implement “enable” (like GNU bash) to stop Harzilein from complaining

about mksh’s “rename” builtin

dot.mkshrc

@@ -1,5 +1,5 @@
 # $Id$
-# $MirOS: src/bin/mksh/dot.mkshrc,v 1.92 2015/03/08 22:54:33 tg Exp $
+# $MirOS: src/bin/mksh/dot.mkshrc,v 1.93 2015/03/08 23:50:00 tg Exp $
 #-
 # Copyright (c) 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010,
 #		2011, 2012, 2013, 2014, 2015
@@ -381,6 +381,197 @@ function setenv {
 	\eval "'export' \"$1\""'="$2"'
 }
 
+# toggle built-in aliases and utilities, and aliases and functions from here
+function enable {
+	\builtin typeset doprnt=0 mode=1 x y z rv=0
+	\builtin typeset b_alias i_alias i_func nalias=0 nfunc=0 i_all
+	\set -A b_alias
+	\set -A i_alias
+	\set -A i_func
+
+	# accumulate mksh built-in aliases, in ASCIIbetical order
+	i_alias[nalias]=autoload; b_alias[nalias++]='\builtin typeset -fu'
+	i_alias[nalias]=functions; b_alias[nalias++]='\builtin typeset -f'
+	i_alias[nalias]=hash; b_alias[nalias++]='\builtin alias -t'
+	i_alias[nalias]=history; b_alias[nalias++]='\builtin fc -l'
+	i_alias[nalias]=integer; b_alias[nalias++]='\builtin typeset -i'
+	i_alias[nalias]=local; b_alias[nalias++]='\builtin typeset'
+	i_alias[nalias]=login; b_alias[nalias++]='\exec login'
+	i_alias[nalias]=nameref; b_alias[nalias++]='\builtin typeset -n'
+	i_alias[nalias]=nohup; b_alias[nalias++]='nohup '
+	i_alias[nalias]=r; b_alias[nalias++]='\builtin fc -e -'
+	i_alias[nalias]=source; b_alias[nalias++]='PATH=$PATH:. \command .'
+	i_alias[nalias]=stop; b_alias[nalias++]='\kill -STOP'
+	i_alias[nalias]=type; b_alias[nalias++]='\builtin whence -v'
+
+	# accumulate mksh built-in utilities, in definition order, even ifndef
+	i_func[nfunc++]=.
+	i_func[nfunc++]=:
+	i_func[nfunc++]='['
+	i_func[nfunc++]=alias
+	i_func[nfunc++]=break
+	i_func[nfunc++]=builtin
+	i_func[nfunc++]=cat
+	i_func[nfunc++]=cd
+	i_func[nfunc++]=chdir
+	i_func[nfunc++]=command
+	i_func[nfunc++]=continue
+	i_func[nfunc++]=echo
+	i_func[nfunc++]=eval
+	i_func[nfunc++]=exec
+	i_func[nfunc++]=exit
+	i_func[nfunc++]=export
+	i_func[nfunc++]=false
+	i_func[nfunc++]=fc
+	i_func[nfunc++]=getopts
+	i_func[nfunc++]=global
+	i_func[nfunc++]=jobs
+	i_func[nfunc++]=kill
+	i_func[nfunc++]=let
+	i_func[nfunc++]='let]'
+	i_func[nfunc++]=print
+	i_func[nfunc++]=pwd
+	i_func[nfunc++]=read
+	i_func[nfunc++]=readonly
+	i_func[nfunc++]=realpath
+	i_func[nfunc++]=rename
+	i_func[nfunc++]=return
+	i_func[nfunc++]=set
+	i_func[nfunc++]=shift
+	i_func[nfunc++]=suspend
+	i_func[nfunc++]=test
+	i_func[nfunc++]=times
+	i_func[nfunc++]=trap
+	i_func[nfunc++]=true
+	i_func[nfunc++]=typeset
+	i_func[nfunc++]=ulimit
+	i_func[nfunc++]=umask
+	i_func[nfunc++]=unalias
+	i_func[nfunc++]=unset
+	i_func[nfunc++]=wait
+	i_func[nfunc++]=whence
+	i_func[nfunc++]=bg
+	i_func[nfunc++]=fg
+	i_func[nfunc++]=bind
+	i_func[nfunc++]=mknod
+	i_func[nfunc++]=printf
+	i_func[nfunc++]=sleep
+	i_func[nfunc++]=domainname
+
+	# accumulate aliases from dot.mkshrc, in definition order
+	i_alias[nalias]=l; b_alias[nalias++]='ls -F'
+	i_alias[nalias]=la; b_alias[nalias++]='l -a'
+	i_alias[nalias]=ll; b_alias[nalias++]='l -l'
+	i_alias[nalias]=lo; b_alias[nalias++]='l -alo'
+	i_alias[nalias]=doch; b_alias[nalias++]='sudo mksh -c "$(\builtin fc -ln -1)"'
+	i_alias[nalias]=rot13; b_alias[nalias++]='tr abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ nopqrstuvwxyzabcdefghijklmNOPQRSTUVWXYZABCDEFGHIJKLM'
+	i_alias[nalias]=cls; b_alias[nalias++]='\builtin print -n \\033c'
+
+	# accumulate functions from dot.mkshrc, in definition order
+	i_func[nfunc++]=hd
+	i_func[nfunc++]=chpwd
+	i_func[nfunc++]=cd_csh
+	i_func[nfunc++]=dirs
+	i_func[nfunc++]=popd
+	i_func[nfunc++]=pushd
+	i_func[nfunc++]=smores
+	i_func[nfunc++]=Lb64decode
+	i_func[nfunc++]=Lb64encode
+	i_func[nfunc++]=Lbafh_init
+	i_func[nfunc++]=Lbafh_add
+	i_func[nfunc++]=Lbafh_finish
+	i_func[nfunc++]=Lstripcom
+	i_func[nfunc++]=setenv
+	i_func[nfunc++]=enable
+
+	# collect all identifiers, sorted ASCIIbetically
+	\set -sA i_all -- "${i_alias[@]}" "${i_func[@]}"
+
+	# handle options, we don't do dynamic loading
+	while \getopts "adf:nps" x; do
+		case $x {
+		(a)
+			mode=-1
+			;;
+		(d)
+			# deliberately causing an error, like bash-static
+			;|
+		(f)
+			\builtin print -u2 enable: dynamic loading not available
+			\return 2
+			;;
+		(n)
+			mode=0
+			;;
+		(p)
+			doprnt=1
+			;;
+		(s)
+			\set -sA i_all -- . : break continue eval exec exit \
+			    export readonly return set shift times trap unset
+			;;
+		(*)
+			\builtin print -u2 enable: usage: \
+			    "enable [-adnps] [-f filename] [name ...]"
+			return 2
+			;;
+		}
+	done
+	\shift $((OPTIND - 1))
+
+	# display builtins enabled/disabled/all/special?
+	if (( doprnt || ($# == 0) )); then
+		for x in "${i_all[@]}"; do
+			y=$(\alias "$x") || y=
+			[[ $y = "$x='\\builtin whence -p $x >/dev/null || (\\builtin print mksh: $x: not found; exit 127) && \$(\\builtin whence -p $x)'" ]]; z=$?
+			case $mode:$z {
+			(-1:0|0:0)
+				\print -r -- "enable -n $x"
+				;;
+			(-1:1|1:1)
+				\print -r -- "enable $x"
+				;;
+			}
+		done
+		\return 0
+	fi
+
+	for x in "$@"; do
+		z=0
+		for y in "${i_alias[@]}" "${i_func[@]}"; do
+			[[ $x = "$y" ]] || \continue
+			z=1
+			\break
+		done
+		if (( !z )); then
+			\builtin print -ru2 enable: "$x": not a shell builtin
+			rv=1
+			\continue
+		fi
+		if (( !mode )); then
+			# disable this
+			\alias "$x=\\builtin whence -p $x >/dev/null || (\\builtin print mksh: $x: not found; exit 127) && \$(\\builtin whence -p $x)"
+		else
+			# find out if this is an alias or not, first
+			z=0
+			y=-1
+			while (( ++y < nalias )); do
+				[[ $x = "${i_alias[y]}" ]] || \continue
+				z=1
+				\break
+			done
+			if (( z )); then
+				# re-enable the original alias body
+				\alias "$x=${b_alias[y]}"
+			else
+				# re-enable the original utility/function
+				\unalias "$x"
+			fi
+		fi
+	done
+	\return $rv
+}
+
 \: place customisations below this line
 
 for p in ~/.etc/bin ~/bin; do