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UFFI can not generate Structure accessor of type char[100]

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kilon.alios

UFFI can not generate Structure accessor of type char[100]

I have FFIExternalStructure which has at class side

fieldsDesc

^#(

char data[100];

int count;

)

if I try to do

EphCPPTestStructure rebuildFieldAccessors .

in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "

Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

EstebanLM

Re: UFFI can not generate Structure accessor of type char[100]

it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

kilon.alios

Re: UFFI can not generate Structure accessor of type char[100]

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:

it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

EstebanLM

Re: UFFI can not generate Structure accessor of type char[100]

On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

kilon.alios

Re: UFFI can not generate Structure accessor of type char[100]

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:

On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

EstebanLM

Re: UFFI can not generate Structure accessor of type char[100]

On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)

(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

kilon.alios

Re: UFFI can not generate Structure accessor of type char[100]

then great work^2

Do you want me to add this information to the UFFI documentation ? Probably I will also add some more examples for handles, pointers etc.

I assume this is the repo for the docs of UFFI

https://github.com/SquareBracketAssociates/PharoInProgress

correct ?

On Tue, Nov 8, 2016 at 2:12 PM Esteban Lorenzano <[hidden email]> wrote:

On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)
(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

EstebanLM

Re: UFFI can not generate Structure accessor of type char[100]

yes please :)

On 8 Nov 2016, at 13:32, Dimitris Chloupis <[hidden email]> wrote:

then great work^2

Do you want me to add this information to the UFFI documentation ? Probably I will also add some more examples for handles, pointers etc.

I assume this is the repo for the docs of UFFI

https://github.com/SquareBracketAssociates/PharoInProgress

correct ?

On Tue, Nov 8, 2016 at 2:12 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)
(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

kilon.alios

Re: UFFI can not generate Structure accessor of type char[100]

by the way your code is wrong there is no FFITypeArray ofType: so it looks I will have to go straight to

FFITypeArray ofType:'char' size:100

of course for my case what you mention as

FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

is the one that does exactly what I want.

On Tue, Nov 8, 2016 at 2:38 PM Esteban Lorenzano <[hidden email]> wrote:

yes please :)

On 8 Nov 2016, at 13:32, Dimitris Chloupis <[hidden email]> wrote:

then great work^2

Do you want me to add this information to the UFFI documentation ? Probably I will also add some more examples for handles, pointers etc.

I assume this is the repo for the docs of UFFI

https://github.com/SquareBracketAssociates/PharoInProgress

correct ?

On Tue, Nov 8, 2016 at 2:12 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)
(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

EstebanLM

Re: UFFI can not generate Structure accessor of type char[100]

ah yes… I wrote it by heart :P

you need to declare the array type size, otherwise there is no point on it :)

Char100 := FFITypeArray ofType: aTypeName size: elements.

… and the rest is still the same (you replace FFITypeArray class>>ofType:size: occurrences with Char100)

Esteban

On 8 Nov 2016, at 14:29, Dimitris Chloupis <[hidden email]> wrote:

by the way your code is wrong there is no FFITypeArray ofType: so it looks I will have to go straight to

FFITypeArray ofType:'char' size:100

of course for my case what you mention as

FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

is the one that does exactly what I want.

On Tue, Nov 8, 2016 at 2:38 PM Esteban Lorenzano <[hidden email]> wrote:
yes please :)

On 8 Nov 2016, at 13:32, Dimitris Chloupis <[hidden email]> wrote:

then great work^2

Do you want me to add this information to the UFFI documentation ? Probably I will also add some more examples for handles, pointers etc.

I assume this is the repo for the docs of UFFI

https://github.com/SquareBracketAssociates/PharoInProgress

correct ?

On Tue, Nov 8, 2016 at 2:12 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)
(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

Igor Stasenko

Re: UFFI can not generate Structure accessor of type char[100]

In reply to this post by EstebanLM

On 8 November 2016 at 13:11, Esteban Lorenzano <[hidden email]> wrote:

On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)
(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Your credit is too generous :)
Btw, is this expression:

FFITypeArray ofType: #char.

creates anonymous class, or you making an instance of something?

Because if it anonymous class, i was always warned against use it in such form, and instead use some kind of class initializers to
generate all the 'types' you will use in future i.e.

MyCalss class>>initialize
MyCharr100Type := FFITypeArray ofType: #char size:100.

and then just use it wherever you need i.e.:

mychars := MyChar100Type new.

.. whatever.

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

Best regards,
Igor Stasenko.

kilon.alios

Re: UFFI can not generate Structure accessor of type char[100]

As a said that expression does not exist

The one with size it does exist and creates an instance as you would expect.

No idea what an anonymous class is.

I have experienced some slow downs because creating FFI types seems that copies the data and Pharo chokes with my 3000 bytes char array. So I decided not to use FFI types and instead fetch the data directly from shared memory via the pointer which means

anExternalData getHandle unsignedCharAt: for reading
anExternalData getHandle unsignedCharAt: put: for writing

Plus copying the data to Pharo memory kinda defeats the purpose of using shared memory in the first place and it's unnecessary .

But then I am a special case ... the recommended way remains using those types.

On Wed, 9 Nov 2016 at 03:34, Igor Stasenko <[hidden email]> wrote:

On 8 November 2016 at 13:11, Esteban Lorenzano <[hidden email]> wrote:

On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)
(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Your credit is too generous :)
Btw, is this expression:

FFITypeArray ofType: #char.

creates anonymous class, or you making an instance of something?

Because if it anonymous class, i was always warned against use it in such form, and instead use some kind of class initializers to
generate all the 'types' you will use in future i.e.

MyCalss class>>initialize
MyCharr100Type := FFITypeArray ofType: #char size:100.

and then just use it wherever you need i.e.:

mychars := MyChar100Type new.

.. whatever.

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
Char100 := FFITypeArray ofType: #char.

fieldsDesc
^ #(
Char100 data;
int count;
)

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
"This method was automatically generated"
^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
"This method was automatically generated"
^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

--
Best regards,
Igor Stasenko.

EstebanLM

Re: UFFI can not generate Structure accessor of type char[100]

In reply to this post by Igor Stasenko

On 9 Nov 2016, at 02:33, Igor Stasenko <[hidden email]> wrote:

On 8 November 2016 at 13:11, Esteban Lorenzano <[hidden email]> wrote:

On 8 Nov 2016, at 12:55, Dimitris Chloupis <[hidden email]> wrote:

Thank you Esteban

By the way I really love the design of UFFI , very clean and quite easy to understand , great work to you and Igor :)

UFFI is just mine ;)
(but I sanded in giant shoulders as I took Igor work as inspiration… and to “borrow” many cool ideas)

Your credit is too generous :)
Btw, is this expression:

FFITypeArray ofType: #char.

creates anonymous class, or you making an instance of something?

Because if it anonymous class, i was always warned against use it in such form, and instead use some kind of class initializers to
generate all the 'types' you will use in future i.e.

MyCalss class>>initialize
MyCharr100Type := FFITypeArray ofType: #char size:100.

and then just use it wherever you need i.e.:

mychars := MyChar100Type new.

is exactly like you say :)

Esteban

.. whatever.

Esteban

On Tue, Nov 8, 2016 at 1:54 PM Esteban Lorenzano <[hidden email]> wrote:
On 8 Nov 2016, at 12:49, Dimitris Chloupis <[hidden email]> wrote:

I was reaching a similar conclusion

Currently I have a void pointer to the struct with the members I mentioned

I can get char[100]

pointerToStruct fromCString

and I can get the int with

pointerToStruct getHandle integerAt: 101 size:4 signed: false

so if I want to pass the address of the pointer to my YourStruct instance will I have to initialize with

YourStruct fromHandler: (pointerToStruct getHandle)

is this a correct and safe way to pass the address ?

yes.

Esteban

On Tue, Nov 8, 2016 at 1:21 PM Esteban Lorenzano <[hidden email]> wrote:
it never could.
you need to do a “special type”, who has to be something like:

YourStruct class>>initialize
  Char100 := FFITypeArray ofType: #char.

fieldsDesc
  ^ #(
  Char100 data;
  int count;
  )

but then… you want to optimise that and in field accessors, who will look something like this:

YourStruct >>data
  "This method was automatically generated"
  ^(FFITypeArray ofType: #char size: 100) fromHandle: (handle copyFrom: 1 to: 100)

you can change that for:

YourStruct >>data
  "This method was automatically generated"
  ^Char100 fromHandle: (handle copyFrom: 1 to: 100)

and same for setter.
(other way will work, but it will be suboptimal)

Esteban

> On 8 Nov 2016, at 12:10, Dimitris Chloupis <[hidden email]> wrote:
>
> I have FFIExternalStructure which has at class side
>
> fieldsDesc
> ^#(
> char data[100];
> int count;
> )
>
> if I try to do
>
> EphCPPTestStructure rebuildFieldAccessors .
>
> in order to generate the accessors for the members of the struct it complains with an error that it does not recognise the type of " [ "
>
> Does that mean that char arrays are other arrays are not supported as struct members or will I have to do this manually ?

--
Best regards,
Igor Stasenko.