Write offsets as unsigned in linearization hint tables (fixes #1023)

3 files changed, 13 insertions, 4 deletions

diff --git a/ChangeLog b/ChangeLog
index 2674cc06..22068042 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2023-10-14  Jay Berkenbilt  <ejb@ql.org>
 
+        * Tweak linearization code to better handle files between 2 GB and
+        4 GB in size. Fixes #1023.
+
         * Fix serious bug: qpdf could discard a the character after an
         escaped octal string. For content, this would only happen with QDF
         or when normalizing content, but it could have happened in a
diff --git a/include/qpdf/QPDF.hh b/include/qpdf/QPDF.hh
index 0281f5d0..2ca6005c 100644
--- a/include/qpdf/QPDF.hh
+++ b/include/qpdf/QPDF.hh
@@ -1437,6 +1437,12 @@ class QPDF
     {
         return QIntC::to_int(i);
     }
+    template <typename T>
+    static unsigned long long
+    toULL(T const& i)
+    {
+        return QIntC::to_ulonglong(i);
+    }
 
     class Members
     {
diff --git a/libqpdf/QPDF_linearization.cc b/libqpdf/QPDF_linearization.cc
index fe25c6d9..469b9933 100644
--- a/libqpdf/QPDF_linearization.cc
+++ b/libqpdf/QPDF_linearization.cc
@@ -1670,11 +1670,11 @@ QPDF::writeHPageOffset(BitWriter& w)
     HPageOffset& t = m->page_offset_hints;
 
     w.writeBitsInt(t.min_nobjects, 32);               // 1
-    w.writeBitsInt(toI(t.first_page_offset), 32);     // 2
+    w.writeBits(toULL(t.first_page_offset), 32);      // 2
     w.writeBitsInt(t.nbits_delta_nobjects, 16);       // 3
     w.writeBitsInt(t.min_page_length, 32);            // 4
     w.writeBitsInt(t.nbits_delta_page_length, 16);    // 5
-    w.writeBitsInt(t.min_content_offset, 32);         // 6
+    w.writeBits(toULL(t.min_content_offset), 32);     // 6
     w.writeBitsInt(t.nbits_delta_content_offset, 16); // 7
     w.writeBitsInt(t.min_content_length, 32);         // 8
     w.writeBitsInt(t.nbits_delta_content_length, 16); // 9
@@ -1717,7 +1717,7 @@ QPDF::writeHSharedObject(BitWriter& w)
     HSharedObject& t = m->shared_object_hints;
 
     w.writeBitsInt(t.first_shared_obj, 32);         // 1
-    w.writeBitsInt(toI(t.first_shared_offset), 32); // 2
+    w.writeBits(toULL(t.first_shared_offset), 32);  // 2
     w.writeBitsInt(t.nshared_first_page, 32);       // 3
     w.writeBitsInt(t.nshared_total, 32);            // 4
     w.writeBitsInt(t.nbits_nobjects, 16);           // 5
@@ -1749,7 +1749,7 @@ void
 QPDF::writeHGeneric(BitWriter& w, HGeneric& t)
 {
     w.writeBitsInt(t.first_object, 32);             // 1
-    w.writeBitsInt(toI(t.first_object_offset), 32); // 2
+    w.writeBits(toULL(t.first_object_offset), 32);  // 2
     w.writeBitsInt(t.nobjects, 32);                 // 3
     w.writeBitsInt(t.group_length, 32);             // 4
 }