Mojo: Add debug-only checks to Waiter that check that Init() has been called.

(And fix a test that didn't follow the contract properly.)

R=davemoore@chromium.org

Review URL: https://codereview.chromium.org/28983006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229889 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 12 insertions, 0 deletions

diff --git a/mojo/system/waiter.cc b/mojo/system/waiter.cc
index 6dda21f..754ece1 100644
--- a/mojo/system/waiter.cc
+++ b/mojo/system/waiter.cc
@@ -14,6 +14,9 @@ namespace system {
 
 Waiter::Waiter()
     : cv_(&lock_),
+#ifndef NDEBUG
+      initialized_(false),
+#endif
       awoken_(false),
       wait_result_(MOJO_RESULT_INTERNAL) {
 }
@@ -22,6 +25,9 @@ Waiter::~Waiter() {
 }
 
 void Waiter::Init() {
+#ifndef NDEBUG
+  initialized_ = true;
+#endif
   awoken_ = false;
   // NOTE(vtl): If performance ever becomes an issue, we can disable the setting
   // of |wait_result_| (except the first one in |Awake()|) in Release builds.
@@ -32,6 +38,12 @@ void Waiter::Init() {
 MojoResult Waiter::Wait(MojoDeadline deadline) {
   base::AutoLock locker(lock_);
 
+#ifndef NDEBUG
+  DCHECK(initialized_);
+  // It'll need to be re-initialized after this.
+  initialized_ = false;
+#endif
+
   // Fast-path the already-awoken case:
   if (awoken_) {
     DCHECK_NE(wait_result_, MOJO_RESULT_INTERNAL);