/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- * vim: set ts=8 sts=4 et sw=4 tw=99: * 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/. */ /* * JS allocation policies. * * The allocators here are for system memory with lifetimes which are not * managed by the GC. See the comment at the top of vm/MallocProvider.h. */ #ifndef jsalloc_h #define jsalloc_h #include "js/TypeDecls.h" #include "js/Utility.h" extern JS_PUBLIC_API(void) JS_ReportOutOfMemory(JSContext* cx); namespace js { enum class AllocFunction { Malloc, Calloc, Realloc }; struct ContextFriendFields; /* Policy for using system memory functions and doing no error reporting. */ class SystemAllocPolicy { public: template <typename T> T* maybe_pod_malloc(size_t numElems) { return js_pod_malloc<T>(numElems); } template <typename T> T* maybe_pod_calloc(size_t numElems) { return js_pod_calloc<T>(numElems); } template <typename T> T* maybe_pod_realloc(T* p, size_t oldSize, size_t newSize) { return js_pod_realloc<T>(p, oldSize, newSize); } template <typename T> T* pod_malloc(size_t numElems) { return maybe_pod_malloc<T>(numElems); } template <typename T> T* pod_calloc(size_t numElems) { return maybe_pod_calloc<T>(numElems); } template <typename T> T* pod_realloc(T* p, size_t oldSize, size_t newSize) { return maybe_pod_realloc<T>(p, oldSize, newSize); } void free_(void* p) { js_free(p); } void reportAllocOverflow() const {} bool checkSimulatedOOM() const { return !js::oom::ShouldFailWithOOM(); } }; class ExclusiveContext; JS_FRIEND_API(void) ReportOutOfMemory(ExclusiveContext* cxArg); /* * Allocation policy that calls the system memory functions and reports errors * to the context. Since the JSContext given on construction is stored for * the lifetime of the container, this policy may only be used for containers * whose lifetime is a shorter than the given JSContext. * * FIXME bug 647103 - rewrite this in terms of temporary allocation functions, * not the system ones. */ class TempAllocPolicy { ContextFriendFields* const cx_; /* * Non-inline helper to call JSRuntime::onOutOfMemory with minimal * code bloat. */ JS_FRIEND_API(void*) onOutOfMemory(AllocFunction allocFunc, size_t nbytes, void* reallocPtr = nullptr); template <typename T> T* onOutOfMemoryTyped(AllocFunction allocFunc, size_t numElems, void* reallocPtr = nullptr) { size_t bytes; if (MOZ_UNLIKELY(!CalculateAllocSize<T>(numElems, &bytes))) return nullptr; return static_cast<T*>(onOutOfMemory(allocFunc, bytes, reallocPtr)); } public: MOZ_IMPLICIT TempAllocPolicy(JSContext* cx) : cx_((ContextFriendFields*) cx) {} // :( MOZ_IMPLICIT TempAllocPolicy(ContextFriendFields* cx) : cx_(cx) {} template <typename T> T* maybe_pod_malloc(size_t numElems) { return js_pod_malloc<T>(numElems); } template <typename T> T* maybe_pod_calloc(size_t numElems) { return js_pod_calloc<T>(numElems); } template <typename T> T* maybe_pod_realloc(T* prior, size_t oldSize, size_t newSize) { return js_pod_realloc<T>(prior, oldSize, newSize); } template <typename T> T* pod_malloc(size_t numElems) { T* p = maybe_pod_malloc<T>(numElems); if (MOZ_UNLIKELY(!p)) p = onOutOfMemoryTyped<T>(AllocFunction::Malloc, numElems); return p; } template <typename T> T* pod_calloc(size_t numElems) { T* p = maybe_pod_calloc<T>(numElems); if (MOZ_UNLIKELY(!p)) p = onOutOfMemoryTyped<T>(AllocFunction::Calloc, numElems); return p; } template <typename T> T* pod_realloc(T* prior, size_t oldSize, size_t newSize) { T* p2 = maybe_pod_realloc<T>(prior, oldSize, newSize); if (MOZ_UNLIKELY(!p2)) p2 = onOutOfMemoryTyped<T>(AllocFunction::Realloc, newSize, prior); return p2; } void free_(void* p) { js_free(p); } JS_FRIEND_API(void) reportAllocOverflow() const; bool checkSimulatedOOM() const { if (js::oom::ShouldFailWithOOM()) { js::ReportOutOfMemory(reinterpret_cast<ExclusiveContext*>(cx_)); return false; } return true; } }; } /* namespace js */ #endif /* jsalloc_h */