# This ruby program will patch the linker executable (link.exe)
# so that linker warning LNK4099 is ignorable.
#
# Reference: http://www.bottledlight.com/docs/lnk4099.html

require "fileutils"

def link_exes()
    res = []
    res << File.join(ENV["VS90COMNTOOLS"], "../../VC/bin/link.exe") if ENV["VS90COMNTOOLS"]
    res << File.join(ENV["VS100COMNTOOLS"], "../../VC/bin/link.exe") if ENV["VS100COMNTOOLS"]
    res << File.join(ENV["XEDK"], "bin/win32/link.exe") if ENV["XEDK"]
    return res
end

def patch_link_exe(exe)
    data = nil
    File.open(exe, "rb") {|f| data = f.read}
    unpatched = [4088, 4099, 4105].pack("III")
    patched = [4088, 65535, 4105].pack("III")

    if data.scan(patched).size > 0
        puts "* Already patched #{exe}"
        return
    end

    num_unpatched = data.scan(unpatched).size
    raise "Multiple patch locations in #{exe}" if num_unpatched > 1
    raise "Patch location not found in #{exe}" if num_unpatched == 0

    offset = data.index(unpatched)
    puts "* Found patch location #{exe}:#{offset}"
    bak = exe + "-" + Time.now.strftime("%y%m%d-%H%M%S") + ".bak"
    puts "  Creating backup #{bak}"
    FileUtils.cp(exe, bak)
    puts "  Patching exe"
    data[offset,unpatched.size] = patched
    File.open(exe, "wb") {|f| f.write(data)}
    return true
end

link_exes.each do |exe|
    patch_link_exe(exe)
end