Ruby FFI not finding certain functions?

Question

I'm trying to use Ruby's FFI library to link functions from the bitcoin-core secp256k1 library .

To make the secp256k1_ecdsa_sign function accessible, I built libsecp256k1 using autotools (as directed in README.md ). Then I created a shared object to use in FFI by running g++ -shared secp256k1/src/.libs/libsecp256k1_la-secp256k1.o . Importing this into my Ruby file using FFI let me use the function and everything worked perfectly.

I'm trying to do the exact same with the secp256k1_ecdsa_sign_recoverable function, which is in the same C project, just a different header file. However, I get the error Function 'secp256k1_ecdsa_sign_recoverable' not found in [bin/secp256k1.so] (FFI::NotFoundError) .

I think this is either because I'm not creating the shared object properly (created with the aforementioned g++ command), or because this function is for some reason not a public-facing one in the C project (though I don't know enough about C to know how to figure out if this is the case).

If someone could help me figure out how to use this function it would be greatly appreciated.

Answer 1

It ends up the secp256k1_recovery.h file is only included if you specify that when building the libsecp256k1 library. Specifically, I needed to run ./configure --enable-module-recovery instead of ./configure .