From 8f70192bf3f4adcb10b6f80d01dbef197bdbf205 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Magiera?= <magik6k@gmail.com>
Date: Tue, 19 May 2020 18:11:56 +0200
Subject: [PATCH] Missing stuff

---
 ffiwrapper/unseal_ranges.go | 24 ++++++++++++++++++++++++
 storiface/ffi.go            |  5 +++++
 2 files changed, 29 insertions(+)
 create mode 100644 ffiwrapper/unseal_ranges.go
 create mode 100644 storiface/ffi.go

diff --git a/ffiwrapper/unseal_ranges.go b/ffiwrapper/unseal_ranges.go
new file mode 100644
index 000000000..873ac45d0
--- /dev/null
+++ b/ffiwrapper/unseal_ranges.go
@@ -0,0 +1,24 @@
+package ffiwrapper
+
+import (
+	"golang.org/x/xerrors"
+
+	"github.com/filecoin-project/go-bitfield/rle"
+	"github.com/filecoin-project/specs-actors/actors/abi"
+)
+
+// merge gaps between ranges which are close to each other
+//  TODO: more benchmarking to come up with more optimal number
+const mergeGaps = 32 << 20
+
+// TODO const expandRuns = 16 << 20 // unseal more than requested for future requests
+
+func computeUnsealRanges(unsealed rlepluslazy.RunIterator, offset UnpaddedByteIndex, size abi.UnpaddedPieceSize) (rlepluslazy.RunIterator, error) {
+	todo := pieceRun(offset, size)
+	todo, err := rlepluslazy.Subtract(todo, unsealed)
+	if err != nil {
+		return nil, xerrors.Errorf("compute todo-unsealed: %w", err)
+	}
+
+	return rlepluslazy.JoinClose(todo, mergeGaps)
+}
diff --git a/storiface/ffi.go b/storiface/ffi.go
new file mode 100644
index 000000000..354b1e9c4
--- /dev/null
+++ b/storiface/ffi.go
@@ -0,0 +1,5 @@
+package storiface
+
+import "errors"
+
+var ErrSectorNotFound = errors.New("sector not found")