Lockfile implementation (#24)

Implemented lockfile synchronization

To be used instead of or in conjunction with existing events to coordinate launching and discovery of server instances

1 files changed, 11 insertions, 5 deletions

diff --git a/zenutil/include/zenutil/zenserverprocess.h b/zenutil/include/zenutil/zenserverprocess.h
index 09728aa1a..8a4f9604d 100644
--- a/zenutil/include/zenutil/zenserverprocess.h
+++ b/zenutil/include/zenutil/zenserverprocess.h
@@ -94,17 +94,22 @@ public:
 
 	struct ZenServerEntry
 	{
+		// NOTE: any changes to this should consider backwards compatibility
+		//       which means you should not rearrange members only potentially
+		//       add something to the end or use a different mechanism for
+		//       additional state. For example, you can use the session ID
+		//       to introduce additional named objects
 		std::atomic<uint32_t> Pid;
 		std::atomic<uint16_t> ListenPort;
 		std::atomic<uint16_t> Flags;
 		uint8_t				  SessionId[12];
-		std::atomic<uint32_t> SponsorPids[32];
+		std::atomic<uint32_t> SponsorPids[8];
 		uint8_t				  Padding[12];
-		uint8_t				  Padding2[96];
 
 		enum class FlagsEnum : uint16_t
 		{
-			kShutdownPlease = 1 << 0
+			kShutdownPlease = 1 << 0,
+			kIsReady		= 1 << 1,
 		};
 
 		FRIEND_ENUM_CLASS_FLAGS(FlagsEnum);
@@ -112,10 +117,11 @@ public:
 		Oid	 GetSessionId() const { return Oid::FromMemory(SessionId); }
 		void Reset();
 		void SignalShutdownRequest();
+		void SignalReady();
 		bool AddSponsorProcess(uint32_t Pid);
 	};
 
-	static_assert(sizeof(ZenServerEntry) == 256);
+	static_assert(sizeof(ZenServerEntry) == 64);
 
 	void						  Initialize();
 	[[nodiscard]] bool			  InitializeReadOnly();
@@ -128,7 +134,7 @@ public:
 private:
 	void*			m_hMapFile		= nullptr;
 	ZenServerEntry* m_Data			= nullptr;
-	int				m_MaxEntryCount = 131072 / sizeof(ZenServerEntry);
+	int				m_MaxEntryCount = 65536 / sizeof(ZenServerEntry);
 	ZenServerEntry* m_OurEntry		= nullptr;
 	bool			m_IsReadOnly	= true;
 };