1 files changed, 62 insertions, 0 deletions
diff --git a/test/interactive-helper/teestream.h b/test/interactive-helper/teestream.h
new file mode 100644
index 0000000..058717a
--- /dev/null
+++ b/test/interactive-helper/teestream.h
@@ -0,0 +1,62 @@
+#ifndef APT_HELPER_TEESTREAM_H
+#define APT_HELPER_TEESTREAM_H
+
+/* 'basic' implementation of a streambuf which passes the output
+   to two 'real' streambufs emulating '| tee' on the shell
+
+   The main use is streaming debug output to std::clog as well as
+   a logfile easily, so don't expect that to be a bulletproof
+   implementation. */
+
+#include <apt-pkg/macros.h>
+#include <iostream>
+
+template <typename CharT, typename Traits = std::char_traits<CharT>
+> class basic_teebuf: public std::basic_streambuf<CharT, Traits>
+{
+public:
+   basic_teebuf(std::basic_streambuf<CharT, Traits> * const sb1,
+	 std::basic_streambuf<CharT, Traits> * const sb2)
+      : s1(sb1), s2(sb2) {}
+protected:
+   virtual std::streamsize xsputn(const CharT* s, std::streamsize c) APT_OVERRIDE
+   {
+      return s2->sputn(s, s1->sputn(s, c));
+   }
+   // overflow is the fallback of sputc which is non-virtual
+   typedef typename Traits::int_type int_type;
+   virtual int_type overflow(int_type ch = Traits::eof()) APT_OVERRIDE
+   {
+      auto const eof = Traits::eof();
+      if (Traits::eq_int_type(ch, Traits::eof()) == true)
+	 return eof;
+
+      auto const r1 = s1->sputc(Traits::to_char_type(ch));
+      auto const r2 = s2->sputc(Traits::to_char_type(ch));
+      return Traits::eq_int_type(r1, eof) ? r1: r2;
+   }
+   virtual void imbue(const std::locale& loc) APT_OVERRIDE
+   {
+      s1->pubimbue(loc);
+      s2->pubimbue(loc);
+   }
+   virtual int sync() APT_OVERRIDE
+   {
+      auto const r1 = s1->pubsync();
+      auto const r2 = s2->pubsync();
+      return r1 == 0 ? r2 : r1;
+   }
+private:
+   std::basic_streambuf<CharT, Traits> * const s1;
+   std::basic_streambuf<CharT, Traits> * const s2;
+};
+template <typename CharT, typename Traits = std::char_traits<CharT>
+> class basic_teeostream: public std::basic_ostream<CharT, Traits>
+{
+public:
+    basic_teeostream(std::basic_ostream<CharT, Traits> &o1, std::basic_ostream<CharT, Traits> &o2) :
+       std::basic_ostream<CharT, Traits>(&tbuf), tbuf(o1.rdbuf(), o2.rdbuf()) {}
+private:
+    basic_teebuf<CharT, Traits> tbuf;
+};
+#endif