#!/bin/sh
# @(#) generate md5sum for commited files
#
# Copyright (c) 2009 Dirk Jagdmann <doj@cubic.org>
# https://llg.cubic.org/tools/cvsmd5.html
#
# This software is provided 'as-is', without any express or implied
# warranty. In no event will the authors be held liable for any damages
# arising from the use of this software.
#
# Permission is granted to anyone to use this software for any purpose,
# including commercial applications, and to alter it and redistribute it
# freely, subject to the following restrictions:
#
#     1. The origin of this software must not be misrepresented; you
#        must not claim that you wrote the original software. If you use
#        this software in a product, an acknowledgment in the product
#        documentation would be appreciated but is not required.
#
#     2. Altered source versions must be plainly marked as such, and
#        must not be misrepresented as being the original software.
#
#     3. This notice may not be removed or altered from any source
#        distribution.
#
# Version: 2009-12-30
#
# This script works with CVS 1.12.x or newer.
# You have to set "UseNewInfoFmtStrings=yes" in CVSROOT/config.
# Add this file to your CVSROOT directory and add the following line to
# CVSROOT/loginfo as the first directive:
#   ALL sh $CVSROOT/CVSROOT/md5 %c %r %p %s
# Add the following line to CVSROOT/commitinfo:
#   ALL sh $CVSROOT/CVSROOT/md5 checkmd5 %r %p %s
# Add the following line to CVSROOT/posttag:
#   ALL sh $CVSROOT/CVSROOT/md5 %c %r %p %s
# Add the following line to CVSROOT/checkoutlist:
#   md5 Unable to check out md5sum script
#
##############################################################################

# set your contact information
ADR="Dirk Jagdmann <doj@cubic.org>"

# enable for debugging and development purposes
#DEBUG=1

# enable to write backup version of repository files
BACKUP=1

##############################################################################

[ "$DEBUG" ] && echo `date +%Y-%m-%dT%H:%M:%S` "$@"

# get command line arguments
CMD="$1"
REP="$2"
DIR="$3"
shift 3

ABSDIR="$REP/$DIR"
ATTIC="$ABSDIR/Attic"

# if a previous run of md5 left work to do, it stored it in the command file
#CMDFN="$ABSDIR/md5.run"
#if [ -f "$CMDFN" ] ; then
#    [ "$DEBUG" ] && echo "execute command file $CMDFN"
#    TMP=`mktemp`
#    mv -f "$CMDFN" "$TMP"
#    sh "$TMP"
#    rm -f "$TMP"
#fi

if [ "$CMD" = import ] ; then
    # go into directory
    if ! cd "$ABSDIR" ; then
	echo "md5:  could not chdir $ABSDIR"
	exit 1
    fi
    find . -name '*,v' -execdir $0 md5sum {} ';'

    [ "$DEBUG" ] && echo "md5: exit success"
    exit 0

# special action invoked by find from import
elif [ "$CMD" = md5sum ] ; then
    # get rid of ./
    FN=`echo "$REP" | cut -b 3-`
    # create md5 sum
    umask 077

    MD5="$FN.md5"
    BAK="$FN.bak"

    md5sum "$FN" > "$MD5"
    if [ "$BACKUP" ] ; then
	[ "$DEBUG" ] && echo "backup $FN -> $BAK"
	cp -fp "$FN" "$BAK"
    fi

    [ "$DEBUG" ] && echo "md5: exit success"
    exit 0
fi

for fn in "$@" ; do

    ABSDIR="$REP/$DIR"		# this might get modified below, so we have to re-set it for each loop iteration
    FN="$fn,v"
    ABSFN="$ABSDIR/$FN"
    MD5="$FN.md5"
    BAK="$FN.bak"

    if [ "$CMD" = commit -o "$CMD" = tag ] ; then
        # check for file
	if [ ! -f "$ABSFN" ] ; then
	    # check if the file moved to Attic/
	    if [ -f "$ATTIC/$FN" ] ; then
		# remove old MD5
		rm -f "$ABSDIR/$MD5"
		# re-set variables
		ABSDIR="$ATTIC"
		ABSFN="$ABSDIR/$FN"
		[ "$DEBUG" ] && echo "$FN moved to Attic"
	    else
		echo "md5: did not find file $ABSFN"
		exit 1
	    fi
	fi
        # go into directory
	if ! cd "$ABSDIR" ; then
	    echo "md5: could not chdir $ABSDIR"
	    exit 1
	fi

        # generate checksum
	[ "$DEBUG" ] && echo "md5sum $ABSDIR/$FN > $ABSDIR/$MD5"
	umask 077
	md5sum "$FN" > "$MD5"
	# check for old checksum in Attic/
	if [ ! -f "Attic/$FN" -a -f "Attic/$MD5" ] ; then
	    [ "$DEBUG" ] && echo "remove stale checksum from Attic/"
	    rm -f "Attic/$MD5"
	fi

	# generate frozen file
	if [ "$BACKUP" ] ; then
	    [ "$DEBUG" ] && echo "backup $ABSDIR/$FN -> $ABSDIR/$BAK"
	    cp -fp "$FN" "$BAK"
            # check for old backup in Attic/
	    if [ ! -f "Attic/$FN" -a -f "Attic/$BAK" ] ; then
		[ "$DEBUG" ] && echo "remove stale backup from Attic/"
		rm -f "Attic/$BAK"
	    fi
	fi

    elif [ "$CMD" = checkmd5 -a -f "$ABSFN" ] ; then
        # go into directory
	if ! cd "$ABSDIR" ; then
	    echo "md5: could not chdir $ABSDIR"
	    exit 1
	fi
	# check against md5 checksum
	if [ -f "$MD5" ] ; then
	    TMP=`mktemp`
	    md5sum "$FN" > $TMP
	    cmp "$MD5" $TMP
	    RES=$?
	    rm -f $TMP
	    [ "$DEBUG" ] && echo "cmp $ABSDIR/$MD5 $TMP := $RES"
	    if [ "$RES" != 0 ] ; then
		echo "  MD5 checksum of $ABSFN does not match! Your repository might be corrupted!"
		echo "  Contact your CVS administrator $ADR for help on this problem."
		exit 1
	    fi
	fi
    fi

done

[ "$DEBUG" ] && echo "md5: exit success"
exit 0