Don't require stream data provider to know length in advance

Breaking API change: length parameter has disappeared from the
StreamDataProvider version of QPDFObjectHandle::replaceStreamData
since it is no longer necessary to compute it in advance.  This
breaking change is justified by the fact that removing the length
parameter provides the caller an opportunity to simplify the calling
code.

1 files changed, 18 insertions, 0 deletions

diff --git a/ChangeLog b/ChangeLog
index 5e3092de..6fa4c45d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,21 @@
+2012-07-07  Jay Berkenbilt  <ejb@ql.org>
+
+	* NOTE: BREAKING API CHANGE.  Remove previously required length
+	parameter from the version QPDFObjectHandle::replaceStreamData
+	that uses a stream data provider.  Prior to qpdf 3.0.0, you had to
+	compute the stream length in advance so that qpdf could internally
+	verify that the stream data had the same length every time the
+	provider was invoked.  Now this requirement is enforced a
+	different way, and the length parameter is no longer required.
+	Note that I take API-breaking changes very seriously and only did
+	it in this case since the lack of need to know length in advance
+	could significantly simplify people's code.  If you were
+	previously going to a lot of trouble to compute the length of the
+	new stream data in advance, you now no longer have to do that.
+	You can just drop the length parameter and remove any code that
+	was previously computing the length.  Thanks to Tobias Hoffmann
+	for pointing out how annoying the original interface was.
+
 2012-07-05  Jay Berkenbilt  <ejb@ql.org>
 
 	* Add QPDFWriter methods to write to an already open stdio FILE*.