format/commitgraph: Split into ./read and ./ v0.1.60

1 files changed, 32 insertions, 0 deletions

diff --git a/format/commitgraph/read/open_single.go b/format/commitgraph/read/open_single.go
new file mode 100644
index 00000000..f20cd166
--- /dev/null
+++ b/format/commitgraph/read/open_single.go
@@ -0,0 +1,32 @@
+package read
+
+import (
+	"os"
+
+	"codeberg.org/lindenii/furgit/internal/intconv"
+	"codeberg.org/lindenii/furgit/objectid"
+)
+
+func openSingle(root *os.Root, algo objectid.Algorithm) (*Reader, error) {
+	graph, err := openLayer(root, "info/commit-graph", algo)
+	if err != nil {
+		return nil, err
+	}
+
+	graph.baseCount = 0
+	graph.globalFrom = 0
+
+	hashVersion, err := intconv.Uint32ToUint8(algo.PackHashID())
+	if err != nil {
+		return nil, err
+	}
+
+	out := &Reader{
+		algo:        algo,
+		hashVersion: hashVersion,
+		layers:      []layer{*graph},
+		total:       graph.numCommits,
+	}
+
+	return out, nil
+}