From 5ee1f125e59267d8dce4c22c7d030d0310eebbf3 Mon Sep 17 00:00:00 2001
From: Michael Lotz <mmlr@mlotz.ch>
Date: Wed, 21 Oct 2009 23:44:59 +0000
Subject: [PATCH] Make use of the wait status field so it can be provided in
 Notify() and then read out in the ConditionVariableEntry::WaitStatus(). That
 way you can notify with a specific status that can be read out on the other
 end.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@33718 a95241bf-73f2-0310-859d-f6bbb57e9c96
---
 headers/private/kernel/condition_variable.h | 23 +++++++++++++--------
 src/system/kernel/condition_variable.cpp    | 16 +++++++++-----
 2 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/headers/private/kernel/condition_variable.h b/headers/private/kernel/condition_variable.h
index 5f1a83f1e8..0f13257a12 100644
--- a/headers/private/kernel/condition_variable.h
+++ b/headers/private/kernel/condition_variable.h
@@ -32,7 +32,9 @@ public:
 			status_t			Wait(const void* object, uint32 flags = 0,
 									bigtime_t timeout = 0);
 
-	inline	ConditionVariable* Variable() const		{ return fVariable; }
+	inline	status_t			WaitStatus() const { return fWaitStatus; }
+
+	inline	ConditionVariable*	Variable() const { return fVariable; }
 
 private:
 	inline	void				AddToVariable(ConditionVariable* variable);
@@ -56,8 +58,10 @@ public:
 									const char* objectType);
 			void				Unpublish(bool threadsLocked = false);
 
-	inline	void				NotifyOne(bool threadsLocked = false);
-	inline	void				NotifyAll(bool threadsLocked = false);
+	inline	void				NotifyOne(bool threadsLocked = false,
+									status_t result = B_OK);
+	inline	void				NotifyAll(bool threadsLocked = false,
+									status_t result = B_OK);
 
 			void				Add(ConditionVariableEntry* entry);
 
@@ -72,8 +76,9 @@ public:
 			void				Dump() const;
 
 private:
-			void				_Notify(bool all, bool threadsLocked);
-			void				_NotifyChecked(bool all, status_t result);
+			void				_Notify(bool all, bool threadsLocked,
+									status_t result);
+			void				_NotifyLocked(bool all, status_t result);
 
 protected:
 			typedef DoublyLinkedList<ConditionVariableEntry> EntryList;
@@ -109,16 +114,16 @@ ConditionVariableEntry::~ConditionVariableEntry()
 
 
 inline void
-ConditionVariable::NotifyOne(bool threadsLocked)
+ConditionVariable::NotifyOne(bool threadsLocked, status_t result)
 {
-	_Notify(false, threadsLocked);
+	_Notify(false, threadsLocked, result);
 }
 
 
 inline void
-ConditionVariable::NotifyAll(bool threadsLocked)
+ConditionVariable::NotifyAll(bool threadsLocked, status_t result)
 {
-	_Notify(true, threadsLocked);
+	_Notify(true, threadsLocked, result);
 }
 
 
diff --git a/src/system/kernel/condition_variable.cpp b/src/system/kernel/condition_variable.cpp
index 4777ad2edd..d27a41124e 100644
--- a/src/system/kernel/condition_variable.cpp
+++ b/src/system/kernel/condition_variable.cpp
@@ -241,7 +241,7 @@ ConditionVariable::Unpublish(bool threadsLocked)
 	fObjectType = NULL;
 
 	if (!fEntries.IsEmpty())
-		_NotifyChecked(true, B_ENTRY_NOT_FOUND);
+		_NotifyLocked(true, B_ENTRY_NOT_FOUND);
 }
 
 
@@ -293,14 +293,20 @@ ConditionVariable::Dump() const
 
 
 void
-ConditionVariable::_Notify(bool all, bool threadsLocked)
+ConditionVariable::_Notify(bool all, bool threadsLocked, status_t result)
 {
 	InterruptsLocker _;
 	SpinLocker threadLocker(threadsLocked ? NULL : &gThreadSpinlock);
 	SpinLocker locker(sConditionVariablesLock);
 
-	if (!fEntries.IsEmpty())
-		_NotifyChecked(all, B_OK);
+	if (!fEntries.IsEmpty()) {
+		if (result > B_OK) {
+			panic("tried to notify with invalid result %ld\n", result);
+			result = B_ERROR;
+		}
+
+		_NotifyLocked(all, result);
+	}
 }
 
 
@@ -308,7 +314,7 @@ ConditionVariable::_Notify(bool all, bool threadsLocked)
 	thread lock held.
 */
 void
-ConditionVariable::_NotifyChecked(bool all, status_t result)
+ConditionVariable::_NotifyLocked(bool all, status_t result)
 {
 	// dequeue and wake up the blocked threads
 	while (ConditionVariableEntry* entry = fEntries.RemoveHead()) {