#!/usr/bin/env osh
:
: osh - " Force sh(1), csh(1), and other shells to exit w/ error! " <'' ;;;
:
: "  @(#)$Id: 9c9ff6d084a2e3af077da58b0e2137f5c904dae5 $  "
:
: "  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 [-v]  "
:

: " Check for correct usage. "
: >>$0'' <'' ; : >>$1'' <'' ; killer $0 oshlatest
if $# -ne 0 -a ! \( $# -eq 1 -a X$1 = X-v \) if { exit } pusage $0 '"[-v]"'

trap	''	2 3
setenv	OSHDIR	/tmp/oshlatest-$$
umask	0077

if ! { fd2 which which >/dev/null } if { exit } perror $0 '"which: Not found"'
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''
if $# -ne 1 -a X$1 != X-v goto WGET

	:
	: " Be verbose; write shell version to standard output. "
	:
	shift
	if { fd2 -f/dev/null -- osh -c version </dev/null >VersionVerbose }
	if ! -s VersionVerbose if ! { fd2 -ef/dev/null which uname } \
		if { echo $v } goto WGET
	if ! -s VersionVerbose if   { fd2 -ef/dev/null which uname } \
		osh -c 'echo -n $v \( ; uname -srm ^ tr -d \\n ; echo \)'
	if   -s VersionVerbose cat <VersionVerbose
	: fallthrough

:
: " 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 'if ' ; \
  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 -10 >PatchCompare ; goto PC1
: set	D	'-v' ; : " DEBUG    "
set	D	''   ; : " NO DEBUG "
echo $v         ^ grep -- '-p[1-9]'  >/dev/null
if $? -eq 1 echo false               >VersionIsPatched
head -1 <LATEST ^ grep -- '-p[1-9],' >/dev/null
if $? -eq 1 echo false               >LatestIsPatched
if ! { osh $D VersionIsPatched } -a ! { osh $D LatestIsPatched } exit
if   { osh $D VersionIsPatched } -a ! { osh $D LatestIsPatched } exit
if ! { osh $D VersionIsPatched } -a   { osh $D LatestIsPatched } \
	if { exit } false

: PC1
( \
  echo -n 'if ' ; \
  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 -10 >IsLatestOrNewer ; goto EXEC
: set	D	'-v' ; : " DEBUG    "
set	D	''   ; : " NO DEBUG "
if X$v = X -o X$v = Xv                           if { exit } false
if X$v = Xosh-current                            exit
if ! { osh $D VersionCompare }                   if { exit } false
if   { expr //$v : '//.*-current' >/dev/null }   exit
if   { expr //$v : '//.*-beta[1-9]' >/dev/null } exit
if ! { osh $D PatchCompare }                     if { exit } false
if   { osh $D PatchCompare }                     exit
perror oshlatest '"IsLatestOrNewer: Unexpected condition"' ; kill -9 $$

: EXEC
: set	D	'-v' ; : " DEBUG    "
set	D	''   ; : " NO DEBUG "
if { osh $D 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"'