Re: [Qemu-devel] [PATCH] block.c: fix real cdrom detection

[Laurent Vivier <lvivier@redhat.com>]

On 25/06/2015 17:48, Paolo Bonzini wrote:
> 
> On 25/06/2015 17:32, Programmingkid wrote:
>>> I think we are going to have to agree to disagree. I have never
>>> used the /dev/sr(0 | 1) devices and don't see how they would be
>>> effected by this patch. Are you trying to say the /dev/sr(0 | 1)
>>> devices *should* be handled by this patch?
>>
>> Thinking about your question some more, I see what you mean. On Linux
>> /dev/sr0 refers to the cdrom drive. Also on Linux, the /dev/cdrom
>> link refers to the /dev/sr0 device file. So if you just use
>> /dev/cdrom, you are good.
> 
> Well, that's not how things work.
> 
> If you do things like that, you end up with a bunch of hacks, not with a
> decent piece of software.
> 
> There is support for CD-ROM passthrough on Linux and FreeBSD in
> block/raw-posix.c.  Perhaps the FreeBSD support can be extended to OS X
> as well.
> 

In fact, programmingkid, you should fix it in hdev_open() where there is
already a #if __APPLE__ .

Paolo, I agree with you but :

hdev_open()

#if defined(__linux__)
    {
        char resolved_path[ MAXPATHLEN ], *temp;

        temp = realpath(filename, resolved_path);
        if (temp && strstart(temp, "/dev/sg", NULL)) {
            bs->sg = 1;
        }
#endif

I'm wondering who had this strange idea... :)

Laurent