tdf#116420: Windows: Test if a filepath redirects to a WebDAV resource

In Windows, filesystem redirectors can map WebDAV resources to UNC
paths, or to drive-based "local" paths; so a WebDAV URI of the form
"http://WebDADServer/root/directory/File.ext" may be accessed using
"\\WebDADServer\root\directory\File.ext" or "Z:\directory\File.ext".

When using these paths, failure to create a lockfile aside the opened
document should not be considered an error; so this patch checks for
this.

Regression from commit 6ca3b3648e25ae9d4d2d29a0df83349198ec3f5e.

Change-Id: I1de55b66447dc91d22b6d2b5b121de96bf32e4ee
Reviewed-on: https://gerrit.libreoffice.org/53070
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

2 files changed, 79 insertions, 0 deletions

diff --git a/tools/Library_tl.mk b/tools/Library_tl.mk
index 69b3149251e4..2aee438fb2e9 100644
--- a/tools/Library_tl.mk
+++ b/tools/Library_tl.mk
@@ -47,6 +47,7 @@ $(eval $(call gb_Library_add_exception_objects,tl,\
     tools/source/datetime/tdate \
     tools/source/datetime/ttime \
     tools/source/debug/debug \
+    tools/source/fsys/fileutil \
     tools/source/fsys/urlobj \
     tools/source/fsys/wldcrd \
     tools/source/generic/b3dtrans \
diff --git a/tools/source/fsys/fileutil.cxx b/tools/source/fsys/fileutil.cxx
new file mode 100644
index 000000000000..a24f82316813
--- /dev/null
+++ b/tools/source/fsys/fileutil.cxx
@@ -0,0 +1,78 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * 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/.
+ */
+
+#include <tools/fileutil.hxx>
+#include <tools/urlobj.hxx>
+#if defined _WIN32
+#include <osl/file.hxx>
+#include <string.h>
+#include <o3tl/char16_t2wchar_t.hxx>
+#include <o3tl/make_unique.hxx>
+#define WIN32_LEAN_AND_MEAN
+#include <Windows.h>
+#endif
+
+namespace tools
+{
+bool IsMappedWebDAVPath(const INetURLObject& aURL)
+{
+#if defined _WIN32
+    if (aURL.GetProtocol() == INetProtocol::File)
+    {
+        OUString sURL = aURL.GetMainURL(INetURLObject::DecodeMechanism::NONE);
+        OUString aSystemPath;
+        if (osl::FileBase::getSystemPathFromFileURL(sURL, aSystemPath) == osl::FileBase::E_None)
+        {
+            DWORD nSize = MAX_PATH;
+            auto bufUNC(o3tl::make_unique<char[]>(nSize));
+            DWORD nResult = WNetGetUniversalNameW(o3tl::toW(aSystemPath.getStr()),
+                                                  UNIVERSAL_NAME_INFO_LEVEL, bufUNC.get(), &nSize);
+            if (nResult == ERROR_MORE_DATA)
+            {
+                bufUNC = o3tl::make_unique<char[]>(nSize);
+                nResult = WNetGetUniversalNameW(o3tl::toW(aSystemPath.getStr()),
+                                                UNIVERSAL_NAME_INFO_LEVEL, bufUNC.get(), &nSize);
+            }
+            if (nResult == NO_ERROR || nResult == ERROR_BAD_DEVICE)
+            {
+                NETRESOURCEW aReq{};
+                if (nResult == ERROR_BAD_DEVICE) // The path could already be an UNC
+                    aReq.lpRemoteName = const_cast<LPWSTR>(o3tl::toW(aSystemPath.getStr()));
+                else
+                {
+                    auto pInfo = reinterpret_cast<LPUNIVERSAL_NAME_INFOW>(bufUNC.get());
+                    aReq.lpRemoteName = pInfo->lpUniversalName;
+                }
+                nSize = 1024;
+                auto bufInfo(o3tl::make_unique<char[]>(nSize));
+                LPWSTR pSystem = nullptr;
+                nResult = WNetGetResourceInformationW(&aReq, bufInfo.get(), &nSize, &pSystem);
+                if (nResult == ERROR_MORE_DATA)
+                {
+                    bufInfo = o3tl::make_unique<char[]>(nSize);
+                    nResult = WNetGetResourceInformationW(&aReq, bufInfo.get(), &nSize, &pSystem);
+                }
+                if (nResult == NO_ERROR)
+                {
+                    LPNETRESOURCEW pInfo = reinterpret_cast<LPNETRESOURCEW>(bufInfo.get());
+                    if (wcscmp(pInfo->lpProvider, L"Web Client Network") == 0)
+                        return true;
+                }
+            }
+        }
+    }
+#else
+    (void)aURL;
+#endif
+    return false;
+}
+
+} // namespace tools
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */