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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1999
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+
+#ifndef _MORKNODE_
+#define _MORKNODE_ 1
+
+#ifndef _MORK_
+#include "mork.h"
+#endif
+
+//3456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789
+
+#define morkUsage_kHeap 'h'
+#define morkUsage_kStack 's'
+#define morkUsage_kMember 'm'
+#define morkUsage_kGlobal 'g'
+#define morkUsage_kPool 'p'
+#define morkUsage_kNone 'n'
+
+class morkUsage {
+public:
+ mork_usage mUsage_Code; // kHeap, kStack, kMember, or kGhost
+
+public:
+ morkUsage(mork_usage inCode);
+
+ morkUsage(); // does nothing except maybe call EnsureReadyStaticUsage()
+ void InitUsage( mork_usage inCode)
+ { mUsage_Code = inCode; }
+
+ ~morkUsage() { }
+ mork_usage Code() const { return mUsage_Code; }
+
+ static void EnsureReadyStaticUsage();
+
+public:
+ static const morkUsage& kHeap; // morkUsage_kHeap
+ static const morkUsage& kStack; // morkUsage_kStack
+ static const morkUsage& kMember; // morkUsage_kMember
+ static const morkUsage& kGlobal; // morkUsage_kGlobal
+ static const morkUsage& kPool; // morkUsage_kPool
+ static const morkUsage& kNone; // morkUsage_kNone
+
+ static const morkUsage& GetHeap(); // kHeap, safe at static init time
+ static const morkUsage& GetStack(); // kStack, safe at static init time
+ static const morkUsage& GetMember(); // kMember, safe at static init time
+ static const morkUsage& GetGlobal(); // kGlobal, safe at static init time
+ static const morkUsage& GetPool(); // kPool, safe at static init time
+ static const morkUsage& GetNone(); // kNone, safe at static init time
+
+};
+
+//3456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789
+
+#define morkNode_kMaxRefCount 0x0FFFF /* count sticks if it hits this */
+
+#define morkBase_kNode /*i*/ 0x4E64 /* ascii 'Nd' */
+
+/*| morkNode: several groups of two-byte integers that track the basic
+**| status of an object that can be used to compose in-memory graphs.
+**| This is the base class for nsIMdbObject (which adds members that fit
+**| the needs of an nsIMdbObject subclass). The morkNode class is also used
+**| as the base class for other Mork db classes with no strong relation to
+**| the MDB class hierarchy.
+**|
+**|| Heap: the heap in which this node was allocated, when the usage equals
+**| morkUsage_kHeap to show dynamic allocation. Note this heap is NOT ref-
+**| counted, because that would be too great and complex a burden for all
+**| the nodes allocated in that heap. So heap users should take care to
+**| understand that nodes allocated in that heap are considered protected
+**| by some inclusive context in which all those nodes are allocated, and
+**| that context must maintain at least one strong refcount for the heap.
+**| Occasionally a node subclass will indeed wish to hold a refcounted
+**| reference to a heap, and possibly the same heap that is in mNode_Heap,
+**| but this is always done in a separate slot that explicitly refcounts,
+**| so we avoid confusing what is meant by the mNode_Heap slot.
+|*/
+class morkNode /*: public nsISupports */ { // base class for constructing Mork object graphs
+
+public: // state is public because the entire Mork system is private
+
+// NS_DECL_ISUPPORTS;
+ nsIMdbHeap* mNode_Heap; // NON-refcounted heap pointer
+
+ mork_base mNode_Base; // must equal morkBase_kNode
+ mork_derived mNode_Derived; // depends on specific node subclass
+
+ mork_access mNode_Access; // kOpen, kClosing, kShut, or kDead
+ mork_usage mNode_Usage; // kHeap, kStack, kMember, kGlobal, kNone
+ mork_able mNode_Mutable; // can this node be modified?
+ mork_load mNode_Load; // is this node clean or dirty?
+
+ mork_uses mNode_Uses; // refcount for strong refs
+ mork_refs mNode_Refs; // refcount for strong refs + weak refs
+
+protected: // special case empty construction for morkHandleFrame
+ friend class morkHandleFrame;
+ morkNode() { }
+
+public: // inlines for weird mNode_Mutable and mNode_Load constants
+
+ void SetFrozen() { mNode_Mutable = morkAble_kDisabled; }
+ void SetMutable() { mNode_Mutable = morkAble_kEnabled; }
+ void SetAsleep() { mNode_Mutable = morkAble_kAsleep; }
+
+ mork_bool IsFrozen() const { return mNode_Mutable == morkAble_kDisabled; }
+ mork_bool IsMutable() const { return mNode_Mutable == morkAble_kEnabled; }
+ mork_bool IsAsleep() const { return mNode_Mutable == morkAble_kAsleep; }
+
+ void SetNodeClean() { mNode_Load = morkLoad_kClean; }
+ void SetNodeDirty() { mNode_Load = morkLoad_kDirty; }
+
+ mork_bool IsNodeClean() const { return mNode_Load == morkLoad_kClean; }
+ mork_bool IsNodeDirty() const { return mNode_Load == morkLoad_kDirty; }
+
+public: // morkNode memory management methods
+ static void* MakeNew(size_t inSize, nsIMdbHeap& ioHeap, morkEnv* ev);
+
+ void ZapOld(morkEnv* ev, nsIMdbHeap* ioHeap); // replaces operator delete()
+ // this->morkNode::~morkNode(); // first call polymorphic destructor
+ // if ( ioHeap ) // was this node heap allocated?
+ // ioHeap->Free(ev->AsMdbEnv(), this);
+
+public: // morkNode memory management operators
+ void* operator new(size_t inSize, nsIMdbHeap& ioHeap, morkEnv* ev) CPP_THROW_NEW
+ { return morkNode::MakeNew(inSize, ioHeap, ev); }
+
+
+protected: // construction without an anv needed for first env constructed:
+ morkNode(const morkUsage& inUsage, nsIMdbHeap* ioHeap);
+
+ morkNode(mork_usage inCode); // usage == inCode, heap == nil
+
+// { ===== begin basic node interface =====
+public: // morkNode virtual methods
+ // virtual FlushMorkNode(morkEnv* ev, morkStream* ioStream);
+ // virtual WriteMorkNode(morkEnv* ev, morkStream* ioStream);
+
+ virtual ~morkNode(); // assert that CloseNode() executed earlier
+ virtual void CloseMorkNode(morkEnv* ev); // CloseNode() only if open
+
+ // CloseMorkNode() is the polymorphic close method called when uses==0,
+ // which must do NOTHING at all when IsOpenNode() is not true. Otherwise,
+ // CloseMorkNode() should call a static close method specific to an object.
+ // Each such static close method should either call inherited static close
+ // methods, or else perform the consolidated effect of calling them, where
+ // subclasses should closely track any changes in base classes with care.
+
+public: // morkNode construction
+ morkNode(morkEnv* ev, const morkUsage& inUsage, nsIMdbHeap* ioHeap);
+ void CloseNode(morkEnv* ev); // called by CloseMorkNode();
+ nsresult CloseMdbObject(morkEnv *ev);
+ NS_IMETHOD CloseMdbObject(nsIMdbEnv *ev);
+private: // copying is not allowed
+ morkNode(const morkNode& other);
+ morkNode& operator=(const morkNode& other);
+
+public: // dynamic type identification
+ mork_bool IsNode() const
+ { return mNode_Base == morkBase_kNode; }
+// } ===== end basic node methods =====
+
+public: // public error & warning methods
+
+ void RefsUnderUsesWarning(morkEnv* ev) const; // call if mNode_Refs < mNode_Uses
+ void NonNodeError(morkEnv* ev) const; // call when IsNode() is false
+ void NilHeapError(morkEnv* ev) const; // zero mNode_Heap when usage is kHeap
+ void NonOpenNodeError(morkEnv* ev) const; // call when IsOpenNode() is false
+
+ void NonMutableNodeError(morkEnv* ev) const; // when IsMutable() is false
+
+ void RefsOverflowWarning(morkEnv* ev) const; // call on mNode_Refs overflow
+ void UsesOverflowWarning(morkEnv* ev) const; // call on mNode_Uses overflow
+ void RefsUnderflowWarning(morkEnv* ev) const; // call on mNode_Refs underflow
+ void UsesUnderflowWarning(morkEnv* ev) const; // call on mNode_Uses underflow
+
+private: // private refcounting methods
+ mork_bool cut_use_count(morkEnv* ev); // just one part of CutStrongRef()
+
+public: // other morkNode methods
+
+ mork_bool GoodRefs() const { return mNode_Refs >= mNode_Uses; }
+ mork_bool BadRefs() const { return mNode_Refs < mNode_Uses; }
+
+ mork_uses StrongRefsOnly() const { return mNode_Uses; }
+ mork_refs WeakRefsOnly() const { return (mork_refs) ( mNode_Refs - mNode_Uses ); }
+
+ // (this refcounting derives from public domain IronDoc node refcounts)
+ virtual mork_uses AddStrongRef(morkEnv* ev);
+ virtual mork_uses CutStrongRef(morkEnv* ev);
+ mork_refs AddWeakRef(morkEnv* ev);
+ mork_refs CutWeakRef(morkEnv* ev);
+
+ const char* GetNodeAccessAsString() const; // e.g. "open", "shut", etc.
+ const char* GetNodeUsageAsString() const; // e.g. "heap", "stack", etc.
+
+ mork_usage NodeUsage() const { return mNode_Usage; }
+
+ mork_bool IsHeapNode() const
+ { return mNode_Usage == morkUsage_kHeap; }
+
+ mork_bool IsOpenNode() const
+ { return mNode_Access == morkAccess_kOpen; }
+
+ mork_bool IsShutNode() const
+ { return mNode_Access == morkAccess_kShut; }
+
+ mork_bool IsDeadNode() const
+ { return mNode_Access == morkAccess_kDead; }
+
+ mork_bool IsClosingNode() const
+ { return mNode_Access == morkAccess_kClosing; }
+
+ mork_bool IsOpenOrClosingNode() const
+ { return IsOpenNode() || IsClosingNode(); }
+
+ mork_bool HasNodeAccess() const
+ { return ( IsOpenNode() || IsShutNode() || IsClosingNode() ); }
+
+ void MarkShut() { mNode_Access = morkAccess_kShut; }
+ void MarkClosing() { mNode_Access = morkAccess_kClosing; }
+ void MarkDead() { mNode_Access = morkAccess_kDead; }
+
+public: // refcounting for typesafe subclass inline methods
+ static void SlotWeakNode(morkNode* me, morkEnv* ev, morkNode** ioSlot);
+ // If *ioSlot is non-nil, that node is released by CutWeakRef() and
+ // then zeroed out. Then if me is non-nil, this is acquired by
+ // calling AddWeakRef(), and if positive is returned to show success,
+ // then this is put into slot *ioSlot. Note me can be nil, so we
+ // permit expression '((morkNode*) 0L)->SlotWeakNode(ev, &slot)'.
+
+ static void SlotStrongNode(morkNode* me, morkEnv* ev, morkNode** ioSlot);
+ // If *ioSlot is non-nil, that node is released by CutStrongRef() and
+ // then zeroed out. Then if me is non-nil, this is acquired by
+ // calling AddStrongRef(), and if positive is returned to show success,
+ // then me is put into slot *ioSlot. Note me can be nil, so we take
+ // expression 'morkNode::SlotStrongNode((morkNode*) 0, ev, &slot)'.
+};
+
+extern void // utility method very similar to morkNode::SlotStrongNode():
+nsIMdbHeap_SlotStrongHeap(nsIMdbHeap* self, morkEnv* ev, nsIMdbHeap** ioSlot);
+ // If *ioSlot is non-nil, that heap is released by CutStrongRef() and
+ // then zeroed out. Then if self is non-nil, this is acquired by
+ // calling AddStrongRef(), and if the return value shows success,
+ // then self is put into slot *ioSlot. Note self can be nil, so we take
+ // expression 'nsIMdbHeap_SlotStrongHeap(0, ev, &slot)'.
+
+extern void // utility method very similar to morkNode::SlotStrongNode():
+nsIMdbFile_SlotStrongFile(nsIMdbFile* self, morkEnv* ev, nsIMdbFile** ioSlot);
+ // If *ioSlot is non-nil, that file is released by CutStrongRef() and
+ // then zeroed out. Then if self is non-nil, this is acquired by
+ // calling AddStrongRef(), and if the return value shows success,
+ // then self is put into slot *ioSlot. Note self can be nil, so we take
+ // expression 'nsIMdbFile_SlotStrongFile(0, ev, &slot)'.
+
+//3456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789
+
+#endif /* _MORKNODE_ */