logging: add a LoggerDB::internalWarning() function

[folly.git] / folly / experimental / logging / LogCategory.cpp

diff --git a/folly/experimental/logging/LogCategory.cpp b/folly/experimental/logging/LogCategory.cpp
index f6fcc1098f62dcb00e0ab4177fe7ab0b31be6b1e..6f02c9dca6a090f6d474907747fcab70920ca4d6 100644 (file)
--- a/folly/experimental/logging/LogCategory.cpp
+++ b/folly/experimental/logging/LogCategory.cpp
@@ -42,7 +42,7 @@ LogCategory::LogCategory(StringPiece name, LogCategory* parent)
   parent_->firstChild_ = this;
 }
 
-void LogCategory::processMessage(const LogMessage& message) {
+void LogCategory::processMessage(const LogMessage& message) const {
   // Make a copy of any attached LogHandlers, so we can release the handlers_
   // lock before holding them.
   //
@@ -69,19 +69,18 @@ void LogCategory::processMessage(const LogMessage& message) {
 
   for (size_t n = 0; n < numHandlers; ++n) {
     try {
-      handlers[n]->log(message, this);
+      handlers[n]->handleMessage(message, this);
     } catch (const std::exception& ex) {
-      // If a LogHandler throws an exception, complain about this fact on
-      // stderr to avoid swallowing the error information completely.  We
-      // don't propagate the exception up to our caller: most code does not
-      // prepare for log statements to throw.  We also want to continue
-      // trying to log the message to any other handlers attached to ourself
-      // or one of our parent categories.
-      fprintf(
-          stderr,
-          "WARNING: log handler for category %s threw an error: %s\n",
-          name_.c_str(),
-          folly::exceptionStr(ex).c_str());
+      // Use LoggerDB::internalWarning() to report the error, but continue
+      // trying to log the message to any other handlers attached to ourself or
+      // one of our parent categories.
+      LoggerDB::internalWarning(
+          __FILE__,
+          __LINE__,
+          "log handler for category \"",
+          name_,
+          "\" threw an error: ",
+          folly::exceptionStr(ex));
     }
   }
 
@@ -121,11 +120,16 @@ void LogCategory::setLevel(LogLevel level, bool inherit) {
 }
 
 void LogCategory::setLevelLocked(LogLevel level, bool inherit) {
-  // Truncate to LogLevel::MAX_LEVEL to make sure it does not conflict
-  // with our flag bits.
+  // Clamp the value to MIN_LEVEL and MAX_LEVEL.
+  //
+  // This makes sure that UNINITIALIZED is always less than any valid level
+  // value, and that level values cannot conflict with our flag bits.
   if (level > LogLevel::MAX_LEVEL) {
     level = LogLevel::MAX_LEVEL;
+  } else if (level < LogLevel::MIN_LEVEL) {
+    level = LogLevel::MIN_LEVEL;
   }
+
   // Make sure the inherit flag is always off for the root logger.
   if (!parent_) {
     inherit = false;
@@ -161,6 +165,11 @@ void LogCategory::updateEffectiveLevel(LogLevel newEffectiveLevel) {
     return;
   }
 
+  // Update all of the values in xlogLevels_
+  for (auto* levelPtr : xlogLevels_) {
+    levelPtr->store(newEffectiveLevel, std::memory_order_release);
+  }
+
   // Update all children loggers
   LogCategory* child = firstChild_;
   while (child != nullptr) {
@@ -180,4 +189,8 @@ void LogCategory::parentLevelUpdated(LogLevel parentEffectiveLevel) {
   auto newEffectiveLevel = std::min(myLevel, parentEffectiveLevel);
   updateEffectiveLevel(newEffectiveLevel);
 }
+
+void LogCategory::registerXlogLevel(std::atomic<LogLevel>* levelPtr) {
+  xlogLevels_.push_back(levelPtr);
+}
 }