Hey Esteban,
Now that you have outed yourself as a maintainer of FFI, I have a question. :-)
I want to call the libclang function:
/**
* \brief Parse the given source file and the translation unit corresponding
* to that file.
*
* This routine is the main entry point for the Clang C API, providing the
* ability to parse a source file into a translation unit that can then be
* queried by other functions in the API. This routine accepts a set of
* command-line arguments so that the compilation can be configured in the same
* way that the compiler is configured on the command line.
*
* \param CIdx The index object with which the translation unit will be
* associated.
*
* \param source_filename The name of the source file to load, or NULL if the
* source file is included in \c command_line_args.
*
* \param command_line_args The command-line arguments that would be
* passed to the \c clang executable if it were being invoked out-of-process.
* These command-line options will be parsed and will affect how the translation
* unit is parsed. Note that the following options are ignored: '-c',
* '-emit-ast', '-fsyntax-only' (which is the default), and '-o \<output file>'.
*
* \param num_command_line_args The number of command-line arguments in
* \c command_line_args.
*
* \param unsaved_files the files that have not yet been saved to disk
* but may be required for parsing, including the contents of
* those files. The contents and name of these files (as specified by
* CXUnsavedFile) are copied when necessary, so the client only needs to
* guarantee their validity until the call to this function returns.
*
* \param num_unsaved_files the number of unsaved file entries in \p
* unsaved_files.
*
* \param options A bitmask of options that affects how the translation unit
* is managed but not its compilation. This should be a bitwise OR of the
* CXTranslationUnit_XXX flags.
*
* \param[out] out_TU A non-NULL pointer to store the created
* \c CXTranslationUnit, describing the parsed code and containing any
* diagnostics produced by the compiler.
*
* \returns Zero on success, otherwise returns an error code.
*/
enum CXErrorCode
clang_parseTranslationUnit2(CXIndex CIdx,
const char *source_filename,
const char *const *command_line_args,
int num_command_line_args,
struct CXUnsavedFile *unsaved_files,
unsigned num_unsaved_files,
unsigned options,
CXTranslationUnit *out_TU);
The parts I'm not clear on are turning an array or ordered collection of strings into an argv/argc, turning an array of CXUnsavedFile's (FFIExternalStruct) into an array of pointers and count, and getting data back in an output argument as CXTranslationUnit which is an opaque pointer to a C++ object.
Any tips on these mappings would be great. I've currently guessed it as:
clang_parseTranslationUnit__cxIndex: cxIndex source: sourceFile arguments: argv unsavedFiles:unsaved options: opts
| argc unsaved_files num_unsaved_files options error out_TU |
argc := argv size.
unsaved_files := unsaved ifNil: [ #() ] ifNotNil: [ unsaved ].
num_unsaved_files := unsaved_files ifNil: [ 0 ] ifNotNil: [unsaved_files size].
options := opts sum.
error := self ffiCall: #(CXErrorCode clang_parseTranslationUnit2(CXIndex cxIndex,
String sourceFile,
String *argv,
uint argc,
CXUnsavedFile *unsaved_files,
uint num_unsaved_files,
CXTranslationUnitFlag options,
CXTranslationUnit *out_TU)).
(error = CXError_Success) ifTrue: [ ^out_TU ].
self error: error
Thanks.
On Oct 22, 2017, at 2:42 AM, Esteban Lorenzano <estebanlm@gmail.com> wrote:
Hi,
On 21 Oct 2017, at 21:15, Stephane Ducasse <stepharo.self@gmail.com> wrote:
Esteban will probably reply to this thread
yes, I will :)
On Thu, Oct 19, 2017 at 10:34 PM, Todd Blanchard <tblanchard@mac.com> wrote:
I have found the problem with VoidPointer3 generating accessors.
can you report that on fogbugz ?
(along with your solution)
thanks!
Esteban
No idea how to contribute back a fix but this is what I've found.
FFITypeArrayType>>annonymousClassCreator
^ String streamContents: [ :stream |
stream
nextPutAll: '(FFITypeArray ofType: ';
print: (self objectClass type isPointer ifTrue: [self externalTypeWithArity
printString] ifFalse: ['#',self objectClass type class]);
nextPutAll: ' size: ';
print: self objectClass numberOfElements;
nextPutAll: ')' ]
Recalling that we are trying to come up with an accessor that can pull out a
void*[3], this produces
'(FFITypeArray ofType: #FFIVoid size: 3)'
which produces an error as FFIVoid's size is undefined. In general, this
will be wrong for any pointer type and will probably get the size
calculation wrong.
Doing a little digging I find that
FFITypeArray>>ofType: aType size: aSize
delegates resolution of aType to FFIExternalType>>resolveType:aType and this
can take all kinds of different things including the native type name.
It would be better if this generated the native name for pointers.
(FFITypeArray ofType: 'void*' size: 3)
So I changed it to:
FFITypeArrayType>>annonymousClassCreator
^ String streamContents: [ :stream |
stream
nextPutAll: '(FFITypeArray ofType: ';
print: (self objectClass type isPointer
ifTrue: [self externalTypeWithArity printString]
ifFalse: ['#',self objectClass type class]);
nextPutAll: ' size: ';
print: self objectClass numberOfElements;
nextPutAll: ')' ]
and this seems to work fine.
Onwards...
On Oct 19, 2017, at 7:18 AM, Todd Blanchard <tblanchard@mac.com> wrote:
That���s great - it���s been kind of magical but a couple things have changed
since you wrote it and some bugs have crept into ffi.
Right now I���m finding the generated accessor for the VoidPointer3 is
actually generating a void 3 accessor and that doesn���t work. I spent all day
yesterday tracking it to the accessor generating code.
Sent from the road
On Oct 18, 2017, at 22:29, Ben Coman <btc@openinworld.com> wrote:
On Thu, Oct 19, 2017 at 1:05 AM, Todd Blanchard <tblanchard@mac.com> wrote:
I'm working through Ben's great blog post about playing with libclang and
I am puzzled by something.
Thx Todd. Knowing someone is looking at it encourages me to expand it.
I'm interested in looking at your specific questions, but it might not be
until next week after this stint of long work days.
cheers -ben
invalidateSessionData
handle atAllPut: 0.
zero;s out the handle. Cool. However,
handle isNull
does not return true despite it being used in the getString method as
^ handle isNull
ifTrue: ['external memory invalidated by session restart']
ifFalse:[LibClang clang_getCString__cxString: self].
Looks like there should be an isNull on ByteArray that returns true if all
bytes are zero but it isn't there. Was it dropped for some reason?
On Oct 18, 2017, at 2:58 AM, Dimitris Chloupis <kilon.alios@gmail.com>
wrote:
Sure the documentation could be better, that is definetly important, but
is already good enough and UFFI is a very technical subject much more suited
to a mailing list . Its not physical possible to cover the massive potential
of UFFI.
On Wed, Oct 18, 2017 at 9:32 AM Stephane Ducasse <stepharo.self@gmail.com>
wrote:
Please do not hesitate to do Pull Requests.
Luc told me that he wants to do a pass on it and Esteban promises that to
me
but he is super busy.
Stef
On Wed, Oct 18, 2017 at 5:54 AM, Todd Blanchard <tblanchard@mac.com>
wrote:
Wonderful! Thanks.
On Oct 17, 2017, at 3:45 PM, stephan <stephan@stack.nl> wrote:
On 17-10-17 23:06, Todd Blanchard wrote:
Anyone know what happened to this?
https://ci.inria.fr/pharo-contribution/view/Books/job/PharoBookWorkInProgress/lastSuccessfulBuild/artifact/book-result/UnifiedFFI/UnifiedFFI.pdf
https://github.com/SquareBracketAssociates/Booklet-uFFI
has a link to a bintray pdf download
Stephan