Support for custom library path. (#82)

samples/SkijaInjectSample/build.gradle.kts

@@ -52,6 +52,7 @@ val additionalArguments = mutableMapOf<String, String>()
 
 val casualRun = tasks.named<JavaExec>("run") {
     systemProperty("skiko.fps.enabled", "true")
+    // Use systemProperty("skiko.library.path", "/tmp") to test loader.
     System.getProperties().entries
         .associate {
             (it.key as String) to (it.value as String)

skiko/src/jvmMain/kotlin/org/jetbrains/skiko/Library.kt

@@ -9,6 +9,7 @@ import java.nio.file.StandardCopyOption
 object Library {
     private var loaded = false
 
+    private val skikoLibraryPath = System.getProperty("skiko.library.path")
     private val cacheRoot = "${System.getProperty("user.home")}/.skiko/"
 
     private fun loadOrGet(cacheDir: File, path: String, resourceName: String, isLibrary: Boolean) {
@@ -33,24 +34,30 @@ object Library {
     fun load() {
         if (loaded) return
 
-        val resourcePath = "/"
         val name = "skiko-$hostId"
         val platformName = System.mapLibraryName(name)
 
+        if (skikoLibraryPath != null) {
+            val library = File(File(skikoLibraryPath), platformName)
+            System.load(library.absolutePath)
+        } else {
+            val resourcePath = "/"
             val hashResourceStream = Library::class.java.getResourceAsStream(
-            "$resourcePath$platformName.sha256") ?: throw LibraryLoadException(
+                "$resourcePath$platformName.sha256"
+            ) ?: throw LibraryLoadException(
                 "Cannot find $platformName.sha256, proper native dependency missing."
             )
             val hash = hashResourceStream.use {
                 BufferedReader(InputStreamReader(it)).lines().toArray()[0] as String
             }
-        val cacheDir = File("$cacheRoot/$hash")
+            val cacheDir = File(File(cacheRoot), hash)
             cacheDir.mkdirs()
             loadOrGet(cacheDir, resourcePath, platformName, true)
             val loadIcu = hostOs.isWindows
             if (loadIcu) {
                 loadOrGet(cacheDir, resourcePath, "icudtl.dat", false)
             }
+        }
 
         // TODO move properties to SkikoProperties
         Setup.init(