name/number trees: insertAfter

include/qpdf/QPDFNameTreeObjectHelper.hh

@@ -112,6 +112,19 @@ class QPDFNameTreeObjectHelper: public QPDFObjectHelper
             return ! operator==(other);
         }
 
+        // DANGER: this method can create inconsistent trees if not
+        // used properly! Insert a new item immediately after the
+        // current iterator and increment so that it points to the new
+        // item. If the current iterator is end(), insert at the
+        // beginning. This method does not check for proper ordering,
+        // so if you use it, you must ensure that the item you are
+        // inserting belongs where you are putting it. The reason for
+        // this method is that it is more efficient than insert() and
+        // can be used safely when you are creating a new tree and
+        // inserting items in sorted order.
+        QPDF_DLL
+        void insertAfter(std::string const& key, QPDFObjectHandle value);
+
       private:
         iterator(std::shared_ptr<NNTreeIterator> const&);
         std::shared_ptr<NNTreeIterator> impl;

include/qpdf/QPDFNumberTreeObjectHelper.hh

@@ -131,6 +131,19 @@ class QPDFNumberTreeObjectHelper: public QPDFObjectHelper
             return ! operator==(other);
         }
 
+        // DANGER: this method can create inconsistent trees if not
+        // used properly! Insert a new item immediately after the
+        // current iterator and increment so that it points to the new
+        // item. If the current iterator is end(), insert at the
+        // beginning. This method does not check for proper ordering,
+        // so if you use it, you must ensure that the item you are
+        // inserting belongs where you are putting it. The reason for
+        // this method is that it is more efficient than insert() and
+        // can be used safely when you are creating a new tree and
+        // inserting items in sorted order.
+        QPDF_DLL
+        void insertAfter(numtree_number key, QPDFObjectHandle value);
+
       private:
         iterator(std::shared_ptr<NNTreeIterator> const&);
         std::shared_ptr<NNTreeIterator> impl;

libqpdf/NNTree.cc

@@ -444,6 +444,14 @@ NNTreeIterator::lastPathElement()
 void
 NNTreeIterator::insertAfter(QPDFObjectHandle key, QPDFObjectHandle value)
 {
+    if (! valid())
+    {
+        QTC::TC("qpdf", "NNTree insertAfter inserts first");
+        impl.insertFirst(key, value);
+        deepen(impl.oh, true, false);
+        return;
+    }
+
     auto items = this->node.getKey(impl.details.itemsKey());
     if (! items.isArray())
     {
@@ -457,6 +465,7 @@ NNTreeIterator::insertAfter(QPDFObjectHandle key, QPDFObjectHandle value)
     items.insertItem(this->item_number + 3, value);
     resetLimits(this->node, lastPathElement());
     split(this->node, lastPathElement());
+    increment(false);
 }
 
 NNTreeIterator&
@@ -968,7 +977,6 @@ NNTreeImpl::insert(QPDFObjectHandle key, QPDFObjectHandle value)
     {
         QTC::TC("qpdf", "NNTree insert inserts after");
         iter.insertAfter(key, value);
-        ++iter;
     }
     return iter;
 }

libqpdf/QPDFNameTreeObjectHelper.cc

@@ -102,6 +102,13 @@ QPDFNameTreeObjectHelper::iterator::operator==(iterator const& other) const
     return *(impl) == *(other.impl);
 }
 
+void
+QPDFNameTreeObjectHelper::iterator::insertAfter(
+    std::string const& key, QPDFObjectHandle value)
+{
+    impl->insertAfter(QPDFObjectHandle::newUnicodeString(key), value);
+}
+
 QPDFNameTreeObjectHelper::iterator
 QPDFNameTreeObjectHelper::begin() const
 {

libqpdf/QPDFNumberTreeObjectHelper.cc

@@ -98,6 +98,13 @@ QPDFNumberTreeObjectHelper::iterator::operator==(iterator const& other) const
     return *(impl) == *(other.impl);
 }
 
+void
+QPDFNumberTreeObjectHelper::iterator::insertAfter(
+    numtree_number key, QPDFObjectHandle value)
+{
+    impl->insertAfter(QPDFObjectHandle::newInteger(key), value);
+}
+
 QPDFNumberTreeObjectHelper::iterator
 QPDFNumberTreeObjectHelper::begin() const
 {

qpdf/qpdf.testcov

@@ -552,3 +552,4 @@ NNTree bad node during find 0
 NNTree node is not a dictionary 0
 NNTree limits didn't change 0
 NNTree increment end() 0
+NNTree insertAfter inserts first 0

qpdf/qtest/qpdf/name-tree.out

@@ -16,6 +16,9 @@
 20 twenty -> twenty.
 22 twenty-two -> twenty-two!
 29 twenty-nine -> twenty-nine!
+insertAfter
+3 (3!)
+4 (4!)
 /Empty1
 /Empty2
 /Bad1: deprecated API

qpdf/qtest/qpdf/number-tree.out

@@ -26,6 +26,9 @@
 22 twenty-two
 23 twenty-three
 29 twenty-nine
+insertAfter
+3 (3!)
+4 (4!)
 /Bad1: deprecated API
 /Bad1
 WARNING: number-tree.pdf (Name/Number tree node (object 14)): name/number tree node has neither non-empty /Nums nor /Kids

qpdf/test_driver.cc

@@ -1802,6 +1802,19 @@ void runtest(int n, char const* filename1, char const* arg2)
         --iter1;
         assert((*iter1).first == 2);
 
+        std::cout << "insertAfter" << std::endl;
+        auto new2 = QPDFNumberTreeObjectHelper::newEmpty(pdf);
+        auto iter2 = new2.begin();
+        assert(iter2 == new2.end());
+        iter2.insertAfter(3, QPDFObjectHandle::newString("3!"));
+        assert((*iter2).first == 3);
+        iter2.insertAfter(4, QPDFObjectHandle::newString("4!"));
+        assert((*iter2).first == 4);
+        for (auto i: new2)
+        {
+            std::cout << i.first << " " << i.second.unparse() << std::endl;
+        }
+
         // Exercise deprecated API until qpdf 11
         std::cout << "/Bad1: deprecated API" << std::endl;
         auto bad1 = QPDFNumberTreeObjectHelper(
@@ -1961,6 +1974,19 @@ void runtest(int n, char const* filename1, char const* arg2)
         --iter1;
         assert((*iter1).first == "2");
 
+        std::cout << "insertAfter" << std::endl;
+        auto new2 = QPDFNameTreeObjectHelper::newEmpty(pdf);
+        auto iter2 = new2.begin();
+        assert(iter2 == new2.end());
+        iter2.insertAfter("3", QPDFObjectHandle::newString("3!"));
+        assert((*iter2).first == "3");
+        iter2.insertAfter("4", QPDFObjectHandle::newString("4!"));
+        assert((*iter2).first == "4");
+        for (auto i: new2)
+        {
+            std::cout << i.first << " " << i.second.unparse() << std::endl;
+        }
+
         std::vector<std::string> empties = {"/Empty1", "/Empty2"};
         for (auto const& k: empties)
         {