From: Jos Backus <jos@...>
Date: 2004-05-09T03:13:09+09:00
Subject: Re: Ruby Installer for Windows: use of Win32OLE bug causes crash

--yrj/dFKFPuw6o+aM
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline

On Sat, May 08, 2004 at 06:48:54PM +0900, Shashank Date wrote:
> 
> "Jos Backus" <jos@catnook.com> wrote in message
> > Oops, I forgot to mention that the specific line I'm removing is EMPTY.
> And I
> > can reproduce this in different parts of the source file. It's definitely
> > vertical whitespace-related. Oddest bug I've seen in a while.
> 
> Strange ! Which line is that ?

There are a few positions in the file where this happens. Starting from the
bottom I can "move" the empty line I'm deleting up and get the same error, but
it doesn't work near the top of the file. I'm assuming the bug is such that
Ruby needs to have seen a declaration of a particular kind before the problem
manifests itself. In the attached file, which works in its current form on 2K3
I was able to trigger the problem arbitrarily by extending some of the string
constants beyond a certain length or removing expression terms (e.g. 1 * 1 ->
1) in addition to changing the vertical whitespace (horizontal whitespace
seemed to have no influence). I saw the line issue at line 74 in the attached
file, and the first problem occurred when I tried adding an "align" => "right"
argument to a cgi.td call. But I'd be surprised if you could duplicate the
subtle failures 2K3 showed on XP, as I wasn't able to.

It sure would be nice to hear the win32ole author pipe up.

> -- shanko

-- 
Jos Backus                       _/  _/_/_/      Sunnyvale, CA
                                _/  _/   _/
                               _/  _/_/_/
                          _/  _/  _/    _/
jos at catnook.com        _/_/   _/_/_/          require 'std/disclaimer'

--yrj/dFKFPuw6o+aM
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment; filename="diskspace_noerror.rb"

require 'win32ole'
require 'cgi'
require 'stringio'

outputfilename = "NUL.aaaa"

hosts = []
File.open("dhhhhhhhhhhh.txt").each_line do |line|

  foo = ""
  hosts << line.chomp
end

hosts = %w(localhost localhost localhost localhost)

class DiskInfo
  attr_reader :deviceid, :size, :freespace
  def initialize(deviceid, size=1, freespace=1)
     @deviceid, @size, @freespace = deviceid, size, freespace
  end
  def p
     1 + 1
  end
end


def get_diskinfo(host)
  result = []
  result << DiskInfo.new('')
  result << DiskInfo.new('')
  result = []
  begin
    wmi = WIN32OLE.connect("winmgmts://#{host}/root/cimv2")
  rescue
    return nil
  end
  disks = wmi.ExecQuery("Select * from Win32_LogicalDisk")
  disks.each do |disk|
  
    next if disk.Size.nil?
    next if disk.Size.to_i == 0 and disk.FreeSpace.to_i == 0
    result << DiskInfo.new(disk.DeviceID, disk.Size.to_i, disk.FreeSpace.to_i)
  end
  result
end


def alert_color(value)
   case value
   when 10...20;  ""
   when 5...10;   ""
   when 0...5;     ""
   else raise
   end
end

diskdata = hosts.collect do |host|
  [ host, get_diskinfo(host) ]
end

cgi = CGI.new("html4")
cgi.out {
  diskdata.collect { |host, di|
		  di.collect { |disk|
                    cgi.tr {
                               cgi.td { "" } +
                               cgi.td { "" } +
                               cgi.td { "" } +
			       cgi.td { "" }
			}
		  }
	}
}

File.open(outputfilename, "w") do |file|
  foo = "" + ""
end


exit

File.open(outputfilename, "w") do |file|
  foo = ""
  bar = ""
  
  cgi = CGI.new("html4")
  cgi.out {
     cgi.html {
        cgi.head { "" + cgi.title{"                "} } +
        cgi.body { "" +
           cgi.h2 { "                        " } +
	   cgi.p { "" + Time.now.to_s } +
           cgi.table {
              cgi.tr { cgi.th({"width" => "    ", "alig" => "le"}) { "Host" } + cgi.th { "Disk" } + cgi.th { "Total" } + cgi.th { "Free" } + cgi.th { "%" } } +
	      diskdata.collect { |host, di|
	        unless di
		  cgi.tr { cgi.td { "" } }
	        else
		  di.collect { |disk|
                    cgi.tr {
                               cgi.td { "" } +
			       cgi.td { "" } +
			       cgi.td { "" / 1 * 3 } +
			       cgi.td { "" / 1 * 3 } +
			       cgi.td() { "" % disk.size }
                     }
		  }
		end
		}
	      }.join("")
           }
        }
     }


  foo = ""
  file.puts outstring.readlines[1,1]
  file.puts
  foo = "" + ""
end
--yrj/dFKFPuw6o+aM--