From 9e3c08db40b8916968b9f30096c7be3f00ce9647 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 21 Apr 2024 13:44:51 +0200 Subject: Adding upstream version 1:115.7.0. Signed-off-by: Daniel Baumann --- gfx/2d/UserData.h | 214 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 214 insertions(+) create mode 100644 gfx/2d/UserData.h (limited to 'gfx/2d/UserData.h') diff --git a/gfx/2d/UserData.h b/gfx/2d/UserData.h new file mode 100644 index 0000000000..16a7db343e --- /dev/null +++ b/gfx/2d/UserData.h @@ -0,0 +1,214 @@ +/* -*- 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_GFX_USERDATA_H_ +#define MOZILLA_GFX_USERDATA_H_ + +#include +#include "Types.h" +#include "mozilla/Assertions.h" +#include "mozilla/Atomics.h" +#include "mozilla/Mutex.h" + +namespace mozilla { +namespace gfx { + +struct UserDataKey { + int unused; +}; + +/* this class is basically a clone of the user data concept from cairo */ +class UserData { + public: + typedef void (*DestroyFunc)(void* data); + + UserData() : count(0), entries(nullptr) {} + + /* Attaches untyped userData associated with key. destroy is called on + * destruction */ + void Add(UserDataKey* key, void* userData, DestroyFunc destroy) { + for (int i = 0; i < count; i++) { + if (key == entries[i].key) { + if (entries[i].destroy) { + entries[i].destroy(entries[i].userData); + } + entries[i].userData = userData; + entries[i].destroy = destroy; + return; + } + } + + // We could keep entries in a std::vector instead of managing it by hand + // but that would propagate an stl dependency out which we'd rather not + // do (see bug 666609). Plus, the entries array is expect to stay small + // so doing a realloc everytime we add a new entry shouldn't be too costly + entries = + static_cast(realloc(entries, sizeof(Entry) * (count + 1))); + + if (!entries) { + MOZ_CRASH("GFX: UserData::Add"); + } + + entries[count].key = key; + entries[count].userData = userData; + entries[count].destroy = destroy; + + count++; + } + + /* Remove and return user data associated with key, without destroying it */ + void* Remove(UserDataKey* key) { + for (int i = 0; i < count; i++) { + if (key == entries[i].key) { + void* userData = entries[i].userData; + // decrement before looping so entries[i+1] doesn't read past the end: + --count; + for (; i < count; i++) { + entries[i] = entries[i + 1]; + } + return userData; + } + } + return nullptr; + } + + /* Remove and destroy a given key */ + void RemoveAndDestroy(UserDataKey* key) { + for (int i = 0; i < count; i++) { + if (key == entries[i].key) { + if (entries[i].destroy) { + entries[i].destroy(entries[i].userData); + } + // decrement before looping so entries[i+1] doesn't read past the end: + --count; + for (; i < count; i++) { + entries[i] = entries[i + 1]; + } + } + } + } + + /* Retrives the userData for the associated key */ + void* Get(UserDataKey* key) const { + for (int i = 0; i < count; i++) { + if (key == entries[i].key) { + return entries[i].userData; + } + } + return nullptr; + } + + bool Has(UserDataKey* key) { + for (int i = 0; i < count; i++) { + if (key == entries[i].key) { + return true; + } + } + return false; + } + + void Destroy() { + if (!entries) { + return; + } + for (int i = 0; i < count; i++) { + if (entries[i].destroy) { + entries[i].destroy(entries[i].userData); + } + } + free(entries); + entries = nullptr; + count = 0; + } + + ~UserData() { Destroy(); } + + private: + struct Entry { + const UserDataKey* key; + void* userData; + DestroyFunc destroy; + }; + + int count; + Entry* entries; +}; + +class ThreadSafeUserData { + protected: + struct LockedUserData : public UserData { + Mutex mLock; + + LockedUserData() : mLock("LockedUserData::mLock") {} + }; + + public: + ~ThreadSafeUserData() { + if (LockedUserData* userData = mUserData.exchange(nullptr)) { + { + MutexAutoLock lock(userData->mLock); + userData->Destroy(); + } + delete userData; + } + } + + void Add(UserDataKey* key, void* value, UserData::DestroyFunc destroy) { + LockedUserData* userData = GetUserData(); + MutexAutoLock lock(userData->mLock); + userData->Add(key, value, destroy); + } + + void* Remove(UserDataKey* key) { + LockedUserData* userData = GetUserData(); + MutexAutoLock lock(userData->mLock); + return userData->Remove(key); + } + + void RemoveAndDestroy(UserDataKey* key) { + LockedUserData* userData = GetUserData(); + MutexAutoLock lock(userData->mLock); + userData->RemoveAndDestroy(key); + } + + void* Get(UserDataKey* key) const { + LockedUserData* userData = GetUserData(); + MutexAutoLock lock(userData->mLock); + return userData->Get(key); + } + + bool Has(UserDataKey* key) { + LockedUserData* userData = GetUserData(); + MutexAutoLock lock(userData->mLock); + return userData->Has(key); + } + + private: + LockedUserData* GetUserData() const { + LockedUserData* userData = mUserData; + if (!userData) { + userData = new LockedUserData; + if (!mUserData.compareExchange(nullptr, userData)) { + delete userData; + userData = mUserData; + MOZ_ASSERT(userData); + } + } + return userData; + } + + // The Mutex class is quite large. For small, frequent classes (ScaledFont, + // SourceSurface, etc.) this can add a lot of memory overhead, especially if + // UserData is only infrequently used. To avoid this, we only allocate the + // LockedUserData if it is actually used. If unused, it only adds a single + // pointer as overhead. + mutable Atomic mUserData; +}; + +} // namespace gfx +} // namespace mozilla + +#endif /* MOZILLA_GFX_USERDATA_H_ */ -- cgit v1.2.3