Add read write functions for some std containers.

1 files changed, 46 insertions, 0 deletions

diff --git a/coding/read_write_utils.hpp b/coding/read_write_utils.hpp
new file mode 100644
index 0000000000..fb961834f2
--- /dev/null
+++ b/coding/read_write_utils.hpp
@@ -0,0 +1,46 @@
+#pragma once
+
+#include "varint.hpp"
+
+#include "../std/string.hpp"
+#include "../std/vector.hpp"
+
+
+namespace rw
+{
+  template <class TSink>
+  void Write(TSink & sink, string const & s)
+  {
+    uint32_t const count = static_cast<uint32_t>(s.size());
+    WriteVarUint(sink, count);
+    if (!s.empty())
+      sink.Write(&s[0], count);
+  }
+
+  template <class TSource>
+  void Read(TSource & src, string & s)
+  {
+    uint32_t const count = ReadVarUint<uint32_t>(src);
+    s.resize(count);
+    if (count > 0)
+      src.Read(&s[0], count);
+  }
+
+  template <class TSink, class T>
+  void Write(TSink & sink, vector<T> const & v)
+  {
+    uint32_t const count = static_cast<uint32_t>(v.size());
+    WriteVarUint(sink, count);
+    for (uint32_t i = 0; i < count; ++i)
+      Write(sink, v[i]);
+  }
+
+  template <class TSource, class T>
+  void Read(TSource & src, vector<T> & v)
+  {
+    uint32_t const count = ReadVarUint<uint32_t>(src);
+    v.resize(count);
+    for (size_t i = 0; i < count; ++i)
+      Read(src, v[i]);
+  }
+}