wasm: introduce qwasmglobal_p.h

Global helpers/utils for Q_OS_WASM.

Move the thread proxying functions to qwasmglobal_p.h,
and update calling code.

qtstweb_p.h now contains C++ wrappers for native web
API only. The proxying functions will be removed from
qeventdispatcher_wasm in a later commit.

Change-Id: I08a56c211b08929750970895b63ca48d4a07a0a1
Reviewed-by: Lorn Potter <[email protected]>

8 files changed, 144 insertions, 56 deletions

diff --git a/src/corelib/CMakeLists.txt b/src/corelib/CMakeLists.txt
index 8d0e60af9b9..68745591d2c 100644
--- a/src/corelib/CMakeLists.txt
+++ b/src/corelib/CMakeLists.txt
@@ -1440,6 +1440,7 @@ endif()
 
 qt_internal_extend_target(Core CONDITION WASM
     SOURCES
+        platform/wasm/qwasmglobal.cpp platform/wasm/qwasmglobal_p.h
         platform/wasm/qstdweb.cpp platform/wasm/qstdweb_p.h
         platform/wasm/qwasmsocket.cpp platform/wasm/qwasmsocket_p.h
         platform/wasm/qwasmsuspendresumecontrol.cpp platform/wasm/qwasmsuspendresumecontrol_p.h
diff --git a/src/corelib/io/qsettings_wasm.cpp b/src/corelib/io/qsettings_wasm.cpp
index 7d80ff82d37..72045a2d519 100644
--- a/src/corelib/io/qsettings_wasm.cpp
+++ b/src/corelib/io/qsettings_wasm.cpp
@@ -11,6 +11,7 @@
 #endif // QT_NO_QOBJECT
 #include <QDebug>
 #include <QtCore/private/qstdweb_p.h>
+#include <QtCore/private/qwasmglobal_p.h>
 
 #include <QFileInfo>
 #include <QDir>
@@ -109,7 +110,7 @@ void QWasmLocalStorageSettingsPrivate::remove(const QString &key)
 {
     const std::string removed = QString(m_keyPrefixes.first() + key).toStdString();
 
-    qstdweb::runTaskOnMainThread<void>([this, &removed, &key]() {
+    qwasmglobal::runTaskOnMainThread<void>([this, &removed, &key]() {
         std::vector<std::string> children = { removed };
         const int length = val::global("window")["localStorage"]["length"].as<int>();
         for (int i = 0; i < length; ++i) {
@@ -131,7 +132,7 @@ void QWasmLocalStorageSettingsPrivate::remove(const QString &key)
 
 void QWasmLocalStorageSettingsPrivate::set(const QString &key, const QVariant &value)
 {
-    qstdweb::runTaskOnMainThread<void>([this, &key, &value]() {
+    qwasmglobal::runTaskOnMainThread<void>([this, &key, &value]() {
         const std::string keyString = QString(m_keyPrefixes.first() + key).toStdString();
         const std::string valueString = QSettingsPrivate::variantToString(value).toStdString();
         val::global("window")["localStorage"].call<void>("setItem", keyString, valueString);
@@ -140,7 +141,7 @@ void QWasmLocalStorageSettingsPrivate::set(const QString &key, const QVariant &v
 
 std::optional<QVariant> QWasmLocalStorageSettingsPrivate::get(const QString &key) const
 {
-    return qstdweb::runTaskOnMainThread<std::optional<QVariant>>(
+    return qwasmglobal::runTaskOnMainThread<std::optional<QVariant>>(
             [this, &key]() -> std::optional<QVariant> {
                 for (const auto &prefix : m_keyPrefixes) {
                     const std::string keyString = QString(prefix + key).toStdString();
@@ -160,7 +161,7 @@ std::optional<QVariant> QWasmLocalStorageSettingsPrivate::get(const QString &key
 
 QStringList QWasmLocalStorageSettingsPrivate::children(const QString &prefix, ChildSpec spec) const
 {
-    return qstdweb::runTaskOnMainThread<QStringList>([this, &prefix, &spec]() -> QStringList {
+    return qwasmglobal::runTaskOnMainThread<QStringList>([this, &prefix, &spec]() -> QStringList {
         QSet<QString> nodes;
         // Loop through all keys on window.localStorage, return Qt keys belonging to
         // this application, with the correct prefix, and according to ChildSpec.
@@ -192,7 +193,7 @@ QStringList QWasmLocalStorageSettingsPrivate::children(const QString &prefix, Ch
 
 void QWasmLocalStorageSettingsPrivate::clear()
 {
-    qstdweb::runTaskOnMainThread<void>([this]() {
+    qwasmglobal::runTaskOnMainThread<void>([this]() {
         // Get all Qt keys from window.localStorage
         const int length = val::global("window")["localStorage"]["length"].as<int>();
         QStringList keys;
@@ -347,7 +348,7 @@ QSettingsPrivate *QSettingsPrivate::create(QSettings::Format format, QSettings::
 
     // Check if cookies are enabled (required for using persistent storage)
 
-    const bool cookiesEnabled = qstdweb::runTaskOnMainThread<bool>(
+    const bool cookiesEnabled = qwasmglobal::runTaskOnMainThread<bool>(
             []() { return val::global("navigator")["cookieEnabled"].as<bool>(); });
 
     constexpr QLatin1StringView cookiesWarningMessage(
diff --git a/src/corelib/platform/wasm/qstdweb.cpp b/src/corelib/platform/wasm/qstdweb.cpp
index c51c7e827c2..970e717212d 100644
--- a/src/corelib/platform/wasm/qstdweb.cpp
+++ b/src/corelib/platform/wasm/qstdweb.cpp
@@ -2,6 +2,8 @@
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #include "qstdweb_p.h"
+#include "qwasmsuspendresumecontrol_p.h"
+#include "qwasmglobal_p.h"
 
 #include <QtCore/qcoreapplication.h>
 #include <QtCore/qfile.h>
diff --git a/src/corelib/platform/wasm/qstdweb_p.h b/src/corelib/platform/wasm/qstdweb_p.h
index 5cb5db1f549..d34b86bce73 100644
--- a/src/corelib/platform/wasm/qstdweb_p.h
+++ b/src/corelib/platform/wasm/qstdweb_p.h
@@ -290,48 +290,6 @@ namespace qstdweb {
     bool Q_CORE_EXPORT haveAsyncify();
     bool Q_CORE_EXPORT haveJspi();
     bool canBlockCallingThread();
-
-    struct CancellationFlag
-    {
-    };
-
-#if QT_CONFIG(thread)
-    template<class T>
-    T proxyCall(std::function<T()> task, emscripten::ProxyingQueue *queue)
-    {
-        T result;
-        queue->proxySync(emscripten_main_runtime_thread_id(),
-                         [task, result = &result]() { *result = task(); });
-        return result;
-    }
-
-    template<>
-    inline void proxyCall<void>(std::function<void()> task, emscripten::ProxyingQueue *queue)
-    {
-        queue->proxySync(emscripten_main_runtime_thread_id(), task);
-    }
-
-    template<class T>
-    T runTaskOnMainThread(std::function<T()> task, emscripten::ProxyingQueue *queue)
-    {
-        return emscripten_is_main_runtime_thread() ? task() : proxyCall<T>(std::move(task), queue);
-    }
-
-    template<class T>
-    T runTaskOnMainThread(std::function<T()> task)
-    {
-        emscripten::ProxyingQueue singleUseQueue;
-        return runTaskOnMainThread<T>(task, &singleUseQueue);
-    }
-
-#else
-    template<class T>
-    T runTaskOnMainThread(std::function<T()> task)
-    {
-        return task();
-    }
-#endif // QT_CONFIG(thread)
-
 }
 
 QT_END_NAMESPACE
diff --git a/src/corelib/platform/wasm/qwasmglobal.cpp b/src/corelib/platform/wasm/qwasmglobal.cpp
new file mode 100644
index 00000000000..f80db160f08
--- /dev/null
+++ b/src/corelib/platform/wasm/qwasmglobal.cpp
@@ -0,0 +1,56 @@
+// Copyright (C) 2024 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#include "qwasmglobal_p.h"
+
+namespace qwasmglobal {
+
+Q_GLOBAL_STATIC(emscripten::ProxyingQueue, proxyingQueue);
+
+namespace {
+    void trampoline(void *context) {
+
+        auto async_fn = [](void *context){
+            std::function<void(void)> *fn = reinterpret_cast<std::function<void(void)> *>(context);
+            (*fn)();
+            delete fn;
+        };
+
+        emscripten_async_call(async_fn, context, 0);
+    }
+}
+
+void runOnMainThread(std::function<void(void)> fn)
+{
+#if QT_CONFIG(thread)
+    runTaskOnMainThread<void>(fn, proxyingQueue());
+#else
+    runTaskOnMainThread<void>(fn);
+#endif
+}
+
+// Runs a function asynchronously. Main thread only.
+void runAsync(std::function<void(void)> fn)
+{
+    Q_ASSERT(emscripten_is_main_runtime_thread());
+    trampoline(new std::function<void(void)>(fn));
+}
+
+// Runs a function on the main thread. The function always runs asynchronously,
+// also if the calling thread is the main thread.
+void runOnMainThreadAsync(std::function<void(void)> fn)
+{
+    void *context = new std::function<void(void)>(fn);
+#if QT_CONFIG(thread)
+    if (!emscripten_is_main_runtime_thread()) {
+        proxyingQueue()->proxyAsync(emscripten_main_runtime_thread_id(), [context]{
+            trampoline(context);
+        });
+        return;
+    }
+#endif
+    trampoline(context);
+}
+
+}
+
diff --git a/src/corelib/platform/wasm/qwasmglobal_p.h b/src/corelib/platform/wasm/qwasmglobal_p.h
new file mode 100644
index 00000000000..3d80014268d
--- /dev/null
+++ b/src/corelib/platform/wasm/qwasmglobal_p.h
@@ -0,0 +1,69 @@
+// Copyright (C) 2024 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
+
+#ifndef QWASMGLOBAL_P_H
+#define QWASMGLOBAL_P_H
+
+#include <emscripten/proxying.h>
+#include <emscripten/threading.h>
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+QT_BEGIN_NAMESPACE
+
+namespace qwasmglobal {
+
+#if QT_CONFIG(thread)
+    template<class T>
+    T proxyCall(std::function<T()> task, emscripten::ProxyingQueue *queue)
+    {
+        T result;
+        queue->proxySync(emscripten_main_runtime_thread_id(),
+                         [task, result = &result]() { *result = task(); });
+        return result;
+    }
+
+    template<>
+    inline void proxyCall<void>(std::function<void()> task, emscripten::ProxyingQueue *queue)
+    {
+        queue->proxySync(emscripten_main_runtime_thread_id(), task);
+    }
+
+    template<class T>
+    T runTaskOnMainThread(std::function<T()> task, emscripten::ProxyingQueue *queue)
+    {
+        return emscripten_is_main_runtime_thread() ? task() : proxyCall<T>(std::move(task), queue);
+    }
+
+    template<class T>
+    T runTaskOnMainThread(std::function<T()> task)
+    {
+        emscripten::ProxyingQueue singleUseQueue;
+        return runTaskOnMainThread<T>(task, &singleUseQueue);
+    }
+
+#else
+    template<class T>
+    T runTaskOnMainThread(std::function<T()> task)
+    {
+        return task();
+    }
+#endif // QT_CONFIG(thread)
+
+    void runAsync(std::function<void(void)> fn);
+    void runOnMainThread(std::function<void(void)> fn);
+    void runOnMainThreadAsync(std::function<void(void)> fn);
+}
+
+QT_END_NAMESPACE
+
+#endif // QWASMGLOBAL_P_H
diff --git a/src/corelib/platform/wasm/qwasmsocket.cpp b/src/corelib/platform/wasm/qwasmsocket.cpp
index e7901a54fb9..64af09e9871 100644
--- a/src/corelib/platform/wasm/qwasmsocket.cpp
+++ b/src/corelib/platform/wasm/qwasmsocket.cpp
@@ -2,6 +2,7 @@
 // SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
 #include "qwasmsocket_p.h"
+#include "qwasmglobal_p.h"
 #include <QtCore/qsocketnotifier.h>
 
 #include "emscripten.h"
@@ -28,7 +29,7 @@ void QWasmSocket::registerSocketNotifier(QSocketNotifier *notifier)
     bool wasEmpty = g_socketNotifiers.empty();
     g_socketNotifiers.insert({notifier->socket(), notifier});
     if (wasEmpty)
-        QEventDispatcherWasm::runOnMainThread([] { setEmscriptenSocketCallbacks(); });
+        qwasmglobal::runOnMainThread([] { setEmscriptenSocketCallbacks(); });
 
     int count;
     ioctl(notifier->socket(), FIONREAD, &count);
@@ -52,7 +53,7 @@ void QWasmSocket::unregisterSocketNotifier(QSocketNotifier *notifier)
     }
 
     if (g_socketNotifiers.empty())
-        QEventDispatcherWasm::runOnMainThread([] { clearEmscriptenSocketCallbacks(); });
+        qwasmglobal::runOnMainThread([] { clearEmscriptenSocketCallbacks(); });
 }
 
 void QWasmSocket::clearSocketNotifiers()
@@ -104,7 +105,7 @@ void QWasmSocket::socketError(int socket, int err, const char* msg, void *contex
     // the Qt handler.
     // It is currently unclear if this problem is caused by code in Qt or in Emscripten, or
     // if this completely fixes the problem.
-    QEventDispatcherWasm::runAsync([socket](){
+    qwasmglobal::runAsync([socket](){
         auto notifiersRange = g_socketNotifiers.equal_range(socket);
         std::vector<std::pair<int, QSocketNotifier *>> notifiers(notifiersRange.first, notifiersRange.second);
         for (auto [_, notifier]: notifiers) {
@@ -118,7 +119,7 @@ void QWasmSocket::socketOpen(int socket, void *context)
 {
     Q_UNUSED(context);
 
-    QEventDispatcherWasm::runAsync([socket](){
+    qwasmglobal::runAsync([socket](){
         auto notifiersRange = g_socketNotifiers.equal_range(socket);
         std::vector<std::pair<int, QSocketNotifier *>> notifiers(notifiersRange.first, notifiersRange.second);
         for (auto [_, notifier]: notifiers) {
@@ -146,7 +147,7 @@ void QWasmSocket::socketMessage(int socket, void *context)
 {
     Q_UNUSED(context);
 
-    QEventDispatcherWasm::runAsync([socket](){
+    qwasmglobal::runAsync([socket](){
         auto notifiersRange = g_socketNotifiers.equal_range(socket);
         std::vector<std::pair<int, QSocketNotifier *>> notifiers(notifiersRange.first, notifiersRange.second);
         for (auto [_, notifier]: notifiers) {
@@ -167,7 +168,7 @@ void QWasmSocket::socketClose(int socket, void *context)
     if (socket == 0)
         return;
 
-    QEventDispatcherWasm::runAsync([socket](){
+    qwasmglobal::runAsync([socket](){
         auto notifiersRange = g_socketNotifiers.equal_range(socket);
         std::vector<std::pair<int, QSocketNotifier *>> notifiers(notifiersRange.first, notifiersRange.second);
         for (auto [_, notifier]: notifiers)
diff --git a/src/network/access/qnetworkreplywasmimpl.cpp b/src/network/access/qnetworkreplywasmimpl.cpp
index 7d225c7e862..1bcf32e643a 100644
--- a/src/network/access/qnetworkreplywasmimpl.cpp
+++ b/src/network/access/qnetworkreplywasmimpl.cpp
@@ -9,7 +9,7 @@
 #include <QtCore/qcoreapplication.h>
 #include <QtCore/qfileinfo.h>
 #include <QtCore/qthread.h>
-#include <QtCore/private/qeventdispatcher_wasm_p.h>
+#include <QtCore/private/qwasmglobal_p.h>
 #include <QtCore/private/qoffsetstringarray_p.h>
 #include <QtCore/private/qtools_p.h>
 
@@ -281,7 +281,7 @@ void QNetworkReplyWasmImplPrivate::doSendRequest()
         }
     }
 
-    QEventDispatcherWasm::runOnMainThread([attr, fetchContext = m_fetchContext]() mutable {
+    qwasmglobal::runOnMainThread([attr, fetchContext = m_fetchContext]() mutable {
         std::unique_lock lock{ fetchContext->mutex };
         if (fetchContext->state == FetchContext::State::CANCELED) {
             fetchContext->state = FetchContext::State::FINISHED;