Merge pull request #286 from tri-adam/issue-285

fix: preserve arch in SetPrimPart

Author: tri-adam

pkg/sif/create.go

@@ -622,60 +622,52 @@ func (f *FileImage) SetPrimPart(id uint32, opts ...SetOpt) error {
 return fmt.Errorf("%w", errNotPartition)
 }
 
-fs, pt, arch, err := descr.getPartitionMetadata()
-if err != nil {
+var p partition
+if err := descr.getExtra(binaryUnmarshaler{&p}); err != nil {
 return fmt.Errorf("%w", err)
 }
 
 // if already primary system partition, nothing to do
-if pt == PartPrimSys {
+if p.Parttype == PartPrimSys {
 return nil
 }
 
-if pt != PartSystem {
+if p.Parttype != PartSystem {
 return fmt.Errorf("%w", errNotSystem)
 }
 
-olddescr, err := f.getDescriptor(WithPartitionType(PartPrimSys))
-if err != nil && !errors.Is(err, ErrObjectNotFound) {
-return fmt.Errorf("%w", err)
-}
-extra := partition{
-Fstype: fs,
-Parttype: PartPrimSys,
-}
-copy(extra.Arch[:], arch)
-
-if err := descr.setExtra(extra); err != nil {
-return fmt.Errorf("%w", err)
-}
-
-descr.ModifiedAt = so.t.Unix()
-
-if olddescr != nil {
-oldfs, _, oldarch, err := olddescr.getPartitionMetadata()
-if err != nil {
+// If there is currently a primary system partition, update it.
+if d, err := f.getDescriptor(WithPartitionType(PartPrimSys)); err == nil {
+var p partition
+if err := d.getExtra(binaryUnmarshaler{&p}); err != nil {
 return fmt.Errorf("%w", err)
 }
 
-oldextra := partition{
-Fstype: oldfs,
-Parttype: PartSystem,
-Arch: getSIFArch(oldarch),
-}
+p.Parttype = PartSystem
 
-if err := olddescr.setExtra(oldextra); err != nil {
+if err := d.setExtra(p); err != nil {
 return fmt.Errorf("%w", err)
 }
 
-olddescr.ModifiedAt = so.t.Unix()
+d.ModifiedAt = so.t.Unix()
+} else if !errors.Is(err, ErrObjectNotFound) {
+return fmt.Errorf("%w", err)
 }
 
+// Update the descriptor of the new primary system partition.
+p.Parttype = PartPrimSys
+
+if err := descr.setExtra(p); err != nil {
+return fmt.Errorf("%w", err)
+}
+
+descr.ModifiedAt = so.t.Unix()
+
 if err := f.writeDescriptors(); err != nil {
 return fmt.Errorf("%w", err)
 }
 
-f.h.Arch = getSIFArch(arch)
+f.h.Arch = p.Arch
 f.h.ModifiedAt = so.t.Unix()
 
 if err := f.writeHeader(); err != nil {