More robust handling of type errors

Give objects descriptions and context so it is possible to issue
warnings instead of fatal errors for attempts to access objects of the
wrong type.

1 files changed, 31 insertions, 0 deletions

diff --git a/libqpdf/QPDF_Stream.cc b/libqpdf/QPDF_Stream.cc
index 7b84d10c..384652e2 100644
--- a/libqpdf/QPDF_Stream.cc
+++ b/libqpdf/QPDF_Stream.cc
@@ -39,6 +39,7 @@ QPDF_Stream::QPDF_Stream(QPDF* qpdf, int objid, int generation,
 	    "stream object instantiated with non-dictionary "
 	    "object for dictionary");
     }
+    setStreamDescription();
 }
 
 QPDF_Stream::~QPDF_Stream()
@@ -85,6 +86,35 @@ QPDF_Stream::getTypeName() const
     return "stream";
 }
 
+void
+QPDF_Stream::setDescription(QPDF* qpdf, std::string const& description)
+{
+    this->QPDFObject::setDescription(qpdf, description);
+    setDictDescription();
+}
+
+void
+QPDF_Stream::setStreamDescription()
+{
+    setDescription(
+        this->qpdf,
+        "stream object " + QUtil::int_to_string(this->objid) + " " +
+        QUtil::int_to_string(this->generation));
+}
+
+void
+QPDF_Stream::setDictDescription()
+{
+    QPDF* qpdf = 0;
+    std::string description;
+    if ((! this->stream_dict.hasObjectDescription()) &&
+        getDescription(qpdf, description))
+    {
+        this->stream_dict.setObjectDescription(
+            qpdf, description + " -> stream dictionary");
+    }
+}
+
 QPDFObjectHandle
 QPDF_Stream::getDict() const
 {
@@ -688,6 +718,7 @@ void
 QPDF_Stream::replaceDict(QPDFObjectHandle new_dict)
 {
     this->stream_dict = new_dict;
+    setDictDescription();
     QPDFObjectHandle length_obj = new_dict.getKey("/Length");
     if (length_obj.isInteger())
     {