#!/usr/bin/env osh
:
: osh - " Force sh(1), csh(1), and other shells to exit w/ error! " <'' ;;;
:
: "  @(#)$Id: oshlatest.osh 540 2008-11-01 15:56:51Z jneitzel $  "
:
: "  The author of this file, J.A. Neitzel <jan (at) v6shell (dot) org>,  "
: "  hereby grants it to the public domain.                               "
:

:
: "  Check the version of the shell running this script against    "
: "  the latest official release of the shell, as reported in      "
: "  http://v6shell.org/src/LATEST .                               "
:
: "  Exit with a zero status (true) if latest version or current.  "
: "  Otherwise, exit with a non-zero status (false).               "
:
: "  usage: oshlatest  "
:

: " Check for correct usage. "
: >>$0'' <''
killer $0'' oshlatest
if $n != 0 if { exit } pusage $0

sigign	+	2 3
setenv	OSHDIR	/tmp/oshlatest-$$
umask	0077

if   { fd2 which . >/dev/null } if { exit } perror $0 '"which: Invalid results"'
if ! { fd2 which osh >/dev/null } if { exit } perror $0 '"osh: Not found"'
if ! { mkdir $d'' } if { exit } false

chdir	$d''

:
: " Fetch LATEST w/ ftp, lynx, curl, or wget. "
:
: FTP
if ! { fd2 which ftp >/dev/null } goto LYNX
	ftp http://v6shell.org/src/LATEST >/dev/null
	goto JUMP
: LYNX
if ! { fd2 which lynx >/dev/null } goto CURL
	lynx -dump http://v6shell.org/src/LATEST >LATEST
	goto JUMP
: CURL
if ! { fd2 which curl >/dev/null } goto WGET
	curl -s http://v6shell.org/src/LATEST >LATEST
	goto JUMP
: WGET
if ! { fd2 which wget >/dev/null } goto ERR1
	wget -q http://v6shell.org/src/LATEST
	: fallthrough

: JUMP
if ! -s LATEST goto ERR2

:
: " Create and execute `IsLatestOrCurrent' to do the comparison. "
:
( \
  echo 'if X$v = X -o X$v = Xv if { exit } false' ; \
  echo -n 'intcmp ' ; \
  echo $v ^ \
    sed -n 's/^.*\([0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]\).*$/\1/p' ^ \
    tr -d \\n ; echo -n ' -ge ' ; \
  head -1 <LATEST ^ \
    sed -n 's/^.*\([0-9][0-9][0-9][0-9][0-9][0-9][0-9][0-9]\).*$/\1/p' \
) >IsLatestOrCurrent
: cat <IsLatestOrCurrent
if { osh IsLatestOrCurrent } goto TRUE

	which osh ^ tr -d \\n ; echo : $v: Outdated ; echo ; cat <LATEST
	rm -r $d'' ; false ; exit

: TRUE - " Looks like the latest version or current! "

	rm -r $d'' ; : zero status ; exit

: ERR1
	rm -r $d''
	perror $0 '"Cannot fetch LATEST - need ftp, lynx, curl, or wget"'
	exit

: ERR2
	rm -r $d'' ; perror $0 '"Invalid LATEST file - try again"'