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+/*
+ * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB. If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef WTF_FastMalloc_h
+#define WTF_FastMalloc_h
+
+#include "Platform.h"
+#include "PossiblyNull.h"
+#include <stdlib.h>
+#include <new>
+
+namespace WTF {
+
+ // These functions call CRASH() if an allocation fails.
+ void* fastMalloc(size_t);
+ void* fastZeroedMalloc(size_t);
+ void* fastCalloc(size_t numElements, size_t elementSize);
+ void* fastRealloc(void*, size_t);
+ char* fastStrDup(const char*);
+ size_t fastMallocSize(const void*);
+
+ struct TryMallocReturnValue {
+ TryMallocReturnValue(void* data)
+ : m_data(data)
+ {
+ }
+ TryMallocReturnValue(const TryMallocReturnValue& source)
+ : m_data(source.m_data)
+ {
+ source.m_data = 0;
+ }
+ ~TryMallocReturnValue() { ASSERT(!m_data); }
+ template <typename T> bool getValue(T& data) WARN_UNUSED_RETURN;
+ template <typename T> operator PossiblyNull<T>()
+ {
+ T value;
+ getValue(value);
+ return PossiblyNull<T>(value);
+ }
+ private:
+ mutable void* m_data;
+ };
+
+ template <typename T> bool TryMallocReturnValue::getValue(T& data)
+ {
+ union u { void* data; T target; } res;
+ res.data = m_data;
+ data = res.target;
+ bool returnValue = !!m_data;
+ m_data = 0;
+ return returnValue;
+ }
+
+ TryMallocReturnValue tryFastMalloc(size_t n);
+ TryMallocReturnValue tryFastZeroedMalloc(size_t n);
+ TryMallocReturnValue tryFastCalloc(size_t n_elements, size_t element_size);
+ TryMallocReturnValue tryFastRealloc(void* p, size_t n);
+
+ void fastFree(void*);
+
+#ifndef NDEBUG
+ void fastMallocForbid();
+ void fastMallocAllow();
+#endif
+
+ void releaseFastMallocFreeMemory();
+
+ struct FastMallocStatistics {
+ size_t reservedVMBytes;
+ size_t committedVMBytes;
+ size_t freeListBytes;
+ };
+ FastMallocStatistics fastMallocStatistics();
+
+ // This defines a type which holds an unsigned integer and is the same
+ // size as the minimally aligned memory allocation.
+ typedef unsigned long long AllocAlignmentInteger;
+
+ namespace Internal {
+ enum AllocType { // Start with an unusual number instead of zero, because zero is common.
+ AllocTypeMalloc = 0x375d6750, // Encompasses fastMalloc, fastZeroedMalloc, fastCalloc, fastRealloc.
+ AllocTypeClassNew, // Encompasses class operator new from FastAllocBase.
+ AllocTypeClassNewArray, // Encompasses class operator new[] from FastAllocBase.
+ AllocTypeFastNew, // Encompasses fastNew.
+ AllocTypeFastNewArray, // Encompasses fastNewArray.
+ AllocTypeNew, // Encompasses global operator new.
+ AllocTypeNewArray // Encompasses global operator new[].
+ };
+ }
+
+#if ENABLE(FAST_MALLOC_MATCH_VALIDATION)
+
+ // Malloc validation is a scheme whereby a tag is attached to an
+ // allocation which identifies how it was originally allocated.
+ // This allows us to verify that the freeing operation matches the
+ // allocation operation. If memory is allocated with operator new[]
+ // but freed with free or delete, this system would detect that.
+ // In the implementation here, the tag is an integer prepended to
+ // the allocation memory which is assigned one of the AllocType
+ // enumeration values. An alternative implementation of this
+ // scheme could store the tag somewhere else or ignore it.
+ // Users of FastMalloc don't need to know or care how this tagging
+ // is implemented.
+
+ namespace Internal {
+
+ // Return the AllocType tag associated with the allocated block p.
+ inline AllocType fastMallocMatchValidationType(const void* p)
+ {
+ const AllocAlignmentInteger* type = static_cast<const AllocAlignmentInteger*>(p) - 1;
+ return static_cast<AllocType>(*type);
+ }
+
+ // Return the address of the AllocType tag associated with the allocated block p.
+ inline AllocAlignmentInteger* fastMallocMatchValidationValue(void* p)
+ {
+ return reinterpret_cast<AllocAlignmentInteger*>(static_cast<char*>(p) - sizeof(AllocAlignmentInteger));
+ }
+
+ // Set the AllocType tag to be associaged with the allocated block p.
+ inline void setFastMallocMatchValidationType(void* p, AllocType allocType)
+ {
+ AllocAlignmentInteger* type = static_cast<AllocAlignmentInteger*>(p) - 1;
+ *type = static_cast<AllocAlignmentInteger>(allocType);
+ }
+
+ // Handle a detected alloc/free mismatch. By default this calls CRASH().
+ void fastMallocMatchFailed(void* p);
+
+ } // namespace Internal
+
+ // This is a higher level function which is used by FastMalloc-using code.
+ inline void fastMallocMatchValidateMalloc(void* p, Internal::AllocType allocType)
+ {
+ if (!p)
+ return;
+
+ Internal::setFastMallocMatchValidationType(p, allocType);
+ }
+
+ // This is a higher level function which is used by FastMalloc-using code.
+ inline void fastMallocMatchValidateFree(void* p, Internal::AllocType allocType)
+ {
+ if (!p)
+ return;
+
+ if (Internal::fastMallocMatchValidationType(p) != allocType)
+ Internal::fastMallocMatchFailed(p);
+ Internal::setFastMallocMatchValidationType(p, Internal::AllocTypeMalloc); // Set it to this so that fastFree thinks it's OK.
+ }
+
+#else
+
+ inline void fastMallocMatchValidateMalloc(void*, Internal::AllocType)
+ {
+ }
+
+ inline void fastMallocMatchValidateFree(void*, Internal::AllocType)
+ {
+ }
+
+#endif
+
+} // namespace WTF
+
+using WTF::fastCalloc;
+using WTF::fastFree;
+using WTF::fastMalloc;
+using WTF::fastMallocSize;
+using WTF::fastRealloc;
+using WTF::fastStrDup;
+using WTF::fastZeroedMalloc;
+using WTF::tryFastCalloc;
+using WTF::tryFastMalloc;
+using WTF::tryFastRealloc;
+using WTF::tryFastZeroedMalloc;
+
+#ifndef NDEBUG
+using WTF::fastMallocForbid;
+using WTF::fastMallocAllow;
+#endif
+
+#if COMPILER(GCC) && OS(DARWIN)
+#define WTF_PRIVATE_INLINE __private_extern__ inline __attribute__((always_inline))
+#elif COMPILER(GCC)
+#define WTF_PRIVATE_INLINE inline __attribute__((always_inline))
+#elif COMPILER(MSVC) || COMPILER(RVCT)
+#define WTF_PRIVATE_INLINE __forceinline
+#else
+#define WTF_PRIVATE_INLINE inline
+#endif
+
+#if !defined(_CRTDBG_MAP_ALLOC) && !(defined(USE_SYSTEM_MALLOC) && USE_SYSTEM_MALLOC && !PLATFORM(BREWMP))
+
+// The nothrow functions here are actually not all that helpful, because fastMalloc will
+// call CRASH() rather than returning 0, and returning 0 is what nothrow is all about.
+// But since WebKit code never uses exceptions or nothrow at all, this is probably OK.
+// Long term we will adopt FastAllocBase.h everywhere, and and replace this with
+// debug-only code to make sure we don't use the system malloc via the default operator
+// new by accident.
+
+#if ENABLE(GLOBAL_FASTMALLOC_NEW)
+
+#if COMPILER(MSVC)
+#pragma warning(push)
+#pragma warning(disable: 4290) // Disable the C++ exception specification ignored warning.
+#endif
+WTF_PRIVATE_INLINE void* operator new(size_t size) throw (std::bad_alloc) { return fastMalloc(size); }
+WTF_PRIVATE_INLINE void* operator new(size_t size, const std::nothrow_t&) throw() { return fastMalloc(size); }
+WTF_PRIVATE_INLINE void operator delete(void* p) throw() { fastFree(p); }
+WTF_PRIVATE_INLINE void operator delete(void* p, const std::nothrow_t&) throw() { fastFree(p); }
+WTF_PRIVATE_INLINE void* operator new[](size_t size) throw (std::bad_alloc) { return fastMalloc(size); }
+WTF_PRIVATE_INLINE void* operator new[](size_t size, const std::nothrow_t&) throw() { return fastMalloc(size); }
+WTF_PRIVATE_INLINE void operator delete[](void* p) throw() { fastFree(p); }
+WTF_PRIVATE_INLINE void operator delete[](void* p, const std::nothrow_t&) throw() { fastFree(p); }
+#if COMPILER(MSVC)
+#pragma warning(pop)
+#endif
+
+#endif
+
+#endif
+
+#endif /* WTF_FastMalloc_h */