internal/rosa: include iana-etc

This is used by some programs and will likely end up in the Rosa OS system image anyway.

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

internal/rosa/etc.go

@@ -1,7 +1,10 @@
 package rosa
 
 import (
+	"errors"
+	"io"
 	"os"
+	"syscall"
 
 	"hakurei.app/internal/pkg"
 )
@@ -9,10 +12,13 @@ import (
 // cureEtc contains deterministic elements of /etc, made available as part of
 // [Toolchain]. This silences test suites expecting certain standard files to be
 // available in /etc.
-type cureEtc struct{}
+type cureEtc struct {
+	// Optional via newIANAEtc.
+	iana pkg.Artifact
+}
 
 // Cure writes hardcoded configuration to files under etc.
-func (cureEtc) Cure(t *pkg.TContext) (err error) {
+func (a cureEtc) Cure(t *pkg.FContext) (err error) {
 	etc := t.GetWorkDir().Append("etc")
 	if err = os.MkdirAll(etc.String(), 0700); err != nil {
 		return
@@ -36,6 +42,44 @@ nobody:x:65534:
 			return
 		}
 	}
+
+	if a.iana != nil {
+		iana, _ := t.GetArtifact(a.iana)
+
+		buf := make([]byte, syscall.Getpagesize()<<3)
+		for _, name := range []string{
+			"protocols",
+			"services",
+		} {
+			var dst, src *os.File
+			if dst, err = os.OpenFile(
+				etc.Append(name).String(),
+				syscall.O_CREAT|syscall.O_EXCL|syscall.O_WRONLY,
+				0400,
+			); err != nil {
+				return
+			}
+
+			if src, err = os.Open(
+				iana.Append(name).String(),
+			); err != nil {
+				_ = dst.Close()
+				return
+			}
+
+			_, err = io.CopyBuffer(dst, src, buf)
+			closeErrs := [...]error{
+				dst.Close(),
+				src.Close(),
+			}
+			if err != nil {
+				return
+			} else if err = errors.Join(closeErrs[:]...); err != nil {
+				return
+			}
+		}
+	}
+
 	return os.Chmod(etc.String(), 0500)
 }
 
@@ -45,8 +89,27 @@ func (cureEtc) Kind() pkg.Kind { return kindEtc }
 // Params is a noop.
 func (cureEtc) Params(*pkg.IContext) {}
 
-// Dependencies returns a nil slice.
-func (cureEtc) Dependencies() []pkg.Artifact { return nil }
+// Dependencies returns a slice containing the backing iana-etc release.
+func (a cureEtc) Dependencies() []pkg.Artifact {
+	if a.iana != nil {
+		return []pkg.Artifact{a.iana}
+	}
+	return nil
+}
 
 // String returns a hardcoded reporting name.
 func (cureEtc) String() string { return "cure-etc" }
+
+// newIANAEtc returns an unpacked iana-etc release.
+func newIANAEtc() pkg.Artifact {
+	const (
+		version  = "20251215"
+		checksum = "kvKz0gW_rGG5QaNK9ZWmWu1IEgYAdmhj_wR7DYrh3axDfIql_clGRHmelP7525NJ"
+	)
+	return pkg.NewHTTPGetTar(
+		nil, "https://github.com/Mic92/iana-etc/releases/download/"+
+			version+"/iana-etc-"+version+".tar.gz",
+		mustDecode(checksum),
+		pkg.TarGzip,
+	)
+}

internal/rosa/rosa.go

@@ -216,7 +216,7 @@ ln -vs ../usr/bin /work/bin
 		boot := t - 1
 		musl, compilerRT, runtimes, clang := boot.NewLLVM()
 		support = slices.Concat([]pkg.Artifact{
-			cureEtc{},
+			cureEtc{newIANAEtc()},
 			musl,
 			compilerRT,
 			runtimes,