Add FirebirdConf class.

android/embedded/src/main/java/org/firebirdsql/android/embedded/FirebirdConf.kt

@@ -0,0 +1,78 @@
+package org.firebirdsql.android.embedded
+
+import android.content.Context
+import android.system.ErrnoException
+import android.system.Os
+import android.util.Log
+import java.io.File
+import java.io.FileOutputStream
+import java.io.IOException
+
+
+public object FirebirdConf {
+    private const val TAG = "FirebirdAndroid"
+
+    @JvmStatic
+    @Throws(IOException::class)
+    public fun extractAssets(context: Context, force: Boolean = true) {
+        val firebirdRootPath = File(context.filesDir, "firebird")
+
+        if (!force && firebirdRootPath.exists())
+            return;
+
+        val firebirdTempRootPath = File(context.filesDir, "firebird.tmp")
+
+        if (firebirdTempRootPath.exists())
+            deleteDirectory(firebirdTempRootPath)
+
+        firebirdTempRootPath.mkdir()
+
+        val firebirdTmpPath = File(firebirdTempRootPath, "tmp")
+        firebirdTmpPath.mkdirs()
+
+        val firebirdLockPath = File(firebirdTempRootPath, "lock")
+        firebirdLockPath.mkdirs()
+
+        val assetManager = context.assets
+        val buffer = ByteArray(1024)
+
+        for (asset in assetManager.list("firebird")!!) {
+            Log.d(TAG, "Extracting Firebird asset: $asset")
+
+            assetManager.open("firebird/$asset").use { input ->
+                FileOutputStream(File(firebirdTempRootPath, asset)).use { output ->
+                    var len: Int
+                    while (input.read(buffer).also { len = it } > 0)
+                        output.write(buffer, 0, len)
+                    output.flush()
+                }
+            }
+        }
+
+        if (firebirdRootPath.exists())
+            deleteDirectory(firebirdRootPath)
+
+        firebirdTempRootPath.renameTo(firebirdRootPath);
+    }
+
+    @JvmStatic
+    @Throws(ErrnoException::class)
+    public fun setEnv(context: Context) {
+        val firebirdRootPath = File(context.filesDir, "firebird")
+        val firebirdTmpPath = File(firebirdRootPath, "tmp")
+        val firebirdLockPath = File(firebirdRootPath, "lock")
+
+        Os.setenv("FIREBIRD", firebirdRootPath.absolutePath, true)
+        Os.setenv("FIREBIRD_TMP", firebirdTmpPath.absolutePath, true)
+        Os.setenv("FIREBIRD_LOCK", firebirdLockPath.absolutePath, true)
+    }
+
+    private fun deleteDirectory(directory: File) {
+        for (file in directory.listFiles()) {
+            if (file.isDirectory)
+                deleteDirectory(file)
+            else
+                file.delete()
+        }
+    }
+}