From bee967b99ab8261c928580c4f78150863627a242 Mon Sep 17 00:00:00 2001
From: liuli0217 <67736340+liuli0217@users.noreply.github.com>
Date: Thu, 2 Jul 2020 17:42:13 +0800
Subject: [PATCH] fix: get inheritable attribute from parent

when /mediabox is inherited from parent, can't get rect.
---
 filter/pdf.cxx | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/filter/pdf.cxx b/filter/pdf.cxx
index 51b5fcb64..68b1af912 100644
--- a/filter/pdf.cxx
+++ b/filter/pdf.cxx
@@ -217,14 +217,25 @@ extern "C" void pdf_add_type1_font(pdf_t *pdf,
  */
 static bool dict_lookup_rect(QPDFObjectHandle object,
                              std::string const& key,
-                             float rect[4])
+                             float rect[4],
+                             bool inheritable)
 {
   // preliminary checks
-  if (!object.isDictionary() || !object.hasKey(key))
+  if (!object.isDictionary())
     return false;
+  
+  QPDFObjectHandle value;
+  if (!object.hasKey(key) && inheritable){
+    QPDFFormFieldObjectHelper helper(object);
+    value = helper.getInheritableFieldValue(key);
+    if (value.isNull()) {
+      return false;
+    }
+  } else {
+    value = object.getKey(key);
+  }
 
   // check if the key is array or some other type
-  QPDFObjectHandle value = object.getKey(key);
   if (!value.isArray())
     return false;
   
@@ -289,7 +300,7 @@ extern "C" void pdf_resize_page (pdf_t *pdf,
   float old_mediabox[4];
   QPDFObjectHandle media_box;
 
-  if (!dict_lookup_rect(page, "/MediaBox", old_mediabox)) {
+  if (!dict_lookup_rect(page, "/MediaBox", old_mediabox, true)) {
     fprintf(stderr, "ERROR: pdf doesn't contain a valid mediabox\n");
     return;
   }
-- 
2.47.2