From e4e7aeb39d75c768c42418611cae6f9aee64dfe7 Mon Sep 17 00:00:00 2001
From: UnicornFreedom <dmitry.zhidenkov@gmail.com>
Date: Thu, 16 Jun 2022 19:00:33 +0200
Subject: [PATCH] Fix #16: crash when trying to clean native DLLs on Windows

---
 .gitignore                                    |  1 +
 .../scala/ocelot/desktop/ui/UiHandler.scala   | 30 ++++++++++++-------
 2 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/.gitignore b/.gitignore
index 54cb580..6725c54 100644
--- a/.gitignore
+++ b/.gitignore
@@ -38,6 +38,7 @@ cacerts
 /*.dll
 /*.so
 /*.dylib
+/natives/
 
 # Log files
 *.log
diff --git a/src/main/scala/ocelot/desktop/ui/UiHandler.scala b/src/main/scala/ocelot/desktop/ui/UiHandler.scala
index 45ffe6a..48d106e 100644
--- a/src/main/scala/ocelot/desktop/ui/UiHandler.scala
+++ b/src/main/scala/ocelot/desktop/ui/UiHandler.scala
@@ -122,10 +122,14 @@ object UiHandler extends Logging {
     }
   }
 
-  var tempDir: String = _
+  var nativeLibrariesDir: String = _
 
   private def loadLibraries(): Unit = {
-    tempDir = Files.createTempDirectory("ocelot-desktop").toString
+    // we cannot remove DLL files on Windows after they were loaded by Ocelot
+    // therefore we will create them in local directory and keep for future
+    nativeLibrariesDir = if (SystemUtils.IS_OS_WINDOWS)
+      Paths.get(SystemUtils.USER_DIR, "natives").toString
+      else Files.createTempDirectory("ocelot-desktop").toString
 
     val arch = System.getProperty("os.arch")
     val is64bit = arch.startsWith("amd64")
@@ -146,16 +150,19 @@ object UiHandler extends Logging {
       throw new Exception("Unsupported OS")
 
     for (lib <- libs) {
-      val source = getClass.getResourceAsStream("/" + lib)
-      val dest = new File(Paths.get(tempDir, lib).toString)
-      val output = new FileOutputStream(dest)
-      output.getChannel.transferFrom(Channels.newChannel(source), 0, Long.MaxValue)
-      output.flush()
-      output.close()
-      source.close()
+      val dest = new File(Paths.get(nativeLibrariesDir, lib).toString)
+      if (!dest.exists()) {
+        val source = getClass.getResourceAsStream("/" + lib)
+        if (!dest.getParentFile.exists()) dest.getParentFile.mkdirs()
+        val output = new FileOutputStream(dest)
+        output.getChannel.transferFrom(Channels.newChannel(source), 0, Long.MaxValue)
+        output.flush()
+        output.close()
+        source.close()
+      }
     }
 
-    System.setProperty("org.lwjgl.librarypath", tempDir)
+    System.setProperty("org.lwjgl.librarypath", nativeLibrariesDir)
   }
 
   private def loadIcons(): Unit = {
@@ -238,7 +245,8 @@ object UiHandler extends Logging {
     if (!audioDisabled)
       AL.destroy()
 
-    FileUtils.deleteDirectory(new File(tempDir))
+    if (!SystemUtils.IS_OS_WINDOWS)
+      FileUtils.deleteDirectory(new File(nativeLibrariesDir))
   }
 
   private def update(): Unit = {