Re: [Qemu-devel] [PATCH v2] curl: refuse to open URL from HTTP server without range support

[Richard W.M. Jones]

On Mon, Jun 17, 2013 at 07:02:00PM +0800, Fam Zheng wrote:
> On Mon, 06/17 11:54, Richard W.M. Jones wrote:
> > On Mon, Jun 17, 2013 at 06:09:23PM +0800, Fam Zheng wrote:
> > > +    if (real_size >= strlen(accept_len)
> > 
> > What's accept_len?  This patch gives me a couple of compile errors:
> > 
> Oops, a copy&paste mistake. I meant this:
> 
> +    if (realsize >= strlen(accept_line)

I added this fix and tested it against a Python HTTP server (which
does not support ranges):

$ cd /tmp
$ python -m SimpleHTTPServer

[in another window ...]

$ http_proxy= ./qemu-io -r http://127.0.0.1:8000/test1.img -c 'read -v 0 512'
CURL: Error opening file: Server not supporting range.
qemu-io: can't open device http://127.0.0.1:8000/test1.img
no file open, try 'help open'

[against another server which does support ranges ...]

$ LD_LIBRARY_PATH=~/d/curl/lib/.libs http_proxy= ./qemu-io -r 
http://libguestfs.org/index.html -c 'read -v 0 512'
00000000:  3c 21 44 4f 43 54 59 50 45 20 68 74 6d 6c 20 50  ..DOCTYPE.html.P
[etc]

By the way I think it would be better if the error message said
"Server does not support 'range' (byte ranges)."

Rich.

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