openfiletable: add inummap

Generates unique inode numbers for files on different
devices.

https://github.com/rfjakob/gocryptfs/issues/435

1 files changed, 81 insertions, 0 deletions

diff --git a/internal/openfiletable/inummap_test.go b/internal/openfiletable/inummap_test.go
new file mode 100644
index 0000000..85438bd
--- /dev/null
+++ b/internal/openfiletable/inummap_test.go
@@ -0,0 +1,81 @@
+package openfiletable
+
+import (
+	"sync"
+	"testing"
+)
+
+func TestTranslate(t *testing.T) {
+	const baseDev = 12345
+	m := NewInumMap(baseDev)
+
+	q := QIno{Dev: baseDev, Ino: 1}
+	out := m.Translate(q)
+	if out != 1 {
+		t.Errorf("expected 1, got %d", out)
+	}
+	q.Ino = inumTranslateBase
+	out = m.Translate(q)
+	if out < inumTranslateBase {
+		t.Errorf("got %d", out)
+	}
+	out2 := m.Translate(q)
+	if out2 != out {
+		t.Errorf("unstable mapping: %d %d", out2, out)
+	}
+}
+
+func TestTranslateStress(t *testing.T) {
+	const baseDev = 12345
+	m := NewInumMap(baseDev)
+	var wg sync.WaitGroup
+	wg.Add(4)
+	go func() {
+		q := QIno{Dev: baseDev}
+		for i := uint64(1); i <= 10000; i++ {
+			q.Ino = i
+			out := m.Translate(q)
+			if out != i {
+				t.Fail()
+			}
+		}
+		wg.Done()
+	}()
+	go func() {
+		q := QIno{Dev: baseDev}
+		for i := uint64(1); i <= 10000; i++ {
+			q.Ino = inumTranslateBase + i
+			out := m.Translate(q)
+			if out < inumTranslateBase {
+				t.Fail()
+			}
+		}
+		wg.Done()
+	}()
+	go func() {
+		q := QIno{Dev: 9999999}
+		for i := uint64(1); i <= 10000; i++ {
+			q.Ino = i
+			out := m.Translate(q)
+			if out < inumTranslateBase {
+				t.Fail()
+			}
+		}
+		wg.Done()
+	}()
+	go func() {
+		q := QIno{Dev: 4444444}
+		for i := uint64(1); i <= 10000; i++ {
+			q.Ino = i
+			out := m.Translate(q)
+			if out < inumTranslateBase {
+				t.Fail()
+			}
+		}
+		wg.Done()
+	}()
+	wg.Wait()
+	if m.Count() != 30000 {
+		t.Fail()
+	}
+}