readcon-core 0.14.9

An oxidized single and multiple CON file reader and writer with FFI bindings for ergonomic C/C++ usage. Implements CON spec v3.
Documentation 
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pub mod read_con_capnp {
    #![allow(unused_parens)]
    include!(concat!(env!("OUT_DIR"), "/ReadCon_capnp.rs"));
}

pub mod client;
pub mod convert;
pub mod endpoint;
pub mod server;

pub use endpoint::Endpoint;

use read_con_capnp::compatibility_stamp;

/// Fill a wire compatibility record with this library's negotiated contract.
pub fn set_compatibility_stamp(mut stamp: compatibility_stamp::Builder<'_>) {
    stamp.set_abi_major(crate::ffi::RKR_ABI_VERSION_MAJOR);
    stamp.set_abi_minor(crate::ffi::RKR_ABI_VERSION_MINOR);
    stamp.set_abi_layout_revision(crate::ffi::RKR_ABI_LAYOUT_REVISION);
    stamp.set_con_spec_version(crate::CON_SPEC_VERSION);
}

/// Reject a wire compatibility record that this library cannot safely consume.
pub fn validate_compatibility_stamp(stamp: compatibility_stamp::Reader<'_>) -> Result<(), String> {
    if stamp.get_abi_major() != crate::ffi::RKR_ABI_VERSION_MAJOR {
        return Err(format!(
            "incompatible readcon-core ABI major: {}",
            stamp.get_abi_major()
        ));
    }
    if stamp.get_abi_minor() > crate::ffi::RKR_ABI_VERSION_MINOR {
        return Err(format!(
            "unsupported readcon-core ABI minor: {}",
            stamp.get_abi_minor()
        ));
    }
    if stamp.get_abi_layout_revision() != crate::ffi::RKR_ABI_LAYOUT_REVISION {
        return Err(format!(
            "incompatible readcon-core ABI layout: {}",
            stamp.get_abi_layout_revision()
        ));
    }
    if stamp.get_con_spec_version() > crate::CON_SPEC_VERSION {
        return Err(format!(
            "unsupported CON spec version: {}",
            stamp.get_con_spec_version()
        ));
    }
    Ok(())
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn rejects_a_breaking_abi_major() {
        let mut message = capnp::message::Builder::new_default();
        {
            let mut stamp = message.init_root::<compatibility_stamp::Builder>();
            stamp.set_abi_major(2);
            stamp.set_abi_minor(crate::ffi::RKR_ABI_VERSION_MINOR);
            stamp.set_abi_layout_revision(crate::ffi::RKR_ABI_LAYOUT_REVISION);
            stamp.set_con_spec_version(crate::CON_SPEC_VERSION);
        }
        let stamp = message
            .get_root_as_reader::<compatibility_stamp::Reader>()
            .expect("compatibility stamp root");
        let error = validate_compatibility_stamp(stamp).expect_err("major mismatch must fail");
        assert!(error.contains("ABI major"));
    }

    #[test]
    fn rejects_a_newer_abi_minor() {
        let mut message = capnp::message::Builder::new_default();
        {
            let mut stamp = message.init_root::<compatibility_stamp::Builder>();
            stamp.set_abi_major(crate::ffi::RKR_ABI_VERSION_MAJOR);
            stamp.set_abi_minor(crate::ffi::RKR_ABI_VERSION_MINOR + 1);
            stamp.set_abi_layout_revision(crate::ffi::RKR_ABI_LAYOUT_REVISION);
            stamp.set_con_spec_version(crate::CON_SPEC_VERSION);
        }
        let stamp = message
            .get_root_as_reader::<compatibility_stamp::Reader>()
            .expect("compatibility stamp root");
        let error = validate_compatibility_stamp(stamp).expect_err("newer minor must fail");
        assert!(error.contains("ABI minor"));
    }
}