CVS branch name from tag name

Question

I have a number of modules in CVS with different tags. How would I go about getting the name of the branch these tagged files exist on? I've tried checking out a file from the module using cvs co -r TAG and then doing cvs log but it appears to give me a list of all of the branches that the file exists on, rather than just a single branch name.

Also this needs to be an automated process, so I can't use web based tools like viewvc to gather this info.

Answer 1

I have the following Korn functions that you might be able to adjust to run in bash. It should be apparent what it's doing.

Use get_ver() to determine the version number for a file path and given tag. Then pass the file path and version number to get_branch_name(). The get_branch_name() function relies on a few other helpers to fetch information and slice up the version numbers.

get_ver()
{
    typeset FILE_PATH=$1
    typeset TAG=$2
    TEMPINFO=/tmp/cvsinfo$$

    /usr/local/bin/cvs rlog -r$TAG $FILE_PATH 1>$TEMPINFO 2>/dev/null

    VER_LINE=`grep "^revision" $TEMPINFO | awk '{print $2}'`
    echo ${VER_LINE:-NONE}
    rm -Rf $TEMPINFO 2>/dev/null 1>&2
}


get_branch_name()
{
    typeset FILE=$1
    typeset VER=$2

    BRANCH_TYPE=`is_branch $VER`

    if [[ $BRANCH_TYPE = "BRANCH" ]]
    then
        BRANCH_ID=`get_branch_id $VER`
        BRANCH_NAME=`get_tags $FILE $BRANCH_ID`
        echo $BRANCH_NAME
    else
        echo $BRANCH_TYPE
    fi
}



get_minor_ver()
{
    typeset VER=$1

    END=`echo $VER | sed 's/.*\.\([0-9]*\)/\1/g'`
    echo $END
}

get_major_ver()
{
    typeset VER=$1

    START=`echo $VER | sed 's/\(.*\.\)[0-9]*/\1/g'`
    echo $START
}

is_branch()
{
    typeset VER=$1
    # We can work out if something is branched by looking at the version number.
    # If it has only two parts (i.e. 1.123) then it's on the trunk
    # If it has more parts (i.e. 1.2.2.4) then it's on the branch
    # We can error detect if it has an odd number of parts

    POINTS=`echo $VER | tr -dc "." | wc -c | awk '{print $1}'`
    PARTS=$(($POINTS + 1))

    if [[ $PARTS -eq 2 ]]
    then
        print "TRUNK"
    elif [[ $(($PARTS % 2)) -eq 0 ]]
    then
        print "BRANCH"
    else
        print "ERROR"
    fi
}

get_branch_id()
{
    typeset VER=$1

    MAJOR_VER=`get_major_ver $VER`
    MAJOR_VER=${MAJOR_VER%.}

    BRANCH_NUMBER=`get_minor_ver $MAJOR_VER`

    BRANCH_POINT=`get_major_ver $MAJOR_VER`

    echo ${BRANCH_POINT}0.${BRANCH_NUMBER}
}

get_tags()
{
    typeset FILE_PATH=$1
    typeset VER=$2

    TEMP_TAGS_INFO=/tmp/cvsinfo$$

    cvs rlog -r$VER $FILE_PATH 1>${TEMP_TAGS_INFO} 2>/dev/null

    TEMPTAGS=`sed -n '/symbolic names:/,/keyword substitution:/p' ${TEMP_TAGS_INFO} | grep ": ${VER}$" | cut -d: -f1 | awk '{print $1}'`
    TAGS=`echo $TEMPTAGS | tr ' ' '/'`
    echo ${TAGS:-NONE}
    rm -Rf $TEMP_TAGS_INFO 2>/dev/null 1>&2
}