#### iopts: [tls::import] option
    ### How many arguments the following the option to consume
    variable socketOptionRules {
        {0 -async sopts 0}
        {* -myaddr sopts 1}
        {0 -myport sopts 1}
        {* -type sopts 1}
        {* -alpn iopts 1}
        {* -cadir iopts 1}
        {* -cafile iopts 1}
        {* -cert iopts 1}
        {* -certfile iopts 1}
        {* -cipher iopts 1}
        {* -ciphersuites iopts 1}
        {* -command iopts 1}
        {* -dhparams iopts 1}
        {* -key iopts 1}
        {* -keyfile iopts 1}
        {* -password iopts 1}
        {* -post_handshake iopts 1}
        {* -request iopts 1}
        {* -require iopts 1}
        {* -securitylevel iopts 1}
        {* -autoservername discardOpts 1}
        {* -server iopts 1}
        {* -servername iopts 1}
        {* -session_id iopts 1}

        {* -ssl2 iopts 1}
        {* -ssl3 iopts 1}
        {* -tls1 iopts 1}
        {* -tls1.1 iopts 1}
        {* -tls1.2 iopts 1}
        {* -tls1.3 iopts 1}
        {* -validatecommand iopts 1}
        {* -vcmd iopts 1}
    }

    # tls::socket and tls::init options as a humane readable string
    variable socketOptionsNoServer
    variable socketOptionsServer

    # Internal [switch] body to validate options

	log 1 "tls::_accept error: ${::errorInfo}"
	close $chan
	error $err $::errorInfo $::errorCode
    } else {
	log 2 "tls::_accept - called \"$callback\" succeeded"
    }
}

#
# Sample callback for hooking: -
#
# error
# verify
# info
#
proc tls::callback {option args} {
    variable debug

    #log 2 [concat $option $args]

    switch -- $option {
	"error" {
	    foreach {chan msg} $args break

	    log 0 "TLS/$chan: error: $msg"
	}
	"info" {
	    # poor man's lassign
	    foreach {chan major minor msg type} $args break

	    if {$msg != ""} {
		append state ": $msg"
	    }
	    # For tracing
	    upvar #0 tls::$chan cb
	    set cb($major) $minor

	    log 2 "TLS/$chan: $major/$minor: $state"
	}
	"message" {
	    # poor man's lassign
	    foreach {chan direction version content_type msg} $args break

	    log 0 "TLS/$chan: info: $direction $msg"
	}
	"session" {
	    foreach {chan session_id ticket lifetime} $args break

	    log 0 "TLS/$chan: session: lifetime $lifetime"
	}
	default	{
	    return -code error "bad option \"$option\":\
		    must be one of error, info, or session"
	}
    }
}

#
# Sample callback when return value is needed
#
proc tls::validate_command {option args} {
    variable debug

    #log 2 [concat $option $args]

    switch -- $option {
	"alpn" {
	    foreach {chan protocol match} $args break

	    log 0 "TLS/$chan: alpn: $protocol $match"
	}
	"hello" {
	    foreach {chan servername} $args break

	    log 0 "TLS/$chan: hello: $servername"
	}
	"sni" {
	    foreach {chan servername} $args break

	    log 0 "TLS/$chan: sni: $servername"
	}
	"verify" {
	    # poor man's lassign
	    foreach {chan depth cert rc err} $args break

	    array set c $cert

	    if {$rc != "1"} {
		log 1 "TLS/$chan: verify/$depth: Bad Cert: $err (rc = $rc)"
	    } else {
		log 2 "TLS/$chan: verify/$depth: $c(subject)"
	    }
	    if {$debug > 0} {
		return 1;	# FORCE OK
	    } else {
		return $rc
	    }
	}













	default	{
	    return -code error "bad option \"$option\":\
		    must be one of alpn, info, or verify"
	}
    }
    return 1
}

proc tls::xhandshake {chan} {
    upvar #0 tls::$chan cb

    if {[info exists cb(handshake)] && \
	$cb(handshake) == "done"} {
	return 1
    }
    while {1} {
	vwait tls::${chan}(handshake)
	if {![info exists cb(handshake)]} {
	    return 0
	}
	if {$cb(handshake) == "done"} {
	    return 1
	}
    }
}

proc tls::password {rwflag size} {
    log 0 "TLS/Password: did you forget to set your passwd!"
    # Return the worlds best kept secret password.
    return "secret"
}

proc tls::log {level msg} {
    variable debug