1 files changed, 74 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/util/OsUtils.java b/src/main/java/com/google/devtools/build/lib/util/OsUtils.java
new file mode 100644
index 0000000000..fa12f59682
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/util/OsUtils.java
@@ -0,0 +1,74 @@
+// Copyright 2014 Google Inc. All rights reserved.
+//
+// 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 com.google.devtools.build.lib.util;
+
+import com.google.devtools.build.lib.vfs.PathFragment;
+
+/**
+ * Operating system-specific utilities.
+ */
+public final class OsUtils {
+
+  private static final String EXECUTABLE_EXTENSION = OS.getCurrent() == OS.WINDOWS ? ".exe" : "";
+
+  // Utility class.
+  private OsUtils() {
+  }
+
+  /**
+   * Returns the extension used for executables on the current platform (.exe
+   * for Windows, empty string for others).
+   */
+  public static String executableExtension() {
+    return EXECUTABLE_EXTENSION;
+  }
+
+  /**
+   * Loads JNI libraries, if necessary under the current platform.
+   */
+  public static void maybeForceJNI(PathFragment installBase) {
+    if (jniLibsAvailable()) {
+      forceJNI(installBase);
+    }
+  }
+
+  private static boolean jniLibsAvailable() {
+    // JNI libraries work fine on Windows, but at the moment we are not using any.
+    return OS.getCurrent() != OS.WINDOWS;
+  }
+
+  // Force JNI linking at a moment when we have 'installBase' handy, and print
+  // an informative error if it fails.
+  private static void forceJNI(PathFragment installBase) {
+    try {
+      ProcessUtils.getpid(); // force JNI initialization
+    } catch (UnsatisfiedLinkError t) {
+      System.err.println("JNI initialization failed: " + t.getMessage() + ".  "
+          + "Possibly your installation has been corrupted; "
+          + "if this problem persists, try 'rm -fr " + installBase + "'.");
+      throw t;
+    }
+  }
+
+  /**
+   * Returns the PID of the current process, or -1 if not available.
+   */
+  public static int getpid() {
+    if (jniLibsAvailable()) {
+      return ProcessUtils.getpid();
+    }
+    return -1;
+  }
+}