image: Functions to search protected TLVs
This commit adds two sets of functions to the `image.Image` struct:
<verb>ProtTlvs<...>: Operates on protected TLVs only.
<verb>AllTlvs<...>: Operates on regulare and protected TLVs.
diff --git a/image/image.go b/image/image.go
index eb571eb..7cd1e1a 100644
--- a/image/image.go
+++ b/image/image.go
@@ -313,7 +313,125 @@
})
}
-// ProtTrailer constructs a protected ImageTrailer corresponding to the given image.
+// FindProtTlvIndicesIf searches an image for TLVs satisfying the given
+// predicate and returns their indices.
+func (img *Image) FindProtTlvIndicesIf(pred func(tlv ImageTlv) bool) []int {
+ var idxs []int
+
+ for i, tlv := range img.ProtTlvs {
+ if pred(tlv) {
+ idxs = append(idxs, i)
+ }
+ }
+
+ return idxs
+}
+
+// FindProtTlvIndices searches an image for TLVs of the specified type and
+// returns their indices.
+func (img *Image) FindProtTlvIndices(tlvType uint8) []int {
+ return img.FindProtTlvIndicesIf(func(tlv ImageTlv) bool {
+ return tlv.Header.Type == tlvType
+ })
+}
+
+// FindTlvIndices searches an image for TLVs satisfying the given predicate and
+// returns them.
+func (img *Image) FindProtTlvsIf(pred func(tlv ImageTlv) bool) []*ImageTlv {
+ var tlvs []*ImageTlv
+
+ idxs := img.FindProtTlvIndicesIf(pred)
+ for _, idx := range idxs {
+ tlvs = append(tlvs, &img.Tlvs[idx])
+ }
+
+ return tlvs
+}
+
+// FindProtTlvs retrieves all TLVs in an image's footer with the specified type.
+func (img *Image) FindProtTlvs(tlvType uint8) []*ImageTlv {
+ var tlvs []*ImageTlv
+
+ idxs := img.FindProtTlvIndices(tlvType)
+ for _, idx := range idxs {
+ tlvs = append(tlvs, &img.Tlvs[idx])
+ }
+
+ return tlvs
+}
+
+// FindProtUniqueTlv retrieves a TLV in an image's footer with the specified
+// type. It returns an error if there is more than one TLV with this type.
+func (i *Image) FindProtUniqueTlv(tlvType uint8) (*ImageTlv, error) {
+ tlvs := i.FindProtTlvs(tlvType)
+ if len(tlvs) == 0 {
+ return nil, nil
+ }
+ if len(tlvs) > 1 {
+ return nil, errors.Errorf("image contains %d TLVs with type %d",
+ len(tlvs), tlvType)
+ }
+
+ return tlvs[0], nil
+}
+
+// RemoveProtTlvsIf removes all TLVs from an image that satisfy the supplied
+// predicate. It returns a slice of the removed TLVs.
+func (i *Image) RemoveProtTlvsIf(pred func(tlv ImageTlv) bool) []ImageTlv {
+ rmed := []ImageTlv{}
+
+ for idx := 0; idx < len(i.ProtTlvs); {
+ tlv := i.ProtTlvs[idx]
+ if pred(tlv) {
+ rmed = append(rmed, tlv)
+ i.ProtTlvs = append(i.ProtTlvs[:idx], i.ProtTlvs[idx+1:]...)
+ } else {
+ idx++
+ }
+ }
+
+ return rmed
+}
+
+// RemoveProtTlvsWithType removes from an image all TLVs with the specified
+// type. It returns a slice of the removed TLVs.
+func (i *Image) RemoveProtTlvsWithType(tlvType uint8) []ImageTlv {
+ return i.RemoveProtTlvsIf(func(tlv ImageTlv) bool {
+ return tlv.Header.Type == tlvType
+ })
+}
+
+func (i *Image) FindAllTlvsIf(pred func(tlv ImageTlv) bool) []*ImageTlv {
+ regTlvs := i.FindTlvsIf(pred)
+ protTlvs := i.FindProtTlvsIf(pred)
+
+ return append(regTlvs, protTlvs...)
+}
+
+func (i *Image) FindAllTlvs(tlvType uint8) []*ImageTlv {
+ return i.FindAllTlvsIf(func(tlv ImageTlv) bool {
+ return tlv.Header.Type == tlvType
+ })
+}
+
+func (i *Image) FindAllUniqueTlv(tlvType uint8) (*ImageTlv, error) {
+ tlvs := i.FindAllTlvs(tlvType)
+
+ if len(tlvs) == 0 {
+ return nil, nil
+ }
+
+ if len(tlvs) > 1 {
+ return nil, errors.Errorf(
+ "image contains too many TLVs with type %d: have=%d want<=1",
+ tlvType, len(tlvs))
+ }
+
+ return tlvs[0], nil
+}
+
+// ProtTrailer constructs a protected ImageTrailer corresponding to the given
+// image.
func (img *Image) ProtTrailer() ImageTrailer {
trailer := ImageTrailer{
Magic: IMAGE_PROT_TRAILER_MAGIC,
