1 files changed, 148 insertions, 0 deletions
diff --git a/src/corelib/ipc/qsharedmemory_win.cpp b/src/corelib/ipc/qsharedmemory_win.cpp
new file mode 100644
index 0000000000..472f34f9a1
--- /dev/null
+++ b/src/corelib/ipc/qsharedmemory_win.cpp
@@ -0,0 +1,148 @@
+// Copyright (C) 2016 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 "qsharedmemory.h"
+#include "qsharedmemory_p.h"
+#include "qsystemsemaphore.h"
+#include <qdebug.h>
+#include <qt_windows.h>
+
+QT_BEGIN_NAMESPACE
+
+using namespace Qt::StringLiterals;
+
+#if QT_CONFIG(sharedmemory)
+
+void QSharedMemoryPrivate::setWindowsErrorString(QLatin1StringView function)
+{
+    DWORD windowsError = GetLastError();
+    if (windowsError == 0)
+        return;
+    switch (windowsError) {
+    case ERROR_ALREADY_EXISTS:
+        error = QSharedMemory::AlreadyExists;
+        errorString = QSharedMemory::tr("%1: already exists").arg(function);
+    break;
+    case ERROR_FILE_NOT_FOUND:
+        error = QSharedMemory::NotFound;
+        errorString = QSharedMemory::tr("%1: doesn't exist").arg(function);
+        break;
+    case ERROR_COMMITMENT_LIMIT:
+        error = QSharedMemory::InvalidSize;
+        errorString = QSharedMemory::tr("%1: invalid size").arg(function);
+        break;
+    case ERROR_NO_SYSTEM_RESOURCES:
+    case ERROR_NOT_ENOUGH_MEMORY:
+        error = QSharedMemory::OutOfResources;
+        errorString = QSharedMemory::tr("%1: out of resources").arg(function);
+        break;
+    case ERROR_ACCESS_DENIED:
+        error = QSharedMemory::PermissionDenied;
+        errorString = QSharedMemory::tr("%1: permission denied").arg(function);
+        break;
+    default:
+        errorString = QSharedMemory::tr("%1: unknown error: %2")
+                .arg(function, qt_error_string(windowsError));
+        error = QSharedMemory::UnknownError;
+#if defined QSHAREDMEMORY_DEBUG
+        qDebug() << errorString << "key" << key;
+#endif
+    }
+}
+
+HANDLE QSharedMemoryWin32::handle(QSharedMemoryPrivate *self)
+{
+    if (!hand) {
+        const auto function = "QSharedMemory::handle"_L1;
+        if (self->nativeKey.isEmpty()) {
+            self->setError(QSharedMemory::KeyError,
+                           QSharedMemory::tr("%1: unable to make key").arg(function));
+            return 0;
+        }
+        hand = OpenFileMapping(FILE_MAP_ALL_ACCESS, false,
+                               reinterpret_cast<const wchar_t *>(self->nativeKey.nativeKey().utf16()));
+        if (!hand) {
+            self->setWindowsErrorString(function);
+            return 0;
+        }
+    }
+    return hand;
+}
+
+bool QSharedMemoryWin32::cleanHandle(QSharedMemoryPrivate *)
+{
+    if (hand != 0 && !CloseHandle(hand)) {
+        hand = 0;
+        return false;
+    }
+    hand = 0;
+    return true;
+}
+
+bool QSharedMemoryWin32::create(QSharedMemoryPrivate *self, qsizetype size)
+{
+    const auto function = "QSharedMemory::create"_L1;
+    if (self->nativeKey.isEmpty()) {
+        self->setError(QSharedMemory::KeyError,
+                       QSharedMemory::tr("%1: key error").arg(function));
+        return false;
+    }
+
+    // Create the file mapping.
+    DWORD high, low;
+    if constexpr (sizeof(qsizetype) == 8)
+        high = DWORD(quint64(size) >> 32);
+    else
+        high = 0;
+    low = DWORD(size_t(size) & 0xffffffff);
+    hand = CreateFileMapping(INVALID_HANDLE_VALUE, 0, PAGE_READWRITE, high, low,
+                             reinterpret_cast<const wchar_t *>(self->nativeKey.nativeKey().utf16()));
+    self->setWindowsErrorString(function);
+
+    // hand is valid when it already exists unlike unix so explicitly check
+    return self->error != QSharedMemory::AlreadyExists && hand;
+}
+
+bool QSharedMemoryWin32::attach(QSharedMemoryPrivate *self, QSharedMemory::AccessMode mode)
+{
+    // Grab a pointer to the memory block
+    int permissions = (mode == QSharedMemory::ReadOnly ? FILE_MAP_READ : FILE_MAP_ALL_ACCESS);
+    self->memory = (void *)MapViewOfFile(handle(self), permissions, 0, 0, 0);
+    if (!self->memory) {
+        self->setWindowsErrorString("QSharedMemory::attach"_L1);
+        cleanHandle(self);
+        return false;
+    }
+
+    // Grab the size of the memory we have been given (a multiple of 4K on windows)
+    MEMORY_BASIC_INFORMATION info;
+    if (!VirtualQuery(self->memory, &info, sizeof(info))) {
+        // Windows doesn't set an error code on this one,
+        // it should only be a kernel memory error.
+        self->setError(QSharedMemory::UnknownError,
+                       QSharedMemory::tr("%1: size query failed")
+                       .arg("QSharedMemory::attach: "_L1));
+        return false;
+    }
+    self->size = qsizetype(info.RegionSize);
+
+    return true;
+}
+
+bool QSharedMemoryWin32::detach(QSharedMemoryPrivate *self)
+{
+    // umap memory
+    if (!UnmapViewOfFile(self->memory)) {
+        self->setWindowsErrorString("QSharedMemory::detach"_L1);
+        return false;
+    }
+    self->memory = 0;
+    self->size = 0;
+
+    // close handle
+    return cleanHandle(self);
+}
+
+#endif // QT_CONFIG(sharedmemory)
+
+QT_END_NAMESPACE