Improvements for epee binary to hex functions:

  - Performance improvements
  - Added `span` for zero-copy pointer+length arguments
  - Added `std::ostream` overload for direct writing to output buffers
  - Removal of unused `string_tools::buff_to_hex`

1 files changed, 328 insertions, 4 deletions

diff --git a/tests/unit_tests/epee_utils.cpp b/tests/unit_tests/epee_utils.cpp
index 25b2bddd9..e8ddbe3f5 100644
--- a/tests/unit_tests/epee_utils.cpp
+++ b/tests/unit_tests/epee_utils.cpp
@@ -27,18 +27,342 @@
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #include <array>
+#include <boost/range/algorithm/equal.hpp>
+#include <boost/range/algorithm_ext/iota.hpp>
+#include <cstdint>
+#include <gtest/gtest.h>
+#include <iterator>
+#include <string>
+#include <sstream>
+#include <vector>
+
 #ifdef _WIN32
 # include <winsock.h>
 #else
 # include <arpa/inet.h>
 #endif
 
-#include <cstdint>
-#include <gtest/gtest.h>
-#include <string>
-
+#include "hex.h"
+#include "span.h"
 #include "string_tools.h"
 
+namespace
+{
+  template<typename Destination, typename Source>
+  bool can_construct()
+  {
+    const unsigned count =
+      unsigned(std::is_constructible<Destination, Source>()) +
+      unsigned(std::is_constructible<Destination, Source&>()) +
+      unsigned(std::is_convertible<Source, Destination>()) +
+      unsigned(std::is_convertible<Source&, Destination>()) +
+      unsigned(std::is_assignable<Destination, Source>()) +
+      unsigned(std::is_assignable<Destination, Source&>());
+    EXPECT_TRUE(count == 6 || count == 0) <<
+      "Mismatch on construction results - " << count << " were true";
+    return count == 6; 
+  }
+
+  // This is probably stressing the compiler more than the implementation ...
+  constexpr const epee::span<const char> test_string("a string");
+  static_assert(!test_string.empty(), "test failure");
+  static_assert(test_string.size() == 9, "test failure");
+  static_assert(test_string.size_bytes() == 9, "test_failure");
+  static_assert(test_string.begin() == test_string.cbegin(), "test failure");
+  static_assert(test_string.end() == test_string.cend(), "test failure");
+  static_assert(test_string.cend() - test_string.cbegin() == 9, "test failure");
+  static_assert(*test_string.cbegin() == 'a', "test failure");
+  static_assert(*(test_string.cend() - 2) == 'g', "test failure");
+  static_assert(
+    epee::span<const char>(test_string).cbegin() + 3 == test_string.cbegin() + 3,
+    "test failure"
+  );
+
+  static_assert(epee::span<char>().empty(), "test failure");
+  static_assert(epee::span<char>(nullptr).empty(), "test failure");
+  static_assert(epee::span<const char>("foo", 2).size() == 2, "test failure");
+
+  std::string std_to_hex(const std::vector<unsigned char>& source)
+  {
+    std::stringstream out;
+    out << std::hex;
+    for (const unsigned char byte : source)
+    {
+      out << std::setw(2) << std::setfill('0') << int(byte);
+    }
+    return out.str();
+  }
+
+  std::vector<unsigned char> get_all_bytes()
+  {
+    std::vector<unsigned char> out;
+    out.resize(256);
+    boost::range::iota(out, 0);
+    return out;
+  }
+}
+
+TEST(Span, Traits)
+{
+  EXPECT_TRUE((std::is_same<std::size_t, typename epee::span<char>::size_type>()));
+  EXPECT_TRUE((std::is_same<std::ptrdiff_t, typename epee::span<char>::difference_type>()));
+  EXPECT_TRUE((std::is_same<char, typename epee::span<char>::value_type>()));
+  EXPECT_TRUE((std::is_same<char*, typename epee::span<char>::pointer>()));
+  EXPECT_TRUE((std::is_same<const char*, typename epee::span<char>::const_pointer>()));
+  EXPECT_TRUE((std::is_same<char*, typename epee::span<char>::iterator>()));
+  EXPECT_TRUE((std::is_same<const char*, typename epee::span<char>::const_iterator>()));
+  EXPECT_TRUE((std::is_same<char&, typename epee::span<char>::reference>()));
+  EXPECT_TRUE((std::is_same<const char&, typename epee::span<char>::const_reference>()));
+
+  EXPECT_TRUE((std::is_same<std::size_t, typename epee::span<const char>::size_type>()));
+  EXPECT_TRUE((std::is_same<std::ptrdiff_t, typename epee::span<const char>::difference_type>()));
+  EXPECT_TRUE((std::is_same<const char, typename epee::span<const char>::value_type>()));
+  EXPECT_TRUE((std::is_same<const char*, typename epee::span<const char>::pointer>()));
+  EXPECT_TRUE((std::is_same<const char*, typename epee::span<const char>::const_pointer>()));
+  EXPECT_TRUE((std::is_same<const char*, typename epee::span<const char>::iterator>()));
+  EXPECT_TRUE((std::is_same<const char*, typename epee::span<const char>::const_iterator>()));
+  EXPECT_TRUE((std::is_same<const char&, typename epee::span<const char>::reference>()));
+  EXPECT_TRUE((std::is_same<const char&, typename epee::span<const char>::const_reference>()));
+}
+
+TEST(Span, MutableConstruction)
+{
+  struct no_conversion{};
+
+  EXPECT_TRUE(std::is_constructible<epee::span<char>>());
+  EXPECT_TRUE((std::is_constructible<epee::span<char>, char*, std::size_t>()));
+  EXPECT_FALSE((std::is_constructible<epee::span<char>, const char*, std::size_t>()));
+  EXPECT_FALSE((std::is_constructible<epee::span<char>, unsigned char*, std::size_t>()));
+
+  EXPECT_TRUE((can_construct<epee::span<char>, std::nullptr_t>()));
+  EXPECT_TRUE((can_construct<epee::span<char>, char(&)[1]>()));
+
+  EXPECT_FALSE((can_construct<epee::span<char>, std::vector<char>>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, std::array<char, 1>>()));
+
+  EXPECT_FALSE((can_construct<epee::span<char>, std::wstring>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, const std::vector<char>>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, std::vector<unsigned char>>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, const std::array<char, 1>>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, std::array<unsigned char, 1>>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, const char[1]>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, unsigned char[1]>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, epee::span<const char>>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, epee::span<unsigned char>>()));
+  EXPECT_FALSE((can_construct<epee::span<char>, no_conversion>()));
+}
+
+TEST(Span, ImmutableConstruction)
+{
+  struct no_conversion{};
+
+  EXPECT_TRUE(std::is_constructible<epee::span<const char>>());
+  EXPECT_TRUE((std::is_constructible<epee::span<const char>, char*, std::size_t>()));
+  EXPECT_TRUE((std::is_constructible<epee::span<const char>, const char*, std::size_t>()));
+  EXPECT_FALSE((std::is_constructible<epee::span<const char>, unsigned char*, std::size_t>()));
+
+  EXPECT_FALSE((can_construct<epee::span<const char>, std::string>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, std::vector<char>>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, const std::vector<char>>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, std::array<char, 1>>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, const std::array<char, 1>>()));
+
+  EXPECT_TRUE((can_construct<epee::span<const char>, std::nullptr_t>()));
+  EXPECT_TRUE((can_construct<epee::span<const char>, char[1]>()));
+  EXPECT_TRUE((can_construct<epee::span<const char>, const char[1]>()));
+  EXPECT_TRUE((can_construct<epee::span<const char>, epee::span<const char>>()));
+
+  EXPECT_FALSE((can_construct<epee::span<const char>, std::wstring>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, std::vector<unsigned char>>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, std::array<unsigned char, 1>>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, unsigned char[1]>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, epee::span<unsigned char>>()));
+  EXPECT_FALSE((can_construct<epee::span<const char>, no_conversion>()));
+}
+
+TEST(Span, NoExcept)
+{
+  EXPECT_TRUE(std::is_nothrow_default_constructible<epee::span<char>>());
+  EXPECT_TRUE(std::is_nothrow_move_constructible<epee::span<char>>());
+  EXPECT_TRUE(std::is_nothrow_copy_constructible<epee::span<char>>());
+  EXPECT_TRUE(std::is_move_assignable<epee::span<char>>());
+  EXPECT_TRUE(std::is_copy_assignable<epee::span<char>>());
+
+  char data[10];
+  epee::span<char> lvalue(data);
+  const epee::span<char> clvalue(data);
+  EXPECT_TRUE(noexcept(epee::span<char>()));
+  EXPECT_TRUE(noexcept(epee::span<char>(nullptr)));
+  EXPECT_TRUE(noexcept(epee::span<char>(nullptr, 0)));
+  EXPECT_TRUE(noexcept(epee::span<char>(data)));
+  EXPECT_TRUE(noexcept(epee::span<char>(lvalue)));
+  EXPECT_TRUE(noexcept(epee::span<char>(clvalue)));
+
+  // conversion from mutable to immutable not yet implemented
+  // EXPECT_TRUE(noexcept(epee::span<const char>(lvalue)));
+  // EXPECT_TRUE(noexcept(epee::span<const char>(clvalue)));
+
+  EXPECT_TRUE(noexcept(epee::span<char>(epee::span<char>(lvalue))));
+  EXPECT_TRUE(noexcept(lvalue = lvalue));
+  EXPECT_TRUE(noexcept(lvalue = clvalue));
+  EXPECT_TRUE(noexcept(lvalue = epee::span<char>(lvalue)));
+}
+
+TEST(Span, Nullptr)
+{
+  const auto check_empty = [](epee::span<const char> data)
+  {
+    EXPECT_TRUE(data.empty());
+    EXPECT_EQ(data.cbegin(), data.begin());
+    EXPECT_EQ(data.cend(), data.end());
+    EXPECT_EQ(data.cend(), data.cbegin());
+    EXPECT_EQ(0, data.size());
+    EXPECT_EQ(0, data.size_bytes());
+  };
+  check_empty({});
+  check_empty(nullptr); 
+}
+
+TEST(Span, Writing)
+{
+  const int expected[] = {-5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9};
+  std::vector<int> source;
+
+  epee::span<int> span;
+  EXPECT_TRUE(span.empty());
+  EXPECT_EQ(0, span.size());
+  EXPECT_EQ(0, span.size_bytes());
+
+  source.resize(15);
+  span = {source.data(), source.size()};
+  EXPECT_FALSE(span.empty());
+  EXPECT_EQ(15, span.size());
+  EXPECT_EQ(15 * 4, span.size_bytes());
+
+  boost::range::iota(span, -5);
+  EXPECT_EQ(span.begin(), span.cbegin());
+  EXPECT_EQ(span.end(), span.cend());
+  EXPECT_TRUE(boost::range::equal(expected, source));
+  EXPECT_TRUE(boost::range::equal(expected, span));
+}
+
+TEST(Span, ToByteSpan)
+{
+  const char expected[] = {56, 44, 11, 5};
+  EXPECT_TRUE(
+    boost::range::equal(
+      std::array<std::uint8_t, 4>{{56, 44, 11, 5}},
+      epee::to_byte_span<char>(expected)
+    )
+  );
+  EXPECT_TRUE(
+    boost::range::equal(
+      std::array<char, 4>{{56, 44, 11, 5}},
+      epee::to_byte_span(epee::span<const char>{expected})
+    )
+  );
+}
+
+TEST(Span, AsByteSpan)
+{
+  struct some_pod { char value[4]; };
+  const some_pod immutable {{ 5, 10, 12, 127 }};
+  EXPECT_TRUE(
+    boost::range::equal(
+      std::array<unsigned char, 4>{{5, 10, 12, 127}},
+      epee::as_byte_span(immutable)
+    )
+  );
+  EXPECT_TRUE(
+    boost::range::equal(
+      std::array<std::uint8_t, 3>{{'a', 'y', 0x00}}, epee::as_byte_span("ay")
+    )
+  );
+}
+
+TEST(ToHex, String)
+{
+  EXPECT_TRUE(epee::to_hex::string(nullptr).empty());
+  EXPECT_EQ(
+    std::string{"ffab0100"},
+    epee::to_hex::string(epee::as_byte_span("\xff\xab\x01"))
+  );
+
+  const std::vector<unsigned char> all_bytes = get_all_bytes();
+  EXPECT_EQ(
+    std_to_hex(all_bytes), epee::to_hex::string(epee::to_span(all_bytes))
+  );
+}
+
+TEST(ToHex, Array)
+{
+  EXPECT_EQ(
+    (std::array<char, 8>{{'f', 'f', 'a', 'b', '0', '1', '0', '0'}}),
+    (epee::to_hex::array(std::array<unsigned char, 4>{{0xFF, 0xAB, 0x01, 0x00}}))
+  );
+}
+
+TEST(ToHex, Ostream)
+{
+  std::stringstream out;
+  epee::to_hex::buffer(out, nullptr);
+  EXPECT_TRUE(out.str().empty());
+
+  {
+    const std::uint8_t source[] = {0xff, 0xab, 0x01, 0x00};
+    epee::to_hex::buffer(out, source);
+  }
+
+  std::string expected{"ffab0100"};
+  EXPECT_EQ(expected, out.str());
+
+  const std::vector<unsigned char> all_bytes = get_all_bytes();
+
+  expected.append(std_to_hex(all_bytes));
+  epee::to_hex::buffer(out, epee::to_span(all_bytes));
+  EXPECT_EQ(expected, out.str());
+}
+
+TEST(ToHex, Formatted)
+{
+  std::stringstream out;
+  std::string expected{"<>"};
+
+  epee::to_hex::formatted(out, nullptr);
+  EXPECT_EQ(expected, out.str());
+
+  expected.append("<ffab0100>");
+  epee::to_hex::formatted(out, epee::as_byte_span("\xFF\xAB\x01"));
+  EXPECT_EQ(expected, out.str());
+
+  const std::vector<unsigned char> all_bytes = get_all_bytes();
+
+  expected.append("<").append(std_to_hex(all_bytes)).append(">");
+  epee::to_hex::formatted(out, epee::to_span(all_bytes));
+  EXPECT_EQ(expected, out.str());
+}
+
+TEST(StringTools, BuffToHex)
+{
+  const std::vector<unsigned char> all_bytes = get_all_bytes();
+
+  EXPECT_EQ(
+    std_to_hex(all_bytes),
+    (epee::string_tools::buff_to_hex_nodelimer(
+      std::string{reinterpret_cast<const char*>(all_bytes.data()), all_bytes.size()}
+    ))
+  );
+}
+
+TEST(StringTools, PodToHex)
+{
+  struct some_pod { unsigned char data[4]; };
+  EXPECT_EQ(
+    std::string{"ffab0100"},
+    (epee::string_tools::pod_to_hex(some_pod{{0xFF, 0xAB, 0x01, 0x00}}))
+  );
+}
+
 TEST(StringTools, GetIpString)
 {
   EXPECT_EQ(