validation and casefolding of names

1 files changed, 41 insertions, 0 deletions

diff --git a/server/validate/validate.go b/server/validate/validate.go
new file mode 100644
index 0000000..4415557
--- /dev/null
+++ b/server/validate/validate.go
@@ -0,0 +1,41 @@
+package validate
+
+import (
+	"strings"
+	"unicode"
+)
+
+func Name(name string) bool {
+	if len(Fold(name)) == 0 || len(name) >= 256 {
+		return false
+	}
+	for _, r := range name {
+		if unicode.IsControl(r) {
+			return false
+		}
+	}
+	return true
+}
+
+func Fold(s string) string {
+	var sb strings.Builder
+	var wasSpace bool
+	for _, r := range s {
+		for r < unicode.SimpleFold(r) {
+			r = unicode.SimpleFold(r)
+		}
+		if !unicode.IsPrint(r) {
+			continue
+		}
+		if r == ' ' {
+			if wasSpace {
+				continue
+			}
+			wasSpace = true
+		} else {
+			wasSpace = false
+		}
+		sb.WriteRune(r)
+	}
+	return strings.TrimSpace(sb.String())
+}