add genFID to PathInfo

1 files changed, 15 insertions, 0 deletions

diff --git a/src/main/kotlin/PathInfo.kt b/src/main/kotlin/PathInfo.kt
index 4981662..c803e17 100644
--- a/src/main/kotlin/PathInfo.kt
+++ b/src/main/kotlin/PathInfo.kt
@@ -68,4 +68,19 @@ class PathInfo() {
     fun getAllPaths(): Set<Path> {
         return this.paths.toSet()
     }
+
+    /**
+     * Generate a new FID which is not already in use.
+     *
+     * @return The new FID.
+     * @throws IllegalStateException if there is no available FID.
+     */
+    fun genFID(): UInt {
+        for (newFid in 0u..UInt.MAX_VALUE) {
+            if (findByFID(newFid) == null) {
+                return newFid
+            }
+        }
+        throw IllegalStateException()
+    }
 }
\ No newline at end of file