Enhance pl::Count to incorporate an end-of-line Pl_String

m-holger
1 parent 876c238e
Showing 3 changed files with 27 additions and 11 deletions
include/qpdf/QPDFWriter.hh
libqpdf/QPDFWriter.cc
libqpdf/qpdf/Pipeline_private.hh
@@ -597,12 +597,14 @@ class QPDFWriter
     // activate the pipeline stack. When the passed in PipelinePopper goes out of scope, the stack
     // is popped.
     Pipeline* pushPipeline(Pipeline*);
-    void activatePipelineStack(PipelinePopper& pp, bool discard = false);
+    void
+    activatePipelineStack(PipelinePopper& pp, bool discard = false, std::string* str = nullptr);
     void initializePipelineStack(Pipeline*);
  
     void adjustAESStreamLength(size_t& length);
     void pushEncryptionFilter(PipelinePopper&);
     void pushDiscardFilter(PipelinePopper&);
+    void pushStringPipeline(PipelinePopper&, std::string& str);
     void pushMD5Pipeline(PipelinePopper&);
     void computeDeterministicIDData();
  
@@ -917,10 +917,11 @@ QPDFWriter::initializePipelineStack(Pipeline* p)
 }
  
 void
-QPDFWriter::activatePipelineStack(PipelinePopper& pp, bool discard)
+QPDFWriter::activatePipelineStack(PipelinePopper& pp, bool discard, std::string* str)
 {
     std::string stack_id("stack " + std::to_string(m->next_stack_id));
-    auto* c = new pl::Count(stack_id.c_str(), discard ? nullptr : m->pipeline_stack.back());
+    auto* c = str ? new pl::Count(stack_id.c_str(), str)
+                  : new pl::Count(stack_id.c_str(), discard ? nullptr : m->pipeline_stack.back());
     ++m->next_stack_id;
     m->pipeline_stack.emplace_back(c);
     m->pipeline = c;
@@ -996,6 +997,12 @@ QPDFWriter::pushDiscardFilter(PipelinePopper&amp; pp)
 }
  
 void
+QPDFWriter::pushStringPipeline(PipelinePopper& pp, std::string& str)
+{
+    activatePipelineStack(pp, true, &str);
+}
+
+void
 QPDFWriter::pushMD5Pipeline(PipelinePopper& pp)
 {
     if (!m->id2.empty()) {
@@ -1280,8 +1287,7 @@ QPDFWriter::willFilterStream(
     for (bool first_attempt: {true, false}) {
         PipelinePopper pp_stream_data(this);
         if (stream_data != nullptr) {
-            pushPipeline(new Pl_String("stream data", nullptr, *stream_data));
-            activatePipelineStack(pp_stream_data);
+            pushStringPipeline(pp_stream_data, *stream_data);
         } else {
             pushDiscardFilter(pp_stream_data);
         }
@@ -1644,9 +1650,7 @@ QPDFWriter::writeObjectStream(QPDFObjectHandle object)
     {
         // Pass 1
         PipelinePopper pp_ostream_pass1(this);
-
-        pushPipeline(new Pl_String("object stream", nullptr, stream_buffer_pass1));
-        activatePipelineStack(pp_ostream_pass1);
+        pushStringPipeline(pp_ostream_pass1, stream_buffer_pass1);
  
         int count = -1;
         for (auto const& obj: m->object_stream_to_objects[old_id]) {
@@ -2888,9 +2892,8 @@ QPDFWriter::writeLinearized()
  
             // Write hint stream to a buffer
             {
-                pushPipeline(new Pl_String("hint buffer", nullptr, hint_buffer));
                 PipelinePopper pp_hint(this);
-                activatePipelineStack(pp_hint);
+                pushStringPipeline(pp_hint, hint_buffer);
                 writeHintStream(hint_id);
             }
             hint_length = QIntC::to_offset(hint_buffer.size());
@@ -13,12 +13,22 @@ namespace qpdf::pl
         {
         }
  
+        Count(char const* identifier, std::string* str) :
+            Pipeline(identifier, nullptr),
+            str(str)
+        {
+        }
+
         ~Count() final = default;
  
         void
         write(unsigned char const* buf, size_t len) final
         {
             if (len) {
+                if (str) {
+                    str->append(reinterpret_cast<char const*>(buf), len);
+                    return;
+                }
                 count += static_cast<qpdf_offset_t>(len);
                 if (next()) {
                     next()->write(buf, len);
@@ -37,11 +47,12 @@ namespace qpdf::pl
         qpdf_offset_t
         getCount() const
         {
-            return count;
+            return str ? static_cast<qpdf_offset_t>(str->size()) : count;
         }
  
       private:
         qpdf_offset_t count{0};
+        std::string* str{nullptr};
     };
 } // namespace qpdf::pl