Handle inheritable page attributes

Add getAttribute for handling inheritable page attributes, and fix
getPageImages and annotation flattening code to use it.

1 files changed, 4 insertions, 16 deletions

diff --git a/libqpdf/QPDFObjectHandle.cc b/libqpdf/QPDFObjectHandle.cc
index a0d45c86..b802a55c 100644
--- a/libqpdf/QPDFObjectHandle.cc
+++ b/libqpdf/QPDFObjectHandle.cc
@@ -18,6 +18,7 @@
 #include <qpdf/Pl_QPDFTokenizer.hh>
 #include <qpdf/BufferInputSource.hh>
 #include <qpdf/QPDFExc.hh>
+#include <qpdf/QPDFPageObjectHelper.hh>
 
 #include <qpdf/QTC.hh>
 #include <qpdf/QUtil.hh>
@@ -1109,24 +1110,11 @@ QPDFObjectHandle::getGeneration() const
 std::map<std::string, QPDFObjectHandle>
 QPDFObjectHandle::getPageImages()
 {
-    // Note: this code doesn't handle inherited resources.  If this
-    // page dictionary doesn't have a /Resources key or has one whose
-    // value is null or an empty dictionary, you are supposed to walk
-    // up the page tree until you find a /Resources dictionary.  As of
-    // this writing, I don't have any test files that use inherited
-    // resources, and hand-generating one won't be a good test because
-    // any mistakes in my understanding would be present in both the
-    // code and the test file.
-
-    // NOTE: If support of inherited resources (see above comment) is
-    // implemented, edit comment in QPDFObjectHandle.hh for this
-    // function.  Also remove call to pushInheritedAttributesToPage
-    // from qpdf.cc when show_page_images is true.
-
     std::map<std::string, QPDFObjectHandle> result;
-    if (this->hasKey("/Resources"))
+    QPDFObjectHandle resources =
+        QPDFPageObjectHelper(*this).getAttribute("/Resources", false);
+    if (resources.isDictionary())
     {
-	QPDFObjectHandle resources = this->getKey("/Resources");
 	if (resources.hasKey("/XObject"))
 	{
 	    QPDFObjectHandle xobject = resources.getKey("/XObject");