#!/bin/sh

# $Id: update-fonts-scale 2186 2005-02-11 07:11:05Z branden $

# This program generates fonts.scale files for X font directories; see
# mkfontdir(1x) for a description of the format of fonts.scale files.

# Copyright 1999-2002, 2004 Branden Robinson.
# Licensed under the GNU General Public License, version 2.  See the file
# /usr/share/common-licenses/GPL or <http://www.gnu.org/copyleft/gpl.txt>.

PROGNAME=${0##*/}

# Query the terminal to establish a default number of columns to use for
# displaying messages to the user.  This is used only as a fallback in the event
# the COLUMNS variable is not set.  ($COLUMNS can react to SIGWINCH while the
# script is running, and this cannot, only being calculated once.)
DEFCOLUMNS=$(stty size 2>/dev/null | awk '{print $2}') || true
if ! expr "$DEFCOLUMNS" : "[[:digit:]]\+$" >/dev/null 2>&1; then
    DEFCOLUMNS=80
fi

# Display a message, wrapping lines at the terminal width.
message () {
    echo "$*" | fmt -t -w ${COLUMNS:-$DEFCOLUMNS}
}

# Display a debugging message.
trace () {
    if [ -n "$DEBUG" ]; then
        message "note: $*" >&2
    fi
}

# Display a warning message.
warn () {
    message "warning: $*" >&2
}

# Display an error message and exit.
die () {
    message "fatal error: $*" >&2
    exit 1
}

# Display a usage message.
usage () {
    if [ -n "$*" ]; then
        message "usage error: $*"
    fi
    cat <<EOF
Usage: $PROGNAME DIRECTORY ...
       $PROGNAME { -h | --help }
This program combines scalable X font information from several packages into a
single file that is placed in each specified X font directory DIRECTORY.  This
utility is primarily useful to Debian package maintainer scripts.  See
update-fonts-scale(8) for more information.
Options:
    -h, --help                               display this usage message and exit
EOF
}

# Validate arguments.
case "$1" in
    -h|--help)
        usage
        exit 0
        ;;
    -*)
        usage "unrecognized option" >&2
        exit 2
        ;;
esac

if [ $# -eq 0 ]; then
    usage "one or more font directories must be specified" >&2
    exit 2
fi

while [ -n "$1" ]; do
    # Try to be clever about the argument; were we given an absolute path?
    if expr "$1" : "/.*" >/dev/null 2>&1; then
        # Yes; an absolute path to an X font directory was provided.
        XDIR=$1
        ETCDIR=/etc/X11/fonts/${XDIR##*/}
        if [ "$XDIR" = "$ETCDIR" ]; then
            # We were given an /etc directory as an argument.
            die "path to X font directory must be used"
        else
            warn "absolute path $XDIR was provided"
        fi
    else
        # No; a relative path was provided -- assume we were given just the
        # basename.
        XDIR=/usr/lib/X11/fonts/$1
        ETCDIR=/etc/X11/fonts/$1
    fi
    # Confirm that the directories to be operated on exist.
    for DIR in "$XDIR" "$ETCDIR"; do
        VALID=yes
        if ! [ -d "$DIR" ]; then
            warn "$DIR does not exist or is not a directory"
            VALID=
        fi
    done
    if [ -n "$VALID" ]; then
        # Are there any files to process?
        if [ "$(echo "$ETCDIR"/*.scale)" != "$ETCDIR/*.scale" ]; then
            for SCALEFILE in "$ETCDIR"/*.scale; do
                # Only write fonts to the .scale file that actually exist, so
                # that removed-but-not-purged scalable font packages do not
                # register nonexistent fonts; this has the desirable side effect
                # that the count at the top of the file is also omitted.
                #
                # XXX: This technique will be tricked into yielding false
                # negatives if the font filename has whitespace in it.
                while read FONTFILE FONTNAME; do
                    if [ -f "$XDIR/$FONTFILE" ]; then
                        echo "$FONTFILE $FONTNAME" \
                          >>"$XDIR/fonts.scale.update-tmp"
                    else
                        trace "$SCALEFILE references nonexistent font file" \
                          "$FONTFILE; skipping"
                    fi
                done <"$SCALEFILE"
            done
            if [ -e "$XDIR/fonts.scale.update-tmp" ]; then
                # Write the new scale file to a temporary location in case we
                # are interrupted.  Write the new count to the top of file.  Use
                # cat and pipe to wc so wc doesn't report the filename.
                cat "$XDIR/fonts.scale.update-tmp" | wc -l | tr -d '[:blank:]' \
                  >"$XDIR/fonts.scale.update-new"
                cat "$XDIR/fonts.scale.update-tmp" \
                  >>"$XDIR/fonts.scale.update-new"
                mv "$XDIR/fonts.scale.update-new" "$XDIR/fonts.scale"
                rm "$XDIR/fonts.scale.update-tmp"
            fi
        else
            # No files to process; remove any fonts.scale file already in the
            # font directory.
            rm -f "$XDIR/fonts.scale"
            # Remove the font directory if it is empty.
            rmdir "$XDIR" >/dev/null 2>&1 || true
        fi
    fi
    shift
done

exit 0

# vim:set ai et sts=4 sw=4 tw=80:
