SoC 2011/Generator of libVLC bindings for other languages - Revision history

DarthGandalf: /* More details */

2011-06-25T17:46:33Z

More details

← Older revision		Revision as of 17:46, 25 June 2011
Line 15:		Line 15:
	When both steps will be done, need to solve the following problem: python modules usually are named with small letters, perl modules are usually named with camelcase, etc. Different languages have different rules for naming. Raw access functions of course should be named exactly as in C libvlc API, but it would be nice for classes and their methods to follow naming guidelines of the language.		When both steps will be done, need to solve the following problem: python modules usually are named with small letters, perl modules are usually named with camelcase, etc. Different languages have different rules for naming. Raw access functions of course should be named exactly as in C libvlc API, but it would be nice for classes and their methods to follow naming guidelines of the language.

	I will use %rename of SWIG. So different vlc.i will just have different %rename's, but will use the same C++ wrapper. Of course, list of %rename's should be generated automatically. Full scheme of the process is here~~: http://alexeysokolov~~.co.~~cc/vlc-swig-scheme-2~~.~~png~~		I will use %rename of SWIG. So different vlc.i will just have different %rename's, but will use the same C++ wrapper. Of course, list of %rename's should be generated automatically. Full scheme of the process was here... But it's no more the case, because architecture was changed.

	== Git repo ==		== Git repo ==
	http://git.videolan.org/?p=vlc/vlc-darthgandalf.git		http://git.videolan.org/?p=vlc/vlc-darthgandalf.git
	git://git.videolan.org/vlc/vlc-darthgandalf.git		git://git.videolan.org/vlc/vlc-darthgandalf.git

DarthGandalf: /* More details */

2011-06-08T10:18:29Z

More details

← Older revision		Revision as of 10:18, 8 June 2011
Line 9:		Line 9:
	Simplified scheme of the whole process: First: libvlc ==c++generator==> libvlc-c++. Then: (libvlc, libvlc-c++) ==swig==> bindings to wanted language (vlc.py, vlc.pm, ...).		Simplified scheme of the whole process: First: libvlc ==c++generator==> libvlc-c++. Then: (libvlc, libvlc-c++) ==swig==> bindings to wanted language (vlc.py, vlc.pm, ...).

	C++ wrapper generator probably can be based on existing python bindings generator. So need to understand how does it work, and write a C++ backend.		C++ wrapper generator <strike>probably can be based on existing python bindings generator. So need to understand how does it work, and write a C++ backend.</strike> uses doxygen XML output as parser of libvlc headers.

	Second step is to use SWIG on both libvlc and generated libvlc-c++. Using C libvlc is for ability to access raw VLC API if needed. And C++ wrapper is for having classes with autorefcounting inside target language (for languages which support that). SWIG maps destructors to stuff like "def __del__" in python and "sub DESTROY" in perl, so when python/perl/whatever-lang-which-supports-that object, which represents an object of libvlc-c++, loses last reference, the destructor with libvlc_blah_release() is called.		Second step is to use SWIG on both libvlc and generated libvlc-c++. Using C libvlc is for ability to access raw VLC API if needed. And C++ wrapper is for having classes with autorefcounting inside target language (for languages which support that). SWIG maps destructors to stuff like "def __del__" in python and "sub DESTROY" in perl, so when python/perl/whatever-lang-which-supports-that object, which represents an object of libvlc-c++, loses last reference, the destructor with libvlc_blah_release() is called.

DarthGandalf: Category is auto, so no need

2011-05-28T04:35:42Z

Category is auto, so no need

← Older revision		Revision as of 04:35, 28 May 2011
Line 20:		Line 20:
	http://git.videolan.org/?p=vlc/vlc-darthgandalf.git		http://git.videolan.org/?p=vlc/vlc-darthgandalf.git
	git://git.videolan.org/vlc/vlc-darthgandalf.git		git://git.videolan.org/vlc/vlc-darthgandalf.git

	~~[[Category:SoC 2011 Project]]~~

DarthGandalf: /* More details */ Second way is chosen

2011-05-27T12:31:06Z

More details: Second way is chosen

← Older revision		Revision as of 12:31, 27 May 2011
Line 13:		Line 13:
	Second step is to use SWIG on both libvlc and generated libvlc-c++. Using C libvlc is for ability to access raw VLC API if needed. And C++ wrapper is for having classes with autorefcounting inside target language (for languages which support that). SWIG maps destructors to stuff like "def __del__" in python and "sub DESTROY" in perl, so when python/perl/whatever-lang-which-supports-that object, which represents an object of libvlc-c++, loses last reference, the destructor with libvlc_blah_release() is called.		Second step is to use SWIG on both libvlc and generated libvlc-c++. Using C libvlc is for ability to access raw VLC API if needed. And C++ wrapper is for having classes with autorefcounting inside target language (for languages which support that). SWIG maps destructors to stuff like "def __del__" in python and "sub DESTROY" in perl, so when python/perl/whatever-lang-which-supports-that object, which represents an object of libvlc-c++, loses last reference, the destructor with libvlc_blah_release() is called.

	When both steps will be done, need to solve the following problem: python modules usually are named with small letters, perl modules are usually named with camelcase, etc. Different languages have different rules for naming. Raw access functions of course should be named exactly as in C libvlc API, but it would be nice for classes and their methods to follow naming guidelines of the language. ~~There're 2 more or less simple ways to achieve this:~~		When both steps will be done, need to solve the following problem: python modules usually are named with small letters, perl modules are usually named with camelcase, etc. Different languages have different rules for naming. Raw access functions of course should be named exactly as in C libvlc API, but it would be nice for classes and their methods to follow naming guidelines of the language.

	One way is to generate different C++ wrappers with different method names for different languages. Of course, using the same generator, with a parameter. Something like "./gencxxwrapper --lang=python". Downside of this is having multiple incompatible C++ wrappers. Some changes (like name of the module itself) are needed for SWIG interface file too, so it will be generated too (probably similar to "Makefile.in -> Makefile"). Though if only module name will need to be changed, it can be specified in argument to swig instead. Full scheme of the process is here: http://alexeysokolov.co.cc/vlc-swig-scheme-1.png		I will use %rename of SWIG. So different vlc.i will just have different %rename's, but will use the same C++ wrapper. Of course, list of %rename's should be generated automatically. Full scheme of the process is here: http://alexeysokolov.co.cc/vlc-swig-scheme-2.png

	~~Second way is to~~ use %rename of SWIG. So different vlc.i will just have different %rename's, but will use the same C++ wrapper. Of course, list of %rename's should be generated automatically. Full scheme of the process is here: http://alexeysokolov.co.cc/vlc-swig-scheme-2.png

	== Git repo ==		== Git repo ==

DarthGandalf at 12:29, 27 May 2011

2011-05-27T12:29:55Z

← Older revision		Revision as of 12:29, 27 May 2011
Line 1:		Line 1:
	{{SoCProject\|year=2011\|student=[[User:DarthGandalf\|Alexey Sokolov]]\|mentor=Rémi Duraffort}}		{{SoCProject\|year=2011\|student=[[User:DarthGandalf\|Alexey Sokolov]]\|mentor=Rémi Duraffort}}

			== Abstract ==

			It would be nice to able to use libvlc from other languages. There're autogenerated bindings for python, and it has nice class interface, but it requires to managing reference count (to call release() in the end) manually, which is not very pythony. The plan is to make an autogenerated C++ wrapper around C libvlc. Reference counting will be automatic via constructors/destructors. Produced wrapper will be used as input for SWIG, which can make bindings for many different languages.

			== More details ==

			Simplified scheme of the whole process: First: libvlc ==c++generator==> libvlc-c++. Then: (libvlc, libvlc-c++) ==swig==> bindings to wanted language (vlc.py, vlc.pm, ...).

			C++ wrapper generator probably can be based on existing python bindings generator. So need to understand how does it work, and write a C++ backend.

			Second step is to use SWIG on both libvlc and generated libvlc-c++. Using C libvlc is for ability to access raw VLC API if needed. And C++ wrapper is for having classes with autorefcounting inside target language (for languages which support that). SWIG maps destructors to stuff like "def __del__" in python and "sub DESTROY" in perl, so when python/perl/whatever-lang-which-supports-that object, which represents an object of libvlc-c++, loses last reference, the destructor with libvlc_blah_release() is called.

			When both steps will be done, need to solve the following problem: python modules usually are named with small letters, perl modules are usually named with camelcase, etc. Different languages have different rules for naming. Raw access functions of course should be named exactly as in C libvlc API, but it would be nice for classes and their methods to follow naming guidelines of the language. There're 2 more or less simple ways to achieve this:

			One way is to generate different C++ wrappers with different method names for different languages. Of course, using the same generator, with a parameter. Something like "./gencxxwrapper --lang=python". Downside of this is having multiple incompatible C++ wrappers. Some changes (like name of the module itself) are needed for SWIG interface file too, so it will be generated too (probably similar to "Makefile.in -> Makefile"). Though if only module name will need to be changed, it can be specified in argument to swig instead. Full scheme of the process is here: http://alexeysokolov.co.cc/vlc-swig-scheme-1.png

			Second way is to use %rename of SWIG. So different vlc.i will just have different %rename's, but will use the same C++ wrapper. Of course, list of %rename's should be generated automatically. Full scheme of the process is here: http://alexeysokolov.co.cc/vlc-swig-scheme-2.png

			== Git repo ==
			http://git.videolan.org/?p=vlc/vlc-darthgandalf.git
			git://git.videolan.org/vlc/vlc-darthgandalf.git

	[[Category:SoC 2011 Project]]		[[Category:SoC 2011 Project]]

DarthGandalf: Created page with "{{SoCProject|year=2011|student=Alexey Sokolov|mentor=Rémi Duraffort}} Category:SoC 2011 Project"

2011-05-27T12:24:09Z

Created page with "{{SoCProject|year=2011|student=Alexey Sokolov|mentor=Rémi Duraffort}} Category:SoC 2011 Project"

New page

{{SoCProject|year=2011|student=[[User:DarthGandalf|Alexey Sokolov]]|mentor=Rémi Duraffort}}

[[Category:SoC 2011 Project]]