Change logging to syslog; fix CRD in Yosemite

remoting/host/logging_mac.cc

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "remoting/host/logging.h"
+
+#include <asl.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "base/logging.h"
+#include "base/scoped_generic.h"
+#include "base/strings/string_number_conversions.h"
+
+namespace remoting {
+
+namespace {
+
+const char kChromotingLoggingFacility[] = "org.chromium.chromoting";
+
+// Define a scoper for objects allocated by asl_new.
+struct ScopedAslMsgTraits {
+  static aslmsg InvalidValue() {
+    return nullptr;
+  }
+  static void Free(aslmsg msg) {
+    asl_free(msg);
+  }
+};
+typedef base::ScopedGeneric<aslmsg, ScopedAslMsgTraits> ScopedAslMsg;
+
+// Logging message handler that writes to syslog.
+// The log can be obtained by running the following in a terminal:
+// syslog -k Facility org.chromium.chromoting
+bool LogMessageToAsl(
+    logging::LogSeverity severity,
+    const char* file,
+    int line,
+    size_t message_start,
+    const std::string& message) {
+  int level;
+  switch(severity) {
+    case logging::LOG_INFO:
+      level = ASL_LEVEL_NOTICE;
+      break;
+    case logging::LOG_WARNING:
+      level = ASL_LEVEL_WARNING;
+      break;
+    case logging::LOG_ERROR:
+      level = ASL_LEVEL_ERR;
+      break;
+    case logging::LOG_FATAL:
+      level = ASL_LEVEL_EMERG;
+      break;
+    default:
+      // 'notice' is the lowest priority that the asl libraries will log by
+      // default.
+      level = ASL_LEVEL_NOTICE;
+      break;
+  }
+
+  ScopedAslMsg asl_message(asl_new(ASL_TYPE_MSG));
+  if (!asl_message.is_valid())
+    return false;
+
+  if (asl_set(asl_message.get(), ASL_KEY_FACILITY,
+              kChromotingLoggingFacility) != 0)
+    return false;
+
+  if (asl_set(asl_message.get(), ASL_KEY_LEVEL,
+              base::IntToString(level).c_str()) != 0)
+    return false;
+
+  // Restrict read access to the message to root and the current user.
+  if (asl_set(asl_message.get(), ASL_KEY_READ_UID,
+              base::IntToString(geteuid()).c_str()) != 0)
+    return false;
+
+  if (asl_set(asl_message.get(), ASL_KEY_MSG,
+              message.c_str() + message_start) != 0)
+    return false;
+
+  asl_send(nullptr, asl_message.get());
+
+  // Don't prevent message from being logged by traditional means.
+  return false;
+}
+
+}  // namespace
+
+void InitHostLogging() {
+  // Write logs to the system debug log.
+  logging::LoggingSettings settings;
+  settings.logging_dest = logging::LOG_TO_SYSTEM_DEBUG_LOG;
+  logging::InitLogging(settings);
+
+  // Write logs to syslog as well.
+  logging::SetLogMessageHandler(LogMessageToAsl);
+}
+
+}  // namespace remoting