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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/. */
+
+/* SpiderMonkey initialization and shutdown APIs. */
+
+#ifndef js_Initialization_h
+#define js_Initialization_h
+
+#include "jstypes.h"
+
+namespace JS {
+namespace detail {
+
+enum class InitState { Uninitialized = 0, Initializing, Running, ShutDown };
+
+/**
+ * SpiderMonkey's initialization status is tracked here, and it controls things
+ * that should happen only once across all runtimes. It's an API requirement
+ * that JS_Init (and JS_ShutDown, if called) be called in a thread-aware
+ * manner, so this (internal -- embedders, don't use!) variable doesn't need to
+ * be atomic.
+ */
+extern JS_PUBLIC_DATA InitState libraryInitState;
+
+extern JS_PUBLIC_API const char* InitWithFailureDiagnostic(bool isDebugBuild);
+
+} // namespace detail
+} // namespace JS
+
+// These are equivalent to ICU's |UMemAllocFn|, |UMemReallocFn|, and
+// |UMemFreeFn| types. The first argument (called |context| in the ICU docs)
+// will always be nullptr and should be ignored.
+typedef void* (*JS_ICUAllocFn)(const void*, size_t size);
+typedef void* (*JS_ICUReallocFn)(const void*, void* p, size_t size);
+typedef void (*JS_ICUFreeFn)(const void*, void* p);
+
+/**
+ * This function can be used to track memory used by ICU. If it is called, it
+ * *must* be called before JS_Init. Don't use it unless you know what you're
+ * doing!
+ */
+extern JS_PUBLIC_API bool JS_SetICUMemoryFunctions(JS_ICUAllocFn allocFn,
+ JS_ICUReallocFn reallocFn,
+ JS_ICUFreeFn freeFn);
+
+/**
+ * Initialize SpiderMonkey, returning true only if initialization succeeded.
+ * Once this method has succeeded, it is safe to call JS_NewContext and other
+ * JSAPI methods.
+ *
+ * This method must be called before any other JSAPI method is used on any
+ * thread. Once it has been used, it is safe to call any JSAPI method, and it
+ * remains safe to do so until JS_ShutDown is correctly called.
+ *
+ * It is currently not possible to initialize SpiderMonkey multiple times (that
+ * is, calling JS_Init/JSAPI methods/JS_ShutDown in that order, then doing so
+ * again). This restriction may eventually be lifted.
+ */
+inline bool JS_Init(void) {
+#ifdef DEBUG
+ return !JS::detail::InitWithFailureDiagnostic(true);
+#else
+ return !JS::detail::InitWithFailureDiagnostic(false);
+#endif
+}
+
+/**
+ * A variant of JS_Init. On success it returns nullptr. On failure it returns a
+ * pointer to a string literal that describes how initialization failed, which
+ * can be useful for debugging purposes.
+ */
+inline const char* JS_InitWithFailureDiagnostic(void) {
+#ifdef DEBUG
+ return JS::detail::InitWithFailureDiagnostic(true);
+#else
+ return JS::detail::InitWithFailureDiagnostic(false);
+#endif
+}
+
+/*
+ * Returns true if SpiderMonkey has been initialized successfully, even if it
+ * has possibly been shut down.
+ *
+ * Note that it is the responsibility of the embedder to call JS_Init() and
+ * JS_ShutDown() at the correct times, and therefore this API should ideally not
+ * be necessary to use. This is only intended to be used in cases where the
+ * embedder isn't in full control of deciding whether to initialize SpiderMonkey
+ * or hand off the task to another consumer.
+ */
+inline bool JS_IsInitialized(void) {
+ return JS::detail::libraryInitState >= JS::detail::InitState::Running;
+}
+
+/**
+ * Destroy free-standing resources allocated by SpiderMonkey, not associated
+ * with any runtime, context, or other structure.
+ *
+ * This method should be called after all other JSAPI data has been properly
+ * cleaned up: every new runtime must have been destroyed, every new context
+ * must have been destroyed, and so on. Calling this method before all other
+ * resources have been destroyed has undefined behavior.
+ *
+ * Failure to call this method, at present, has no adverse effects other than
+ * leaking memory. This may not always be the case; it's recommended that all
+ * embedders call this method when all other JSAPI operations have completed.
+ *
+ * It is currently not possible to initialize SpiderMonkey multiple times (that
+ * is, calling JS_Init/JSAPI methods/JS_ShutDown in that order, then doing so
+ * again). This restriction may eventually be lifted.
+ */
+extern JS_PUBLIC_API void JS_ShutDown(void);
+
+#endif /* js_Initialization_h */