mmtkvdb

mmtkvdb is a crate for Rust which provides a memory-mapped key-value database. It uses LMDB and links with an existing liblmdb on the system.

Safety

Because of how memory-mapped I/O is being used and also because of certain assumptions of the underlying LMDB API, opening environments and databases requires unsafe Rust (i.e. the programmer must ensure that certain preconditions are met that cannot be enforced by the compiler to avoid undefined behavior). If you aim to program in safe Rust only, this Rust library is not suitable for you.

API Documentation

For documentation on how to use this crate, refer to the example in src/lib.rs.

License

See contained LICENSE file (MIT License).

Changelog

• 2022-08-27: Version 0.8.2
  • Removed wrong (unnecessary) bound T: Storable in implementation of BorrowStorable for Vec<T> (only [T] needs to be Storable)
  • Re-export storable::BorrowStorable in crate-level module (resulting in all items of module storable being available at crate-level)
  • Directly use question mark operator in all examples
  • Minor code style change (use io::Result<_> instead of Result<_, io::Error>)
• 2022-07-22: Version 0.8.1
  • Fix warning by removing #![feature(core_ffi_c)], which is now stable
  • Removed unnecessary Sized supertrait of Storable
  • Some code cleanup (simplified bounds on GATs in Storable tuples)
• 2022-07-12: Version 0.8.0
  • Trait Ord is no longer required for Storable types.
  • Use deref_owned version 0.10.1
  • Improved documentation
  • Bugfixes
    • The constant Storable::TRIVIAL_CMP was set to true for signed byte slices, which led to wrong comparisons of keys or duplicate values.
    • The macro impl_ord_for_storable was broken. The macro is no longer needed and has been removed, thus the bug does not exist anymore.
  • Changed re-exports
    • A new module cow has been added, which re-exports items from crate deref_owned.
    • All relevant items are now re-exported by the crate-level module as well.
  • Code cleanup
    • Internal macros in storable module have been cleaned up.
    • Cleaner implementation for BorrowStorable which allowed removing the private IsType trait and the public StorableWithOwned trait.
    • Consistent use of GenericCow where applicable
  • Added more tests

For older changes, refer to the CHANGELOG.md file.