/*
* Copyright (c) 1994-2008 Carnegie Mellon University. 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. The name "Carnegie Mellon University" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For permission or any legal
* details, please contact
* Carnegie Mellon University
* Center for Technology Transfer and Enterprise Creation
* 4615 Forbes Avenue
* Suite 302
* Pittsburgh, PA 15213
* (412) 268-7393, fax: (412) 268-7395
* innovation@andrew.cmu.edu
*
* 4. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by Computing Services
* at Carnegie Mellon University (http://www.cmu.edu/computing/)."
*
* CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
* THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
* FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
* AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*
* $Id: idle.c,v 1.7 2010/01/06 17:01:32 murch Exp $
*/
#include <config.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <syslog.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <syslog.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <signal.h>
#include <string.h>
#include "idle.h"
#include "idled.h"
#include "global.h"
const char *idle_method_desc = "no";
/* function to report mailbox updates to the client */
static idle_updateproc_t *idle_update = NULL;
/* how often to poll the mailbox */
static time_t idle_period = -1;
static int idle_started = 0;
/* UNIX socket variables */
static int notify_sock = -1;
static struct sockaddr_un idle_remote;
static int idle_remote_len = 0;
/*
* Send a message to idled
*/
static int idle_send_msg(int msg, const char *mboxname)
{
idle_data_t idledata;
/* fill the structure */
idledata.msg = msg;
idledata.pid = getpid();
strncpy(idledata.mboxname, mboxname ? mboxname : ".", sizeof(idledata.mboxname));
/* send */
if (sendto(notify_sock, (void *) &idledata,
IDLEDATA_BASE_SIZE+strlen(idledata.mboxname)+1, /* 1 for NULL */
0, (struct sockaddr *) &idle_remote, idle_remote_len) == -1) {
syslog(LOG_ERR, "error sending to idled: %x", msg);
return 0;
}
return 1;
}
/*
* Notify idled of a mailbox change
*/
void idle_notify(const char *mboxname)
{
/* We should try to determine if we need to send this
* (ie, is an imapd is IDLE on 'mailbox'?).
*/
idle_send_msg(IDLE_NOTIFY, mboxname);
}
/*
* Create connection to idled for sending notifications
*/
int idle_enabled(void)
{
if (idle_period == -1) {
int s;
int fdflags;
struct stat sbuf;
const char *idle_sock;
/* get polling period in case we can't connect to idled
* NOTE: if used, a period of zero disables IDLE
*/
idle_period = config_getint(IMAPOPT_IMAPIDLEPOLL);
if (idle_period < 0) idle_period = 0;
if (!idle_period) return 0;
idle_method_desc = "poll";
if ((s = socket(AF_UNIX, SOCK_DGRAM, 0)) == -1) {
return idle_period;
}
idle_remote.sun_family = AF_UNIX;
idle_sock = config_getstring(IMAPOPT_IDLESOCKET);
if (idle_sock) {
strcpy(idle_remote.sun_path, idle_sock);
}
else {
strcpy(idle_remote.sun_path, config_dir);
strcat(idle_remote.sun_path, FNAME_IDLE_SOCK);
}
idle_remote_len = sizeof(idle_remote.sun_family) +
strlen(idle_remote.sun_path) + 1;
/* check that the socket exists */
if (stat(idle_remote.sun_path, &sbuf) < 0) {
close(s);
return idle_period;
}
/* put us in non-blocking mode */
fdflags = fcntl(s, F_GETFD, 0);
if (fdflags != -1) fdflags = fcntl(s, F_SETFL, O_NONBLOCK | fdflags);
if (fdflags == -1) { close(s); return idle_period; }
notify_sock = s;
if (!idle_send_msg(IDLE_NOOP, NULL)) {
close(s);
notify_sock = -1;
return idle_period;
}
/* set the mailbox update notifier */
mailbox_set_updatenotifier(idle_notify);
idle_method_desc = "idled";
return 1;
}
else if (notify_sock != -1) {
/* if the idle socket is already open, we're enabled */
return 1;
}
else {
return idle_period;
}
}
static void idle_handler(int sig)
{
/* ignore the signals, unless the server has started idling */
if (!idle_started) return;
switch (sig) {
case SIGUSR1:
idle_update(IDLE_MAILBOX);
break;
case SIGUSR2:
idle_update(IDLE_ALERT);
break;
case SIGALRM:
idle_update(IDLE_MAILBOX|IDLE_ALERT);
alarm(idle_period);
break;
}
}
int idle_init(idle_updateproc_t *proc)
{
struct sigaction action;
idle_update = proc;
/* We don't want recursive calls to idle_update() */
sigemptyset(&action.sa_mask);
sigaddset(&action.sa_mask, SIGUSR1);
sigaddset(&action.sa_mask, SIGUSR2);
action.sa_flags = 0;
#ifdef SA_RESTART
action.sa_flags |= SA_RESTART;
#endif
action.sa_handler = idle_handler;
/* Setup the signal handlers */
if ((sigaction(SIGUSR1, &action, NULL) < 0) ||
(sigaction(SIGUSR2, &action, NULL) < 0) ||
(sigaction(SIGALRM, &action, NULL) < 0)) {
syslog(LOG_ERR, "sigaction: %m");
/* Cancel receiving signals */
idle_done(NULL);
return 0;
}
return 1;
}
void idle_start(const char *mboxname)
{
idle_started = 1;
/* Tell idled that we're idling */
if (notify_sock == -1 || !idle_send_msg(IDLE_INIT, mboxname)) {
/* otherwise, we'll poll with SIGALRM */
alarm(idle_period);
}
}
void idle_done(const char *mboxname)
{
/* Tell idled that we're done idling */
if (notify_sock != -1) idle_send_msg(IDLE_DONE, mboxname);
/* Cancel alarm */
alarm(0);
/* Remove the signal handlers */
signal(SIGUSR1, SIG_IGN);
signal(SIGUSR2, SIG_IGN);
signal(SIGALRM, SIG_IGN);
idle_update = NULL;
idle_started = 0;
}