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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /xpcom/glue/nsHashKeys.h
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
downloaduxp-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz
Add m-esr52 at 52.6.0
Diffstat (limited to 'xpcom/glue/nsHashKeys.h')
-rw-r--r--xpcom/glue/nsHashKeys.h660
1 files changed, 660 insertions, 0 deletions
diff --git a/xpcom/glue/nsHashKeys.h b/xpcom/glue/nsHashKeys.h
new file mode 100644
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+++ b/xpcom/glue/nsHashKeys.h
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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsTHashKeys_h__
+#define nsTHashKeys_h__
+
+#include "nsID.h"
+#include "nsISupports.h"
+#include "nsIHashable.h"
+#include "nsAutoPtr.h"
+#include "nsCOMPtr.h"
+#include "PLDHashTable.h"
+#include <new>
+
+#include "nsStringGlue.h"
+#include "nsCRTGlue.h"
+#include "nsUnicharUtils.h"
+#include "nsPointerHashKeys.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "mozilla/HashFunctions.h"
+#include "mozilla/Move.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
+ * nsPtrHashKey
+ * nsClearingPtrHashKey
+ * nsVoidPtrHashKey
+ * nsClearingVoidPtrHashKey
+ * nsISupportsHashKey
+ * nsIDHashKey
+ * nsDepCharHashKey
+ * nsCharPtrHashKey
+ * nsUnicharPtrHashKey
+ * nsHashableHashKey
+ * 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& aToCopy) : mStr(aToCopy.mStr) {}
+ ~nsStringHashKey() {}
+
+ 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:
+ const nsString mStr;
+};
+
+#ifdef MOZILLA_INTERNAL_API
+
+/**
+ * hashkey wrapper using nsAString KeyType
+ *
+ * This is internal-API only because nsCaseInsensitiveStringComparator is
+ * internal-only.
+ *
+ * @see nsTHashtable::EntryType for specification
+ */
+class nsStringCaseInsensitiveHashKey : public PLDHashEntryHdr
+{
+public:
+ typedef const nsAString& KeyType;
+ typedef const nsAString* KeyTypePointer;
+
+ explicit nsStringCaseInsensitiveHashKey(KeyTypePointer aStr)
+ : mStr(*aStr)
+ {
+ // take it easy just deal HashKey
+ }
+ nsStringCaseInsensitiveHashKey(const nsStringCaseInsensitiveHashKey& aToCopy)
+ : mStr(aToCopy.mStr)
+ {
+ }
+ ~nsStringCaseInsensitiveHashKey() {}
+
+ KeyType GetKey() const { return mStr; }
+ bool KeyEquals(const KeyTypePointer aKey) const
+ {
+ return mStr.Equals(*aKey, nsCaseInsensitiveStringComparator());
+ }
+
+ static KeyTypePointer KeyToPointer(KeyType aKey) { return &aKey; }
+ static PLDHashNumber HashKey(const KeyTypePointer aKey)
+ {
+ nsAutoString 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 nsString mStr;
+};
+
+#endif
+
+/**
+ * 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(const nsCStringHashKey& aToCopy) : mStr(aToCopy.mStr) {}
+ ~nsCStringHashKey() {}
+
+ 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 uint32_t KeyType
+ *
+ * @see nsTHashtable::EntryType for specification
+ */
+class nsUint32HashKey : public PLDHashEntryHdr
+{
+public:
+ typedef const uint32_t& KeyType;
+ typedef const uint32_t* KeyTypePointer;
+
+ explicit nsUint32HashKey(KeyTypePointer aKey) : mValue(*aKey) {}
+ nsUint32HashKey(const nsUint32HashKey& aToCopy) : mValue(aToCopy.mValue) {}
+ ~nsUint32HashKey() {}
+
+ 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 *aKey; }
+ enum { ALLOW_MEMMOVE = true };
+
+private:
+ const uint32_t mValue;
+};
+
+/**
+ * hashkey wrapper using uint64_t KeyType
+ *
+ * @see nsTHashtable::EntryType for specification
+ */
+class nsUint64HashKey : public PLDHashEntryHdr
+{
+public:
+ typedef const uint64_t& KeyType;
+ typedef const uint64_t* KeyTypePointer;
+
+ explicit nsUint64HashKey(KeyTypePointer aKey) : mValue(*aKey) {}
+ nsUint64HashKey(const nsUint64HashKey& aToCopy) : mValue(aToCopy.mValue) {}
+ ~nsUint64HashKey() {}
+
+ 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 PLDHashNumber(*aKey);
+ }
+ enum { ALLOW_MEMMOVE = true };
+
+private:
+ const uint64_t mValue;
+};
+
+/**
+ * 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(const nsFloatHashKey& aToCopy) : mValue(aToCopy.mValue) {}
+ ~nsFloatHashKey() {}
+
+ 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 nsISupports* KeyType
+ *
+ * @see nsTHashtable::EntryType for specification
+ */
+class nsISupportsHashKey : public PLDHashEntryHdr
+{
+public:
+ typedef nsISupports* KeyType;
+ typedef const nsISupports* KeyTypePointer;
+
+ explicit nsISupportsHashKey(const nsISupports* aKey)
+ : mSupports(const_cast<nsISupports*>(aKey))
+ {
+ }
+ nsISupportsHashKey(const nsISupportsHashKey& aToCopy)
+ : mSupports(aToCopy.mSupports)
+ {
+ }
+ ~nsISupportsHashKey() {}
+
+ 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 NS_PTR_TO_UINT32(aKey) >> 2;
+ }
+ 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:
+ typedef T* KeyType;
+ typedef const T* KeyTypePointer;
+
+ explicit nsRefPtrHashKey(const T* aKey) : mKey(const_cast<T*>(aKey)) {}
+ nsRefPtrHashKey(const nsRefPtrHashKey& aToCopy) : mKey(aToCopy.mKey) {}
+ ~nsRefPtrHashKey() {}
+
+ 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 NS_PTR_TO_UINT32(aKey) >> 2;
+ }
+ 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 T* KeyType that sets key to nullptr upon
+ * destruction. Relevant only in cases where a memory pointer-scanner
+ * like valgrind might get confused about stale references.
+ *
+ * @see nsTHashtable::EntryType for specification
+ */
+
+template<class T>
+class nsClearingPtrHashKey : public nsPtrHashKey<T>
+{
+public:
+ explicit nsClearingPtrHashKey(const T* aKey) : nsPtrHashKey<T>(aKey) {}
+ nsClearingPtrHashKey(const nsClearingPtrHashKey<T>& aToCopy)
+ : nsPtrHashKey<T>(aToCopy)
+ {
+ }
+ ~nsClearingPtrHashKey() { nsPtrHashKey<T>::mKey = nullptr; }
+};
+
+typedef nsClearingPtrHashKey<const void> nsClearingVoidPtrHashKey;
+
+/**
+ * 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() {}
+
+ 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 NS_PTR_TO_UINT32(*aKey) >> 2;
+ }
+ 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(const nsIDHashKey& aToCopy) : mID(aToCopy.mID) {}
+ ~nsIDHashKey() {}
+
+ 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:
+ 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(const nsDepCharHashKey& aToCopy) : mKey(aToCopy.mKey) {}
+ ~nsDepCharHashKey() {}
+
+ 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& aToCopy)
+ : mKey(strdup(aToCopy.mKey))
+ {
+ }
+
+ nsCharPtrHashKey(nsCharPtrHashKey&& 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_strdup(aKey)) {}
+ nsUnicharPtrHashKey(const nsUnicharPtrHashKey& aToCopy)
+ : mKey(NS_strdup(aToCopy.mKey))
+ {
+ }
+
+ nsUnicharPtrHashKey(nsUnicharPtrHashKey&& aOther)
+ : mKey(aOther.mKey)
+ {
+ aOther.mKey = nullptr;
+ }
+
+ ~nsUnicharPtrHashKey()
+ {
+ if (mKey) {
+ NS_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;
+};
+
+/**
+ * Hashtable key class to use with objects that support nsIHashable
+ */
+class nsHashableHashKey : public PLDHashEntryHdr
+{
+public:
+ typedef nsIHashable* KeyType;
+ typedef const nsIHashable* KeyTypePointer;
+
+ explicit nsHashableHashKey(const nsIHashable* aKey)
+ : mKey(const_cast<nsIHashable*>(aKey))
+ {
+ }
+ nsHashableHashKey(const nsHashableHashKey& aToCopy) : mKey(aToCopy.mKey) {}
+ ~nsHashableHashKey() {}
+
+ nsIHashable* GetKey() const { return mKey; }
+
+ bool KeyEquals(const nsIHashable* aKey) const
+ {
+ bool eq;
+ if (NS_SUCCEEDED(mKey->Equals(const_cast<nsIHashable*>(aKey), &eq))) {
+ return eq;
+ }
+ return false;
+ }
+
+ static const nsIHashable* KeyToPointer(nsIHashable* aKey) { return aKey; }
+ static PLDHashNumber HashKey(const nsIHashable* aKey)
+ {
+ uint32_t code = 8888; // magic number if GetHashCode fails :-(
+#ifdef DEBUG
+ nsresult rv =
+#endif
+ const_cast<nsIHashable*>(aKey)->GetHashCode(&code);
+ NS_ASSERTION(NS_SUCCEEDED(rv), "GetHashCode should not throw!");
+ return code;
+ }
+
+ enum { ALLOW_MEMMOVE = true };
+
+private:
+ nsCOMPtr<nsIHashable> 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<T>& aOther) : mKey(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__