Detect underflow when calculating unused space (#5758)

* Detect underflow when calculating unused space

* Detect underflow when calculating unused space

1 files changed, 78 insertions, 0 deletions

diff --git a/weed/storage/disk_location_test.go b/weed/storage/disk_location_test.go
new file mode 100644
index 000000000..d105a477f
--- /dev/null
+++ b/weed/storage/disk_location_test.go
@@ -0,0 +1,78 @@
+package storage
+
+import (
+	"testing"
+	"time"
+
+	"github.com/seaweedfs/seaweedfs/weed/storage/backend"
+	"github.com/seaweedfs/seaweedfs/weed/storage/needle"
+	"github.com/seaweedfs/seaweedfs/weed/util"
+)
+
+type (
+	mockBackendStorageFile struct {
+		backend.DiskFile
+
+		datSize int64
+	}
+)
+
+func (df *mockBackendStorageFile) GetStat() (datSize int64, modTime time.Time, err error) {
+	return df.datSize, time.Now(), nil
+}
+
+type (
+	mockNeedleMapper struct {
+		NeedleMap
+
+		idxSize uint64
+	}
+)
+
+func (nm *mockNeedleMapper) IndexFileSize() (idxSize uint64) {
+	return nm.idxSize
+}
+
+func TestUnUsedSpace(t *testing.T) {
+	minFreeSpace := util.MinFreeSpace{Type: util.AsPercent, Percent: 1, Raw: "1"}
+
+	diskLocation := DiskLocation{
+		Directory:              "/test/",
+		DirectoryUuid:          "1234",
+		IdxDirectory:           "/test/",
+		DiskType:               "hdd",
+		MaxVolumeCount:         0,
+		OriginalMaxVolumeCount: 0,
+		MinFreeSpace:           minFreeSpace,
+	}
+	diskLocation.volumes = make(map[needle.VolumeId]*Volume)
+
+	volumes := [3]*Volume{
+		{dir: diskLocation.Directory, dirIdx: diskLocation.IdxDirectory, Collection: "", Id: 0, DataBackend: &mockBackendStorageFile{datSize: 990}, nm: &mockNeedleMapper{idxSize: 10}},
+		{dir: diskLocation.Directory, dirIdx: diskLocation.IdxDirectory, Collection: "", Id: 1, DataBackend: &mockBackendStorageFile{datSize: 990}, nm: &mockNeedleMapper{idxSize: 10}},
+		{dir: diskLocation.Directory, dirIdx: diskLocation.IdxDirectory, Collection: "", Id: 2, DataBackend: &mockBackendStorageFile{datSize: 990}, nm: &mockNeedleMapper{idxSize: 10}},
+	}
+
+	for i, vol := range volumes {
+		diskLocation.SetVolume(needle.VolumeId(i), vol)
+	}
+
+	// Testing when there's still space
+	unUsedSpace := diskLocation.UnUsedSpace(1200)
+	if unUsedSpace != 600 {
+		t.Errorf("unUsedSpace incorrect: %d != %d", unUsedSpace, 1500)
+	}
+
+	// Testing when there's exactly 0 space
+	unUsedSpace = diskLocation.UnUsedSpace(1000)
+	if unUsedSpace != 0 {
+		t.Errorf("unUsedSpace incorrect: %d != %d", unUsedSpace, 0)
+	}
+
+	// Testing when there's negative free space
+	unUsedSpace = diskLocation.UnUsedSpace(900)
+	if unUsedSpace != 0 {
+		t.Errorf("unUsedSpace incorrect: %d != %d", unUsedSpace, 0)
+	}
+
+}