Crate vcpkg

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A build dependency for Cargo libraries to find libraries in a Vcpkg tree

From a Vcpkg package name this build helper will emit cargo metadata to link it and it’s dependencies (excluding system libraries, which it does not determine).

The simplest possible usage looks like this :-

// build.rs
vcpkg::find_package("libssh2").unwrap();

The cargo metadata that is emitted can be changed like this :-

// build.rs
vcpkg::Config::new()
    .emit_includes(true)
    .find_package("zlib").unwrap();

If the search was successful all appropriate Cargo metadata will be printed to stdout.

§Static vs. dynamic linking

§Linux and Mac

At this time, vcpkg has a single triplet on macOS and Linux, which builds static link versions of libraries. This triplet works well with Rust. It is also possible to select a custom triplet using the VCPKGRS_TRIPLET environment variable.

§Windows

On Windows there are three configurations that are supported for 64-bit builds and another three for 32-bit. The default 64-bit configuration is x64-windows-static-md which is a community supported configuration that is a good match for Rust - dynamically linking to the C runtime, and statically linking to the packages in vcpkg.

Another option is to build a fully static binary using RUSTFLAGS=-Ctarget-feature=+crt-static. This will link to libraries built with vcpkg triplet x64-windows-static.

For dynamic linking, set VCPKGRS_DYNAMIC=1 in the environment. This will link to libraries built with vcpkg triplet x64-windows. If VCPKGRS_DYNAMIC is set, cargo install will generate dynamically linked binaries, in which case you will have to arrange for dlls from your Vcpkg installation to be available in your path.

§Environment variables

A number of environment variables are available to globally configure which libraries are selected.

  • VCPKG_ROOT - Set the directory to look in for a vcpkg installation. If it is not set, vcpkg will use the user-wide installation if one has been set up with vcpkg integrate install, and check the crate source and target to see if a vcpkg tree has been created by cargo-vcpkg.

  • VCPKGRS_TRIPLET - Use this to override vcpkg-rs’ default triplet selection with your own. This is how to select a custom vcpkg triplet.

  • VCPKGRS_NO_FOO - if set, vcpkg-rs will not attempt to find the library named foo.

  • VCPKGRS_DISABLE - if set, vcpkg-rs will not attempt to find any libraries.

  • VCPKGRS_DYNAMIC - if set, vcpkg-rs will link to DLL builds of ports.

§cargo vcpkg

cargo vcpkg can fetch and build a vcpkg installation of required packages from scratch. It merges package requirements specified in the Cargo.toml of crates in the dependency tree.

§vcpkg_cli

There is also a rudimentary companion crate, vcpkg_cli that allows testing of environment and flag combinations.

C:\src> vcpkg_cli probe -l static mysqlclient
Found library mysqlclient
Include paths:
        C:\src\[..]\vcpkg\installed\x64-windows-static\include
Library paths:
        C:\src\[..]\vcpkg\installed\x64-windows-static\lib
Cargo metadata:
        cargo:rustc-link-search=native=C:\src\[..]\vcpkg\installed\x64-windows-static\lib
        cargo:rustc-link-lib=static=mysqlclient

Structs§

  • Config
    Configuration options for finding packages, setting up the tree and emitting metadata to cargo
  • Library
    Details of a package that was found

Enums§

Functions§