[NaCl SDK] nacl_io: Add initial implementations of kill and signal

native_client_sdk/src/libraries/nacl_io/kernel_object.h

Index: native_client_sdk/src/libraries/nacl_io/kernel_object.h
diff --git a/native_client_sdk/src/libraries/nacl_io/kernel_object.h b/native_client_sdk/src/libraries/nacl_io/kernel_object.h
index 036ff64e666f87d517268eb4b30222170c4f1233..83a41a0e64148af520b96eda8989e375e7a3f99f 100644
--- a/native_client_sdk/src/libraries/nacl_io/kernel_object.h
+++ b/native_client_sdk/src/libraries/nacl_io/kernel_object.h
@@ -12,6 +12,7 @@
 #include <vector>
 
 #include "nacl_io/error.h"
+#include "nacl_io/event_emitter.h"
 #include "nacl_io/kernel_handle.h"
 #include "nacl_io/mount.h"
 #include "nacl_io/mount_node.h"
@@ -26,7 +27,7 @@ namespace nacl_io {
 // All Kernel locks are private to ensure the lock order.
 //
 // All calls are assumed to be a relative path.
-class KernelObject {
+class KernelObject : public EventEmitter {
  public:
   typedef std::vector<ScopedKernelHandle> HandleMap_t;
   typedef std::map<std::string, ScopedMount> MountMap_t;
@@ -75,6 +76,16 @@ class KernelObject {
   // Returns parts of the absolute path for the given relative path
   Path GetAbsParts(const std::string& path);
 
+  // From EventEmitter.  The KernelObject emitters events in order
+  // to inturrupt anything waiting in select()/poll() when kill()
+  // is called.  It has no readable or wriable state and also no
+  // meaningful type.
+  uint32_t GetEventStatus() { return 0; }
+  int GetType() {
+    // For lack of a better type, report socket to signify it can be in an
+    // used to signal.
+    return S_IFSOCK;
+  }
 private:
   std::string cwd_;
   std::vector<int> free_fds_;
@@ -93,6 +104,9 @@ private:
   DISALLOW_COPY_AND_ASSIGN(KernelObject);
 };
 
+typedef sdk_util::ScopedRef<KernelObject> ScopedKernelObject;
+
+
 }  // namespace nacl_io
 
 #endif  // LIBRARIES_NACL_IO_KERNEL_OBJECT_H_