#

# DIRECTORY MANIPULATION FUNCTIONS PUSHD, POPD AND DIRS

#

# Uses global parameters _push_max _push_top _push_stack

integer _push_max=100 _push_top=100

# Display directory stack -- $HOME displayed as ~

function dirs

{

typeset dir="${PWD#$HOME/}"

case $dir in

$HOME)

dir=\~

;;

/*) ;;

*) dir=\~/$dir

esac

print -r - "$dir ${_push_stack[@]}"

}

# Change directory and put directory on front of stack

function pushd

{

typeset dir= type=0

integer i

case $1 in

"") # pushd

if ((_push_top >= _push_max))

then print pushd: No other directory.

return 1

fi

type=1 dir=${_push_stack[_push_top]}

;;

+[1-9]|+[1-9][0-9]) # pushd +n

integer i=_push_top$1-1

if ((i >= _push_max))

then print pushd: Directory stack not that deep.

return 1

fi

type=2 dir=${_push_stack[i]}

;;

*) if ((_push_top <= 0))

then print pushd: Directory stack overflow.

return 1

fi

esac

case $dir in

\~*) dir=$HOME${dir#\~}

esac

cd "${dir:-$1}" > /dev/null || return 1

dir=${OLDPWD#$HOME/}

case $dir in

$HOME)

dir=\~

;;

/*) ;;

*) dir=\~/$dir

esac

case $type in

0) # pushd name

_push_stack[_push_top=_push_top-1]=$dir

;;

1) # pushd

_push_stack[_push_top]=$dir

;;

2) # push +n

type=${1#+} i=_push_top-1

set -- "${_push_stack[@]}" "$dir" "${_push_stack[@]}"

shift $type

for dir

do (((i=i+1) < _push_max)) || break

_push_stack[i]=$dir

done

esac

dirs

}

# Pops the top directory

function popd

{

typeset dir

if ((_push_top >= _push_max))

then print popd: Nothing to pop.

return 1

fi

case $1 in

"")

dir=${_push_stack[_push_top]}

case $dir in

\~*) dir=$HOME${dir#\~}

esac

cd "$dir" || return 1

;;

+[1-9]|+[1-9][0-9])

typeset savedir

integer i=_push_top$1-1

if ((i >= _push_max))

then print pushd: Directory stack not that deep.

return 1

fi

while ((i > _push_top))

do _push_stack[i]=${_push_stack[i-1]}

i=i-1

done

;;

*) print pushd: Bad directory.

return 1

esac

unset '_push_stack[_push_top]'

_push_top=_push_top+1

dirs

}