4 This is a simple streaming file format for representing a diff between
5 two snapshots (or a snapshot and the head) of an RBD image.
15 Every record has a one byte "tag" that identifies the record type,
16 followed by some other data.
18 Metadata records come in the first part of the image. Order is not
19 important, as long as all the metadata records come before the data
26 - le32: snap name length
33 - le32: snap name length
40 - le64: (ending) image size
45 These records come in the second part of the sequence.
53 - length bytes of actual data
80 Every record has a one byte "tag" that identifies the record type,
81 followed by length of data, and then some other data.
83 Metadata records come in the first part of the image. Order is not
84 important, as long as all the metadata records come before the data
87 In v2, we have the following metadata in each section:
92 In this way, we can skip the unrecognized tag.
98 - le64: length of appending data (4 + length)
99 - le32: snap name length
106 - le64: length of appending data (4 + length)
107 - le32: snap name length
114 - le64: length of appending data (8)
115 - le64: (ending) image size
120 These records come in the second part of the sequence.
126 - le64: length of appending data (8 + 8 + length)
129 - length bytes of actual data
135 - le64: length of appending data (8 + 8)