From c40f8b5329a645bd7ec2202af3433d11e6eae1d8 Mon Sep 17 00:00:00 2001
From: Jay Berkenbilt <ejb@ql.org>
Date: Fri, 17 Dec 2021 12:34:48 -0500
Subject: [PATCH] Make object types available to C API

---
 ChangeLog                  |  4 ++++
 include/qpdf/Constants.h   | 28 +++++++++++++++++++++++
 include/qpdf/QPDFObject.hh | 47 +++++++++++++++++++-------------------
 3 files changed, 56 insertions(+), 23 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index 60e3c0c2..cad0edd3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2021-12-17  Jay Berkenbilt  <ejb@ql.org>
 
+	* QPDFObjectHandle object types have been moved from
+	QPDFObject::object_type_e to qpdf_object_type_e (defined in
+	Constants.h). Old values are available for backward compatibility.
+
 	* Add Pl_Buffer::getMallocBuffer() to initialize a buffer with
 	malloc in support of the C API
 
diff --git a/include/qpdf/Constants.h b/include/qpdf/Constants.h
index 4e4c9e01..3e36a8f9 100644
--- a/include/qpdf/Constants.h
+++ b/include/qpdf/Constants.h
@@ -41,6 +41,34 @@ enum qpdf_error_code_e
     qpdf_e_object,              /* type/bounds errors accessing objects */
 };
 
+/* Object Types */
+
+/* PDF objects represented by QPDFObjectHandle or, in the C API, by
+ * qpdf_oh, have a unique type code that has one of the values in the
+ * list below. As new object types are added to qpdf, additional items
+ * may be added to the list, so code that switches on these values
+ * should take that into consideration.
+ */
+enum qpdf_object_type_e {
+    /* Object types internal to qpdf */
+    qpdf_ot_uninitialized,
+    qpdf_ot_reserved,
+    /* Object types that can occur in the main document */
+    qpdf_ot_null,
+    qpdf_ot_boolean,
+    qpdf_ot_integer,
+    qpdf_ot_real,
+    qpdf_ot_string,
+    qpdf_ot_name,
+    qpdf_ot_array,
+    qpdf_ot_dictionary,
+    qpdf_ot_stream,
+    /* Additional object types that can occur in content streams */
+    qpdf_ot_operator,
+    qpdf_ot_inlineimage,
+    /* NOTE: if adding to this list, update QPDFObject.hh */
+};
+
 /* Write Parameters. See QPDFWriter.hh for details. */
 
 enum qpdf_object_stream_e
diff --git a/include/qpdf/QPDFObject.hh b/include/qpdf/QPDFObject.hh
index 3b1cd72b..02f51ab2 100644
--- a/include/qpdf/QPDFObject.hh
+++ b/include/qpdf/QPDFObject.hh
@@ -25,6 +25,7 @@
 #include <qpdf/DLL.h>
 #include <qpdf/Types.h>
 #include <qpdf/JSON.hh>
+#include <qpdf/Constants.h>
 
 #include <string>
 
@@ -37,29 +38,29 @@ class QPDF_DLL_CLASS QPDFObject
     QPDFObject();
 
     // Objects derived from QPDFObject are accessible through
-    // QPDFObjectHandle.  Each object returns a unique type code that
-    // has one of the values in the list below.  As new object types
-    // are added to qpdf, additional items may be added to the list,
-    // so code that switches on these values should take that into
-    // consideration.
-    enum object_type_e {
-        // Object types internal to qpdf
-        ot_uninitialized,
-        ot_reserved,
-        // Object types that can occur in the main document
-        ot_null,
-        ot_boolean,
-        ot_integer,
-        ot_real,
-        ot_string,
-        ot_name,
-        ot_array,
-        ot_dictionary,
-        ot_stream,
-        // Additional object types that can occur in content streams
-        ot_operator,
-        ot_inlineimage,
-    };
+    // QPDFObjectHandle. Each object returns a unique type code that
+    // has one of the valid qpdf_object_type_e values. As new object
+    // types are added to qpdf, additional items may be added to the
+    // list, so code that switches on these values should take that
+    // into consideration.
+
+    // Prior to qpdf 10.5, qpdf_object_type_e was
+    // QPDFObject::object_type_e but was moved to make it accessible
+    // to the C API. The code below is for backward compatibility.
+    typedef enum qpdf_object_type_e object_type_e;
+    static constexpr object_type_e ot_uninitialized = ::qpdf_ot_uninitialized;
+    static constexpr object_type_e ot_reserved = ::qpdf_ot_reserved;
+    static constexpr object_type_e ot_null = ::qpdf_ot_null;
+    static constexpr object_type_e ot_boolean = ::qpdf_ot_boolean;
+    static constexpr object_type_e ot_integer = ::qpdf_ot_integer;
+    static constexpr object_type_e ot_real = ::qpdf_ot_real;
+    static constexpr object_type_e ot_string = ::qpdf_ot_string;
+    static constexpr object_type_e ot_name = ::qpdf_ot_name;
+    static constexpr object_type_e ot_array = ::qpdf_ot_array;
+    static constexpr object_type_e ot_dictionary = ::qpdf_ot_dictionary;
+    static constexpr object_type_e ot_stream = ::qpdf_ot_stream;
+    static constexpr object_type_e ot_operator = ::qpdf_ot_operator;
+    static constexpr object_type_e ot_inlineimage = ::qpdf_ot_inlineimage;
 
     virtual ~QPDFObject() {}
     virtual std::string unparse() = 0;