return (false);
rhs[-2] = '\0';
*walker++ = '\0';
} else {
rhs = walker;
while (*walker && !isspace(*walker))
walker++;
if (*walker != '\0')
*walker++ = '\0';
rhs[-1] = '\0';
}
while (isspace(*walker))
walker++;
buffer = walker;
return (true);
}
char *
config::set_vars(char *buffer)
{
char *lhs;
char *rhs;
while (1) {
if (!chop_var(buffer, lhs, rhs))
break;
set_variable(lhs, rhs);
}
return (buffer);
}
void
config::find_and_execute(char type)
{
vector<event_proc *> *l;
vector<event_proc *>::const_iterator i;
const char *s;
switch (type) {
default:
return;
case notify:
l = &_notify_list;
s = "notify";
break;
case nomatch:
l = &_nomatch_list;
s = "nomatch";
break;
case attach:
l = &_attach_list;
s = "attach";
break;
case detach:
l = &_detach_list;
s = "detach";
break;
}
devdlog(LOG_DEBUG, "Processing %s event\n", s);
for (i = l->begin(); i != l->end(); ++i) {
if ((*i)->matches(*this)) {
(*i)->run(*this);
break;
}
}
}
static void
process_event(char *buffer)
{
char type;
char *sp;
struct timeval tv;
char *timestr;
sp = buffer + 1;
devdlog(LOG_INFO, "Processing event '%s'\n", buffer);
type = *buffer++;
cfg.push_var_table();
// $* is the entire line
cfg.set_variable("*", buffer - 1);
// $_ is the entire line without the initial character
cfg.set_variable("_", buffer);
// Save the time this happened (as approximated by when we got
// around to processing it).
gettimeofday(&tv, NULL);
asprintf(&timestr, "%jd.%06ld", (uintmax_t)tv.tv_sec, tv.tv_usec);
cfg.set_variable("timestamp", timestr);
free(timestr);
// Match doesn't have a device, and the format is a little
// different, so handle it separately.
switch (type) {
case notify:
//! (k=v)*
sp = cfg.set_vars(sp);
break;
case nomatch:
//? at location pnp-info on bus
sp = strchr(sp, ' ');
if (sp == NULL)
return; /* Can't happen? */
*sp++ = '\0';
while (isspace(*sp))
sp++;
if (strncmp(sp, "at ", 3) == 0)
sp += 3;
sp = cfg.set_vars(sp);
while (isspace(*sp))
sp++;
if (strncmp(sp, "on ", 3) == 0)
cfg.set_variable("bus", sp + 3);
break;
case attach: /*FALLTHROUGH*/
case detach:
sp = strchr(sp, ' ');
if (sp == NULL)
return; /* Can't happen? */
*sp++ = '\0';
cfg.set_variable("device-name", buffer);
while (isspace(*sp))
sp++;
if (strncmp(sp, "at ", 3) == 0)
sp += 3;
sp = cfg.set_vars(sp);
while (isspace(*sp))
sp++;
if (strncmp(sp, "on ", 3) == 0)
cfg.set_variable("bus", sp + 3);
break;
}
cfg.find_and_execute(type);
cfg.pop_var_table();
}
int
create_socket(const char *name, int socktype)
{
int fd, slen;
struct sockaddr_un sun;
if ((fd = socket(PF_LOCAL, socktype, 0)) < 0)
err(1, "socket");
bzero(&sun, sizeof(sun));
sun.sun_family = AF_UNIX;
strlcpy(sun.sun_path, name, sizeof(sun.sun_path));
slen = SUN_LEN(&sun);
unlink(name);
if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
err(1, "fcntl");
if (::bind(fd, (struct sockaddr *) & sun, slen) < 0)
err(1, "bind");
listen(fd, 4);
if (chown(name, 0, 0)) /* XXX - root.wheel */
err(1, "chown");
if (chmod(name, 0666))
err(1, "chmod");
return (fd);
}
unsigned int max_clients = 10; /* Default, can be overridden on cmdline. */
unsigned int num_clients;
list<client_t> clients;
void
notify_clients(const char *data, int len)
{
list<client_t>::iterator i;
/*
* Deliver the data to all clients. Throw clients overboard at the
* first sign of trouble. This reaps clients who've died or closed
* their sockets, and also clients who are alive but failing to keep up
* (or who are maliciously not reading, to consume buffer space in
* kernel memory or tie up the limited number of available connections).
*/
for (i = clients.begin(); i != clients.end(); ) {
int flags;
if (i->socktype == SOCK_SEQPACKET)
flags = MSG_EOR;
else
flags = 0;
if (send(i->fd, data, len, flags) != len) {
--num_clients;
close(i->fd);
i = clients.erase(i);
devdlog(LOG_WARNING, "notify_clients: send() failed; "
"dropping unresponsive client\n");
} else
++i;
}
}
void
check_clients(void)
{
int s;
struct pollfd pfd;
list<client_t>::iterator i;
/*
* Check all existing clients to see if any of them have disappeared.
* Normally we reap clients when we get an error trying to send them an
* event. This check eliminates the problem of an ever-growing list of
* zombie clients because we're never writing to them on a system
* without frequent device-change activity.
*/
pfd.events = 0;
for (i = clients.begin(); i != clients.end(); ) {
pfd.fd = i->fd;
s = poll(&pfd, 1, 0);
if ((s < 0 && s != EINTR ) ||
(s > 0 && (pfd.revents & POLLHUP))) {
--num_clients;
close(i->fd);
i = clients.erase(i);
devdlog(LOG_NOTICE, "check_clients: "
"dropping disconnected client\n");
} else
++i;
}
}
void
new_client(int fd, int socktype)
{
client_t s;
int sndbuf_size;
/*
* First go reap any zombie clients, then accept the connection, and
* shut down the read side to stop clients from consuming kernel memory
* by sending large buffers full of data we'll never read.
*/
check_clients();
s.socktype = socktype;
s.fd = accept(fd, NULL, NULL);
if (s.fd != -1) {
sndbuf_size = CLIENT_BUFSIZE;
if (setsockopt(s.fd, SOL_SOCKET, SO_SNDBUF, &sndbuf_size,
sizeof(sndbuf_size)))
err(1, "setsockopt");
shutdown(s.fd, SHUT_RD);
clients.push_back(s);
++num_clients;
} else
err(1, "accept");
}
static void
event_loop(void)
{
int rv;
int fd;
char buffer[DEVCTL_MAXBUF];
int once = 0;
int stream_fd, seqpacket_fd, max_fd;
int accepting;
timeval tv;
fd_set fds;
fd = open(PATH_DEVCTL, O_RDONLY | O_CLOEXEC);
if (fd == -1)
err(1, "Can't open devctl device %s", PATH_DEVCTL);
stream_fd = create_socket(STREAMPIPE, SOCK_STREAM);
seqpacket_fd = create_socket(SEQPACKETPIPE, SOCK_SEQPACKET);
accepting = 1;
max_fd = max(fd, max(stream_fd, seqpacket_fd)) + 1;
while (!romeo_must_die) {
if (!once && !no_daemon && !daemonize_quick) {
// Check to see if we have any events pending.
tv.tv_sec = 0;
tv.tv_usec = 0;
FD_ZERO(&fds);
FD_SET(fd, &fds);
rv = select(fd + 1, &fds, &fds, &fds, &tv);
// No events -> we've processed all pending events
if (rv == 0) {
devdlog(LOG_DEBUG, "Calling daemon\n");
cfg.remove_pidfile();
cfg.open_pidfile();
daemon(0, 0);
cfg.write_pidfile();
once++;
}
}
/*
* When we've already got the max number of clients, stop
* accepting new connections (don't put the listening sockets in
* the set), shrink the accept() queue to reject connections
* quickly, and poll the existing clients more often, so that we
* notice more quickly when any of them disappear to free up
* client slots.
*/
FD_ZERO(&fds);
FD_SET(fd, &fds);
if (num_clients < max_clients) {
if (!accepting) {
listen(stream_fd, max_clients);
listen(seqpacket_fd, max_clients);
accepting = 1;
}
FD_SET(stream_fd, &fds);
FD_SET(seqpacket_fd, &fds);
tv.tv_sec = 60;
tv.tv_usec = 0;
} else {
if (accepting) {
listen(stream_fd, 0);
listen(seqpacket_fd, 0);
accepting = 0;
}
tv.tv_sec = 2;
tv.tv_usec = 0;
}
rv = select(max_fd, &fds, NULL, NULL, &tv);
if (got_siginfo) {
devdlog(LOG_NOTICE, "Events received so far=%u\n",
total_events);
got_siginfo = 0;
}
if (rv == -1) {
if (errno == EINTR)
continue;
err(1, "select");
} else if (rv == 0)
check_clients();
if (FD_ISSET(fd, &fds)) {
rv = read(fd, buffer, sizeof(buffer) - 1);
if (rv > 0) {
total_events++;
if (rv == sizeof(buffer) - 1) {
devdlog(LOG_WARNING, "Warning: "
"available event data exceeded "
"buffer space\n");
}
notify_clients(buffer, rv);
buffer[rv] = '\0';
while (buffer[--rv] == '\n')
buffer[rv] = '\0';
try {
process_event(buffer);
}
catch (std::length_error e) {
devdlog(LOG_ERR, "Dropping event %s "
"due to low memory", buffer);
}
} else if (rv < 0) {
if (errno != EINTR)
break;
} else {
/* EOF */
break;
}
}
if (FD_ISSET(stream_fd, &fds))
new_client(stream_fd, SOCK_STREAM);
/*
* Aside from the socket type, both sockets use the same
* protocol, so we can process clients the same way.
*/
if (FD_ISSET(seqpacket_fd, &fds))
new_client(seqpacket_fd, SOCK_SEQPACKET);
}
cfg.remove_pidfile();
close(seqpacket_fd);
close(stream_fd);
close(fd);
}
/*
* functions that the parser uses.
*/
void
add_attach(int prio, event_proc *p)
{
cfg.add_attach(prio, p);
}
void
add_detach(int prio, event_proc *p)
{
cfg.add_detach(prio, p);
}
void
add_directory(const char *dir)
{
cfg.add_directory(dir);
free(const_cast<char *>(dir));
}
void
add_nomatch(int prio, event_proc *p)
{
cfg.add_nomatch(prio, p);
}
void
add_notify(int prio, event_proc *p)
{
cfg.add_notify(prio, p);
}
event_proc *
add_to_event_proc(event_proc *ep, eps *eps)
{
if (ep == NULL)
ep = new event_proc();
ep->add(eps);
return (ep);
}
eps *
new_action(const char *cmd)
{
eps *e = new action(cmd);
free(const_cast<char *>(cmd));
return (e);
}
eps *
new_match(const char *var, const char *re)
{
eps *e = new match(cfg, var, re);
free(const_cast<char *>(var));
free(const_cast<char *>(re));
return (e);
}
eps *
new_media(const char *var, const char *re)
{
eps *e = new media(cfg, var, re);
free(const_cast<char *>(var));
free(const_cast<char *>(re));
return (e);
}
void
set_pidfile(const char *name)
{
cfg.set_pidfile(name);
free(const_cast<char *>(name));
}
void
set_variable(const char *var, const char *val)
{
cfg.set_variable(var, val);
free(const_cast<char *>(var));
free(const_cast<char *>(val));
}
static void
gensighand(int)
{
romeo_must_die = 1;
}
/*
* SIGINFO handler. Will print useful statistics to the syslog or stderr
* as appropriate
*/
static void
siginfohand(int)
{
got_siginfo = 1;
}
/*
* Local logging function. Prints to syslog if we're daemonized; stderr
* otherwise.
*/
static void
devdlog(int priority, const char* fmt, ...)
{
va_list argp;
va_start(argp, fmt);
if (no_daemon)
vfprintf(stderr, fmt, argp);
else if (quiet_mode == 0 || priority <= LOG_WARNING)
vsyslog(priority, fmt, argp);
va_end(argp);
}
static void
usage()
{
fprintf(stderr, "usage: %s [-dnq] [-l connlimit] [-f file]\n",
getprogname());
exit(1);
}
static void
check_devd_enabled()
{
int val = 0;
size_t len;
len = sizeof(val);
if (sysctlbyname(SYSCTL, &val, &len, NULL, 0) != 0)
errx(1, "devctl sysctl missing from kernel!");
if (val == 0) {
warnx("Setting " SYSCTL " to 1000");
val = 1000;
if (sysctlbyname(SYSCTL, NULL, NULL, &val, sizeof(val)))
err(1, "sysctlbyname");
}
}
/*
* main
*/
int
main(int argc, char **argv)
{
int ch;
check_devd_enabled();
while ((ch = getopt(argc, argv, "df:l:nq")) != -1) {
switch (ch) {
case 'd':
no_daemon = 1;
break;
case 'f':
configfile = optarg;
break;
case 'l':
max_clients = MAX(1, strtoul(optarg, NULL, 0));
break;
case 'n':
daemonize_quick = 1;
break;
case 'q':
quiet_mode = 1;
break;
default:
usage();
}
}
cfg.parse();
if (!no_daemon && daemonize_quick) {
cfg.open_pidfile();
daemon(0, 0);
cfg.write_pidfile();
}
signal(SIGPIPE, SIG_IGN);
signal(SIGHUP, gensighand);
signal(SIGINT, gensighand);
signal(SIGTERM, gensighand);
signal(SIGINFO, siginfohand);
event_loop();
return (0);
}