/*
 * Copyright (C) 2000, iAgora LLC.
 * Written by Roger Espel Llima for iAgora LLC, 28-NOV-2000.
 *
 * This program is Free Software.  You can redistribute and/or modify it
 * under the terms specified in the file ``LICENSE'', which is part of
 * the lingerd distribution.  (For the impatient: it's an Apache-style
 * license, without the advertising clause.)
 *
 */

/* 
 * Common definitions betweeen lingerd and the Apache lingerd patches.
 */

/* 
 * Name of the Unix-domain socket that lingerd uses to wait for client
 * connections.  This must be somewhere in the filesystem where lingerd
 * can write; it's better to put it in some non-world-writable
 * directory, but /tmp will do as a default.  If you change it, edit
 * apache-1.3/ap_lingerd.h too.
 */
#define SOCKPATH	"/var/run/lingerd/lingerd.sock"

/* 
 * Definitions specific to lingerd, not used by the Apache patches.
 */
#ifdef IN_LINGERD

/*
 * Name of the file to write the pid of the daemon to.  Set to NULL if
 * you don't want a pidfile at all.
 */
#define PID_FILE	"/var/run/lingerd/lingerd.pid"

/* 
 * What syslog facility to log errors to.  You can set where these
 * errors actually go by editing /etc/syslog.conf.  
 * 
 * If your syslog.conf sends LOG_DAEMON stuff to all of /var/log/syslog,
 * /var/log/daemon.log and /var/log/messages (mine did, go figure why),
 * you might want to change it to log to one place only.
 */
#define LOG_FACILITY	LOG_DAEMON

/*
 * Initial linger time in seconds; this is incremented every time a 
 * read() from the socket succeeds.
 */
#define LINGER_TIME	2	

/*
 * Hard limit to the total linger time on a single socket.
 */
#define LINGER_MAX	30

/*
 * Every once in a while lingerd logs some statistics about its work.
 * This is done once per hour by default.  Set it to a negative number
 * to disable statistics.
 */
#define STAT_PERIOD	3600

/* 
 * Refuse to run if we can only hold fewer than this many sockets open.
 * This is mostly for sanity, and to make sure we don't run a crippled
 * linger daemon.
 */
#define MIN_FD_LIMIT	1024

/* 
 * Hardcoded limit to the number of fd's we'll handle, just in case
 * getrlimit() returns astronomically high results, as it is reported to
 * do on GNU/Hurd.
 */
#define MAX_FD_LIMIT	(16*1024)

/* 
 * Number of socket slots to set aside, out of the array, for things
 * like std{in,out,err} and syslog.
 */
#define SOCK_SETASIDE	8

/* 
 * The time granularity, in milliseconds.  We check the status of all
 * sockets everytime there's activity on a socket, or at least every
 * this many milliseconds.  Don't bother setting this very low because
 * all timeouts are counted in whole seconds anyway.
 */
#define POLL_TIMEOUT	500

/*
 * This is the timeout for poll(), in milliseconds, when there are
 * no lingering sockets at all.  It should be bigger than the
 * regular POLL_TIMEOUT, but much smaller than 1000*STAT_PERIOD.
 */
#define SLOW_TIMEOUT	20000

/*
 * Maximum backlog of pending clients for the listen() call.  Not
 * really very important here, because we get relatively few clients
 * (Apache processes are clients, individual linger sockets aren't).
 */
#define BACKLOG		 20

/*
 * Name of the program, for logging purposes.
 */
#define MY_NAME		"lingerd"

#endif	/* IN_LINGERD */

/*
 * Definitions specific to the Apache patches for lingerd
 */
#ifdef IN_APACHE

/*
 * If the connection to the linger daemon fails, how long to wait before
 * trying again.
 *
 * Note that, if lingerd isn't running when Apache starts, or if you
 * restart lingerd without restarting Apache, each Apache process will
 * connect to lignerd separately, so you will get a connection attempt
 * _per child_ every this many seconds.
 *
 */
#define TRY_CONN_PERIOD		10

/*
 * If Apache can't contact the daemon, should it linger on sockets
 * itself (which is slow), or not (which is unsafe)?  Leave this on (1)
 * while testing lingerd, but turn it off (0) once you come to trust it
 * and depend on the diminished server load.
 */
#define LINGER_ON_FAILURE	1

#endif	/* IN_APACHE */

/*
 * =================================================
 * 	END OF USER-CONFIGURABLE DEFINITIONS
 * =================================================
 */


/* 
 * Some definitions related to fd-passing.
 */

/* 
 * FD passing; supporting Linux glibc 2.x (the BSD4.4 way) and Solaris 2.[78] 
 * (the BSD 4.[23] way) for the moment.
 */

/* 
 * Testing for __sun for lack of anything better; this test borrowed from 
 * the Perl module Socket-PassAccessRights-0.0.3.
 */
#if defined(__sun) && !defined(NEW_FD_PASSING) && !defined(OLD_FD_PASSING) 
#  define OLD_FD_PASSING
#endif


/*
 * With BSD4.4-style fd passing, some macros are sometimes missing;
 * define them if we can.
 */
#ifndef OLD_FD_PASSING

/* 
 * This is arguably broken; most cmsghdr's don't have cmsg_data as a member
 * structure, since it would have to be of length 0.  But most cmsghdr's
 * do have the macro CMSG_DATA already.
 */
#  ifndef CMSG_DATA
#    define CMSG_DATA(cmsg) ((cmsg)->cmsg_data)
#  endif

/* 
 * Length of the SCM_RIGHTS control structure, with one fd
 */
#  ifdef CMSG_SPACE
#    define CONTROLLEN	  (CMSG_SPACE(sizeof(int)))
#  else
#    define CONTROLLEN      (sizeof(struct cmsghdr) + sizeof(int))
#  endif

/*
 * A type big enough to hold a struct cmsghdr with its data.
 */
typedef union {
  struct cmsghdr hdr;
  char buf[CONTROLLEN];
} lingerd_cmsghdr;


#endif	/* OLD_FD_PASSING */