Make classbase and refcountbase uncopyable; expand comments on their indended uses

git-svn-id: http://svn.inspircd.org/repository/trunk/inspircd@11888 e03df62e-2008-0410-955e-edbf42e46eb7

9 files changed, 48 insertions, 25 deletions

diff --git a/include/base.h b/include/base.h
index ed03eeac5..624e2174f 100644
--- a/include/base.h
+++ b/include/base.h
@@ -18,11 +18,17 @@
 #include <deque>
 #include <string>
 
-/** The base class for all inspircd classes.
- * Wherever possible, all classes you create should inherit from this,
- * giving them the ability to be passed to various core functions
- * as 'anonymous' classes.
-*/
+/** Dummy class to help enforce culls being parent-called up to classbase */
+class CullResult
+{
+	CullResult();
+	friend class classbase;
+};
+
+/** The base class for all inspircd classes with a well-defined lifetime.
+ * Classes that inherit from this may be destroyed through GlobalCulls,
+ * and may rely on cull() being called prior to their deletion.
+ */
 class CoreExport classbase
 {
  public:
@@ -33,23 +39,39 @@ class CoreExport classbase
 	 *
 	 * @return true to allow the delete, or false to halt the delete
 	 */
-	virtual bool cull();
+	virtual CullResult cull();
 	virtual ~classbase();
+ private:
+	// uncopyable
+	classbase(const classbase&);
+	void operator=(const classbase&);
 };
 
 /** The base class for inspircd classes that support reference counting.
  * Any objects that do not have a well-defined lifetime should inherit from
- * this
+ * this, and should be assigned to a reference<type> object to establish their
+ * lifetime.
+ *
+ * Reference objects should not hold circular references back to themselves,
+ * even indirectly; this will cause a memory leak because the count will never
+ * drop to zero.
+ *
+ * Using a normal pointer for the object is recommended if you can assure that
+ * at least one reference<> will remain as long as that pointer is used; this
+ * will avoid the slight overhead of changing the reference count.
  */
-class CoreExport refcountbase : public classbase
+class CoreExport refcountbase
 {
 	unsigned int refcount;
  public:
 	refcountbase();
-	virtual bool cull();
 	virtual ~refcountbase();
 	inline unsigned int GetReferenceCount() const { return refcount; }
 	friend class reference_base;
+ private:
+	// uncopyable
+	refcountbase(const refcountbase&);
+	void operator=(const refcountbase&);
 };
 
 class CoreExport reference_base
@@ -81,7 +103,7 @@ class reference : public reference_base
 		if (value)
 		{
 			int rc = dec(value);
-			if (rc == 0 && value->cull())
+			if (rc == 0)
 				delete value;
 		}
 	}
diff --git a/include/channels.h b/include/channels.h
index 1ded25a73..7728bb55b 100644
--- a/include/channels.h
+++ b/include/channels.h
@@ -36,7 +36,7 @@ struct ModResult;
 /** Holds an entry for a ban list, exemption list, or invite list.
  * This class contains a single element in a channel list, such as a banlist.
  */
-class HostItem : public classbase
+class HostItem
 {
  public:
 	/** Time the item was added
diff --git a/include/dns.h b/include/dns.h
index 76a69b6e4..1b9ce59a4 100644
--- a/include/dns.h
+++ b/include/dns.h
@@ -40,7 +40,7 @@ class Module;
 /**
  * Result status, used internally
  */
-class CoreExport DNSResult : public classbase
+class CoreExport DNSResult
 {
  public:
 	/** Result ID
@@ -72,7 +72,7 @@ typedef std::pair<unsigned char*, std::string> DNSInfo;
 
 /** Cached item stored in the query cache.
  */
-class CoreExport CachedQuery : public classbase
+class CoreExport CachedQuery
 {
  public:
 	/** The cached result data, an IP or hostname
@@ -181,7 +181,7 @@ enum ForceProtocol
  * can occur by calling virtual methods, one is a success situation, and the other
  * an error situation.
  */
-class CoreExport Resolver : public Extensible
+class CoreExport Resolver
 {
  protected:
 	/**
diff --git a/include/extensible.h b/include/extensible.h
index ff7bce477..ca9c44546 100644
--- a/include/extensible.h
+++ b/include/extensible.h
@@ -72,6 +72,7 @@ class CoreExport Extensible : public classbase
 	 */
 	inline const ExtensibleStore& GetExtList() const { return extensions; }
 
+	virtual CullResult cull();
 	virtual ~Extensible();
 	void doUnhookExtensions(const std::vector<ExtensionItem*>& toRemove);
 };
diff --git a/include/hashcomp.h b/include/hashcomp.h
index 6cbc14850..5392c6ae5 100644
--- a/include/hashcomp.h
+++ b/include/hashcomp.h
@@ -204,7 +204,7 @@ namespace irc
 	 * std::string, or a const char* const* array, using overloaded
 	 * constructors.
 	 */
-	class CoreExport stringjoiner : public classbase
+	class CoreExport stringjoiner
 	{
 	 private:
 
@@ -248,7 +248,7 @@ namespace irc
 	 * It can then reproduce this list, clamped to a maximum of MAXMODES
 	 * values per line.
 	 */
-	class CoreExport modestacker : public classbase
+	class CoreExport modestacker
 	{
 	 private:
 		/** The mode sequence and its parameters
@@ -335,7 +335,7 @@ namespace irc
 	 * list will be ":item". This is to allow for parsing 'source' fields
 	 * from data.
 	 */
-	class CoreExport tokenstream : public classbase
+	class CoreExport tokenstream
 	{
 	 private:
 
@@ -394,7 +394,7 @@ namespace irc
 	 * the next token, until none remain, at which point the method returns
 	 * an empty string.
 	 */
-	class CoreExport sepstream : public classbase
+	class CoreExport sepstream
 	{
 	 private:
 		/** Original string.
@@ -467,7 +467,7 @@ namespace irc
 	 * start or end < 0) then GetToken() will return the first element
 	 * of the pair of numbers.
 	 */
-	class CoreExport portparser : public classbase
+	class CoreExport portparser
 	{
 	 private:
 
diff --git a/include/inspsocket.h b/include/inspsocket.h
index 84716eae6..3e5c75235 100644
--- a/include/inspsocket.h
+++ b/include/inspsocket.h
@@ -146,7 +146,7 @@ class CoreExport StreamSocket : public EventHandler
 	 */
 	virtual void Close();
 	/** This ensures that close is called prior to destructor */
-	virtual bool cull();
+	virtual CullResult cull();
 };
 /**
  * BufferedSocket is an extendable socket class which modules
diff --git a/include/mode.h b/include/mode.h
index 81858a823..b63e5e6a9 100644
--- a/include/mode.h
+++ b/include/mode.h
@@ -172,7 +172,7 @@ class CoreExport ModeHandler : public classbase
 	 * @param type Type of the mode (MODETYPE_USER or MODETYPE_CHANNEL)
 	 */
 	ModeHandler(Module* me, const std::string& name, char modeletter, ParamSpec params, ModeType type);
-	virtual bool cull();
+	virtual CullResult cull();
 	virtual ~ModeHandler();
 	/**
 	 * Returns true if the mode is a list mode
diff --git a/include/modules.h b/include/modules.h
index ef6f5c251..96506f598 100644
--- a/include/modules.h
+++ b/include/modules.h
@@ -230,7 +230,7 @@ do { \
  * error when attempting to load a module compiled against a different API_VERSION.
  */
 template<int api>
-class CoreExport VersionBase : public classbase
+class CoreExport VersionBase
 {
  public:
 	/** Module description
@@ -349,7 +349,7 @@ class ConfigReader;
  *  its methods will be called when irc server events occur. class inherited from module must be
  *  instantiated by the ModuleFactory class (see relevent section) for the module to be initialised.
  */
-class CoreExport Module : public Extensible
+class CoreExport Module : public classbase
 {
  public:
 	/** File that this module was loaded from
@@ -369,7 +369,7 @@ class CoreExport Module : public Extensible
 	/** Clean up prior to destruction
 	 * If you override, you must call this AFTER your module's cleanup
 	 */
-	virtual bool cull();
+	virtual CullResult cull();
 
 	/** Default destructor.
 	 * destroys a module class
diff --git a/include/users.h b/include/users.h
index ed672450e..0ce9f59ab 100644
--- a/include/users.h
+++ b/include/users.h
@@ -848,7 +848,7 @@ class CoreExport User : public StreamSocket
 	/** Default destructor
 	 */
 	virtual ~User();
-	virtual bool cull();
+	virtual CullResult cull();
 };
 
 /** Derived from Resolver, and performs user forward/reverse lookups.