internal/pkg: optionally register binfmt

This transparently supports curing foreign exec artifacts.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/rosa/all.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
+	"runtime"
 	"strconv"
 	"sync"
 
@@ -347,6 +348,9 @@ var (
 	// artifactsOnce is for lazy initialisation of artifacts.
 	artifactsOnce [_toolchainEnd][len(artifactsM)]sync.Once
 
+	// arch is the target architecture.
+	arch = runtime.GOARCH
+
 	// presetOpts globally modifies behaviour of presets.
 	presetOpts int
 )
@@ -358,6 +362,9 @@ const (
 	OptLLVMNoLTO
 )
 
+// Arch returns the target architecture.
+func Arch() string { return arch }
+
 // Flags returns the current preset flags
 func Flags() int { return presetOpts }
 
@@ -367,7 +374,12 @@ func zero[T any](p *T) { var v T; *p = v }
 // DropCaches arranges for all cached [pkg.Artifact] to be freed some time after
 // it returns. Must not be used concurrently with any other function from this
 // package.
-func DropCaches(flags int) {
+func DropCaches(targetArch string, flags int) {
+	if targetArch == "" {
+		targetArch = runtime.GOARCH
+	}
+
+	arch = targetArch
 	presetOpts = flags
 	zero(&artifacts)
 	zero(&artifactsOnce)

internal/rosa/all_test.go

@@ -20,8 +20,8 @@ func TestLoad(t *testing.T) {
 }
 
 func BenchmarkAll(b *testing.B) {
-	flags := rosa.Flags()
-	b.Cleanup(func() { rosa.DropCaches(flags) })
+	arch, flags := rosa.Arch(), rosa.Flags()
+	b.Cleanup(func() { rosa.DropCaches(arch, flags) })
 
 	for b.Loop() {
 		for i := range rosa.PresetEnd {
@@ -29,7 +29,7 @@ func BenchmarkAll(b *testing.B) {
 		}
 
 		b.StopTimer()
-		rosa.DropCaches(0)
+		rosa.DropCaches("", 0)
 		b.StartTimer()
 	}
 }

internal/rosa/busybox.go

@@ -105,7 +105,7 @@ func newBusyboxBin() pkg.Artifact {
 	}
 
 	return pkg.NewExec(
-		"busybox-bin-"+version, nil, pkg.ExecTimeoutMax, false,
+		"busybox-bin-"+version, arch, nil, pkg.ExecTimeoutMax, false,
 		fhs.AbsRoot, []string{
 			"PATH=/system/bin",
 		},

internal/rosa/rosa.go

@@ -327,7 +327,7 @@ mkdir -vp /work/system/bin
 	}
 
 	return pkg.NewExec(
-		name, knownChecksum, pkg.ExecTimeoutMax, flag&TExclusive != 0,
+		name, arch, knownChecksum, pkg.ExecTimeoutMax, flag&TExclusive != 0,
 		fhs.AbsRoot, env,
 		AbsSystem.Append("bin", "sh"),
 		[]string{"sh", absCureScript.String()},

internal/rosa/rosa_test.go

@@ -28,7 +28,7 @@ var (
 )
 
 func TestMain(m *testing.M) {
-	rosa.DropCaches(rosa.OptLLVMNoLTO)
+	rosa.DropCaches("", rosa.OptLLVMNoLTO)
 	container.TryArgv0(nil)
 
 	code := m.Run()
@@ -94,14 +94,14 @@ func TestCureAll(t *testing.T) {
 }
 
 func BenchmarkStage3(b *testing.B) {
-	flags := rosa.Flags()
-	b.Cleanup(func() { rosa.DropCaches(flags) })
+	arch, flags := rosa.Arch(), rosa.Flags()
+	b.Cleanup(func() { rosa.DropCaches(arch, flags) })
 
 	for b.Loop() {
 		rosa.Std.Load(rosa.LLVM)
 
 		b.StopTimer()
-		rosa.DropCaches(0)
+		rosa.DropCaches("", 0)
 		b.StartTimer()
 	}
 }