October 2010 - Pharo-dev - lists.pharo.org

Re: [Pharo-project] Pointer types

by Schwab,Wilhelm K

Sig, Thanks for the insights. Your use of the Smalltalk types as parameters should not surprise me (I've been using StructClass* for a long time), but it does a little. Part of what I am trying to sort out is how all of this will look in the things I have going from meta data to calls. You might have just made that easier. The ease with which you drop into assembly language is impressive. Bill ________________________________________ From: pharo-project-bounces(a)lists.gforge.inria.fr [pharo-project-bounces(a)lists.gforge.inria.fr] On Behalf Of Igor Stasenko [siguctua(a)gmail.com] Sent: Thursday, October 07, 2010 7:58 AM To: Pharo-project(a)lists.gforge.inria.fr Subject: Re: [Pharo-project] Pointer types On 7 October 2010 14:24, Igor Stasenko <siguctua(a)gmail.com> wrote: > On 7 October 2010 14:09, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >> Sig, >> >> I have to start watching the clock here, so I will just throw this out for your consideration. Yes a pointer is a pointer, but there are layers of specificity. If a function expects a double*, ideally passing a FloatArray would "take some work," perhaps in the form of wrapping the argument in a "cast"/adpater of some type and passing that to the function. If I describe an argument to the function as void*, then I do not expect much help. In fact, this is a growing source of trouble for me, because my DOUBLEArray leads me to describe parameters as void* when they should/could be double*. The current FFI *appears* to be helping in other situations by complaining when type A does not fit in slot B. >> >> Clearly if the function is mapped as the wrong type in the code I give you, then the seg fault is on me. But it would be nice if when given a correct (double*, long) argument sequence, you could raise an error if those are reversed. Am I missing something? I gotta go =:0 > > You could even specify that a double* argument expects an argument to > be an instance of DoubleArray, which then will be coerced to pointer. > There's many other things possible, but before you start using it, > you'll never know :) > or , as i said before, just write a function specification as following: foo (DoubleArray array, long dummy) then, in DoubleArray class>>asNBExternalType: answer an instance of your own DoubleArrayType which will be responsible for argument type-checking its coercion to double * and pushing to stack. As an example of implementing custom external type, you can take a look at SqS/NBOpenGL repository a package NBOpelGL-Core For example: NBOpenGL>>color3f_red: "in" red green: "in" green blue: "in" blue "This method was automatically generated from OpenGL specs" "See http://squeaksource.com/OpenGLSpecs for details" <primitive: #primitiveNativeCall module: #NativeBoostPlugin> ^ self glApiCall: #( void glColor3f ( GLfloat red , GLfloat green , GLfloat blue ) ) index: 141 attributes: #( #category #'VERSION_1_0_DEPRECATED' #deprecated #'3.1' #version #'1.0' ) GLfloat is defined in NBOpenGLTypes pool as: GLfloat := #NBGLFloat. And NBGLFloat is a external type subclass: NBFloat32 subclass: #NBGLFloat instanceVariableNames: '' classVariableNames: '' poolDictionaries: '' category: 'NBOpenGL-Core' which overrides #pushAsValue: pushAsValue: gen | proxy asm oop EAX | proxy := gen proxy. asm := gen asm. EAX := asm EAX. oop := loader emitLoad: gen. asm mov: oop to: EAX. proxy oop: EAX ifSmallInt: [ asm sar: EAX with: 1; push: EAX; fild: asm ESP ptr32; fstp: asm ESP ptr32 ] ifNotSmallInt: [ proxy pushFloatOopAsFloat32: EAX. ]. So, in contrast to its superclas (NBFloat32), it accepting a smallints as valid argument, not only instances of Float. >> >> Bill >> >> >> >> ________________________________________ >> From: pharo-project-bounces(a)lists.gforge.inria.fr [pharo-project-bounces(a)lists.gforge.inria.fr] On Behalf Of Igor Stasenko [siguctua(a)gmail.com] >> Sent: Thursday, October 07, 2010 6:49 AM >> To: Pharo-project(a)lists.gforge.inria.fr >> Subject: Re: [Pharo-project] Pointer types >> >> On 7 October 2010 13:35, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >>> Sig, >>> >>> Ultimately, I will have to simply try this, but it reminds me of something that I can't place. Have you considered using a dictionary or other type of collection to store the types? A new handler would then be created and finally hooked into the system by sending a message to connect it; opposite on removal. It might turn out to be very much one-to-one so that what I am wondering about does not apply. >>> >> >> Sure, you can use dictionaries in alias lookup implementation: >> >> MyClass>>externalTypeAlias: aTypeName >> ^ myAliasesDict at: aTypeName ifAbsent: [ nil ] >> >>> Anything that can be double* can also be used with void*. How does that work? >>> >> >> Pointer is a pointer. If function expects a pointer argument, you can >> pass any pointer to it. >> Code generator just checks that an argument you passes can be >> converted to C pointer (bytearray, wordarray, external pointer), >> but sure thing it can't check if you passed char* or double* or void*. >> Such kind of type checking belongs to C compiler :) >> >> So, a pointer types in FFI callout declarations is more like a hint, >> what function expects, rather than something ,which >> influence the generated callout code. >> >> >>> Bill >>> >>> >>> >>> >>> >>> ________________________________________ >>> From: pharo-project-bounces(a)lists.gforge.inria.fr [pharo-project-bounces(a)lists.gforge.inria.fr] On Behalf Of Igor Stasenko [siguctua(a)gmail.com] >>> Sent: Thursday, October 07, 2010 12:41 AM >>> To: Pharo-project(a)lists.gforge.inria.fr >>> Subject: Re: [Pharo-project] Pointer types >>> >>> On 7 October 2010 01:27, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >>>> Sig, >>>> >>>> Am I correct in taking this as a description of how to solve it with NB, not Squeak/Pharo FFI? That's ok, just want to know if there is an applicable lesson on FFI to be extracted. >>>> >>>> You say the NB callout generator knows nothing about types. Is that how it should be? The scenario I have in mind is a bogus type and whether that can/should be flagged at compile time vs. runtime. Maybe all it takes is a scan for a suitable handler before or after the method is compiled. I ask because I hit a related snag with FFI runtime errors being reported as coercion errors when in fact I had used errant types in the callout definitions. IIRC, Andreas patched the compiler to report the bogus types. >>>> >>>> >>>> "Or, if you want make double* type to use it as a DoubleArray, then you can add an alias: >>>> >>>> MyClass>>externalTypeAlias: aTypeName >>>> aTypeName = 'double*' ifTrue: [ ^ #DoubleArray ]. >>>> ^ nil >>>> >>>> Then, any method which contains an FFI callout in MyClass, will use that alias." >>>> >>>> What is MyClass in the above? Is it the class holding the callout method, or it elsewhere in the chain? I ask because it could be a sore spot for maintenance/pluggability. I'm wondering how you and I would independently add such instructions. If it goes in the external type subclass, then it is probably fine; if it goes in a class that makes the call, we might stomp on each other. Make sense? My hunch is that you have it handled. >>>> >>> >>> Its in an any class, which using FFI callouts. We can stomp on each >>> other if you define aliases in Object class :) >>> But this won't be a good idea, isnt? >>> NBExternalType subclasses defining coercions between ST oops and >>> concrete C type, they are not for defining aliases. >>> >>>> >>>> Bill >>>> >>>> >>>> ________________________________________ >>>> From: pharo-project-bounces(a)lists.gforge.inria.fr [pharo-project-bounces(a)lists.gforge.inria.fr] On Behalf Of Igor Stasenko [siguctua(a)gmail.com] >>>> Sent: Monday, October 04, 2010 7:36 AM >>>> To: Pharo-project(a)lists.gforge.inria.fr >>>> Subject: Re: [Pharo-project] Pointer types >>>> >>>> On 4 October 2010 06:15, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >>>>> Sig, >>>>> >>>>> You mentioned something that might be useful, depending on where it lives. Our ability to use underscores now leaves me thinking I really should rework some things that suffered mightily: there are some external things that are named assuming underscores, and in mixed case, they turn into an unreadable mess. Along with this, I have a large number of FFI calls that take double pointers, and I have for some time been demoralized into (or stupid enough to<g>) expressing them as void pointers to allow me to pass byte arrays into them. >>>>> >>>>> Is there a way that I can get FFI to recognize DOUBLEArray (which uses a ByteArray to hold its data) as something that should be acceptable for a double* call? If not FFI, how does NB handle it? >>>>> >>>> >>>> In NB, there is a type system, which implements C<->Smalltalk coercions. >>>> The responsibility of type coercions taken by a subclasses of NBExternalType, >>>> so NB callout code generator actually knows nothing about types and >>>> how to coerce them. >>>> >>>> To create own custom type, you need to subclass from NBExternalType >>>> and override methods which responsible for coercions. >>>> There you can define any kind of operations , what needs to be done in >>>> order to push value on stack, or >>>> convert it to some smalltalk object. >>>> >>>> Then, in your DoubleArray class, simply implement a message on a class side: >>>> >>>> asNBExternalType: gen >>>> >>>> ^ MyDoubleArrayExternalType new >>>> >>>> >>>> And then, in FFI callouts you can use a class name directly: >>>> >>>> DoubleArray foo (DoubleArray arr, DoubleArray * arrPtr) >>>> >>>> etc. >>>> >>>> Or, if you want make double* type to use it as a DoubleArray, then you >>>> can add an alias: >>>> >>>> MyClass>>externalTypeAlias: aTypeName >>>> aTypeName = 'double*' ifTrue: [ ^ #DoubleArray ]. >>>> ^ nil >>>> >>>> Then, any method which contains an FFI callout in MyClass, >>>> will use that alias. So, you can write callout as: >>>> >>>> double* foo (double *arr, double ** arrPtrPtr) >>>> >>>> but it will be understood as: >>>> >>>> DoubleArray foo (DoubleArray arr, DoubleArray * arrPtr) >>>> >>>> >>>> About handling pointers.. well for smalltalk there is no pointers, just objects. >>>> So, in NB NBExternalType keeps two things: >>>> - a value type >>>> - a pointer arity >>>> >>>> >>>> So, for example, when you specifying type, like: >>>> char *** >>>> >>>> a value type will be char >>>> and pointer arity will be 3. >>>> >>>> It is up to NBExternalType subclass how to push values whose pointer arity > 0. >>>> By default, if pointerArity > 0, then it is treated as a pointer, >>>> which can be either: - nil, ByteArray, or NBExternalAddress >>>> >>>> >>>>> Bill >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Pharo-project mailing list >>>>> Pharo-project(a)lists.gforge.inria.fr >>>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>>>> >>>> >>>> >>>> >>>> -- >>>> Best regards, >>>> Igor Stasenko AKA sig. >>>> >>>> _______________________________________________ >>>> Pharo-project mailing list >>>> Pharo-project(a)lists.gforge.inria.fr >>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>>> >>>> _______________________________________________ >>>> Pharo-project mailing list >>>> Pharo-project(a)lists.gforge.inria.fr >>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>>> >>> >>> >>> >>> -- >>> Best regards, >>> Igor Stasenko AKA sig. >>> >>> _______________________________________________ >>> Pharo-project mailing list >>> Pharo-project(a)lists.gforge.inria.fr >>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>> >>> _______________________________________________ >>> Pharo-project mailing list >>> Pharo-project(a)lists.gforge.inria.fr >>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>> >> >> >> >> -- >> Best regards, >> Igor Stasenko AKA sig. >> >> _______________________________________________ >> Pharo-project mailing list >> Pharo-project(a)lists.gforge.inria.fr >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >> >> _______________________________________________ >> Pharo-project mailing list >> Pharo-project(a)lists.gforge.inria.fr >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >> > > > > -- > Best regards, > Igor Stasenko AKA sig. > -- Best regards, Igor Stasenko AKA sig. _______________________________________________ Pharo-project mailing list Pharo-project(a)lists.gforge.inria.fr http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project

Oct. 7, 2010

[Pharo-project] XTream was Re: Re: Ocean (was Re: Less plugins, more Smalltalk code!)

by Sven Van Caekenberghe

On 06 Oct 2010, at 08:48, Nicolas Cellier wrote: > See also hijacked http://www.squeaksource.com/XTream.html borrowing > some of the ideas, but somehow less extreme. > Most packages should now load in Pharo. Hi Nicolas, I have been looking at the ESUG 2010 slides & google code project pages of xstreams and I must say that I like this very much. Your code on SS does indeed load in Pharo 1.1. 8 tests fail out of 37 with errors that I think are probably fixable. I am browsing it now. Now my question is, first, do you have some write up somewhere explaining what you did and why, and second, what is the current state of your project and what are your future plans/goals ? Thx, Sven

Oct. 7, 2010

Re: [Pharo-project] WebBrowser

by Mariano Martinez Peck

On Thu, Oct 7, 2010 at 12:56 PM, Torsten Bergmann <astares(a)gmx.de> wrote: > There once was a subclass of AppRegistry called > WebBrowser. This is now gone in "PharoCore 1.2a 12172" > compared to Pharo 1.1 > > Dont know why this specific subclass was removed since > other subclasses of AppRegistry are still in the image > (like MailSender, SoundService, ...) > > Was it by accident or if not what is the idea here. > > However - since this class is missing the package > "ExternalWebBrowser" will fail to load in Pharo 1.2 > since it would like to register itself as a webbrowser in > a class side #initialize. > > Two possibilities: > - we change ExternalWebBrowser > - we reintroduce the missing class (either internal > or in a compatibility package) > > I would change ExternalWebBrowser, add the missing class there, and create a new version in ConfigurationOf that works in 1.2 > Any comments? > > Thx > Torsten > -- > GRATIS! Movie-FLAT mit Ã¼ber 300 Videos. > Jetzt freischalten unter http://portal.gmx.net/de/go/maxdome > > _______________________________________________ > Pharo-project mailing list > Pharo-project(a)lists.gforge.inria.fr > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project

Oct. 7, 2010

Re: [Pharo-project] [Pharo-users] Pharo Talk ESUG 2010

by Alexandre Bergel

>> You will come to Smalltalks 2010 ? > > Yes, Mariano, Luc and me. Cool! Alexandre -- _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: Alexandre Bergel http://www.bergel.eu ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

Oct. 7, 2010

Re: [Pharo-project] Learning by download all the mcz files from a repository

by Alexandre Bergel

Hi! Romain Robbes has been working on exactly this: http://www.squeaksource.com/Ecco.html I also provide a way to profile each version of a given package in the Spy repository. Cheers, Alexandre On 7 Oct 2010, at 03:23, HwaJong Oh wrote: > > I plan to study history of Metacello. > For that I came up with an idea, what if i download all the mcz in the > metacello repository on squeaksource. > Then sort them by commit time stamp. > > installing very first version of Metacello to last version of > Metacello-Help. Every moment of installation, see the difference by clicking > "Changes" button of monticello browser. > > By doing it, i can grasp the idea, the indents of version and understand how > the design has been changed and know the direction of change. > > What do you think of this idea? > > -HwaJong Oh- > -- > View this message in context: http://forum.world.st/Learning-by-download-all-the-mcz-files-from-a-reposit… > Sent from the Pharo Smalltalk mailing list archive at Nabble.com. > > _______________________________________________ > Pharo-project mailing list > Pharo-project(a)lists.gforge.inria.fr > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project -- _,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;: Alexandre Bergel http://www.bergel.eu ^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;._,.;:~^~:;.

Oct. 7, 2010

Re: [Pharo-project] Pharo Talk ESUG 2010

by Philippe Marschall

On 06.10.2010 12:13, Marcus Denker wrote: > Hi, > > Now online: > > Slides Slideshare: http://www.slideshare.net/esug/pharo > Slides Download: http://www.marcusdenker.de/talks/10ESUG/2010PharoESUG.pdf > Video Web: http://esug2010.objectfusion.fr/tuesday.html > (part of all the Tuesday Videos) > Video for Download: > flv: http://www.marcusdenker.de/talks/10ESUG/esug2010_0914_denker.flv > mp4: http://www.marcusdenker.de/talks/10ESUG/esug2010_0914_denker.mp4 Thanks for all the effort. I really appreciate having slides and videos available for download. Cheers Philippe

Oct. 7, 2010

Re: [Pharo-project] UUID and Cog?

by Philippe Marschall

On 06.10.2010 04:35, Levente Uzonyi wrote: > On Tue, 5 Oct 2010, Philippe Marschall wrote: > >> On 05.10.2010 18:23, Levente Uzonyi wrote: >>> On Tue, 5 Oct 2010, Philippe Marschall wrote: >>> >>>> On 05.10.2010 16:41, David T. Lewis wrote: >>>>> If anyone has any specific information as to the root cause of the >>>>> libuuid >>>>> bug, I'd appreciate if you can update the bug report here: >>>>> >>>>> http://bugs.squeak.org/view.php?id=7358 >>>>> >>>>> I had previously tried to summarize as follows: >>>>> >>>>>> The bug exists in some versions of libuuid on some Linux >>>>>> distributions. >>>>>> The workaround is to compile the plugin internal. The latest versions >>>>>> of Unix VM have the plugin compiled internally, although some >>>>>> users may >>>>>> still experience problems if they have a leftover external plugin >>>>>> from >>>>>> a prior installation. >>>>> >>>>> But it's not clear if this is accurate given the recent reports here. >>>>> In particular, if a precompiled Cog VM with the UUID plugin compiled >>>>> internally leads to a crash, then the above is not a sufficient >>>>> workaround (at least not on Cog). >>>>> >>>>> If we are seeing crashes on Cog with an internal UUID plugin, but >>>>> not on the traditional VM with an internal UUID plugin, then I think >>>>> I smell a pthread related issue. >>>> >>>> How can I find out whether the plugin is compiled internally or not? >>> >>> The crash report lists the loaded plugins. If the plugin name ends with >>> (i), then it's internal, if it ends with (e), then it's external. If >>> you're using Eliot's build, then it's external. >> >> Yeah, that's what I'm using, it's external. >> >>> If you just want a working VM and the quality of UUIDs doesn't matter, >>> then you can safely delete the UUIDPlugin from the lib/squeak/3.9-7/ >>> directory. >> >> Uhm, I'm making Monticello commits and good UUIDs would help. >> > > I think the UUIDGenerator in the image produces UUIDs which are good > enough for MC. > >>>> >>>> What I see in the console is the following: >>>> >>>> Segmentation fault >>>> >>>> >>>> >>>> Smalltalk stack dump: >>>> 0xff79f344 M UUID>initialize -1045926312: a(n) UUID >>>> 0xff79f35c M UUID class(Behavior)>new: -1246728604: a(n) UUID class >>>> 0xff79f380 I UUID class>new -1246728604: a(n) UUID class >>>> >>>> ... >>>> >>>> Most recent primitives >>>> ... >>>> withArgs:executeMethod: >>>> basicNew: >>>> primMakeUUID >>>> >>>> Is there a way to provide more information? >>> >>> The stack dump looks the same as what other people have. The version of >>> your linux might be helpful, so others can reproduce the issue if you >>> don't want to debug it yourself. >> >> Gentoo 64bit: 2.6.35-gentoo-r8 >> util-linux (where libuuid afaik comes from): 2.18-r1 > > Do you have a 32-bit version of libuuid installed? If not, it won't work. I believe so. > What does "ldd UUIDPlugin" print? $dd UUIDPlugin linux-gate.so.1 => (0xffffe000) libuuid.so.1 => /lib32/libuuid.so.1 (0xf771f000) libc.so.6 => /lib32/libc.so.6 (0xf75c4000) /lib/ld-linux.so.2 (0xf7762000) Cheers Philippe

Oct. 7, 2010

[Pharo-project] [update 1.2] #12186

by Marcus Denker

12186 ----- Issue 3071: fixing timestamp tests Issue 3068: Non portable SmalltalkImage>>platformName deprecationWarning Issue 3063: removing explain Issue 3039: There should not be any configuration on Core -- Marcus Denker -- http://www.marcusdenker.de INRIA Lille -- Nord Europe. Team RMoD.

Oct. 7, 2010

Re: [Pharo-project] Pointer types

by Igor Stasenko

On 7 October 2010 14:24, Igor Stasenko <siguctua(a)gmail.com> wrote: > On 7 October 2010 14:09, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >> Sig, >> >> I have to start watching the clock here, so I will just throw this out for your consideration. Â Yes a pointer is a pointer, but there are layers of specificity. Â If a function expects a double*, ideally passing a FloatArray would "take some work," perhaps in the form of wrapping the argument in a "cast"/adpater of some type and passing that to the function. Â If I describe an argument to the function as void*, then I do not expect much help. Â In fact, this is a growing source of trouble for me, because my DOUBLEArray leads me to describe parameters as void* when they should/could be double*. Â The current FFI *appears* to be helping in other situations by complaining when type A does not fit in slot B. >> >> Clearly if the function is mapped as the wrong type in the code I give you, then the seg fault is on me. Â But it would be nice if when given a correct (double*, long) argument sequence, you could raise an error if those are reversed. Â Am I missing something? Â I gotta go =:0 > > You could even specify that a double* argument expects an argument to > be an instance of DoubleArray, which then will be coerced to pointer. > There's many other things possible, but before you start using it, > you'll never know :) > or , as i said before, just write a function specification as following: foo (DoubleArray array, long dummy) then, in DoubleArray class>>asNBExternalType: answer an instance of your own DoubleArrayType which will be responsible for argument type-checking its coercion to double * and pushing to stack. As an example of implementing custom external type, you can take a look at SqS/NBOpenGL repository a package NBOpelGL-Core For example: NBOpenGL>>color3f_red: "in" red green: "in" green blue: "in" blue "This method was automatically generated from OpenGL specs" "See http://squeaksource.com/OpenGLSpecs for details" <primitive: #primitiveNativeCall module: #NativeBoostPlugin> ^ self glApiCall: #( void glColor3f ( GLfloat red , GLfloat green , GLfloat blue ) ) index: 141 attributes: #( #category #'VERSION_1_0_DEPRECATED' #deprecated #'3.1' #version #'1.0' ) GLfloat is defined in NBOpenGLTypes pool as: GLfloat := #NBGLFloat. And NBGLFloat is a external type subclass: NBFloat32 subclass: #NBGLFloat instanceVariableNames: '' classVariableNames: '' poolDictionaries: '' category: 'NBOpenGL-Core' which overrides #pushAsValue: pushAsValue: gen | proxy asm oop EAX | proxy := gen proxy. asm := gen asm. EAX := asm EAX. oop := loader emitLoad: gen. asm mov: oop to: EAX. proxy oop: EAX ifSmallInt: [ asm sar: EAX with: 1; push: EAX; fild: asm ESP ptr32; fstp: asm ESP ptr32 ] ifNotSmallInt: [ proxy pushFloatOopAsFloat32: EAX. ]. So, in contrast to its superclas (NBFloat32), it accepting a smallints as valid argument, not only instances of Float. >> >> Bill >> >> >> >> ________________________________________ >> From: pharo-project-bounces(a)lists.gforge.inria.fr [pharo-project-bounces(a)lists.gforge.inria.fr] On Behalf Of Igor Stasenko [siguctua(a)gmail.com] >> Sent: Thursday, October 07, 2010 6:49 AM >> To: Pharo-project(a)lists.gforge.inria.fr >> Subject: Re: [Pharo-project] Pointer types >> >> On 7 October 2010 13:35, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >>> Sig, >>> >>> Ultimately, I will have to simply try this, but it reminds me of something that I can't place. Â Have you considered using a dictionary or other type of collection to store the types? Â A new handler would then be created and finally hooked into the system by sending a message to connect it; opposite on removal. Â It might turn out to be very much one-to-one so that what I am wondering about does not apply. >>> >> >> Sure, you can use dictionaries in alias lookup implementation: >> >> Â MyClass>>externalTypeAlias: aTypeName >> Â Â ^ myAliasesDict at: aTypeName ifAbsent: [ nil ] >> >>> Anything that can be double* can also be used with void*. Â How does that work? >>> >> >> Pointer is a pointer. If function expects a pointer argument, you can >> pass any pointer to it. >> Code generator just checks that an argument you passes can be >> converted to C pointer (bytearray, wordarray, external pointer), >> but sure thing it can't check if you passed char* or double* or void*. >> Such kind of type checking belongs to C compiler :) >> >> So, a pointer types in FFI callout declarations is more like a hint, >> what function expects, rather than something ,which >> influence the generated callout code. >> >> >>> Bill >>> >>> >>> >>> >>> >>> ________________________________________ >>> From: pharo-project-bounces(a)lists.gforge.inria.fr [pharo-project-bounces(a)lists.gforge.inria.fr] On Behalf Of Igor Stasenko [siguctua(a)gmail.com] >>> Sent: Thursday, October 07, 2010 12:41 AM >>> To: Pharo-project(a)lists.gforge.inria.fr >>> Subject: Re: [Pharo-project] Pointer types >>> >>> On 7 October 2010 01:27, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >>>> Sig, >>>> >>>> Am I correct in taking this as a description of how to solve it with NB, not Squeak/Pharo FFI? Â That's ok, just want to know if there is an applicable lesson on FFI to be extracted. >>>> >>>> You say the NB callout generator knows nothing about types. Â Is that how it should be? Â The scenario I have in mind is a bogus type and whether that can/should be flagged at compile time vs. runtime. Â Maybe all it takes is a scan for a suitable handler before or after the method is compiled. Â I ask because I hit a related snag with FFI runtime errors being reported as coercion errors when in fact I had used errant types in the callout definitions. Â IIRC, Andreas patched the compiler to report the bogus types. >>>> >>>> >>>> "Or, if you want make double* type to use it as a DoubleArray, then you can add an alias: >>>> >>>> MyClass>>externalTypeAlias: aTypeName >>>> Â aTypeName = 'double*' ifTrue: [ ^ #DoubleArray ]. >>>> Â ^ nil >>>> >>>> Then, any method which contains an FFI callout in MyClass, will use that alias." >>>> >>>> What is MyClass in the above? Â Is it the class holding the callout method, or it elsewhere in the chain? Â I ask because it could be a sore spot for maintenance/pluggability. Â I'm wondering how you and I would independently add such instructions. Â If it goes in the external type subclass, then it is probably fine; if it goes in a class that makes the call, we might stomp on each other. Â Make sense? Â My hunch is that you have it handled. >>>> >>> >>> Its in an any class, which using FFI callouts. We can stomp on each >>> other if you define aliases in Object class :) >>> But this won't be a good idea, isnt? >>> NBExternalType subclasses defining coercions between ST oops and >>> concrete C type, they are not for defining aliases. >>> >>>> >>>> Bill >>>> >>>> >>>> ________________________________________ >>>> From: pharo-project-bounces(a)lists.gforge.inria.fr [pharo-project-bounces(a)lists.gforge.inria.fr] On Behalf Of Igor Stasenko [siguctua(a)gmail.com] >>>> Sent: Monday, October 04, 2010 7:36 AM >>>> To: Pharo-project(a)lists.gforge.inria.fr >>>> Subject: Re: [Pharo-project] Pointer types >>>> >>>> On 4 October 2010 06:15, Schwab,Wilhelm K <bschwab(a)anest.ufl.edu> wrote: >>>>> Sig, >>>>> >>>>> You mentioned something that might be useful, depending on where it lives. Â Our ability to use underscores now leaves me thinking I really should rework some things that suffered mightily: there are some external things that are named assuming underscores, and in mixed case, they turn into an unreadable mess. Â Along with this, I have a large number of FFI calls that take double pointers, and I have for some time been demoralized into (or stupid enough to<g>) expressing them as void pointers to allow me to pass byte arrays into them. >>>>> >>>>> Is there a way that I can get FFI to recognize DOUBLEArray (which uses a ByteArray to hold its data) as something that should be acceptable for a double* call? Â If not FFI, how does NB handle it? >>>>> >>>> >>>> In NB, there is a type system, which implements C<->Smalltalk coercions. >>>> The responsibility of type coercions taken by a subclasses of NBExternalType, >>>> so NB callout code generator actually knows nothing about types and >>>> how to coerce them. >>>> >>>> To create own custom type, you need to subclass from NBExternalType >>>> and override methods which responsible for coercions. >>>> There you can define any kind of operations , what needs to be done in >>>> order to push value on stack, or >>>> convert it to some smalltalk object. >>>> >>>> Then, in your DoubleArray class, simply implement a message on a class side: >>>> >>>> asNBExternalType: gen >>>> >>>> Â Â Â Â ^ MyDoubleArrayExternalType new >>>> >>>> >>>> And then, in FFI callouts you can use a class name directly: >>>> >>>> DoubleArray foo (DoubleArray arr, DoubleArray * arrPtr) >>>> >>>> etc. >>>> >>>> Or, if you want make double* type to use it as a DoubleArray, then you >>>> can add an alias: >>>> >>>> MyClass>>externalTypeAlias: aTypeName >>>> Â aTypeName = 'double*' ifTrue: [ ^ #DoubleArray ]. >>>> Â ^ nil >>>> >>>> Then, any method which contains an FFI callout in MyClass, >>>> will use that alias. So, you can write callout as: >>>> >>>> double* foo (double *arr, double ** arrPtrPtr) >>>> >>>> but it will be understood as: >>>> >>>> DoubleArray foo (DoubleArray arr, DoubleArray * arrPtr) >>>> >>>> >>>> About handling pointers.. well for smalltalk there is no pointers, just objects. >>>> So, in NB NBExternalType keeps two things: >>>> Â - a value type >>>> Â - a pointer arity >>>> >>>> >>>> So, for example, when you specifying type, like: >>>> char *** >>>> >>>> a value type will be char >>>> and pointer arity will be 3. >>>> >>>> It is up to NBExternalType subclass how to push values whose pointer arity > 0. >>>> By default, if pointerArity > 0, then it is treated as a pointer, >>>> which can be either: - nil, ByteArray, or NBExternalAddress >>>> >>>> >>>>> Bill >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> Pharo-project mailing list >>>>> Pharo-project(a)lists.gforge.inria.fr >>>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>>>> >>>> >>>> >>>> >>>> -- >>>> Best regards, >>>> Igor Stasenko AKA sig. >>>> >>>> _______________________________________________ >>>> Pharo-project mailing list >>>> Pharo-project(a)lists.gforge.inria.fr >>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>>> >>>> _______________________________________________ >>>> Pharo-project mailing list >>>> Pharo-project(a)lists.gforge.inria.fr >>>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>>> >>> >>> >>> >>> -- >>> Best regards, >>> Igor Stasenko AKA sig. >>> >>> _______________________________________________ >>> Pharo-project mailing list >>> Pharo-project(a)lists.gforge.inria.fr >>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>> >>> _______________________________________________ >>> Pharo-project mailing list >>> Pharo-project(a)lists.gforge.inria.fr >>> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >>> >> >> >> >> -- >> Best regards, >> Igor Stasenko AKA sig. >> >> _______________________________________________ >> Pharo-project mailing list >> Pharo-project(a)lists.gforge.inria.fr >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >> >> _______________________________________________ >> Pharo-project mailing list >> Pharo-project(a)lists.gforge.inria.fr >> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project >> > > > > -- > Best regards, > Igor Stasenko AKA sig. > -- Best regards, Igor Stasenko AKA sig.

Oct. 7, 2010

Re: [Pharo-project] Learning by download all the mcz files from a repository

by Igor Stasenko

On 7 October 2010 10:23, HwaJong Oh <daliot.oh(a)gmail.com> wrote: > > I plan to study history of Metacello. > For that I came up with an idea, what if i download all the mcz in the > metacello repository on squeaksource. > Then sort them by commit time stamp. > > installing very first version of Metacello to last version of > Metacello-Help. Every moment of installation, see the difference by clicking > "Changes" button of monticello browser. > > By doing it, i can grasp the idea, the indents of version and understand how > the design has been changed and know the direction of change. > > What do you think of this idea? Isn't it would be faster to read design document(s), or other documentation? :) Unless you wanna study, how it does the things under the hood, why spending so much effort on it? > > -HwaJong Oh- > -- > View this message in context: http://forum.world.st/Learning-by-download-all-the-mcz-files-from-a-reposit… > Sent from the Pharo Smalltalk mailing list archive at Nabble.com. > > _______________________________________________ > Pharo-project mailing list > Pharo-project(a)lists.gforge.inria.fr > http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project > -- Best regards, Igor Stasenko AKA sig.

Oct. 7, 2010