Improve getCompressibleObjGens fix to handle gen > 0

This commit is contained in:
Jay Berkenbilt 2024-01-07 15:21:38 -05:00
parent ba477e0b33
commit df61f3a6c6
1 changed files with 9 additions and 3 deletions

View File

@ -2378,6 +2378,7 @@ QPDF::getCompressibleObjGens()
const size_t max_obj = getObjectCount();
std::vector<bool> visited(max_obj, false);
QPDFObjGen::set visited_gen; // for objects with generation > 0
std::vector<QPDFObjectHandle> queue;
queue.reserve(512);
queue.push_back(m->trailer);
@ -2388,14 +2389,19 @@ QPDF::getCompressibleObjGens()
if (obj.isIndirect()) {
QPDFObjGen og = obj.getObjGen();
const size_t id = toS(og.getObj() - 1);
const int gen = og.getGen();
if (id >= max_obj)
throw std::runtime_error(
throw std::logic_error(
"unexpected object id encountered in getCompressibleObjGens");
if (visited[id]) {
if ((gen == 0 && visited[id]) || visited_gen.count(og)) {
QTC::TC("qpdf", "QPDF loop detected traversing objects");
continue;
}
visited[id] = true;
if (gen == 0) {
visited[id] = true;
} else {
visited_gen.insert(og);
}
if (og == encryption_dict_og) {
QTC::TC("qpdf", "QPDF exclude encryption dictionary");
} else if (!(obj.isStream() ||