1 files changed, 143 insertions, 0 deletions
diff --git a/libqpdf/SparseOHArray.cc b/libqpdf/SparseOHArray.cc
new file mode 100644
index 00000000..2c525ca8
--- /dev/null
+++ b/libqpdf/SparseOHArray.cc
@@ -0,0 +1,143 @@
+#include <qpdf/SparseOHArray.hh>
+#include <stdexcept>
+
+SparseOHArray::SparseOHArray() :
+    n_elements(0)
+{
+}
+
+size_t
+SparseOHArray::size() const
+{
+    return this->n_elements;
+}
+
+void
+SparseOHArray::append(QPDFObjectHandle oh)
+{
+    if (! oh.isResolvedNull())
+    {
+        this->elements[this->n_elements] = oh;
+    }
+    ++this->n_elements;
+}
+
+QPDFObjectHandle
+SparseOHArray::at(size_t idx) const
+{
+    if (idx >= this->n_elements)
+    {
+	throw std::logic_error(
+	    "INTERNAL ERROR: bounds error accessing SparseOHArray element");
+    }
+    std::map<size_t, QPDFObjectHandle>::const_iterator iter =
+        this->elements.find(idx);
+    if (iter == this->elements.end())
+    {
+        return QPDFObjectHandle::newNull();
+    }
+    else
+    {
+        return (*iter).second;
+    }
+}
+
+void
+SparseOHArray::remove_last()
+{
+    if (this->n_elements == 0)
+    {
+	throw std::logic_error(
+	    "INTERNAL ERROR: attempt to remove"
+            " last item from empty SparseOHArray");
+    }
+    --this->n_elements;
+    this->elements.erase(this->n_elements);
+}
+
+void
+SparseOHArray::releaseResolved()
+{
+    for (std::map<size_t, QPDFObjectHandle>::iterator iter =
+             this->elements.begin();
+	 iter != this->elements.end(); ++iter)
+    {
+	QPDFObjectHandle::ReleaseResolver::releaseResolved((*iter).second);
+    }
+}
+
+void
+SparseOHArray::setAt(size_t idx, QPDFObjectHandle oh)
+{
+    if (idx >= this->n_elements)
+    {
+	throw std::logic_error("bounds error setting item in SparseOHArray");
+    }
+    if (oh.isResolvedNull())
+    {
+        this->elements.erase(idx);
+    }
+    else
+    {
+        this->elements[idx] = oh;
+    }
+}
+
+void
+SparseOHArray::erase(size_t idx)
+{
+    if (idx >= this->n_elements)
+    {
+	throw std::logic_error("bounds error erasing item from SparseOHArray");
+    }
+    std::map<size_t, QPDFObjectHandle> dest;
+    for (std::map<size_t, QPDFObjectHandle>::iterator iter =
+             this->elements.begin();
+	 iter != this->elements.end(); ++iter)
+    {
+        if ((*iter).first < idx)
+        {
+            dest.insert(*iter);
+        }
+        else if ((*iter).first > idx)
+        {
+            dest[(*iter).first - 1] = (*iter).second;
+        }
+    }
+    this->elements = dest;
+    --this->n_elements;
+}
+
+void
+SparseOHArray::insert(size_t idx, QPDFObjectHandle oh)
+{
+    if (idx > this->n_elements)
+    {
+        throw std::logic_error("bounds error inserting item to SparseOHArray");
+    }
+    else if (idx == this->n_elements)
+    {
+        // Allow inserting to the last position
+        append(oh);
+    }
+    else
+    {
+        std::map<size_t, QPDFObjectHandle> dest;
+        for (std::map<size_t, QPDFObjectHandle>::iterator iter =
+                 this->elements.begin();
+             iter != this->elements.end(); ++iter)
+        {
+            if ((*iter).first < idx)
+            {
+                dest.insert(*iter);
+            }
+            else
+            {
+                dest[(*iter).first + 1] = (*iter).second;
+            }
+        }
+        this->elements = dest;
+        this->elements[idx] = oh;
+        ++this->n_elements;
+    }
+}