Release v0.1.0

vendor/github.com/lightninglabs/neutrino/headerfs/truncate.go

@@ -0,0 +1,38 @@
+// +build !windows
+
+package headerfs
+
+import "fmt"
+
+// singleTruncate truncates a single header from the end of the header file.
+// This can be used in the case of a re-org to remove the last header from the
+// end of the main chain.
+//
+// TODO(roasbeef): define this and the two methods above on a headerFile
+// struct?
+func (h *headerStore) singleTruncate() error {
+	// In order to truncate the file, we'll need to grab the absolute size
+	// of the file as it stands currently.
+	fileInfo, err := h.file.Stat()
+	if err != nil {
+		return err
+	}
+	fileSize := fileInfo.Size()
+
+	// Next, we'll determine the number of bytes we need to truncate from
+	// the end of the file.
+	var truncateLength int64
+	switch h.indexType {
+	case Block:
+		truncateLength = 80
+	case RegularFilter:
+		truncateLength = 32
+	default:
+		return fmt.Errorf("unknown index type: %v", h.indexType)
+	}
+
+	// Finally, we'll use both of these values to calculate the new size of
+	// the file and truncate it accordingly.
+	newSize := fileSize - truncateLength
+	return h.file.Truncate(newSize)
+}