bugfix: reading binary profile data on windows (#1906)

On Windows, we ran into the problem that the execution of inherited profiles would (sometimes) not work. This was due to the use of `File.read` and `File.write` and handling inside the file provider, which works in most cases (especially *nix systems), but does not behave as expected on Windows. A better and more correct way of treating these files is via binary read and write mode, which changes the underlying encoding of both strings that are passed along.

Signed-off-by: Dominik Richter <dominik.richter@gmail.com>

lib/inspec/file_provider.rb

@@ -24,10 +24,21 @@ module Inspec
     def initialize(_path)
     end
 
+    # Read the contents of a file. This will typically refer to a text
+    # file reading a string.
+    #
+    # @param _file [String] path of the file to be read
+    # @return [String] contents of the file described
     def read(_file)
       raise "#{self} does not implement `read(...)`. This is required."
     end
 
+    # Provide a method for reading binary contents from a file.
+    # It will default to #read if not defined. For most streams that implement
+    # it, it will be the same. For some special cases, it will add change the
+    # way in which encoding of the returned data structure is handled.
+    alias binread read
+
     def files
       raise "Fetcher #{self} does not implement `files()`. This is required."
     end
@@ -65,6 +76,12 @@ module Inspec
       return nil unless File.file?(file)
       File.read(file)
     end
+
+    def binread(file)
+      return nil unless files.include?(file)
+      return nil unless File.file?(file)
+      File.binread(file)
+    end
   end
 
   class ZipProvider < FileProvider
@@ -163,6 +180,10 @@ module Inspec
       parent.read(abs_path(file))
     end
 
+    def binread(file)
+      parent.binread(abs_path(file))
+    end
+
     private
 
     def get_prefix(fs)

lib/inspec/profile.rb

@@ -37,7 +37,7 @@ module Inspec
       cache = file_provider.files.find_all do |entry|
         entry.start_with?('vendor')
       end
-      content = Hash[cache.map { |x| [x, file_provider.read(x)] }]
+      content = Hash[cache.map { |x| [x, file_provider.binread(x)] }]
       keys = content.keys
       keys.each do |key|
         next if content[key].nil?
@@ -47,7 +47,7 @@ module Inspec
 
         FileUtils.mkdir_p tar.dirname.to_s
         Inspec::Log.debug "Copy #{tar} to cache directory"
-        File.write(tar.to_s, content[key].force_encoding('UTF-8'))
+        File.binwrite(tar.to_s, content[key])
       end
     end