update to c++20

With various associated library updates and compatibility fixes.

Author: jagerman

CMakeLists.txt

@@ -15,7 +15,7 @@ endif()
 
 project(spns)
 
-set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
 set(CMAKE_POSITION_INDEPENDENT_CODE ON)

libpqxx

@@ -47,6 +47,9 @@ struct is_bytes_impl {
 template <typename T>
 inline constexpr bool is_bytes = decltype(is_bytes_impl::check(static_cast<T*>(nullptr)))::value;
 
+template <typename T>
+concept bytes_subtype = is_bytes<T>;
+
 struct AccountID : bytes<33> {};
 struct Ed25519PK : bytes<32> {};
 struct X25519PK : bytes<32> {};

oxen-logging

@@ -912,8 +912,9 @@ void HiveMind::log_stats(std::string_view pre_cmd) {
             total_notifies,
             pushes_processed_.load());
 
-    auto sd_format = pre_cmd.empty() ? "STATUS={1}" : "{0}\nSTATUS={1}";
-    sd_notify(0, fmt::format(sd_format, pre_cmd, stat_line).c_str());
+    auto sd_out = pre_cmd.empty() ? "STATUS={}"_format(stat_line)
+                                  : "{}\nSTATUS={}"_format(pre_cmd, stat_line);
+    sd_notify(0, sd_out.c_str());
 
     if (auto now = std::chrono::steady_clock::now(); now - last_stats_logged >= 4min + 55s) {
         log::info(stats, "Status: {}", stat_line);
@@ -1049,12 +1050,7 @@ void HiveMind::on_notifier_validation(
         response["message"] = std::move(message);
 
     sub_json_set_one_response(
-        std::move(replier),
-        final_response,
-        i,
-        remaining,
-        multi,
-        std::move(response));
+            std::move(replier), final_response, i, remaining, multi, std::move(response));
 }
 
 std::tuple<SwarmPubkey, std::optional<Subaccount>, int64_t, Signature, std::string, nlohmann::json>
@@ -1667,8 +1663,8 @@ SELECT
     ARRAY(SELECT namespace FROM sub_namespaces WHERE subscription = id ORDER BY namespace)
 FROM subscriptions
 WHERE
-    account = {} AND service = {} AND svcid = {})"_format(
-                    tx.quote(pubkey.id), tx.quote(service), tx.quote(service_id)));
+    account = $1 AND service = $2 AND svcid = $3)",
+            {pubkey.id, service, service_id});
     int64_t id;
     if (result) {
         auto& [row_id, sig_ts, ns_arr] = *result;

spns/bytes.hpp

@@ -1,7 +1,9 @@
+#pragma once
+
 #include <chrono>
 #include <mutex>
 #include <pqxx/pqxx>
-#include <stack>
+#include <deque>
 
 #include "bytes.hpp"
 
@@ -117,7 +119,7 @@ inline const std::string type_name<spns::Signature>{"spns::Signature"};
 template <>
 inline const std::string type_name<spns::EncKey>{"spns::EncKey"};
 
-template <typename T, typename = std::enable_if_t<spns::is_bytes<T>>>
+template <spns::bytes_subtype T>
 struct spns_byte_helper {
     static constexpr size_t SIZE = T::SIZE;
     static T from_string(std::string_view text) {
@@ -148,9 +150,6 @@ struct spns_byte_helper {
     }
 };
 
-template <typename T>
-struct nullness<T, std::enable_if_t<spns::is_bytes<T>>> : pqxx::no_null<T> {};
-
 template <>
 struct string_traits<spns::AccountID> : spns_byte_helper<spns::AccountID> {};
 template <>

spns/hivemind.cpp

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <fmt/format.h>
+#include <oxen/log/format.hpp>
 
 #include <charconv>
 #include <chrono>
@@ -40,37 +41,7 @@ inline ustring_view as_usv(bstring_view s) {
     return {reinterpret_cast<const unsigned char*>(s.data()), s.size()};
 }
 
-// Can replace this with a `using namespace oxen::log::literals` if we start using oxen-logging
-namespace detail {
-
-    // Internal implementation of _format that holds the format temporarily until the (...) operator
-    // is invoked on it.  This object cannot be moved, copied but only used ephemerally in-place.
-    struct fmt_wrapper {
-      private:
-        std::string_view format;
-
-        // Non-copyable and non-movable:
-        fmt_wrapper(const fmt_wrapper&) = delete;
-        fmt_wrapper& operator=(const fmt_wrapper&) = delete;
-        fmt_wrapper(fmt_wrapper&&) = delete;
-        fmt_wrapper& operator=(fmt_wrapper&&) = delete;
-
-      public:
-        constexpr explicit fmt_wrapper(const char* str, const std::size_t len) : format{str, len} {}
-
-        /// Calling on this object forwards all the values to fmt::format, using the format string
-        /// as provided during construction (via the "..."_format user-defined function).
-        template <typename... T>
-        auto operator()(T&&... args) && {
-            return fmt::format(format, std::forward<T>(args)...);
-        }
-    };
-
-}  // namespace detail
-
-inline detail::fmt_wrapper operator""_format(const char* str, size_t len) {
-    return detail::fmt_wrapper{str, len};
-}
+using namespace oxen::log::literals;
 
 /// Splits a string on some delimiter string and returns a vector of string_view's pointing into the
 /// pieces of the original string.  The pieces are valid only as long as the original string remains