internal/rosa: initramfs artifact

This constructs a single-program initramfs and populates /dev/null so the runtime does not throw if the kernel fails to set up console.

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

internal/rosa/all.go

@@ -10,7 +10,17 @@ import (
 type PArtifact int
 
 const (
-	ACL PArtifact = iota
+	// ImageInitramfs is the Rosa OS initramfs archive.
+	ImageInitramfs PArtifact = iota
+
+	// Kernel is the generic Rosa OS Linux kernel.
+	Kernel
+	// KernelHeaders is an installation of kernel headers for [Kernel].
+	KernelHeaders
+	// KernelSource is a writable kernel source tree installed to [AbsUsrSrc].
+	KernelSource
+
+	ACL
 	ArgpStandalone
 	Attr
 	Autoconf
@@ -42,9 +52,6 @@ const (
 	Hakurei
 	HakureiDist
 	IniConfig
-	Kernel
-	KernelHeaders
-	KernelSource
 	Kmod
 	LibXau
 	Libcap
@@ -148,6 +155,12 @@ func (t Toolchain) Load(p PArtifact) pkg.Artifact {
 // ResolveName returns a [PArtifact] by name.
 func ResolveName(name string) (p PArtifact, ok bool) {
 	p, ok = map[string]PArtifact{
+		"initramfs-image": ImageInitramfs,
+
+		"kernel":         Kernel,
+		"kernel-headers": KernelHeaders,
+		"kernel-source":  KernelSource,
+
 		"acl":               ACL,
 		"argp-standalone":   ArgpStandalone,
 		"attr":              Attr,
@@ -180,9 +193,6 @@ func ResolveName(name string) (p PArtifact, ok bool) {
 		"hakurei":           Hakurei,
 		"hakurei-dist":      HakureiDist,
 		"iniconfig":         IniConfig,
-		"kernel":            Kernel,
-		"kernel-headers":    KernelHeaders,
-		"kernel-source":     KernelSource,
 		"kmod":              Kmod,
 		"libXau":            LibXau,
 		"libcap":            Libcap,

internal/rosa/images.go

@@ -0,0 +1,16 @@
+package rosa
+
+import "hakurei.app/internal/pkg"
+
+func (t Toolchain) newImageInitramfs() pkg.Artifact {
+	return t.New("initramfs", TNoToolchain, []pkg.Artifact{
+		t.Load(Zstd),
+		t.Load(Hakurei),
+	}, nil, nil, `
+cd "$(mktemp -d)"
+cp /system/libexec/hakurei/earlyinit init
+((find . | cpio -R 0:0 -o) && (cd / && echo dev/null | cpio -R 0:0 -o)) | \
+	zstd -19 > /work/initramfs.zst
+`)
+}
+func init() { artifactsF[ImageInitramfs] = Toolchain.newImageInitramfs }