Re: [PATCH v2 3/3] golang/xenlight: add necessary module/package documentation

[George Dunlap <George.Dunlap@xxxxxxxxxx>]

> On May 13, 2020, at 1:58 AM, Nick Rosbrook <rosbrookn@xxxxxxxxx> wrote:
> 
> Add a README and package comment giving a brief overview of the package.
> These also help pkg.go.dev generate better documentation.
> 
> Also, add a copy of the LGPL (the same license used by libxl) to
> tools/golang/xenlight. This is required for the package to be shown
> on pkg.go.dev and added to the default module proxy, proxy.golang.org.

OK, so didn’t notice this at first.  It looks like you read the comments at the 
top of libxl.c, noticed the comment about “...the special exception on linking 
described in file LICENSE”, looked around for such a file, and found it in 
tools/ocaml, and copied that one?

I had a chat with Ian Jackson on IRC (copied below for the record), and think 
that comment is simply in error.  We agreed that we should just copy 
https://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt into the directory 
verbatim.

 -George

12:49:40           gwd | Hmm... libxl is supposedly under the LGPL, but I can't 
  
                       | seem to find a copy of it in our source tree           
  
12:50:01           gwd | Oh, there's one in tools/libxc                         
  
12:54:44           gwd | Diziet: The comment at the top of libxl.c refers to    
  
                       | "...the special exception on linking described in file 
  
                       | LICENSE."  But there's no such file in tools/libxl     
  
12:55:22           gwd | The most plausible candidate for what it's talking 
about 
                       | is tools/ocaml/LICENSE                                 
  
12:59:43        Diziet | Weird                                                  
  
13:00:16        Diziet | That text is present in                                
  
                       | c5c301ac774d8cb36ccbc775bb7f1d7005d78a71 "libxenlight: 
  
                       | initial libxenlight implementation under tools/libxl"  
  
13:00:39        Diziet | There is no file LICENSE other than                    
  
                       | xen/tools/figlet/LICENSE                               
  
13:00:57        Diziet | Which is a copy of the Artistic License and not        
  
                       | relevant.                                              
  
13:01:18        Diziet | However,                                               
  
13:01:43        Diziet | | Licensing Exceptions (the relaxed BSD-style license) 
  
13:01:47        Diziet | ^ in the top-level COPYING                             
  
13:02:30        Diziet | I don't think this is an "exception on linking" and it 
  
                       | doesn't state that it applies to libxl.                
  
13:03:29        Diziet | The phrase "exception on linking" appears only in 
libxl  
                       | in thta commit                                         
  
13:04:05        Diziet | 
https://github.com/xapi-project/xen-api/blob/master/ocam 
                       | l/idl/datamodel.ml                                     
  
13:04:31        Diziet | 
https://github.com/xapi-project/xen-api/blob/master/LICE 
                       | NSE                                                    
  
13:04:40        Diziet | I think that is probably what was intended to be       
  
                       | referred to.                                           
  
13:05:24        Diziet | And indeed that text appears in tools/ocaml            
  
13:06:59        Diziet | This is an additional permission (borrowing GPLv3      
  
                       | terminology) which a downstream can drop.              
  
13:07:39        Diziet | Furthermore I don't think anyone's S-o-b for a libxl   
  
                       | commit can be taken to have meant to include that      
  
                       | exception.  So I conclude that no exception in fact    
  
                       | applies and the text referring to it should be 
deleted.  
13:07:53        Diziet | gwd: ^                                                 
  
13:13:29           --> | zhengc (~zhengc@180.110.50.11) has joined #xendevel    
 
13:17:55           <-- | zhengc (~zhengc@180.110.50.11) has quit (Ping timeout: 
  
                       | 258 seconds)                                           
  
13:28:11           gwd | Diziet: OK -- this came up actually in the context of  
  
                       | "[PATCH v2 3/3] golang/xenlight: add necessary         
  
                       | module/package documentation"                          
  
13:28:48           gwd | golang has this automatic package proxy / cataloging   
  
                       | system                                                 
  
13:29:24           gwd | To have it work the way he wants it, the 
golang/xenlight 
                       | directory needs something that their system can        
  
                       | recognize as a suitable license                        
  
13:30:20           gwd | v1 had the GPL, which was just wrong; it looks like 
he's 
                       | then followed the same path I did, looking at libxl.c, 
  
                       | trying to find this "exception" thing, and copying the 
  
                       | file f/ tools/ocaml                                    
  
13:30:58           gwd | I guess I should tell him to just copy                 
  
                       | https://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt 
  
13:31:37        Diziet | y