#!/bin/bash -u
#% flexdial -- automatic alternate numbers dialer
VER='$Revision: 1.268 $';
#% Copyright (c) 2003 Richard Hawes <rhawes@dma.org> under GPL v. 2
#-This program is free software; you can redistribute it and/or modify
#-it under the terms of the GNU General Public License as published by
#-the Free Software Foundation; either version 2, or (at your option)
#-any later version.
#-This program is distributed in the hope that it will be useful,
#-but WITHOUT ANY WARRANTY; without even the implied warranty of
#-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#-GNU General Public License for more details.
#-You should have received a copy of the GNU General Public License
#-along with this program; if not, write to the Free Software
#-Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#_
#_		FEATURES
#_*	automatically dial alternate numbers
#_*	uses a pipe to send chat verbose messages to diald and
#_	to system logs at debug priority
#_*	uses a pipe to report connect speed to system log at info priority
#_*	messages to system log can be reduced by setting priority level
#_	while letting all messages go to diald fifo
#_
#_		AVAILABILITY
#_Available at www.dma.org/~rhawes/programs/flexdial
#_GPL Available at www.dma.org/~rhawes/site/COPYING
#_
#_		SECURITY
#_This program exports password variables to chat
#_instead of passing passwords on the command line.
#_Command lines can be seen in /proc and with ps -fC chat.
#_Run as another user:
#_connect "/bin/su -pc '/etc/flexdial/flexdial -n \"522-002 412-449\"' dialout"
#_
#_		PREFIXES
#_All names begin with an underscore (_) or a single letter and underscore.
#_User defined variables and functions should use a different
#_prefix to avoid conflicts with future versions.
#_
#_		COMMENTS
#_	To remove comments:
#_perl -e 'while(<>){s/\s*#[-_=].*$//;print if length > 1;}' flexdial
#_	To view documentation:
#_grep '#[%_=]' < flexdial | sed -e 's/#[%_]//' -e 's/#[=]/(default)/'
#_
#_		SYNOPSIS
#_Usage: flexdial -d (print commands) -f `configuration_file'
#_	-n `list of phone numbers' -o `eval string'
#_
#_any variable can be changed with -o 'variable=value'
#_Directory for configuration files.
_CFG_DIR=/etc/flexdial; #=
#_configuration file suffix
_CFG_SFX="sh"; #=
#_
#_		REQUIREMENTS
#_This script requires the use of chat-1.9 or greater for full
#_functionality. It should work with older versions of chat,
#_but it will not be able to report the reason for a connection failure.
#_This was tested on Bash version 2.05a.0(1)-release
#_
#_		ERROR CODES
#_The error code indicates either a configuration error,
#_the number of the last successfully completed phase,
#_or terminating on a signal
readonly E_CFG=2 E_SIG=4;
#_		UNCONNECTED PHASES
#_The modem is in command mode.
readonly P_ON_HK=10 P_OFF_HK=11 P_WAIT=12;
#_Phase numbers 32-63 RESERVED for user defined phases.
#_		CONNECTED PHASES (>=64)
#_The modem is in online mode.
#_It can know when to escape to command mode with escape sequence before
#_giving the hangup command. (Remote system will not be sent `AT'.)
readonly P_CONN=64 P_LOGIN=65 P_CALLBK=66;
#_Phase numbers 96-127 RESERVED for user defined phases.
#_
#_
#_*=	^	^	^	^	^	^	=*
#_		CONFIGURATION FILE
#_Has a default suffix of .sh for file browsers
#_*=	v	v	v	v	v	v	=*
#_
#_set to a non empty string to remove fifo's
_CLEAN_UP=""; #=
#_
#_date format for messages sent to diald fifo
_DATE="-Iseconds"; #=
#_
#_Set Dial Prefix to T for touch tone or P for Pulse dialing
_DIAL=T; #=
#_Use it to specify other commands such as dialing an outside line.
#_For example, to dial 9, wait for dial tone(`W') use:
#__DIAL=T9W
#_
#_escape modem to command mode
#_modem registers:
#_S2=escape character
#_S12=guard time
_ESCAPE='\d\d\d\d\d+++\c'; #=
#_
#_shell eval strings
#_Use this to let PPP authentify you:
_EVAL_AFTER=':'; #=
#_
#_Use this to login:
#_pwd=xyz;
#__EVAL_AFTER='_log_in 60 name pwd'
#_
#_An example of using callback:
#__EVAL_AFTER='_log_in 60 name pwd&&_call_back 20&&
#__phase_if 96 "start ppp" _chat 15 "annex:" ppp&&
#__phase_if 97 ack _chat 15 PPP "\c"'
#_
#_commands before dialing
_EVAL_BEFORE=':'; #=
_EVAL_BEGIN=':'; #=
#_to redirect error path to debug pipe use:
#__EVAL_BEGIN='exec 2>&$D_debug;';
_EVAL_END=':'; #=
_EVAL_ERROR=':'; #=
#_
#_If diald fifo is set up, it is used to send all messages
#_to a diald monitoring program such as dctrl.
#_Set to "" to avoid warnings if diald is not used.
_FIFO_DIALD=/var/run/diald.fifo; #=
#_
#_set suffix to null to use files instead of fifos.
_FIFO_SUFF=.fifo; #=
#_
#_commands to hash
_HASH="chat date logger mkdir mknod rm"; #=
#_
#_logger facility (see man 8 syslog-facility)
_LOG_FACILITY=user; #=
#_logger tag
_LOG_TAG="flexdial[$$]"; #=
#_
#_The initialization string for your modem
_INITIAL='AT&FV1W2E0S12=249'; #=
#_
#_space separated list of phone numbers
_PHONE_NOS=""; #=
#_
#_signals to trap
_SIGNALS='HUP INT TERM'; #=
#_
#_How long to wait for modem to connect
_TIMEOUT=90; #=
#_
#_prefix for temporary files or fifos
_TMP_PREF=flexdial; #=
#_
#_working directory and fifo location
_TMP_DIR=/var/tmp/flexdial; #=
#_
#_
#_*=	^	^	^	^	^	^	=*
#_		FUNCTIONS
#_To use these functions,
#_put shell command list in the variable `_EVAL_AFTER'
#_*=	v	v	v	v	v	v	=*
#_
#_	_call_back `optional timeout in seconds'
_call_back () {
	_hang_up $P_WAIT;
	_phase_if $P_CALLBK "call back" _modem ${1:-90} RING ATA;
}
#_
#_	_chat `timeout in seconds' chat script
_chat () { r_chat $_CHAT '' "$@";}
#_
#_	_do command list
#_do command and print error message if it fails
_do () { { "$@" >&$D_debug 2>&1;}||_err "$* failed!";}
#_
#_	_err "message string"
#_sends err priority messages
_err () { e_exit w $p_val "$@";}
#_
#_	_hang_up `optional phase #'
_hang_up () {
	#-put modem in comand mode
	#-then hang up
	[ $p_val -ge $P_CONN ]&&m_esc||:;
	m_at||m_esc||:;
	m_h&&_phase ${1:-$P_ON_HK} "modem hung up"||
	_warn "could not hang up modem";
}
#_
#_	_info "message"
_info () { _write info "$@";}
#_
#_	_log_in `timeout in seconds' `user name' `name of pwd var'
#_Log in to provider.
#_Password passed thru environment instead of command line (more secure).
#_The chat sequence to recognize that the remote system
#_is asking for your user name.
_SEQ_LOGIN='ogin--ogin'; #=
#_The chat sequence to recognize that the remote system
#_is asking for your password.
_SEQ_PWD=assword; #=
_log_in () {
	_phase_if $P_LOGIN login	\
	_secret "$3" $1			\
		"$_SEQ_LOGIN" "$2"	\
		"$_SEQ_PWD" "\q\$$3"	;
}
#_
#_	_modem `timeout in seconds' chat script
#_sends commands to modem
_modem () {
	local M_TO=$1;shift;
	r_chat r_debug '' $M_TO	ABORT ERROR	"$@"||{
		set -- $?;
		case $1 in
			4) return 0;;
			*) return $1;;
		esac
	}
}
#_
#_	_open `fd #' `file'
_open () { [ "$2" ]&&{ eval exec "$1>$2"||_warn "cannot open fd $1 to $2";} }
#_
#_	_priority `priority level'
#_	priority levels are the same key words as syslog priority
#_	*	err		: error conditions
#_	*	warning		: warning conditions
#_	*	notice		: normal, but significant, condition
#_	*	info		: informational message
#_	*	debug		: debug-level message
#_
#_	_phase `phase #' ["optional message"]
_phase () {
	p_val=$1;shift;
	[ $# -lt 1 ]||_write notice "$@";
}
#_
#_	_phase_if `phase #' `phase msg' command list
#_if command succeeds, set next phase
_phase_if () {
	local P_NO=$1 P_MG=$2;shift 2;
	{ "$@";}&&_phase $P_NO "$P_MG succeeded!"||
	_warn "$P_MG failed!";
}
_priority () {
	set +u
	eval V_LVL=\$X_$1;
	set -u;
	case "$V_LVL" in
		[$X_err-$X_debug]);;
		*)	V_LVL=$X_debug;
			e_cfg "no such priority level '$1' ";;
	esac
}
#_
#_	_report [info|debug|off]
_report () {
	case "$1" in
		info|debug|off)	_CHAT="r_$1";;
		*)	e_cfg "$1 invalid report mode";;
	esac
}
#_
#_	_secret 'export list' `timeout in seconds' chat script
_secret () { r_chat r_debug "$@";}
#_
#_	_write priority "message string" < messages
#_Pass a message on to diald and the system logs.
_write () {
	local _PRI="$1" _COM=":" _MSG;
	eval [ $V_LVL -lt "\$X_$1" ]||_COM=logger;
	shift;
	_MSG="$*";
	{
	while true; do
		[ -z "$_MSG" ]||{
			echo -E "message `date $_DATE` $_LOG_TAG: $_MSG" >&$D_DIALD;
			echo -E "$_MSG";
		}
		read -r _MSG||break;
	done
	}|$D_C $_COM -p "$_LOG_FACILITY.$_PRI" -t "$_LOG_TAG";
}

#_
#_	_verbose [y|n]
#_select chat verbose mode
_verbose () {
	case "$1" in
		y*)	_VERBOSE="-vsS";;
		n*)	_VERBOSE="";;
		*)	e_cfg "$1 is invalid _verbose mode";;

	esac
}
#_
#_	_warn "warning message" and fail and or list
_warn () { _write warning "$@"; return $p_val;}


D_C="";
d_check () {
	echo "flexdial $2"
	D_C="echo -E";
	eval exec "$D_DIALD>&4";
}


e_cfg () { e_exit w $E_CFG "$@";}
E_EXIT=0; #-prevent endless error loops
e_exit () {
	local _W=$1 _E=$2;shift 2;
	[ $E_EXIT -eq 0 ]&&{
		E_EXIT=$_E;
		_write err "$@";
		_hang_up;
		e_eval _EVAL_ERROR;
	}||:;
	f_exit $_W $E_EXIT;
}
e_eval () { { eval eval \"\$${1}\";}||_err "eval string $1 failed";}
e_sig () { e_exit s $E_SIG "terminating on $1";}
e_trap () { while [ $# -gt 0 ]; do trap "e_sig $1" $1;shift;done;}
e_v () { e_cfg "flexdial $2";}
	

A_Finfo="";
A_Fdebug="";
f_log () {
        local _FIL;
        eval _FIL=\"\$A_F$1\";
        [ -f "$_FIL" ]&&{
                _write $1 < "$_FIL";
        }
}
f_exit () {
	set +x;
	f_close;
	e_eval _EVAL_END;
	[ "${_FIFO_SUFF}" ]||{ f_log info;f_log debug;}
	[ -z "$_CLEAN_UP" ]||{
		[ "$1" = w ]&&wait;
		_do rm -f "$A_Finfo" "$A_Fdebug";
	}
	exit $2;
}
f_fifo () {
	{ [ -p "$2" ]||_do mknod --mode=0660 "$2" p;
	}&&[ -w "$2" ]&&{
		(set +x;_priority debug;_write $1;) <$2 &
	}||_warn "cannot open fifo '$2' for logging";
}
f_file () {
	local _PIP;
	_PIP="${_TMP_PREF}.${_LOG_FACILITY}.${1}${_FIFO_SUFF}";
	eval A_F$1=\"$_PIP\";
	{ [ -z "${_FIFO_SUFF}" ]||f_fifo $1 $_PIP;}&& eval _open \$D_$1 $_PIP;
}
f_close () { eval exec ">&4 2>&4 $D_DIALD>&5 $D_info>&4 $D_debug>&4";}


m_at () { _modem 5	'' ''	'' 'AT'		'OK-AT-OK' '\c';}
m_dial () {
	_phase $P_OFF_HK "Dialing $1";
	_chat	$_TIMEOUT	\
		REPORT	CONNECT		\
		ABORT	ERROR		\
		ABORT	BUSY		\
		ABORT	"NO ANSWER"	\
		ABORT	VOICE		\
		ABORT	"NO DIALTONE"	\
		""	"ATD$_DIAL$1"	\
		CONNECT	'\c'		;
}
m_esc () { _chat 15	'' "$_ESCAPE"		OK '\c';}
m_h () { _modem 5	'' ATH		OK '\c';}
m_init () {
	m_at||_err "Failed to attention the modem";
	_modem	5	'' "$_INITIAL"	OK '\c'\
	||_err "Failed to initialize the modem";
}


r_chat () {
	local F_CH="$1" L_EXP="$2" M_TO="$3" C_ST=0;shift 3;
	[ -z "$L_EXP" ]||export $L_EXP;
	$F_CH $M_TO ABORT "\r\nNO CARRIER\r\n" "$@"||C_ST=$?;
	[ -z "$L_EXP" ]||export -n $L_EXP;
	case $C_ST in
		0) ;;
		1) e_cfg "Chat Error";;
		2) e_cfg "Chat Script Error";;
		3) _info "Chat Timeout";;
		4) _info "No Carrier";;
		#- provided abort strings are in this order
		5) e_cfg "bad modem command";;
		6) _info "Busy";;
		7) _info "No Answer";;
		8) _info "Voice";;
		9) _err "No Dial Tone";;
		*) _err "chat error: $C_ST";;
	esac
	return $C_ST;
}
r_debug () { $D_C chat $_VERBOSE -Et "$@" <&3 >&3 2>&$D_debug;}
r_info () { $D_C chat -r "$A_Finfo" $_VERBOSE -Et "$@" <&3 >&3 2>&$D_debug;}
r_off () { $D_C chat -r /dev/null $_VERBOSE -Et "$@" <&3 >&3 2>&$D_debug;}


#-priority levels
readonly X_err=3 X_warning=4 X_notice=5 X_info=6 X_debug=7;


#-		MAIN PROGRAM

_CFG="";
readonly D_DIALD=6 D_info=7 D_debug=8;
exec 3<&0 3>&1 4>&2 5<>/dev/null 0<&5;
f_close;
_phase $P_ON_HK;
_priority info;
_report info;
_verbose no;
e_trap ERR;
while getopts :df:n:o: _OPT;do case $_OPT in
	d)	d_check $VER;;
	f)	_CFG="$OPTARG";;
	n)	_PHONE_NOS="$OPTARG";;
	o)	e_eval OPTARG;;
	:)	e_cfg "option '-$OPTARG' missing an argument";;
	\?)	e_cfg "invalid option: -$OPTARG";;
esac;done
if [ "$_CFG" ];then
	shift $(($OPTIND - 1));
	OPTIND=1;
	_do cd "$_CFG_DIR";
	F_CF="${_CFG}.${_CFG_SFX}";
	source "./$F_CF" "$@"||e_cfg "sourcing $_CFG_DIR/$F_CF failed"
fi
hash $_HASH||e_cfg "hash error, PATH=$PATH";
$D_C _open $D_DIALD $_FIFO_DIALD||:;
[ "$_PHONE_NOS" ]||e_cfg "no phone numbers";
[ -d "$_TMP_DIR" ]||$D_C _do mkdir --mode=0770 "$_TMP_DIR";
$D_C _do cd "$_TMP_DIR";
e_trap $_SIGNALS;
$D_C f_file info||:;
$D_C f_file debug||:;
e_eval _EVAL_BEGIN;
for N_PHONE in $_PHONE_NOS;do
	m_init;
	e_eval _EVAL_BEFORE;
	! m_dial $N_PHONE||{
		_phase $P_CONN&&eval "$_EVAL_AFTER&&f_exit w 0||:";
	}
	[ $E_EXIT -eq 0 ]||exit $E_EXIT;
	_hang_up||break;
done
_err "all numbers failed";