Re: [libvirt] libvirt boolean type
At Fri, 11 Jan 2013 16:11:35 +0000,
Daniel P. Berrange wrote:
[Daniel, I meant to send my reply to the list on Friday. Maybe it got
stuck somewhere or I had only sent it to you alone - I was using a
different MUA using a Live-CD... Sorry for the duplicate, if any.]
On Fri, Jan 11, 2013 at 04:40:31PM +0100, Claudio Bley wrote:
> Hi.
>
> The following patch's intend is to get a discussion started first.
>
> Rationale:
>
> Many functions in libvirt return "1 for <TRUE>, 0 for <FALSE> and
-1
> on <ERROR>".
>
> When calling a function you need to read the documentation, skipping
> to the "Returns:" text in order to determine what return values to
> expect from the function and how to interpret them.
>
> This is cumbersome and takes an extra step which could be avoided.
>
> Advantages:
>
> + enum is binary compatible with int, so no ABI changes
I'm afraid that is wrong. Size of enums is undefined in C. The compiler
is free to use any integer size to represent an enum. As such we have a
rule that no enums are allowed in libvirt API signatures.
That's too bad. This surely diminishes the value of this addition (a
bit).
Nonetheless, I think it still would be valuable as point 2 and 3 still
hold. Just change the definition to:
typedef int virBool;
Claudio
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