Re: [Libguestfs] [libnbd PATCH 1/3] generator: Introduce REnum/RFlags return types
On 9/7/20 9:13 AM, Richard W.M. Jones wrote:
> +++ b/generator/C.ml
> @@ -66,15 +66,15 @@ let errcode_of_ret =
> function
> | RBool | RErr | RFd | RInt | RInt64 | RCookie -> Some "-1"
> | RStaticString | RString -> Some "NULL"
> - | RUInt -> None (* errors not possible *)
> + | RUInt | REnum (_) | RFlags (_) -> None (* errors not possible *)
>
> let type_of_ret =
> function
> - | RBool | RErr | RFd | RInt -> "int"
> + | RBool | RErr | RFd | RInt | REnum (_) -> "int"
This is good because Enum is passed as int.
> [...]
You used unsigned for RFlags, but shouldn't it be this instead?
+ | RFlags (_) -> "uint32_t"
Hmm. For Flags as input, we take uint32_t, but for get_handshake_flags
which used to return RUint, we returned unsigned; as written, my patch
preserved generated code in its entirety. Changing it to return
uint32_t makes sense, but is a minor API change. Fortunately, it would
not be an ABI change on any of the platforms we compile on. So I can go
ahead and return the smarter type unless we have a strong reason not to
(the API change might affect anyone that was storing a function pointer
to nbd_get_handshake_flags, and more so in C++ than C).
The rest of the patch looks fine.
Rich.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3226
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