Merge branch 'cross' into 'next'

cross compile static binaries for x86_64 and aarch64

See merge request famedly/conduit!569

.envrc

@@ -1,3 +1,5 @@
 #!/usr/bin/env bash
 
 use flake
+
+PATH_add bin

.gitlab-ci.yml

@@ -10,6 +10,14 @@ before_script:
   # Enable nix-command and flakes
   - if command -v nix > /dev/null; then echo "experimental-features = nix-command flakes" >> /etc/nix/nix.conf; fi
 
+  # Add our own binary cache
+  - if command -v nix > /dev/null; then echo "extra-substituters = https://nix.computer.surgery/conduit" >> /etc/nix/nix.conf; fi
+  - if command -v nix > /dev/null; then echo "extra-trusted-public-keys = conduit:ZGAf6P6LhNvnoJJ3Me3PRg7tlLSrPxcQ2RiE5LIppjo=" >> /etc/nix/nix.conf; fi
+
+  # Add crane binary cache
+  - if command -v nix > /dev/null; then echo "extra-substituters = https://crane.cachix.org" >> /etc/nix/nix.conf; fi
+  - if command -v nix > /dev/null; then echo "extra-trusted-public-keys = crane.cachix.org-1:8Scfpmn9w+hGdXH/Q9tTLiYAE/2dnJYRJP7kl80GuRk=" >> /etc/nix/nix.conf; fi
+
   # Add nix-community binary cache
   - if command -v nix > /dev/null; then echo "extra-substituters = https://nix-community.cachix.org" >> /etc/nix/nix.conf; fi
   - if command -v nix > /dev/null; then echo "extra-trusted-public-keys = nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs=" >> /etc/nix/nix.conf; fi
@@ -34,20 +42,70 @@ ci:
       - target
       - .gitlab-ci.d
 
-docker:
+static:x86_64-unknown-linux-musl:
   stage: artifacts
   image: nixos/nix:2.19.2
   script:
-    - nix build .#oci-image
+    # Push artifacts and build requirements to binary cache
+    - ./bin/nix-build-and-cache .#static-x86_64-unknown-linux-musl
 
     # Make the output less difficult to find
-    - cp result docker-image.tar.gz
+    - cp result/bin/conduit conduit
   artifacts:
     paths:
-      - docker-image.tar.gz
+      - conduit
 
-debian:
+static:aarch64-unknown-linux-musl:
   stage: artifacts
+  image: nixos/nix:2.19.2
+  script:
+    # Push artifacts and build requirements to binary cache
+    - ./bin/nix-build-and-cache .#static-aarch64-unknown-linux-musl
+
+    # Make the output less difficult to find
+    - cp result/bin/conduit conduit
+  artifacts:
+    paths:
+      - conduit
+
+oci-image:x86_64-unknown-linux-gnu:
+  stage: artifacts
+  image: nixos/nix:2.19.2
+  script:
+    # Push artifacts and build requirements to binary cache
+    #
+    # Since the OCI image package is based on the binary package, this has the
+    # fun side effect of uploading the normal binary too. Conduit users who are
+    # deploying with Nix can leverage this fact by adding our binary cache to
+    # their systems.
+    - ./bin/nix-build-and-cache .#oci-image
+
+    # Make the output less difficult to find
+    - cp result oci-image.tar.gz
+  artifacts:
+    paths:
+      - oci-image.tar.gz
+
+oci-image:aarch64-unknown-linux-musl:
+  stage: artifacts
+  needs:
+    # Wait for the static binary job to finish before starting so we don't have
+    # to build that twice for no reason
+    - static:aarch64-unknown-linux-musl
+  image: nixos/nix:2.19.2
+  script:
+    # Push artifacts and build requirements to binary cache
+    - ./bin/nix-build-and-cache .#oci-image-aarch64-unknown-linux-musl
+
+    # Make the output less difficult to find
+    - cp result oci-image.tar.gz
+  artifacts:
+    paths:
+      - oci-image.tar.gz
+
+debian:x86_64-unknown-linux-gnu:
+  stage: artifacts
+  # See also `rust-toolchain.toml`
   image: rust:1.70.0
   script:
     - apt-get update && apt-get install -y --no-install-recommends libclang-dev
@@ -55,10 +113,10 @@ debian:
     - cargo deb
 
     # Make the output less difficult to find
-    - mv target/debian/*.deb .
+    - mv target/debian/*.deb conduit.deb
   artifacts:
     paths:
-      - "*.deb"
+      - conduit.deb
   cache:
     key: debian
     paths:

Cargo.toml

@@ -9,12 +9,7 @@ readme = "README.md"
 version = "0.7.0-alpha"
 edition = "2021"
 
-# When changing this, make sure to update the hash near the text "THE
+# See also `rust-toolchain.toml`
-# rust-version HASH" in `flake.nix`. If you don't have Nix installed or
-# otherwise don't know how to do this, ping `@charles:computer.surgery` or
-# `@dusk:gaze.systems` in the matrix room.
-#
-# Also make sure to update the docker image tags in `.gitlab-ci.yml`.
 rust-version = "1.70.0"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html

bin/nix-build-and-cache

@@ -0,0 +1,31 @@
+#!/usr/bin/env bash
+
+set -euo pipefail
+
+# The first argument must be the desired installable
+INSTALLABLE="$1"
+
+# Build the installable and forward any other arguments too
+nix build "$@"
+
+if [ ! -z ${ATTIC_TOKEN+x} ]; then
+
+nix run --inputs-from . attic -- login \
+    conduit \
+        https://nix.computer.surgery/conduit \
+        "$ATTIC_TOKEN"
+
+    push_args=(
+        # Attic and its build dependencies
+        "$(nix path-info --inputs-from . attic)"
+        "$(nix path-info --inputs-from . attic --derivation)"
+
+        # The target installable and its build dependencies
+        "$(nix path-info "$INSTALLABLE" --derivation)"
+        "$(nix path-info "$INSTALLABLE")"
+    )
+
+    nix run --inputs-from . attic -- push conduit "${push_args[@]}"
+else
+    echo "\$ATTIC_TOKEN is unset, skipping uploading to the binary cache"
+fi

flake.lock

@@ -1,21 +1,66 @@
 {
   "nodes": {
+    "attic": {
+      "inputs": {
+        "crane": "crane",
+        "flake-compat": "flake-compat",
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs",
+        "nixpkgs-stable": "nixpkgs-stable"
+      },
+      "locked": {
+        "lastModified": 1705617092,
+        "narHash": "sha256-n9PK4O4X4S1JkwpkMuYm1wHZYJzRqif8g3RuVIPD+rY=",
+        "owner": "zhaofengli",
+        "repo": "attic",
+        "rev": "fbe252a5c21febbe920c025560cbd63b20e24f3b",
+        "type": "github"
+      },
+      "original": {
+        "owner": "zhaofengli",
+        "ref": "main",
+        "repo": "attic",
+        "type": "github"
+      }
+    },
     "crane": {
+      "inputs": {
+        "nixpkgs": [
+          "attic",
+          "nixpkgs"
+        ]
+      },
+      "locked": {
+        "lastModified": 1702918879,
+        "narHash": "sha256-tWJqzajIvYcaRWxn+cLUB9L9Pv4dQ3Bfit/YjU5ze3g=",
+        "owner": "ipetkov",
+        "repo": "crane",
+        "rev": "7195c00c272fdd92fc74e7d5a0a2844b9fadb2fb",
+        "type": "github"
+      },
+      "original": {
+        "owner": "ipetkov",
+        "repo": "crane",
+        "type": "github"
+      }
+    },
+    "crane_2": {
       "inputs": {
         "nixpkgs": [
           "nixpkgs"
         ]
       },
       "locked": {
-        "lastModified": 1705597458,
+        "lastModified": 1706070683,
-        "narHash": "sha256-vJ8Ib9ruxbaBxGEcA0d7dHqxpc6Z+SGR2XIxVeSMuLM=",
+        "narHash": "sha256-iQoXIFviH5QbSKDkWyFJKKUtTcSiCvl1tW18ax+pKfI=",
-        "owner": "ipetkov",
+        "owner": "CobaltCause",
         "repo": "crane",
-        "rev": "742170d82cd65c925dcddc5c3d6185699fbbad08",
+        "rev": "8060686afabc5b042e8982200cb2cc3fd22cf416",
         "type": "github"
       },
       "original": {
-        "owner": "ipetkov",
+        "owner": "CobaltCause",
+        "ref": "crimes-for-cross",
         "repo": "crane",
         "type": "github"
       }
@@ -41,7 +86,38 @@
         "type": "github"
       }
     },
+    "flake-compat": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1673956053,
+        "narHash": "sha256-4gtG9iQuiKITOjNQQeQIpoIB6b16fm+504Ch3sNKLd8=",
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "rev": "35bb57c0c8d8b62bbfd284272c928ceb64ddbde9",
+        "type": "github"
+      },
+      "original": {
+        "owner": "edolstra",
+        "repo": "flake-compat",
+        "type": "github"
+      }
+    },
     "flake-utils": {
+      "locked": {
+        "lastModified": 1667395993,
+        "narHash": "sha256-nuEHfE/LcWyuSWnS8t12N1wc105Qtau+/OdUAjtQ0rA=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "5aed5285a952e0b949eb3ba02c12fa4fcfef535f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "flake-utils_2": {
       "inputs": {
         "systems": "systems"
       },
@@ -75,6 +151,38 @@
       }
     },
     "nixpkgs": {
+      "locked": {
+        "lastModified": 1702539185,
+        "narHash": "sha256-KnIRG5NMdLIpEkZTnN5zovNYc0hhXjAgv6pfd5Z4c7U=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "aa9d4729cbc99dabacb50e3994dcefb3ea0f7447",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixpkgs-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs-stable": {
+      "locked": {
+        "lastModified": 1702780907,
+        "narHash": "sha256-blbrBBXjjZt6OKTcYX1jpe9SRof2P9ZYWPzq22tzXAA=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "1e2e384c5b7c50dbf8e9c441a9e58d85f408b01f",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-23.11",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "nixpkgs_2": {
       "locked": {
         "lastModified": 1705496572,
         "narHash": "sha256-rPIe9G5EBLXdBdn9ilGc0nq082lzQd0xGGe092R/5QE=",
@@ -92,11 +200,12 @@
     },
     "root": {
       "inputs": {
-        "crane": "crane",
+        "attic": "attic",
+        "crane": "crane_2",
         "fenix": "fenix",
-        "flake-utils": "flake-utils",
+        "flake-utils": "flake-utils_2",
         "nix-filter": "nix-filter",
-        "nixpkgs": "nixpkgs"
+        "nixpkgs": "nixpkgs_2"
       }
     },
     "rust-analyzer-src": {

flake.nix

@@ -9,9 +9,13 @@
       inputs.nixpkgs.follows = "nixpkgs";
     };
     crane = {
-      url = "github:ipetkov/crane";
+      # TODO: Switch back to upstream after [this issue][0] is fixed
+      #
+      # [0]: https://github.com/ipetkov/crane/issues/497
+      url = "github:CobaltCause/crane?ref=crimes-for-cross";
       inputs.nixpkgs.follows = "nixpkgs";
     };
+    attic.url = "github:zhaofengli/attic?ref=main";
   };
 
   outputs =
@@ -22,59 +26,122 @@
 
     , fenix
     , crane
+    , ...
     }: flake-utils.lib.eachDefaultSystem (system:
     let
-      pkgs = nixpkgs.legacyPackages.${system};
+      pkgsHost = nixpkgs.legacyPackages.${system};
-
-      # Use mold on Linux
-      stdenv = if pkgs.stdenv.isLinux then
-        pkgs.stdenvAdapters.useMoldLinker pkgs.stdenv
-      else
-        pkgs.stdenv;
 
       # Nix-accessible `Cargo.toml`
       cargoToml = builtins.fromTOML (builtins.readFile ./Cargo.toml);
 
       # The Rust toolchain to use
-      toolchain = fenix.packages.${system}.toolchainOf {
+      toolchain = fenix.packages.${system}.fromToolchainFile {
-        # Use the Rust version defined in `Cargo.toml`
+        file = ./rust-toolchain.toml;
-        channel = cargoToml.package.rust-version;
 
-        # THE rust-version HASH
+        # See also `rust-toolchain.toml`
         sha256 = "sha256-gdYqng0y9iHYzYPAdkC/ka3DRny3La/S5G8ASj0Ayyc=";
       };
 
-      mkToolchain = fenix.packages.${system}.combine;
+      builder = pkgs:
+        ((crane.mkLib pkgs).overrideToolchain toolchain).buildPackage;
 
-      buildToolchain = mkToolchain (with toolchain; [
+      nativeBuildInputs = pkgs: [
-        cargo
+        # bindgen needs the build platform's libclang. Apparently due to
-        rustc
+        # "splicing weirdness", pkgs.rustPlatform.bindgenHook on its own doesn't
-      ]);
+        # quite do the right thing here.
+        pkgs.buildPackages.rustPlatform.bindgenHook
+      ];
 
-      devToolchain = mkToolchain (with toolchain; [
+      env = pkgs: {
-        cargo
-        clippy
-        rust-src
-        rustc
-
-        # Always use nightly rustfmt because most of its options are unstable
-        fenix.packages.${system}.latest.rustfmt
-      ]);
-
-      builder =
-        ((crane.mkLib pkgs).overrideToolchain buildToolchain).buildPackage;
-
-      nativeBuildInputs = (with pkgs.rustPlatform; [
-        bindgenHook
-      ]);
-
-      env = {
         ROCKSDB_INCLUDE_DIR = "${pkgs.rocksdb}/include";
         ROCKSDB_LIB_DIR = "${pkgs.rocksdb}/lib";
-      };
+      }
+      // pkgs.lib.optionalAttrs pkgs.stdenv.hostPlatform.isStatic {
+        ROCKSDB_STATIC = "";
+      }
+      // {
+        CARGO_BUILD_RUSTFLAGS = let inherit (pkgs) lib stdenv; in
+          lib.concatStringsSep " " ([]
+            ++ lib.optionals
+              # This disables PIE for static builds, which isn't great in terms
+              # of security. Unfortunately, my hand is forced because nixpkgs'
+              # `libstdc++.a` is built without `-fPIE`, which precludes us from
+              # leaving PIE enabled.
+              stdenv.hostPlatform.isStatic
+              ["-C" "relocation-model=static"]
+            ++ lib.optionals
+              (stdenv.buildPlatform.config != pkgs.stdenv.hostPlatform.config)
+              ["-l" "c"]
+            ++ lib.optionals
+              # This check has to match the one [here][0]. We only need to set
+              # these flags when using a different linker. Don't ask me why,
+              # though, because I don't know. All I know is it breaks otherwise.
+              #
+              # [0]: https://github.com/NixOS/nixpkgs/blob/612f97239e2cc474c13c9dafa0df378058c5ad8d/pkgs/build-support/rust/lib/default.nix#L36-L39
+              (
+                pkgs.stdenv.hostPlatform.isAarch64
+                  && pkgs.stdenv.hostPlatform.isStatic
+                  && !pkgs.stdenv.isDarwin
+                  && !pkgs.stdenv.cc.bintools.isLLVM
+              )
+              [
+                "-l"
+                "stdc++"
+                "-L"
+                "${stdenv.cc.cc.lib}/${stdenv.hostPlatform.config}/lib"
+              ]
+          );
+      }
+
+      # What follows is stolen from [here][0]. Its purpose is to properly
+      # configure compilers and linkers for various stages of the build, and
+      # even covers the case of build scripts that need native code compiled and
+      # run on the build platform (I think).
+      #
+      # [0]: https://github.com/NixOS/nixpkgs/blob/612f97239e2cc474c13c9dafa0df378058c5ad8d/pkgs/build-support/rust/lib/default.nix#L64-L78
+      // (
+        let
+          inherit (pkgs.rust.lib) envVars;
+        in
+        pkgs.lib.optionalAttrs
+          (pkgs.stdenv.targetPlatform.rust.rustcTarget
+            != pkgs.stdenv.hostPlatform.rust.rustcTarget)
+          (
+            let
+              inherit (pkgs.stdenv.targetPlatform.rust) cargoEnvVarTarget;
             in
             {
-      packages.default = builder {
+              "CC_${cargoEnvVarTarget}" = envVars.ccForTarget;
+              "CXX_${cargoEnvVarTarget}" = envVars.cxxForTarget;
+              "CARGO_TARGET_${cargoEnvVarTarget}_LINKER" =
+                envVars.linkerForTarget;
+            }
+          )
+      // (
+        let
+          inherit (pkgs.stdenv.hostPlatform.rust) cargoEnvVarTarget rustcTarget;
+        in
+        {
+          "CC_${cargoEnvVarTarget}" = envVars.ccForHost;
+          "CXX_${cargoEnvVarTarget}" = envVars.cxxForHost;
+          "CARGO_TARGET_${cargoEnvVarTarget}_LINKER" = envVars.linkerForHost;
+          CARGO_BUILD_TARGET = rustcTarget;
+        }
+      )
+      // (
+        let
+          inherit (pkgs.stdenv.buildPlatform.rust) cargoEnvVarTarget;
+        in
+        {
+          "CC_${cargoEnvVarTarget}" = envVars.ccForBuild;
+          "CXX_${cargoEnvVarTarget}" = envVars.cxxForBuild;
+          "CARGO_TARGET_${cargoEnvVarTarget}_LINKER" = envVars.linkerForBuild;
+          HOST_CC = "${pkgs.buildPackages.stdenv.cc}/bin/cc";
+          HOST_CXX = "${pkgs.buildPackages.stdenv.cc}/bin/c++";
+        }
+      ));
+
+      package = pkgs: builder pkgs {
         src = nix-filter {
           root = ./.;
           include = [
@@ -87,24 +154,19 @@
         # This is redundant with CI
         doCheck = false;
 
-        inherit
+        env = env pkgs;
-          env
+        nativeBuildInputs = nativeBuildInputs pkgs;
-          nativeBuildInputs
-          stdenv;
 
         meta.mainProgram = cargoToml.package.name;
       };
 
-      packages.oci-image =
+      mkOciImage = pkgs: package:
-      let
-        package = self.packages.${system}.default;
-      in
         pkgs.dockerTools.buildImage {
           name = package.pname;
           tag = "latest";
           config = {
-          # Use the `tini` init system so that signals (e.g. ctrl+c/SIGINT) are
+            # Use the `tini` init system so that signals (e.g. ctrl+c/SIGINT)
-          # handled as expected
+            # are handled as expected
             Entrypoint = [
               "${pkgs.lib.getExe' pkgs.tini "tini"}"
               "--"
@@ -114,19 +176,57 @@
             ];
           };
         };
+    in
+    {
+      packages = {
+        default = package pkgsHost;
 
-      devShells.default = (pkgs.mkShell.override { inherit stdenv; }) {
+        oci-image = mkOciImage pkgsHost self.packages.${system}.default;
-        env = env // {
+
+        # Build an OCI image from the musl aarch64 build so we don't have to
+        # build for aarch64 twice (to make a gnu version specifically for the
+        # OCI image)
+        oci-image-aarch64-unknown-linux-musl = mkOciImage
+          pkgsHost
+          self.packages.${system}.static-aarch64-unknown-linux-musl;
+
+        # Don't build a musl x86_64 OCI image because that would be pointless.
+        # Just use the gnu one (i.e. `self.packages."x86_64-linux".oci-image`).
+      } // builtins.listToAttrs (
+        builtins.map
+          (crossSystem: {
+            name = "static-${crossSystem}";
+            value = package (import nixpkgs {
+              inherit system;
+              crossSystem = {
+                config = crossSystem;
+              };
+            }).pkgsStatic;
+          })
+          [
+            "x86_64-unknown-linux-musl"
+            "aarch64-unknown-linux-musl"
+          ]
+      );
+
+      devShells.default = pkgsHost.mkShell {
+        env = env pkgsHost // {
           # Rust Analyzer needs to be able to find the path to default crate
           # sources, and it can read this environment variable to do so. The
           # `rust-src` component is required in order for this to work.
-          RUST_SRC_PATH = "${devToolchain}/lib/rustlib/src/rust/library";
+          RUST_SRC_PATH = "${toolchain}/lib/rustlib/src/rust/library";
         };
 
         # Development tools
-        nativeBuildInputs = nativeBuildInputs ++ [
+        nativeBuildInputs = nativeBuildInputs pkgsHost ++ [
-          devToolchain
+          # Always use nightly rustfmt because most of its options are unstable
-        ] ++ (with pkgs; [
+          #
+          # This needs to come before `toolchain` in this list, otherwise
+          # `$PATH` will have stable rustfmt instead.
+          fenix.packages.${system}.latest.rustfmt
+
+          toolchain
+        ] ++ (with pkgsHost; [
           engage
         ]);
       };

rust-toolchain.toml

@@ -0,0 +1,22 @@
+# This is the authoritiative configuration of this project's Rust toolchain.
+#
+# Other files that need upkeep when this changes:
+#
+# * `.gitlab-ci.yml`
+# * `Cargo.toml`
+# * `flake.nix`
+#
+# Search in those files for `rust-toolchain.toml` to find the relevant places.
+# If you're having trouble making the relevant changes, bug a maintainer.
+
+[toolchain]
+channel = "1.70.0"
+components = [
+    # For rust-analyzer
+    "rust-src",
+]
+targets = [
+    "x86_64-unknown-linux-gnu",
+    "x86_64-unknown-linux-musl",
+    "aarch64-unknown-linux-musl",
+]