From f37311a3f1652eda11f67f408e586a780b269efe Mon Sep 17 00:00:00 2001
From: Jason Volk <jason@zemos.net>
Date: Thu, 21 Dec 2017 14:25:50 -0700
Subject: [PATCH] ircd::util: Add an endian bswap; add more data()/size()
 participants.

---
 include/ircd/util.h | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/include/ircd/util.h b/include/ircd/util.h
index afc14fb79..c67c4f1c7 100644
--- a/include/ircd/util.h
+++ b/include/ircd/util.h
@@ -404,6 +404,13 @@ size(const std::array<char, SIZE> &buf)
 	return SIZE;
 }
 
+template<class T>
+constexpr typename std::enable_if<std::is_pod<T>::value, size_t>::type
+size(const T &val)
+{
+	return sizeof(T);
+}
+
 
 template<size_t SIZE>
 constexpr const char *
@@ -419,6 +426,20 @@ data(char (&buf)[SIZE])
 	return buf;
 }
 
+template<class T>
+constexpr typename std::enable_if<std::is_pod<T>::value, const uint8_t *>::type
+data(const T &val)
+{
+	return reinterpret_cast<const uint8_t *>(&val);
+}
+
+template<class T>
+constexpr typename std::enable_if<std::is_pod<T>::value, uint8_t *>::type
+data(T &val)
+{
+	return reinterpret_cast<uint8_t *>(&val);
+}
+
 
 template<class T>
 auto
@@ -1044,5 +1065,24 @@ is_powerof2(const long long v)
 }
 
 
+template<class T>
+T &
+bswap(T *const &val)
+{
+	assert(val != nullptr);
+	std::reverse(data(*val), data(*val) + size(*val));
+	return *val;
+}
+
+template<class T>
+T
+bswap(const T &val)
+{
+	T ret;
+	std::reverse_copy(data(val), data(val) + size(val), data(ret));
+	return ret;
+}
+
+
 } // namespace util
 } // namespace ircd