Fixed a bug that caused a crash if the PersistentData folder didn't exist at startup. Added a hardcoded endpoint for EQI when using any method other than EnVisen's.

Author: ThomasOldham

lib/Eqi.go

@@ -4,6 +4,7 @@ import (
 	"errors"
 	"github.com/polyverse/ropoly/lib/eqi"
 	"github.com/polyverse/ropoly/lib/types"
+	"math"
 	"net/url"
 )
 
@@ -12,6 +13,8 @@ func DirectEqi(f1 types.Fingerprint, f2 types.Fingerprint, eqiFunc string, form
 		return eqi.OriginalEnvisenEqi(f1, f2), nil
 	}
 
+	normalized := form.Get("normalized") == "true"
+
 	function := directEqiFuncs[eqiFunc]
 	if function == nil {
 		return types.EntropyQualityIndex(0), errors.New("EQI function not recognized.")
@@ -21,7 +24,7 @@ func DirectEqi(f1 types.Fingerprint, f2 types.Fingerprint, eqiFunc string, form
 	if err != nil {
 		return types.EntropyQualityIndex(0), err
 	}
-	return normalizeEqi(eqi), nil
+	return normalizeEqi(eqi, eqiFunc, normalized), nil
 }
 
 type directEqiFunc func(types.Fingerprint, types.Fingerprint, url.Values) (float64, error)
@@ -33,6 +36,10 @@ var directEqiFuncs = map[string]directEqiFunc {
 	"highest-offset-count": eqi.HighestOffsetCountEqi,
 }
 
-func normalizeEqi(eqi float64) types.EntropyQualityIndex {
-	return types.EntropyQualityIndex(100.0 * (1.0 - eqi))
+func normalizeEqi(eqi float64, eqiFunc string, normalized bool) types.EntropyQualityIndex {
+	ret := 100.0 * (1.0 - eqi)
+	if normalized {
+		ret = 1.7626080809865 * (math.Pow(1.04139221012755, ret) - 1)
+	}
+	return types.EntropyQualityIndex(ret)
 }

lib/Filepaths.go

@@ -18,6 +18,9 @@ func EnsureDirectory(path string) error {
 
 // https://stackoverflow.com/questions/10510691/how-to-check-whether-a-file-or-directory-exists/10510718
 func Exists(path string) (bool, error) {
+	if path == "" {
+		return true, nil
+	}
 	_, err := os.Stat(path)
 	if err == nil {
 		return true, nil
@@ -52,6 +55,9 @@ func windDirectoryStack(stack *[]string) error {
 		}
 		if !exists {
 			lastSlashIndex := strings.LastIndex(peek(stack), "/")
+			if lastSlashIndex == -1 {
+				lastSlashIndex = 0
+			}
 			push(stack, peek(stack)[:lastSlashIndex])
 		}
 	}