add371d263 Remove `core2` dependency entirely (Matt Corallo)
b7dd16da99 [IO] Use our own io::Error type (Matt Corallo)
c95b59327a Explicitly use `std::io::Error` when implementing `std` traits (Matt Corallo)
9e1cd372cb Use `io::Error::get_ref()` over `std::error::Error::source()` (Matt Corallo)
3caaadf9bb [IO] Replace the `io::Cursor` re-export with our own `Cursor` (Matt Corallo)
141343edb4 [IO] Move to custom `Read` trait mirroring `std::io::Read` (Matt Corallo)
7395093f94 Stop relying on `Take`'s `by_ref` method (Matt Corallo)
2364e1a877 Stop relying on blanket Read impl for all &mut Read (Matt Corallo)
6aa7ccf841 [IO] Replace `std::io::Sink` usage with our own trivial impl (Matt Corallo)
7eb5d65bda [IO] Provide a macro which implements `io::Write` for types (Matt Corallo)
ac678bb435 [IO] Move to custom `Write` trait mirroring `std::io::Write` (Matt Corallo)
5f2395ce56 Add missing `?Sized` bounds to `io::Write` parameters (Matt Corallo)
2348449d2a Stop relying on `std::io::Write`'s `&mut Write` blanket impl (Matt Corallo)
5e0209569c Use `io::sink` rather than our custom `EmptyWrite` utility (Matt Corallo)
a0ade883b6 [IO] Move io module into selected re-exports (Matt Corallo)
27c7c4e26a Add a `bitcoin_io` crate (Matt Corallo)
Pull request description:
In order to support standard (de)serialization of structs, the
`rust-bitcoin` ecosystem uses the standard `std::io::{Read,Write}`
traits. This works great for environments with `std`, however sadly
the `std::io` module has not yet been added to the `core` crate.
Thus, in `no-std`, the `rust-bitcoin` ecosystem has historically
used the `core2` crate to provide copies of the `std::io` module
without any major dependencies. Sadly, its one dependency,
`memchr`, recently broke our MSRV.
Worse, because we didn't want to take on any excess dependencies
for `std` builds, `rust-bitcoin` has had to have
mutually-exclusive `std` and `no-std` builds. This breaks general
assumptions about how features work in Rust, causing substantial
pain for applications far downstream of `rust-bitcoin` crates.
This is mostly done, I'm still finalizing the `io::Error` commit at the end to drop the `core2` required dep in no-std, but its getting there. Would love further feedback on the approach or code-level review on these first handful of commits.
ACKs for top commit:
tcharding:
ACK add371d263
apoelstra:
ACK add371d263
Kixunil:
ACK add371d263
Tree-SHA512: 18698ea8b1b65108ee0f695d5062d2562c8df2f50bf85d93442648da3b35a4184a5d5d2a493aed0adaadc83f663f0cd2ac735c34941cc9a6fa58d826e548e091
675da34127