dbus: add support for passing file descriptors

dbus/message.h

Index: dbus/message.h
diff --git a/dbus/message.h b/dbus/message.h
index 3a28fb0b57ebc6ba03da251821d9cf4946526f30..f7fd2634383dd23898dcd5ffaccea80886c9d3be 100644
--- a/dbus/message.h
+++ b/dbus/message.h
@@ -11,6 +11,7 @@
 #include <dbus/dbus.h>
 
 #include "base/basictypes.h"
+#include "dbus/file_descriptor.h"
 #include "dbus/object_path.h"
 
 namespace google {
@@ -67,6 +68,9 @@ class Message {
     STRUCT = DBUS_TYPE_STRUCT,
     DICT_ENTRY = DBUS_TYPE_DICT_ENTRY,
     VARIANT = DBUS_TYPE_VARIANT,
+#if defined(DBUS_TYPE_UNIX_FD)

[satorux1, 2012/03/28 00:32:43]

Please add some comment that DBUS_TYPE_UNIX_FD is not defined in older versions
of D-bus. Would be nice if we can say it's added in the version xxx.

[Sam Leffler, 2012/03/28 17:28:09]

Done.

+    UNIX_FD = DBUS_TYPE_UNIX_FD,
+#endif
   };
 
   // Returns the type of the message. Returns MESSAGE_INVALID if
@@ -268,6 +272,7 @@ class MessageWriter {
   void AppendDouble(double value);
   void AppendString(const std::string& value);
   void AppendObjectPath(const ObjectPath& value);
+  void AppendFileDescriptor(const FileDescriptor& value);
 
   // Opens an array. The array contents can be added to the array with
   // |sub_writer|. The client code must close the array with
@@ -377,6 +382,7 @@ class MessageReader {
   bool PopDouble(double* value);
   bool PopString(std::string* value);
   bool PopObjectPath(ObjectPath* value);
+  bool PopFileDescriptor(FileDescriptor* value);
 
   // Sets up the given message reader to read an array at the current
   // iterator position.