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, 16 insertions, 3 deletions

diff --git a/libqpdf/QPDF_Dictionary.cc b/libqpdf/QPDF_Dictionary.cc
index 0af2f4bf..df640354 100644
--- a/libqpdf/QPDF_Dictionary.cc
+++ b/libqpdf/QPDF_Dictionary.cc
@@ -51,6 +51,12 @@ QPDF_Dictionary::getTypeName() const
     return "dictionary";
 }
 
+void
+QPDF_Dictionary::setDescription(QPDF* qpdf, std::string const& description)
+{
+    this->QPDFObject::setDescription(qpdf, description);
+}
+
 bool
 QPDF_Dictionary::hasKey(std::string const& key)
 {
@@ -70,7 +76,15 @@ QPDF_Dictionary::getKey(std::string const& key)
     }
     else
     {
-	return QPDFObjectHandle::newNull();
+        QPDFObjectHandle null = QPDFObjectHandle::newNull();
+        QPDF* qpdf = 0;
+        std::string description;
+        if (getDescription(qpdf, description))
+        {
+            null.setObjectDescription(
+                qpdf, description + " -> dictionary key " + key);
+        }
+	return null;
     }
 }
 
@@ -93,13 +107,12 @@ QPDF_Dictionary::getKeys()
 std::map<std::string, QPDFObjectHandle> const&
 QPDF_Dictionary::getAsMap() const
 {
-
     return this->items;
 }
 
 void
 QPDF_Dictionary::replaceKey(std::string const& key,
-			    QPDFObjectHandle const& value)
+			    QPDFObjectHandle value)
 {
     // add or replace value
     this->items[key] = value;