So, if the atomic types and structure types are initialized, they make use of ExternalType class >> #pointerSpec to store the size of the pointer in the #headerWord, which is the first element of an external type's 'compiledSpec'. For atomic types, this happens when the FFI package is loaded.
For structure types, this happens when a an external structure is mentioned for the first time in an FFI call method or in during compilation of another external structure's fields. See ExternalType class >> #newTypeNamed:force:. Squeak's Smalltalk parser or the compile logic in ExternalStructure invokes that type creation respectively..
Currently, if a platform change at system startup is detected, all atomic types and structure types are updated --- which implies a call to #pointerSpec in ExternalType class >> #initializeStructureTypes.
Now, what could be the situation where a struct-pointer type had the wrong pointer size? During development, your platform does not magically change the #wordSize. When loading code, methods in the external struct might be wrong (bc. Monticello does not trigger that field re-definition) BUT any external struct-pointer type that is already in the image must have the right size. And for new external struct-pointer types, it should work as explained above.
So, I think we should make the following changes: - Remove ExternalType >> #asPointerType: (! note the colon !) - Remove ExternalType >> #pointerSize: - Change ExternalType >> #pointerSize to just read the compiledSpec - Update all sends to #asPointerType: to #asPointerType and assume that the current pointer-type instances have the right size, as described above.
Best, Marcel
Am 30.05.2020 15:59:31 schrieb Marcel Taeumel marcel.taeumel@hpi.de:
But if it is obsolete now, nuke it.
I cannot tell. That information is stored in the external type's compiledSpec to be used from within the FFI plugin I suppose.
Best, Marcel Am 29.05.2020 00:15:25 schrieb Eliot Miranda eliot.miranda@gmail.com: On Thu, May 28, 2020 at 11:33 AM Nicolas Cellier <> nicolas.cellier.aka.nice@gmail.com> wrote:
Hi Marcel, no idea... Look at timestamp: eem 2/16/2016 12:42 · accessing · 2 implementors · only in change set FFI-Kernel-EstebanLorenzano.45 · So presumably Eliot added that.
Perhaps. I don't remember. But if it is obsolete now, nuke it.
Le jeu. 28 mai 2020 à 17:00, marcel.taeumel a écrit :
Hi Nicolas,
what is the role of ExternalStructure class >> #pointerSize then?
Best, Marcel
Nicolas Cellier wrote
Hi all, beware of FFI 'long' and 'ulong'. They are currently meaning (32 bits) int and unsigned int! This dates back from the 80s when there were still odd OS with segmented memory and 16-bits int. long was thought as a safe int32_t at that time... and still means just that in current FFI.
I'd like to replace them with 'int' and 'uint', but we need to ensure backward compatibility etc...
FFI has ExternalType signedLongLong or just 'longlong' and ExternalType unsignedLongLong or 'ulonglong' which are 64 bits on all architectures. See implementors of #initializeAtomicTypes #initializeFFIConstants
If you want a type that can hold a pointer on both 32 and 64bits arch, then it's doable with a FFI type alias For example I have things like this in HDF5 module Notice the single #(fieldName fieldType) which defines an alias, while ordinary FFI struct gets an array of #(fieldName fieldType) (and replace Size_t with Intptr_t if the purpose is hodling a pointer, otherwise the ayatollahs of C standard will lash you)
ExternalStructure subclass: #'Size_t' instanceVariableNames: '' classVariableNames: '' poolDictionaries: '' category: 'HDF5-External-atomic'
Size_t class >>fields "Size_t defineFields" ^Smalltalk wordSize = 4 ifTrue: [#( value 'ulong')] ifFalse: [#( value 'ulonglong')]
However the "fields" must be re-generated when platform changes... I tried to automate that sometimes ago, see:
ExternalStructure class>>install "Resuming the image on another architecture may require a re-compilation of structure layout." | newPlatform | newPlatform := Smalltalk platformName. PreviousPlatform = newPlatform ifFalse: [self recompileStructures. PreviousPlatform := newPlatform]
It works if you switch from Win64 to MacOS64 for example... However, this mechanism is not used yet at time of code loading, so importing code generated on a different platform won't automatically update the structures (or alias) - the FFI package has no mechanism for that (maybe we could add a hook in MC?).
Le mer. 11 mars 2020 à 23:58, Bert Freudenberg <
bert@
a
écrit :
I'd suggest to get OpenGL working outside of Croquet first:
http://www.squeaksource.com/CroquetGL.html
Step 1: Verify this works in 32 bits. (assuming you are doing this on Linux, you can run 32 bit Squeak side-by-side with the 64 bit one) Step 2: Make it work in 64 bits.
The second step requires that you understand how FFI works, and how it handles e.g. pointers and integer sizes. I am assuming we do have a working 64 bit FFI, at least for x86_64 machines.
E.g. the OGLUnix>>glExtGetProcAddress: method returns a pointer. On a
32
bit system, that fits into a 'ulong' which is 32 bits. On a 64 bit system, a pointer is 64 bits wide so it would not fit into a 32 bit word. Now I don't know how many bits 'ulong' has in our 64 bit FFI, but that declaration may have to change. Etc. pp.
If you have questions about FFI then those are best directed at the vm-dev list since it is dealing with VM-level interfaces. CC'ing, please
follow
up there.
- Bert -
On Wed, Mar 11, 2020 at 2:54 PM gettimothy via Squeak-dev <>
squeak-dev@.squeakfoundation
wrote:
Okey dokey,
Poking along, there is a stray glyph in OGLUnix openGLLibraryName
after
openGLLibraryName ^Smalltalk osVersion = 'linux' ifTrue: ['libGL.so.1'] ifFalse: ['GL']
I removed it in my install and got past that error.
Working exclusively with Croquet(Master)...
My next error is in OGLUnixX11LE(OpenGL)>>glMatrixMode:
glMatrixMode: mode "This method was automatically generated." "void glMatrixMode(GLenum mode);"
^self externalCallFailed
The
fails
How to think about this?
Is Croquet behind OpenGL latest? Would teaching myself OpenGL programming be of use to the Croquet project?
cheers,
tty
-- Sent from: http://forum.world.st/Squeak-VM-f104410.html
-- _,,,^..^,,,_ best, Eliot
On Thu, May 28, 2020 at 11:33 AM Nicolas Cellier <nicolas.cellier.aka.nice@gmail.com [mailto:nicolas.cellier.aka.nice@gmail.com]> wrote:
Hi Marcel, no idea... Look at timestamp: eem 2/16/2016 12:42 · accessing · 2 implementors · only in change set FFI-Kernel-EstebanLorenzano.45 · So presumably Eliot added that.
Perhaps. I don't remember. But if it is obsolete now, nuke it.
Le jeu. 28 mai 2020 à 17:00, marcel.taeumel <Marcel.Taeumel@hpi.de [mailto:Marcel.Taeumel@hpi.de]> a écrit :
Hi Nicolas,
what is the role of ExternalStructure class >> #pointerSize then?
Best,
Marcel
Nicolas Cellier wrote
Hi all,
beware of FFI 'long' and 'ulong'.
They are currently meaning (32 bits) int and unsigned int!
This dates back from the 80s when there were still odd OS with segmented
memory and 16-bits int.
long was thought as a safe int32_t at that time... and still means just
that in current FFI.
I'd like to replace them with 'int' and 'uint', but we need to ensure
backward compatibility etc...
FFI has ExternalType signedLongLong or just 'longlong' and ExternalType
unsignedLongLong or 'ulonglong' which are 64 bits on all architectures.
See implementors of #initializeAtomicTypes #initializeFFIConstants
If you want a type that can hold a pointer on both 32 and 64bits arch,
then
it's doable with a FFI type alias
For example I have things like this in HDF5 module
Notice the single #(fieldName fieldType) which defines an alias, while
ordinary FFI struct gets an array of #(fieldName fieldType)
(and replace Size_t with Intptr_t if the purpose is hodling a pointer,
otherwise the ayatollahs of C standard will lash you)
ExternalStructure subclass: #'Size_t'
instanceVariableNames: ''
classVariableNames: ''
poolDictionaries: ''
category: 'HDF5-External-atomic'
Size_t class >>fields
"Size_t defineFields"
^Smalltalk wordSize = 4
ifTrue: [#( value 'ulong')]
ifFalse: [#( value 'ulonglong')]
However the "fields" must be re-generated when platform changes...
I tried to automate that sometimes ago, see:
ExternalStructure class>>install
"Resuming the image on another architecture may require a
re-compilation of structure layout."
| newPlatform |
newPlatform := Smalltalk platformName.
PreviousPlatform = newPlatform
ifFalse:
[self recompileStructures.
PreviousPlatform := newPlatform]
It works if you switch from Win64 to MacOS64 for example...
However, this mechanism is not used yet at time of code loading, so
importing code generated on a different platform won't automatically
update
the structures (or alias) - the FFI package has no mechanism for that
(maybe we could add a hook in MC?).
Le mer. 11 mars 2020 à 23:58, Bert Freudenberg <
bert@
> a
écrit :
I'd suggest to get OpenGL working outside of Croquet first:
http://www.squeaksource.com/CroquetGL.html [http://www.squeaksource.com/CroquetGL.html]
Step 1: Verify this works in 32 bits. (assuming you are doing this on
Linux, you can run 32 bit Squeak side-by-side with the 64 bit one)
Step 2: Make it work in 64 bits.
The second step requires that you understand how FFI works, and how it
handles e.g. pointers and integer sizes.
I am assuming we do have a working 64 bit FFI, at least for x86_64
machines.
E.g. the OGLUnix>>glExtGetProcAddress: method returns a pointer. On a 32
bit system, that fits into a 'ulong' which is 32 bits. On a 64 bit
system,
a pointer is 64 bits wide so it would not fit into a 32 bit word. Now I
don't know how many bits 'ulong' has in our 64 bit FFI, but that
declaration may have to change. Etc. pp.
If you have questions about FFI then those are best directed at the
vm-dev
list since it is dealing with VM-level interfaces. CC'ing, please follow
up
there.
- Bert -
On Wed, Mar 11, 2020 at 2:54 PM gettimothy via Squeak-dev <
squeak-dev@.squeakfoundation
wrote:
Okey dokey,
Poking along, there is a stray glyph in OGLUnix openGLLibraryName after
openGLLibraryName
^Smalltalk osVersion = 'linux'
ifTrue: ['libGL.so.1']
ifFalse: ['GL']
I removed it in my install and got past that error.
Working exclusively with Croquet(Master)...
My next error is in OGLUnixX11LE(OpenGL)>>glMatrixMode:
glMatrixMode: mode
"This method was automatically generated."
"void glMatrixMode(GLenum mode);"
<apicall: void 'glMatrixMode' (ulong) module: '#openGLLibraryName'>
^self externalCallFailed
The
fails
How to think about this?
Is Croquet behind OpenGL latest?
Would teaching myself OpenGL programming be of use to the Croquet
project?
cheers,
tty
--
Sent from: http://forum.world.st/Squeak-VM-f104410.html [http://forum.world.st/Squeak-VM-f104410.html]
--
_,,,^..^,,,_
best, Eliot