More work on client and server

luprex/core/cpp/printbuffer.hpp

@@ -71,9 +71,11 @@
 
 #include "streambuffer.hpp"
 #include "util.hpp"
+#include "invocation.hpp"
 #include <deque>
 #include <string>
 #include <memory>
+#include <ostream>
 
 class PrintBuffer {
 private:
@@ -136,5 +138,25 @@ public:
 
 using UniquePrintBuffer = std::unique_ptr<PrintBuffer>;
 
+class PrintChanneler {
+private:
+    int64_t line_;
+public:
+    PrintChanneler() { line_ = 0; }
+
+    // Reset the print channeler.
+    void reset() { line_ = 0; }
+    
+    // Copy any new lines from the printbuffer to the stdostream.
+    // Update the current line number.  Return true if the printbuffer
+    // contains any lines that have already been channeled.
+    bool channel(const PrintBuffer *pb, std::ostream &ostream);
+
+    // Generate an invocation that removes unnecessary lines from the
+    // printbuffer.
+    Invocation invocation(int64_t actor_id);
+};
+
+
 #endif // PRINTBUFFER_HPP