From e07aec7eaa40361b685f35dd75b9f668f28364b7 Mon Sep 17 00:00:00 2001
From: Fabian Kosmale <fabian.kosmale@qt.io>
Date: Sun, 21 Mar 2021 10:54:55 +0100
Subject: [PATCH] QFuture: cleanup headers

Do not include vector; we currently do not use std::vector, and the plan
is to use QList when that one supports move-only types.
Use QMutexLocker instead of std::mutex_locker, considering that the
former is already included with <QMutex>.
Use forward declarations where applicable.
Add header which were currently only indirectly included (to make
QtCreator's code model happy).

Change-Id: I37d5cd3982047a6d8a3132fd66571878298039b3
Reviewed-by: Sona Kurazyan <sona.kurazyan@qt.io>
Reviewed-by: Karsten Heimrich <karsten.heimrich@qt.io>
---
 src/corelib/thread/qfuture.h            |  1 -
 src/corelib/thread/qfutureinterface.cpp |  5 ++++
 src/corelib/thread/qfutureinterface.h   | 31 ++++++++++++++-----------
 src/corelib/thread/qfutureinterface_p.h |  2 ++
 4 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/src/corelib/thread/qfuture.h b/src/corelib/thread/qfuture.h
index a56e9ee3ff7..9aa77ccf2f0 100644
--- a/src/corelib/thread/qfuture.h
+++ b/src/corelib/thread/qfuture.h
@@ -48,7 +48,6 @@
 #include <QtCore/qfuture_impl.h>
 
 #include <type_traits>
-#include <vector>
 
 QT_REQUIRE_CONFIG(future);
 
diff --git a/src/corelib/thread/qfutureinterface.cpp b/src/corelib/thread/qfutureinterface.cpp
index 7a8ba081030..4e9d557209a 100644
--- a/src/corelib/thread/qfutureinterface.cpp
+++ b/src/corelib/thread/qfutureinterface.cpp
@@ -600,6 +600,11 @@ void QFutureInterfaceBase::reset()
     d->isValid = false;
 }
 
+void QFutureInterfaceBase::rethrowPossibleException()
+{
+    exceptionStore().throwPossibleException();
+}
+
 QFutureInterfaceBasePrivate::QFutureInterfaceBasePrivate(QFutureInterfaceBase::State initialState)
     : refCount(1), m_progressValue(0), m_progressMinimum(0), m_progressMaximum(0),
       state(initialState),
diff --git a/src/corelib/thread/qfutureinterface.h b/src/corelib/thread/qfutureinterface.h
index 2432503cf79..62875c5ef9c 100644
--- a/src/corelib/thread/qfutureinterface.h
+++ b/src/corelib/thread/qfutureinterface.h
@@ -40,17 +40,19 @@
 #ifndef QFUTUREINTERFACE_H
 #define QFUTUREINTERFACE_H
 
-#include <QtCore/qrunnable.h>
 #include <QtCore/qmutex.h>
-#include <QtCore/qexception.h>
+#include <QtCore/QMutexLocker>
 #include <QtCore/qresultstore.h>
+#ifndef QT_NO_EXCEPTIONS
+#include <exception>
+#endif
 
 #include <utility>
-#include <vector>
-#include <mutex>
 
 QT_REQUIRE_CONFIG(future);
 
+QT_FORWARD_DECLARE_CLASS(QRunnable)
+QT_FORWARD_DECLARE_CLASS(QException)
 QT_BEGIN_NAMESPACE
 
 
@@ -64,6 +66,8 @@ namespace QtPrivate {
 template<typename Function, typename ResultType, typename ParentResultType>
 class Continuation;
 
+class ExceptionStore;
+
 template<class Function, class ResultType>
 class CanceledHandler;
 
@@ -169,6 +173,7 @@ protected:
     bool refT() const;
     bool derefT() const;
     void reset();
+    void rethrowPossibleException();
 public:
 
 #ifndef QFUTURE_TEST
@@ -262,7 +267,7 @@ public:
 template <typename T>
 inline bool QFutureInterface<T>::reportResult(const T *result, int index)
 {
-    std::lock_guard<QMutex> locker{mutex()};
+    QMutexLocker<QMutex> locker{&mutex()};
     if (this->queryState(Canceled) || this->queryState(Finished))
         return false;
 
@@ -283,7 +288,7 @@ inline bool QFutureInterface<T>::reportResult(const T *result, int index)
 template<typename T>
 bool QFutureInterface<T>::reportAndMoveResult(T &&result, int index)
 {
-    std::lock_guard<QMutex> locker{mutex()};
+    QMutexLocker<QMutex> locker{&mutex()};
     if (queryState(Canceled) || queryState(Finished))
         return false;
 
@@ -312,7 +317,7 @@ inline bool QFutureInterface<T>::reportResult(const T &result, int index)
 template<typename T>
 inline bool QFutureInterface<T>::reportResults(const QList<T> &_results, int beginIndex, int count)
 {
-    std::lock_guard<QMutex> locker{mutex()};
+    QMutexLocker<QMutex> locker{&mutex()};
     if (this->queryState(Canceled) || this->queryState(Finished))
         return false;
 
@@ -343,14 +348,14 @@ inline bool QFutureInterface<T>::reportFinished(const T *result)
 template <typename T>
 inline const T &QFutureInterface<T>::resultReference(int index) const
 {
-    std::lock_guard<QMutex> locker{mutex()};
+    QMutexLocker<QMutex> locker{&mutex()};
     return resultStoreBase().resultAt(index).template value<T>();
 }
 
 template <typename T>
 inline const T *QFutureInterface<T>::resultPointer(int index) const
 {
-    std::lock_guard<QMutex> locker{mutex()};
+    QMutexLocker<QMutex> locker{&mutex()};
     return resultStoreBase().resultAt(index).template pointer<T>();
 }
 
@@ -358,14 +363,14 @@ template <typename T>
 inline QList<T> QFutureInterface<T>::results()
 {
     if (this->isCanceled()) {
-        exceptionStore().throwPossibleException();
+        rethrowPossibleException();
         return QList<T>();
     }
 
     QFutureInterfaceBase::waitForResult(-1);
 
     QList<T> res;
-    std::lock_guard<QMutex> locker{mutex()};
+    QMutexLocker<QMutex> locker{&mutex()};
 
     QtPrivate::ResultIteratorBase it = resultStoreBase().begin();
     while (it != resultStoreBase().end()) {
@@ -385,7 +390,7 @@ T QFutureInterface<T>::takeResult()
     // not to mess with other unready results.
     waitForResult(-1);
 
-    const std::lock_guard<QMutex> locker{mutex()};
+    const QMutexLocker<QMutex> locker{&mutex()};
     QtPrivate::ResultIteratorBase position = resultStoreBase().resultAt(0);
     T ret(std::move_if_noexcept(position.value<T>()));
     reset();
@@ -404,7 +409,7 @@ std::vector<T> QFutureInterface<T>::takeResults()
     std::vector<T> res;
     res.reserve(resultCount());
 
-    const std::lock_guard<QMutex> locker{mutex()};
+    const QMutexLocker<QMutex> locker{&mutex()};
 
     QtPrivate::ResultIteratorBase it = resultStoreBase().begin();
     for (auto endIt = resultStoreBase().end(); it != endIt; ++it)
diff --git a/src/corelib/thread/qfutureinterface_p.h b/src/corelib/thread/qfutureinterface_p.h
index df71d3d4b66..28dc4be2633 100644
--- a/src/corelib/thread/qfutureinterface_p.h
+++ b/src/corelib/thread/qfutureinterface_p.h
@@ -58,6 +58,8 @@
 #include <QtCore/qwaitcondition.h>
 #include <QtCore/qrunnable.h>
 #include <QtCore/qthreadpool.h>
+#include <QtCore/qfutureinterface.h>
+#include <QtCore/qexception.h>
 
 QT_REQUIRE_CONFIG(future);