[client] windows: implement file clipboard support

client/include/core/clipboard.h

@@ -61,7 +61,7 @@ bool clipboard_requestCancel(LG_ClipboardRequest request,
 bool clipboard_request(LG_ClipboardData type,
     LG_ClipboardReplyFn replyFn, void * opaque);
 
-/* File-dataset transport entry points used by clipboard_files.c. */
+/* File-dataset transport entry points used by platform clipboard backends. */
 bool clipboard_fileAcquire(uint64_t dataset, uint64_t acquisition);
 bool clipboard_fileAcquired(uint64_t dataset, uint64_t acquisition,
     LG_ClipboardFileError error);

client/include/core/clipboard_files.h

@@ -23,6 +23,10 @@
 
 #include "interface/clipboard.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 bool clipboardFiles_init(void);
 void clipboardFiles_free(void);
 
@@ -83,4 +87,8 @@ bool clipboardFiles_testLocalRequest(
     const LG_ClipboardFileRequest * request);
 #endif
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif

client/include/platform/windows/clipboard_files.h

@@ -0,0 +1,43 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _H_LG_PLATFORM_WINDOWS_CLIPBOARD_FILES_
+#define _H_LG_PLATFORM_WINDOWS_CLIPBOARD_FILES_
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <windows.h>
+#include <ole2.h>
+#include <shellapi.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+bool windowsClipboardFiles_setLocalDrop(HDROP drop);
+bool windowsClipboardFiles_createRemoteDataObject(uint64_t presentation,
+    IDataObject ** dataObject);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

client/include/platform/windows/clipboard_files_win32.h

@@ -0,0 +1,88 @@
+/**
+ * Looking Glass
+ * Copyright © 2017-2026 The Looking Glass Authors
+ * https://looking-glass.io
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef _H_LG_PLATFORM_WINDOWS_CLIPBOARD_FILES_WIN32_
+#define _H_LG_PLATFORM_WINDOWS_CLIPBOARD_FILES_WIN32_
+
+#include "interface/clipboard.h"
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#include <windows.h>
+#include <ole2.h>
+#include <shellapi.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct WindowsClipboardLocalFiles     WindowsClipboardLocalFiles;
+typedef struct WindowsClipboardRemoteManifest WindowsClipboardRemoteManifest;
+
+typedef struct WindowsClipboardRemoteProviderOps
+{
+  HRESULT (*read   )(void * opaque, uint64_t dataset, uint64_t acquisition,
+      uint64_t node, uint64_t offset, void * data, ULONG length,
+      ULONG * read);
+  void    (*release)(void * opaque, uint64_t dataset, uint64_t acquisition);
+}
+WindowsClipboardRemoteProviderOps;
+
+/* Capture copies the selection metadata. List and read return malloc-owned
+ * buffers which the caller releases with free(). */
+WindowsClipboardLocalFiles * windowsClipboardLocalFilesCapture(HDROP drop,
+    LG_ClipboardFileError * error);
+void windowsClipboardLocalFilesRetain(WindowsClipboardLocalFiles * files);
+void windowsClipboardLocalFilesRelease(WindowsClipboardLocalFiles * files);
+bool windowsClipboardLocalFilesList(WindowsClipboardLocalFiles * files,
+    uint64_t node, void ** data, size_t * size,
+    LG_ClipboardFileError * error);
+bool windowsClipboardLocalFilesRead(WindowsClipboardLocalFiles * files,
+    uint64_t node, uint64_t offset, uint32_t length, void ** data,
+    size_t * size, LG_ClipboardFileError * error);
+
+WindowsClipboardRemoteManifest * windowsClipboardRemoteManifestCreate(void);
+void windowsClipboardRemoteManifestFree(
+    WindowsClipboardRemoteManifest * manifest);
+/* Call NextDirectory before each LIST request, then append the complete
+ * response for the returned node. The first returned node is the wire root. */
+bool windowsClipboardRemoteManifestAppendList(
+    WindowsClipboardRemoteManifest * manifest, uint64_t parent,
+    const void * data, size_t size, LG_ClipboardFileError * error);
+bool windowsClipboardRemoteManifestNextDirectory(
+    WindowsClipboardRemoteManifest * manifest, uint64_t * node);
+bool windowsClipboardRemoteManifestHasEntries(
+    const WindowsClipboardRemoteManifest * manifest);
+
+/* The data object owns one provider lease after a successful return. The
+ * release callback runs once after both the object and all of its streams are
+ * released. A failed call does not invoke it. */
+HRESULT windowsClipboardRemoteCreateDataObject(
+    WindowsClipboardRemoteManifest * manifest, uint64_t dataset,
+    uint64_t acquisition, const WindowsClipboardRemoteProviderOps * ops,
+    void * opaque, IDataObject ** object);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif