gecko-dev/xpcom/ds/nsHashtable.h

358 lines
9.8 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/*
* The contents of this file are subject to the Netscape 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/NPL/
*
* 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 Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All
* Rights Reserved.
*
* Contributor(s):
* This Original Code has been modified by IBM Corporation.
* Modifications made by IBM described herein are
* Copyright (c) International Business Machines
* Corporation, 2000
*
* Modifications to Mozilla code or documentation
* identified per MPL Section 3.3
*
* Date Modified by Description of modification
* 04/20/2000 IBM Corp. Added PR_CALLBACK for Optlink use in OS2
*/
#ifndef nsHashtable_h__
#define nsHashtable_h__
#include "plhash.h"
#include "prlock.h"
#include "nsCom.h"
#include "nscore.h"
#include "nsString.h"
class nsHashtable;
class nsStringKey;
class NS_COM nsHashKey {
protected:
nsHashKey(void);
public:
virtual ~nsHashKey(void);
virtual PRUint32 HashCode(void) const = 0;
virtual PRBool Equals(const nsHashKey *aKey) const = 0;
virtual nsHashKey *Clone() const = 0;
#ifdef DEBUG
public:
// used for verification that we're casting to the correct key type
enum nsHashKeyType {
UnknownKey,
SupportsKey,
VoidKey,
IDKey,
CStringKey,
StringKey,
OpaqueKey
};
nsHashKeyType GetKeyType() const { return mKeyType; }
protected:
nsHashKeyType mKeyType;
#endif
};
// Enumerator callback function. Use
typedef PRBool (*PR_CALLBACK nsHashtableEnumFunc)(nsHashKey *aKey, void *aData, void* closure);
class NS_COM nsHashtable {
protected:
// members
PRLock* mLock;
PLHashTable mHashtable;
PRBool mEnumerating;
public:
nsHashtable(PRUint32 aSize = 16, PRBool threadSafe = PR_FALSE);
virtual ~nsHashtable();
PRInt32 Count(void) { return mHashtable.nentries; }
PRBool Exists(nsHashKey *aKey);
void *Put(nsHashKey *aKey, void *aData);
void *Get(nsHashKey *aKey);
void *Remove(nsHashKey *aKey);
nsHashtable *Clone();
void Enumerate(nsHashtableEnumFunc aEnumFunc, void* closure = NULL);
void Reset();
void Reset(nsHashtableEnumFunc destroyFunc, void* closure = NULL);
};
////////////////////////////////////////////////////////////////////////////////
// nsObjectHashtable: an nsHashtable where the elements are C++ objects to be
// deleted
typedef void* (*PR_CALLBACK nsHashtableCloneElementFunc)(nsHashKey *aKey, void *aData, void* closure);
class NS_COM nsObjectHashtable : public nsHashtable {
public:
nsObjectHashtable(nsHashtableCloneElementFunc cloneElementFun,
void* cloneElementClosure,
nsHashtableEnumFunc destroyElementFun,
void* destroyElementClosure,
PRUint32 aSize = 16, PRBool threadSafe = PR_FALSE);
~nsObjectHashtable();
nsHashtable *Clone();
void Reset();
PRBool RemoveAndDelete(nsHashKey *aKey);
protected:
static PRIntn PR_CALLBACK CopyElement(PLHashEntry *he, PRIntn i, void *arg);
nsHashtableCloneElementFunc mCloneElementFun;
void* mCloneElementClosure;
nsHashtableEnumFunc mDestroyElementFun;
void* mDestroyElementClosure;
};
////////////////////////////////////////////////////////////////////////////////
// nsSupportsHashtable: an nsHashtable where the elements are nsISupports*
class nsISupports;
class NS_COM nsSupportsHashtable
: private nsHashtable
{
public:
typedef PRBool (* PR_CALLBACK EnumFunc) (nsHashKey *aKey, void *aData, void* closure);
nsSupportsHashtable(PRUint32 aSize = 16, PRBool threadSafe = PR_FALSE)
: nsHashtable(aSize, threadSafe) {}
~nsSupportsHashtable();
PRInt32 Count (void)
{
return nsHashtable::Count();
}
PRBool Exists (nsHashKey *aKey)
{
return nsHashtable::Exists (aKey);
}
PRBool Put (nsHashKey *aKey,
nsISupports *aData,
nsISupports **value = nsnull);
nsISupports* Get (nsHashKey *aKey);
PRBool Remove (nsHashKey *aKey, nsISupports **value = nsnull);
nsHashtable *Clone();
void Enumerate (EnumFunc aEnumFunc, void* closure = NULL)
{
nsHashtable::Enumerate (aEnumFunc, closure);
}
void Reset();
private:
static PRBool PR_CALLBACK ReleaseElement (nsHashKey *, void *, void *);
static PRIntn PR_CALLBACK EnumerateCopy (PLHashEntry *, PRIntn, void *);
};
////////////////////////////////////////////////////////////////////////////////
// nsISupportsKey: Where keys are nsISupports objects that get refcounted.
#include "nsISupports.h"
class nsISupportsKey : public nsHashKey {
protected:
nsISupports* mKey;
public:
nsISupportsKey(nsISupports* key) {
#ifdef DEBUG
mKeyType = SupportsKey;
#endif
mKey = key;
NS_IF_ADDREF(mKey);
}
~nsISupportsKey(void) {
NS_IF_RELEASE(mKey);
}
PRUint32 HashCode(void) const {
return (PRUint32)mKey;
}
PRBool Equals(const nsHashKey *aKey) const {
NS_ASSERTION(aKey->GetKeyType() == SupportsKey, "mismatched key types");
return (mKey == ((nsISupportsKey *) aKey)->mKey);
}
nsHashKey *Clone() const {
return new nsISupportsKey(mKey);
}
};
////////////////////////////////////////////////////////////////////////////////
// nsVoidKey: Where keys are void* objects that don't get refcounted.
class nsVoidKey : public nsHashKey {
protected:
void* mKey;
public:
nsVoidKey(void* key) {
#ifdef DEBUG
mKeyType = VoidKey;
#endif
mKey = key;
}
PRUint32 HashCode(void) const {
return (PRUint32)mKey;
}
PRBool Equals(const nsHashKey *aKey) const {
NS_ASSERTION(aKey->GetKeyType() == VoidKey, "mismatched key types");
return (mKey == ((const nsVoidKey *) aKey)->mKey);
}
nsHashKey *Clone() const {
return new nsVoidKey(mKey);
}
void* GetValue() { return mKey; }
};
////////////////////////////////////////////////////////////////////////////////
// nsIDKey: Where keys are nsIDs (e.g. nsIID, nsCID).
#include "nsID.h"
class nsIDKey : public nsHashKey {
protected:
nsID mID;
public:
nsIDKey(const nsID &aID) {
#ifdef DEBUG
mKeyType = IDKey;
#endif
mID = aID;
}
PRUint32 HashCode(void) const {
return mID.m0;
}
PRBool Equals(const nsHashKey *aKey) const {
NS_ASSERTION(aKey->GetKeyType() == IDKey, "mismatched key types");
return (mID.Equals(((const nsIDKey *) aKey)->mID));
}
nsHashKey *Clone() const {
return new nsIDKey(mID);
}
};
////////////////////////////////////////////////////////////////////////////////
#include "nsString.h"
// for null-terminated c-strings
class NS_COM nsCStringKey : public nsHashKey {
public:
enum Ownership {
NEVER_OWN, // 'str' is very long lived, even clones don't need to copy it.
OWN_CLONE, // 'str' is as long lived as this key. But clones make a copy.
OWN // 'str' to be free'd in key dtor. Clones make their own copy.
};
nsCStringKey(const char* str, PRInt32 strLen = -1, Ownership own = OWN_CLONE);
nsCStringKey(const nsCString& str);
~nsCStringKey(void);
PRUint32 HashCode(void) const;
PRBool Equals(const nsHashKey* aKey) const;
nsHashKey* Clone() const;
// For when the owner of the hashtable wants to peek at the actual
// string in the key. No copy is made, so be careful.
const char* GetString() const { return mStr; }
PRUint32 GetStringLength() const { return mStrLen; }
protected:
char* mStr;
PRUint32 mStrLen;
Ownership mOwnership;
};
// for null-terminated unicode strings
class NS_COM nsStringKey : public nsHashKey {
public:
enum Ownership {
NEVER_OWN, // 'str' is very long lived, even clones don't need to copy it.
OWN_CLONE, // 'str' is as long lived as this key. But clones make a copy.
OWN // 'str' to be free'd in key dtor. Clones make their own copy.
};
nsStringKey(const PRUnichar* str, PRInt32 strLen = -1, Ownership own = OWN_CLONE);
nsStringKey(const nsAReadableString& str);
~nsStringKey(void);
PRUint32 HashCode(void) const;
PRBool Equals(const nsHashKey* aKey) const;
nsHashKey* Clone() const;
// For when the owner of the hashtable wants to peek at the actual
// string in the key. No copy is made, so be careful.
const PRUnichar* GetString() const { return mStr; }
PRUint32 GetStringLength() const { return mStrLen; }
protected:
PRUnichar* mStr;
PRUint32 mStrLen;
Ownership mOwnership;
};
// for opaque buffers of data which may contain nulls
class NS_COM nsOpaqueKey : public nsHashKey {
public:
enum Ownership {
NEVER_OWN, // 'buf' is very long lived, even clones don't need to copy it.
OWN_CLONE, // 'buf' is as long lived as this key. But clones make a copy.
OWN // 'buf' to be free'd in key dtor. Clones make their own copy.
};
nsOpaqueKey(const char* buf, PRUint32 bufLen, Ownership own = OWN_CLONE);
~nsOpaqueKey(void);
PRUint32 HashCode(void) const;
PRBool Equals(const nsHashKey* aKey) const;
nsHashKey* Clone() const;
// For when the owner of the hashtable wants to peek at the actual
// string in the key. No copy is made, so be careful.
const char* GetBuffer() const { return mBuf; }
PRUint32 GetBufferLength() const { return mBufLen; }
protected:
char* mBuf;
PRUint32 mBufLen;
Ownership mOwnership;
};
////////////////////////////////////////////////////////////////////////////////
#endif