From 8e8c451ca1ddfa660e297b5c562a6a1ed61b717a Mon Sep 17 00:00:00 2001
From: Enrico Forestieri <forenr@lyx.org>
Date: Wed, 5 Jan 2011 14:02:35 +0000
Subject: [PATCH] Fix bug #6538 (Figure: relative path changed to absolute on
 copy/paste)

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/branches/BRANCH_1_6_X@37114 a592a061-630c-0410-9148-cb99ea01b6c8
---
 src/frontends/qt4/GuiClipboard.cpp | 38 +++++++++++++++++++++++++-----
 src/frontends/qt4/GuiClipboard.h   |  4 ++++
 src/insets/InsetTabular.cpp        |  3 +--
 status.16x                         |  3 +++
 4 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/src/frontends/qt4/GuiClipboard.cpp b/src/frontends/qt4/GuiClipboard.cpp
index 03fb6312aa..01a191c5b5 100644
--- a/src/frontends/qt4/GuiClipboard.cpp
+++ b/src/frontends/qt4/GuiClipboard.cpp
@@ -44,6 +44,8 @@
 #include <QString>
 #include <QStringList>
 
+#include <boost/crc.hpp>
+
 #include <memory>
 #include <map>
 
@@ -325,6 +327,13 @@ void GuiClipboard::put(string const & lyx, docstring const & text)
 	if (!lyx.empty()) {
 		QByteArray const qlyx(lyx.c_str(), lyx.size());
 		data->setData(lyxMimeType(), qlyx);
+		// If the OS has not the concept of clipboard ownership,
+		// we recognize internal data through its checksum.
+		if (!hasInternal()) {
+			boost::crc_32_type crc32;
+			crc32.process_bytes(lyx.c_str(), lyx.size());
+			checksum = crc32.checksum();
+		}
 	}
 	// Don't test for text.empty() since we want to be able to clear the
 	// clipboard.
@@ -397,11 +406,26 @@ bool GuiClipboard::hasGraphicsContents(Clipboard::GraphicsType type) const
 
 bool GuiClipboard::isInternal() const
 {
+	if (!hasLyXContents())
+		return false;
+
 	// ownsClipboard() is also true for stuff coming from dialogs, e.g.
-	// the preamble dialog
-	// FIXME: This does only work on X11, since ownsClipboard() is
-	// hardwired to return false on Windows and OS X.
-	return qApp->clipboard()->ownsClipboard() && hasLyXContents();
+	// the preamble dialog. This does only work on X11 and Windows, since
+	// ownsClipboard() is hardwired to return false on OS X.
+	if (hasInternal())
+		return qApp->clipboard()->ownsClipboard();
+
+	// We are running on OS X: Check whether clipboard data is from
+	// ourself by comparing its checksum with the stored one.
+	QMimeData const * source =
+		qApp->clipboard()->mimeData(QClipboard::Clipboard);
+	if (!source)
+		return false;
+	QByteArray const ar = source->data(lyxMimeType());
+	string const data(ar.data(), ar.count());
+	boost::crc_32_type crc32;
+	crc32.process_bytes(data.c_str(), data.size());
+	return checksum == crc32.checksum();
 }
 
 
@@ -409,8 +433,10 @@ bool GuiClipboard::hasInternal() const
 {
 	// Windows and Mac OS X does not have the concept of ownership;
 	// the clipboard is a fully global resource so all applications 
-	// are notified of changes.
-#if (defined(Q_WS_X11))
+	// are notified of changes. However, on Windows ownership is
+	// emulated by Qt through the OleIsCurrentClipboard() API, while
+	// on Mac OS X we deal with this issue by ourself.
+#if (defined(Q_WS_X11) || defined(Q_WS_WIN))
 	return true;
 #else
 	return false;
diff --git a/src/frontends/qt4/GuiClipboard.h b/src/frontends/qt4/GuiClipboard.h
index d0552a8281..5f8f32ca73 100644
--- a/src/frontends/qt4/GuiClipboard.h
+++ b/src/frontends/qt4/GuiClipboard.h
@@ -18,6 +18,8 @@
 
 #include <QObject>
 
+#include <boost/cstdint.hpp>
+
 namespace lyx {
 namespace frontend {
 
@@ -57,6 +59,8 @@ private:
 	bool text_clipboard_empty_;
 	bool has_lyx_contents_;
 	bool has_graphics_contents_;
+	/// checksum for internal clipboard data (used on Mac) 
+	boost::uint32_t checksum;
 };
 
 QString const lyxMimeType();
diff --git a/src/insets/InsetTabular.cpp b/src/insets/InsetTabular.cpp
index 104d9b4350..d176d474d0 100644
--- a/src/insets/InsetTabular.cpp
+++ b/src/insets/InsetTabular.cpp
@@ -3729,8 +3729,7 @@ void InsetTabular::doDispatch(Cursor & cur, FuncRequest & cmd)
 				cell(cur.idx())->dispatch(cur, cmd);
 			break;
 		}
-		if (theClipboard().isInternal() ||
-		    !theClipboard().hasInternal() && theClipboard().hasLyXContents()) {
+		if (theClipboard().isInternal()) {
 			cur.recordUndoInset(INSERT_UNDO);
 			pasteClipboard(cur);
 		}
diff --git a/status.16x b/status.16x
index ba8b038161..18d86c3f5d 100644
--- a/status.16x
+++ b/status.16x
@@ -117,6 +117,9 @@ What's new
 - Don't allow to make tables within floats "long" as this could lead to
   LaTeX errors (bug 6585).
 
+- Don't use absolute paths on internal copy/paste operations on Mac
+  (bug 6538).
+
 - Correct the denomination of the languages Norsk and Nynorsk.
 
 - Do not allow to put the cursor in an InsetInfo. Instead, a context