1 files changed, 132 insertions, 0 deletions
diff --git a/kamon-system-metrics/src/main/scala/kamon/system/sigar/SigarLoader.scala b/kamon-system-metrics/src/main/scala/kamon/system/sigar/SigarLoader.scala
new file mode 100644
index 00000000..0c78504e
--- /dev/null
+++ b/kamon-system-metrics/src/main/scala/kamon/system/sigar/SigarLoader.scala
@@ -0,0 +1,132 @@
+/*
+ * =========================================================================================
+ * Copyright © 2013-2014 the kamon project <http://kamon.io/>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
+ * either express or implied. See the License for the specific language governing permissions
+ * and limitations under the License.
+ * =========================================================================================
+ */
+
+package kamon.system.sigar
+
+import java.io._
+import java.util
+import java.util.logging.Logger
+import java.util.{ ArrayList, List }
+
+import kamon.system.SynchronizedSigar
+import org.hyperic.sigar.SigarProxy
+
+import scala.annotation.tailrec
+import scala.collection.JavaConversions._
+import scala.io.Source
+
+object SigarLoader {
+
+  val Version = "1.6.4"
+  val JavaLibraryPath = "java.library.path"
+  val TmpDir = "java.io.tmpdir"
+  val IndexFile = "/kamon/system/sigar/index"
+  val UsrPathField = "usr_paths"
+
+  private val log = Logger.getLogger("SigarLoader")
+
+  def sigarProxy = init(new File(System.getProperty(TmpDir)))
+
+  private[sigar] def init(baseTmp: File): SigarProxy = {
+    val tmpDir = createTmpDir(baseTmp)
+    for (lib ← loadIndex) copy(lib, tmpDir)
+
+    attachToLibraryPath(tmpDir)
+
+    try {
+      val sigar = new SynchronizedSigar()
+      sigar.getPid
+      sigar
+    } catch {
+      case t: Throwable ⇒ {
+        log.severe("Failed to load sigar")
+        throw new RuntimeException(t)
+      }
+    }
+  }
+
+  private[sigar] val usrPathField = {
+    val usrPathField = classOf[ClassLoader].getDeclaredField(UsrPathField)
+    usrPathField.setAccessible(true)
+    usrPathField
+  }
+
+  private[sigar] def attachToLibraryPath(dir: File): Unit = {
+    val dirAbsolute = dir.getAbsolutePath
+    System.setProperty(JavaLibraryPath, newLibraryPath(dirAbsolute))
+    var paths = usrPathField.get(null).asInstanceOf[Array[String]]
+    if (paths == null) paths = new Array[String](0)
+    for (path ← paths) if (path == dirAbsolute) return
+    val newPaths = util.Arrays.copyOf(paths, paths.length + 1)
+    newPaths(newPaths.length - 1) = dirAbsolute
+    usrPathField.set(null, newPaths)
+  }
+
+  private[sigar] def newLibraryPath(dirAbsolutePath: String): String = {
+    Option(System.getProperty(JavaLibraryPath)).fold(dirAbsolutePath)(oldValue ⇒ s"$dirAbsolutePath${File.pathSeparator}$oldValue")
+  }
+
+  private[sigar] def copy(lib: String, tmpDir: File) {
+    val target = new File(tmpDir, lib)
+    if (target.exists()) return
+    write(classOf[Loader].getResourceAsStream(lib), target)
+  }
+
+  private[sigar] def createTmpDir(baseTmp: File): File = {
+    val tmpDir = new File(baseTmp, s"sigar-$Version")
+    if (!tmpDir.exists()) {
+      if (!tmpDir.mkdirs()) throw new RuntimeException(s"Could not create temp sigar directory: ${tmpDir.getAbsolutePath}")
+    }
+    if (!tmpDir.isDirectory) throw new RuntimeException(s"sigar temp directory path is not a directory: ${tmpDir.getAbsolutePath}")
+    if (!tmpDir.canWrite()) throw new RuntimeException(s"sigar temp directory not writeable: ${tmpDir.getAbsolutePath}")
+    tmpDir
+  }
+
+  private[sigar] def loadIndex(): List[String] = {
+    val libs = new ArrayList[String]()
+    val is = classOf[Loader].getResourceAsStream(IndexFile)
+
+    for (line ← Source.fromInputStream(is).getLines()) {
+      val currentLine = line.trim()
+      libs add currentLine
+    }
+    libs
+  }
+
+  private[sigar] def write(input: InputStream, to: File) {
+    val out = new FileOutputStream(to)
+    try {
+      transfer(input, out)
+    } finally {
+      out.close()
+    }
+  }
+
+  private[sigar] def transfer(input: InputStream, out: OutputStream) {
+    val buffer = new Array[Byte](8192)
+
+    @tailrec def transfer() {
+      val read = input.read(buffer)
+      if (read >= 0) {
+        out.write(buffer, 0, read)
+        transfer()
+      }
+    }
+    transfer()
+  }
+
+  class Loader private[sigar]
+}