freebsd-skq/sbin/devd/devd.cc
imp ff0432665a Parse the ! lines that will soon be coming from the kernel. These are
a generalized notification mechanism for subsystems wishing to report
events.

Revieded by: njl

# The kernel side seems like it might be causing panics for me, but should
# be forthcoming shortly.
2003-10-24 22:02:29 +00:00

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/*-
* Copyright (c) 2002-2003 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.
*/
/*
* DEVD control daemon.
*/
// TODO list:
// o devd.conf and devd man pages need a lot of help:
// - devd.conf needs to lose the warning about zone files.
// - devd.conf needs more details on the supported statements.
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <err.h>
#include <fcntl.h>
#include <regex.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <algorithm>
#include <map>
#include <string>
#include <vector>
#include "devd.h" /* C compatible definitions */
#include "devd.hh" /* C++ class definitions */
#define CF "/etc/devd.conf"
#define SYSCTL "hw.bus.devctl_disable"
using namespace std;
extern FILE *yyin;
extern int lineno;
static const char notify = '!';
static const char nomatch = '?';
static const char attach = '+';
static const char detach = '-';
int Dflag;
int dflag;
int nflag;
int romeo_must_die = 0;
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)
{
// nothing
}
event_proc::~event_proc()
{
vector<eps *>::const_iterator i;
for (i = _epsvec.begin(); i != _epsvec.end(); i++)
delete *i;
_epsvec.clear();
}
void
event_proc::add(eps *eps)
{
_epsvec.push_back(eps);
}
bool
event_proc::matches(config &c)
{
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)
{
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
}
bool
action::do_action(config &c)
{
string s = c.expand_string(_cmd);
if (Dflag)
fprintf(stderr, "Executing '%s'\n", s.c_str());
::system(s.c_str());
return (true);
}
match::match(config &c, const char *var, const char *re)
: _var(var)
{
string pattern = re;
_re = "^";
_re.append(c.expand_string(string(re)));
_re.append("$");
regcomp(&_regex, _re.c_str(), REG_EXTENDED | REG_NOSUB);
}
match::~match()
{
regfree(&_regex);
}
bool
match::do_match(config &c)
{
string value = c.get_variable(_var);
bool retval;
if (Dflag)
fprintf(stderr, "Testing %s=%s against %s\n", _var.c_str(),
value.c_str(), _re.c_str());
retval = (regexec(&_regex, value.c_str(), 0, NULL, 0) == 0);
return retval;
}
const string var_list::bogus = "_$_$_$_$_B_O_G_U_S_$_$_$_$_";
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());
}
void
var_list::set_variable(const string &var, const string &val)
{
if (Dflag)
fprintf(stderr, "%s=%s\n", var.c_str(), val.c_str());
_vars[var] = val;
}
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)
{
if (Dflag)
printf("Parsing %s\n", fn);
yyin = fopen(fn, "r");
if (yyin == NULL)
err(1, "Cannot open config file %s", fn);
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];
if (Dflag)
printf("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);
}
}
}
class epv_greater {
public:
int operator()(event_proc *const&l1, event_proc *const&l2)
{
return (l1->get_priority() > l2->get_priority());
}
};
void
config::sort_vector(vector<event_proc *> &v)
{
sort(v.begin(), v.end(), epv_greater());
}
void
config::parse(void)
{
vector<string>::const_iterator i;
parse_one_file(CF);
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::drop_pidfile()
{
FILE *fp;
if (_pidfile == "")
return;
fp = fopen(_pidfile.c_str(), "w");
if (fp == NULL)
return;
fprintf(fp, "%d\n", getpid());
fclose(fp);
}
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 = string(fn);
}
void
config::push_var_table()
{
var_list *vl;
vl = new var_list();
_var_list_table.push_back(vl);
if (Dflag)
fprintf(stderr, "Pushing table\n");
}
void
config::pop_var_table()
{
delete _var_list_table.back();
_var_list_table.pop_back();
if (Dflag)
fprintf(stderr, "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)
{
return (ch != '\0' && (isalpha(ch) || isdigit(ch) || ch == '_' ||
ch == '-'));
}
void
config::expand_one(const char *&src, string &dst)
{
int count;
string buffer, varstr;
src++;
// $$ -> $
if (*src == '$') {
dst.append(src++, 1);
return;
}
// $(foo) -> $(foo)
// Not sure if I want to support this or not, so for now we just pass
// it through.
if (*src == '(') {
dst.append("$");
count = 1;
/* If the string ends before ) is matched , return. */
while (count > 0 && *src) {
if (*src == ')')
count--;
else if (*src == '(')
count++;
dst.append(src++, 1);
}
return;
}
// ${^A-Za-z] -> $\1
if (!isalpha(*src)) {
dst.append("$");
dst.append(src++, 1);
return;
}
// $var -> replace with value
do {
buffer.append(src++, 1);
} while (is_id_char(*src));
buffer.append("", 1);
varstr = get_variable(buffer.c_str());
dst.append(varstr);
}
const string
config::expand_string(const string &s)
{
const char *src;
string dst;
src = s.c_str();
while (*src) {
if (*src == '$')
expand_one(src, dst);
else
dst.append(src++, 1);
}
dst.append("", 1);
return (dst);
}
bool
config::chop_var(char *&buffer, char *&lhs, char *&rhs)
{
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 != '"')
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;
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;
}
if (Dflag)
fprintf(stderr, "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;
sp = buffer + 1;
if (Dflag)
fprintf(stderr, "Processing event '%s'\n", buffer);
type = *buffer++;
cfg.push_var_table();
// No match doesn't have a device, and the format is a little
// different, so handle it separately.
switch (type) {
case notify:
sp = cfg.set_vars(sp);
break;
case nomatch:
//?vars at location on bus
sp = cfg.set_vars(sp);
if (strncmp(sp, "at ", 3) == 0)
sp += 3;
sp = cfg.set_vars(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);
if (strncmp(sp, "at ", 3) == 0)
sp += 3;
sp = cfg.set_vars(sp);
if (strncmp(sp, "on ", 3) == 0)
cfg.set_variable("bus", sp + 3);
break;
}
cfg.find_and_execute(type);
cfg.pop_var_table();
}
static void
event_loop(void)
{
int rv;
int fd;
char buffer[DEVCTL_MAXBUF];
int once = 0;
timeval tv;
fd_set fds;
fd = open(PATH_DEVCTL, O_RDONLY);
if (fd == -1)
err(1, "Can't open devctl");
if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0)
err(1, "Can't set close-on-exec flag");
while (1) {
if (romeo_must_die)
break;
if (!once && !dflag && !nflag) {
// 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) {
if (Dflag)
fprintf(stderr, "Calling daemon\n");
daemon(0, 0);
cfg.drop_pidfile();
once++;
}
}
rv = read(fd, buffer, sizeof(buffer) - 1);
if (rv > 0) {
buffer[rv] = '\0';
while (buffer[--rv] == '\n')
buffer[rv] = '\0';
process_event(buffer);
} else if (rv < 0) {
if (errno != EINTR)
break;
} else {
/* EOF */
break;
}
}
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);
}
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++;
_exit(0);
}
static void
usage()
{
fprintf(stderr, "usage: %s [-d]\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) {
warnx("Setting " SYSCTL " to 0");
val = 0;
sysctlbyname(SYSCTL, NULL, NULL, &val, sizeof(val));
}
}
/*
* main
*/
int
main(int argc, char **argv)
{
int ch;
check_devd_enabled();
while ((ch = getopt(argc, argv, "Ddn")) != -1) {
switch (ch) {
case 'D':
Dflag++;
break;
case 'd':
dflag++;
break;
case 'n':
nflag++;
break;
default:
usage();
}
}
cfg.parse();
if (!dflag && nflag) {
daemon(0, 0);
cfg.drop_pidfile();
}
signal(SIGHUP, gensighand);
signal(SIGINT, gensighand);
signal(SIGTERM, gensighand);
event_loop();
return (0);
}