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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef nsTHashKeys_h__
#define nsTHashKeys_h__
#include "nsID.h"
#include "nsISupports.h"
#include "nsCOMPtr.h"
#include "PLDHashTable.h"
#include <new>
#include "nsString.h"
#include "nsCRTGlue.h"
#include "nsUnicharUtils.h"
#include "nsPointerHashKeys.h"
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <type_traits>
#include <utility>
#include "mozilla/HashFunctions.h"
namespace mozilla {
// These are defined analogously to the HashString overloads in mfbt.
inline uint32_t HashString(const nsAString& aStr) {
return HashString(aStr.BeginReading(), aStr.Length());
}
inline uint32_t HashString(const nsACString& aStr) {
return HashString(aStr.BeginReading(), aStr.Length());
}
} // namespace mozilla
/** @file nsHashKeys.h
* standard HashKey classes for nsBaseHashtable and relatives. Each of these
* classes follows the nsTHashtable::EntryType specification
*
* Lightweight keytypes provided here:
* nsStringHashKey
* nsCStringHashKey
* nsUint32HashKey
* nsUint64HashKey
* nsFloatHashKey
* IntPtrHashKey
* nsPtrHashKey
* nsVoidPtrHashKey
* nsISupportsHashKey
* nsIDHashKey
* nsDepCharHashKey
* nsCharPtrHashKey
* nsUnicharPtrHashKey
* nsGenericHashKey
*/
/**
* hashkey wrapper using nsAString KeyType
*
* @see nsTHashtable::EntryType for specification
*/
class nsStringHashKey : public PLDHashEntryHdr {
public:
typedef const nsAString& KeyType;
typedef const nsAString* KeyTypePointer;
explicit nsStringHashKey(KeyTypePointer aStr) : mStr(*aStr) {}
nsStringHashKey(const nsStringHashKey&) = delete;
nsStringHashKey(nsStringHashKey&& aToMove)
: PLDHashEntryHdr(std::move(aToMove)), mStr(std::move(aToMove.mStr)) {}
~nsStringHashKey() = default;
KeyType GetKey() const { return mStr; }
bool KeyEquals(const KeyTypePointer aKey) const { return mStr.Equals(*aKey); }
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(const KeyTypePointer aKey) {
return mozilla::HashString(*aKey);
}
#ifdef MOZILLA_INTERNAL_API
// To avoid double-counting, only measure the string if it is unshared.
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
return GetKey().SizeOfExcludingThisIfUnshared(aMallocSizeOf);
}
#endif
enum { ALLOW_MEMMOVE = true };
private:
nsString mStr;
};
#ifdef MOZILLA_INTERNAL_API
namespace mozilla::detail {
template <class CharT, bool Unicode = true>
struct comparatorTraits {};
template <>
struct comparatorTraits<char, false> {
static int caseInsensitiveCompare(const char* aLhs, const char* aRhs,
size_t aLhsLength, size_t aRhsLength) {
return nsCaseInsensitiveCStringComparator(aLhs, aRhs, aLhsLength,
aRhsLength);
};
};
template <>
struct comparatorTraits<char, true> {
static int caseInsensitiveCompare(const char* aLhs, const char* aRhs,
size_t aLhsLength, size_t aRhsLength) {
return nsCaseInsensitiveUTF8StringComparator(aLhs, aRhs, aLhsLength,
aRhsLength);
};
};
template <>
struct comparatorTraits<char16_t, true> {
static int caseInsensitiveCompare(const char16_t* aLhs, const char16_t* aRhs,
size_t aLhsLength, size_t aRhsLength) {
return nsCaseInsensitiveStringComparator(aLhs, aRhs, aLhsLength,
aRhsLength);
};
};
} // namespace mozilla::detail
/**
* This is internal-API only because nsCaseInsensitive{C}StringComparator is
* internal-only.
*
* @see nsTHashtable::EntryType for specification
*/
template <typename T, bool Unicode>
class nsTStringCaseInsensitiveHashKey : public PLDHashEntryHdr {
public:
typedef const nsTSubstring<T>& KeyType;
typedef const nsTSubstring<T>* KeyTypePointer;
explicit nsTStringCaseInsensitiveHashKey(KeyTypePointer aStr) : mStr(*aStr) {
// take it easy just deal HashKey
}
nsTStringCaseInsensitiveHashKey(const nsTStringCaseInsensitiveHashKey&) =
delete;
nsTStringCaseInsensitiveHashKey(nsTStringCaseInsensitiveHashKey&& aToMove)
: PLDHashEntryHdr(std::move(aToMove)), mStr(std::move(aToMove.mStr)) {}
~nsTStringCaseInsensitiveHashKey() = default;
KeyType GetKey() const { return mStr; }
bool KeyEquals(const KeyTypePointer aKey) const {
using comparator = typename mozilla::detail::comparatorTraits<T, Unicode>;
return mStr.Equals(*aKey, comparator::caseInsensitiveCompare);
}
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(const KeyTypePointer aKey) {
nsTAutoString<T> tmKey(*aKey);
ToLowerCase(tmKey);
return mozilla::HashString(tmKey);
}
enum { ALLOW_MEMMOVE = true };
// To avoid double-counting, only measure the string if it is unshared.
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
return GetKey().SizeOfExcludingThisIfUnshared(aMallocSizeOf);
}
private:
const nsTString<T> mStr;
};
using nsStringCaseInsensitiveHashKey =
nsTStringCaseInsensitiveHashKey<char16_t, true>;
using nsCStringASCIICaseInsensitiveHashKey =
nsTStringCaseInsensitiveHashKey<char, false>;
using nsCStringUTF8CaseInsensitiveHashKey =
nsTStringCaseInsensitiveHashKey<char, true>;
#endif // MOZILLA_INTERNAL_API
/**
* hashkey wrapper using nsACString KeyType
*
* @see nsTHashtable::EntryType for specification
*/
class nsCStringHashKey : public PLDHashEntryHdr {
public:
typedef const nsACString& KeyType;
typedef const nsACString* KeyTypePointer;
explicit nsCStringHashKey(const nsACString* aStr) : mStr(*aStr) {}
nsCStringHashKey(nsCStringHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mStr(std::move(aOther.mStr)) {}
~nsCStringHashKey() = default;
KeyType GetKey() const { return mStr; }
bool KeyEquals(KeyTypePointer aKey) const { return mStr.Equals(*aKey); }
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return mozilla::HashString(*aKey);
}
#ifdef MOZILLA_INTERNAL_API
// To avoid double-counting, only measure the string if it is unshared.
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
return GetKey().SizeOfExcludingThisIfUnshared(aMallocSizeOf);
}
#endif
enum { ALLOW_MEMMOVE = true };
private:
const nsCString mStr;
};
/**
* hashkey wrapper using integral or enum KeyTypes
*
* @see nsTHashtable::EntryType for specification
*/
template <typename T,
std::enable_if_t<std::is_integral_v<T> || std::is_enum_v<T>, int> = 0>
class nsIntegralHashKey : public PLDHashEntryHdr {
public:
using KeyType = const T&;
using KeyTypePointer = const T*;
explicit nsIntegralHashKey(KeyTypePointer aKey) : mValue(*aKey) {}
nsIntegralHashKey(nsIntegralHashKey&& aOther) noexcept
: PLDHashEntryHdr(std::move(aOther)), mValue(aOther.mValue) {}
~nsIntegralHashKey() = default;
KeyType GetKey() const { return mValue; }
bool KeyEquals(KeyTypePointer aKey) const { return *aKey == mValue; }
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return mozilla::HashGeneric(*aKey);
}
enum { ALLOW_MEMMOVE = true };
private:
const T mValue;
};
/**
* hashkey wrapper using uint32_t KeyType
*
* @see nsTHashtable::EntryType for specification
*/
using nsUint32HashKey = nsIntegralHashKey<uint32_t>;
/**
* hashkey wrapper using uint64_t KeyType
*
* @see nsTHashtable::EntryType for specification
*/
using nsUint64HashKey = nsIntegralHashKey<uint64_t>;
/**
* hashkey wrapper using float KeyType
*
* @see nsTHashtable::EntryType for specification
*/
class nsFloatHashKey : public PLDHashEntryHdr {
public:
typedef const float& KeyType;
typedef const float* KeyTypePointer;
explicit nsFloatHashKey(KeyTypePointer aKey) : mValue(*aKey) {}
nsFloatHashKey(nsFloatHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mValue(std::move(aOther.mValue)) {}
~nsFloatHashKey() = default;
KeyType GetKey() const { return mValue; }
bool KeyEquals(KeyTypePointer aKey) const { return *aKey == mValue; }
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return *reinterpret_cast<const uint32_t*>(aKey);
}
enum { ALLOW_MEMMOVE = true };
private:
const float mValue;
};
/**
* hashkey wrapper using intptr_t KeyType
*
* @see nsTHashtable::EntryType for specification
*/
using IntPtrHashKey = nsIntegralHashKey<intptr_t>;
/**
* hashkey wrapper using nsISupports* KeyType
*
* @see nsTHashtable::EntryType for specification
*/
class nsISupportsHashKey : public PLDHashEntryHdr {
public:
using KeyType = nsISupports*;
using KeyTypePointer = const nsISupports*;
explicit nsISupportsHashKey(const nsISupports* aKey)
: mSupports(const_cast<nsISupports*>(aKey)) {}
nsISupportsHashKey(nsISupportsHashKey&& aOther) = default;
~nsISupportsHashKey() = default;
KeyType GetKey() const { return mSupports; }
bool KeyEquals(KeyTypePointer aKey) const { return aKey == mSupports; }
static KeyTypePointer KeyToPointer(KeyType aKey) { return aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return mozilla::HashGeneric(aKey);
}
enum { ALLOW_MEMMOVE = true };
private:
nsCOMPtr<nsISupports> mSupports;
};
/**
* hashkey wrapper using refcounted * KeyType
*
* @see nsTHashtable::EntryType for specification
*/
template <class T>
class nsRefPtrHashKey : public PLDHashEntryHdr {
public:
using KeyType = T*;
using KeyTypePointer = const T*;
explicit nsRefPtrHashKey(const T* aKey) : mKey(const_cast<T*>(aKey)) {}
nsRefPtrHashKey(nsRefPtrHashKey&& aOther) = default;
~nsRefPtrHashKey() = default;
KeyType GetKey() const { return mKey; }
bool KeyEquals(KeyTypePointer aKey) const { return aKey == mKey; }
static KeyTypePointer KeyToPointer(KeyType aKey) { return aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return mozilla::HashGeneric(aKey);
}
enum { ALLOW_MEMMOVE = true };
private:
RefPtr<T> mKey;
};
template <class T>
inline void ImplCycleCollectionTraverse(
nsCycleCollectionTraversalCallback& aCallback, nsRefPtrHashKey<T>& aField,
const char* aName, uint32_t aFlags = 0) {
CycleCollectionNoteChild(aCallback, aField.GetKey(), aName, aFlags);
}
/**
* hashkey wrapper using a function pointer KeyType
*
* @see nsTHashtable::EntryType for specification
*/
template <class T>
class nsFuncPtrHashKey : public PLDHashEntryHdr {
public:
typedef T& KeyType;
typedef const T* KeyTypePointer;
explicit nsFuncPtrHashKey(const T* aKey) : mKey(*const_cast<T*>(aKey)) {}
nsFuncPtrHashKey(const nsFuncPtrHashKey<T>& aToCopy) : mKey(aToCopy.mKey) {}
~nsFuncPtrHashKey() = default;
KeyType GetKey() const { return const_cast<T&>(mKey); }
bool KeyEquals(KeyTypePointer aKey) const { return *aKey == mKey; }
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return mozilla::HashGeneric(*aKey);
}
enum { ALLOW_MEMMOVE = true };
protected:
T mKey;
};
/**
* hashkey wrapper using nsID KeyType
*
* @see nsTHashtable::EntryType for specification
*/
class nsIDHashKey : public PLDHashEntryHdr {
public:
typedef const nsID& KeyType;
typedef const nsID* KeyTypePointer;
explicit nsIDHashKey(const nsID* aInID) : mID(*aInID) {}
nsIDHashKey(nsIDHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mID(std::move(aOther.mID)) {}
~nsIDHashKey() = default;
KeyType GetKey() const { return mID; }
bool KeyEquals(KeyTypePointer aKey) const { return aKey->Equals(mID); }
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
// Hash the nsID object's raw bytes.
return mozilla::HashBytes(aKey, sizeof(KeyType));
}
enum { ALLOW_MEMMOVE = true };
private:
nsID mID;
};
/**
* hashkey wrapper using nsID* KeyType
*
* @see nsTHashtable::EntryType for specification
*/
class nsIDPointerHashKey : public PLDHashEntryHdr {
public:
typedef const nsID* KeyType;
typedef const nsID* KeyTypePointer;
explicit nsIDPointerHashKey(const nsID* aInID) : mID(aInID) {}
nsIDPointerHashKey(nsIDPointerHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mID(aOther.mID) {}
~nsIDPointerHashKey() = default;
KeyType GetKey() const { return mID; }
bool KeyEquals(KeyTypePointer aKey) const { return aKey->Equals(*mID); }
static KeyTypePointer KeyToPointer(KeyType aKey) { return aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
// Hash the nsID object's raw bytes.
return mozilla::HashBytes(aKey, sizeof(*aKey));
}
enum { ALLOW_MEMMOVE = true };
private:
const nsID* mID;
};
/**
* hashkey wrapper for "dependent" const char*; this class does not "own"
* its string pointer.
*
* This class must only be used if the strings have a lifetime longer than
* the hashtable they occupy. This normally occurs only for static
* strings or strings that have been arena-allocated.
*
* @see nsTHashtable::EntryType for specification
*/
class nsDepCharHashKey : public PLDHashEntryHdr {
public:
typedef const char* KeyType;
typedef const char* KeyTypePointer;
explicit nsDepCharHashKey(const char* aKey) : mKey(aKey) {}
nsDepCharHashKey(nsDepCharHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mKey(std::move(aOther.mKey)) {}
~nsDepCharHashKey() = default;
const char* GetKey() const { return mKey; }
bool KeyEquals(const char* aKey) const { return !strcmp(mKey, aKey); }
static const char* KeyToPointer(const char* aKey) { return aKey; }
static PLDHashNumber HashKey(const char* aKey) {
return mozilla::HashString(aKey);
}
enum { ALLOW_MEMMOVE = true };
private:
const char* mKey;
};
/**
* hashkey wrapper for const char*; at construction, this class duplicates
* a string pointed to by the pointer so that it doesn't matter whether or not
* the string lives longer than the hash table.
*/
class nsCharPtrHashKey : public PLDHashEntryHdr {
public:
typedef const char* KeyType;
typedef const char* KeyTypePointer;
explicit nsCharPtrHashKey(const char* aKey) : mKey(strdup(aKey)) {}
nsCharPtrHashKey(const nsCharPtrHashKey&) = delete;
nsCharPtrHashKey(nsCharPtrHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mKey(aOther.mKey) {
aOther.mKey = nullptr;
}
~nsCharPtrHashKey() {
if (mKey) {
free(const_cast<char*>(mKey));
}
}
const char* GetKey() const { return mKey; }
bool KeyEquals(KeyTypePointer aKey) const { return !strcmp(mKey, aKey); }
static KeyTypePointer KeyToPointer(KeyType aKey) { return aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return mozilla::HashString(aKey);
}
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(mKey);
}
enum { ALLOW_MEMMOVE = true };
private:
const char* mKey;
};
/**
* hashkey wrapper for const char16_t*; at construction, this class duplicates
* a string pointed to by the pointer so that it doesn't matter whether or not
* the string lives longer than the hash table.
*/
class nsUnicharPtrHashKey : public PLDHashEntryHdr {
public:
typedef const char16_t* KeyType;
typedef const char16_t* KeyTypePointer;
explicit nsUnicharPtrHashKey(const char16_t* aKey) : mKey(NS_xstrdup(aKey)) {}
nsUnicharPtrHashKey(const nsUnicharPtrHashKey& aToCopy) = delete;
nsUnicharPtrHashKey(nsUnicharPtrHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mKey(aOther.mKey) {
aOther.mKey = nullptr;
}
~nsUnicharPtrHashKey() {
if (mKey) {
free(const_cast<char16_t*>(mKey));
}
}
const char16_t* GetKey() const { return mKey; }
bool KeyEquals(KeyTypePointer aKey) const { return !NS_strcmp(mKey, aKey); }
static KeyTypePointer KeyToPointer(KeyType aKey) { return aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return mozilla::HashString(aKey);
}
size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const {
return aMallocSizeOf(mKey);
}
enum { ALLOW_MEMMOVE = true };
private:
const char16_t* mKey;
};
namespace mozilla {
template <typename T>
PLDHashNumber Hash(const T& aValue) {
return aValue.Hash();
}
} // namespace mozilla
/**
* Hashtable key class to use with objects for which Hash() and operator==()
* are defined.
*/
template <typename T>
class nsGenericHashKey : public PLDHashEntryHdr {
public:
typedef const T& KeyType;
typedef const T* KeyTypePointer;
explicit nsGenericHashKey(KeyTypePointer aKey) : mKey(*aKey) {}
nsGenericHashKey(const nsGenericHashKey&) = delete;
nsGenericHashKey(nsGenericHashKey&& aOther)
: PLDHashEntryHdr(std::move(aOther)), mKey(std::move(aOther.mKey)) {}
KeyType GetKey() const { return mKey; }
bool KeyEquals(KeyTypePointer aKey) const { return *aKey == mKey; }
static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
static PLDHashNumber HashKey(KeyTypePointer aKey) {
return ::mozilla::Hash(*aKey);
}
enum { ALLOW_MEMMOVE = true };
private:
T mKey;
};
#endif // nsTHashKeys_h__