[Libguestfs] [libnbd PATCH 1/2] generator: Refactor handling of closures in unlocked functions

[Eric Blake]

On 9/8/20 8:57 AM, Richard W.M. Jones wrote:

>> diff --git a/generator/C.ml b/generator/C.ml
>> index deb77fa..280b319 100644
>> --- a/generator/C.ml
>> +++ b/generator/C.ml
>> @@ -99,16 +99,17 @@ let rec name_of_arg = function
>>   | UInt64 n -> [n]
>>
>>   let rec print_arg_list ?(wrap = false) ?maxcol ?handle ?types ?(parens = true)
>> +          ?(closure_mark) args optargs =
> 
> You don't need parens around here, you can just write ?closure_mark

Leftovers from when I tried to initialize the default here, before 
realizing...

> 
>> +  if parens then pr "(";
>> +  if wrap then
>> +    pr_wrap ?maxcol ','
>> +      (fun () -> print_arg_list' ?handle ?types ?closure_mark args optargs)
>> +  else
>> +    print_arg_list' ?handle ?types ?closure_mark args optargs;
>> +  if parens then pr ")"
>> +
>> +and print_arg_list' ?(handle = false) ?(types = true) ?(closure_mark = "")

...it actually needed to be here.

> ...
>>             args optargs =
>>         | Closure { cbname; cbargs } ->
>>            if types then pr "nbd_%s_callback " cbname;
>> -         pr "%s_callback" cbname
>> +         pr "%s%s_callback" closure_mark cbname
> 
> Perhaps make it type safe?
> 
>    type closure_mark = AddressOf | Dereference

It's a tri-state: Direct (empty string, for public API and elsewhere we 
don't need decoration), AddressOf (when calling into internal function 
from the public API, to decorate with &), and Derereference (when 
declaring the internal function, to decorate with *).  But yes, that 
seems a little cleaner than an open-coded string.

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3226
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