lib/api: Expose `blocksHash` in file info (#8810)

This adds the BlocksHash field from the FileInfo to our API output. It
can be useful for debugging, or for external tools. I'm intentionally
leaving it as an opaque base64 string because no meaning should be
derived from it: it's just a string.

3 files changed, 10 insertions, 0 deletions

diff --git a/lib/api/api.go b/lib/api/api.go
index 456123fdc2..6f9451dcc5 100644
--- a/lib/api/api.go
+++ b/lib/api/api.go
@@ -1828,6 +1828,7 @@ func fileIntfJSONMap(f protocol.FileIntf) map[string]interface{} {
 		"localFlags":    f.FileLocalFlags(),
 		"platform":      f.PlatformData(),
 		"inodeChange":   f.InodeChangeTime(),
+		"blocksHash":    f.FileBlocksHash(),
 	}
 	if f.HasPermissionBits() {
 		out["permissions"] = fmt.Sprintf("%#o", f.FilePermissions())
diff --git a/lib/db/structs.go b/lib/db/structs.go
index daa514fab7..8c3c1f39a4 100644
--- a/lib/db/structs.go
+++ b/lib/db/structs.go
@@ -133,6 +133,10 @@ func (f FileInfoTruncated) InodeChangeTime() time.Time {
 	return time.Unix(0, f.InodeChangeNs)
 }
 
+func (f FileInfoTruncated) FileBlocksHash() []byte {
+	return f.BlocksHash
+}
+
 func (f FileInfoTruncated) ConvertToIgnoredFileInfo() protocol.FileInfo {
 	file := f.copyToFileInfo()
 	file.SetIgnored()
diff --git a/lib/protocol/bep_extensions.go b/lib/protocol/bep_extensions.go
index 2290f2cce9..4ee23adc5a 100644
--- a/lib/protocol/bep_extensions.go
+++ b/lib/protocol/bep_extensions.go
@@ -46,6 +46,7 @@ type FileIntf interface {
 	ModTime() time.Time
 	PlatformData() PlatformData
 	InodeChangeTime() time.Time
+	FileBlocksHash() []byte
 }
 
 func (Hello) Magic() uint32 {
@@ -170,6 +171,10 @@ func (f FileInfo) InodeChangeTime() time.Time {
 	return time.Unix(0, f.InodeChangeNs)
 }
 
+func (f FileInfo) FileBlocksHash() []byte {
+	return f.BlocksHash
+}
+
 // WinsConflict returns true if "f" is the one to choose when it is in
 // conflict with "other".
 func WinsConflict(f, other FileIntf) bool {