kwin/src/client_machine.h

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2020-08-02 22:22:19 +00:00
/*
KWin - the KDE window manager
This file is part of the KDE project.
Improved resolving whether a window is on local machine Most windows use the hostname in WM_CLIENT_MACHINE, but there are windows using the FQDN (for example libreoffice). So instead of "foo" it is "foo.local.net" or similar. The logic so far has been unable to properly determine whether windows with FQDN are on the local system. In order to solve this problem the handling is split out into an own class which stores the information of hostname and whether it is a local machine. This is to not query multiple times. To determine whether the Client is on the local system getaddrinfo is used for the own hostname and the FQDN provided in WM_CLIENT_MACHINE. If one of the queried names matches, we know that it is on the local machine. The old logic to compare the hostname is still used and getaddrinfo is only a fallback in case hostname does not match. The problem with getaddrinfo is, that it accesses the network and by that could block. To circumvent this problem the calls are moved into threads by using QtConcurrent::run. Obviously this brings disadvantages. When trying to resolve whether a Client is on the local machine and a FQDN is used, the information is initially wrong. The new ClientMachine class emits a signal when the information that the system is local becomes available, but for some things this is just too late: * window rules are already gathered * Session Management has already taken place In both cases this is an acceptable loss. For window rules it just needs a proper matching of the machine in case of localhost (remote hosts are not affected). And the case of session management is very academic as it is unlikely that a restoring session contains remote windows. BUG: 308391 FIXED-IN: 4.11 REVIEW: 108235
2013-01-07 07:07:27 +00:00
2020-08-02 22:22:19 +00:00
SPDX-FileCopyrightText: 2013 Martin Gräßlin <mgraesslin@kde.org>
Improved resolving whether a window is on local machine Most windows use the hostname in WM_CLIENT_MACHINE, but there are windows using the FQDN (for example libreoffice). So instead of "foo" it is "foo.local.net" or similar. The logic so far has been unable to properly determine whether windows with FQDN are on the local system. In order to solve this problem the handling is split out into an own class which stores the information of hostname and whether it is a local machine. This is to not query multiple times. To determine whether the Client is on the local system getaddrinfo is used for the own hostname and the FQDN provided in WM_CLIENT_MACHINE. If one of the queried names matches, we know that it is on the local machine. The old logic to compare the hostname is still used and getaddrinfo is only a fallback in case hostname does not match. The problem with getaddrinfo is, that it accesses the network and by that could block. To circumvent this problem the calls are moved into threads by using QtConcurrent::run. Obviously this brings disadvantages. When trying to resolve whether a Client is on the local machine and a FQDN is used, the information is initially wrong. The new ClientMachine class emits a signal when the information that the system is local becomes available, but for some things this is just too late: * window rules are already gathered * Session Management has already taken place In both cases this is an acceptable loss. For window rules it just needs a proper matching of the machine in case of localhost (remote hosts are not affected). And the case of session management is very academic as it is unlikely that a restoring session contains remote windows. BUG: 308391 FIXED-IN: 4.11 REVIEW: 108235
2013-01-07 07:07:27 +00:00
2020-08-02 22:22:19 +00:00
SPDX-License-Identifier: GPL-2.0-or-later
*/
Improved resolving whether a window is on local machine Most windows use the hostname in WM_CLIENT_MACHINE, but there are windows using the FQDN (for example libreoffice). So instead of "foo" it is "foo.local.net" or similar. The logic so far has been unable to properly determine whether windows with FQDN are on the local system. In order to solve this problem the handling is split out into an own class which stores the information of hostname and whether it is a local machine. This is to not query multiple times. To determine whether the Client is on the local system getaddrinfo is used for the own hostname and the FQDN provided in WM_CLIENT_MACHINE. If one of the queried names matches, we know that it is on the local machine. The old logic to compare the hostname is still used and getaddrinfo is only a fallback in case hostname does not match. The problem with getaddrinfo is, that it accesses the network and by that could block. To circumvent this problem the calls are moved into threads by using QtConcurrent::run. Obviously this brings disadvantages. When trying to resolve whether a Client is on the local machine and a FQDN is used, the information is initially wrong. The new ClientMachine class emits a signal when the information that the system is local becomes available, but for some things this is just too late: * window rules are already gathered * Session Management has already taken place In both cases this is an acceptable loss. For window rules it just needs a proper matching of the machine in case of localhost (remote hosts are not affected). And the case of session management is very academic as it is unlikely that a restoring session contains remote windows. BUG: 308391 FIXED-IN: 4.11 REVIEW: 108235
2013-01-07 07:07:27 +00:00
#ifndef KWIN_CLIENT_MACHINE_H
#define KWIN_CLIENT_MACHINE_H
#include <QObject>
#include <xcb/xcb.h>
// forward declaration
struct addrinfo;
template <typename T>
class QFutureWatcher;
namespace KWin {
class GetAddrInfo : public QObject
{
Q_OBJECT
public:
explicit GetAddrInfo(const QByteArray &hostName, QObject *parent = nullptr);
Run clang-tidy with modernize-use-override check Summary: Currently code base of kwin can be viewed as two pieces. One is very ancient, and the other one is more modern, which uses new C++ features. The main problem with the ancient code is that it was written before C++11 era. So, no override or final keywords, lambdas, etc. Quite recently, KDE compiler settings were changed to show a warning if a virtual method has missing override keyword. As you might have already guessed, this fired back at us because of that ancient code. We had about 500 new compiler warnings. A "solution" was proposed to that problem - disable -Wno-suggest-override and the other similar warning for clang. It's hard to call a solution because those warnings are disabled not only for the old code, but also for new. This is not what we want! The main argument for not actually fixing the problem was that git history will be screwed as well because of human factor. While good git history is a very important thing, we should not go crazy about it and block every change that somehow alters git history. git blame allows to specify starting revision for a reason. The other argument (human factor) can be easily solved by using tools such as clang-tidy. clang-tidy is a clang-based linter for C++. It can be used for various things, e.g. fixing coding style(e.g. add missing braces to if statements, readability-braces-around-statements check), or in our case add missing override keywords. Test Plan: Compiles. Reviewers: #kwin, davidedmundson Reviewed By: #kwin, davidedmundson Subscribers: davidedmundson, apol, romangg, kwin Tags: #kwin Differential Revision: https://phabricator.kde.org/D22371
2019-07-22 16:52:26 +00:00
~GetAddrInfo() override;
Improved resolving whether a window is on local machine Most windows use the hostname in WM_CLIENT_MACHINE, but there are windows using the FQDN (for example libreoffice). So instead of "foo" it is "foo.local.net" or similar. The logic so far has been unable to properly determine whether windows with FQDN are on the local system. In order to solve this problem the handling is split out into an own class which stores the information of hostname and whether it is a local machine. This is to not query multiple times. To determine whether the Client is on the local system getaddrinfo is used for the own hostname and the FQDN provided in WM_CLIENT_MACHINE. If one of the queried names matches, we know that it is on the local machine. The old logic to compare the hostname is still used and getaddrinfo is only a fallback in case hostname does not match. The problem with getaddrinfo is, that it accesses the network and by that could block. To circumvent this problem the calls are moved into threads by using QtConcurrent::run. Obviously this brings disadvantages. When trying to resolve whether a Client is on the local machine and a FQDN is used, the information is initially wrong. The new ClientMachine class emits a signal when the information that the system is local becomes available, but for some things this is just too late: * window rules are already gathered * Session Management has already taken place In both cases this is an acceptable loss. For window rules it just needs a proper matching of the machine in case of localhost (remote hosts are not affected). And the case of session management is very academic as it is unlikely that a restoring session contains remote windows. BUG: 308391 FIXED-IN: 4.11 REVIEW: 108235
2013-01-07 07:07:27 +00:00
void resolve();
Q_SIGNALS:
void local();
private Q_SLOTS:
void slotResolved();
void slotOwnAddressResolved();
private:
void compare();
bool resolved(QFutureWatcher<int> *watcher);
bool m_resolving;
bool m_resolved;
bool m_ownResolved;
QByteArray m_hostName;
addrinfo *m_addressHints;
addrinfo *m_address;
addrinfo *m_ownAddress;
QFutureWatcher<int> *m_watcher;
QFutureWatcher<int> *m_ownAddressWatcher;
};
class ClientMachine : public QObject
{
Q_OBJECT
public:
explicit ClientMachine(QObject *parent = nullptr);
Run clang-tidy with modernize-use-override check Summary: Currently code base of kwin can be viewed as two pieces. One is very ancient, and the other one is more modern, which uses new C++ features. The main problem with the ancient code is that it was written before C++11 era. So, no override or final keywords, lambdas, etc. Quite recently, KDE compiler settings were changed to show a warning if a virtual method has missing override keyword. As you might have already guessed, this fired back at us because of that ancient code. We had about 500 new compiler warnings. A "solution" was proposed to that problem - disable -Wno-suggest-override and the other similar warning for clang. It's hard to call a solution because those warnings are disabled not only for the old code, but also for new. This is not what we want! The main argument for not actually fixing the problem was that git history will be screwed as well because of human factor. While good git history is a very important thing, we should not go crazy about it and block every change that somehow alters git history. git blame allows to specify starting revision for a reason. The other argument (human factor) can be easily solved by using tools such as clang-tidy. clang-tidy is a clang-based linter for C++. It can be used for various things, e.g. fixing coding style(e.g. add missing braces to if statements, readability-braces-around-statements check), or in our case add missing override keywords. Test Plan: Compiles. Reviewers: #kwin, davidedmundson Reviewed By: #kwin, davidedmundson Subscribers: davidedmundson, apol, romangg, kwin Tags: #kwin Differential Revision: https://phabricator.kde.org/D22371
2019-07-22 16:52:26 +00:00
~ClientMachine() override;
Improved resolving whether a window is on local machine Most windows use the hostname in WM_CLIENT_MACHINE, but there are windows using the FQDN (for example libreoffice). So instead of "foo" it is "foo.local.net" or similar. The logic so far has been unable to properly determine whether windows with FQDN are on the local system. In order to solve this problem the handling is split out into an own class which stores the information of hostname and whether it is a local machine. This is to not query multiple times. To determine whether the Client is on the local system getaddrinfo is used for the own hostname and the FQDN provided in WM_CLIENT_MACHINE. If one of the queried names matches, we know that it is on the local machine. The old logic to compare the hostname is still used and getaddrinfo is only a fallback in case hostname does not match. The problem with getaddrinfo is, that it accesses the network and by that could block. To circumvent this problem the calls are moved into threads by using QtConcurrent::run. Obviously this brings disadvantages. When trying to resolve whether a Client is on the local machine and a FQDN is used, the information is initially wrong. The new ClientMachine class emits a signal when the information that the system is local becomes available, but for some things this is just too late: * window rules are already gathered * Session Management has already taken place In both cases this is an acceptable loss. For window rules it just needs a proper matching of the machine in case of localhost (remote hosts are not affected). And the case of session management is very academic as it is unlikely that a restoring session contains remote windows. BUG: 308391 FIXED-IN: 4.11 REVIEW: 108235
2013-01-07 07:07:27 +00:00
void resolve(xcb_window_t window, xcb_window_t clientLeader);
const QByteArray &hostName() const;
bool isLocal() const;
static QByteArray localhost();
bool isResolving() const;
Q_SIGNALS:
void localhostChanged();
private Q_SLOTS:
void setLocal();
void resolveFinished();
private:
void checkForLocalhost();
QByteArray m_hostName;
bool m_localhost;
bool m_resolved;
bool m_resolving;
};
inline
bool ClientMachine::isLocal() const
{
return m_localhost;
}
inline
const QByteArray &ClientMachine::hostName() const
{
return m_hostName;
}
inline
QByteArray ClientMachine::localhost()
{
return "localhost";
}
inline
bool ClientMachine::isResolving() const
{
return m_resolving;
}
} // namespace
#endif