From 639b28700402fa3335f5b694a2b450eb13775c75 Mon Sep 17 00:00:00 2001
From: David Rohr <drohr@jwdt.org>
Date: Wed, 17 Jun 2020 14:21:40 +0200
Subject: [PATCH] Suppress LOG messages with debug severity or less at compile
 time for release builds

---
 logger/Logger.h | 62 +++++++++++++++++++++++++++++++------------------
 1 file changed, 40 insertions(+), 22 deletions(-)

diff --git a/logger/Logger.h b/logger/Logger.h
index 5f8ae9c..b69c763 100644
--- a/logger/Logger.h
+++ b/logger/Logger.h
@@ -13,6 +13,10 @@
 #warning "The symbol 'DEBUG' is used in FairRoot Logger. undefining..."
 #endif
 
+#if !defined(FAIR_MIN_SEVERITY) && defined(NDEBUG)
+#define FAIR_MIN_SEVERITY info
+#endif
+
 #ifdef FAIRLOGGER_USE_BOOST_PRETTY_FUNCTION
 #include <boost/current_function.hpp>
 #endif
@@ -46,18 +50,18 @@ namespace fair
 
 enum class Severity : int
 {
-    nolog,
-    fatal,
-    error,
-    warn,
-    state,
-    info,
-    debug,
-    debug1,
-    debug2,
-    debug3,
-    debug4,
-    trace,
+    nolog = 0,
+    fatal = 11,
+    error = 10,
+    warn = 9,
+    state = 8,
+    info = 7,
+    debug = 6,
+    debug1 = 5,
+    debug2 = 4,
+    debug3 = 3,
+    debug4 = 2,
+    trace = 1,
     // backwards-compatibility:
     NOLOG = nolog,
     FATAL = fatal,
@@ -313,6 +317,15 @@ class Logger
     static bool fIsDestructed;
     static struct DestructionHelper { ~DestructionHelper() { Logger::fIsDestructed = true; }} fDestructionHelper;
 
+    static bool constexpr SuppressSeverity(Severity sev)
+    {
+#ifdef FAIR_MIN_SEVERITY
+        return sev < Severity::FAIR_MIN_SEVERITY;
+#else
+        return false;
+#endif
+    }
+
   private:
     LogMetaData fInfos;
 
@@ -394,13 +407,15 @@ class Logger
 
 // Log line if the provided severity is below or equals the configured one
 #define FAIR_LOG(severity) \
-    for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(fair::Severity::severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
-        fair::Logger(fair::Severity::severity, MSG_ORIGIN)
+    if (fair::Logger::SuppressSeverity(fair::Severity::severity)) ; else \
+        for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(fair::Severity::severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
+            fair::Logger(fair::Severity::severity, MSG_ORIGIN)
 
 // Log line with the given verbosity if the provided severity is below or equals the configured one
 #define FAIR_LOGV(severity, verbosity) \
-    for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(fair::Severity::severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
-        fair::Logger(fair::Severity::severity, fair::Verbosity::verbosity, MSG_ORIGIN)
+    if (fair::Logger::SuppressSeverity(fair::Severity::severity)) ; else \
+        for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(fair::Severity::severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
+            fair::Logger(fair::Severity::severity, fair::Verbosity::verbosity, MSG_ORIGIN)
 
 // Log with fmt- or printf-like formatting
 #define FAIR_LOGF(severity, ...) LOG(severity) << fmt::format(__VA_ARGS__)
@@ -408,16 +423,19 @@ class Logger
 
 // Log an empty line
 #define FAIR_LOGN(severity) \
-    for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(fair::Severity::severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
-        fair::Logger(fair::Severity::severity, fair::Verbosity::verylow, MSG_ORIGIN).LogEmptyLine()
+    if (fair::Logger::SuppressSeverity(fair::Severity::severity)) ; else \
+        for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(fair::Severity::severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
+            fair::Logger(fair::Severity::severity, fair::Verbosity::verylow, MSG_ORIGIN).LogEmptyLine()
 
 // Log with custom file, line, function
 #define FAIR_LOGD(severity, file, line, f) \
-    for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
-        fair::Logger(severity, file, line, f)
+    if (fair::Logger::SuppressSeverity(severity)) ; else \
+        for (bool fairLOggerunLikelyvariable = false; fair::Logger::Logging(severity) && !fairLOggerunLikelyvariable; fairLOggerunLikelyvariable = true) \
+            fair::Logger(severity, file, line, f)
 
 #define FAIR_LOG_IF(severity, condition) \
-    for (bool fairLOggerunLikelyvariable2 = false; condition && !fairLOggerunLikelyvariable2; fairLOggerunLikelyvariable2 = true) \
-        LOG(severity)
+    if (fair::Logger::SuppressSeverity(fair::Severity::severity)) ; else \
+        for (bool fairLOggerunLikelyvariable2 = false; condition && !fairLOggerunLikelyvariable2; fairLOggerunLikelyvariable2 = true) \
+            LOG(severity)
 
 #endif // FAIR_LOGGER_H