monitor fs changes with inotify-tools and invoke make automatically

maked

#!/bin/bash

interval=2
file_ignore='\.(swp|orig|old[0-9]*|bak[0-9]*)$|^core$|.*~$'
dir_ignore='(\.git|\.hg)'
make='make'

#####################################################
progname='maked'

usage () {
cat << "EOF"
Usage: $progname [OPTSIONS] [--] [MAKE_ARGS...]
  Monitor changes under current directory using inotify, and
  runs 'make'
EXAMPLE
    maked -- -n
        Run make with -n(--dry-run) option when changes are detected.
    maked --interval 10 vmlinux
        Try to build 'vmlinux' file every 10 sec, whenever change is detected.
OPTIONS
    -i, --interval=SECONDS    Minimum interval to run make.
    -e, --file-exclude=REGEX  Files to be ignored, as regular expression.
                                Default: /$file_ignore/
    -d, --dir-exclude=REGEX   Directories to be ignored, as regular expression
                                Default: /$dir_ignore/
    -m, --make=COMMAND_NAME   Specify alternative make command
    -h, --help                Show this help.
    -v, --verbose             Print detail information.
    --                        Indicate end of option, in case MAKE_ARGS starts
                                with dash(-)
EOF
}

MSG () { echo "$progname: $*"; }
DIE () { MSG "$@" >&2; exit 1; }
MSG_V () {
    if [ "$opt_verbose" = yes ]; then
        MSG "$@"
    fi
}

optparse () {
    local opt="$1"
    local arg="$2"
    local name="$3"
    case $1 in
        --*=*) eval "$name=\"${opt#*=}\""; return 1;;
        -*)   eval "$name=\"$arg\"";      return 0;;
        *) DIE "Internal Error"
    esac
}

while [ $# -ge 1 ]
do
    case $1 in
        -e|--file-exclude*) optparse "$1" "$2" file_ignore || shift;;
        -d|--dir-exclude*)  optparse "$1" "$2" dir_ignore  || shift;;
        -m|--make*)         optparse "$1" "$2" make        || shift;;
        -i|--interval*)     optparse "$1" "$2" interval    || shift;;
        -h|--help) usage; exit 0;;
        -v|--verbose) opt_verbose=yes;;
        -*) DIE "Unknown option $1" ;;
        --) break;;
    esac
    shift
done

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

last_executed=0
MSG_V "Started"
MSG_V "    interval:      $interval sec"
MSG_V "    make command:  $make"
MSG_V "    file_ignore:   $file_ignore"
MSG_V "    dir_ignore:    $dir_ignore"
inotifywait -e create -e modify -e delete -e move -r -m . 2>/dev/null |
    while read dir event file
    do
        MSG_V "Event '$event' for file '$file' in '$dir'"
        if [[ $event =~ ISDIR ]]
        then
            MSG_V "Ignoring change of '$dir'"\
                  "(changes for directories are ignored)"
        elif [[ $dir =~ $dir_ignore ]]
        then
            MSG_V "Ignoring change in '$dir': match to dir_ignore pattern"
        elif [[ $file =~ $file_ignore ]]
        then
            MSG_V "Ignoring change of '$dir': match to file_ignore pattern"
        else
            ((remain = (last_executed + interval) - SECONDS))
            if (( remain > 0 ))
            then
                MSG_V "$remain seconds to wait."
                sleep $remain
            fi
            MSG_V "Executing: $make $*"
            "$make" "$@"
            last_executed=$SECONDS
        fi
    done