There is no obvious reason why not to derive `Copy` and `Clone` for
types that use the `impl_newtype_macro`. Derives are less surprising so
deriving makes the code marginally easier to read.
Currently we rely on the inner bytes with types that are passed across
the FFI boundry when implementing comparison functions (e.g. `Ord`,
`PartialEq`), this is incorrect because the bytes are opaque, meaning
the byte layout is not guaranteed across versions of `libsecp26k1`.
Implement stable comparison functionality by doing:
- Implement `core::cmp` traits by first coercing the data into a stable
form e.g., by serializing it.
- Add fast comparison methods to `secp256k1-sys` types that wrap types
from libsecp, add similar methods to types in `secp256k1` that wrap
`secp256k1-sys` types (just call through to inner type).
- In `secp256k1-sys` feature gate the new `core::cmp` impls on
`not(fuzzing)`, when fuzzing just derive the impls instead.
Any additional methods added to `secp256k1-sys` types are private,
justified by the fact the -sys is meant to be just a thin wrapper around
libsecp256k1, we don't want to commit to supporting additional API
functions.
Please note, the solution presented in this patch is already present for
`secp256k1::PublicKey`, this PR removes that code in favour of deriving
traits that then call down to the same logic in `secp256k1-sys`.
Needed to build secp-sys 0.5 and secp-sys 0.6 in the same tree. Fixes#489.
This PR can be reproduced by running
./vendor-libsecp.sh depend/ 0_6_1 a1102b12196ea27f44d6201de4d25926a2ae9640
in the secp256k1-sys directory.
Currently when debug printing the `RecoverableSignature` we do so byte
by byte, this means that the output differs depending on the endianess
of the machine. If instead we serialize the signature in compact form
then the output is the same irrespective of the endianess.
With this applied the following two commands now pass:
```
cargo test test_debug_output --features=recovery
```
cross test --target powerpc-unknown-linux-gnu test_debug_output --features=recovery
```
Fixes: #375
It's super dangerous to use Cargo features for this, since they can be set
accidentally (or maliciously by any crate in a user's entire dep tree). Instead
we can just require users set `RUSTFLAGS` appropriately, which we can easily
do in our fuzzing scripts.
This feature was not useful for Cargo users, since Cargo does not give you
the kind of fine-grained control over C library linkage that you need. So
it was just unnecessarily confusing and would cause the build to break if
you enabled it accidentally, say, with --all-features.
Tobin C. Harding
Andrew Poelstra
Elichai Turkel
junderw
Dr. Maxim Orlovsky
Tibo-lg
Steven Roose