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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
*
* 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
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*
* ***** END LICENSE BLOCK ***** */
#ifndef _MORKMAP_
#define _MORKMAP_ 1
#ifndef _MORK_
# include "mork.h"
#endif
#ifndef _MORKNODE_
# include "morkNode.h"
#endif
// 456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789
/* (These hash methods closely resemble those in public domain IronDoc.) */
/*| Equal: equal for hash table. Note equal(a,b) implies hash(a)==hash(b).
|*/
typedef mork_bool (*morkMap_mEqual)(const morkMap* self, morkEnv* ev,
const void* inKeyA, const void* inKeyB);
/*| Hash: hash for hash table. Note equal(a,b) implies hash(a)==hash(b).
|*/
typedef mork_u4 (*morkMap_mHash)(const morkMap* self, morkEnv* ev,
const void* inKey);
/*| IsNil: whether a key slot contains a "null" value denoting "no such key".
|*/
typedef mork_bool (*morkMap_mIsNil)(const morkMap* self, morkEnv* ev,
const void* inKey);
/*| Note: notify regarding a refcounting change for a key or a value.
|*/
// typedef void (* morkMap_mNote)
//(morkMap* self, morkEnv* ev, void* inKeyOrVal);
/*| morkMapForm: slots need to initialize a new dict. (This is very similar
**| to the config object for public domain IronDoc hash tables.)
|*/
class morkMapForm { // a struct of callback method pointers for morkMap
public:
// const void* mMapForm_NilKey; // externally defined 'nil' bit pattern
// void* mMapForm_NilBuf[ 8 ]; // potential place to put NilKey
// If keys are no larger than 8*sizeof(void*), NilKey can be put in NilBuf.
// Note this should be true for all Mork subclasses, and we plan usage so.
// These three methods must always be provided, so zero will cause errors:
// morkMap_mEqual mMapForm_Equal; // for comparing two keys for identity
// morkMap_mHash mMapForm_Hash; // deterministic key to hash method
// morkMap_mIsNil mMapForm_IsNil; // to query whether a key equals 'nil'
// If any of these method slots are nonzero, then morkMap will call the
// appropriate one to notify dict users when a key or value is added or cut.
// Presumably a caller wants to know this in order to perform refcounting or
// some other kind of memory management. These methods are definitely only
// called when references to keys or values are inserted or removed, and are
// never called when the actual number of references does not change (such
// as when added keys are already present or cut keys are alreading missing).
//
// morkMap_mNote mMapForm_AddKey; // if nonzero, notify about add key
// morkMap_mNote mMapForm_CutKey; // if nonzero, notify about cut key
// morkMap_mNote mMapForm_AddVal; // if nonzero, notify about add val
// morkMap_mNote mMapForm_CutVal; // if nonzero, notify about cut val
//
// These note methods have been removed because it seems difficult to
// guarantee suitable alignment of objects passed to notification methods.
// Note dict clients should pick key and val sizes that provide whatever
// alignment will be required for an array of such keys and values.
mork_size mMapForm_KeySize; // size of every key (cannot be zero)
mork_size mMapForm_ValSize; // size of every val (can indeed be zero)
mork_bool mMapForm_HoldChanges; // support changes array in the map
mork_change mMapForm_DummyChange; // change used for false HoldChanges
mork_bool mMapForm_KeyIsIP; // key is mork_ip sized
mork_bool mMapForm_ValIsIP; // key is mork_ip sized
};
/*| morkAssoc: a canonical association slot in a morkMap. A single assoc
**| instance does nothing except point to the next assoc in the same bucket
**| of a hash table. Each assoc has only two interesting attributes: 1) the
**| address of the assoc, and 2) the next assoc in a bucket's list. The assoc
**| address is interesting because in the context of an array of such assocs,
**| one can determine the index of a particular assoc in the array by address
**| arithmetic, subtracting the array address from the assoc address. And the
**| index of each assoc is the same index as the associated key and val slots
**| in the associated arrays
**|
**|| Think of an assoc instance as really also containing a key slot and a val
**| slot, where each key is mMap_Form.mMapForm_KeySize bytes in size, and
**| each val is mMap_Form.mMapForm_ValSize in size. But the key and val
**| slots are stored in separate arrays with indexes that are parallel to the
**| indexes in the array of morkAssoc instances. We have taken the variable
**| sized slots out of the morkAssoc structure, and put them into parallel
**| arrays associated with each morkAssoc by array index. And this leaves us
**| with only the link field to the next assoc in each assoc instance.
|*/
class morkAssoc {
public:
morkAssoc* mAssoc_Next;
};
#define morkDerived_kMap /*i*/ 0x4D70 /* ascii 'Mp' */
#define morkMap_kTag /*i*/ 0x6D4D6150 /* ascii 'mMaP' */
/*| morkMap: a hash table based on the public domain IronDoc hash table
**| (which is in turn rather like a similar OpenDoc hash table).
|*/
class morkMap : public morkNode {
// public: // slots inherited from morkNode (meant to inform only)
// nsIMdbHeap* mNode_Heap;
// 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
public: // state is public because the entire Mork system is private
nsIMdbHeap* mMap_Heap; // strong ref to heap allocating all space
mork_u4 mMap_Tag; // must equal morkMap_kTag
// When a morkMap instance is constructed, the dict form slots must be
// provided in order to properly configure a dict with all runtime needs:
morkMapForm mMap_Form; // construction time parameterization
// Whenever the dict changes structure in a way that would affect any
// iteration of the dict associations, the seed increments to show this:
mork_seed mMap_Seed; // counter for member and structural changes
// The current total assoc capacity of the dict is mMap_Slots, where
// mMap_Fill of these slots are actually holding content, so mMap_Fill
// is the actual membership count, and mMap_Slots is how larger membership
// can become before the hash table must grow the buffers being used.
mork_count mMap_Slots; // count of slots in the hash table
mork_fill mMap_Fill; // number of used slots in the hash table
// Key and value slots are bound to corresponding mMap_Assocs array slots.
// Instead of having a single array like this: {key,val,next}[ mMap_Slots ]
// we have instead three parallel arrays with essentially the same meaning:
// {key}[ mMap_Slots ], {val}[ mMap_Slots ], {assocs}[ mMap_Slots ]
mork_u1* mMap_Keys; // mMap_Slots * mMapForm_KeySize buffer
mork_u1* mMap_Vals; // mMap_Slots * mMapForm_ValSize buffer
// An assoc is "used" when it appears in a bucket's linked list of assocs.
// Until an assoc is used, it appears in the FreeList linked list. Every
// assoc that becomes used goes into the bucket determined by hashing the
// key associated with a new assoc. The key associated with a new assoc
// goes in to the slot in mMap_Keys which occupies exactly the same array
// index as the array index of the used assoc in the mMap_Assocs array.
morkAssoc* mMap_Assocs; // mMap_Slots * sizeof(morkAssoc) buffer
// The changes array is only needed when the
mork_change* mMap_Changes; // mMap_Slots * sizeof(mork_change) buffer
// The Buckets array need not be the same length as the Assocs array, but we
// usually do it that way so the average bucket depth is no more than one.
// (We could pick a different policy, or make it parameterizable, but that's
// tuning we can do some other time.)
morkAssoc** mMap_Buckets; // mMap_Slots * sizeof(morkAssoc*) buffer
// The length of the mMap_FreeList should equal (mMap_Slots - mMap_Fill).
// We need a free list instead of a simpler representation because assocs
// can be cut and returned to availability in any kind of unknown pattern.
// (However, when assocs are first allocated, or when the dict is grown, we
// know all new assocs are contiguous and can chain together adjacently.)
morkAssoc* mMap_FreeList; // list of unused mMap_Assocs array slots
public: // getters (morkProbeMap compatibility)
mork_fill MapFill() const { return mMap_Fill; }
// { ===== begin morkNode interface =====
public: // morkNode virtual methods
virtual void CloseMorkNode(morkEnv* ev) override; // CloseMap() only if open
virtual ~morkMap(); // assert that CloseMap() executed earlier
public: // morkMap construction & destruction
morkMap(morkEnv* ev, const morkUsage& inUsage, nsIMdbHeap* ioNodeHeap,
mork_size inKeySize, mork_size inValSize, mork_size inSlots,
nsIMdbHeap* ioSlotHeap, mork_bool inHoldChanges);
void CloseMap(morkEnv* ev); // called by
public: // dynamic type identification
mork_bool IsMap() const {
return IsNode() && mNode_Derived == morkDerived_kMap;
}
// } ===== end morkNode methods =====
public: // poly map hash table methods
// { ===== begin morkMap poly interface =====
virtual mork_bool // note: equal(a,b) implies hash(a) == hash(b)
Equal(morkEnv* ev, const void* inKeyA, const void* inKeyB) const = 0;
virtual mork_u4 // note: equal(a,b) implies hash(a) == hash(b)
Hash(morkEnv* ev, const void* inKey) const = 0;
// } ===== end morkMap poly interface =====
public: // open utility methods
mork_bool GoodMapTag() const { return mMap_Tag == morkMap_kTag; }
mork_bool GoodMap() const { return (IsNode() && GoodMapTag()); }
void NewIterOutOfSyncError(morkEnv* ev);
void NewBadMapError(morkEnv* ev);
void NewSlotsUnderflowWarning(morkEnv* ev);
void InitMap(morkEnv* ev, mork_size inSlots);
protected: // internal utility methods
friend class morkMapIter;
void clear_map(morkEnv* ev, nsIMdbHeap* ioHeap);
void* alloc(morkEnv* ev, mork_size inSize);
void* clear_alloc(morkEnv* ev, mork_size inSize);
void push_free_assoc(morkAssoc* ioAssoc) {
ioAssoc->mAssoc_Next = mMap_FreeList;
mMap_FreeList = ioAssoc;
}
morkAssoc* pop_free_assoc() {
morkAssoc* assoc = mMap_FreeList;
if (assoc) mMap_FreeList = assoc->mAssoc_Next;
return assoc;
}
morkAssoc** find(morkEnv* ev, const void* inKey, mork_u4 inHash) const;
mork_u1* new_keys(morkEnv* ev, mork_num inSlots);
mork_u1* new_values(morkEnv* ev, mork_num inSlots);
mork_change* new_changes(morkEnv* ev, mork_num inSlots);
morkAssoc** new_buckets(morkEnv* ev, mork_num inSlots);
morkAssoc* new_assocs(morkEnv* ev, mork_num inSlots);
mork_bool new_arrays(morkEnv* ev, morkHashArrays* old, mork_num inSlots);
mork_bool grow(morkEnv* ev);
void get_assoc(void* outKey, void* outVal, mork_pos inPos) const;
void put_assoc(const void* inKey, const void* inVal, mork_pos inPos) const;
public: // inlines to form slots
// const void* FormNilKey() const { return mMap_Form.mMapForm_NilKey; }
// morkMap_mEqual FormEqual() const { return mMap_Form.mMapForm_Equal; }
// morkMap_mHash FormHash() const { return mMap_Form.mMapForm_Hash; }
// orkMap_mIsNil FormIsNil() const { return mMap_Form.mMapForm_IsNil; }
// morkMap_mNote FormAddKey() const { return mMap_Form.mMapForm_AddKey; }
// morkMap_mNote FormCutKey() const { return mMap_Form.mMapForm_CutKey; }
// morkMap_mNote FormAddVal() const { return mMap_Form.mMapForm_AddVal; }
// morkMap_mNote FormCutVal() const { return mMap_Form.mMapForm_CutVal; }
mork_size FormKeySize() const { return mMap_Form.mMapForm_KeySize; }
mork_size FormValSize() const { return mMap_Form.mMapForm_ValSize; }
mork_bool FormKeyIsIP() const { return mMap_Form.mMapForm_KeyIsIP; }
mork_bool FormValIsIP() const { return mMap_Form.mMapForm_ValIsIP; }
mork_bool FormHoldChanges() const { return mMap_Form.mMapForm_HoldChanges; }
mork_change* FormDummyChange() { return &mMap_Form.mMapForm_DummyChange; }
public: // other map methods
mork_bool Put(morkEnv* ev, const void* inKey, const void* inVal, void* outKey,
void* outVal, mork_change** outChange);
mork_bool Cut(morkEnv* ev, const void* inKey, void* outKey, void* outVal,
mork_change** outChange);
mork_bool Get(morkEnv* ev, const void* inKey, void* outKey, void* outVal,
mork_change** outChange);
mork_num CutAll(morkEnv* ev);
private: // copying is not allowed
morkMap(const morkMap& other);
morkMap& operator=(const morkMap& other);
public: // typesafe refcounting inlines calling inherited morkNode methods
static void SlotWeakMap(morkMap* me, morkEnv* ev, morkMap** ioSlot) {
morkNode::SlotWeakNode((morkNode*)me, ev, (morkNode**)ioSlot);
}
static void SlotStrongMap(morkMap* me, morkEnv* ev, morkMap** ioSlot) {
morkNode::SlotStrongNode((morkNode*)me, ev, (morkNode**)ioSlot);
}
};
/*| morkMapIter: an iterator for morkMap and subclasses. This is not a node,
**| and expected usage is as a member of some other node subclass, such as in
**| a cursor subclass or a thumb subclass. Also, iters might be as temp stack
**| objects when scanning the content of a map.
|*/
class morkMapIter { // iterator for hash table map
protected:
morkMap* mMapIter_Map; // map to iterate, NOT refcounted
mork_seed mMapIter_Seed; // cached copy of map's seed
morkAssoc** mMapIter_Bucket; // one bucket in mMap_Buckets array
morkAssoc** mMapIter_AssocRef; // usually *AtRef equals Here
morkAssoc* mMapIter_Assoc; // the current assoc in an iteration
morkAssoc* mMapIter_Next; // mMapIter_Assoc->mAssoc_Next */
public:
morkMapIter(morkEnv* ev, morkMap* ioMap);
void CloseMapIter(morkEnv* ev);
morkMapIter(); // everything set to zero -- need to call InitMapIter()
protected: // we want all subclasses to provide typesafe wrappers:
void InitMapIter(morkEnv* ev, morkMap* ioMap);
// The morkAssoc returned below is always either mork_change* or
// else nil (when there is no such assoc). We return a pointer to
// the change rather than a simple bool, because callers might
// want to access change info associated with an assoc.
mork_change* First(morkEnv* ev, void* outKey, void* outVal);
mork_change* Next(morkEnv* ev, void* outKey, void* outVal);
mork_change* Here(morkEnv* ev, void* outKey, void* outVal);
mork_change* CutHere(morkEnv* ev, void* outKey, void* outVal);
};
// 456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789
#endif /* _MORKMAP_ */