liblibo: expose a C API for ABI reasons, and wrap with C++.

Change-Id: I7b3bcead05788e663d94724522bfa3f227b15499

2 files changed, 84 insertions, 8 deletions

diff --git a/desktop/inc/liblibreoffice.h b/desktop/inc/liblibreoffice.h
new file mode 100644
index 000000000000..db3b8358a9af
--- /dev/null
+++ b/desktop/inc/liblibreoffice.h
@@ -0,0 +1,46 @@
+/* -*- 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/.
+ */
+
+#ifndef INCLUDED_DESKTOP_INC_LIBLIBREOFFICE_H
+#define INCLUDED_DESKTOP_INC_LIBLIBREOFFICE_H
+
+#ifdef __cplusplus
+  extern "C" {
+#endif
+
+typedef struct _LibreOffice LibreOffice;
+typedef struct _LibreOfficeDocument LibreOfficeDocument;
+
+struct _LibreOffice {
+  int  nSize;
+
+  void                 (*destroy)       (LibreOffice *pThis);
+  int                  (*initialize)    (LibreOffice *pThis,
+                                         const char *pInstallPath);
+  LibreOfficeDocument *(*documentLoad)  (LibreOffice *pThis,
+                                         const char *pURL);
+  char *               (*getError)      (LibreOffice *pThis);
+};
+
+struct _LibreOfficeDocument {
+  int  nSize;
+
+  void (*destroy)   (LibreOfficeDocument *pThis);
+  int (*saveAs)     (LibreOfficeDocument *pThis,
+                     const char *pUrl, const char *pFormat);
+};
+
+LibreOffice *lo_init (const char *install_path);
+
+#ifdef __cplusplus
+  }
+#endif
+
+#endif
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/desktop/inc/liblibreoffice.hxx b/desktop/inc/liblibreoffice.hxx
index 28c23476c899..81207ac4eedc 100644
--- a/desktop/inc/liblibreoffice.hxx
+++ b/desktop/inc/liblibreoffice.hxx
@@ -10,30 +10,60 @@
 #ifndef INCLUDED_DESKTOP_INC_LIBLIBREOFFICE_HXX
 #define INCLUDED_DESKTOP_INC_LIBLIBREOFFICE_HXX
 
+#include <liblibreoffice.h>
+
+/*
+ * The reasons this C++ code is not as pretty as it could be are:
+ *  a) provide a pure C API - that's useful for some people
+ *  b) allow ABI stability - C++ vtables are not good for that.
+ *  c) avoid C++ types as part of the API.
+ */
+
 class LODocument
 {
+    LibreOfficeDocument *mpDoc;
 public:
-    virtual ~LODocument() {}
+    inline LODocument( LibreOfficeDocument *pDoc ) : mpDoc( pDoc ) {}
+    inline ~LODocument() { mpDoc->destroy( mpDoc ); }
 
     // Save as the given format, if format is NULL sniff from ext'n
-    virtual bool saveAs (const char *url, const char *format = NULL) = 0;
+    inline bool saveAs( const char *url, const char *format = NULL )
+    {
+        return mpDoc->saveAs( mpDoc, url, format );
+    }
 };
 
 class LibLibreOffice
 {
+    LibreOffice *mpThis;
 public:
-    virtual ~LibLibreOffice () {};
+    inline LibLibreOffice( LibreOffice *pThis ) : mpThis( pThis ) {}
+    inline ~LibLibreOffice() { mpThis->destroy( mpThis ); };
 
-    virtual bool        initialize (const char *installPath) = 0;
+    inline bool initialize( const char *installPath )
+    {
+        return mpThis->initialize( mpThis, installPath );
+    }
 
-    virtual LODocument *documentLoad (const char *url) = 0;
+    inline LODocument *documentLoad( const char *url )
+    {
+        LibreOfficeDocument *pDoc = mpThis->documentLoad( mpThis, url );
+        if( !pDoc )
+            return NULL;
+        return new LODocument( pDoc );
+    }
 
     // return the last error as a string, free me.
-    virtual char       *getError() = 0;
-
+    inline char *getError() { return mpThis->getError( mpThis ); }
 };
 
-LibLibreOffice *lo_init (const char *install_path);
+inline LibLibreOffice *lo_cpp_init( const char *install_path )
+{
+    LibreOffice *pThis = lo_init( install_path );
+    if( !pThis || !pThis->nSize > 0 )
+        return NULL;
+    return new LibLibreOffice( pThis );
+}
 
 #endif
 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */