depot/third_party/tvl/nix/buildGo/default.nix

238 lines
9 KiB
Nix

# Copyright 2019 Google LLC.
# SPDX-License-Identifier: Apache-2.0
#
# buildGo provides Nix functions to build Go packages in the style of Bazel's
# rules_go.
{ pkgs ? import <nixpkgs> { }
, gopkgs
, ...
}:
let
inherit (builtins)
attrNames
baseNameOf
dirOf
elemAt
filter
listToAttrs
map
match
readDir
replaceStrings
toString;
inherit (pkgs) lib runCommand runCommandCC fetchFromGitHub protobuf symlinkJoin go;
goStdlib = buildStdlib go;
# Helpers for low-level Go compiler invocations
spaceOut = lib.concatStringsSep " ";
includeDepSrc = dep: "-I ${dep}";
includeSources = deps: spaceOut (map includeDepSrc deps);
includeDepLib = dep: "-L ${dep}";
includeLibs = deps: spaceOut (map includeDepLib deps);
srcBasename = src: elemAt (match "([a-z0-9]{32}\-)?(.*\.go)" (baseNameOf src)) 1;
srcDest = path: src: "$out/${path}/${srcBasename src}";
srcCopy = path: src: "cp ${src} ${srcDest path src}";
srcList = path: srcs: lib.concatStringsSep "\n" (map (srcCopy path) srcs);
allDeps = deps: lib.unique (lib.flatten (deps ++ (map (d: d.goDeps) deps)));
anyCgo = allDeps: lib.any (d: d.cgo) allDeps;
allLDFLAGS = allDeps: lib.unique (lib.flatten (map (d: d.cgoLDFLAGS) allDeps));
allCgoBuildInputs = allDeps: lib.unique (lib.flatten (map (d: d.cgoBuildInputs) allDeps));
xFlags = x_defs: spaceOut (map (k: "-X ${k}=${x_defs."${k}"}") (attrNames x_defs));
pathToName = p: replaceStrings [ "/" ] [ "_" ] (toString p);
# Add an `overrideGo` attribute to a function result that works
# similar to `overrideAttrs`, but is used specifically for the
# arguments passed to Go builders.
makeOverridable = f: orig: (f orig) // {
overrideGo = new: makeOverridable f (orig // (new orig));
};
buildStdlib = go: runCommandCC "go-stdlib-${go.version}" {
nativeBuildInputs = [ go ];
} ''
HOME=$NIX_BUILD_TOP/home
mkdir $HOME
goroot="$(go env GOROOT)"
cp -R "$goroot/src" "$goroot/pkg" .
chmod -R +w .
GODEBUG=installgoroot=all GOROOT=$NIX_BUILD_TOP go install -v --trimpath std
mkdir $out
cp -r pkg/*_*/* $out
find $out -name '*.a' | while read -r ARCHIVE_FULL; do
ARCHIVE="''${ARCHIVE_FULL#"$out/"}"
PACKAGE="''${ARCHIVE%.a}"
echo "packagefile $PACKAGE=$ARCHIVE_FULL"
done > $out/importcfg
'';
importcfgCmd = { name, deps, out ? "importcfg" }: ''
echo "# nix buildGo ${name}" > "${out}"
cat "${goStdlib}/importcfg" >> "${out}"
${lib.concatStringsSep "\n" (map (dep: ''
find "${dep}" -name '*.a' | while read -r pkgp; do
relpath="''${pkgp#"${dep}/"}"
pkgname="''${relpath%.a}"
echo "packagefile $pkgname=$pkgp"
done >> "${out}"
'') deps)}
'';
# High-level build functions
# Build a Go program out of the specified files and dependencies.
program = { name, srcs, deps ? [ ], x_defs ? { } }:
let
uniqueDeps = allDeps (map (d: d.gopkg) deps);
cgo = anyCgo uniqueDeps;
cgoLDFLAGS = allLDFLAGS uniqueDeps;
cgoBuildInputs = allCgoBuildInputs uniqueDeps;
runCommand = if cgo then runCommandCC else pkgs.runCommand;
in runCommand name {
buildInputs = cgoBuildInputs;
} ''
${importcfgCmd { inherit name; deps = uniqueDeps; }}
${go}/bin/go tool compile -o ${name}.a -importcfg=importcfg -trimpath=$PWD -trimpath=${go} -p main ${includeSources uniqueDeps} ${spaceOut srcs}
mkdir -p $out/bin
export GOROOT_FINAL=go
${go}/bin/go tool link -o $out/bin/${name} -importcfg=importcfg -buildid nix \
-extldflags '${toString cgoLDFLAGS}' \
${xFlags x_defs} ${includeLibs uniqueDeps} ${name}.a
'';
# Build a Go library assembled out of the specified files.
#
# This outputs both the sources and compiled binary, as both are
# needed when downstream packages depend on it.
package = { name, srcs, deps ? [ ], path ? name, packageName ? builtins.baseNameOf path, sfiles ? [ ], cgofiles ? [ ], cfiles ? [ ], cxxfiles ? [ ], cgodeps ? [ ], cgocflags ? [ ], cgoldflags ? [ ] }:
let
uniqueDeps = allDeps (map (d: d.gopkg) deps);
ifCgo = do: lib.optionalString (cgofiles != [ ]) do;
cgoBuild = ifCgo ''
BUILDGO_CFLAGS="${spaceOut (lib.unique (map (d: "-I ${builtins.dirOf d}") cgofiles))} ${lib.concatStringsSep " " cgocflags}"
BUILDGO_LDFLAGS="${spaceOut cgoldflags}"
${go}/bin/go tool cgo -trimpath=$PWD -trimpath=${go} -trimpath=$out/${path} -importpath=${path} -- $BUILDGO_CFLAGS ${spaceOut cgofiles}
for f in $PWD/_obj/*.cgo2.c $PWD/_obj/_cgo_export.c; do
cc $BUILDGO_CFLAGS -c $f -o ''${f}.o
done
cc $BUILDGO_CFLAGS -c $PWD/_obj/_cgo_main.c -o $PWD/_obj/_cgo_main.o
cc $BUILDGO_CFLAGS -o $PWD/_obj/_cgo_.o $PWD/_obj/_cgo_main.o $PWD/_obj/*.cgo2.c.o $BUILDGO_LDFLAGS
${go}/bin/go tool cgo -dynpackage ${packageName} -dynimport $PWD/_obj/_cgo_.o -dynout $PWD/_obj/_cgo_imports.go
EXTRAGO=$PWD/_obj/*.go
'';
cgoPack = ifCgo ''
${go}/bin/go tool pack r $out/${path}.a $PWD/_obj/*.cgo2.c.o $PWD/_obj/_cgo_export.c.o
'';
# The build steps below need to be executed conditionally for Go
# assembly if the analyser detected any *.s files.
#
# This is required for several popular packages (e.g. x/sys).
ifAsm = do: lib.optionalString (sfiles != [ ]) do;
asmBuild = ifAsm ''
${go}/bin/go tool asm -trimpath $PWD -I $PWD -I ${go}/share/go/pkg/include -D GOOS_linux -D GOARCH_amd64 -p ${path} -gensymabis -o ./symabis ${spaceOut sfiles}
${go}/bin/go tool asm -trimpath $PWD -I $PWD -I ${go}/share/go/pkg/include -D GOOS_linux -D GOARCH_amd64 -p ${path} -o ./asm.o ${spaceOut sfiles}
'';
asmLink = ifAsm "-symabis ./symabis -asmhdr $out/go_asm.h";
asmPack = ifAsm ''
${go}/bin/go tool pack r $out/${path}.a ./asm.o
'';
runCommand = if (cgofiles != [ ]) then runCommandCC else pkgs.runCommand;
gopkg = (runCommand "golib-${name}" {
buildInputs = cgodeps;
} ''
mkdir -p $out/${path}
EXTRAGO=""
${importcfgCmd { inherit name; deps = uniqueDeps; }}
${srcList path (map (s: "${s}") srcs)}
${asmBuild}
${cgoBuild}
${go}/bin/go tool compile -pack ${asmLink} -o $out/${path}.a -importcfg=importcfg -trimpath=$PWD -trimpath=${go} -trimpath=$out/${path} -p ${path} ${includeSources uniqueDeps} ${spaceOut (map (srcDest path) srcs)} $EXTRAGO
${asmPack}
${cgoPack}
'').overrideAttrs (_: {
passthru = {
inherit gopkg;
goDeps = uniqueDeps;
cgo = cgofiles != [ ];
cgoBuildInputs = cgodeps;
cgoLDFLAGS = cgoldflags;
goImportPath = path;
};
});
in
gopkg;
# Build a tree of Go libraries out of an external Go source
# directory that follows the standard Go layout and was not built
# with buildGo.nix.
#
# The derivation for each actual package will reside in an attribute
# named "gopkg", and an attribute named "gobin" for binaries.
external = import ./external { inherit pkgs program package; };
# Import support libraries needed for protobuf & gRPC support
protoLibs = import ./proto.nix {
inherit gopkgs;
};
# Build a Go library out of the specified protobuf definition.
proto = { name, proto ? null, protos ? [ proto ], path ? name, goPackage ? name, withGrpc ? false, extraSrcs ? [], extraDeps ? [] }:
let
protosDir = runCommand "protos" {} ''
mkdir $out
${lib.concatMapStrings (p: "cp ${p} $out/${baseNameOf p}\n") protos}
'';
mname = prefix: lib.concatMapStrings (p: "${prefix}M${baseNameOf p}=${path} ") protos;
in (makeOverridable package) {
inherit name path;
deps = [ protoLibs.goProto.proto.gopkg ] ++ extraDeps;
srcs = lib.concatMap (proto: lib.singleton (runCommand "goproto-${name}-${baseNameOf proto}.pb.go" {} ''
${protobuf}/bin/protoc \
-I ${protosDir} \
--plugin=${protoLibs.goProto.cmd.protoc-gen-go.gopkg}/bin/protoc-gen-go \
--go_out=. \
--go_opt=paths=source_relative \
${mname "--go_opt="} \
${protosDir}/${baseNameOf proto}
mv ./*.pb.go $out
'') ++ lib.optional withGrpc (runCommand "gogrpcproto-${name}-${baseNameOf proto}.pb.go" {} ''
${protobuf}/bin/protoc \
-I ${protosDir} \
--plugin=${protoLibs.goGrpc.cmd.protoc-gen-go-grpc.gopkg}/bin/protoc-gen-go-grpc \
--go-grpc_out=. \
--go-grpc_opt=paths=source_relative \
${mname "--go-grpc_opt="} \
${protosDir}/${baseNameOf proto}
mv ./*.pb.go $out 2>/dev/null || echo "package ${goPackage}" >> $out
'')) protos ++ extraSrcs;
};
# Build a Go library out of the specified gRPC definition.
grpc = { extraDeps ? [], ... }@args: proto (args // { withGrpc = true; extraDeps = extraDeps ++ [ protoLibs.goGrpc.gopkg ]; });
in
{
# Only the high-level builder functions are exposed, but made
# overrideable.
program = makeOverridable program;
package = makeOverridable package;
proto = makeOverridable proto;
grpc = makeOverridable grpc;
external = makeOverridable external;
}