Add method to get count of objects in QPDF

Jay Berkenbilt
1 parent c8183607
Showing 3 changed files with 26 additions and 9 deletions
ChangeLog
include/qpdf/QPDF.hh
libqpdf/QPDF.cc
 2018-06-22  Jay Berkenbilt  <ejb@ql.org>
+	* Add new method QPDF::getObjectCount(). This gives an approximate
+	(upper bound) account of objects in the QPDF object.
+
 	* Don't leave files open when merging. This makes it possible
 	merge more files at once than the operating system's open file
 	limit. Fixes #154.
@@ -431,6 +431,12 @@ class QPDF
     QPDF_DLL
     void showXRefTable();
+    // Return the approximate number of indirect objects. It is
+    // approximate because not all objects in the file are preserved
+    // in all cases.
+    QPDF_DLL
+    size_t getObjectCount();
+
     // Returns a list of indirect objects for every object in the xref
     // table. Useful for discovering objects that are not otherwise
     // referenced.
@@ -1218,6 +1218,22 @@ QPDF::showXRefTable()
     }
 }
+size_t
+QPDF::getObjectCount()
+{
+    // This method returns the next available indirect object number.
+    // makeIndirectObject uses it for this purpose.
+    QPDFObjGen o1(0, 0);
+    if (! this->m->obj_cache.empty())
+    {
+	o1 = (*(this->m->obj_cache.rbegin())).first;
+    }
+    QPDFObjGen o2 = (*(this->m->xref_table.rbegin())).first;
+    QTC::TC("qpdf", "QPDF indirect last obj from xref",
+	    (o2.getObj() > o1.getObj()) ? 1 : 0);
+    return std::max(o1.getObj(), o2.getObj());
+}
+
 std::vector<QPDFObjectHandle>
 QPDF::getAllObjects()
 {
@@ -1904,15 +1920,7 @@ QPDF::resolveObjectsInStream(int obj_stream_number)
 QPDFObjectHandle
 QPDF::makeIndirectObject(QPDFObjectHandle oh)
 {
-    QPDFObjGen o1(0, 0);
-    if (! this->m->obj_cache.empty())
-    {
-	o1 = (*(this->m->obj_cache.rbegin())).first;
-    }
-    QPDFObjGen o2 = (*(this->m->xref_table.rbegin())).first;
-    QTC::TC("qpdf", "QPDF indirect last obj from xref",
-	    (o2.getObj() > o1.getObj()) ? 1 : 0);
-    int max_objid = std::max(o1.getObj(), o2.getObj());
+    int max_objid = getObjectCount();
     QPDFObjGen next(max_objid + 1, 0);
     this->m->obj_cache[next] =
 	ObjCache(QPDFObjectHandle::ObjAccessor::getObject(oh), -1, -1);