[LAD] RDF libraries, was Re: [ANN] IR: LV2 Convolution Reverb

[Stefano D'Angelo]

2011/2/26 Stefano D'Angelo <zanga.mail at gmail.com>:
> 2011/2/25 David Robillard <d at drobilla.net>:
>> On Fri, 2011-02-25 at 21:09 +0100, Olivier Guilyardi wrote:
>>> On 02/25/2011 08:57 PM, David Robillard wrote:
>>>
>>> >> It's a few months ago now that I investigated LV2. IIRC, at that time I
>>> >> concluded that this wasn't an option because SLV2 was GPL'ed. But things are
>>> >> changing IIUC :)
>>> >
>>> > You never asked. I would have changed it... but I am not psychic ;)
>>>
>>> It's not always easy to discuss about religious matters, such as licenses ;)
>>>
>>> That said there is another big problem. This glib dependency, it's way too heavy
>>> for mobile deployment.
>>
>> Glib was the most effective route of getting the job done - rewriting
>> the few bits that are required is not an effective use of my time right
>> now (it's not exposed in the API, so it's not a compatibility issue, and
>> there's a ton of more pressing LV2 things that need doing).
>>
>> I'm not a huge fan of wheel-reinventing, and on PCs glib is about as
>> unoffensive a dependency as they come. On mobile, I guess that meg or so
>> actually makes a difference.
>>
>> Replacing glib will not be very difficult, very little of it is used:
>> just a balanced BST, dynamic array, and ideally a hash table or trie
>> other appropriate structure for string interning (the BST would do for
>> this part, with a bit of a performance cost). Good old-fashioned data
>> structure implementation is my favourite thing to do, but unfortunately
>> there is no shortage of more pragmatic things that need doing ;)
>>
>> Perhaps Stefano's NASPRO core work will do, or using C++ internally, or
>> just tearing the required bits out of glib itself. Sqlite has an
>> in-memory hash table IIRC. Code abounds.
>>
>> Present a viable alternative, and I'll switch sord/slv2 to it, but I
>> have no good reason to invest time in reinventing glib right now.
>
> Given the discussions we had already, NASPRO core could be a viable alternative.
>
> Pros:
> - no dependencies apart from libc and libm
> - size (181K without stripping on Arch Linux x86-64, -O2)
> - high portability, little and confined platform-specific code,
> compiler-specific (symbol visibility, etc.) code confined to a small
> header
> - gracefully handles platform-specific conventions (i.e., ':' vs ';'
> in path variables, zero-length prefixes in path variables under *nix,
> directory separators, etc.)
> - total amount of code is circa 7.5k lines, including comments and
> public headers
> - UTF-8 support, conversion from/to UTF-16 LE, serious UTF-8 grapheme
> counting is supported
> - thread safety (e.g., data types are synchronized at a very granular
> level, but allow you to have more coarse synchronization if you want)
> - extremely low memory footprint
> - locale-independent asprintf() and vasprintf(), C99 level (except
> "%lc" and "%ls" conversions, possibly they are not even needed if
> using UTF-8)
> - semi-serious, integrated and as-lightweight-as-it-can-be
> error/message reporting mechanism
> - precise and well defined error checking and error codes
> - includes directory traversal, dynamic loading
> - well documented
>
> Cons:
> - not yet released
> - no real test suite and not extensively tested
> - currently implemented data types: doubly linked lists and AVL trees only
> - not yet ported to non POSIX platforms (i.e., Windows)
> - API/ABI are "stable enough", but can't guarantee for total stability
> in the next future (i.e., no big changes will happen, yet something
> might change)
> - no locale-independent sscanf() or similar
> - no UTF16-BE support/conversion
> - till now, a one man effort
>
> That is, it is certainly possible to make it become viable to replace
> SLV2

Oops, I meant, to replace GLib in SLV2.

Stefano