From 2901943618f071060f72d69cf632a4097e439df4 Mon Sep 17 00:00:00 2001
From: Kefu Chai <tchaikov@gmail.com>
Date: Sat, 27 Aug 2022 11:00:20 +0800
Subject: [PATCH] common/LogEntry: specialize fmt::formatter<LogEntry>

so we can use the formatter defined for `LogEntry` in fmtlib v9.
in this new version of fmtlib, it is required to define a specialization
for the formatted type even when it comes to the types with an override of
operator<<(). since we already have an override for `LogEntry`, let's define
the specialization for `fmt::formatter<LogEntry>`.

this change should address the FTBFS when building with fmtlib v9.

Signed-off-by: Kefu Chai <tchaikov@gmail.com>
---
 src/common/LogEntry.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/common/LogEntry.h b/src/common/LogEntry.h
index 124a207992070..3ddebbd3043c0 100644
--- a/src/common/LogEntry.h
+++ b/src/common/LogEntry.h
@@ -15,7 +15,10 @@
 #ifndef CEPH_LOGENTRY_H
 #define CEPH_LOGENTRY_H
 
+#include <fmt/format.h>
+
 #include "include/utime.h"
+#include "msg/msg_fmt.h"
 #include "msg/msg_types.h"
 #include "common/entity_name.h"
 #include "ostream_temp.h"
@@ -191,4 +194,19 @@ inline std::ostream& operator<<(std::ostream& out, const LogEntry& e)
              << e.channel << " " << e.prio << " " << e.msg;
 }
 
+template <> struct fmt::formatter<EntityName> : fmt::formatter<std::string_view> {
+  template <typename FormatContext>
+  auto format(const EntityName& e, FormatContext& ctx) {
+    return formatter<std::string_view>::format(e.to_str(), ctx);
+  }
+};
+
+template <> struct fmt::formatter<LogEntry> : fmt::formatter<std::string_view> {
+  template <typename FormatContext>
+  auto format(const LogEntry& e, FormatContext& ctx) {
+    return fmt::format_to(ctx.out(), "{} {} ({}) {} : {} {} {}",
+			  e.stamp, e.name, e.rank, e.seq, e.channel, e.prio, e.msg);
+  }
+};
+
 #endif
-- 
2.39.5