[Glass] Passing a enum element to a C library

[Smalltalk at JGFoster.net]

Bruno,

I’ve entered #48867 to track this internally.

James

> On Jul 2, 2020, at 4:03 AM, bruno buzzi brassesco <smalltalk at adinet.com.uy> wrote:
> 
> James,
> Should be this reported as a bug ? Or at least a warning in documentation at chapter 18 (FFI) ?
> 
> regards,
> bruno
> 
> On 1/7/2020 23:00, Smalltalk at JGFoster.net wrote:
>> Bruno,
>> 
>> I’m glad you got it working. And you properly interpreted my first suggestion (which didn’t work). I was going to investigate a bit more before making any further suggestions, but you anticipated where I was going. I’ll look further into the problem but I’m glad you have a work-around.
>> 
>> James
>> 
>>> On Jul 1, 2020, at 6:51 PM, bruno buzzi brassesco <smalltalk at adinet.com.uy> wrote:
>>> 
>>> James,
>>> 
>>> After replacing #'prt' with #'uint32' and initializing the wrapper the C call work as expected :)
>>> Excellent !
>>> regards,
>>> bruno
>>> 
>>> On 1/7/2020 21:27, Smalltalk at JGFoster.net wrote:
>>>> It seems to me that the function should be interpreted as (#’ptr’ #’int’ #’ptr’) since an enum is simply an integer. Try passing it just 0 and see if that goes through.
>>>> 
>>>> James
>>>> 
>>>>> On Jul 1, 2020, at 4:41 PM, bruno buzzi brassesco via Glass <glass at lists.gemtalksystems.com> wrote:
>>>>> 
>>>>> Hi,
>>>>> 
>>>>> How to pass an enum element to a C library.
>>>>> C function signature:
>>>>> int ssh_options_set(ssh_session session, enum ssh_options_e type, const void *value)
>>>>> 
>>>>> The enum is defined as:
>>>>> enum ssh_options_e {
>>>>>  SSH_OPTIONS_HOST,
>>>>>  SSH_OPTIONS_PORT}
>>>>> 
>>>>> An any C call is like:
>>>>> ssh_options_set(my_ssh_session, SSH_OPTIONS_HOST, "localhost");
>>>>> 
>>>>> GS generated wrapper:
>>>>> ssh_options_set_: session _: type _: value
>>>>>    "Interpreted as #int32 from #( #'ptr' #'ptr' #'ptr' )"
>>>>>    ^Functionssh_options_set callWith: { session. type. value }
>>>>> 
>>>>> In GS i tried something like:
>>>>> myLibrary ssh_options_set_: session _: optionHost _: hostName
>>>>> where
>>>>> session: is created in another successful call to myLibrary
>>>>> 
>>>>> optionHost:
>>>>> cStructPointer := CByteArray gcMalloc: 8.
>>>>> cStructPointer uint64At: 0 put: 0. "0 correspond to SSH_OPTIONS_HOST - maybe i'm wrong"
>>>>> 
>>>>> hostName: CByteArray withAll: 'localhost'
>>>>> 
>>>>> But it seems that something is wrong. The chapter 18 do something like this with another library.
>>>>> So [optionHost] or [hostName] has a wrong value...
>>>>> For now no successful call passing an enum element.
>>>>> 
>>>>> Now back to fight with C :)
>>>>> 
>>>>> regards,
>>>>> bruno
>>>>> 
>>>>> _______________________________________________
>>>>> Glass mailing list
>>>>> Glass at lists.gemtalksystems.com
>>>>> https://lists.gemtalksystems.com/mailman/listinfo/glass
>