* refactor: add SAX-like benc parser
This is the first part of a series of PRs whose end goal is to avoid
the overhead of tr_variant when parsing bencoded data, e.g. when
parsing .torrent files on startup or when parsing announce/scrape
tracker responses.
This PR introduces a SAX-like benc parser, reimplements variant-benc
to use the SAX benc parser (so that we don't have two benc parsers),
and updates the benc + variant tests.
* refactor: use std::string_view to parse benc
* refactor: simplify private parsing API in variant.cc
* chore: remove unneeded includes
* refactor: merge tr_variantFromBenc and tr_variantFromBencFull
This way all the qualifiers (`const`, `volatile`, `mutable`) are grouped
together, e.g. `T const* const x` vs. `const T* const x`. Also helps reading
types right-to-left, e.g. "constant pointer to constant T" vs. "constant
pointer to T which is constant".
There're places where manual intervention is still required as uncrustify
is not ideal (unfortunately), but at least one may rely on it to do the
right thing most of the time (e.g. when sending in a patch).
The style itself is quite different from what we had before but making it
uniform across all the codebase is the key. I also hope that it'll make the
code more readable (YMMV) and less sensitive to further changes.
1. add the option the code to be used under GPLv2 or GPLv3; previously only GPLv2 was allowed
2. add the "proxy option" as described in GPLv3 so we can add future licenses without having to bulk-edit everything again :)
3. remove the awkward "exception for MIT code in Mac client" clause; it was unnecessary and confusing.
Charles Kerr