Add temporary methods QPDF::Xref_table::size and as_map

Also, remove redundant clearing of the xref tabl during QPDF destruction.

Add temporary methods QPDF::Xref_table::size and as_map
Also, remove redundant clearing of the xref tabl during QPDF destruction.
m-holger
1 parent fa03ed38
Showing 3 changed files with 21 additions and 11 deletions
libqpdf/QPDF.cc
libqpdf/QPDF_linearization.cc
libqpdf/qpdf/QPDF_private.hh
@@ -227,9 +227,6 @@ QPDF::~QPDF()
     // are reachable from this object to release their association with this QPDF. Direct objects
     // are not destroyed since they can be moved to other QPDF objects safely.
-    // At this point, obviously no one is still using the QPDF object, but we'll explicitly clear
-    // the xref table anyway just to prevent any possibility of resolve() succeeding.
-    m->xref_table.clear();
     for (auto const& iter: m->obj_cache) {
         iter.second.object->disconnect();
         if (iter.second.object->getTypeCode() != ::ot_null) {
@@ -1651,7 +1648,7 @@ QPDF::recoverStreamLength(
         QPDFObjGen found_og;
         // Make sure this is inside this object
-        for (auto const& [current_og, entry]: m->xref_table) {
+        for (auto const& [current_og, entry]: m->xref_table.as_map()) {
             if (entry.getType() == 1) {
                 qpdf_offset_t obj_offset = entry.getOffset();
                 if (found_offset < obj_offset && obj_offset < end) {
@@ -1984,9 +1981,8 @@ QPDF::resolveObjectsInStream(int obj_stream_number)
     m->last_object_description += "object ";
     for (auto const& iter: offsets) {
         QPDFObjGen og(iter.first, 0);
-        auto entry = m->xref_table.find(og);
-        if (entry != m->xref_table.end() && entry->second.getType() == 2 &&
-            entry->second.getObjStreamNumber() == obj_stream_number) {
+        if (m->xref_table.type(og) == 2 &&
+            m->xref_table.stream_number(og.getObj()) == obj_stream_number) {
             int offset = iter.second;
             input->seek(offset, SEEK_SET);
             QPDFObjectHandle oh = readObjectInStream(input, iter.first);
@@ -2560,7 +2556,7 @@ QPDF::getXRefTableInternal()
         throw std::logic_error("QPDF::getXRefTable called before parsing.");
     }
-    return m->xref_table;
+    return m->xref_table.as_map();
 }
 size_t
@@ -2568,7 +2564,7 @@ QPDF::tableSize()
 {
     // If obj_cache is dense, accommodate all object in tables,else accommodate only original
     // objects.
-    auto max_xref = m->xref_table.size() ? m->xref_table.crbegin()->first.getObj() : 0;
+    auto max_xref = m->xref_table.size() ? m->xref_table.as_map().crbegin()->first.getObj() : 0;
     auto max_obj = m->obj_cache.size() ? m->obj_cache.crbegin()->first.getObj() : 0;
     auto max_id = std::numeric_limits<int>::max() - 1;
     if (max_obj >= max_id || max_xref >= max_id) {
@@ -486,7 +486,7 @@ QPDF::checkLinearizationInternal()
     // to figure out which objects are compressed and which are uncompressed.
     { // local scope
         std::map<int, int> object_stream_data;
-        for (auto const& iter: m->xref_table) {
+        for (auto const& iter: m->xref_table.as_map()) {
             QPDFObjGen const& og = iter.first;
             QPDFXRefEntry const& entry = iter.second;
             if (entry.getType() == 2) {
@@ -4,7 +4,7 @@
 #include <qpdf/QPDF.hh>
 // Xref_table encapsulates the pdf's xref table and trailer.
-class QPDF::Xref_table: public std::map<QPDFObjGen, QPDFXRefEntry>
+class QPDF::Xref_table: std::map<QPDFObjGen, QPDFXRefEntry>
 {
   public:
     Xref_table(QPDF& qpdf, InputSource* const& file) :
@@ -50,6 +50,20 @@ class QPDF::Xref_table: public std::map&lt;QPDFObjGen, QPDFXRefEntry&gt;
         return it == end() ? 0 : it->second.getObjStreamIndex();
     }
+    // Temporary access to underlying map
+    std::map<QPDFObjGen, QPDFXRefEntry> const&
+    as_map()
+    {
+        return *this;
+    }
+
+    // Temporary access to underlying map size
+    size_t
+    size() const noexcept
+    {
+        return trailer ? std::map<QPDFObjGen, QPDFXRefEntry>::size() : 0;
+    }
+
     QPDFObjectHandle trailer;
     bool reconstructed{false};
     // Various tables are indexed by object id, with potential size id + 1