@echo off
rem  InstallLatestCygwinSnapshot.bat
rem  A combined bat/perl script to automatically install the latest snapshot.
rem  Requires Cygwin perl and wget on your path.

rem Run the perl script part, which is at the end.
perl -x -- %0

if ERRORLEVEL 1 goto :error1

rem  Replace cygwin1.dll
cd c:\unix\bin
del cygwin1.dll
ren deleteme.dll cygwin1.dll
echo Done.
pause
exit

:error1
echo Error.
pause
exit 1

rem -------------------- PERL STARTS HERE -----------------
#!/bin/perl
# My sweet LORD perl is cool!

use File::Temp qw/ tempfile tempdir /;

# Get the snapshots page
print "Getting list of snapshots...\n";
$page = `wget -O- http://cygwin.com/snapshots/ 2>/dev/null`;

if ($?)
{
	die "Couldn't get list of snapshots";
}

# Parse the URLs out of it.
(@base) = ($page =~ m|(http.*cygwin-inst.*bz2)|gm);

# Sort them by date, newest to oldest.
@base = sort {$b cmp $a} @base;

# Get the newest one.
$URL = @base[0];
($BASENAME) = (@base[0] =~ m!([^/]*bz2$)!);

print "Latest snapshot is ", $BASENAME, "\n";

# Download the file
print "Downloading ", $URL, "...\n";
system("wget -cq -nd --directory-prefix=/. $URL") == 0
	or die "Couldn't download file";

# Create a temp dir for extractiong cygwin1.dll
$tempdir = tempdir( CLEANUP => 1);

# Extract as much as we can (i.e. hopefully everything except cygwin1.dll)
# Extract *only* the cygwin1.dll, to a different name in /bin, and we'll move
# it to its final resting place back in cmd.exe.
print "Extracting...\n";
system("cd / &&
	tar -xjf $BASENAME --exclude=usr/bin/cygwin1.dll &&
	cp $BASENAME $tempdir/$BASENAME &&
	cd $tempdir &&
	tar -xjf $BASENAME usr/bin/cygwin1.dll &&
	cp usr/bin/cygwin1.dll /bin/deleteme.dll") == 0
	or die "Extraction failed";