fixed various issues in the handle system with cloning

fixed plugins being able to free each other's handles

--HG--
extra : convert_revision : svn%3A39bc706e-5318-0410-9160-8a85361fbb7c/trunk%40264

core/interfaces/IHandleSys.h

@@ -42,13 +42,15 @@ namespace SourceMod
 		HandleError_Access,			/* No access permitted to free this handle */
 		HandleError_Limit,			/* The limited number of handles has been reached */
 		HandleError_Identity,		/* The identity token was not usable */
+		HandleError_Owner,			/* Owners do not match for this operation */
 	};
 
 	enum HandleAccessRight
 	{
 		HandleAccess_Create,		/* TYPE: Instances can be created by other objects (this makes it searchable) */
 		HandleAccess_Read,			/* HANDLES: Can be read by other objects */
-		HandleAccess_Delete,		/* HANDLES: Can be deleted by other objects */
+		HandleAccess_IdentDelete,	/* HANDLES: Can be deleted by other identities */
+		HandleAccess_OwnerDelete,	/* HANDLES: Can be deleted by other owners */
 		HandleAccess_Inherit,		/* TYPE: Can be inherited by new types */
 		HandleAccess_Clone,			/* HANDLES: Can be cloned */
 		/* ------------- */
@@ -62,9 +64,10 @@ namespace SourceMod
 			owner = NULL;
 			access[HandleAccess_Create] = true;
 			access[HandleAccess_Read] = true;
-			access[HandleAccess_Delete] = true;
+			access[HandleAccess_IdentDelete] = true;
 			access[HandleAccess_Inherit] = true;
 			access[HandleAccess_Clone] = true;
+			access[HandleAccess_OwnerDelete] = false;
 		}
 		IdentityToken_t *owner;				/* Owner of the handle */
 		bool access[HandleAccess_TOTAL];	/* World access rights */
@@ -166,7 +169,7 @@ namespace SourceMod
 		 * 
 		 * @param type		Type to use on the handle.
 		 * @param object	Object to bind to the handle.
-		 * @param owner		Owner for the handle.
+		 * @param owner		Owner for the handle.  NULL means anonymous (no owner).
 		 * @param ident		Identity token if any security rights are needed.
 		 * @return			A new Handle_t, or 0 on failure.
 		 */
@@ -196,10 +199,11 @@ namespace SourceMod
 		 * only perform any further action if the counter hits 0.
 		 *
 		 * @param type		Handle_t identifier to destroy.
+		 * @param owner		Owner of handle (NULL for none).
 		 * @param ident		Identity token, for destroying secure handles (NULL for none).
 		 * @return			A HandleError error code.
 		 */
-		virtual HandleError FreeHandle(Handle_t handle, IdentityToken_t *ident) =0;
+		virtual HandleError FreeHandle(Handle_t handle, IdentityToken_t *owner, IdentityToken_t *ident) =0;
 
 		/**
 		 * @brief Clones a handle by adding to its internal reference count.  Its data,

core/smn_handles.cpp

@@ -21,7 +21,10 @@ static cell_t sm_CloseHandle(IPluginContext *pContext, const cell_t *params)
 {
 	Handle_t hndl = static_cast<Handle_t>(params[1]);
 
-	HandleError err = g_HandleSys.FreeHandle(hndl, NULL);
+	/* :TODO: make this a little bit cleaner, eh? */
+	IPlugin *pPlugin = g_PluginSys.FindPluginByContext(pContext->GetContext());
+
+	HandleError err = g_HandleSys.FreeHandle(hndl, pPlugin->GetIdentity(), NULL);
   
 	if (err == HandleError_None)
 	{

core/systems/HandleSys.cpp

@@ -334,7 +334,8 @@ HandleError HandleSystem::GetHandle(Handle_t handle,
 									IdentityToken_t *ident, 
 									QHandle **in_pHandle, 
 									unsigned int *in_index,
-									HandleAccessRight access)
+									HandleAccessRight access,
+									bool ignoreFree)
 {
 	unsigned int serial = (handle >> 16);
 	unsigned int index = (handle & HANDLESYS_HANDLE_MASK);
@@ -352,7 +353,8 @@ HandleError HandleSystem::GetHandle(Handle_t handle,
 	{
 		return HandleError_Access;
 	}
-	if (!pHandle->set)
+	if (!pHandle->set
+		|| (pHandle->set == HandleSet_Freed && !ignoreFree))
 	{
 		return HandleError_Freed;
 	} else if (pHandle->set == HandleSet_Identity
@@ -383,6 +385,12 @@ HandleError HandleSystem::CloneHandle(Handle_t handle, Handle_t *out_newhandle,
 		return err;
 	}
 
+	/* Identities cannot be cloned */
+	if (pHandle->set == HandleSet_Identity)
+	{
+		return HandleError_Identity;
+	}
+
 	QHandleType *pType = &m_Types[pHandle->type];
 
 	/* Get a new Handle ID */
@@ -395,7 +403,8 @@ HandleError HandleSystem::CloneHandle(Handle_t handle, Handle_t *out_newhandle,
 		return err;
 	}
 
-	pNewHandle->clone = index;
+	pNewHandle->clone = handle;
+	pHandle->refcount++;
 
 	if (out_newhandle)
 	{
@@ -405,39 +414,58 @@ HandleError HandleSystem::CloneHandle(Handle_t handle, Handle_t *out_newhandle,
 	return HandleError_None;
 }
 
-HandleError HandleSystem::FreeHandle(Handle_t handle, IdentityToken_t *ident)
+HandleError HandleSystem::FreeHandle(Handle_t handle, IdentityToken_t *pOwner, IdentityToken_t *ident)
 {
 	unsigned int index;
 	QHandle *pHandle;
 	HandleError err;
 
-	if ((err=GetHandle(handle, ident, &pHandle, &index, HandleAccess_Delete)) != HandleError_None)
+	if ((err=GetHandle(handle, ident, &pHandle, &index, HandleAccess_IdentDelete)) != HandleError_None)
 	{
 		return err;
 	}
 
 	QHandleType *pType = &m_Types[pHandle->type];
 
+	if (pType->sec.access[HandleAccess_OwnerDelete] == false
+		&& pHandle->owner
+		&& pHandle->owner != pOwner)
+	{
+		return HandleError_Access;
+	}
+
 	bool dofree = false;
 	if (pHandle->clone)
 	{
-		/* If we're a clone, there's not a lot to do. */
-		if (FreeHandle(pHandle->clone, ident) != HandleError_None)
+		/* If we're a clone, decrease the parent reference count */
+		QHandle *pMaster;
+		unsigned int master;
+
+		/* This call should not return an error, it'd be a corruption sign */
+		err = GetHandle(pHandle->clone, ident, &pMaster, &master, HandleAccess_IdentDelete, true);
+		assert(err == HandleError_None);
+
+		/* Release the clone now */
+		ReleasePrimHandle(index);
+
+		/* Decrement the master's reference count */
+		if (--pMaster->refcount == 0)
 		{
-			assert(false);
+			/* Type should be the same but do this anyway... */
+			pType = &m_Types[pMaster->type];
+			pType->dispatch->OnHandleDestroy(pMaster->type, pMaster->object);
+			ReleasePrimHandle(master);
 		}
-		dofree = true;
 	} else {
+		/* Decrement, free if necessary */
 		if (--pHandle->refcount == 0)
 		{
-			dofree = true;
 			pType->dispatch->OnHandleDestroy(pHandle->type, pHandle->object);
-		}
-	}
-
-	if (dofree)
-	{
 			ReleasePrimHandle(index);
+		} else {
+			/* We must be cloned, so mark ourselves as freed */
+			pHandle->set = HandleSet_Freed;
+		}
 	}
 
 	return HandleError_None;
@@ -477,7 +505,8 @@ HandleError HandleSystem::ReadHandle(Handle_t handle,
 		/* if we're a clone, the rules change - object is ONLY in our reference */
 		if (pHandle->clone)
 		{
-			pHandle = &m_Handles[pHandle->clone];
+			/* :TODO: optimize this */
+			return ReadHandle(pHandle->clone, pHandle->type, ident, object);
 		}
 		*object = pHandle->object;
 	}

core/systems/HandleSys.h

@@ -36,8 +36,9 @@
 enum HandleSet
 {
 	HandleSet_None = 0,
-	HandleSet_Used,
-	HandleSet_Identity
+	HandleSet_Used,			/* The Handle is in use */
+	HandleSet_Freed,		/* The "master" Handle of a clone chain is freed */
+	HandleSet_Identity,		/* The Handle is a special identity */
 };
 
 struct QHandle
@@ -91,7 +92,7 @@ public: //IHandleSystem
 							IdentityToken_t *source, 
 							IdentityToken_t *ident);
 	Handle_t CreateScriptHandle(HandleType_t type, void *object, IPluginContext *pContext, IdentityToken_t *ident);
-	HandleError FreeHandle(Handle_t handle, IdentityToken_t *ident);
+	HandleError FreeHandle(Handle_t handle, IdentityToken_t *owner, IdentityToken_t *ident);
 	HandleError CloneHandle(Handle_t handle, Handle_t *newhandle, IdentityToken_t *source, IdentityToken_t *ident);
 	HandleError ReadHandle(Handle_t handle, HandleType_t type, IdentityToken_t *ident, void **object);
 	bool TypeCheck(HandleType_t intype, HandleType_t outtype);
@@ -103,7 +104,8 @@ protected:
 						  IdentityToken_t *ident, 
 						  QHandle **pHandle, 
 						  unsigned int *index,
-						  HandleAccessRight access);
+						  HandleAccessRight access,
+						  bool ignoreFree=false);
 
 	/**
 	 * Creates a basic handle and sets its reference count to 1.

core/systems/PluginSys.cpp

@@ -74,7 +74,7 @@ CPlugin::~CPlugin()
 
 	if (m_handle)
 	{
-		g_HandleSys.FreeHandle(m_handle, g_PluginSys.GetIdentity());
+		g_HandleSys.FreeHandle(m_handle, g_PluginSys.GetIdentity(), g_PluginSys.GetIdentity());
 		g_ShareSys.DestroyIdentity(m_ident);
 	}
 }
@@ -1117,7 +1117,7 @@ void CPluginManager::OnSourceModAllInitialized()
 
 	sec.owner = m_MyIdent;	/* :TODO: implement ShareSys */
 	sec.access[HandleAccess_Create] = false;
-	sec.access[HandleAccess_Delete] = false;
+	sec.access[HandleAccess_IdentDelete] = false;
 	sec.access[HandleAccess_Inherit] = false;
 	sec.access[HandleAccess_Clone] = false;
 	

core/systems/ShareSys.cpp

@@ -27,7 +27,7 @@ void ShareSystem::OnSourceModStartup(bool late)
 
 	sec.owner = GetIdentRoot();
 	sec.access[HandleAccess_Inherit] = false;
-	sec.access[HandleAccess_Delete] = false;
+	sec.access[HandleAccess_IdentDelete] = false;
 	
 	m_TypeRoot = g_HandleSys.CreateTypeEx("Identity", this, 0, &sec, NULL);
 	m_IfaceType = g_HandleSys.CreateTypeEx("Interface", this, 0, &sec, NULL);
@@ -184,7 +184,7 @@ void ShareSystem::AddNatives(IdentityToken_t *token, const sp_nativeinfo_t *nati
 
 void ShareSystem::DestroyIdentity(IdentityToken_t *identity)
 {
-	g_HandleSys.FreeHandle(identity->ident, GetIdentRoot());
+	g_HandleSys.FreeHandle(identity->ident, NULL, GetIdentRoot());
 	delete identity;
 }