LogManager: Use colors for logging when possible

FEXCore/include/FEXCore/Utils/LogManager.h

@@ -6,6 +6,7 @@
 #include <cstdarg>
 
 #include <fmt/format.h>
+#include <fmt/color.h>
 
 namespace LogMan {
 enum DebugLevels {
@@ -31,6 +32,16 @@ static inline const char* DebugLevelStr(uint32_t Level) {
   }
 }
 
+static inline fmt::text_style DebugLevelStyle(uint32_t Level) {
+  switch (Level) {
+  case LogMan::ASSERT: return fmt::bg(fmt::color::red) | fmt::emphasis::bold | fmt::fg(fmt::color::white);
+  case LogMan::ERROR: return fmt::fg(fmt::color::red);
+  case LogMan::DEBUG: return fmt::fg(fmt::color::gray);
+  case LogMan::INFO: return fmt::fg(fmt::color::green);
+  default: return {}; break;
+  }
+}
+
 constexpr DebugLevels MSG_LEVEL = INFO;
 
 // Note that all logging functions with the Fmt or _FMT suffix on them expect

Source/Tools/FEXLoader/FEXLoader.cpp

@@ -68,24 +68,22 @@ namespace {
 static bool SilentLog {};
 static int OutputFD {STDERR_FILENO};
 
+// Set an empty style to disable coloring when FEXServer output is e.g. piped to a file
+static bool DisableOutputColors {};
+
 void MsgHandler(LogMan::DebugLevels Level, const char* Message) {
   if (SilentLog) {
     return;
   }
 
-  const auto Output = fextl::fmt::format("[{}] {}\n", LogMan::DebugLevelStr(Level), Message);
+  const auto Style = DisableOutputColors ? fmt::text_style {} : LogMan::DebugLevelStyle(Level);
+  const auto Output = fextl::fmt::format("{} {}\n", fmt::styled(LogMan::DebugLevelStr(Level), Style), Message);
   write(OutputFD, Output.c_str(), Output.size());
   fsync(OutputFD);
 }
 
 void AssertHandler(const char* Message) {
-  if (SilentLog) {
-    return;
-  }
-
-  const auto Output = fextl::fmt::format("[ASSERT] {}\n", Message);
-  write(OutputFD, Output.c_str(), Output.size());
-  fsync(OutputFD);
+  return MsgHandler(LogMan::ASSERT, Message);
 }
 
 } // Anonymous namespace
@@ -383,6 +381,7 @@ int main(int argc, char** argv, char** const envp) {
       OutputFD = open(LogFile.c_str(), O_CREAT | O_CLOEXEC | O_WRONLY, USER_PERMS);
     }
   }
+  DisableOutputColors = !isatty(OutputFD);
 
   if (StartupSleep() && (StartupSleepProcName().empty() || Program.ProgramName == StartupSleepProcName())) {
     LogMan::Msg::IFmt("[{}][{}] Sleeping for {} seconds", ::getpid(), Program.ProgramName, StartupSleep());

Source/Tools/FEXServer/Main.cpp

@@ -9,6 +9,8 @@
 #include "Common/Config.h"
 #include "Common/FEXServerClient.h"
 
+#include <fmt/color.h>
+
 #include <chrono>
 #include <dirent.h>
 #include <fcntl.h>
@@ -23,20 +25,23 @@
 #include <sys/types.h>
 #include <sys/un.h>
 #include <sys/wait.h>
+#include <termios.h>
 #include <thread>
 #include <unistd.h>
 
 static timespec StartTime {};
 
+// Set an empty style to disable coloring when FEXServer output is e.g. piped to a file
+static std::optional<fmt::text_style> DisableColors = isatty(STDOUT_FILENO) ? std::nullopt : std::optional {fmt::text_style {}};
+
 namespace Logging {
 void MsgHandler(LogMan::DebugLevels Level, const char* Message) {
-  const auto Output = fmt::format("[{}] {}\n", LogMan::DebugLevelStr(Level), Message);
+  const auto Output = fmt::format("{} {}\n", fmt::styled(LogMan::DebugLevelStr(Level), DisableColors.value_or(DebugLevelStyle(Level))), Message);
   write(STDOUT_FILENO, Output.c_str(), Output.size());
 }
 
 void AssertHandler(const char* Message) {
-  const auto Output = fmt::format("[A] {}\n", Message);
-  write(STDOUT_FILENO, Output.c_str(), Output.size());
+  return MsgHandler(LogMan::ASSERT, Message);
 }
 
 void ClientMsgHandler(int FD, FEXServerClient::Logging::PacketMsg* const Msg, const char* MsgStr) {
@@ -45,8 +50,13 @@ void ClientMsgHandler(int FD, FEXServerClient::Logging::PacketMsg* const Msg, co
   }
   auto seconds = Msg->Header.Timestamp.tv_sec - StartTime.tv_sec - (Msg->Header.Timestamp.tv_nsec < StartTime.tv_nsec);
   auto nanos = (1'000'000'000 + Msg->Header.Timestamp.tv_nsec - StartTime.tv_nsec) % 1'000'000'000;
-  const auto Output = fmt::format("[{}][{}.{:03}][{}|{}] {}\n", LogMan::DebugLevelStr(Msg->Level), Msg->Header.Timestamp.tv_sec,
-                                  Msg->Header.Timestamp.tv_nsec, Msg->Header.PID, Msg->Header.TID, MsgStr);
+  char Metadata[128];
+  auto Cursor =
+    fmt::format_to(&Metadata[0], DisableColors.value_or(LogMan::DebugLevelStyle(Msg->Level)), "{}", LogMan::DebugLevelStr(Msg->Level));
+  Cursor = fmt::format_to(Cursor, DisableColors.value_or(fmt::fg(fmt::color::light_gray)), " {}|{} ", Msg->Header.PID, Msg->Header.TID);
+  Cursor = fmt::format_to(Cursor, DisableColors.value_or(fmt::fg(fmt::color::gray)), "{}.{:03}", seconds, nanos / 1000000);
+  *Cursor = 0;
+  auto Output = fmt::format("{} {}\n", Metadata, MsgStr);
   write(STDERR_FILENO, Output.c_str(), Output.size());
 }
 } // namespace Logging