Add ElementOffset field

remko · Jun 12, 2023 · 94fa39a · 94fa39a
1 parent f0fb81b
commit 94fa39a
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Showing 2 changed files with 79 additions and 60 deletions.
diff --git a/mkvparse.go b/mkvparse.go
@@ -41,9 +41,10 @@ const (
 // ElementInfo contains information about an element encountered in
 // the stream, and is passed to the handler by the parser on parse events.
 type ElementInfo struct {
- Offset int64
- Size int64
- Level int
+ ElementOffset int64
+ Offset int64 // Data offset
+ Size int64
+ Level int
 }
 
 // Handler declares an interface for handling parse events
@@ -147,14 +148,14 @@ func parseElement(reader io.Reader, currentOffset int64, level int, unknownSizeP
  if unknownSizeParent != -1 && isFinishUnknownSizeBlock(id, unknownSizeParent) {
  return 0, id, idCount, nil
  }
- count, err = parseElementAfterID(reader, id, currentOffset+idCount, level, unknownSizeParent, handler)
+ count, err = parseElementAfterID(reader, id, currentOffset, currentOffset+idCount, level, unknownSizeParent, handler)
  if err != nil {
  return -1, -1, -1, err
  }
  return count + idCount, -1, -1, nil
 }
 
-func parseElementAfterID(reader io.Reader, id ElementID, currentOffset int64, level int, unknownSizeParent ElementID, handler Handler) (count int64, err error) {
+func parseElementAfterID(reader io.Reader, id ElementID, elementOffset int64, currentOffset int64, level int, unknownSizeParent ElementID, handler Handler) (count int64, err error) {
  size, sizeCount, all1, err := readVarInt(reader)
  if err != nil {
  return -1, err
@@ -164,9 +165,10 @@ func parseElementAfterID(reader io.Reader, id ElementID, currentOffset int64, le
  dataOffset := currentOffset + sizeCount
  count = sizeCount + size
  info := ElementInfo{
- Offset: dataOffset,
- Size: size,
- Level: level,
+ ElementOffset: elementOffset,
+ Offset: dataOffset,
+ Size: size,
+ Level: level,
  }
  if typ == masterType {
  if all1 {
@@ -196,7 +198,7 @@ func parseElementAfterID(reader io.Reader, id ElementID, currentOffset int64, le
  if nextID == -1 {
  return count, nil
  }
- nextcount, err := parseElementAfterID(reader, nextID, dataOffset+count+nextIDCount, level, unknownSizeParent, handler)
+ nextcount, err := parseElementAfterID(reader, nextID, dataOffset+count, dataOffset+count+nextIDCount, level, unknownSizeParent, handler)
  if err != nil {
  return -1, err
  }

diff --git a/mkvparse_test.go b/mkvparse_test.go
@@ -113,27 +113,30 @@ func TestParseElement(t *testing.T) {
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: 3,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: 3,
+ Level: 0,
  },
  MasterBeginEvent{},
  },
  {
  TimecodeElement,
  ElementInfo{
- Offset: 7,
- Size: 1,
- Level: 1,
+ ElementOffset: 5,
+ Offset: 7,
+ Size: 1,
+ Level: 1,
  },
  int64(0x3),
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: 3,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: 3,
+ Level: 0,
  },
  MasterEndEvent{},
  },
@@ -168,72 +171,80 @@ func TestParseElement(t *testing.T) {
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: -1,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: -1,
+ Level: 0,
  },
  MasterBeginEvent{},
  },
  {
  TimecodeElement,
  ElementInfo{
- Offset: 7,
- Size: 1,
- Level: 1,
+ ElementOffset: 5,
+ Offset: 7,
+ Size: 1,
+ Level: 1,
  },
  int64(0x3),
  },
  {
  TimecodeElement,
  ElementInfo{
- Offset: 10,
- Size: 1,
- Level: 1,
+ ElementOffset: 8,
+ Offset: 10,
+ Size: 1,
+ Level: 1,
  },
  int64(0x3),
  },
  {
  TimecodeElement,
  ElementInfo{
- Offset: 13,
- Size: 1,
- Level: 1,
+ ElementOffset: 11,
+ Offset: 13,
+ Size: 1,
+ Level: 1,
  },
  int64(0x3),
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: -1,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: -1,
+ Level: 0,
  },
  MasterEndEvent{},
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 20,
- Size: 3,
- Level: 0,
+ ElementOffset: 15,
+ Offset: 20,
+ Size: 3,
+ Level: 0,
  },
  MasterBeginEvent{},
  },
  {
  TimecodeElement,
  ElementInfo{
- Offset: 22,
- Size: 1,
- Level: 1,
+ ElementOffset: 20,
+ Offset: 22,
+ Size: 1,
+ Level: 1,
  },
  int64(0x3),
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 20,
- Size: 3,
- Level: 0,
+ ElementOffset: 15,
+ Offset: 20,
+ Size: 3,
+ Level: 0,
  },
  MasterEndEvent{},
  },
@@ -293,18 +304,20 @@ func TestParseMaster_Skips(t *testing.T) {
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: 3,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: 3,
+ Level: 0,
  },
  MasterBeginEvent{},
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: 3,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: 3,
+ Level: 0,
  },
  MasterEndEvent{},
  },
@@ -325,36 +338,40 @@ func TestParseMaster_Skips(t *testing.T) {
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: -1,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: -1,
+ Level: 0,
  },
  MasterBeginEvent{},
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 5,
- Size: -1,
- Level: 0,
+ ElementOffset: 0,
+ Offset: 5,
+ Size: -1,
+ Level: 0,
  },
  MasterEndEvent{},
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 20,
- Size: 3,
- Level: 0,
+ ElementOffset: 15,
+ Offset: 20,
+ Size: 3,
+ Level: 0,
  },
  MasterBeginEvent{},
  },
  {
  ClusterElement,
  ElementInfo{
- Offset: 20,
- Size: 3,
- Level: 0,
+ ElementOffset: 15,
+ Offset: 20,
+ Size: 3,
+ Level: 0,
  },
  MasterEndEvent{},
  },