From 995dd0ba19c83744ffdb5e45e0fb8b54fa7b9d1e Mon Sep 17 00:00:00 2001
From: Marshall Greenblatt <magreenblatt@gmail.com>
Date: Tue, 29 Jan 2019 14:53:17 -0500
Subject: [PATCH] Suppress ERROR messages with log-severity=disable (issue
 #2581)

Also expose FATAL severity level.
---
 include/internal/cef_types.h   | 15 +++++++++++----
 libcef/common/cef_switches.cc  |  1 +
 libcef/common/cef_switches.h   |  1 +
 libcef/common/main_delegate.cc | 10 ++++++++++
 4 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/include/internal/cef_types.h b/include/internal/cef_types.h
index fb5f02cc6..f47e8608d 100644
--- a/include/internal/cef_types.h
+++ b/include/internal/cef_types.h
@@ -115,7 +115,13 @@ typedef enum {
   LOGSEVERITY_ERROR,
 
   ///
-  // Completely disable logging.
+  // FATAL logging.
+  ///
+  LOGSEVERITY_FATAL,
+
+  ///
+  // Disable logging to file for all messages, and to stderr for messages with
+  // severity less than FATAL.
   ///
   LOGSEVERITY_DISABLE = 99
 } cef_log_severity_t;
@@ -290,9 +296,10 @@ typedef struct _cef_settings_t {
 
   ///
   // The log severity. Only messages of this severity level or higher will be
-  // logged. Also configurable using the "log-severity" command-line switch with
-  // a value of "verbose", "info", "warning", "error", "error-report" or
-  // "disable".
+  // logged. When set to DISABLE no messages will be written to the log file,
+  // but FATAL messages will still be output to stderr. Also configurable using
+  // the "log-severity" command-line switch with a value of "verbose", "info",
+  // "warning", "error", "fatal" or "disable".
   ///
   cef_log_severity_t log_severity;
 
diff --git a/libcef/common/cef_switches.cc b/libcef/common/cef_switches.cc
index 3b7f4f872..520abcd25 100644
--- a/libcef/common/cef_switches.cc
+++ b/libcef/common/cef_switches.cc
@@ -12,6 +12,7 @@ const char kLogSeverity_Verbose[] = "verbose";
 const char kLogSeverity_Info[] = "info";
 const char kLogSeverity_Warning[] = "warning";
 const char kLogSeverity_Error[] = "error";
+const char kLogSeverity_Fatal[] = "fatal";
 const char kLogSeverity_Disable[] = "disable";
 
 // Path to resources directory.
diff --git a/libcef/common/cef_switches.h b/libcef/common/cef_switches.h
index 8e15d6100..ea00cd841 100644
--- a/libcef/common/cef_switches.h
+++ b/libcef/common/cef_switches.h
@@ -17,6 +17,7 @@ extern const char kLogSeverity_Verbose[];
 extern const char kLogSeverity_Info[];
 extern const char kLogSeverity_Warning[];
 extern const char kLogSeverity_Error[];
+extern const char kLogSeverity_Fatal[];
 extern const char kLogSeverity_Disable[];
 extern const char kResourcesDirPath[];
 extern const char kLocalesDirPath[];
diff --git a/libcef/common/main_delegate.cc b/libcef/common/main_delegate.cc
index e981036cb..348dc41cc 100644
--- a/libcef/common/main_delegate.cc
+++ b/libcef/common/main_delegate.cc
@@ -422,6 +422,9 @@ bool CefMainDelegate::BasicStartupComplete(int* exit_code) {
         case LOGSEVERITY_ERROR:
           log_severity = switches::kLogSeverity_Error;
           break;
+        case LOGSEVERITY_FATAL:
+          log_severity = switches::kLogSeverity_Fatal;
+          break;
         case LOGSEVERITY_DISABLE:
           log_severity = switches::kLogSeverity_Disable;
           break;
@@ -529,6 +532,9 @@ bool CefMainDelegate::BasicStartupComplete(int* exit_code) {
     } else if (base::LowerCaseEqualsASCII(log_severity_str,
                                           switches::kLogSeverity_Error)) {
       log_severity = logging::LOG_ERROR;
+    } else if (base::LowerCaseEqualsASCII(log_severity_str,
+                                          switches::kLogSeverity_Fatal)) {
+      log_severity = logging::LOG_FATAL;
     } else if (base::LowerCaseEqualsASCII(log_severity_str,
                                           switches::kLogSeverity_Disable)) {
       log_severity = LOGSEVERITY_DISABLE;
@@ -537,6 +543,10 @@ bool CefMainDelegate::BasicStartupComplete(int* exit_code) {
 
   if (log_severity == LOGSEVERITY_DISABLE) {
     log_settings.logging_dest = logging::LOG_NONE;
+    // By default, ERROR and FATAL messages will always be output to stderr due
+    // to the kAlwaysPrintErrorLevel value in base/logging.cc. We change the log
+    // level here so that only FATAL messages are output.
+    logging::SetMinLogLevel(logging::LOG_FATAL);
   } else {
     log_settings.logging_dest = logging::LOG_TO_ALL;
     logging::SetMinLogLevel(log_severity);