C API: qpdf_oh_is_initialized

ChangeLog

@@ -1,5 +1,7 @@
 2021-12-02  Jay Berkenbilt  <ejb@ql.org>
 
+	* C API: Add qpdf_oh_is_initialized.
+
 	* C API: Add qpdf_get_last_string_length to return the length of
 	the last string returned. This is necessary in order to fully
 	retrieve values of strings that may contain embedded null characters.

include/qpdf/qpdf-c.h

@@ -581,6 +581,8 @@ extern "C" {
      * to.
      */
 
+    QPDF_DLL
+    QPDF_BOOL qpdf_oh_is_initialized(qpdf_data data, qpdf_oh oh);
     QPDF_DLL
     QPDF_BOOL qpdf_oh_is_bool(qpdf_data data, qpdf_oh oh);
     QPDF_DLL

libqpdf/qpdf-c.cc

@@ -881,8 +881,7 @@ qpdf_oh_valid_internal(qpdf_data qpdf, qpdf_oh oh)
 {
     auto i = qpdf->oh_cache.find(oh);
     bool result = ((i != qpdf->oh_cache.end()) &&
-                   (i->second).getPointer() &&
+                   (i->second).getPointer());
-                   (i->second)->isInitialized());
     if (! result)
     {
         QTC::TC("qpdf", "qpdf-c invalid object handle");
@@ -892,11 +891,18 @@ qpdf_oh_valid_internal(qpdf_data qpdf, qpdf_oh oh)
                 qpdf->qpdf->getFilename(),
                 std::string("C API object handle ") +
                 QUtil::uint_to_string(oh),
-                0, "attempted access to unknown/uninitialized object handle"));
+                0, "attempted access to unknown object handle"));
     }
     return result;
 }
 
+QPDF_BOOL qpdf_oh_is_initialized(qpdf_data qpdf, qpdf_oh oh)
+{
+    QTC::TC("qpdf", "qpdf-c called qpdf_oh_is_initialized");
+    return (qpdf_oh_valid_internal(qpdf, oh) &&
+            qpdf->oh_cache[oh]->isInitialized());
+}
+
 QPDF_BOOL qpdf_oh_is_bool(qpdf_data qpdf, qpdf_oh oh)
 {
     QTC::TC("qpdf", "qpdf-c called qpdf_oh_is_bool");

manual/qpdf-manual.xml

@@ -5133,6 +5133,13 @@ print "\n";
           embedded null characters.
          </para>
         </listitem>
+        <listitem>
+         <para>
+          Add <function>qpdf_oh_is_initialized</function> to the
+          C API. While you can't directly create uninitialized objects
+          from the C API, you still have to be able to detect them.
+         </para>
+        </listitem>
        </itemizedlist>
       </listitem>
      </itemizedlist>

qpdf/qpdf-ctest.c

@@ -512,6 +512,7 @@ static void test24(char const* infile,
            qpdf_oh_get_object_id(qpdf, root_from_trailer));
     qpdf_oh pages = qpdf_oh_get_key(qpdf, root, "/Pages");
     assert(qpdf_oh_is_dictionary(qpdf, pages));
+    assert(qpdf_oh_is_initialized(qpdf, pages));
     qpdf_oh kids = qpdf_oh_get_key(qpdf, pages, "/Kids");
     assert(qpdf_oh_is_array(qpdf, kids));
     assert(qpdf_oh_get_array_n_items(qpdf, kids) == 1);
@@ -687,6 +688,12 @@ static void test24(char const* infile,
     qpdf_set_suppress_original_object_IDs(qpdf, QPDF_TRUE);
     qpdf_write(qpdf);
     report_errors();
+
+    /* Make sure we detect uninitialized objects */
+    qpdf_data qpdf2 = qpdf_init();
+    trailer = qpdf_get_trailer(qpdf2);
+    assert(! qpdf_oh_is_initialized(qpdf2, trailer));
+    qpdf_cleanup(&qpdf2);
 }
 
 int main(int argc, char* argv[])

qpdf/qpdf.testcov

@@ -600,3 +600,4 @@ QPDF_pages findPage not found 0
 qpdf overlay page with no resources 0
 QPDFObjectHandle check ownership 0
 qpdf weak crypto warning 0
+qpdf-c called qpdf_oh_is_initialized 0

qpdf/qtest/qpdf/c-object-handles.out

@@ -7,18 +7,18 @@ item 0: 0 0.00
 item 1: 0 0.00
 item 2: 612 612.00
 item 3: 792 792.00
-warning: minimal.pdf (C API object handle 6): attempted access to unknown/uninitialized object handle
+warning: minimal.pdf (C API object handle 6): attempted access to unknown object handle
   code: 5
   file: minimal.pdf
   pos : 0
-  text: attempted access to unknown/uninitialized object handle
+  text: attempted access to unknown object handle
-warning: minimal.pdf (C API object handle 9): attempted access to unknown/uninitialized object handle
+warning: minimal.pdf (C API object handle 9): attempted access to unknown object handle
   code: 5
   file: minimal.pdf
   pos : 0
-  text: attempted access to unknown/uninitialized object handle
+  text: attempted access to unknown object handle
-warning: minimal.pdf (C API object handle 9): attempted access to unknown/uninitialized object handle
+warning: minimal.pdf (C API object handle 9): attempted access to unknown object handle
   code: 5
   file: minimal.pdf
   pos : 0
-  text: attempted access to unknown/uninitialized object handle
+  text: attempted access to unknown object handle