From: Mike Hommey <mh@glandium.org>
Date: Thu, 28 Aug 2008 18:04:52 GMT
Subject: Re: Git-aware HTTP transport
Message-ID: <20080828180452.GB14901@glandium.org>
In-Reply-To: <alpine.DEB.1.10.0808281033070.2713@asgard.lang.hm>

On Thu, Aug 28, 2008 at 10:37:04AM -0700, david@lang.hm wrote:
> On Thu, 28 Aug 2008, Shawn O. Pearce wrote:
>
>> david@lang.hm wrote:
>>> On Thu, 28 Aug 2008, Shawn O. Pearce wrote:
>>>>> "Shawn O. Pearce" <spearce@spearce.org> writes:
>>>>
>>>> Yes, I really did mean for this part of the protocol to be in binary.
>>>
>>> except that HTTP cannot transport binary data, if you feed it binary data
>>> it then encodes it into 7-bit safe forms for transport.
>>
>> So then how does it transport a GIF file to my browser?  uuencoded?
>
> something like that. it uses the mimetype mechanisms to identify the  
> various pieces and encodes each piece (if nothing else it needs to make  
> sure that the mimetype seperators don't appear in the data) uuencode is  
> one of the available mechanisms.
>
>> Last time I read the RFCs I was pretty certain HTTP is 8-bit clean
>> in both directions.
>
> I could be wrong, but I'm pretty sure I'm not. to test this yourself find 
> a webserver with an image file and retrieve it via telnet (telnet 
> hostname 80<enter>GET /path/to/file HTTP/1.0<enter><enter>) and what will 
> come back will be text.

No it won't. Try it *yourself*.

$ nc www.google.com 80 | sed '1,/^\r$/d' > /tmp/logo.gif
GET /intl/en_ALL/images/logo.gif HTTP/1.1
Host: www.google.com
Connection: close

$ file /tmp/logo.gif 
/tmp/logo.gif: GIF image data, version 89a, 276 x 110

Mike

PS: sed only removes the HTTP response headers.