Fix token_to_piece implementation in Swift

examples/batched.swift/Sources/main.swift

@@ -242,6 +242,16 @@ private func token_to_piece(token: llama_token, buffer: inout [CChar]) -> String
             Int32(result.count)
         )
         assert(check == nTokens)
+    } else if nTokens > 8 {
+        result.removeAll()
+        result = [CChar](repeating: 0, count: nTokens)
+        let check = llama_token_to_piece(
+            model,
+            token,
+            &result,
+            Int32(result.count)
+        )
+        assert(check == nTokens)
     } else {
         result.removeLast(result.count - Int(nTokens))
     }

examples/llama.swiftui/llama.cpp.swift/LibLlama.swift

@@ -165,7 +165,18 @@ actor LlamaContext {
         let result = UnsafeMutablePointer<Int8>.allocate(capacity: 8)
         result.initialize(repeating: Int8(0), count: 8)
 
-        let _ = llama_token_to_piece(model, token, result, 8)
+        let nTokens = llama_token_to_piece(model, token, result, 8)
+
+        if nTokens > 8 {
+            result.removeAll()
+            result = [CChar](repeating: 0, count: nTokens)
+            _ = llama_token_to_piece(
+                model,
+                token,
+                &result,
+                Int32(result.count)
+            )
+        }
 
         let resultStr = String(cString: result)