Merge pull request #13727 from JoshuaVandaele/fmt-11.2.0-localtime-deprec

fmt: Replace deprecated `fmt::localtime` usage with `Common::LocalTime`

Source/Core/Common/FatFsUtil.cpp

@@ -25,6 +25,7 @@
 #include "Common/Logging/Log.h"
 #include "Common/ScopeGuard.h"
 #include "Common/StringUtil.h"
+#include "Common/TimeUtil.h"
 
 #include "Core/Config/MainSettings.h"
 
@@ -95,12 +96,7 @@ int SDCardDiskIOCtl(File::IOFile* image, u8 pdrv, u8 cmd, void* buff)
 u32 GetSystemTimeFAT()
 {
   const std::time_t time = std::time(nullptr);
-  std::tm tm;
-#ifdef _WIN32
-  localtime_s(&tm, &time);
-#else
-  localtime_r(&time, &tm);
-#endif
+  std::tm tm = *Common::LocalTime(time);
 
   DWORD fattime = 0;
   fattime |= (tm.tm_year - 80) << 25;

Source/Core/Common/SettingsHandler.cpp

@@ -122,7 +122,6 @@ std::string SettingsWriter::GenerateSerialNumber()
 
   // Must be 9 characters at most; otherwise the serial number will be rejected by SDK libraries,
   // as there is a check to ensure the string length is strictly lower than 10.
-  // 3 for %j, 2 for %H, 2 for %M, 2 for %S.
-  return fmt::format("{:%j%H%M%S}", fmt::localtime(t));
+  return fmt::format("{:09}", t % 1000000000);
 }
 }  // namespace Common

Source/Core/Common/TimeUtil.cpp

@@ -2,23 +2,25 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include "Common/TimeUtil.h"
+#include "Common/Logging/Log.h"
 
 #include <ctime>
 #include <optional>
 
 namespace Common
 {
-std::optional<std::tm> Localtime(std::time_t time)
+std::optional<std::tm> LocalTime(std::time_t time)
 {
   std::tm local_time;
 #ifdef _MSC_VER
   if (localtime_s(&local_time, &time) != 0)
-    return std::nullopt;
 #else
-  std::tm* result = localtime_r(&time, &local_time);
-  if (result != &local_time)
-    return std::nullopt;
+  if (localtime_r(&time, &local_time) == NULL)
 #endif
+  {
+    ERROR_LOG_FMT(COMMON, "Failed to convert time to local time: {}", std::strerror(errno));
+    return std::nullopt;
+  }
   return local_time;
 }
 }  // Namespace Common

Source/Core/Common/TimeUtil.h

@@ -9,5 +9,5 @@
 namespace Common
 {
 // Threadsafe and error-checking variant of std::localtime()
-std::optional<std::tm> Localtime(std::time_t time);
+std::optional<std::tm> LocalTime(std::time_t time);
 }  // Namespace Common