From f01103ec221c5a261aa96669aa1d32245d78e232 Mon Sep 17 00:00:00 2001
From: Richard Heck <rgheck@comcast.net>
Date: Thu, 17 Nov 2011 18:06:06 +0000
Subject: [PATCH] Backport fix for crash reported by Pavel.

git-svn-id: svn://svn.lyx.org/lyx/lyx-devel/branches/BRANCH_2_0_X@40206 a592a061-630c-0410-9148-cb99ea01b6c8
---
 src/Buffer.cpp | 87 +++++++++++++++++++++++++++++++++-----------------
 1 file changed, 58 insertions(+), 29 deletions(-)

diff --git a/src/Buffer.cpp b/src/Buffer.cpp
index 4b86241ab5..d01ff7bce8 100644
--- a/src/Buffer.cpp
+++ b/src/Buffer.cpp
@@ -140,6 +140,10 @@ void showPrintError(string const & name)
 	Alert::error(_("Print document failed"), str);
 }
 
+/// a list of Buffers we cloned
+set<Buffer *> cloned_buffer_list;
+
+
 } // namespace anon
 
 
@@ -386,36 +390,50 @@ Buffer::~Buffer()
 		return;
 	}
 
-	// loop over children
-	Impl::BufferPositionMap::iterator it = d->children_positions.begin();
-	Impl::BufferPositionMap::iterator end = d->children_positions.end();
-	for (; it != end; ++it) {
-		Buffer * child = const_cast<Buffer *>(it->first);
-		if (d->cloned_buffer_)
-			delete child;
-		// The child buffer might have been closed already.
-		else if (theBufferList().isLoaded(child))
-			theBufferList().releaseChild(this, child);
-	}
+	if (isClone()) {
+		// this is in case of recursive includes: we won't try to delete
+		// ourselves as a child.
+		cloned_buffer_list.erase(this);
+		// loop over children
+		Impl::BufferPositionMap::iterator it = d->children_positions.begin();
+		Impl::BufferPositionMap::iterator end = d->children_positions.end();
+		for (; it != end; ++it) {
+			Buffer * child = const_cast<Buffer *>(it->first);
+				if (cloned_buffer_list.erase(child))
+					delete child;
+		}
+		// FIXME Do we really need to do this right before we delete d?
+		// clear references to children in macro tables
+		d->children_positions.clear();
+		d->position_to_children.clear();
+	} else {
+		// loop over children
+		Impl::BufferPositionMap::iterator it = d->children_positions.begin();
+		Impl::BufferPositionMap::iterator end = d->children_positions.end();
+		for (; it != end; ++it) {
+			Buffer * child = const_cast<Buffer *>(it->first);
+			if (theBufferList().isLoaded(child))
+				theBufferList().releaseChild(this, child);
+		}
 
-	if (!isClean()) {
-		docstring msg = _("LyX attempted to close a document that had unsaved changes!\n");
-		msg += emergencyWrite();
-		Alert::warning(_("Attempting to close changed document!"), msg);
-	}
-		
-	// clear references to children in macro tables
-	d->children_positions.clear();
-	d->position_to_children.clear();
+		if (!isClean()) {
+			docstring msg = _("LyX attempted to close a document that had unsaved changes!\n");
+			msg += emergencyWrite();
+			Alert::warning(_("Attempting to close changed document!"), msg);
+		}
 
-	if (!d->cloned_buffer_ && !d->temppath.destroyDirectory()) {
-		Alert::warning(_("Could not remove temporary directory"),
-			bformat(_("Could not remove the temporary directory %1$s"),
-			from_utf8(d->temppath.absFileName())));
-	}
+		// FIXME Do we really need to do this right before we delete d?
+		// clear references to children in macro tables
+		d->children_positions.clear();
+		d->position_to_children.clear();
 
-	if (!isClone())
+		if (!d->temppath.destroyDirectory()) {
+			Alert::warning(_("Could not remove temporary directory"),
+				bformat(_("Could not remove the temporary directory %1$s"),
+				from_utf8(d->temppath.absFileName())));
+		}
 		removePreviews();
+	}
 
 	delete d;
 }
@@ -425,9 +443,20 @@ Buffer * Buffer::clone() const
 {
 	BufferMap bufmap;
 	masterBuffer()->clone(bufmap);
-	BufferMap::iterator it = bufmap.find(this);
-	LASSERT(it != bufmap.end(), return 0);
-	return it->second;
+
+	// make sure we got cloned
+	BufferMap::const_iterator bit = bufmap.find(this);
+	LASSERT(bit != bufmap.end(), return 0);
+	Buffer * cloned_buffer = bit->second;
+
+	// record the list of cloned buffers
+	cloned_buffer_list.clear();
+	BufferMap::iterator it = bufmap.begin();
+	BufferMap::iterator en = bufmap.end();
+	for (; it != en; ++it)
+		cloned_buffer_list.insert(it->second);
+
+	return cloned_buffer;
 }