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windows-nt/Source/XPSP1/NT/inetsrv/iis/lkrhash/inc/lkrhash.h

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/*++
Copyright (c) 1998-2001 Microsoft Corporation
Module Name :
LKRhash.h
Abstract:
Declares LKRhash: a fast, scalable, cache- and MP-friendly hash table
Author:
Paul (Per-Ake) Larson, PALarson@microsoft.com, July 1997
Murali R. Krishnan (MuraliK)
George V. Reilly (GeorgeRe) 06-Jan-1998
Environment:
Win32 - User Mode
Project:
Internet Information Server RunTime Library
Revision History:
10/01/1998 - Change name from LKhash to LKRhash
10/2000 - Port to kernel mode
--*/
#ifndef __LKRHASH_H__
#define __LKRHASH_H__
#ifndef __LKR_HASH_H__
// external definitions
# include <LKR-hash.h>
#endif // !__LKR_HASH_H__
#ifndef __IRTLDBG_H__
# include <IrtlDbg.h>
#endif // !__IRTLDBG_H__
#ifndef LKR_NO_GLOBAL_LIST
# ifndef __LSTENTRY_H__
# include <LstEntry.h>
# endif // !__LSTENTRY_H__
#else // LKR_NO_GLOBAL_LIST
# ifndef __LOCKS_H__
# include <Locks.h>
# endif // !__LOCKS_H__
#endif // LKR_NO_GLOBAL_LIST
#ifndef __HASHFN_H__
# include <HashFn.h>
#endif // !__HASHFN_H__
// Disable old-style deprecated iterators, by default
#ifndef LKR_DEPRECATED_ITERATORS
# define LKR_NO_DEPRECATED_ITERATORS
#endif // !LKR_DEPRECATED_ITERATORS
#ifndef LKR_NO_DEPRECATED_ITERATORS
# undef LKR_DEPRECATED_ITERATORS
# define LKR_DEPRECATED_ITERATORS 1
#endif // !LKR_NO_DEPRECATED_ITERATORS
#undef LKR_COUNTDOWN
// #define __LKRHASH_NO_NAMESPACE__
// #define __HASHFN_NO_NAMESPACE__
// #define LKR_TABLE_LOCK CReaderWriterLock3
// #define LKR_BUCKET_LOCK CSmallSpinLock
#ifndef LKR_TABLE_LOCK
# if defined(LKR_EXPOSED_TABLE_LOCK) || defined(LKR_DEPRECATED_ITERATORS)
// need recursive writelocks
# define LKR_TABLE_LOCK CReaderWriterLock3
# else
// use non-recursive writelocks
# define LKR_TABLE_LOCK CReaderWriterLock2
# endif
#endif // !LKR_TABLE_LOCK
#ifndef LKR_BUCKET_LOCK
# ifdef LKR_DEPRECATED_ITERATORS
# define LKR_BUCKET_LOCK CReaderWriterLock3
# else // !LKR_DEPRECATED_ITERATORS
# define LKR_BUCKET_LOCK CSmallSpinLock
# endif // !LKR_DEPRECATED_ITERATORS
#endif // !LKR_BUCKET_LOCK
//=====================================================================
// The class CLKRLinearHashTable defined in this file provides dynamic hash
// tables, i.e. tables that grow and shrink dynamically with
// the number of records in the table.
// The basic method used is linear hashing, as explained in:
//
// P.-A. Larson, Dynamic Hash Tables, Comm. of the ACM, 31, 4 (1988)
//
// This version has the following characteristics:
// - It is thread-safe and uses spin locks for synchronization.
// - It was designed to support very high rates of concurrent
// operations (inserts/deletes/lookups). It achieves this by
// (a) partitioning a CLKRHashTable into a collection of
// CLKRLinearHashTables to reduce contention on the global table lock.
// (b) minimizing the hold time on a table lock, preferring to lock
// down a bucket chain instead.
// - The design is L1 cache-conscious. See CNodeClump.
// - It is designed for sets varying in size from a dozen
// elements to several million.
//
// Main classes:
// CLKRLinearHashTable: thread-safe linear hash table
// CLKRHashTable: collection of CLKRLinearHashTables
// CTypedHashTable: typesafe wrapper for CLKRHashTable
//
//
// Paul Larson, palarson@microsoft.com, July 1997
// Original implementation with input from Murali R. Krishnan,
// muralik@microsoft.com.
//
// George V. Reilly, georgere@microsoft.com, Dec 1997-Jan 1998
// Massive cleanup and rewrite. Added templates.
//=====================================================================
// 1) Linear Hashing
// ------------------
//
// Linear hash tables grow and shrink dynamically with the number of
// records in the table. The growth or shrinkage is smooth: logically,
// one bucket at a time but physically in larger increments
// (64 buckets). An insertion (deletion) may cause an expansion
// (contraction) of the table. This causes relocation of a small number
// of records (at most one bucket worth). All operations (insert,
// delete, lookup) take constant expected time, regardless of the
// current size or the growth of the table.
//
// 2) LKR extensions to Linear hash table
// --------------------------------------
//
// Larson-Krishnan-Reilly extensions to Linear hash tables for multiprocessor
// scalability and improved cache performance.
//
// Traditional implementations of linear hash tables use one global lock
// to prevent interference between concurrent operations
// (insert/delete/lookup) on the table. The single lock easily becomes
// the bottleneck in SMP scenarios when multiple threads are used.
//
// Traditionally, a (hash) bucket is implemented as a chain of
// single-item nodes. Every operation results in chasing down a chain
// looking for an item. However, pointer chasing is very slow on modern
// systems because almost every jump results in a cache miss. L2 (or L3)
// cache misses are very expensive in missed CPU cycles and the cost is
// increasing (going to 100s of cycles in the future).
//
// LKR extensions offer
// 1) Partitioning (by hashing) of records among multiple subtables.
// Each subtable has locks but there is no global lock. Each
// subtable receives a much lower rate of operations, resulting in
// fewer conflicts.
//
// 2) Improved cache locality by grouping keys and their hash values
// into contigous chunks that fit exactly into one (or a few)
// cache lines.
//
// Specifically the implementation that exists here achieves this using
// the following techniques.
//
// Class CLKRHashTable is the top-level data structure that dynamically
// creates m_cSubTables linear hash tables. The CLKRLinearHashTables act as
// the subtables to which items and accesses are fanned out. A good
// hash function multiplexes requests uniformly to various subtables,
// thus minimizing traffic to any single subtable. The implemenation
// uses a home-grown version of bounded spinlocks, that is, a thread
// does not spin on a lock indefinitely, instead yielding after a
// predetermined number of loops.
//
// Each CLKRLinearHashTable consists of a CDirEntry pointing to segments
// each holding m_dwSegSize CBuckets. Each CBucket in turn consists of a
// chain of CNodeClumps. Each CNodeClump contains a group of
// NODES_PER_CLUMP hash values (aka hash keys or signatures) and
// pointers to the associated data items. Keeping the signatures
// together increases the cache locality in scans for lookup.
//
// Traditionally, people store a link-list element right inside the
// object that is hashed and use this link-list for the chaining of data
// blocks. However, keeping just the pointers to the data object and
// not chaining through them limits the need for bringing in the data
// object to the cache. We need to access the data object only if the
// hash values match. This limits the cache-thrashing behaviour
// exhibited by conventional implementations. It has the additional
// benefit that the objects themselves do not need to be modified
// in order to be collected in the hash table (i.e., it's non-invasive).
#ifdef LKR_STL_ITERATORS
// needed for std::forward_iterator_tag, etc
# include <utility>
// The iterators have very verbose tracing. Don't want it on all the time
// in debug builds.
# if defined(IRTLDEBUG) && (LKR_STL_ITERATORS >= 2)
# define LKR_ITER_TRACE IrtlTrace
# else // !defined(IRTLDEBUG) || LKR_STL_ITERATORS < 2
# define LKR_ITER_TRACE 1 ? (void)0 : IrtlTrace
# endif // !defined(IRTLDEBUG) || LKR_STL_ITERATORS < 2
#endif // LKR_STL_ITERATORS
//--------------------------------------------------------------------
// Default values for the hashtable constructors
enum {
#ifdef _WIN64
LK_DFLT_MAXLOAD= 4, // 64-byte nodes => NODES_PER_CLUMP = 4
#else
LK_DFLT_MAXLOAD= 7, // Default upperbound on average chain length.
#endif
LK_DFLT_INITSIZE=LK_MEDIUM_TABLESIZE, // Default initial size of hash table
LK_DFLT_NUM_SUBTBLS= 0, // Use a heuristic to choose #subtables
};
/*--------------------------------------------------------------------
* Undocumented additional creation flag parameters to LKR_CreateTable
*/
enum {
LK_CREATE_NON_PAGED_ALLOCS = 0x1000, // Use paged or NP pool in kernel
};
//--------------------------------------------------------------------
// Custom memory allocators (optional)
//--------------------------------------------------------------------
#if !defined(LKR_NO_ALLOCATORS) && !defined(LKRHASH_KERNEL_MODE)
// # define LKRHASH_ACACHE 1
// # define LKRHASH_ROCKALL_FAST 1
#endif // !LKR_NO_ALLOCATORS && !LKRHASH_KERNEL_MODE
#if defined(LKRHASH_ACACHE)
# include <acache.hxx>
class ACache : public ALLOC_CACHE_HANDLER
{
private:
SIZE_T m_cb;
public:
ACache(IN LPCSTR pszName, IN const ALLOC_CACHE_CONFIGURATION* pacConfig)
: ALLOC_CACHE_HANDLER(pszName, pacConfig),
m_cb(m_acConfig.cbSize)
{}
SIZE_T ByteSize() const
{
return m_cb;
}
static const TCHAR* ClassName() {return _TEXT("ACache");}
}; // class ACache
typedef ACache CLKRhashAllocator;
# define LKRHASH_ALLOCATOR_NEW(C, N, Tag) \
const ALLOC_CACHE_CONFIGURATION acc = { 1, N, sizeof(C) }; \
C::sm_palloc = new ACache("LKRhash:" #C, &acc);
#elif defined(LKRHASH_ROCKALL_FAST)
# include <FastHeap.hpp>
class FastHeap : public FAST_HEAP
{
private:
SIZE_T m_cb;
public:
FastHeap(SIZE_T cb)
: m_cb(cb)
{}
LPVOID Alloc()
{ return New(m_cb, NULL, false); }
BOOL Free(LPVOID pvMem)
{ return Delete(pvMem); }
SIZE_T ByteSize() const
{
return m_cb;
}
static const TCHAR* ClassName() {return _TEXT("FastHeap");}
}; // class FastHeap
typedef FastHeap CLKRhashAllocator;
# define LKRHASH_ALLOCATOR_NEW(C, N, Tag) \
C::sm_palloc = new FastHeap(sizeof(C))
#endif // LKRHASH_ROCKALL_FAST
#ifdef LKRHASH_ALLOCATOR_NEW
// placed inline in the declaration of class C
# define LKRHASH_ALLOCATOR_DEFINITIONS(C) \
protected: \
friend class CLKRLinearHashTable; \
friend BOOL LKR_Initialize(); \
friend void LKR_Terminate(); \
public: \
static CLKRhashAllocator* sm_palloc; \
static void* operator new(size_t s) \
{ \
IRTLASSERT(s == sizeof(C)); \
IRTLASSERT(sm_palloc != NULL); \
return sm_palloc->Alloc(); \
} \
static void operator delete(void* pv) \
{ \
IRTLASSERT(pv != NULL); \
IRTLASSERT(sm_palloc != NULL); \
sm_palloc->Free(pv); \
}
// used in LKRHashTableInit()
# define LKRHASH_ALLOCATOR_INIT(C, N, Tag, f) \
{ \
if (f) \
{ \
IRTLASSERT(C::sm_palloc == NULL); \
LKRHASH_ALLOCATOR_NEW(C, N, Tag); \
f = (C::sm_palloc != NULL); \
} \
}
// used in LKRHashTableUninit()
# define LKRHASH_ALLOCATOR_UNINIT(C) \
{ \
if (C::sm_palloc != NULL) \
{ \
delete C::sm_palloc; \
C::sm_palloc = NULL; \
} \
}
#else // !LKRHASH_ALLOCATOR_NEW
# define LKRHASH_ALLOCATOR_DEFINITIONS(C)
# define LKRHASH_ALLOCATOR_INIT(C, N, Tag, f)
# define LKRHASH_ALLOCATOR_UNINIT(C)
class CLKRhashAllocator
{
public:
static const TCHAR* ClassName() {return _TEXT("global new");}
};
#endif // !LKRHASH_ALLOCATOR_NEW
#ifndef __LKRHASH_NO_NAMESPACE__
namespace LKRhash {
#endif // !__LKRHASH_NO_NAMESPACE__
//--------------------------------------------------------------------
// forward declarations
class IRTL_DLLEXP CLKRLinearHashTable;
class IRTL_DLLEXP CLKRHashTable;
template <class _Der, class _Rcd, class _Ky, class _HT
#ifdef LKR_DEPRECATED_ITERATORS
, class _Iter
#endif // LKR_DEPRECATED_ITERATORS
>
class CTypedHashTable;
class CNodeClump;
class CBucket;
class CSegment;
class CDirEntry;
class IRTL_DLLEXP CLKRHashTableStats;
//--------------------------------------------------------------------
// Statistical information returned by GetStatistics
//--------------------------------------------------------------------
#ifdef LOCK_INSTRUMENTATION
class IRTL_DLLEXP CAveragedLockStats : public CLockStatistics
{
public:
int m_nItems;
CAveragedLockStats();
}; // class CAveragedLockStats
#endif // LOCK_INSTRUMENTATION
#ifndef LKRHASH_KERNEL_MODE
class IRTL_DLLEXP CLKRHashTableStats
{
public:
int RecordCount; // number of records in the table
int TableSize; // table size in number of slots
int DirectorySize; // number of entries in directory
int LongestChain; // longest hash chain in the table
int EmptySlots; // number of unused hash slots
double SplitFactor; // fraction of buckets split
double AvgSearchLength; // average length of a successful search
double ExpSearchLength; // theoretically expected length
double AvgUSearchLength; // average length of an unsuccessful search
double ExpUSearchLength; // theoretically expected length
int NodeClumpSize; // number of slots in a node clump
int CBucketSize; // sizeof(CBucket)
#ifdef LOCK_INSTRUMENTATION
CAveragedLockStats m_alsTable; // stats for table lock
CAveragedLockStats m_alsBucketsAvg; // avg of stats for bucket locks
CGlobalLockStatistics m_gls; // global statistics for all locks
#endif // LOCK_INSTRUMENTATION
enum {
MAX_BUCKETS = 40,
};
// histogram of bucket lengths
LONG m_aBucketLenHistogram[MAX_BUCKETS];
CLKRHashTableStats();
static const LONG*
BucketSizes();
static LONG
BucketSize(
LONG nBucketIndex);
static LONG
BucketIndex(
LONG nBucketLength);
}; // class CLKRHashTableStats
#endif // !LKRHASH_KERNEL_MODE
//--------------------------------------------------------------------
// Global table lock code. This is only used to measure how much of a
// slowdown having a global lock on the CLKRHashTable causes. It is
// *never* used in production code.
// #define LKRHASH_GLOBAL_LOCK CCritSec
#ifdef LKRHASH_GLOBAL_LOCK
# define LKRHASH_GLOBAL_LOCK_DECLARATIONS() \
typedef LKRHASH_GLOBAL_LOCK GlobalLock; \
mutable GlobalLock m_lkGlobal;
# define LKRHASH_GLOBAL_READ_LOCK() m_lkGlobal.ReadLock()
# define LKRHASH_GLOBAL_WRITE_LOCK() m_lkGlobal.WriteLock()
# define LKRHASH_GLOBAL_READ_UNLOCK() m_lkGlobal.ReadUnlock()
# define LKRHASH_GLOBAL_WRITE_UNLOCK() m_lkGlobal.WriteUnlock()
#else // !LKRHASH_GLOBAL_LOCK
# define LKRHASH_GLOBAL_LOCK_DECLARATIONS()
// These ones will be optimized away by the compiler
# define LKRHASH_GLOBAL_READ_LOCK() ((void)0)
# define LKRHASH_GLOBAL_WRITE_LOCK() ((void)0)
# define LKRHASH_GLOBAL_READ_UNLOCK() ((void)0)
# define LKRHASH_GLOBAL_WRITE_UNLOCK() ((void)0)
#endif // !LKRHASH_GLOBAL_LOCK
// Class for nodes on a bucket chain. Instead of a node containing
// one (signature, record-pointer, next-tuple-pointer) tuple, it
// contains _N_ such tuples. (N-1 next-tuple-pointers are omitted.)
// This improves locality of reference greatly; i.e., it's L1
// cache-friendly. It also reduces memory fragmentation and memory
// allocator overhead. It does complicate the chain traversal code
// slightly, admittedly.
//
// This theory is beautiful. In practice, however, CNodeClumps
// are *not* perfectly aligned on 32-byte boundaries by the memory
// allocators. Experimental results indicate that we get a 2-3%
// speed improvement by using 32-byte-aligned blocks, but this must
// be considered against the average of 16 bytes wasted per block.
class CNodeClump
{
public:
// Record slots per chunk - set so a chunk matches (one or two)
// cache lines. 3 ==> 32 bytes, 7 ==> 64 bytes, on 32-bit system.
// Note: the default max load factor is 7, which implies that
// there will seldom be more than one node clump in a chain.
enum {
#if defined(LOCK_INSTRUMENTATION)
BUCKET_BYTE_SIZE = 96,
#else
BUCKET_BYTE_SIZE = 64,
#endif
BUCKET_OVERHEAD = sizeof(LKR_BUCKET_LOCK) + sizeof(CNodeClump*),
NODE_SIZE = sizeof(const void*) + sizeof(DWORD),
NODES_PER_CLUMP = (BUCKET_BYTE_SIZE - BUCKET_OVERHEAD) / NODE_SIZE
};
enum {
// See if countdown loops are faster than countup loops for
// traversing a CNodeClump. In practice, countup loops are faster.
#ifndef LKR_COUNTDOWN
NODE_BEGIN = 0,
NODE_END = NODES_PER_CLUMP,
NODE_STEP = +1,
// for (int x = 0; x < NODES_PER_CLUMP; ++x) ...
#else // LKR_COUNTDOWN
NODE_BEGIN = NODES_PER_CLUMP-1,
NODE_END = -1,
NODE_STEP = -1,
// for (int x = NODES_PER_CLUMP; --x >= 0; ) ...
#endif // LKR_COUNTDOWN
};
enum {
#ifndef __HASHFN_NO_NAMESPACE__
HASH_INVALID_SIGNATURE = HashFn::HASH_INVALID_SIGNATURE,
#else // !__HASHFN_NO_NAMESPACE__
HASH_INVALID_SIGNATURE = ::HASH_INVALID_SIGNATURE,
#endif // !__HASHFN_NO_NAMESPACE__
};
DWORD m_dwKeySigs[NODES_PER_CLUMP]; // hash values computed from keys
CNodeClump* m_pncNext; // next node clump on the chain
const void* m_pvNode[NODES_PER_CLUMP]; // pointers to records
CNodeClump()
{
Clear();
}
void
Clear()
{
m_pncNext = NULL; // no dangling pointers
for (int i = NODES_PER_CLUMP; --i >= 0; )
{
m_dwKeySigs[i] = HASH_INVALID_SIGNATURE;
m_pvNode[i] = NULL;
}
}
bool
InvalidSignature(
int i) const
{
IRTLASSERT(0 <= i && i < NODES_PER_CLUMP);
return (m_dwKeySigs[i] == HASH_INVALID_SIGNATURE);
}
bool
IsEmptyNode(
int i) const
{
IRTLASSERT(0 <= i && i < NODES_PER_CLUMP);
return (m_pvNode[i] == NULL);
}
bool
IsEmptyAndInvalid(
int i) const
{
return IsEmptyNode(i) && InvalidSignature(i);
}
bool
IsEmptySlot(
int i) const
{
return InvalidSignature(i);
}
bool
IsLastClump() const
{
return (m_pncNext == NULL);
}
#ifdef IRTLDEBUG
// Don't want overhead of calls to dtor in retail build
~CNodeClump()
{
IRTLASSERT(IsLastClump()); // no dangling pointers
for (int i = NODES_PER_CLUMP; --i >= 0; )
IRTLASSERT(InvalidSignature(i) && IsEmptyNode(i));
}
#endif // IRTLDEBUG
LKRHASH_ALLOCATOR_DEFINITIONS(CNodeClump);
}; // class CNodeClump
#ifdef LKR_STL_ITERATORS
class IRTL_DLLEXP CLKRLinearHashTable_Iterator;
class IRTL_DLLEXP CLKRHashTable_Iterator;
class IRTL_DLLEXP CLKRLinearHashTable_Iterator
{
friend class CLKRLinearHashTable;
friend class CLKRHashTable;
friend class CLKRHashTable_Iterator;
protected:
CLKRLinearHashTable* m_plht; // which linear hash table?
CNodeClump* m_pnc; // a CNodeClump in bucket
DWORD m_dwBucketAddr;// bucket index
short m_iNode; // offset within m_pnc
enum {
NODES_PER_CLUMP = CNodeClump::NODES_PER_CLUMP,
NODE_BEGIN = CNodeClump::NODE_BEGIN,
NODE_END = CNodeClump::NODE_END,
NODE_STEP = CNodeClump::NODE_STEP,
};
CLKRLinearHashTable_Iterator(
CLKRLinearHashTable* plht,
CNodeClump* pnc,
DWORD dwBucketAddr,
short iNode)
: m_plht(plht),
m_pnc(pnc),
m_dwBucketAddr(dwBucketAddr),
m_iNode(iNode)
{
LKR_ITER_TRACE(_TEXT(" LKLH::prot ctor, this=%p, plht=%p, ")
_TEXT("pnc=%p, ba=%d, in=%d\n"),
this, plht, pnc, dwBucketAddr, iNode);
}
inline void _AddRef(
LK_ADDREF_REASON lkar) const;
bool _Increment(
bool fDecrementOldValue=true);
public:
CLKRLinearHashTable_Iterator()
: m_plht(NULL),
m_pnc(NULL),
m_dwBucketAddr(0),
m_iNode(0)
{
LKR_ITER_TRACE(_TEXT(" LKLH::default ctor, this=%p\n"), this);
}
CLKRLinearHashTable_Iterator(
const CLKRLinearHashTable_Iterator& rhs)
: m_plht(rhs.m_plht),
m_pnc(rhs.m_pnc),
m_dwBucketAddr(rhs.m_dwBucketAddr),
m_iNode(rhs.m_iNode)
{
LKR_ITER_TRACE(_TEXT(" LKLH::copy ctor, this=%p, rhs=%p\n"),
this, &rhs);
_AddRef(LKAR_ITER_COPY_CTOR);
}
CLKRLinearHashTable_Iterator& operator=(
const CLKRLinearHashTable_Iterator& rhs)
{
LKR_ITER_TRACE(_TEXT(" LKLH::operator=, this=%p, rhs=%p\n"),
this, &rhs);
rhs._AddRef(LKAR_ITER_ASSIGN_ACQUIRE);
this->_AddRef(LKAR_ITER_ASSIGN_RELEASE);
m_plht = rhs.m_plht;
m_pnc = rhs.m_pnc;
m_dwBucketAddr = rhs.m_dwBucketAddr;
m_iNode = rhs.m_iNode;
return *this;
}
~CLKRLinearHashTable_Iterator()
{
LKR_ITER_TRACE(_TEXT(" LKLH::dtor, this=%p, plht=%p\n"),
this, m_plht);
_AddRef(LKAR_ITER_DTOR);
}
bool Increment()
{
return IsValid() ? _Increment() : false;
}
bool IsValid() const
{
bool fValid = (m_plht != NULL && m_pnc != NULL
&& 0 <= m_iNode && m_iNode < NODES_PER_CLUMP);
if (fValid)
fValid = (m_pnc->m_pvNode[m_iNode] != NULL);
IRTLASSERT(fValid);
return fValid;
}
const void* Record() const
{
IRTLASSERT(IsValid());
return m_pnc->m_pvNode[m_iNode];
}
inline const DWORD_PTR Key() const;
bool operator==(
const CLKRLinearHashTable_Iterator& rhs) const
{
LKR_ITER_TRACE(_TEXT(" LKLH::operator==, this=%p, rhs=%p\n"),
this, &rhs);
// m_pnc and m_iNode uniquely identify an iterator
bool fEQ = ((m_pnc == rhs.m_pnc) // most unique field
&& (m_iNode == rhs.m_iNode));
IRTLASSERT(!fEQ || ((m_plht == rhs.m_plht)
&& (m_dwBucketAddr == rhs.m_dwBucketAddr)));
return fEQ;
}
bool operator!=(
const CLKRLinearHashTable_Iterator& rhs) const
{
LKR_ITER_TRACE(_TEXT(" LKLH::operator!=, this=%p, rhs=%p\n"),
this, &rhs);
bool fNE = ((m_pnc != rhs.m_pnc)
|| (m_iNode != rhs.m_iNode));
//// IRTLASSERT(fNE == !this->operator==(rhs));
return fNE;
}
}; // class CLKRLinearHashTable_Iterator
class IRTL_DLLEXP CLKRHashTable_Iterator
{
friend class CLKRHashTable;
protected:
// order important to minimize size
CLKRHashTable* m_pht; // which hash table?
CLKRLinearHashTable_Iterator m_subiter; // iterator into subtable
short m_ist; // index of subtable
CLKRHashTable_Iterator(
CLKRHashTable* pht,
short ist)
: m_pht(pht),
m_subiter(CLKRLinearHashTable_Iterator()), // zero
m_ist(ist)
{
LKR_ITER_TRACE(_TEXT(" LKHT::prot ctor, this=%p, pht=%p, ist=%d\n"),
this, pht, ist);
}
bool _Increment(
bool fDecrementOldValue=true);
public:
CLKRHashTable_Iterator()
: m_pht(NULL),
m_subiter(CLKRLinearHashTable_Iterator()), // zero
m_ist(0)
{
LKR_ITER_TRACE(_TEXT(" LKHT::default ctor, this=%p\n"), this);
}
#ifdef IRTLDEBUG
// Compiler does a perfectly adequate job of synthesizing these
// methods.
CLKRHashTable_Iterator(
const CLKRHashTable_Iterator& rhs)
: m_pht(rhs.m_pht),
m_subiter(rhs.m_subiter),
m_ist(rhs.m_ist)
{
LKR_ITER_TRACE(_TEXT(" LKHT::copy ctor, this=%p, rhs=%p\n"),
this, &rhs);
}
CLKRHashTable_Iterator& operator=(
const CLKRHashTable_Iterator& rhs)
{
LKR_ITER_TRACE(_TEXT(" LKHT::operator=, this=%p, rhs=%p\n"),
this, &rhs);
m_ist = rhs.m_ist;
m_subiter = rhs.m_subiter;
m_pht = rhs.m_pht;
return *this;
}
~CLKRHashTable_Iterator()
{
LKR_ITER_TRACE(_TEXT(" LKHT::dtor, this=%p, pht=%p\n"), this, m_pht);
}
#endif
bool Increment()
{
return IsValid() ? _Increment() : false;
}
bool IsValid() const
{
bool fValid = (m_pht != NULL && m_ist >= 0);
IRTLASSERT(fValid);
fValid = fValid && (m_subiter.m_plht != NULL);
IRTLASSERT(fValid);
fValid = fValid && (m_subiter.m_pnc != NULL);
IRTLASSERT(fValid);
fValid = fValid && (0 <= m_subiter.m_iNode);
IRTLASSERT(fValid);
fValid = fValid && (m_subiter.m_iNode < CNodeClump::NODES_PER_CLUMP);
IRTLASSERT(fValid);
if (fValid)
fValid = (m_subiter.m_pnc->m_pvNode[m_subiter.m_iNode] != NULL);
IRTLASSERT(fValid);
return fValid;
}
const void* Record() const
{
IRTLASSERT(IsValid());
return m_subiter.Record();
}
const DWORD_PTR Key() const
{
IRTLASSERT(IsValid());
return m_subiter.Key();
}
bool operator==(
const CLKRHashTable_Iterator& rhs) const
{
LKR_ITER_TRACE(_TEXT(" LKHT::operator==, this=%p, rhs=%p\n"),
this, &rhs);
// m_pnc and m_iNode uniquely identify an iterator
bool fEQ = ((m_subiter.m_pnc
== rhs.m_subiter.m_pnc) // most unique field
&& (m_subiter.m_iNode == rhs.m_subiter.m_iNode));
IRTLASSERT(!fEQ
|| ((m_ist == rhs.m_ist)
&& (m_pht == rhs.m_pht)
&& (m_subiter.m_plht == rhs.m_subiter.m_plht)
&& (m_subiter.m_dwBucketAddr
== rhs.m_subiter.m_dwBucketAddr)));
return fEQ;
}
bool operator!=(
const CLKRHashTable_Iterator& rhs) const
{
LKR_ITER_TRACE(_TEXT(" LKHT::operator!=, this=%p, rhs=%p\n"),
this, &rhs);
bool fNE = ((m_subiter.m_pnc != rhs.m_subiter.m_pnc)
|| (m_subiter.m_iNode != rhs.m_subiter.m_iNode));
//// IRTLASSERT(fNE == !this->operator==(rhs));
return fNE;
}
}; // class CLKRHashTable_Iterator
#endif // LKR_STL_ITERATORS
//--------------------------------------------------------------------
// CLKRLinearHashTable
//
// A thread-safe linear hash table.
//--------------------------------------------------------------------
class IRTL_DLLEXP CLKRLinearHashTable
{
public:
typedef LKR_TABLE_LOCK TableLock;
typedef LKR_BUCKET_LOCK BucketLock;
#ifdef LKR_DEPRECATED_ITERATORS
class CIterator;
friend class CLKRLinearHashTable::CIterator;
#endif // LKR_DEPRECATED_ITERATORS
#ifdef LKR_STL_ITERATORS
friend class CLKRLinearHashTable_Iterator;
typedef CLKRLinearHashTable_Iterator Iterator;
#endif // LKR_STL_ITERATORS
private:
friend class CNodeClump;
friend class CLKRHashTable;
friend BOOL LKR_Initialize();
friend void LKR_Terminate();
#ifdef LKRHASH_INSTRUMENTATION
// TODO
#endif // LKRHASH_INSTRUMENTATION
public:
// aliases for convenience
enum {
NODES_PER_CLUMP = CNodeClump::NODES_PER_CLUMP,
MIN_DIRSIZE = 1<<3, // CDirEntry::MIN_DIRSIZE
MAX_DIRSIZE = 1<<20, // CDirEntry::MAX_DIRSIZE
NAME_SIZE = 16, // includes trailing '\0'
NODE_BEGIN = CNodeClump::NODE_BEGIN,
NODE_END = CNodeClump::NODE_END,
NODE_STEP = CNodeClump::NODE_STEP,
HASH_INVALID_SIGNATURE = CNodeClump::HASH_INVALID_SIGNATURE,
};
private:
//
// Miscellaneous helper functions
//
// Convert a hash signature to a bucket address
inline DWORD _BucketAddress(DWORD dwSignature) const;
// See the Linear Hashing paper
static DWORD _H0(DWORD dwSignature, DWORD dwBktAddrMask);
DWORD _H0(DWORD dwSignature) const;
// See the Linear Hashing paper. Preserves one bit more than _H0.
static DWORD _H1(DWORD dwSignature, DWORD dwBktAddrMask);
DWORD _H1(DWORD dwSignature) const;
// In which segment within the directory does the bucketaddress lie?
// (Return type must be lvalue so that it can be assigned to.)
CSegment*& _Segment(DWORD dwBucketAddr) const;
// Offset within the segment of the bucketaddress
DWORD _SegIndex(DWORD dwBucketAddr) const;
// Convert a bucketaddress to a CBucket*
inline CBucket* _Bucket(DWORD dwBucketAddr) const;
// Extract the key from a record
const DWORD_PTR _ExtractKey(const void* pvRecord) const;
// Hash the key
DWORD _CalcKeyHash(const DWORD_PTR pnKey) const;
// Compare two keys for equality
BOOL _EqualKeys(const DWORD_PTR pnKey1,
const DWORD_PTR pnKey2) const;
// AddRef or Release a record.
void _AddRefRecord(const void* pvRecord,
LK_ADDREF_REASON lkar) const;
// Find a bucket, given its signature.
CBucket* _FindBucket(DWORD dwSignature,
bool fLockForWrite) const;
// Used by _FindKey so that the thread won't deadlock if the user has
// already explicitly called table->WriteLock().
bool _ReadOrWriteLock() const;
void _ReadOrWriteUnlock(bool fReadLocked) const;
// Memory allocation wrappers to allow us to simulate allocation
// failures during testing
static CDirEntry* const
_AllocateSegmentDirectory(
size_t n);
bool
_FreeSegmentDirectory();
static CNodeClump* const
_AllocateNodeClump();
static bool
_FreeNodeClump(
CNodeClump* pnc);
CSegment* const
_AllocateSegment() const;
bool
_FreeSegment(
CSegment* pseg) const;
LK_RETCODE
_InitializeSegmentDirectory();
#ifdef LOCK_INSTRUMENTATION
static LONG sm_cTables;
static const TCHAR*
_LockName()
{
LONG l = ++sm_cTables;
// possible race condition but we don't care, as this is never
// used in production code
static TCHAR s_tszName[CLockStatistics::L_NAMELEN];
wsprintf(s_tszName, _TEXT("LH%05x"), 0xFFFFF & l);
return s_tszName;
}
// Statistics for the table lock
CLockStatistics _LockStats() const
{ return m_Lock.Statistics(); }
#endif // LOCK_INSTRUMENTATION
private:
// Fields are ordered so as to minimize number of cache lines touched
DWORD m_dwSignature; // debugging: id & corruption check
CHAR m_szName[NAME_SIZE]; // an identifier for debugging
mutable LK_RETCODE m_lkrcState; // Internal state of table
mutable TableLock m_Lock; // Lock on entire linear hash table
// type-specific function pointers
LKR_PFnExtractKey m_pfnExtractKey; // Extract key from record
LKR_PFnCalcKeyHash m_pfnCalcKeyHash; // Calculate hash signature of key
LKR_PFnEqualKeys m_pfnEqualKeys; // Compare two keys
LKR_PFnAddRefRecord m_pfnAddRefRecord; // AddRef a record
LK_TABLESIZE m_lkts; // "size" of table: small, medium, or large
DWORD m_dwSegBits; // C{Small,Medium,Large}Segment::SEGBITS
DWORD m_dwSegSize; // C{Small,Medium,Large}Segment::SEGSIZE
DWORD m_dwSegMask; // C{Small,Medium,Large}Segment::SEGMASK
DWORD m_dwBktAddrMask0; // mask used for address calculation
DWORD m_dwBktAddrMask1; // used in _H1 calculation
DWORD m_iExpansionIdx; // address of next bucket to be expanded
CDirEntry* m_paDirSegs; // directory of table segments
DWORD m_cDirSegs; // segment directory size: varies between
// MIN_DIRSIZE and MAX_DIRSIZE
DWORD m_nLevel; // number of table doublings performed
DWORD m_cRecords; // number of records in the table
DWORD m_cActiveBuckets; // number of buckets in use (table size)
WORD m_wBucketLockSpins;// default spin count for bucket locks
const BYTE m_nTableLockType; // for debugging: LOCK_SPINLOCK, etc
const BYTE m_nBucketLockType;// for debugging: LOCK_SPINLOCK, etc
const CLKRHashTable* const m_phtParent;// Owning table. NULL => standalone
BYTE m_MaxLoad; // max load factor (average chain length)
const bool m_fMultiKeys; // Allow multiple identical keys?
const bool m_fNonPagedAllocs;// Use paged or NP pool in kernel
DWORD_PTR m_pvReserved1; // Reserved for future debugging needs
DWORD_PTR m_pvReserved2; // Reserved for future debugging needs
DWORD_PTR m_pvReserved3; // Reserved for future debugging needs
DWORD_PTR m_pvReserved4; // Reserved for future debugging needs
#ifndef LKR_NO_GLOBAL_LIST
static CLockedDoubleList sm_llGlobalList;// All active CLKRLinearHashTables
CListEntry m_leGlobalList;
#endif // !LKR_NO_GLOBAL_LIST
void _InsertThisIntoGlobalList()
{
#ifndef LKR_NO_GLOBAL_LIST
// Only add standalone CLKRLinearHashTables to global list.
// CLKRHashTables have their own global list.
if (m_phtParent == NULL)
sm_llGlobalList.InsertHead(&m_leGlobalList);
#endif // !LKR_NO_GLOBAL_LIST
}
void _RemoveThisFromGlobalList()
{
#ifndef LKR_NO_GLOBAL_LIST
if (m_phtParent == NULL)
sm_llGlobalList.RemoveEntry(&m_leGlobalList);
#endif // !LKR_NO_GLOBAL_LIST
}
// Non-trivial implementation functions
LK_RETCODE _InsertRecord(const void* pvRecord, DWORD dwSignature,
bool fOverwrite
#ifdef LKR_STL_ITERATORS
, Iterator* piterResult=NULL
#endif // LKR_STL_ITERATORS
);
LK_RETCODE _DeleteKey(const DWORD_PTR pnKey, DWORD dwSignature,
bool fDeleteAllSame);
LK_RETCODE _DeleteRecord(const void* pvRecord, DWORD dwSignature);
bool _DeleteNode(CBucket* pbkt, CNodeClump*& rpnc,
CNodeClump*& rpncPrev, int& riNode,
LK_ADDREF_REASON lkar);
LK_RETCODE _FindKey(const DWORD_PTR pnKey, DWORD dwSignature,
const void** ppvRecord
#ifdef LKR_STL_ITERATORS
, Iterator* piterResult=NULL
#endif // LKR_STL_ITERATORS
) const;
LK_RETCODE _FindRecord(const void* pvRecord,
DWORD dwSignature) const;
// returns count of errors in compacted state => 0 is good
int _IsNodeCompact(CBucket* const pbkt) const;
#ifdef LKR_APPLY_IF
// Predicate functions
static LK_PREDICATE WINAPI
_PredTrue(const void* /*pvRecord*/, void* /*pvState*/)
{ return LKP_PERFORM; }
DWORD _ApplyIf(LKR_PFnRecordPred pfnPredicate,
LKR_PFnRecordAction pfnAction, void* pvState,
LK_LOCKTYPE lkl, LK_PREDICATE& rlkp);
DWORD _DeleteIf(LKR_PFnRecordPred pfnPredicate, void* pvState,
LK_PREDICATE& rlkp);
#endif // LKR_APPLY_IF
void _Clear(bool fShrinkDirectory);
LK_RETCODE _SetSegVars(LK_TABLESIZE lkts, DWORD cInitialBuckets);
LK_RETCODE _Expand();
LK_RETCODE _Contract();
LK_RETCODE _SplitRecordSet(CNodeClump* pncOldTarget,
CNodeClump* pncNewTarget,
DWORD iExpansionIdx,
DWORD dwBktAddrMask,
DWORD dwNewBkt,
CNodeClump* pncFreeList);
LK_RETCODE _MergeRecordSets(CBucket* pbktNewTarget,
CNodeClump* pncOldList,
CNodeClump* pncFreeList);
// Private copy ctor and op= to prevent compiler synthesizing them.
// Must provide a (bad) implementation because we export instantiations.
// TODO: implement these properly; they could be useful.
CLKRLinearHashTable(const CLKRLinearHashTable&)
: m_dwSignature(SIGNATURE_FREE)
#ifdef LOCK_INSTRUMENTATION
, m_Lock(NULL)
#endif // LOCK_INSTRUMENTATION
, m_nTableLockType(0),
m_nBucketLockType(0),
m_fMultiKeys(false),
m_fNonPagedAllocs(false),
m_phtParent(NULL)
{*(BYTE*)NULL;}
CLKRLinearHashTable& operator=(const CLKRLinearHashTable&)
{return *(CLKRLinearHashTable*)NULL;}
private:
// This ctor is used by CLKRHashTable
CLKRLinearHashTable(
LPCSTR pszName, // Identifies table for debugging
LKR_PFnExtractKey pfnExtractKey, // Extract key from record
LKR_PFnCalcKeyHash pfnCalcKeyHash, // Calculate hash signature of key
LKR_PFnEqualKeys pfnEqualKeys, // Compare two keys
LKR_PFnAddRefRecord pfnAddRefRecord,// AddRef in FindKey, etc
unsigned maxload, // Upperbound on avg chain length
DWORD initsize, // Initial size of hash table.
CLKRHashTable* phtParent, // Owning table.
bool fMultiKeys, // Allow multiple identical keys?
bool fNonPagedAllocs // use paged or NP pool in kernel
);
LK_RETCODE
_Initialize(
LKR_PFnExtractKey pfnExtractKey,
LKR_PFnCalcKeyHash pfnCalcKeyHash,
LKR_PFnEqualKeys pfnEqualKeys,
LKR_PFnAddRefRecord pfnAddRefRecord,
LPCSTR pszName,
unsigned maxload,
DWORD initsize);
public:
CLKRLinearHashTable(
LPCSTR pszName, // Identifies table for debugging
LKR_PFnExtractKey pfnExtractKey, // Extract key from record
LKR_PFnCalcKeyHash pfnCalcKeyHash, // Calculate hash signature of key
LKR_PFnEqualKeys pfnEqualKeys, // Compare two keys
LKR_PFnAddRefRecord pfnAddRefRecord,// AddRef in FindKey, etc
unsigned maxload=LK_DFLT_MAXLOAD,// Upperbound on average chain length
DWORD initsize=LK_DFLT_INITSIZE, // Initial size of hash table.
DWORD num_subtbls=LK_DFLT_NUM_SUBTBLS, // for signature compatiblity
// with CLKRHashTable
bool fMultiKeys=false // Allow multiple identical keys?
#ifdef LKRHASH_KERNEL_MODE
, bool fNonPagedAllocs=true // use paged or NP pool
#endif
);
~CLKRLinearHashTable();
static const TCHAR* ClassName()
{return _TEXT("CLKRLinearHashTable");}
int NumSubTables() const {return 1;}
bool MultiKeys() const
{
return false;
// return m_fMultiKeys; // TODO: implement
}
#ifdef LKRHASH_KERNEL_MODE
bool NonPagedAllocs() const
{
return m_fNonPagedAllocs;
}
#endif
static LK_TABLESIZE NumSubTables(DWORD& rinitsize, DWORD& rnum_subtbls);
// Insert a new record into hash table.
// Returns LK_SUCCESS if all OK, LK_KEY_EXISTS if same key already
// exists (unless fOverwrite), LK_ALLOC_FAIL if out of space,
// or LK_BAD_RECORD for a bad record.
LK_RETCODE InsertRecord(const void* pvRecord, bool fOverwrite=false)
{
if (!IsUsable())
return m_lkrcState;
if (pvRecord == NULL)
return LK_BAD_RECORD;
return _InsertRecord(pvRecord, _CalcKeyHash(_ExtractKey(pvRecord)),
fOverwrite);
}
// Delete record with the given key.
// Returns LK_SUCCESS if all OK, or LK_NO_SUCH_KEY if not found
LK_RETCODE DeleteKey(const DWORD_PTR pnKey,
bool fDeleteAllSame=false)
{
if (!IsUsable())
return m_lkrcState;
return _DeleteKey(pnKey, _CalcKeyHash(pnKey), fDeleteAllSame);
}
// Delete a record from the table, if present.
// Returns LK_SUCCESS if all OK, or LK_NO_SUCH_KEY if not found
LK_RETCODE DeleteRecord(const void* pvRecord)
{
if (!IsUsable())
return m_lkrcState;
if (pvRecord == NULL)
return LK_BAD_RECORD;
return _DeleteRecord(pvRecord, _CalcKeyHash(_ExtractKey(pvRecord)));
}
// Find record with given key.
// Returns: LK_SUCCESS, if record found (record is returned in *ppvRecord)
// LK_BAD_RECORD, if ppvRecord is invalid
// LK_NO_SUCH_KEY, if no record with given key value was found
// LK_UNUSABLE, if hash table not in usable state
// Note: the record is AddRef'd. You must decrement the reference
// count when you are finished with the record (if you're implementing
// refcounting semantics).
LK_RETCODE FindKey(const DWORD_PTR pnKey,
const void** ppvRecord) const
{
if (!IsUsable())
return m_lkrcState;
if (ppvRecord == NULL)
return LK_BAD_RECORD;
return _FindKey(pnKey, _CalcKeyHash(pnKey), ppvRecord);
}
// Sees if the record is contained in the table
// Returns: LK_SUCCESS, if record found
// LK_BAD_RECORD, if pvRecord is invalid
// LK_NO_SUCH_KEY, if record is not in the table
// LK_UNUSABLE, if hash table not in usable state
// Note: the record is *not* AddRef'd.
LK_RETCODE FindRecord(const void* pvRecord) const
{
if (!IsUsable())
return m_lkrcState;
if (pvRecord == NULL)
return LK_BAD_RECORD;
return _FindRecord(pvRecord, _CalcKeyHash(_ExtractKey(pvRecord)));
}
#ifdef LKR_APPLY_IF
// Walk the hash table, applying pfnAction to all records.
// Locks the whole table for the duration with either a (possibly
// shared) readlock or a writelock, according to lkl.
// Loop is aborted if pfnAction returns LKA_ABORT.
// Returns the number of successful applications.
DWORD Apply(LKR_PFnRecordAction pfnAction,
void* pvState=NULL,
LK_LOCKTYPE lkl=LKL_READLOCK);
// Walk the hash table, applying pfnAction to any records that match
// pfnPredicate. Locks the whole table for the duration with either
// a (possibly shared) readlock or a writelock, according to lkl.
// Loop is aborted if pfnAction returns LKA_ABORT.
// Returns the number of successful applications.
DWORD ApplyIf(LKR_PFnRecordPred pfnPredicate,
LKR_PFnRecordAction pfnAction,
void* pvState=NULL,
LK_LOCKTYPE lkl=LKL_READLOCK);
// Delete any records that match pfnPredicate.
// Locks the table for the duration with a writelock.
// Returns the number of deletions.
//
// Do *not* walk the hash table by hand with an iterator and call
// DeleteKey. The iterator will end up pointing to garbage.
DWORD DeleteIf(LKR_PFnRecordPred pfnPredicate,
void* pvState=NULL);
#endif // LKR_APPLY_IF
// Check table for consistency. Returns 0 if okay, or the number of
// errors otherwise.
int CheckTable() const;
// Remove all data from the table
void Clear()
{
WriteLock();
_Clear(true);
WriteUnlock();
}
// Number of elements in the table
DWORD Size() const
{ return m_cRecords; }
// Maximum possible number of elements in the table
DWORD MaxSize() const
{ return static_cast<DWORD>(m_MaxLoad * MAX_DIRSIZE * m_dwSegSize); }
// Get hash table statistics
CLKRHashTableStats GetStatistics() const;
// Is the hash table usable?
bool IsUsable() const
{ return (m_lkrcState == LK_SUCCESS); }
// Is the hash table consistent and correct?
bool IsValid() const
{
STATIC_ASSERT(((MIN_DIRSIZE & (MIN_DIRSIZE-1)) == 0) // == (1 << N)
&& ((1 << 3) <= MIN_DIRSIZE)
&& (MIN_DIRSIZE < MAX_DIRSIZE)
&& ((MAX_DIRSIZE & (MAX_DIRSIZE-1)) == 0)
&& (MAX_DIRSIZE <= (1 << 30)));
bool f = (m_lkrcState == LK_SUCCESS // serious internal failure?
&& m_paDirSegs != NULL
&& MIN_DIRSIZE <= m_cDirSegs && m_cDirSegs <= MAX_DIRSIZE
&& (m_cDirSegs & (m_cDirSegs-1)) == 0
&& m_pfnExtractKey != NULL
&& m_pfnCalcKeyHash != NULL
&& m_pfnEqualKeys != NULL
&& m_pfnAddRefRecord != NULL
&& m_cActiveBuckets > 0
&& ValidSignature()
);
if (!f)
m_lkrcState = LK_UNUSABLE;
return f;
}
// Set the spin count on the table lock
void SetTableLockSpinCount(WORD wSpins);
// Get the spin count on the table lock
WORD GetTableLockSpinCount() const;
// Set/Get the spin count on the bucket locks
void SetBucketLockSpinCount(WORD wSpins);
WORD GetBucketLockSpinCount() const;
enum {
SIGNATURE = (('L') | ('K' << 8) | ('L' << 16) | ('H' << 24)),
SIGNATURE_FREE = (('L') | ('K' << 8) | ('L' << 16) | ('x' << 24)),
};
bool
ValidSignature() const
{ return m_dwSignature == SIGNATURE;}
#ifdef LKR_EXPOSED_TABLE_LOCK
public:
#else // !LKR_EXPOSED_TABLE_LOCK
protected:
#endif // !LKR_EXPOSED_TABLE_LOCK
//
// Lock manipulators
//
// Lock the table (exclusively) for writing
void WriteLock()
{ m_Lock.WriteLock(); }
// Lock the table (possibly shared) for reading
void ReadLock() const
{ m_Lock.ReadLock(); }
// Unlock the table for writing
void WriteUnlock()
{ m_Lock.WriteUnlock(); }
// Unlock the table for reading
void ReadUnlock() const
{ m_Lock.ReadUnlock(); }
// Is the table already locked for writing?
bool IsWriteLocked() const
{ return m_Lock.IsWriteLocked(); }
// Is the table already locked for reading?
bool IsReadLocked() const
{ return m_Lock.IsReadLocked(); }
// Is the table unlocked for writing?
bool IsWriteUnlocked() const
{ return m_Lock.IsWriteUnlocked(); }
// Is the table unlocked for reading?
bool IsReadUnlocked() const
{ return m_Lock.IsReadUnlocked(); }
// Convert the read lock to a write lock
void ConvertSharedToExclusive()
{ m_Lock.ConvertSharedToExclusive(); }
// Convert the write lock to a read lock
void ConvertExclusiveToShared() const
{ m_Lock.ConvertExclusiveToShared(); }
#ifdef LKRHASH_KERNEL_MODE
LKRHASH_ALLOCATOR_DEFINITIONS(CLKRLinearHashTable);
#endif // LKRHASH_KERNEL_MODE
#ifdef LKR_DEPRECATED_ITERATORS
public:
// Iterators can be used to walk the table. To ensure a consistent
// view of the data, the iterator locks the whole table. This can
// have a negative effect upon performance, because no other thread
// can do anything with the table. Use with care.
//
// You should not use an iterator to walk the table, calling DeleteKey,
// as the iterator will end up pointing to garbage.
//
// Use Apply, ApplyIf, or DeleteIf instead of iterators to safely
// walk the tree. Or use the STL-style iterators.
//
// Note that iterators acquire a reference to the record pointed to
// and release that reference as soon as the iterator is incremented.
// In other words, this code is safe:
// lkrc = ht.IncrementIterator(&iter);
// // assume lkrc == LK_SUCCESS for the sake of this example
// CMyHashTable::Record* pRec = iter.Record();
// Foo(pRec); // uses pRec but doesn't hang on to it
// lkrc = ht.IncrementIterator(&iter);
//
// But this code is not safe because pRec is used out of the scope of
// the iterator that provided it:
// lkrc = ht.IncrementIterator(&iter);
// CMyHashTable::Record* pRec = iter.Record();
// // Broken code: Should have called
// // ht.AddRefRecord(pRec, LKAR_EXPLICIT_ACQUIRE) here
// lkrc = ht.IncrementIterator(&iter);
// Foo(pRec); // Unsafe: because no longer have a valid reference
//
// If the record has no reference-counting semantics, then you can
// ignore the above remarks about scope.
class CIterator
{
protected:
friend class CLKRLinearHashTable;
CLKRLinearHashTable* m_plht; // which linear hash table?
DWORD m_dwBucketAddr; // bucket index
CNodeClump* m_pnc; // a CNodeClump in bucket
int m_iNode; // offset within m_pnc
LK_LOCKTYPE m_lkl; // readlock or writelock?
private:
// Private copy ctor and op= to prevent compiler synthesizing them.
// Must provide (bad) implementation because we export instantiations.
CIterator(const CIterator&) {*(BYTE*)NULL;}
CIterator& operator=(const CIterator&) {return *(CIterator*)NULL;}
public:
CIterator(
LK_LOCKTYPE lkl=LKL_WRITELOCK)
: m_plht(NULL),
m_dwBucketAddr(0),
m_pnc(NULL),
m_iNode(-1),
m_lkl(lkl)
{}
// Return the record associated with this iterator
const void* Record() const
{
IRTLASSERT(IsValid());
return ((m_pnc != NULL
&& m_iNode >= 0
&& m_iNode < CLKRLinearHashTable::NODES_PER_CLUMP)
? m_pnc->m_pvNode[m_iNode]
: NULL);
}
// Return the key associated with this iterator
const DWORD_PTR Key() const
{
IRTLASSERT(m_plht != NULL);
const void* pRec = Record();
return ((pRec != NULL && m_plht != NULL)
? m_plht->_ExtractKey(pRec)
: NULL);
}
bool IsValid() const
{
return ((m_plht != NULL)
&& (m_pnc != NULL)
&& (0 <= m_iNode
&& m_iNode < CLKRLinearHashTable::NODES_PER_CLUMP)
&& (!m_pnc->IsEmptyNode(m_iNode)));
}
// Delete the record that the iterator points to. Does an implicit
// IncrementIterator after deletion.
LK_RETCODE DeleteRecord();
// Change the record that the iterator points to. The new record
// must have the same key as the old one.
LK_RETCODE ChangeRecord(const void* pNewRec);
}; // class CIterator
// Const iterators for readonly access. You must use these with
// const CLKRLinearHashTables.
class CConstIterator : public CIterator
{
private:
// Private, unimplemented copy ctor and op= to prevent
// compiler synthesizing them.
CConstIterator(const CConstIterator&);
CConstIterator& operator=(const CConstIterator&);
public:
CConstIterator()
: CIterator(LKL_READLOCK)
{}
}; // class CConstIterator
private:
// The public APIs lock the table. The private ones, which are used
// directly by CLKRHashTable, don't.
LK_RETCODE _InitializeIterator(CIterator* piter);
LK_RETCODE _CloseIterator(CIterator* piter);
public:
// Initialize the iterator to point to the first item in the hash table
// Returns LK_SUCCESS, LK_NO_MORE_ELEMENTS, or LK_BAD_ITERATOR.
LK_RETCODE InitializeIterator(CIterator* piter)
{
IRTLASSERT(piter != NULL && piter->m_plht == NULL);
if (piter == NULL || piter->m_plht != NULL)
return LK_BAD_ITERATOR;
if (piter->m_lkl == LKL_WRITELOCK)
WriteLock();
else
ReadLock();
return _InitializeIterator(piter);
}
// The const iterator version
LK_RETCODE InitializeIterator(CConstIterator* piter) const
{
IRTLASSERT(piter != NULL && piter->m_plht == NULL);
IRTLASSERT(piter->m_lkl != LKL_WRITELOCK);
if (piter == NULL || piter->m_plht != NULL
|| piter->m_lkl == LKL_WRITELOCK)
return LK_BAD_ITERATOR;
ReadLock();
return const_cast<CLKRLinearHashTable*>(this)
->_InitializeIterator(static_cast<CIterator*>(piter));
}
// Move the iterator on to the next item in the table.
// Returns LK_SUCCESS, LK_NO_MORE_ELEMENTS, or LK_BAD_ITERATOR.
LK_RETCODE IncrementIterator(CIterator* piter);
LK_RETCODE IncrementIterator(CConstIterator* piter) const
{
IRTLASSERT(piter != NULL && piter->m_plht == this);
IRTLASSERT(piter->m_lkl != LKL_WRITELOCK);
if (piter == NULL || piter->m_plht != this
|| piter->m_lkl == LKL_WRITELOCK)
return LK_BAD_ITERATOR;
return const_cast<CLKRLinearHashTable*>(this)
->IncrementIterator(static_cast<CIterator*>(piter));
}
// Close the iterator.
LK_RETCODE CloseIterator(CIterator* piter)
{
IRTLASSERT(piter != NULL && piter->m_plht == this);
if (piter == NULL || piter->m_plht != this)
return LK_BAD_ITERATOR;
_CloseIterator(piter);
if (piter->m_lkl == LKL_WRITELOCK)
WriteUnlock();
else
ReadUnlock();
return LK_SUCCESS;
};
// Close the CConstIterator
LK_RETCODE CloseIterator(CConstIterator* piter) const
{
IRTLASSERT(piter != NULL && piter->m_plht == this);
IRTLASSERT(piter->m_lkl != LKL_WRITELOCK);
if (piter == NULL || piter->m_plht != this
|| piter->m_lkl == LKL_WRITELOCK)
return LK_BAD_ITERATOR;
const_cast<CLKRLinearHashTable*>(this)
->_CloseIterator(static_cast<CIterator*>(piter));
ReadUnlock();
return LK_SUCCESS;
};
#endif // LKR_DEPRECATED_ITERATORS
#ifdef LKR_STL_ITERATORS
private:
bool _Erase(Iterator& riter, DWORD dwSignature);
bool _Find(DWORD_PTR pnKey, DWORD dwSignature,
Iterator& riterResult);
bool _IsValidIterator(const Iterator& riter) const
{
LKR_ITER_TRACE(_TEXT(" LKLH:_IsValidIterator(%p)\n"), &riter);
bool fValid = ((riter.m_plht == this)
&& (riter.m_dwBucketAddr < m_cActiveBuckets)
&& riter.IsValid());
IRTLASSERT(fValid);
return fValid;
}
public:
// Return iterator pointing to first item in table
Iterator
Begin();
// Return a one-past-the-end iterator. Always empty.
Iterator
End() const
{
LKR_ITER_TRACE(_TEXT(" LKLH::End\n"));
return Iterator();
}
// Insert a record
// Returns `true' if successful; iterResult points to that record
// Returns `false' otherwise; iterResult == End()
bool
Insert(
/* in */ const void* pvRecord,
/* out */ Iterator& riterResult,
/* in */ bool fOverwrite=false);
// Erase the record pointed to by the iterator; adjust the iterator
// to point to the next record. Returns `true' if successful.
bool
Erase(
/* in,out */ Iterator& riter);
// Erase the records in the range [riterFirst, riterLast).
// Returns `true' if successful. riterFirst points to riterLast on return.
bool
Erase(
/*in*/ Iterator& riterFirst,
/*in*/ Iterator& riterLast);
// Find the (first) record that has its key == pnKey.
// If successful, returns `true' and iterator points to (first) record.
// If fails, returns `false' and iterator == End()
bool
Find(
/* in */ DWORD_PTR pnKey,
/* out */ Iterator& riterResult);
// Find the range of records that have their keys == pnKey.
// If successful, returns `true', iterFirst points to first record,
// and iterLast points to one-beyond-the last such record.
// If fails, returns `false' and both iterators == End().
// Primarily useful when m_fMultiKey == true
bool
EqualRange(
/* in */ DWORD_PTR pnKey,
/* out */ Iterator& riterFirst, // inclusive
/* out */ Iterator& riterLast); // exclusive
#endif // LKR_STL_ITERATORS
}; // class CLKRLinearHashTable
#ifdef LKR_STL_ITERATORS
// These functions have to be defined after CLKRLinearHashTable
inline void
CLKRLinearHashTable_Iterator::_AddRef(
LK_ADDREF_REASON lkar) const
{
// TODO: should iterator call _AddRefRecord at all
if (m_plht != NULL && m_iNode != NODE_BEGIN - NODE_STEP)
{
IRTLASSERT((0 <= m_iNode && m_iNode < NODES_PER_CLUMP)
&& (unsigned) m_iNode < NODES_PER_CLUMP
&& m_pnc != NULL
&& (lkar < 0 || lkar > 0)
);
const void* pvRecord = m_pnc->m_pvNode[m_iNode];
IRTLASSERT(pvRecord != NULL);
LKR_ITER_TRACE(_TEXT(" LKLH::AddRef, this=%p, Rec=%p\n"),
this, pvRecord);
m_plht->_AddRefRecord(pvRecord, lkar);
}
} // CLKRLinearHashTable_Iterator::_AddRef
inline const DWORD_PTR
CLKRLinearHashTable_Iterator::Key() const
{
IRTLASSERT(IsValid());
return m_plht->_ExtractKey(m_pnc->m_pvNode[m_iNode]);
} // CLKRLinearHashTable_Iterator::Key
#endif // LKR_STL_ITERATORS
//--------------------------------------------------------------------
// CLKRHashTable
//
// To improve concurrency, a hash table is divided into a number of
// (independent) subtables. Each subtable is a linear hash table. The
// number of subtables is defined when the table is created and remains
// fixed thereafter. Records are assigned to subtables based on their
// hashed key.
//
// For small or low-contention hashtables, you can bypass this
// thin wrapper and use CLKRLinearHashTable directly. The methods are
// documented in the declarations for CLKRHashTable (above).
//--------------------------------------------------------------------
class IRTL_DLLEXP CLKRHashTable
{
private:
typedef CLKRLinearHashTable SubTable;
public:
typedef SubTable::TableLock TableLock;
typedef SubTable::BucketLock BucketLock;
#ifdef LKR_DEPRECATED_ITERATORS
class CIterator;
friend class CLKRHashTable::CIterator;
#endif // LKR_DEPRECATED_ITERATORS
#ifdef LKR_STL_ITERATORS
friend class CLKRHashTable_Iterator;
typedef CLKRHashTable_Iterator Iterator;
#endif // LKR_STL_ITERATORS
friend class CLKRLinearHashTable;
// aliases for convenience
enum {
NAME_SIZE = SubTable::NAME_SIZE,
HASH_INVALID_SIGNATURE = SubTable::HASH_INVALID_SIGNATURE,
NODES_PER_CLUMP = SubTable::NODES_PER_CLUMP,
};
enum {
MAX_LKR_SUBTABLES = 64,
};
private:
// Hash table parameters
DWORD m_dwSignature; // debugging: id & corruption check
CHAR m_szName[NAME_SIZE]; // an identifier for debugging
DWORD m_cSubTables; // number of subtables
SubTable** m_palhtDir; // array of subtables
// type-specific function pointers
LKR_PFnExtractKey m_pfnExtractKey;
LKR_PFnCalcKeyHash m_pfnCalcKeyHash;
mutable LK_RETCODE m_lkrcState; // Internal state of table
int m_nSubTableMask;
#ifndef LKR_NO_GLOBAL_LIST
static CLockedDoubleList sm_llGlobalList; // All active CLKRHashTables
CListEntry m_leGlobalList;
#endif // !LKR_NO_GLOBAL_LIST
void
_InsertThisIntoGlobalList()
{
#ifndef LKR_NO_GLOBAL_LIST
sm_llGlobalList.InsertHead(&m_leGlobalList);
#endif // !LKR_NO_GLOBAL_LIST
}
void
_RemoveThisFromGlobalList()
{
#ifndef LKR_NO_GLOBAL_LIST
sm_llGlobalList.RemoveEntry(&m_leGlobalList);
#endif // !LKR_NO_GLOBAL_LIST
}
LKRHASH_GLOBAL_LOCK_DECLARATIONS();
// Private copy ctor and op= to prevent compiler synthesizing them.
// Must provide a (bad) implementation because we export instantiations.
// TODO: implement these properly; they could be useful.
CLKRHashTable(const CLKRHashTable&) {*(BYTE*)NULL;}
CLKRHashTable& operator=(const CLKRHashTable&) {return *(CLKRHashTable*)NULL;}
// Extract the key from the record
const DWORD_PTR _ExtractKey(const void* pvRecord) const
{
IRTLASSERT(pvRecord != NULL);
IRTLASSERT(m_pfnExtractKey != NULL);
return (*m_pfnExtractKey)(pvRecord);
}
// Hash the key
DWORD _CalcKeyHash(const DWORD_PTR pnKey) const
{
// Note pnKey==0 is acceptable, as the real key type could be an int
IRTLASSERT(m_pfnCalcKeyHash != NULL);
DWORD dwHash = (*m_pfnCalcKeyHash)(pnKey);
// We forcibly scramble the result to help ensure a better distribution
#ifndef __HASHFN_NO_NAMESPACE__
dwHash = HashFn::HashRandomizeBits(dwHash);
#else // !__HASHFN_NO_NAMESPACE__
dwHash = ::HashRandomizeBits(dwHash);
#endif // !__HASHFN_NO_NAMESPACE__
IRTLASSERT(dwHash != HASH_INVALID_SIGNATURE);
return dwHash;
}
// Use the key's hash signature to multiplex into a subtable
SubTable* _SubTable(DWORD dwSignature) const;
// Find the index of pst within the subtable array
int _SubTableIndex(SubTable* pst) const;
// Memory allocation wrappers to allow us to simulate allocation
// failures during testing
static SubTable** const
_AllocateSubTableArray(
size_t n);
static bool
_FreeSubTableArray(
SubTable** palht);
static SubTable* const
_AllocateSubTable(
LPCSTR pszName, // Identifies table for debugging
LKR_PFnExtractKey pfnExtractKey, // Extract key from record
LKR_PFnCalcKeyHash pfnCalcKeyHash, // Calculate hash signature of key
LKR_PFnEqualKeys pfnEqualKeys, // Compare two keys
LKR_PFnAddRefRecord pfnAddRefRecord,// AddRef in FindKey, etc
unsigned maxload, // Upperbound on avg chain length
DWORD initsize, // Initial size of hash table.
CLKRHashTable* phtParent, // Owning table.
bool fMultiKeys, // Allow multiple identical keys?
bool fNonPagedAllocs // use paged or NP pool in kernel
);
static bool
_FreeSubTable(
SubTable* plht);
public:
CLKRHashTable(
LPCSTR pszName, // Identifies table for debugging
LKR_PFnExtractKey pfnExtractKey, // Extract key from record
LKR_PFnCalcKeyHash pfnCalcKeyHash, // Calculate hash signature of key
LKR_PFnEqualKeys pfnEqualKeys, // Compare two keys
LKR_PFnAddRefRecord pfnAddRefRecord,// AddRef in FindKey, etc
unsigned maxload=LK_DFLT_MAXLOAD, // bound on avg chain length
DWORD initsize=LK_DFLT_INITSIZE,// Initial size of hash table.
DWORD num_subtbls=LK_DFLT_NUM_SUBTBLS, // #subordinate hash tables.
bool fMultiKeys=false // Allow multiple identical keys?
#ifdef LKRHASH_KERNEL_MODE
, bool fNonPagedAllocs=true // use paged or NP pool
#endif
);
~CLKRHashTable();
static const TCHAR* ClassName()
{return _TEXT("CLKRHashTable");}
int NumSubTables() const {return m_cSubTables;}
bool MultiKeys() const;
#ifdef LKRHASH_KERNEL_MODE
bool NonPagedAllocs() const;
#endif
static LK_TABLESIZE NumSubTables(DWORD& rinitsize, DWORD& rnum_subtbls);
// Thin wrappers for the corresponding methods in CLKRLinearHashTable
LK_RETCODE InsertRecord(const void* pvRecord, bool fOverwrite=false);
LK_RETCODE DeleteKey(const DWORD_PTR pnKey, bool fDeleteAllSame=false);
LK_RETCODE DeleteRecord(const void* pvRecord);
LK_RETCODE FindKey(const DWORD_PTR pnKey,
const void** ppvRecord) const;
LK_RETCODE FindRecord(const void* pvRecord) const;
#ifdef LKR_APPLY_IF
DWORD Apply(LKR_PFnRecordAction pfnAction,
void* pvState=NULL,
LK_LOCKTYPE lkl=LKL_READLOCK);
DWORD ApplyIf(LKR_PFnRecordPred pfnPredicate,
LKR_PFnRecordAction pfnAction,
void* pvState=NULL,
LK_LOCKTYPE lkl=LKL_READLOCK);
DWORD DeleteIf(LKR_PFnRecordPred pfnPredicate,
void* pvState=NULL);
#endif // LKR_APPLY_IF
void Clear();
int CheckTable() const;
DWORD Size() const;
DWORD MaxSize() const;
CLKRHashTableStats GetStatistics() const;
bool IsValid() const;
void SetTableLockSpinCount(WORD wSpins);
WORD GetTableLockSpinCount() const;
void SetBucketLockSpinCount(WORD wSpins);
WORD GetBucketLockSpinCount() const;
enum {
SIGNATURE = (('L') | ('K' << 8) | ('H' << 16) | ('T' << 24)),
SIGNATURE_FREE = (('L') | ('K' << 8) | ('H' << 16) | ('x' << 24)),
};
bool
ValidSignature() const
{ return m_dwSignature == SIGNATURE;}
// Is the hash table usable?
bool IsUsable() const
{ return (m_lkrcState == LK_SUCCESS); }
#ifdef LKR_EXPOSED_TABLE_LOCK
public:
#else // !LKR_EXPOSED_TABLE_LOCK
protected:
#endif // !LKR_EXPOSED_TABLE_LOCK
void WriteLock();
void ReadLock() const;
void WriteUnlock();
void ReadUnlock() const;
bool IsWriteLocked() const;
bool IsReadLocked() const;
bool IsWriteUnlocked() const;
bool IsReadUnlocked() const;
void ConvertSharedToExclusive();
void ConvertExclusiveToShared() const;
#ifdef LKRHASH_KERNEL_MODE
LKRHASH_ALLOCATOR_DEFINITIONS(CLKRHashTable);
#endif // LKRHASH_KERNEL_MODE
#ifdef LKR_DEPRECATED_ITERATORS
public:
typedef SubTable::CIterator CLHTIterator;
class CIterator : public CLHTIterator
{
protected:
friend class CLKRHashTable;
CLKRHashTable* m_pht; // which hash table?
int m_ist; // which subtable
private:
// Private copy ctor and op= to prevent compiler synthesizing them.
// Must provide (bad) implementation because we export instantiations.
CIterator(const CIterator&) {*(BYTE*)NULL;}
CIterator& operator=(const CIterator&) {return *(CIterator*)NULL;}
public:
CIterator(
LK_LOCKTYPE lkl=LKL_WRITELOCK)
: CLHTIterator(lkl),
m_pht(NULL),
m_ist(-1)
{}
const void* Record() const
{
IRTLASSERT(IsValid());
// This is a hack to work around a compiler bug. Calling
// CLHTIterator::Record calls this function recursively until
// the stack overflows.
const CLHTIterator* pBase = static_cast<const CLHTIterator*>(this);
return pBase->Record();
}
const DWORD_PTR Key() const
{
IRTLASSERT(IsValid());
const CLHTIterator* pBase = static_cast<const CLHTIterator*>(this);
return pBase->Key();
}
bool IsValid() const
{
const CLHTIterator* pBase = static_cast<const CLHTIterator*>(this);
return (m_pht != NULL && m_ist >= 0 && pBase->IsValid());
}
};
// Const iterators for readonly access
class CConstIterator : public CIterator
{
private:
// Private, unimplemented copy ctor and op= to prevent
// compiler synthesizing them.
CConstIterator(const CConstIterator&);
CConstIterator& operator=(const CConstIterator&);
public:
CConstIterator()
: CIterator(LKL_READLOCK)
{}
};
public:
LK_RETCODE InitializeIterator(CIterator* piter);
LK_RETCODE IncrementIterator(CIterator* piter);
LK_RETCODE CloseIterator(CIterator* piter);
LK_RETCODE InitializeIterator(CConstIterator* piter) const
{
IRTLASSERT(piter != NULL && piter->m_pht == NULL);
IRTLASSERT(piter->m_lkl != LKL_WRITELOCK);
if (piter == NULL || piter->m_pht != NULL
|| piter->m_lkl == LKL_WRITELOCK)
return LK_BAD_ITERATOR;
return const_cast<CLKRHashTable*>(this)
->InitializeIterator(static_cast<CIterator*>(piter));
}
LK_RETCODE IncrementIterator(CConstIterator* piter) const
{
IRTLASSERT(piter != NULL && piter->m_pht == this);
IRTLASSERT(piter->m_lkl != LKL_WRITELOCK);
if (piter == NULL || piter->m_pht != this
|| piter->m_lkl == LKL_WRITELOCK)
return LK_BAD_ITERATOR;
return const_cast<CLKRHashTable*>(this)
->IncrementIterator(static_cast<CIterator*>(piter));
}
LK_RETCODE CloseIterator(CConstIterator* piter) const
{
IRTLASSERT(piter != NULL && piter->m_pht == this);
IRTLASSERT(piter->m_lkl != LKL_WRITELOCK);
if (piter == NULL || piter->m_pht != this
|| piter->m_lkl == LKL_WRITELOCK)
return LK_BAD_ITERATOR;
return const_cast<CLKRHashTable*>(this)
->CloseIterator(static_cast<CIterator*>(piter));
};
#endif // LKR_DEPRECATED_ITERATORS
#ifdef LKR_STL_ITERATORS
private:
bool _IsValidIterator(const Iterator& riter) const
{
LKR_ITER_TRACE(_TEXT(" LKHT:_IsValidIterator(%p)\n"), &riter);
bool fValid = (riter.m_pht == this);
IRTLASSERT(fValid);
fValid = fValid && (0 <= riter.m_ist
&& riter.m_ist < (int) m_cSubTables);
IRTLASSERT(fValid);
IRTLASSERT(_SubTableIndex(riter.m_subiter.m_plht) == riter.m_ist);
fValid = fValid && riter.IsValid();
IRTLASSERT(fValid);
return fValid;
}
public:
Iterator
Begin();
Iterator
End() const
{
LKR_ITER_TRACE(_TEXT(" LKHT::End\n"));
return Iterator();
}
bool
Insert(
/* in */ const void* pvRecord,
/* out */ Iterator& riterResult,
/* in */ bool fOverwrite=false);
bool
Erase(
/* in,out */ Iterator& riter);
bool
Erase(
/*in*/ Iterator& riterFirst,
/*in*/ Iterator& riterLast);
bool
Find(
/* in */ DWORD_PTR pnKey,
/* out */ Iterator& riterResult);
bool
EqualRange(
/* in */ DWORD_PTR pnKey,
/* out */ Iterator& riterFirst, // inclusive
/* out */ Iterator& riterLast); // exclusive
#endif // LKR_STL_ITERATORS
}; // class CLKRHashTable
//--------------------------------------------------------------------
// A typesafe wrapper for CLKRHashTable (or CLKRLinearHashTable).
//
// * _Derived must derive from CTypedHashTable and provide certain member
// functions (ExtractKey, CalcKeyHash, EqualKeys, AddRefRecord). It's
// needed so that the method wrappers can downcast to the typesafe
// implementations that you provide.
// * _Record is the type of the record. C{Linear}HashTable will store
// >pointers< to _Record; i.e., stores _Records by reference, not by value.
// * _Key is the type of the key. _Key is used directly---it is not
// assumed to be a pointer type. _Key can be an integer or a pointer.
// C{Linear}HashTable assumes that the key is stored in the associated
// record. See the comments at the declaration of LKR_PFnExtractKey
// for more details.
// (optional parameters):
// * _BaseHashTable is the base hash table: CLKRHashTable or
/// CLKRLinearHashTable
// * _BaseIterator is the iterator type, _BaseHashTable::CIterator
//
// Some associative containers allow you to store key-value (aka
// name-value) pairs. LKRhash doesn't allow you to do this directly, but
// it's straightforward to build a simple wrapper class (or to use
// std::pair<key,value>).
//
// CTypedHashTable could derive directly from CLKRLinearHashTable, if you
// don't need the extra overhead of CLKRHashTable (which is quite low).
// If you expect to be using the table a lot on multiprocessor machines,
// you should use the default of CLKRHashTable, as it will scale better.
//
// You may need to add the following line to your code to disable
// warning messages about truncating extremly long identifiers.
// #pragma warning (disable : 4786)
//
// The _Derived class should look something like this:
// class CDerived : public CTypedHashTable<CDerived, RecordType, KeyType>
// {
// public:
// CDerived()
// : CTypedHashTable<CDerived, RecordType, KeyType>("DerivedTable")
// { /* other ctor actions, if needed */ }
// static KeyType ExtractKey(const RecordType* pTest);
// static DWORD CalcKeyHash(const KeyType Key);
// static bool EqualKeys(const KeyType Key1, const KeyType Key2);
// static void AddRefRecord(RecordType* pRecord,LK_ADDREF_REASON lkar);
// // You probably want to declare the copy ctor and operator=
// // as private, so that the compiler won't synthesize them.
// // You don't need to provide a dtor, unless you have custom
// // member data to clean up.
//
// // Optional: other functions
// };
//
//--------------------------------------------------------------------
template < class _Derived, class _Record, class _Key,
class _BaseHashTable=CLKRHashTable
#ifdef LKR_DEPRECATED_ITERATORS
, class _BaseIterator=_BaseHashTable::CIterator
#endif // LKR_DEPRECATED_ITERATORS
>
class CTypedHashTable : public _BaseHashTable
{
public:
// convenient aliases
typedef _Derived Derived;
typedef _Record Record;
typedef _Key Key;
typedef _BaseHashTable BaseHashTable;
typedef CTypedHashTable<_Derived, _Record, _Key, _BaseHashTable
#ifdef LKR_DEPRECATED_ITERATORS
, _BaseIterator
#endif // LKR_DEPRECATED_ITERATORS
> HashTable;
#ifdef LKR_DEPRECATED_ITERATORS
typedef _BaseIterator BaseIterator;
#endif // LKR_DEPRECATED_ITERATORS
#ifdef LKR_APPLY_IF
// ApplyIf() and DeleteIf(): Does the record match the predicate?
// Note: takes a Record*, not a const Record*. You can modify the
// record in Pred() or Action(), if you like, but if you do, you
// should use LKL_WRITELOCK to lock the table.
typedef LK_PREDICATE (WINAPI *PFnRecordPred) (Record* pRec, void* pvState);
// Apply() et al: Perform action on record.
typedef LK_ACTION (WINAPI *PFnRecordAction)(Record* pRec, void* pvState);
#endif // LKR_APPLY_IF
private:
// Wrappers for the typesafe methods exposed by the derived class
static const DWORD_PTR WINAPI
_ExtractKey(const void* pvRecord)
{
const _Record* pRec = static_cast<const _Record*>(pvRecord);
const _Key key = static_cast<const _Key>(_Derived::ExtractKey(pRec));
// I would prefer to use reinterpret_cast here and in _CalcKeyHash
// and _EqualKeys, but the stupid Win64 compiler thinks it knows
// better than I do.
return (const DWORD_PTR) key;
}
static DWORD WINAPI
_CalcKeyHash(const DWORD_PTR pnKey)
{
const _Key key = (const _Key) (DWORD_PTR) pnKey;
return _Derived::CalcKeyHash(key);
}
static BOOL WINAPI
_EqualKeys(const DWORD_PTR pnKey1, const DWORD_PTR pnKey2)
{
const _Key key1 = (const _Key) (DWORD_PTR) pnKey1;
const _Key key2 = (const _Key) (DWORD_PTR) pnKey2;
return _Derived::EqualKeys(key1, key2);
}
static void WINAPI
_AddRefRecord(const void* pvRecord, LK_ADDREF_REASON lkar)
{
_Record* pRec = static_cast<_Record*>(const_cast<void*>(pvRecord));
_Derived::AddRefRecord(pRec, lkar);
}
#ifdef LKR_APPLY_IF
// Typesafe wrappers for Apply, ApplyIf, and DeleteIf.
class CState
{
public:
PFnRecordPred m_pfnPred;
PFnRecordAction m_pfnAction;
void* m_pvState;
CState(
PFnRecordPred pfnPred,
PFnRecordAction pfnAction,
void* pvState)
: m_pfnPred(pfnPred), m_pfnAction(pfnAction), m_pvState(pvState)
{}
};
static LK_PREDICATE WINAPI
_Pred(const void* pvRecord, void* pvState)
{
_Record* pRec = static_cast<_Record*>(const_cast<void*>(pvRecord));
CState* pState = static_cast<CState*>(pvState);
return (*pState->m_pfnPred)(pRec, pState->m_pvState);
}
static LK_ACTION WINAPI
_Action(const void* pvRecord, void* pvState)
{
_Record* pRec = static_cast<_Record*>(const_cast<void*>(pvRecord));
CState* pState = static_cast<CState*>(pvState);
return (*pState->m_pfnAction)(pRec, pState->m_pvState);
}
#endif // LKR_APPLY_IF
public:
CTypedHashTable(
LPCSTR pszName, // Identifies table for debugging
unsigned maxload=LK_DFLT_MAXLOAD, // Upperbound on avg chain len
DWORD initsize=LK_DFLT_INITSIZE, // Initial size of table: S/M/L
DWORD num_subtbls=LK_DFLT_NUM_SUBTBLS,// #subordinate hash tables.
bool fMultiKeys=false // Allow multiple identical keys?
#ifdef LKRHASH_KERNEL_MODE
, bool fNonPagedAllocs=true // use paged or NP pool in kernel
#endif
)
: _BaseHashTable(pszName, _ExtractKey, _CalcKeyHash, _EqualKeys,
_AddRefRecord, maxload, initsize, num_subtbls,
fMultiKeys
#ifdef LKRHASH_KERNEL_MODE
, fNonPagedAllocs
#endif
)
{}
LK_RETCODE InsertRecord(const _Record* pRec, bool fOverwrite=false)
{ return _BaseHashTable::InsertRecord(pRec, fOverwrite); }
LK_RETCODE DeleteKey(const _Key key, bool fDeleteAllSame=false)
{
const void* pvKey = reinterpret_cast<const void*>((DWORD_PTR)(key));
DWORD_PTR pnKey = reinterpret_cast<DWORD_PTR>(pvKey);
return _BaseHashTable::DeleteKey(pnKey, fDeleteAllSame);
}
LK_RETCODE DeleteRecord(const _Record* pRec)
{ return _BaseHashTable::DeleteRecord(pRec); }
// Note: returns a _Record**, not a const Record**. Note that you
// can use a const type for the template parameter to ensure constness.
LK_RETCODE FindKey(const _Key key, _Record** ppRec) const
{
if (ppRec == NULL)
return LK_BAD_RECORD;
*ppRec = NULL;
const void* pvRec = NULL;
const void* pvKey = reinterpret_cast<const void*>((DWORD_PTR)(key));
DWORD_PTR pnKey = reinterpret_cast<DWORD_PTR>(pvKey);
LK_RETCODE lkrc = _BaseHashTable::FindKey(pnKey, &pvRec);
*ppRec = static_cast<_Record*>(const_cast<void*>(pvRec));
return lkrc;
}
LK_RETCODE FindRecord(const _Record* pRec) const
{ return _BaseHashTable::FindRecord(pRec); }
// Other C{Linear}HashTable methods can be exposed without change
#ifdef LKR_APPLY_IF
public:
// Typesafe wrappers for Apply et al
DWORD Apply(PFnRecordAction pfnAction,
void* pvState=NULL,
LK_LOCKTYPE lkl=LKL_READLOCK)
{
IRTLASSERT(pfnAction != NULL);
if (pfnAction == NULL)
return 0;
CState state(NULL, pfnAction, pvState);
return _BaseHashTable::Apply(_Action, &state, lkl);
}
DWORD ApplyIf(PFnRecordPred pfnPredicate,
PFnRecordAction pfnAction,
void* pvState=NULL,
LK_LOCKTYPE lkl=LKL_READLOCK)
{
IRTLASSERT(pfnPredicate != NULL && pfnAction != NULL);
if (pfnPredicate == NULL || pfnAction == NULL)
return 0;
CState state(pfnPredicate, pfnAction, pvState);
return _BaseHashTable::ApplyIf(_Pred, _Action, &state, lkl);
}
DWORD DeleteIf(PFnRecordPred pfnPredicate, void* pvState=NULL)
{
IRTLASSERT(pfnPredicate != NULL);
if (pfnPredicate == NULL)
return 0;
CState state(pfnPredicate, NULL, pvState);
return _BaseHashTable::DeleteIf(_Pred, &state);
}
#endif // LKR_APPLY_IF
#ifdef LKR_DEPRECATED_ITERATORS
// Typesafe wrappers for iterators
class CIterator : public _BaseIterator
{
private:
// Private, unimplemented copy ctor and op= to prevent
// compiler synthesizing them.
CIterator(const CIterator&);
CIterator& operator=(const CIterator&);
public:
CIterator(
LK_LOCKTYPE lkl=LKL_WRITELOCK)
: _BaseIterator(lkl)
{}
_Record* Record() const
{
const _BaseIterator* pBase = static_cast<const _BaseIterator*>(this);
return reinterpret_cast<_Record*>(const_cast<void*>(
pBase->Record()));
}
_Key Key() const
{
const _BaseIterator* pBase = static_cast<const _BaseIterator*>(this);
return reinterpret_cast<_Key>(reinterpret_cast<void*>(pBase->Key()));
}
};
// readonly iterator
class CConstIterator : public CIterator
{
private:
// Private, unimplemented copy ctor and op= to prevent
// compiler synthesizing them.
CConstIterator(const CConstIterator&);
CConstIterator& operator=(const CConstIterator&);
public:
CConstIterator()
: CIterator(LKL_READLOCK)
{}
const _Record* Record() const
{
return CIterator::Record();
}
const _Key Key() const
{
return CIterator::Key();
}
};
public:
LK_RETCODE InitializeIterator(CIterator* piter)
{
return _BaseHashTable::InitializeIterator(piter);
}
LK_RETCODE IncrementIterator(CIterator* piter)
{
return _BaseHashTable::IncrementIterator(piter);
}
LK_RETCODE CloseIterator(CIterator* piter)
{
return _BaseHashTable::CloseIterator(piter);
}
LK_RETCODE InitializeIterator(CConstIterator* piter) const
{
return const_cast<HashTable*>(this)
->InitializeIterator(static_cast<CIterator*>(piter));
}
LK_RETCODE IncrementIterator(CConstIterator* piter) const
{
return const_cast<HashTable*>(this)
->IncrementIterator(static_cast<CIterator*>(piter));
}
LK_RETCODE CloseIterator(CConstIterator* piter) const
{
return const_cast<HashTable*>(this)
->CloseIterator(static_cast<CIterator*>(piter));
}
#endif // LKR_DEPRECATED_ITERATORS
#ifdef LKR_STL_ITERATORS
// TODO: const_iterator
public:
class iterator
{
friend class CTypedHashTable<_Derived, _Record, _Key,
_BaseHashTable
#ifdef LKR_DEPRECATED_ITERATORS
, _BaseIterator
#endif // LKR_DEPRECATED_ITERATORS
>;
protected:
_BaseHashTable::Iterator m_iter;
iterator(
_BaseHashTable::Iterator& rhs)
: m_iter(rhs)
{
LKR_ITER_TRACE(_TEXT("Typed::prot ctor, this=%p, rhs=%p\n"),
this, &rhs);
}
public:
typedef std::forward_iterator_tag iterator_category;
typedef _Record value_type;
typedef ptrdiff_t difference_type;
typedef size_t size_type;
typedef value_type& reference;
typedef value_type* pointer;
iterator()
: m_iter()
{
LKR_ITER_TRACE(_TEXT("Typed::default ctor, this=%p\n"), this);
}
iterator(
const iterator& rhs)
: m_iter(rhs.m_iter)
{
LKR_ITER_TRACE(_TEXT("Typed::copy ctor, this=%p, rhs=%p\n"),
this, &rhs);
}
iterator& operator=(
const iterator& rhs)
{
LKR_ITER_TRACE(_TEXT("Typed::operator=, this=%p, rhs=%p\n"),
this, &rhs);
m_iter = rhs.m_iter;
return *this;
}
~iterator()
{
LKR_ITER_TRACE(_TEXT("Typed::dtor, this=%p\n"), this);
}
reference operator*() const
{
void* pvRecord = const_cast<void*>(m_iter.Record());
return reinterpret_cast<reference>(pvRecord);
}
pointer operator->() const { return &(operator*()); }
// pre-increment
iterator& operator++()
{
LKR_ITER_TRACE(_TEXT("Typed::pre-increment, this=%p\n"), this);
m_iter.Increment();
return *this;
}
// post-increment
iterator operator++(int)
{
LKR_ITER_TRACE(_TEXT("Typed::post-increment, this=%p\n"), this);
iterator iterPrev = *this;
m_iter.Increment();
return iterPrev;
}
bool operator==(
const iterator& rhs) const
{
LKR_ITER_TRACE(_TEXT("Typed::operator==, this=%p, rhs=%p\n"),
this, &rhs);
return m_iter == rhs.m_iter;
}
bool operator!=(
const iterator& rhs) const
{
LKR_ITER_TRACE(_TEXT("Typed::operator!=, this=%p, rhs=%p\n"),
this, &rhs);
return m_iter != rhs.m_iter;
}
_Record* Record() const
{
LKR_ITER_TRACE(_TEXT("Typed::Record, this=%p\n"), this);
return reinterpret_cast<_Record*>(
const_cast<void*>(m_iter.Record()));
}
_Key Key() const
{
LKR_ITER_TRACE(_TEXT("Typed::Key, this=%p\n"), this);
return reinterpret_cast<_Key>(
reinterpret_cast<void*>(m_iter.Key()));
}
}; // class iterator
// Return iterator pointing to first item in table
iterator begin()
{
LKR_ITER_TRACE(_TEXT("Typed::begin()\n"));
return iterator(_BaseHashTable::Begin());
}
// Return a one-past-the-end iterator. Always empty.
iterator end() const
{
LKR_ITER_TRACE(_TEXT("Typed::end()\n"));
return iterator(_BaseHashTable::End());
}
template <class _InputIterator>
CTypedHashTable(
LPCSTR pszName, // An identifier for debugging
_InputIterator f, // first element in range
_InputIterator l, // one-beyond-last element
unsigned maxload=LK_DFLT_MAXLOAD, // Upperbound on avg chain len
DWORD initsize=LK_DFLT_INITSIZE, // Initial size of table: S/M/L
DWORD num_subtbls=LK_DFLT_NUM_SUBTBLS,// #subordinate hash tables.
bool fMultiKeys=false // Allow multiple identical keys?
#ifdef LKRHASH_KERNEL_MODE
, bool fNonPagedAllocs=true // use paged or NP pool in kernel
#endif
)
: _BaseHashTable(pszName, _ExtractKey, _CalcKeyHash, _EqualKeys,
_AddRefRecord, maxload, initsize, num_subtbls,
fMultiKeys
#ifdef LKRHASH_KERNEL_MODE
, fNonPagedAllocs
#endif
)
{
insert(f, l);
}
template <class _InputIterator>
void insert(_InputIterator f, _InputIterator l)
{
for ( ; f != l; ++f)
InsertRecord(&(*f));
}
bool
Insert(
const _Record* pRecord,
iterator& riterResult,
bool fOverwrite=false)
{
LKR_ITER_TRACE(_TEXT("Typed::Insert\n"));
return _BaseHashTable::Insert(pRecord, riterResult.m_iter, fOverwrite);
}
bool
Erase(
iterator& riter)
{
LKR_ITER_TRACE(_TEXT("Typed::Erase\n"));
return _BaseHashTable::Erase(riter.m_iter);
}
bool
Erase(
iterator& riterFirst,
iterator& riterLast)
{
LKR_ITER_TRACE(_TEXT("Typed::Erase2\n"));
return _BaseHashTable::Erase(riterFirst.m_iter, riterLast.m_iter);
}
bool
Find(
const _Key key,
iterator& riterResult)
{
LKR_ITER_TRACE(_TEXT("Typed::Find\n"));
const void* pvKey = reinterpret_cast<const void*>((DWORD_PTR)(key));
DWORD_PTR pnKey = reinterpret_cast<DWORD_PTR>(pvKey);
return _BaseHashTable::Find(pnKey, riterResult.m_iter);
}
bool
EqualRange(
const _Key key,
iterator& riterFirst,
iterator& riterLast)
{
LKR_ITER_TRACE(_TEXT("Typed::EqualRange\n"));
const void* pvKey = reinterpret_cast<const void*>((DWORD_PTR)(key));
DWORD_PTR pnKey = reinterpret_cast<DWORD_PTR>(pvKey);
return _BaseHashTable::EqualRange(pnKey, riterFirst.m_iter,
riterLast.m_iter);
}
// The iterator functions for an STL hash_(|multi)_(set|map)
//
// Value type of a Pair-Associative Container is
// pair<const key_type, mapped_type>
//
// pair<iterator,bool> insert(const value_type& x);
//
// void erase(iterator pos);
// void erase(iterator f, iterator l);
//
// iterator find(const key_type& k) [const];
// const_iterator find(const key_type& k) const;
//
// pair<iterator,iterator> equal_range(const key_type& k) [const];
// pair<const_iterator,const_iterator> equal_range(const key_type& k) const
#endif // LKR_STL_ITERATORS
}; // class CTypedHashTable
#ifndef __LKRHASH_NO_NAMESPACE__
};
#endif // !__LKRHASH_NO_NAMESPACE__
#endif // __LKRHASH_H__
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