From 07ec748c8245b42de0ec9964b2f0062c0034f2f8 Mon Sep 17 00:00:00 2001
From: moneromooo-monero <moneromooo-monero@users.noreply.github.com>
Date: Mon, 27 Aug 2018 08:43:56 +0000
Subject: [PATCH] wipeable_string: add hex_to_pod function

---
 contrib/epee/include/hex.h             |  1 +
 contrib/epee/include/wipeable_string.h | 19 ++++++++++++++++++-
 contrib/epee/src/wipeable_string.cpp   |  3 ++-
 tests/unit_tests/wipeable_string.cpp   |  7 +++++++
 4 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/contrib/epee/include/hex.h b/contrib/epee/include/hex.h
index 02600c320..901c666a9 100644
--- a/contrib/epee/include/hex.h
+++ b/contrib/epee/include/hex.h
@@ -44,6 +44,7 @@ namespace epee
     static std::string string(const span<const std::uint8_t> src);
     //! \return A epee::wipeable_string containing hex of `src`.
     static epee::wipeable_string wipeable_string(const span<const std::uint8_t> src);
+    template<typename T> static epee::wipeable_string wipeable_string(const T &pod) { return wipeable_string(span<const uint8_t>((const uint8_t*)&pod, sizeof(pod))); }
 
     //! \return An array containing hex of `src`.
     template<std::size_t N>
diff --git a/contrib/epee/include/wipeable_string.h b/contrib/epee/include/wipeable_string.h
index 4cebe5fdf..31854fe2e 100644
--- a/contrib/epee/include/wipeable_string.h
+++ b/contrib/epee/include/wipeable_string.h
@@ -28,10 +28,11 @@
 
 #pragma once
 
-#include <boost/optional/optional_fwd.hpp>
+#include <boost/optional/optional.hpp>
 #include <stddef.h>
 #include <vector>
 #include <string>
+#include "memwipe.h"
 #include "fnv1.h"
 
 namespace epee
@@ -65,6 +66,8 @@ namespace epee
     void trim();
     void split(std::vector<wipeable_string> &fields) const;
     boost::optional<wipeable_string> parse_hexstr() const;
+    template<typename T> inline bool hex_to_pod(T &pod) const;
+    template<typename T> inline bool hex_to_pod(tools::scrubbed<T> &pod) const { return hex_to_pod(unwrap(pod)); }
     void resize(size_t sz);
     void reserve(size_t sz);
     void clear();
@@ -79,6 +82,20 @@ namespace epee
   private:
     std::vector<char> buffer;
   };
+
+  template<typename T> inline bool wipeable_string::hex_to_pod(T &pod) const
+  {
+    static_assert(std::is_pod<T>::value, "expected pod type");
+    if (size() != sizeof(T) * 2)
+      return false;
+    boost::optional<epee::wipeable_string> blob = parse_hexstr();
+    if (!blob)
+      return false;
+    if (blob->size() != sizeof(T))
+      return false;
+    pod = *(const T*)blob->data();
+    return true;
+  }
 }
 
 namespace std
diff --git a/contrib/epee/src/wipeable_string.cpp b/contrib/epee/src/wipeable_string.cpp
index 7c9722765..69f92e106 100644
--- a/contrib/epee/src/wipeable_string.cpp
+++ b/contrib/epee/src/wipeable_string.cpp
@@ -32,6 +32,8 @@
 #include "misc_log_ex.h"
 #include "wipeable_string.h"
 
+static constexpr const char hex[] = u8"0123456789abcdef";
+
 namespace
 {
   int atolower(int c)
@@ -197,7 +199,6 @@ boost::optional<epee::wipeable_string> wipeable_string::parse_hexstr() const
   const size_t len = size();
   const char *d = data();
   res->grow(0, len / 2);
-  static constexpr const char hex[] = u8"0123456789abcdef";
   for (size_t i = 0; i < len; i += 2)
   {
     char c = atolower(d[i]);
diff --git a/tests/unit_tests/wipeable_string.cpp b/tests/unit_tests/wipeable_string.cpp
index 5ea1c1729..65718fd45 100644
--- a/tests/unit_tests/wipeable_string.cpp
+++ b/tests/unit_tests/wipeable_string.cpp
@@ -32,6 +32,7 @@
 
 #include "misc_log_ex.h"
 #include "wipeable_string.h"
+#include "hex.h"
 
 TEST(wipeable_string, ctor)
 {
@@ -202,3 +203,9 @@ TEST(wipeable_string, parse_hexstr)
   ASSERT_TRUE((s = epee::wipeable_string("414243").parse_hexstr()));
   ASSERT_EQ(*s, epee::wipeable_string("ABC"));
 }
+
+TEST(wipeable_string, to_hex)
+{
+  ASSERT_TRUE(epee::to_hex::wipeable_string(epee::span<const uint8_t>((const uint8_t*)"", 0)) == epee::wipeable_string(""));
+  ASSERT_TRUE(epee::to_hex::wipeable_string(epee::span<const uint8_t>((const uint8_t*)"abc", 3)) == epee::wipeable_string("616263"));
+}