# Created: Sat Feb 24 00:17:49 EST 2001
# Name: path-funcs-sh, path-funcs
# Copyright 2001-2007, Chris F.A. Johnson
# Released under the terms of the GNU General Public License

## Functions to manipulate the PATH variable

path() ## add arguments to PATH; if no arguments, show PATH
{ 
    if [ -n "$*" ]
    then
      addpath "$@"
    else
      IFS=: eval "printf \"%s\n\" \$PATH"
    fi
}

addpath() { # add directory or directories to $PATH
    ap_prefix=0
    ap_quiet=0
    OPTIND=1
    while getopts iq var
    do
      case "$var" in
          i) ap_prefix=1 ;;
          q) ap_quiet=1 ;;
      esac
    done
    shift $(( $OPTIND - 1 ))

    for p in "$@"
    do
      p=${p%"${p##*[!/]}"} ## remove trailing slashes
      case $p in
          ""|.) continue ;;
      esac
      case :$PATH: in
          *:$p:*) [ $ap_quiet -eq 0 ] && echo "addpath: $p already in path" >&2
                  continue
              ;;
      esac
      if [ -d "$p" ]
      then
          if [ $ap_prefix -eq 1 ]
          then
              PATH="$p:$PATH"
          else
              PATH="$PATH:$p"
          fi
      else
          [ $ap_quiet -eq 0 ] && echo "addpath: $p is not a directory" >&2
      fi
    done
    export PATH
 }
 

checkpath() # verify that all entries in $PATH are directories; remove dupes
{
    verbose=0
    OPTIND=1
    while getopts  v var
    do
      case "$var" in
          v) verbose=1 ;;
      esac
    done

    ## assign the elements in PATH to the positional parameters
    oldIFS=$IFS
    IFS=":"
    set -- $PATH
    IFS=$oldIFS

    newPATH=
    for p
    do
      case $p in
          ""|.) continue ;; ## do not allow current directory
      esac

      if [ -d "$p" ]
      then
        p=${p%"${p##*[!/]}"} ## remove trailing slashes
        case :$newPATH: in
            *:"$p":*) [ $verbose -ge 1 ] &&
                echo "checkpath: removing $p (already in PATH)" >&2
                ;;
            *) newPATH=${newPATH:+$newPATH:}$p ;;
        esac
      else
          [ $verbose -ge 1 ] &&
             echo "checkpath: $p is not a directory; removing it from PATH" >&2
      fi
    done
    export PATH=$newPATH
    return
}

rmpath() # remove directory or directories from $PATH
{
    for p in "$@"
    do
      p=${p%"${p##*[!/]}"} ## remove trailing slashes
      case $PATH in
          "$p":*) PATH=${PATH#$p:} ;; ## at beginning of PATH
          *:"$p") PATH=${PATH%:$p} ;; ## at end of PATH
          *:"$p":*) PATH=${PATH%":$p"*}${PATH##*"$p"} ;;
      esac
    done
    export PATH
}