Script for updating Portage files in Sabayon

sync-entropy-files.sh

#!/bin/bash

# sync-entropy-files.sh
# Copyright Reuben D'Netto 2014. Published under Apache 2.0 license.
# This script updates the portage files used in Sabayon so that entropy and portage don't step on each other's feet

BUILD_DIR="/var/cache/sabayon-build"
ARCH=$(uname -m)
[[ "$ARCH" == "i686" || "$ARCH" == "x86_64" ]] && ARCH="intel"

# Generates filenames for config file protection
function protect {
    DIR=$(dirname $1)
    FILE=$(basename $1)

    for i in `seq 0 9999`; do
        PROTECTED_FILE=$(printf "%s/._cfg%.4i_%s" $DIR $i $FILE)
        [ -f "$PROTECTED_FILE" ] || return
    done

    echo "Too many config protection files: $i" >&2
    exit 1
}

# Pull latest files from github
if [ -d $BUILD_DIR ]; then
    OLD_HEAD=$(git -C $BUILD_DIR rev-parse HEAD)
    git -C $BUILD_DIR pull || exit 1
else
    git clone "https://github.com/Sabayon/build.git" $BUILD_DIR || exit 1
    git -C $BUILD_DIR config --add branch.master.rebase true
fi

if [ ! -d $BUILD_DIR/conf/$ARCH ]; then
    echo "Unknown architecture '$ARCH'." >&2
    exit 1
fi

# Update files
echo "Updating Sabayon portage files..."
cd $BUILD_DIR/conf/$ARCH/portage

for file in * */* */*/* ; do
    if [ -f "/etc/portage/$file" -a -f "$file" ]; then
        if ! cmp -s "/etc/portage/$file" "$file"; then
            protect "/etc/portage/$file"
            cp -n $file $PROTECTED_FILE
        fi

    elif [ -f $file ]; then
        echo "WARNING: Skipping $file" >&2
    fi
done

if [ ! -z "$BUILD_DIR" ]; then
    echo ""
    echo "Sabayon portage file changes:"

    if [ "${OLD_HEAD}" != "${HEAD}" ]; then
        git -C $BUILD_DIR log --oneline ${OLD_HEAD}..HEAD -- conf
    else
        echo "(none)"
    fi

    echo ""
fi

# Don't need to notify the user, because emerge will do that for us (when called from eix-sync)

Fixed some issues.
HEAD was not defined and the pager didn't work well with eix-sync.
https://gist.github.com/0a0da4476b6d1cf68e72.git