Fix toPointer() function and added Gradle utility scripts (#22)

toPointer() allocating one bte less, resulting in missing string termination char in native memory, leading to random issues in JVM.

nuke-gradle.bat

@@ -0,0 +1,11 @@
+@echo off
+for /r %%i in (.) do (
+    if /i "%%~nxi"==".gradle" (
+        echo Deleting: %%i
+        rd /s /q "%%i"
+    )
+    if /i "%%~nxi"=="build" (
+        echo Deleting: %%i
+        rd /s /q "%%i"
+    )
+)

nuke-gradle.sh

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+find . \( -name ".gradle" -o -name "build" \) -type d -exec rm -rf {} \;

src/jvmCommonMain/kotlin/com/github/lamba92/leveldb/jvm/JvmLevelDB.kt

@@ -21,8 +21,8 @@ public class JvmLevelDB internal constructor(
             val errPtr = PointerByReference()
             val writeOptions = leveldb_writeoptions_create()
             leveldb_writeoptions_set_sync(writeOptions, sync.toByte())
-            val keyPointer = key.toByteArray().toPointer()
-            val valuePointer = value.toByteArray().toPointer()
+            val keyPointer = key.toPointer()
+            val valuePointer = value.toPointer()
             leveldb_put(
                 db = nativeDatabase,
                 options = writeOptions,
@@ -56,7 +56,7 @@ public class JvmLevelDB internal constructor(
             val errPtr = PointerByReference()
             val writeOptions = leveldb_writeoptions_create()
             leveldb_writeoptions_set_sync(writeOptions, sync.toByte())
-            val keyPointer = key.toByteArray().toPointer()
+            val keyPointer = key.toPointer()
             leveldb_delete(
                 db = nativeDatabase,
                 options = writeOptions,
@@ -83,8 +83,8 @@ public class JvmLevelDB internal constructor(
             for (operation in operations) {
                 when (operation) {
                     is LevelDBBatchOperation.Put -> {
-                        val keyPointer = operation.key.toByteArray().toPointer()
-                        val valuePointer = operation.value.toByteArray().toPointer()
+                        val keyPointer = operation.key.toPointer()
+                        val valuePointer = operation.value.toPointer()
                         leveldb_writebatch_put(
                             batch = nativeBatch,
                             key = keyPointer,
@@ -97,7 +97,7 @@ public class JvmLevelDB internal constructor(
                     }
 
                     is LevelDBBatchOperation.Delete -> {
-                        val keyPointer = operation.key.toByteArray().toPointer()
+                        val keyPointer = operation.key.toPointer()
                         leveldb_writebatch_delete(
                             batch = nativeBatch,
                             key = keyPointer,
@@ -147,12 +147,10 @@ public class JvmLevelDB internal constructor(
         val startPointer =
             start
                 .takeIf { it.isNotEmpty() }
-                ?.toByteArray()
                 ?.toPointer()
         val endPointer =
             end
                 .takeIf { it.isNotEmpty() }
-                ?.toByteArray()
                 ?.toPointer()
         LibLevelDB.leveldb_compact_range(
             db = nativeDatabase,

src/jvmCommonMain/kotlin/com/github/lamba92/leveldb/jvm/JvmUtills.kt

@@ -9,7 +9,7 @@ import com.sun.jna.NativeLong
 import com.sun.jna.ptr.LongByReference
 import com.sun.jna.ptr.PointerByReference
 
-internal fun ByteArray.toPointer() = Memory(size.toLong()).apply { write(0, this@toPointer, 0, this@toPointer.size) }
+internal fun String.toPointer() = Memory(length.toLong() + 1L).also { it.setString(0L, this) }
 
 internal fun LibLevelDB.leveldb_t.get(
     verifyChecksums: Boolean,
@@ -24,7 +24,7 @@ internal fun LibLevelDB.leveldb_t.get(
     if (snapshot != null) {
         leveldb_readoptions_set_snapshot(nativeReadOptions, snapshot)
     }
-    val keyPointer = key.toByteArray().toPointer()
+    val keyPointer = key.toPointer()
     val valueLengthPointer = LongByReference()
     val value =
         leveldb_get(
@@ -85,7 +85,7 @@ internal fun LibLevelDB.leveldb_t.asSequence(
         when (from) {
             null -> leveldb_iter_seek_to_first(iterator)
             else -> {
-                val fromPointer = from.toByteArray().toPointer()
+                val fromPointer = from.toPointer()
                 leveldb_iter_seek(iterator, fromPointer, from.length.toNativeLong())
                 fromPointer.close()
             }