main.c

-

/*
 * $Id: main.c,v 1.290.2.2 1999/05/10 16:30:37 wessels Exp $
 *
 * DEBUG: section 1     Startup and Main Loop
 * AUTHOR: Harvest Derived
 *
 * SQUID Internet Object Cache  http://squid.nlanr.net/Squid/
 * ----------------------------------------------------------
 *
 *  Squid is the result of efforts by numerous individuals from the
 *  Internet community.  Development is led by Duane Wessels of the
 *  National Laboratory for Applied Network Research and funded by the
 *  National Science Foundation.  Squid is Copyrighted (C) 1998 by
 *  Duane Wessels and the University of California San Diego.  Please
 *  see the COPYRIGHT file for full details.  Squid incorporates
 *  software developed and/or copyrighted by other sources.  Please see
 *  the CREDITS file for full details.
 *
 *  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., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 *
 */

#include "squid.h"

/* for error reporting from xmalloc and friends */
extern void (*failure_notify) (const char *);

static int opt_send_signal = -1;
static int opt_no_daemon = 0;
static int opt_parse_cfg_only = 0;
static int httpPortNumOverride = 1;
static int icpPortNumOverride = 1;	/* Want to detect "-u 0" */
static int configured_once = 0;
#if MALLOC_DBG
static int malloc_debug_level = 0;
#endif
static volatile int do_reconfigure = 0;
static volatile int do_rotate = 0;
static volatile int do_shutdown = 0;

static void mainRotate(void);
static void mainReconfigure(void);
static SIGHDLR rotate_logs;
static SIGHDLR reconfigure;
#if ALARM_UPDATES_TIME
static SIGHDLR time_tick;
#endif
static void mainInitialize(void);
static void usage(void);
static void mainParseOptions(int, char **);
static void sendSignal(void);
static void serverConnectionsOpen(void);
static void watch_child(char **);
static void setEffectiveUser(void);
#if MEM_GEN_TRACE
extern void log_trace_done();
extern void log_trace_init(char *);
#endif
static EVH SquidShutdown;
static void mainSetCwd(void);

static void
usage(void)
{
    fprintf(stderr,
	"Usage: %s [-dhsvzCDFNRVYX] [-f config-file] [-[au] port] [-k signal]\n"
	"       -a port   Specify HTTP port number (default: %d).\n"
	"       -d level  Write debugging to stderr also.\n"
	"       -f file   Use given config-file instead of\n"
	"                 %s\n"
	"       -h        Print help message.\n"
	"       -k reconfigure|rotate|shutdown|interrupt|kill|debug|check|parse\n"
	"                 Parse configuration file, then send signal to \n"
	"                 running copy (except -k parse) and exit.\n"
	"       -s        Enable logging to syslog.\n"
	"       -u port   Specify ICP port number (default: %d), disable with 0.\n"
	"       -v        Print version.\n"
	"       -z        Create swap directories\n"
	"       -C        Do not catch fatal signals.\n"
	"       -D        Disable initial DNS tests.\n"
	"       -F        Foreground fast store rebuild.\n"
	"       -N        No daemon mode.\n"
	"       -R        Do not set REUSEADDR on port.\n"
	"       -V        Virtual host httpd-accelerator.\n"
	"       -X        Force full debugging.\n"
	"       -Y        Only return UDP_HIT or UDP_MISS_NOFETCH during fast reload.\n",
	appname, CACHE_HTTP_PORT, DefaultConfigFile, CACHE_ICP_PORT);
    exit(1);
}

static void
mainParseOptions(int argc, char *argv[])
{
    extern char *optarg;
    int c;

    while ((c = getopt(argc, argv, "CDFNRSVYXa:d:f:hk:m::su:vz?")) != -1) {
	switch (c) {
	case 'C':
	    opt_catch_signals = 0;
	    break;
	case 'D':
	    opt_dns_tests = 0;
	    break;
	case 'F':
	    opt_foreground_rebuild = 1;
	    break;
	case 'N':
	    opt_no_daemon = 1;
	    break;
	case 'R':
	    opt_reuseaddr = 0;
	    break;
	case 'S':
	    opt_store_doublecheck = 1;
	    break;
	case 'V':
	    vhost_mode = 1;
	    break;
	case 'X':
	    /* force full debugging */
	    sigusr2_handle(SIGUSR2);
	    break;
	case 'Y':
	    opt_reload_hit_only = 1;
	    break;
	case 'a':
	    httpPortNumOverride = atoi(optarg);
	    break;
	case 'd':
	    opt_debug_stderr = atoi(optarg);
	    break;
	case 'f':
	    xfree(ConfigFile);
	    ConfigFile = xstrdup(optarg);
	    break;
	case 'h':
	    usage();
	    break;
	case 'k':
	    if ((int) strlen(optarg) < 1)
		usage();
	    if (!strncmp(optarg, "reconfigure", strlen(optarg)))
		opt_send_signal = SIGHUP;
	    else if (!strncmp(optarg, "rotate", strlen(optarg)))
#ifdef _SQUID_LINUX_THREADS_
		opt_send_signal = SIGQUIT;
#else
		opt_send_signal = SIGUSR1;
#endif
	    else if (!strncmp(optarg, "debug", strlen(optarg)))
#ifdef _SQUID_LINUX_THREADS_
		opt_send_signal = SIGTRAP;
#else
		opt_send_signal = SIGUSR2;
#endif
	    else if (!strncmp(optarg, "shutdown", strlen(optarg)))
		opt_send_signal = SIGTERM;
	    else if (!strncmp(optarg, "interrupt", strlen(optarg)))
		opt_send_signal = SIGINT;
	    else if (!strncmp(optarg, "kill", strlen(optarg)))
		opt_send_signal = SIGKILL;
	    else if (!strncmp(optarg, "check", strlen(optarg)))
		opt_send_signal = 0;	/* SIGNULL */
	    else if (!strncmp(optarg, "parse", strlen(optarg)))
		opt_parse_cfg_only = 1;		/* parse cfg file only */
	    else
		usage();
	    break;
	case 'm':
	    if (optarg) {
#if MALLOC_DBG
		malloc_debug_level = atoi(optarg);
		/* NOTREACHED */
		break;
#else
		fatal("Need to add -DMALLOC_DBG when compiling to use -mX option");
		/* NOTREACHED */
#endif
	    } else {
#if XMALLOC_TRACE
		xmalloc_trace = !xmalloc_trace;
#else
		fatal("Need to configure --enable-xmalloc-debug-trace to use -m option");
#endif
	    }
	case 's':
	    opt_syslog_enable = 1;
	    break;
	case 'u':
	    icpPortNumOverride = atoi(optarg);
	    if (icpPortNumOverride < 0)
		icpPortNumOverride = 0;
	    break;
	case 'v':
	    printf("Squid Cache: Version %s\n", version_string);
	    exit(0);
	    /* NOTREACHED */
	case 'z':
	    opt_create_swap_dirs = 1;
	    break;
	case '?':
	default:
	    usage();
	    break;
	}
    }
}

/* ARGSUSED */
static void
rotate_logs(int sig)
{
    do_rotate = 1;
#if !HAVE_SIGACTION
    signal(sig, rotate_logs);
#endif
}

#if ALARM_UPDATES_TIME
static void
time_tick(int sig)
{
    getCurrentTime();
    alarm(1);
#if !HAVE_SIGACTION
    signal(sig, time_tick);
#endif
}

#endif

/* ARGSUSED */
static void
reconfigure(int sig)
{
    do_reconfigure = 1;
#if !HAVE_SIGACTION
    signal(sig, reconfigure);
#endif
}

void
shut_down(int sig)
{
    do_shutdown = sig == SIGINT ? -1 : 1;
#ifdef KILL_PARENT_OPT
    if (getppid() > 1) {
	debug(1, 1) ("Killing RunCache, pid %d\n", getppid());
	kill(getppid(), sig);
    }
#endif
#if SA_RESETHAND == 0
    signal(SIGTERM, SIG_DFL);
    signal(SIGINT, SIG_DFL);
#endif
}

static void
serverConnectionsOpen(void)
{
    clientHttpConnectionsOpen();
    icpConnectionsOpen();
#if USE_HTCP
    htcpInit();
#endif
#ifdef SQUID_SNMP
    snmpConnectionOpen();
#endif
    clientdbInit();
    icmpOpen();
    netdbInit();
    asnInit();
    peerSelectInit();
#if USE_CARP
    carpInit();
#endif
}

void
serverConnectionsClose(void)
{
    assert(shutting_down || reconfiguring);
    clientHttpConnectionsClose();
    icpConnectionShutdown();
#if USE_HTCP
    htcpSocketShutdown();
#endif
    icmpClose();
#ifdef SQUID_SNMP
    snmpConnectionShutdown();
#endif
    asnFreeMemory();
}

static void
mainReconfigure(void)
{
    debug(1, 1) ("Restarting Squid Cache (version %s)...\n", version_string);
    reconfiguring = 1;
    /* Already called serverConnectionsClose and ipcacheShutdownServers() */
    serverConnectionsClose();
    icpConnectionClose();
#if USE_HTCP
    htcpSocketClose();
#endif
#ifdef SQUID_SNMP
    snmpConnectionClose();
#endif
    dnsShutdown();
    redirectShutdown();
    authenticateShutdown();
    storeDirCloseSwapLogs();
    errorClean();
    parseConfigFile(ConfigFile);
    _db_init(Config.Log.log, Config.debugOptions);
    ipcache_restart();		/* clear stuck entries */
    fqdncache_restart();	/* sigh, fqdncache too */
    errorInitialize();		/* reload error pages */
    dnsInit();
    redirectInit();
    authenticateInit();
    serverConnectionsOpen();
    if (theOutIcpConnection >= 0) {
	if (!Config2.Accel.on || Config.onoff.accel_with_proxy)
	    neighbors_open(theOutIcpConnection);
	else
	    debug(1, 1) ("ICP port disabled in httpd_accelerator mode\n");
    }
    storeDirOpenSwapLogs();
    writePidFile();		/* write PID file */
    debug(1, 1) ("Ready to serve requests.\n");
    reconfiguring = 0;
}

static void
mainRotate(void)
{
    icmpClose();
    _db_rotate_log();		/* cache.log */
    storeDirWriteCleanLogs(1);
    storeLogRotate();		/* store.log */
    accessLogRotate();		/* access.log */
    useragentRotateLog();	/* useragent.log */
    icmpOpen();
}

static void
setEffectiveUser(void)
{
    leave_suid();		/* Run as non privilegied user */
#ifdef _SQUID_OS2_
    return;
#endif
    if (geteuid() == 0) {
	debug(0, 0) ("Squid is not safe to run as root!  If you must\n");
	debug(0, 0) ("start Squid as root, then you must configure\n");
	debug(0, 0) ("it to run as a non-priveledged user with the\n");
	debug(0, 0) ("'cache_effective_user' option in the config file.\n");
	fatal("Don't run Squid as root, set 'cache_effective_user'!");
    }
}

static void
mainSetCwd(void)
{
    if (Config.coredump_dir) {
	if (!chdir(Config.coredump_dir)) {
	    debug(0, 1) ("Set Current Directory to %s\n", Config.coredump_dir);
	    return;
	} else {
	    debug(50, 0) ("chdir: %s: %s\n", Config.coredump_dir, xstrerror());
	}
    }
    if (!Config.effectiveUser) {
	char *p = getcwd(NULL, 0);
	debug(0, 1) ("Current Directory is %s\n", p);
	xfree(p);
	return;
    }
    /* we were probably started as root, so cd to a swap
     * directory in case we dump core */
    if (!chdir(storeSwapDir(0))) {
	debug(0, 1) ("Set Current Directory to %s\n", storeSwapDir(0));
	return;
    } else {
	debug(50, 0) ("%s: %s\n", storeSwapDir(0), xstrerror());
	fatal_dump("Cannot cd to swap directory?");
    }
}

static void
mainInitialize(void)
{
    if (opt_catch_signals) {
	squid_signal(SIGSEGV, death, SA_NODEFER | SA_RESETHAND);
	squid_signal(SIGBUS, death, SA_NODEFER | SA_RESETHAND);
    }
    squid_signal(SIGPIPE, SIG_IGN, SA_RESTART);
    squid_signal(SIGCHLD, sig_child, SA_NODEFER | SA_RESTART);