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/* -*- c-file-style: "java"; indent-tabs-mode: nil; tab-width: 4; fill-column: 78 -*-
*
* distcc -- A simple distributed compiler system
*
* Copyright (C) 2002, 2003 by Martin Pool <mbp@samba.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*/
/*
* A servant will not be corrected by words: for
* though he understand he will not answer.
* -- Proverbs 29:19
*/
/**
* @file
* @brief Daemon signal handling.
*
* Signals are handled differently in the daemon parent and its children.
*
* When the parent is killed, the entire process group is shut down, and the
* pid file (if any) is removed.
*
* For both cases any temporary files created by the process are removed.
**/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/socket.h>
#include "exitcode.h"
#include "distcc.h"
#include "trace.h"
#include "util.h"
#include "dopt.h"
#include "exec.h"
#include "daemon.h"
#ifdef HAVE_GSSAPI
#include "auth.h"
#endif
/* This stores the pid of the parent daemon. It's used to make sure
* that we only run the whole-group cleanup from inside the parent.
* Remains 0 before parent initialization is complete and when run
* from inetd. */
volatile pid_t dcc_master_pid = 0;
static RETSIGTYPE dcc_daemon_terminate(int);
/**
* Catch all relevant termination signals. Set up in parent and also
* applies to children.
**/
void dcc_daemon_catch_signals(void)
{
/* SIGALRM is caught to allow for built-in timeouts when running test
* cases. */
signal(SIGTERM, &dcc_daemon_terminate);
signal(SIGINT, &dcc_daemon_terminate);
signal(SIGHUP, &dcc_daemon_terminate);
signal(SIGALRM, &dcc_daemon_terminate);
}
/**
* Ignore hangup signal.
*
* This is only used in detached mode to make sure the daemon does not
* quit when whoever started it closes their terminal. In nondetached
* mode, the signal is logged and causes an exit as normal.
**/
void dcc_ignore_sighup(void)
{
signal(SIGHUP, SIG_IGN);
rs_trace("ignoring SIGHUP");
}
/**
* Just log, remove pidfile, and exit.
*
* Called when a daemon gets a fatal signal.
*
* Some cleanup is done only if we're the master/parent daemon.
**/
static RETSIGTYPE dcc_daemon_terminate(int whichsig)
{
int am_parent;
/* Make sure to remove handler before re-raising signal */
signal(whichsig, SIG_DFL);
am_parent = getpid() == dcc_master_pid;
/* syslog is not safe from a signal handler */
if (am_parent && !rs_trace_syslog) {
#ifdef HAVE_STRSIGNAL
rs_log_info("%s", strsignal(whichsig));
#else
rs_log_info("terminated by signal %d", whichsig);
#endif
}
dcc_cleanup_tempfiles_from_signal_handler();
if (am_parent) {
dcc_remove_pid();
/* kill whole group */
kill(0, whichsig);
}
raise(whichsig);
/* malloc() stuff not safe from a signal handler, but keep this here in case
this memory non-leak is to be fixed in the future. */
/*
#ifdef HAVE_GSSAPI
if (dcc_auth_enabled) {
dcc_gssapi_release_credentials();
if (opt_blacklist_enabled || opt_whitelist_enabled) {
dcc_gssapi_free_list();
}
}
#endif*/
}
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