Handle page tree node with no /Type

Original reported here:
https://bugs.launchpad.net/ubuntu/+source/qpdf/+bug/1397413

The PDF specification says that the /Type key for nodes in the pages
dictionary (both /Page and /Pages) is required, but some PDF files
omit them. Use the presence of other keys to determine the type of
pages tree node this is if the type key is not found.

1 files changed, 14 insertions, 1 deletions

diff --git a/libqpdf/QPDF_pages.cc b/libqpdf/QPDF_pages.cc
index e8d107b3..44db064c 100644
--- a/libqpdf/QPDF_pages.cc
+++ b/libqpdf/QPDF_pages.cc
@@ -56,7 +56,20 @@ void
 QPDF::getAllPagesInternal(QPDFObjectHandle cur_pages,
 			  std::vector<QPDFObjectHandle>& result)
 {
-    std::string type = cur_pages.getKey("/Type").getName();
+    std::string type;
+    QPDFObjectHandle type_key = cur_pages.getKey("/Type");
+    if (type_key.isName())
+    {
+        type = type_key.getName();
+    }
+    else if (cur_pages.hasKey("/Kids"))
+    {
+        type = "/Pages";
+    }
+    else
+    {
+        type = "/Page";
+    }
     if (type == "/Pages")
     {
 	QPDFObjectHandle kids = cur_pages.getKey("/Kids");