dbus: revamp fd passing support for i/o restrictions

    
Encapsulate file descriptor validity checking and status in the companion FileDescriptor class so callers can do descriptor checking in a context where i/o is allowed.
    
Update the debug daemon client support to validate the pipe descriptors in a worker thread so it is not done on the UI thread.

BUG=126142

TEST=new unit tests + collect trace data on chrome os and verify no assert is triggered

Review URL: https://chromiumcodereview.appspot.com/10382021

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@136331 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 9 insertions, 0 deletions

diff --git a/dbus/message_unittest.cc b/dbus/message_unittest.cc
index 424b50a..9d87c2a 100644
--- a/dbus/message_unittest.cc
+++ b/dbus/message_unittest.cc
@@ -107,6 +107,11 @@ TEST(MessageTest, AppendAndPopFileDescriptor) {
 
   // Append stdout.
   dbus::FileDescriptor temp(1);
+  // Descriptor should not be valid until checked.
+  ASSERT_FALSE(temp.is_valid());
+  // NB: thread IO requirements not relevant for unit tests.
+  temp.CheckValidity();
+  ASSERT_TRUE(temp.is_valid());
   writer.AppendFileDescriptor(temp);
 
   dbus::FileDescriptor fd_value;
@@ -115,6 +120,10 @@ TEST(MessageTest, AppendAndPopFileDescriptor) {
   ASSERT_TRUE(reader.HasMoreData());
   ASSERT_TRUE(reader.PopFileDescriptor(&fd_value));
   ASSERT_FALSE(reader.HasMoreData());
+  // Descriptor is not valid until explicitly checked.
+  ASSERT_FALSE(fd_value.is_valid());
+  fd_value.CheckValidity();
+  ASSERT_TRUE(fd_value.is_valid());
 
   // Stdout should be returned but we cannot check the descriptor
   // value because stdout will be dup'd.  Instead check st_rdev