Fix a few CPAN issues

lib/fpm/package/cpan.rb

@@ -112,6 +112,8 @@ def input(package)
     self.vendor = case metadata["author"]
       when String; metadata["author"]
       when Array; metadata["author"].join(", ")
+      # for Class::Data::Inheritable and others with blank 'author' field, fix "Invalid package configuration: Unexpected CPAN 'author' field type: NilClass. This is a bug."
+      when NilClass; "No Vendor Or Author Provided"
       else
         raise FPM::InvalidPackageConfiguration, "Unexpected CPAN 'author' field type: #{metadata["author"].class}. This is a bug."
     end if metadata.include?("author")
@@ -304,7 +306,8 @@ def unpack(tarball)
     directory = build_path("module")
     ::Dir.mkdir(directory)
     args = [ "-C", directory, "-zxf", tarball,
-      "--strip-components", "1" ]
+     #      "--strip-components", "1" ]       # fails    on removing leading ./Foo/ in tarball paths
+            %q{--transform=s,[./]*[^/]*/,,} ]  # succeeds on removing leading ./Foo/ or /Foo/ or Foo/
     safesystem("tar", *args)
     return directory
   end

lib/fpm/util.rb

@@ -153,9 +153,10 @@ def execmd(*args)
     process.io.stdout = stdout_w
     process.io.stderr = stderr_w
 
-    if block_given? and opts[:stdin]
-      process.duplex = true
-    end
+    # Always use duplex mode because we will always
+    # want to either write to stdin (if block_given?)
+    # or we will want to close stdin to prevent subprocesses from blocking on it.
+    process.duplex = true
 
     process.start
 
@@ -170,10 +171,13 @@ def execmd(*args)
 
       yield(*args3)
 
-      process.io.stdin.close        if opts[:stdin] and not process.io.stdin.closed?
+      process.io.stdin.close        if not process.io.stdin.closed?
       stdout_r.close                unless stdout_r.closed?
       stderr_r.close                unless stderr_r.closed?
     else
+      # If no block given (not interactive) we should close stdin.
+      process.io.stdin.close
+
       # Log both stdout and stderr as 'info' because nobody uses stderr for
       # actually reporting errors and as a result 'stderr' is a misnomer.
       logger.pipe(stdout_r => :info, stderr_r => :info)