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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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/. */
/* Low-level memory-allocation functions. */
#ifndef js_MemoryFunctions_h
#define js_MemoryFunctions_h
#include "mozilla/Assertions.h" // MOZ_ASSERT
#include <stddef.h> // size_t
#include "jstypes.h" // JS_PUBLIC_API
struct JS_PUBLIC_API JSContext;
class JS_PUBLIC_API JSFreeOp;
class JS_PUBLIC_API JSObject;
struct JS_PUBLIC_API JSRuntime;
extern JS_PUBLIC_API void* JS_malloc(JSContext* cx, size_t nbytes);
extern JS_PUBLIC_API void* JS_realloc(JSContext* cx, void* p, size_t oldBytes,
size_t newBytes);
/**
* A wrapper for |js_free(p)| that may delay |js_free(p)| invocation as a
* performance optimization. |cx| may be nullptr.
*/
extern JS_PUBLIC_API void JS_free(JSContext* cx, void* p);
/**
* Same as above, but for buffers that will be used with the BYOB
* (Bring Your Own Buffer) JSString creation functions, such as
* JS_NewLatin1String and JS_NewUCString
*/
extern JS_PUBLIC_API void* JS_string_malloc(JSContext* cx, size_t nbytes);
extern JS_PUBLIC_API void* JS_string_realloc(JSContext* cx, void* p,
size_t oldBytes, size_t newBytes);
extern JS_PUBLIC_API void JS_string_free(JSContext* cx, void* p);
/**
* A wrapper for |js_free(p)| that may delay |js_free(p)| invocation as a
* performance optimization as specified by the given JSFreeOp instance.
*/
extern JS_PUBLIC_API void JS_freeop(JSFreeOp* fop, void* p);
namespace JS {
/**
* The different possible memory uses to pass to Add/RemoveAssociatedMemory.
*/
#define JS_FOR_EACH_PUBLIC_MEMORY_USE(_) \
_(XPCWrappedNative) \
_(DOMBinding) \
_(CTypeFFIType) \
_(CTypeFFITypeElements) \
_(CTypeFunctionInfo) \
_(CTypeFieldInfo) \
_(CDataBufferPtr) \
_(CDataBuffer) \
_(CClosureInfo) \
_(CTypesInt64) \
_(Embedding1) \
_(Embedding2) \
_(Embedding3) \
_(Embedding4) \
_(Embedding5)
enum class MemoryUse : uint8_t {
#define DEFINE_MEMORY_USE(Name) Name,
JS_FOR_EACH_PUBLIC_MEMORY_USE(DEFINE_MEMORY_USE)
#undef DEFINE_MEMORY_USE
};
/**
* Advise the GC of external memory owned by a JSObject. This is used to
* determine when to collect zones. Calls must be matched by calls to
* RemoveAssociatedMemory() when the memory is deallocated or no longer owned by
* the object.
*/
extern JS_PUBLIC_API void AddAssociatedMemory(JSObject* obj, size_t nbytes,
MemoryUse use);
/**
* Advise the GC that external memory reported by JS::AddAssociatedMemory() is
* no longer owned by a JSObject. Calls must match those to
* AddAssociatedMemory().
*/
extern JS_PUBLIC_API void RemoveAssociatedMemory(JSObject* obj, size_t nbytes,
MemoryUse use);
} // namespace JS
#endif /* js_MemoryFunctions_h */