#!/usr/bin/env osh
:
: osh - " Force sh(1), csh(1), and other shells to exit w/ error! " <'' ;;;
:
: "  @(#)$Id: 2328e64cf08dafcad5d8878cab68408841a29dd9 $  "
:
: "  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, or patched, release of the shell, as reported  "
: "  in http://v6shell.org/src/LATEST .                              "
:
: "  Exit w/ zero status (true) if latest, or newer than latest,     "
: "  version.  Otherwise, exit w/ 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 / ; chdir $d''

:
: " Fetch LATEST w/ wget, curl, lynx, or an ftp utility w/ HTTP support. "
:
: WGET
if ! { fd2 which wget >/dev/null } goto CURL
	wget -q http://v6shell.org/src/LATEST
	goto JUMP
: CURL
if ! { fd2 which curl >/dev/null } goto LYNX
	curl -s http://v6shell.org/src/LATEST >LATEST
	goto JUMP
: LYNX
if ! { fd2 which lynx >/dev/null } goto FTP
	lynx -dump http://v6shell.org/src/LATEST >LATEST
	goto JUMP
: FTP
if ! { fd2 which ftp >/dev/null } goto ERR1
	ftp http://v6shell.org/src/LATEST >/dev/null
	: fallthrough
: JUMP
	if ! -s LATEST goto ERR2
	: fallthrough

:
: " Create and execute comparison scripts. "
:
: VC
( \
  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' ; \
    echo ; \
) >VersionCompare

: PC
head -7 >PatchCompare ; goto PC1
echo $v         ^ grep -- '-p[1-9]'  >/dev/null
if $s = 1 echo false                 >VersionIsPatched
head -1 <LATEST ^ grep -- '-p[1-9],' >/dev/null
if $s = 1 echo false                 >LatestIsPatched
if ! { osh VersionIsPatched } -a ! { osh LatestIsPatched } exit
if   { osh VersionIsPatched } -a ! { osh LatestIsPatched } exit
if ! { osh VersionIsPatched } -a   { osh LatestIsPatched } if { exit } false

: PC1
( \
  echo -n 'intcmp ' ; \
  echo $v ^ sed -n 's/^.*-p\([1-9]\)$/\1/p' ^ tr -d \\n ; \
  echo -n ' -ge ' ; \
  head -1 <LATEST ^ sed -n 's/^.*-p\([1-9]\),.*$/\1/p' ; echo ; \
) >>PatchCompare

: ILON
head -8 >IsLatestOrNewer ; goto EXEC
if X$v = X -o X$v = Xv                           if { exit } false
if X$v = Xosh-current                            exit
if ! { osh VersionCompare }                      if { exit } false
if   { expr //$v : '//.*-current' >/dev/null }   exit
if   { expr //$v : '//.*-beta[1-9]' >/dev/null } exit
if ! { osh PatchCompare }                        if { exit } false
if   { osh PatchCompare }                        exit
perror oshlatest '"IsLatestOrNewer: Unexpected condition"' ; kill -9 $$

: EXEC
if { osh IsLatestOrNewer } goto TRUE

	which osh ^ tr -d \\n ; echo : $v: Outdated ; echo ; cat 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

: TRUE - " Is latest, or newer than latest, version! "

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

: ERR1
	chdir - ; rm -r $d''
	perror $0 \
	'"Cannot fetch LATEST - need wget, curl, lynx, or ftp w/ HTTP support"'
	exit

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