Integrate `QPDFOutlineDocumentHelper` with `QPDF` for improved outline managemen…

…t. Add shared helper retrieval, validation methods, and update usages across the codebase.

Integrate `QPDFOutlineDocumentHelper` with `QPDF` for improved outline managemen…
…t. Add shared helper retrieval, validation methods, and update usages across the codebase.
m-holger
1 parent e6555a36
Showing 7 changed files with 48 additions and 6 deletions
examples/pdf-bookmarks.cc
fuzz/qpdf_outlines_fuzzer.cc
include/qpdf/QPDF.hh
include/qpdf/QPDFOutlineDocumentHelper.hh
libqpdf/QPDFJob.cc
libqpdf/QPDFOutlineDocumentHelper.cc
libqpdf/qpdf/QPDF_private.hh
@@ -177,7 +177,7 @@ main(int argc, char* argv[])
         QPDF qpdf;
         qpdf.processFile(filename, password);
-        QPDFOutlineDocumentHelper odh(qpdf);
+        auto& odh = QPDFOutlineDocumentHelper::get(qpdf);
         if (odh.hasOutlines()) {
             std::vector<int> numbers;
             if (show_targets) {
@@ -49,7 +49,7 @@ FuzzHelper::testOutlines()
 {
     std::shared_ptr<QPDF> q = getQpdf();
     std::list<std::vector<QPDFOutlineObjectHelper>> queue;
-    QPDFOutlineDocumentHelper odh(*q);
+    auto& odh = QPDFOutlineDocumentHelper::get(*q);
     queue.push_back(odh.getTopLevelOutlines());
     while (!queue.empty()) {
         for (auto& ol: *(queue.begin())) {
@@ -64,6 +64,7 @@ class QPDFLogger;
 class QPDFParser;
 class QPDFAcroFormDocumentHelper;
 class QPDFEmbeddedFileDocumentHelper;
+class QPDFOutlineDocumentHelper;
 class QPDFPageLabelDocumentHelper;
 class QPDF
@@ -802,6 +803,7 @@ class QPDF
     inline bool reconstructed_xref() const;
     inline QPDFAcroFormDocumentHelper& acroform();
     inline QPDFEmbeddedFileDocumentHelper& embedded_files();
+    inline QPDFOutlineDocumentHelper& outlines();
     inline QPDFPageLabelDocumentHelper& page_labels();
     // For testing only -- do not add to DLL
@@ -38,6 +38,21 @@
 class QPDFOutlineDocumentHelper: public QPDFDocumentHelper
 {
   public:
+    // Get a shared document helper for a given QPDF object.
+    //
+    // Retrieving a document helper for a QPDF object rather than creating a new one avoids repeated
+    // validation of the Acroform structure, which can be expensive.
+    QPDF_DLL
+    static QPDFOutlineDocumentHelper& get(QPDF& qpdf);
+
+    // Re-validate the Outlines structure. This is useful if you have modified the structure of the
+    // Outlines dictionary in a way that would invalidate the cache.
+    //
+    // If repair is true, the document will be repaired if possible if the validation encounters
+    // errors.
+    QPDF_DLL
+    void validate(bool repair = true);
+
     QPDF_DLL
     QPDFOutlineDocumentHelper(QPDF&);
@@ -17,7 +17,6 @@
 #include <qpdf/QPDFExc.hh>
 #include <qpdf/QPDFLogger.hh>
 #include <qpdf/QPDFObjectHandle_private.hh>
-#include <qpdf/QPDFOutlineDocumentHelper.hh>
 #include <qpdf/QPDFPageDocumentHelper.hh>
 #include <qpdf/QPDFPageObjectHelper.hh>
 #include <qpdf/QPDFSystemError.hh>
@@ -1051,7 +1050,7 @@ QPDFJob::doJSONPages(Pipeline* p, bool&amp; first, QPDF&amp; pdf)
     bool first_page = true;
     JSON::writeArrayOpen(p, first_page, 2);
     auto& pldh = pdf.page_labels();
-    QPDFOutlineDocumentHelper odh(pdf);
+    auto& odh = pdf.outlines();
     int pageno = -1;
     for (auto& ph: QPDFPageDocumentHelper(pdf).getAllPages()) {
         ++pageno;
@@ -1168,8 +1167,7 @@ QPDFJob::doJSONOutlines(Pipeline* p, bool&amp; first, QPDF&amp; pdf)
     }
     JSON j_outlines = JSON::makeArray();
-    QPDFOutlineDocumentHelper odh(pdf);
-    addOutlinesToJson(odh.getTopLevelOutlines(), j_outlines, page_numbers);
+    addOutlinesToJson(pdf.outlines().getTopLevelOutlines(), j_outlines, page_numbers);
     JSON::writeDictionaryItem(p, first, "outlines", j_outlines, 1);
 }
 #include <qpdf/QPDFOutlineDocumentHelper.hh>
 #include <qpdf/QPDFObjectHandle_private.hh>
+#include <qpdf/QPDF_private.hh>
 #include <qpdf/QTC.hh>
 class QPDFOutlineDocumentHelper::Members
@@ -27,6 +28,21 @@ QPDFOutlineDocumentHelper::QPDFOutlineDocumentHelper(QPDF&amp; qpdf) :
     QPDFDocumentHelper(qpdf),
     m(std::make_shared<Members>())
 {
+    validate();
+}
+
+QPDFOutlineDocumentHelper&
+QPDFOutlineDocumentHelper::get(QPDF& qpdf)
+{
+    return qpdf.outlines();
+}
+
+void
+QPDFOutlineDocumentHelper::validate(bool repair)
+{
+    m->outlines.clear();
+    m->names_dest = nullptr;
+
     QPDFObjectHandle root = qpdf.getRoot();
     if (!root.hasKey("/Outlines")) {
         return;
@@ -6,6 +6,7 @@
 #include <qpdf/QPDFAcroFormDocumentHelper.hh>
 #include <qpdf/QPDFEmbeddedFileDocumentHelper.hh>
 #include <qpdf/QPDFObject_private.hh>
+#include <qpdf/QPDFOutlineDocumentHelper.hh>
 #include <qpdf/QPDFPageLabelDocumentHelper.hh>
 #include <qpdf/QPDFTokenizer_private.hh>
@@ -556,6 +557,7 @@ class QPDF::Members
     // Document Helpers;
     std::unique_ptr<QPDFAcroFormDocumentHelper> acroform;
     std::unique_ptr<QPDFEmbeddedFileDocumentHelper> embedded_files;
+    std::unique_ptr<QPDFOutlineDocumentHelper> outlines;
     std::unique_ptr<QPDFPageLabelDocumentHelper> page_labels;
 };
@@ -597,6 +599,15 @@ QPDF::embedded_files()
     return *m->embedded_files;
 }
+inline QPDFOutlineDocumentHelper&
+QPDF::outlines()
+{
+    if (!m->outlines) {
+        m->outlines = std::make_unique<QPDFOutlineDocumentHelper>(*this);
+    }
+    return *m->outlines;
+}
+
 inline QPDFPageLabelDocumentHelper&
 QPDF::page_labels()
 {