#!/bin/sh
#
# name    : /secure/rotate_log
#
# History :  
#       Original release 0.8 from Steven C. Simmons
#	Changes by Sean Boran:
#       <1> V1.1 May.11'93 (Sean Boran)
#	<2> V1.2 Nov.29'93
#	    Use gzip instead of compress
#       <2bis> see <2> 13.12.93 defined path to gzip
#       <3> Oct.20'96 : Removed warning "Missing backup log....Continuing"
#       <4> Nov.15'99 : Set defaults, remove logcheck offsets.
#       <5> Dec.16'99 : Send Kill -1 AFTER creating new empty log
#       <6> Feb.26'01 : chown path, use .gz not .Z
#       <7> Aug.11'01 : define PATH for gzip
#       <8> Jan.21'02 : Restart syslog with pid file in many locations
#       By jesus.martin-bernardo@vodafone.com:
#       <9> Feb.05'03 : Define a path to gzip with '-c' on command line
#                       rather than use value of COMPRESS
#
# Function:  see also man page.
#
# Shell script to rotate a log.  Usage:
#
# rotate_log log [ -L src_dir ] [ -n n ] [ -c [gzip dir]] [-s] [ -B backup_dir ]
#	[ -b backup_name ] [ -m mode ] [ -o owner ] [ -g group ]
#	[ -M mode ] [ -O owner ] [ -G group ] [ -e prolog_cmd ]
#	[ -E postlog_cmd ] logfile
#
# where the switches mean:
#
#  -L	Name of the directory 'log' is found in.
#  -n	Number of backup copies to keep.
#  -s	Skip empty logs.
#  -c   Compress the backup copy.  You can add a path to the gzip file<9>
#  -B   Dir to keep the backup copies in.
#  -b   Name of backup copy. 
#  -m   Mode of new log.
#  -o   Owner of new log (only root can use this option).
#  -g   Group of new log (only root can use this option).
#  -M   Mode of backup copy.
#  -O   Owner of backup copy (only root can use this option).
#  -G   Group of backup copy (only root can use this option).
#  -e	Command to be executed immediately before copying the logfile.
#  -E	Command to be executed immediately after copying the logfile.
#
# Stylistic note -- any error that says 'Unexpected error' means I
# thought this particular error can't happen.
#
# This program is Copyright 1989, Steven C. Simmons.  It may be freely
# redistributed provided this notice remains intact and any changes you
# make are clearly marked as such.
#
# $Source: /home/lokkur/scs/src/rotate_log/rotate_log/RCS/rotate_log,v $
#
# Revision 0.9 Feb.05'03  14:30:00 <9>
# Added to -c: You can define a path to gzip
# Fixed bug: Define COMPRESS="", until now the script compress allways
#
# $Revision: 0.8 $
#
# $Author: scs $	$Date: 91/08/02 19:01:20 $
#
# $State: Exp $	$Locker:  $
#
# $Log:	rotate_log,v $
# Revision 0.8  91/08/02  19:01:20  scs
# Corrected error in paraterization of chmod/chgrp/chown.  Didn't
# this get fixed once before?
# 
# Revision 0.7  91/04/30  22:10:10  scs
# Added -s switch.
# 
# Revision 0.6  91/04/27  16:16:59  scs
# Fixed bug with -b/-n combo losing arguements.  Patch supplied by
# Michael Bredeweg (...clif!comnet!mike).
# 
# Revision 0.5  91/04/03  19:49:00  scs
# Parameterized locations of chmod, chgrp, chown.
# ###################################################################3

SCRIPT=`basename $0`
#
# PATH: to allow this script to run on several machines, I define a
#       a PATH to be able to find gzip. <7>
PATH="/usr/bin:/bin:/usr/local/bin"; export PATH
#
#  Commonly used commands
#
#COMPRESS=""
#COMPRESS="/usr/local/bin/gzip ";
COMPRESS="gzip ";
MV=/bin/mv
CP=/bin/cp
CHMOD=/bin/chmod
CHOWN=/bin/chown
CHGRP=/bin/chgrp
#
#  Assign default values as needed <4>
#
#SOURCE_DIR=""
SOURCE_DIR="/var/log/"
SOURCE_NAME=""
BACKUP_NAME=""
BACKUP_DIR=""
BACKUP_COUNT="3"
SOURCE_MODE="640"
SOURCE_OWNER=""
SOURCE_GROUP=""
BACKUP_MODE="440"
BACKUP_OWNER=""
BACKUP_GROUP=""
#SKIP_FLAG="false"
SKIP_FLAG="true"

# Restart syslog properly, or as best we can <8>
if [ -f /etc/syslog.pid ] ; then
  CMD_AFTER="kill -1 `cat /etc/syslog.pid`"
elif [ -f /var/run/syslog.pid ] ; then
  CMD_AFTER="kill -1 `cat /var/run/syslog.pid`"
else
  CMD_AFTER="`pkill -1 syslogd`"
fi

#
#  Basic switch parsing.  Right now, this forces us to use whitespace
#  between switch char and actual execution.  Whenever we get data
#  for a switch, errorcheck it immediately.
#
while [ "$#" -gt "0" ] ; do
	case $1 in
	-L )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a directory name.  Aborting."
			exit 0
		fi
		if [ -w "${2}" -a -d "${2}" ] ; then
			:
		else
			echo "${SCRIPT}: Sorry, you cannot modify the directory ${2}.  Aborting."
			exit 0
		fi
		SOURCE_DIR="${2}/"
		shift
		;;
	-b )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a backup name.  Aborting."
			exit 0

		fi
		BACKUP_NAME="$2"
		shift
		;;
	-B )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a directory name.  Aborting."
			exit 0
		fi
		if [ -w "${2}" -a -d "${2}" ] ; then
			:
		else
			echo "${SCRIPT}: Sorry, you cannot create files in ${DIR}.  Aborting."
			exit 0
		fi
		BACKUP_DIR="${2}/"
		shift
		;;
	-n )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a backup count.  Aborting."
			exit 0
		fi
		if echo $2 | grep '[^0-9]' > /dev/null 2>&1 ; then
			echo "${SCRIPT}: The backup count ($2) must be a positive number.  Aborting."
			exit 0
		fi
		if [ $2 -eq 0 ] ; then
			echo "${SCRIPT}: The backup count ($2) must be greater than zero.  Aborting."
			exit 0
		fi
		BACKUP_COUNT="$2"
		shift
		;;
	-s )	SKIP_FLAG="true"
		;;
#	-c )	COMPRESS="compress -f"
#	-c )	COMPRESS="gzip -S .gz " # use gzip but with .Z <2>
        -c )    if [ "$2" = "" ] ; then # <9>
                       COMPRESS="gzip -S .gz " 
                else
                       if [ -d "$2" -a -x "$2/gzip" -a -r "$2/gzip"] ; then
                              COMPRESS= "$2/gzip -S .gz"
                       else
                              echo "Path to gzip is not correct"
                       fi
                fi
		shift
		;;
	-m )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a permissions mode.  Aborting."
			exit 0
		fi
		SOURCE_MODE="$2"
		shift
		;;
	-M )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a permissions mode.  Aborting."
			exit 0
		fi
		BACKUP_MODE="$2"
		shift
		;;
	-o )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires the name of the new owner.  Aborting."
			exit 0
		fi
		if grep '^${2}:' < /etc/passwd > /dev/null 2>&1 ; then
			echo "${SCRIPT}: No such login id as $2.  Aborting."
			exit 0
		fi
		SOURCE_OWNER="$2"
		shift
		;;
	-O )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires the name of the new owner.  Aborting."
			exit 0
		fi
		if grep '^${2}:' < /etc/passwd > /dev/null 2>&1 ; then
			echo "${SCRIPT}: No such login id as $2.  Aborting."
			exit 0
		fi
		BACKUP_OWNER="$2"
		shift
		;;
	-g )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires the name of the new group.  Aborting."
			exit 0
		fi
		if grep '^${2}:' < /etc/group > /dev/null 2>&1 ; then
			echo "${SCRIPT}: No such group as $2.  Aborting."
			exit 0
		fi
		SOURCE_GROUP="$2"
		shift
		;;
	-G )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires the name of the new group.  Aborting."
			exit 0
		fi
		if grep '^${2}:' < /etc/group > /dev/null 2>&1 ; then
			echo "${SCRIPT}: No such group as $2.  Aborting."
			exit 0
		fi
		BACKUP_GROUP="$2"
		shift
		;;
	-e )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a command to be executed.  Aborting."
			exit 0
		fi
		CMD_BEFORE="${2}"
		shift
		;;
	-E )	if [ "$2" = "" ] ; then
			echo "${SCRIPT}: The $1 switch requires a command to be executed.  Aborting."
			exit 0
		fi
		CMD_AFTER="${2}"
		shift
		;;
	-* )	echo "${SCRIPT}: No such switch as $1.  Aborting."
		exit 0
		;;
	* )	if [ "${SOURCE_NAME}" != "" ] ; then
			echo "${SCRIPT}: You must specify only one log file.  Aborting."
			exit 0
		else
			SOURCE_NAME=$1
		fi
		;;
	esac
	shift
done
if [ "${SOURCE_NAME}" = "" ] ; then
	echo "${SCRIPT}: You must specify a log file.  Aborting."
	exit 0
fi
#
#  Do sanity checks
#
#  If he specified a source directory or backup directory, the source
#  and backup file names cannot contain a slash.
#
if [ "${SOURCE_DIR}" != "" ] ; then
	if echo $SOURCE_NAME | grep / > /dev/null ; then
		cat << EOF
${SCRIPT}: If you specify a source directory (eg, -L ${SOURCE_DIR}),
then the log file name (${SOURCE_NAME}) must be a simple file name,
ie, not containing any slashes.  Aborting.
EOF
		exit 0
	fi
	#
	#  If they don't explicitly select a backup directory but the
	#  do specify a log directory, use the same for both.
	#
	if [ "${BACKUP_DIR}" = "" ] ; then
		BACKUP_DIR="${SOURCE_DIR}"
	fi
fi
if [ "${BACKUP_DIR}" != "" ] ; then
	if echo $BACKUP_NAME | grep / > /dev/null ; then
		cat << EOF
${SCRIPT}: If you specify a backup directory (eg, -B ${BACKUP_DIR}),
then the backup log name (${BACKUP_NAME}) must be a simple file name,
ie, not containing any slashes.  Aborting.
EOF
		exit 0
	fi
fi
#
#  Make sure we can mod the directory where the log is.
#
if [ -w `dirname "${SOURCE_NAME}"` ] ;  then
	:
else
	cat << EOF
${SCRIPT}: Sorry, you do not have permission to move/rename the
log file (file '`basename ${SOURCE_NAME}`', directory '`dirname ${SOURCE_NAME}`').  Aborting.
EOF
	exit 0
fi
#
#  Make sure we can read/write the log itself.
#
SOURCE_PATH="${SOURCE_DIR}${SOURCE_NAME}"
if [ -w "${SOURCE_PATH}" -a -r "${SOURCE_PATH}" ] ; then
	:
else
	echo "${SCRIPT}: Sorry, you do not have permission to read and modify"
	echo "the file '${SOURCE_PATH}'.  Aborting."
	exit 0
fi
#
#  If the log is empty and the skip flag (-s) is set, do nothing.
#
if [ "${SKIP_FLAG}" = "true" ] ; then
	set `wc -c ${SOURCE_PATH}`
	if [ 0 = $1 ] ; then
		exit 0
	fi
fi
#
#  Make sure root operations are only run by root
#
if [ "${BACKUP_OWNER}" != "" -o "${SOURCE_OWNER}" != "" -o "${BACKUP_GROUP}" != "" -o "${SOURCE_GROUP}" != "" ]
then
	set `who am i`
	if [ "root" != "$1" ] ; then
		echo "${SCRIPT}: Sorry, you can only change owner or group if you are root."
		echo "Aborting."
		exit 0
	fi
fi
#
#  Build the list of backup names, in reverse order.  Make them
#  full pathnames.
#
if [ "${BACKUP_NAME}" = "" ] ; then
	BACKUP_NAME="${SOURCE_NAME}"
fi
while expr $BACKUP_COUNT \> 0 > /dev/null ; do
	BACKUP_COUNT=`expr $BACKUP_COUNT - 1`
	BACKUP_FILES="${BACKUP_FILES} ${BACKUP_DIR}${BACKUP_NAME}.${BACKUP_COUNT}"
done
#
#  Rotate the existing backups.  Assume no change in permissions, etc.
#
set ${BACKUP_FILES}
if [ "${1}" = "" ] ; then
	echo "${SCRIPT}: unexpected error in using backup list.  Aborting."
	exit 0
fi
OLDEST="${1}"
NEXT="${1}"
shift
while [ "$1" != "" ] ; do
	NEXT="${1}"
	rm -f "${OLDEST}" "${OLDEST}.gz"
	if [ -f "${NEXT}" ] ; then
		${MV} "${NEXT}" "${OLDEST}"
	elif [ -f "${NEXT}.gz" ] ; then
		${MV} "${NEXT}.gz" "${OLDEST}.gz"
	else
		# <3> sb, 17.10.96: remove this pesky warning:
		#echo "${SCRIPT}: Missing backup log ${NEXT} or ${NEXT}.gz.  Continuing."
		:
	fi
	OLDEST="${NEXT}"
	shift
done
#
#  Copy the current log to be the first backup.  Use full pathnames
#  as appropriate.
#
if [ "${SOURCE_DIR}" != "" ] ; then
	if cd "${SOURCE_DIR}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error in command 'cd ${SOURCE_DIR}'.  Aborting."
		exit 0
	fi
fi
rm -f "${NEXT}" "${NEXT}.gz"
if [ "${CMD_BEFORE}" != "" ] ; then
	${CMD_BEFORE}
fi
if ${MV} "${SOURCE_NAME}" "${NEXT}" ; then
	:
else
	echo "${SCRIPT}: unexpected error making first backup.  Aborting."
	exit 0
fi

# Delete old log, create new empty one
# MAke sure this happens before sending HUP to syslog <5>
rm -f "${SOURCE_NAME}" "${SOURCE_NAME}".gz
if cat > "${SOURCE_NAME}" < /dev/null ; then
	:
else
	echo "${SCRIPT}: unexpected error emptying log file.  Continuing."
fi

#
#  Set ownership and permission on the log as requested.
#
if [ "${SOURCE_MODE}" != "" ] ; then
	if ${CHMOD} ${SOURCE_MODE} "${SOURCE_NAME}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error executing command '${CHMOD} ${SOURCE_MODE} ${SOURCE_NAME}'."
		echo "Aborting."
		exit 0
	fi
fi
if [ "${SOURCE_OWNER}" != "" ] ; then
	if ${CHOWN} ${SOURCE_OWNER} "${SOURCE_NAME}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error executing command '${CHOWN} ${SOURCE_OWNER} ${SOURCE_NAME}'."
		echo "Aborting."
		exit 0
	fi
fi
if [ "${SOURCE_GROUP}" != "" ] ; then
	if ${CHGRP} ${SOURCE_GROUP} "${SOURCE_NAME}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error executing command '${CHGRP} ${SOURCE_GROUP} ${SOURCE_NAME}'."
		echo "Aborting."
		exit 0
	fi
fi

# Typically a HUP signal is sent to syslog here
if [ "${CMD_AFTER}" != "" ] ; then
	${CMD_AFTER}
        ## <4>
        if [ -f ${SOURCE_NAME}.offset ] ; then
          #echo "Reset logcheck offset"
          rm -f ${SOURCE_NAME}.offset
        fi
fi


#
#  Set ownerships and permissions as requested on the backed up log.
#  Note that the compress must come last in this sequence.
#
if [ "${BACKUP_MODE}" != "" ] ; then
	if ${CHMOD} ${BACKUP_MODE} "${NEXT}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error executing command '${CHMOD} ${BACKUP_MODE} ${NEXT}'."
		echo "Aborting."
		exit 0
	fi
fi
if [ "${BACKUP_OWNER}" != "" ] ; then
	if ${CHOWN} ${BACKUP_OWNER} "${NEXT}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error executing command '${CHOWN} ${BACKUP_OWNER} ${NEXT}'."
		echo "Aborting."
		exit 0
	fi
fi
if [ "${BACKUP_GROUP}" != "" ] ; then
	if ${CHGRP} ${BACKUP_GROUP} "${NEXT}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error executing command '${CHGRP} ${BACKUP_GROUP} ${NEXT}'."
		echo "Aborting."
		exit 0
	fi
fi
if [ "${COMPRESS}" != "" ] ; then
	if ${COMPRESS} "${NEXT}" ; then
		:
	else
		echo "${SCRIPT}: unexpected error executing command '${COMPRESS} ${NEXT}'."
		echo "Aborting."
		exit 0
	fi
fi
#eof