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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
tree | f435a8308119effd964b339f76abb83a57c29483 /dom/ipc/TabContext.h | |
parent | Initial commit. (diff) | |
download | firefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz firefox-26a029d407be480d791972afb5975cf62c9360a6.zip |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'dom/ipc/TabContext.h')
-rw-r--r-- | dom/ipc/TabContext.h | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/dom/ipc/TabContext.h b/dom/ipc/TabContext.h new file mode 100644 index 0000000000..00bf69c2a2 --- /dev/null +++ b/dom/ipc/TabContext.h @@ -0,0 +1,171 @@ +/* -*- 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 http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_dom_TabContext_h +#define mozilla_dom_TabContext_h + +#include "nsCOMPtr.h" +#include "mozilla/BasePrincipal.h" +#include "nsPIDOMWindow.h" +#include "nsPIWindowRoot.h" + +namespace mozilla::dom { + +class IPCTabContext; + +/** + * TabContext encapsulates information about an iframe. + * + * BrowserParent and BrowserChild both inherit from TabContext, and you can also + * have standalone TabContext objects. + * + * This class is immutable except by calling one of the protected + * SetTabContext*() methods (and those methods can only be called once). See + * also MutableTabContext. + */ +class TabContext { + public: + TabContext(); + + /* (The implicit copy-constructor and operator= are fine.) */ + + /** + * Generates IPCTabContext of type BrowserFrameIPCTabContext from this + * TabContext's information. + */ + IPCTabContext AsIPCTabContext() const; + + uint64_t ChromeOuterWindowID() const; + + uint32_t MaxTouchPoints() const { return mMaxTouchPoints; } + + protected: + friend class MaybeInvalidTabContext; + + /** + * These protected mutator methods let you modify a TabContext once. Further + * attempts to modify a given TabContext will fail (the method will return + * false). + * + * These mutators will also fail if the TabContext was created with anything + * other than the no-args constructor. + */ + + /** + * Set this TabContext to match the given TabContext. + */ + bool SetTabContext(const TabContext& aContext); + + bool SetTabContext(uint64_t aChromeOuterWindowID, uint32_t aMaxTouchPoints); + + /** + * Modify this TabContext to match the given TabContext. This is a special + * case triggered by nsFrameLoader::SwapWithOtherRemoteLoader which may have + * caused the owner content to change. + * + * This special case only allows the field `mChromeOuterWindowID` to be + * changed. If any other fields have changed, the update is ignored and + * returns false. + */ + bool UpdateTabContextAfterSwap(const TabContext& aContext); + + void SetMaxTouchPoints(uint32_t aMaxTouchPoints) { + mMaxTouchPoints = aMaxTouchPoints; + } + + private: + /** + * Has this TabContext been initialized? If so, mutator methods will fail. + */ + bool mInitialized; + + /** + * The outerWindowID of the window hosting the remote frameloader. + */ + uint64_t mChromeOuterWindowID; + + /** + * Maximum number of touch points. + */ + uint32_t mMaxTouchPoints; +}; + +/** + * MutableTabContext is the same as MaybeInvalidTabContext, except the mutation + * methods are public instead of protected. You can still only call these + * mutation methods once on a given object. + */ +class MutableTabContext : public TabContext { + public: + bool SetTabContext(const TabContext& aContext) { + return TabContext::SetTabContext(aContext); + } + + bool SetTabContext(uint64_t aChromeOuterWindowID, uint32_t aMaxTouchPoints) { + return TabContext::SetTabContext(aChromeOuterWindowID, aMaxTouchPoints); + } +}; + +/** + * MaybeInvalidTabContext is a simple class that lets you transform an + * IPCTabContext into a TabContext. + * + * The issue is that an IPCTabContext is not necessarily valid. So to convert + * an IPCTabContext into a TabContext, you construct a MaybeInvalidTabContext, + * check whether it's valid, and, if so, read out your TabContext. + * + * Example usage: + * + * void UseTabContext(const TabContext& aTabContext); + * + * void CreateTab(const IPCTabContext& aContext) { + * MaybeInvalidTabContext tc(aContext); + * if (!tc.IsValid()) { + * NS_ERROR(nsPrintfCString("Got an invalid IPCTabContext: %s", + * tc.GetInvalidReason())); + * return; + * } + * UseTabContext(tc.GetTabContext()); + * } + */ +class MaybeInvalidTabContext { + public: + /** + * This constructor copies the information in aContext and sets IsValid() as + * appropriate. + */ + explicit MaybeInvalidTabContext(const IPCTabContext& aContext); + + /** + * Was the IPCTabContext we received in our constructor valid? + */ + bool IsValid(); + + /** + * If IsValid(), this function returns null. Otherwise, it returns a + * human-readable string indicating why the IPCTabContext passed to our + * constructor was not valid. + */ + const char* GetInvalidReason(); + + /** + * If IsValid(), this function returns a reference to a TabContext + * corresponding to the IPCTabContext passed to our constructor. If + * !IsValid(), this function crashes. + */ + const TabContext& GetTabContext(); + + private: + MaybeInvalidTabContext(const MaybeInvalidTabContext&) = delete; + MaybeInvalidTabContext& operator=(const MaybeInvalidTabContext&) = delete; + + const char* mInvalidReason; + MutableTabContext mTabContext; +}; + +} // namespace mozilla::dom + +#endif |