allow 0-size message

It likely means the input is broken, but there is no need to reject it.
Let's just produce a dummy, empty message.

Change-Id: I03a1e9827f21f6a0ce69d7e16dfcf2e9a0f2d44f

1 files changed, 2 insertions, 1 deletions

diff --git a/src/lib/IWAMessage.cpp b/src/lib/IWAMessage.cpp
index c01b1b6..9456444 100644
--- a/src/lib/IWAMessage.cpp
+++ b/src/lib/IWAMessage.cpp
@@ -42,7 +42,8 @@ IWAMessage::IWAMessage(const RVNGInputStreamPtr_t &input, unsigned long length)
   : m_input(input)
   , m_fields()
 {
-  assert(length > 0);
+  if (length == 0)
+    return;
 
   parse(length);
 }