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Diffstat (limited to 'db/mork/src/morkMap.h')
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diff --git a/db/mork/src/morkMap.h b/db/mork/src/morkMap.h new file mode 100644 index 000000000..57104df0e --- /dev/null +++ b/db/mork/src/morkMap.h @@ -0,0 +1,394 @@ +/* -*- 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 _MORKMAP_ +#define _MORKMAP_ 1 + +#ifndef _MORK_ +#include "mork.h" +#endif + +#ifndef _MORKNODE_ +#include "morkNode.h" +#endif + +//3456789_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 utitity 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 utitity 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); +}; + +//3456789_123456789_123456789_123456789_123456789_123456789_123456789_123456789 + +#endif /* _MORKMAP_ */ |