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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 https://mozilla.org/MPL/2.0/. */
+
+/**
+ * Structures and methods with information about XPCOM interfaces for use by
+ * XPConnect. The static backing data structures used by this file are generated
+ * from xpidl interfaces by the jsonxpt.py and xptcodegen.py scripts.
+ */
+
+#ifndef xptinfo_h
+#define xptinfo_h
+
+#include <stdint.h>
+#include "nsID.h"
+#include "mozilla/Assertions.h"
+#include "jsapi.h"
+#include "js/Symbol.h"
+#include "js/Value.h"
+#include "nsString.h"
+#include "nsTArray.h"
+
+// Forward Declarations
+namespace mozilla {
+namespace dom {
+struct NativePropertyHooks;
+} // namespace dom
+} // namespace mozilla
+
+struct nsXPTInterfaceInfo;
+struct nsXPTType;
+struct nsXPTParamInfo;
+struct nsXPTMethodInfo;
+struct nsXPTConstantInfo;
+struct nsXPTDOMObjectInfo;
+
+enum class nsXPTInterface : uint16_t;
+
+// Internal helper methods.
+namespace xpt {
+namespace detail {
+
+inline const nsXPTInterfaceInfo* GetInterface(uint16_t aIndex);
+inline const nsXPTType& GetType(uint16_t aIndex);
+inline const nsXPTParamInfo& GetParam(uint16_t aIndex);
+inline const nsXPTMethodInfo& GetMethod(uint16_t aIndex);
+inline const nsXPTConstantInfo& GetConstant(uint16_t aIndex);
+inline const nsXPTDOMObjectInfo& GetDOMObjectInfo(uint16_t aIndex);
+inline const char* GetString(uint32_t aIndex);
+
+const nsXPTInterfaceInfo* InterfaceByIID(const nsIID& aIID);
+const nsXPTInterfaceInfo* InterfaceByName(const char* aName);
+
+extern const uint16_t sInterfacesSize;
+
+} // namespace detail
+} // namespace xpt
+
+/*
+ * An Interface describes a single XPCOM interface, including all of its
+ * methods. We don't record non-scriptable interfaces.
+ */
+struct nsXPTInterfaceInfo {
+ // High efficiency getters for Interfaces based on perfect hashes.
+ static const nsXPTInterfaceInfo* ByIID(const nsIID& aIID) {
+ return xpt::detail::InterfaceByIID(aIID);
+ }
+ static const nsXPTInterfaceInfo* ByName(const char* aName) {
+ return xpt::detail::InterfaceByName(aName);
+ }
+
+ static const nsXPTInterfaceInfo* Get(nsXPTInterface aID) {
+ return ByIndex(uint16_t(aID));
+ }
+
+ // These are only needed for Components_interfaces's enumerator.
+ static const nsXPTInterfaceInfo* ByIndex(uint16_t aIndex) {
+ // NOTE: We add 1 here, as the internal index 0 is reserved for null.
+ return xpt::detail::GetInterface(aIndex + 1);
+ }
+ static uint16_t InterfaceCount() { return xpt::detail::sInterfacesSize; }
+
+ // Interface flag getters
+ bool IsFunction() const { return mFunction; }
+ bool IsBuiltinClass() const { return mBuiltinClass; }
+ bool IsMainProcessScriptableOnly() const {
+ return mMainProcessScriptableOnly;
+ }
+
+ const char* Name() const { return xpt::detail::GetString(mName); }
+ const nsIID& IID() const { return mIID; }
+
+ // Get the parent interface, or null if this interface doesn't have a parent.
+ const nsXPTInterfaceInfo* GetParent() const {
+ return xpt::detail::GetInterface(mParent);
+ }
+
+ // Do we have an ancestor interface with the given IID?
+ bool HasAncestor(const nsIID& aIID) const;
+
+ // Get methods & constants
+ uint16_t ConstantCount() const { return mNumConsts; }
+ const nsXPTConstantInfo& Constant(uint16_t aIndex) const;
+ uint16_t MethodCount() const { return mNumMethods; }
+ const nsXPTMethodInfo& Method(uint16_t aIndex) const;
+
+ nsresult GetMethodInfo(uint16_t aIndex, const nsXPTMethodInfo** aInfo) const;
+ nsresult GetConstant(uint16_t aIndex, JS::MutableHandle<JS::Value> constant,
+ char** aName) const;
+
+ ////////////////////////////////////////////////////////////////
+ // Ensure these fields are in the same order as xptcodegen.py //
+ ////////////////////////////////////////////////////////////////
+
+ nsID mIID;
+ uint32_t mName; // Index into xpt::detail::sStrings
+
+ uint16_t mParent : 14;
+ uint16_t mBuiltinClass : 1;
+ // XXX(nika): Do we need this if we don't have addons anymore?
+ uint16_t mMainProcessScriptableOnly : 1;
+
+ uint16_t mMethods; // Index into xpt::detail::sMethods
+
+ uint16_t mConsts : 14; // Index into xpt::detail::sConsts
+ uint16_t mFunction : 1;
+ // uint16_t unused : 1;
+
+ uint8_t mNumMethods; // NOTE(24/04/18): largest=nsIDocShell (193)
+ uint8_t mNumConsts; // NOTE(24/04/18): largest=nsIAccessibleRole (175)
+};
+
+// The fields in nsXPTInterfaceInfo were carefully ordered to minimize size.
+static_assert(sizeof(nsXPTInterfaceInfo) == 28, "wrong size?");
+
+/*
+ * The following enum represents contains the different tag types which
+ * can be found in nsXPTTypeInfo::mTag.
+ *
+ * WARNING: mTag is 5 bits wide, supporting at most 32 tags.
+ */
+enum nsXPTTypeTag : uint8_t {
+ // Arithmetic (POD) Types
+ // - Do not require cleanup,
+ // - All bit patterns are valid,
+ // - Outparams may be uninitialized by caller,
+ // - Directly supported in xptcall.
+ //
+ // NOTE: The name 'Arithmetic' comes from Harbison/Steele. Despite being a tad
+ // unclear, it is used frequently in xptcall, so is unlikely to be changed.
+ TD_INT8 = 0,
+ TD_INT16 = 1,
+ TD_INT32 = 2,
+ TD_INT64 = 3,
+ TD_UINT8 = 4,
+ TD_UINT16 = 5,
+ TD_UINT32 = 6,
+ TD_UINT64 = 7,
+ TD_FLOAT = 8,
+ TD_DOUBLE = 9,
+ TD_BOOL = 10,
+ TD_CHAR = 11,
+ TD_WCHAR = 12,
+ _TD_LAST_ARITHMETIC = TD_WCHAR,
+
+ // Pointer Types
+ // - Require cleanup unless NULL,
+ // - All-zeros (NULL) bit pattern is valid,
+ // - Outparams may be uninitialized by caller,
+ // - Supported in xptcall as raw pointer.
+ TD_VOID = 13,
+ TD_NSIDPTR = 14,
+ TD_PSTRING = 15,
+ TD_PWSTRING = 16,
+ TD_INTERFACE_TYPE = 17,
+ TD_INTERFACE_IS_TYPE = 18,
+ TD_LEGACY_ARRAY = 19,
+ TD_PSTRING_SIZE_IS = 20,
+ TD_PWSTRING_SIZE_IS = 21,
+ TD_DOMOBJECT = 22,
+ TD_PROMISE = 23,
+ _TD_LAST_POINTER = TD_PROMISE,
+
+ // Complex Types
+ // - Require cleanup,
+ // - Always passed indirectly,
+ // - Outparams must be initialized by caller,
+ // - Supported in xptcall due to indirection.
+ TD_UTF8STRING = 24,
+ TD_CSTRING = 25,
+ TD_ASTRING = 26,
+ TD_NSID = 27,
+ TD_JSVAL = 28,
+ TD_ARRAY = 29,
+ _TD_LAST_COMPLEX = TD_ARRAY
+};
+
+static_assert(_TD_LAST_COMPLEX < 32, "nsXPTTypeTag must fit in 5 bits");
+
+/*
+ * A nsXPTType is a union used to identify the type of a method argument or
+ * return value. The internal data is stored as an 5-bit tag, and two 8-bit
+ * integers, to keep alignment requirements low.
+ *
+ * nsXPTType contains 3 extra bits, reserved for use by nsXPTParamInfo.
+ */
+struct nsXPTType {
+ nsXPTTypeTag Tag() const { return static_cast<nsXPTTypeTag>(mTag); }
+
+ // The index in the function argument list which should be used when
+ // determining the iid_is or size_is properties of this dependent type.
+ uint8_t ArgNum() const {
+ MOZ_ASSERT(Tag() == TD_INTERFACE_IS_TYPE || Tag() == TD_PSTRING_SIZE_IS ||
+ Tag() == TD_PWSTRING_SIZE_IS || Tag() == TD_LEGACY_ARRAY);
+ return mData1;
+ }
+
+ private:
+ // Helper for reading 16-bit data values split between mData1 and mData2.
+ uint16_t Data16() const {
+ return static_cast<uint16_t>(mData1 << 8) | mData2;
+ }
+
+ public:
+ // Get the type of the element in the current array or sequence. Arrays only
+ // fit 8 bits of type data, while sequences support up to 16 bits of type data
+ // due to not needing to store an ArgNum.
+ const nsXPTType& ArrayElementType() const {
+ if (Tag() == TD_LEGACY_ARRAY) {
+ return xpt::detail::GetType(mData2);
+ }
+ MOZ_ASSERT(Tag() == TD_ARRAY);
+ return xpt::detail::GetType(Data16());
+ }
+
+ // We store the 16-bit iface value as two 8-bit values in order to
+ // avoid 16-bit alignment requirements for XPTTypeDescriptor, which
+ // reduces its size and also the size of XPTParamDescriptor.
+ const nsXPTInterfaceInfo* GetInterface() const {
+ MOZ_ASSERT(Tag() == TD_INTERFACE_TYPE);
+ return xpt::detail::GetInterface(Data16());
+ }
+
+ const nsXPTDOMObjectInfo& GetDOMObjectInfo() const {
+ MOZ_ASSERT(Tag() == TD_DOMOBJECT);
+ return xpt::detail::GetDOMObjectInfo(Data16());
+ }
+
+ // See the comments in nsXPTTypeTag for an explanation as to what each of
+ // these categories mean.
+ bool IsArithmetic() const { return Tag() <= _TD_LAST_ARITHMETIC; }
+ bool IsPointer() const {
+ return !IsArithmetic() && Tag() <= _TD_LAST_POINTER;
+ }
+ bool IsComplex() const { return Tag() > _TD_LAST_POINTER; }
+
+ bool IsInterfacePointer() const {
+ return Tag() == TD_INTERFACE_TYPE || Tag() == TD_INTERFACE_IS_TYPE;
+ }
+
+ bool IsDependent() const {
+ return (Tag() == TD_ARRAY && InnermostType().IsDependent()) ||
+ Tag() == TD_INTERFACE_IS_TYPE || Tag() == TD_LEGACY_ARRAY ||
+ Tag() == TD_PSTRING_SIZE_IS || Tag() == TD_PWSTRING_SIZE_IS;
+ }
+
+ // Unwrap a nested type to its innermost value (e.g. through arrays).
+ const nsXPTType& InnermostType() const {
+ if (Tag() == TD_LEGACY_ARRAY || Tag() == TD_ARRAY) {
+ return ArrayElementType().InnermostType();
+ }
+ return *this;
+ }
+
+ // In-memory size of native type in bytes.
+ inline size_t Stride() const;
+
+ // Offset the given base pointer to reference the element at the given index.
+ void* ElementPtr(const void* aBase, uint32_t aIndex) const {
+ return (char*)aBase + (aIndex * Stride());
+ }
+
+ // Zero out a native value of the given type. The type must not be 'complex'.
+ void ZeroValue(void* aValue) const {
+ MOZ_RELEASE_ASSERT(!IsComplex(), "Cannot zero a complex value");
+ memset(aValue, 0, Stride());
+ }
+
+ // Indexes into the extra types array of a small set of known types.
+ enum class Idx : uint8_t {
+ INT8 = 0,
+ UINT8,
+ INT16,
+ UINT16,
+ INT32,
+ UINT32,
+ INT64,
+ UINT64,
+ FLOAT,
+ DOUBLE,
+ BOOL,
+ CHAR,
+ WCHAR,
+ NSIDPTR,
+ PSTRING,
+ PWSTRING,
+ INTERFACE_IS_TYPE
+ };
+
+ // Helper methods for fabricating nsXPTType values used by xpconnect.
+ static nsXPTType MkArrayType(Idx aInner) {
+ MOZ_ASSERT(aInner <= Idx::INTERFACE_IS_TYPE);
+ return {TD_LEGACY_ARRAY, false, false, false, 0, (uint8_t)aInner};
+ }
+ static const nsXPTType& Get(Idx aInner) {
+ MOZ_ASSERT(aInner <= Idx::INTERFACE_IS_TYPE);
+ return xpt::detail::GetType((uint8_t)aInner);
+ }
+
+ ///////////////////////////////////////
+ // nsXPTType backwards compatibility //
+ ///////////////////////////////////////
+
+ nsXPTType& operator=(nsXPTTypeTag aPrefix) {
+ mTag = aPrefix;
+ return *this;
+ }
+ operator nsXPTTypeTag() const { return Tag(); }
+
+#define TD_ALIAS_(name_, value_) static constexpr nsXPTTypeTag name_ = value_
+ TD_ALIAS_(T_I8, TD_INT8);
+ TD_ALIAS_(T_I16, TD_INT16);
+ TD_ALIAS_(T_I32, TD_INT32);
+ TD_ALIAS_(T_I64, TD_INT64);
+ TD_ALIAS_(T_U8, TD_UINT8);
+ TD_ALIAS_(T_U16, TD_UINT16);
+ TD_ALIAS_(T_U32, TD_UINT32);
+ TD_ALIAS_(T_U64, TD_UINT64);
+ TD_ALIAS_(T_FLOAT, TD_FLOAT);
+ TD_ALIAS_(T_DOUBLE, TD_DOUBLE);
+ TD_ALIAS_(T_BOOL, TD_BOOL);
+ TD_ALIAS_(T_CHAR, TD_CHAR);
+ TD_ALIAS_(T_WCHAR, TD_WCHAR);
+ TD_ALIAS_(T_VOID, TD_VOID);
+ TD_ALIAS_(T_NSIDPTR, TD_NSIDPTR);
+ TD_ALIAS_(T_CHAR_STR, TD_PSTRING);
+ TD_ALIAS_(T_WCHAR_STR, TD_PWSTRING);
+ TD_ALIAS_(T_INTERFACE, TD_INTERFACE_TYPE);
+ TD_ALIAS_(T_INTERFACE_IS, TD_INTERFACE_IS_TYPE);
+ TD_ALIAS_(T_LEGACY_ARRAY, TD_LEGACY_ARRAY);
+ TD_ALIAS_(T_PSTRING_SIZE_IS, TD_PSTRING_SIZE_IS);
+ TD_ALIAS_(T_PWSTRING_SIZE_IS, TD_PWSTRING_SIZE_IS);
+ TD_ALIAS_(T_UTF8STRING, TD_UTF8STRING);
+ TD_ALIAS_(T_CSTRING, TD_CSTRING);
+ TD_ALIAS_(T_ASTRING, TD_ASTRING);
+ TD_ALIAS_(T_NSID, TD_NSID);
+ TD_ALIAS_(T_JSVAL, TD_JSVAL);
+ TD_ALIAS_(T_DOMOBJECT, TD_DOMOBJECT);
+ TD_ALIAS_(T_PROMISE, TD_PROMISE);
+ TD_ALIAS_(T_ARRAY, TD_ARRAY);
+#undef TD_ALIAS_
+
+ ////////////////////////////////////////////////////////////////
+ // Ensure these fields are in the same order as xptcodegen.py //
+ ////////////////////////////////////////////////////////////////
+
+ uint8_t mTag : 5;
+
+ // Parameter bitflags are packed into the XPTTypeDescriptor to save space.
+ // When the TypeDescriptor is not in a parameter, these flags are ignored.
+ uint8_t mInParam : 1;
+ uint8_t mOutParam : 1;
+ uint8_t mOptionalParam : 1;
+
+ // The data for the different variants is stored in these two data fields.
+ // These should only be accessed via the getter methods above, which will
+ // assert if the tag is invalid.
+ uint8_t mData1;
+ uint8_t mData2;
+};
+
+// The fields in nsXPTType were carefully ordered to minimize size.
+static_assert(sizeof(nsXPTType) == 3, "wrong size");
+
+/*
+ * A nsXPTParamInfo is used to describe either a single argument to a method or
+ * a method's result. It stores its flags in the type descriptor to save space.
+ */
+struct nsXPTParamInfo {
+ bool IsIn() const { return mType.mInParam; }
+ bool IsOut() const { return mType.mOutParam; }
+ bool IsOptional() const { return mType.mOptionalParam; }
+ bool IsShared() const { return false; } // XXX remove (backcompat)
+
+ // Get the type of this parameter.
+ const nsXPTType& Type() const { return mType; }
+ const nsXPTType& GetType() const {
+ return Type();
+ } // XXX remove (backcompat)
+
+ // Whether this parameter is passed indirectly on the stack. All out/inout
+ // params are passed indirectly, and complex types are always passed
+ // indirectly.
+ bool IsIndirect() const { return IsOut() || Type().IsComplex(); }
+
+ ////////////////////////////////////////////////////////////////
+ // Ensure these fields are in the same order as xptcodegen.py //
+ ////////////////////////////////////////////////////////////////
+
+ nsXPTType mType;
+};
+
+// The fields in nsXPTParamInfo were carefully ordered to minimize size.
+static_assert(sizeof(nsXPTParamInfo) == 3, "wrong size");
+
+/*
+ * A nsXPTMethodInfo is used to describe a single interface method.
+ */
+struct nsXPTMethodInfo {
+ bool IsGetter() const { return mGetter; }
+ bool IsSetter() const { return mSetter; }
+ bool IsReflectable() const { return mReflectable; }
+ bool IsSymbol() const { return mIsSymbol; }
+ bool WantsOptArgc() const { return mOptArgc; }
+ bool WantsContext() const { return mContext; }
+ uint8_t ParamCount() const { return mNumParams; }
+
+ const char* Name() const {
+ MOZ_ASSERT(!IsSymbol());
+ return xpt::detail::GetString(mName);
+ }
+ const nsXPTParamInfo& Param(uint8_t aIndex) const {
+ MOZ_ASSERT(aIndex < mNumParams);
+ return xpt::detail::GetParam(mParams + aIndex);
+ }
+
+ bool HasRetval() const { return mHasRetval; }
+ const nsXPTParamInfo* GetRetval() const {
+ return mHasRetval ? &Param(mNumParams - 1) : nullptr;
+ }
+
+ // If this is an [implicit_jscontext] method, returns the index of the
+ // implicit JSContext* argument in the C++ method's argument list.
+ // Otherwise returns UINT8_MAX.
+ uint8_t IndexOfJSContext() const {
+ if (!WantsContext()) {
+ return UINT8_MAX;
+ }
+ if (IsGetter() || IsSetter()) {
+ // Getters/setters always have the context as first argument.
+ return 0;
+ }
+ // The context comes before the return value, if there is one.
+ MOZ_ASSERT_IF(HasRetval(), ParamCount() > 0);
+ return ParamCount() - uint8_t(HasRetval());
+ }
+
+ JS::SymbolCode GetSymbolCode() const {
+ MOZ_ASSERT(IsSymbol());
+ return JS::SymbolCode(mName);
+ }
+
+ JS::Symbol* GetSymbol(JSContext* aCx) const {
+ return JS::GetWellKnownSymbol(aCx, GetSymbolCode());
+ }
+
+ const char* SymbolDescription() const;
+
+ const char* NameOrDescription() const {
+ if (IsSymbol()) {
+ return SymbolDescription();
+ }
+ return Name();
+ }
+
+ bool GetId(JSContext* aCx, jsid& aId) const;
+
+ /////////////////////////////////////////////
+ // nsXPTMethodInfo backwards compatibility //
+ /////////////////////////////////////////////
+
+ const char* GetName() const { return Name(); }
+
+ uint8_t GetParamCount() const { return ParamCount(); }
+ const nsXPTParamInfo& GetParam(uint8_t aIndex) const { return Param(aIndex); }
+
+ ////////////////////////////////////////////////////////////////
+ // Ensure these fields are in the same order as xptcodegen.py //
+ ////////////////////////////////////////////////////////////////
+
+ uint32_t mName; // Index into xpt::detail::sStrings.
+ uint16_t mParams; // Index into xpt::detail::sParams.
+ uint8_t mNumParams;
+
+ uint8_t mGetter : 1;
+ uint8_t mSetter : 1;
+ uint8_t mReflectable : 1;
+ uint8_t mOptArgc : 1;
+ uint8_t mContext : 1;
+ uint8_t mHasRetval : 1;
+ uint8_t mIsSymbol : 1;
+};
+
+// The fields in nsXPTMethodInfo were carefully ordered to minimize size.
+static_assert(sizeof(nsXPTMethodInfo) == 8, "wrong size");
+
+// This number is chosen to be no larger than the maximum number of parameters
+// any XPIDL-defined function needs; there is a static assert in the generated
+// code from xptcodegen.py to verify that decision. It is therefore also the
+// maximum number of stack allocated nsXPTCMiniVariant structures for argument
+// passing purposes in PrepareAndDispatch implementations.
+#if defined(MOZ_THUNDERBIRD) || defined(MOZ_SUITE)
+# define PARAM_BUFFER_COUNT 18
+#else
+# define PARAM_BUFFER_COUNT 14
+#endif
+
+/**
+ * A nsXPTConstantInfo is used to describe a single interface constant.
+ */
+struct nsXPTConstantInfo {
+ const char* Name() const { return xpt::detail::GetString(mName); }
+
+ JS::Value JSValue() const {
+ if (mSigned || mValue <= uint32_t(INT32_MAX)) {
+ return JS::Int32Value(int32_t(mValue));
+ }
+ return JS::DoubleValue(mValue);
+ }
+
+ ////////////////////////////////////////////////////////////////
+ // Ensure these fields are in the same order as xptcodegen.py //
+ ////////////////////////////////////////////////////////////////
+
+ uint32_t mName : 31; // Index into xpt::detail::mStrings.
+
+ // Whether the value should be interpreted as a int32_t or uint32_t.
+ uint32_t mSigned : 1;
+ uint32_t mValue; // The value stored as a u32
+};
+
+// The fields in nsXPTConstantInfo were carefully ordered to minimize size.
+static_assert(sizeof(nsXPTConstantInfo) == 8, "wrong size");
+
+/**
+ * Object representing the information required to wrap and unwrap DOMObjects.
+ *
+ * This object will not live in rodata as it contains relocations.
+ */
+struct nsXPTDOMObjectInfo {
+ nsresult Unwrap(JS::Handle<JS::Value> aHandle, void** aObj,
+ JSContext* aCx) const {
+ return mUnwrap(aHandle, aObj, aCx);
+ }
+
+ bool Wrap(JSContext* aCx, void* aObj,
+ JS::MutableHandle<JS::Value> aHandle) const {
+ return mWrap(aCx, aObj, aHandle);
+ }
+
+ void Cleanup(void* aObj) const { return mCleanup(aObj); }
+
+ ////////////////////////////////////////////////////////////////
+ // Ensure these fields are in the same order as xptcodegen.py //
+ ////////////////////////////////////////////////////////////////
+
+ nsresult (*mUnwrap)(JS::Handle<JS::Value> aHandle, void** aObj,
+ JSContext* aCx);
+ bool (*mWrap)(JSContext* aCx, void* aObj,
+ JS::MutableHandle<JS::Value> aHandle);
+ void (*mCleanup)(void* aObj);
+};
+
+namespace xpt {
+namespace detail {
+
+// The UntypedTArray type allows low-level access from XPConnect to nsTArray
+// internals without static knowledge of the array element type in question.
+class UntypedTArray : public nsTArray_base<nsTArrayFallibleAllocator,
+ nsTArray_RelocateUsingMemutils> {
+ public:
+ void* Elements() const { return static_cast<void*>(Hdr() + 1); }
+
+ // Changes the length and capacity to be at least large enough for aTo
+ // elements.
+ bool SetLength(const nsXPTType& aEltTy, uint32_t aTo) {
+ if (!EnsureCapacity<nsTArrayFallibleAllocator>(aTo, aEltTy.Stride())) {
+ return false;
+ }
+
+ if (mHdr != EmptyHdr()) {
+ mHdr->mLength = aTo;
+ }
+
+ return true;
+ }
+
+ // Free backing memory for the nsTArray object.
+ void Clear() {
+ if (mHdr != EmptyHdr() && !UsesAutoArrayBuffer()) {
+ nsTArrayFallibleAllocator::Free(mHdr);
+ }
+ mHdr = EmptyHdr();
+ }
+};
+
+//////////////////////////////////////////////
+// Raw typelib data stored in const statics //
+//////////////////////////////////////////////
+
+// XPIDL information
+extern const nsXPTInterfaceInfo sInterfaces[];
+extern const nsXPTType sTypes[];
+extern const nsXPTParamInfo sParams[];
+extern const nsXPTMethodInfo sMethods[];
+extern const nsXPTConstantInfo sConsts[];
+extern const nsXPTDOMObjectInfo sDOMObjects[];
+
+extern const char sStrings[];
+
+//////////////////////////////////////
+// Helper Methods for fetching data //
+//////////////////////////////////////
+
+inline const nsXPTInterfaceInfo* GetInterface(uint16_t aIndex) {
+ if (aIndex > 0 && aIndex <= sInterfacesSize) {
+ return &sInterfaces[aIndex - 1]; // 1-based as 0 is a marker.
+ }
+ return nullptr;
+}
+
+inline const nsXPTType& GetType(uint16_t aIndex) { return sTypes[aIndex]; }
+
+inline const nsXPTParamInfo& GetParam(uint16_t aIndex) {
+ return sParams[aIndex];
+}
+
+inline const nsXPTMethodInfo& GetMethod(uint16_t aIndex) {
+ return sMethods[aIndex];
+}
+
+inline const nsXPTConstantInfo& GetConstant(uint16_t aIndex) {
+ return sConsts[aIndex];
+}
+
+inline const nsXPTDOMObjectInfo& GetDOMObjectInfo(uint16_t aIndex) {
+ return sDOMObjects[aIndex];
+}
+
+inline const char* GetString(uint32_t aIndex) { return &sStrings[aIndex]; }
+
+} // namespace detail
+} // namespace xpt
+
+#define XPT_FOR_EACH_ARITHMETIC_TYPE(MACRO) \
+ MACRO(TD_INT8, int8_t) \
+ MACRO(TD_INT16, int16_t) \
+ MACRO(TD_INT32, int32_t) \
+ MACRO(TD_INT64, int64_t) \
+ MACRO(TD_UINT8, uint8_t) \
+ MACRO(TD_UINT16, uint16_t) \
+ MACRO(TD_UINT32, uint32_t) \
+ MACRO(TD_UINT64, uint64_t) \
+ MACRO(TD_FLOAT, float) \
+ MACRO(TD_DOUBLE, double) \
+ MACRO(TD_BOOL, bool) \
+ MACRO(TD_CHAR, char) \
+ MACRO(TD_WCHAR, char16_t)
+
+#define XPT_FOR_EACH_POINTER_TYPE(MACRO) \
+ MACRO(TD_VOID, void*) \
+ MACRO(TD_NSIDPTR, nsID*) \
+ MACRO(TD_PSTRING, char*) \
+ MACRO(TD_PWSTRING, wchar_t*) \
+ MACRO(TD_INTERFACE_TYPE, nsISupports*) \
+ MACRO(TD_INTERFACE_IS_TYPE, nsISupports*) \
+ MACRO(TD_LEGACY_ARRAY, void*) \
+ MACRO(TD_PSTRING_SIZE_IS, char*) \
+ MACRO(TD_PWSTRING_SIZE_IS, wchar_t*) \
+ MACRO(TD_DOMOBJECT, void*) \
+ MACRO(TD_PROMISE, mozilla::dom::Promise*)
+
+#define XPT_FOR_EACH_COMPLEX_TYPE(MACRO) \
+ MACRO(TD_UTF8STRING, nsCString) \
+ MACRO(TD_CSTRING, nsCString) \
+ MACRO(TD_ASTRING, nsString) \
+ MACRO(TD_NSID, nsID) \
+ MACRO(TD_JSVAL, JS::Value) \
+ MACRO(TD_ARRAY, xpt::detail::UntypedTArray)
+
+#define XPT_FOR_EACH_TYPE(MACRO) \
+ XPT_FOR_EACH_ARITHMETIC_TYPE(MACRO) \
+ XPT_FOR_EACH_POINTER_TYPE(MACRO) \
+ XPT_FOR_EACH_COMPLEX_TYPE(MACRO)
+
+inline size_t nsXPTType::Stride() const {
+ // Compute the stride to use when walking an array of the given type.
+ switch (Tag()) {
+#define XPT_TYPE_STRIDE(tag, type) \
+ case tag: \
+ return sizeof(type);
+ XPT_FOR_EACH_TYPE(XPT_TYPE_STRIDE)
+#undef XPT_TYPE_STRIDE
+ }
+
+ MOZ_CRASH("Unknown type");
+}
+
+#endif /* xptinfo_h */