Mojo: Add basic logging facilities to environment.

I'll add nicer logging macros separately.

Also to do: We should also build mojo_public_environment_unittests
against mojo_environment_chromium (to test the "chromium"
implementation). I tried this manually (on a shared library build), and
the LoggerTests pass but the AsyncWaiterTests blow up.

R=darin@chromium.org

Review URL: https://codereview.chromium.org/330933004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@277189 0039d316-1c4b-4281-b951-d872f2087c98

9 files changed, 213 insertions, 0 deletions

diff --git a/mojo/environment/default_logger.cc b/mojo/environment/default_logger.cc
new file mode 100644
index 0000000..150dfa2
--- /dev/null
+++ b/mojo/environment/default_logger.cc
@@ -0,0 +1,15 @@
+// Copyright 2014 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 "mojo/public/cpp/environment/default_logger.h"
+
+#include "mojo/environment/default_logger_impl.h"
+
+namespace mojo {
+
+const MojoLogger* GetDefaultLogger() {
+  return internal::GetDefaultLoggerImpl();
+}
+
+}  // namespace mojo
diff --git a/mojo/environment/default_logger_impl.cc b/mojo/environment/default_logger_impl.cc
new file mode 100644
index 0000000..a2b06198
--- /dev/null
+++ b/mojo/environment/default_logger_impl.cc
@@ -0,0 +1,46 @@
+// Copyright 2014 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 "mojo/environment/default_logger_impl.h"
+
+#include "base/logging.h"
+#include "base/macros.h"
+
+namespace mojo {
+namespace internal {
+namespace {
+
+int GetChromiumLogLevel(MojoLogLevel log_level) {
+  // Our log levels correspond, except for "fatal":
+  COMPILE_ASSERT(logging::LOG_VERBOSE == MOJO_LOG_LEVEL_VERBOSE,
+                 verbose_log_level_value_mismatch);
+  COMPILE_ASSERT(logging::LOG_INFO == MOJO_LOG_LEVEL_INFO,
+                 info_log_level_value_mismatch);
+  COMPILE_ASSERT(logging::LOG_WARNING == MOJO_LOG_LEVEL_WARNING,
+                 warning_log_level_value_mismatch);
+  COMPILE_ASSERT(logging::LOG_ERROR == MOJO_LOG_LEVEL_ERROR,
+                 error_log_level_value_mismatch);
+
+  return (log_level >= MOJO_LOG_LEVEL_FATAL) ? logging::LOG_FATAL : log_level;
+}
+
+void LogMessage(MojoLogLevel log_level, const char* message) {
+  // TODO(vtl): Possibly, we should try to pull out the file and line number
+  // from |message|.
+  logging::LogMessage(__FILE__, __LINE__,
+                      GetChromiumLogLevel(log_level)).stream() << message;
+}
+
+const MojoLogger kDefaultLogger = {
+  LogMessage
+};
+
+}  // namespace
+
+const MojoLogger* GetDefaultLoggerImpl() {
+  return &kDefaultLogger;
+}
+
+}  // namespace internal
+}  // namespace mojo
diff --git a/mojo/environment/default_logger_impl.h b/mojo/environment/default_logger_impl.h
new file mode 100644
index 0000000..c87a727
--- /dev/null
+++ b/mojo/environment/default_logger_impl.h
@@ -0,0 +1,19 @@
+// Copyright 2014 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.
+
+#ifndef MOJO_ENVIRONMENT_DEFAULT_LOGGER_IMPL_H_
+#define MOJO_ENVIRONMENT_DEFAULT_LOGGER_IMPL_H_
+
+#include "mojo/environment/mojo_environment_impl_export.h"
+#include "mojo/public/c/environment/logger.h"
+
+namespace mojo {
+namespace internal {
+
+MOJO_ENVIRONMENT_IMPL_EXPORT const MojoLogger* GetDefaultLoggerImpl();
+
+}  // namespace internal
+}  // namespace mojo
+
+#endif  // MOJO_ENVIRONMENT_DEFAULT_LOGGER_IMPL_H_
diff --git a/mojo/mojo.gyp b/mojo/mojo.gyp
index 33d8628..aee37a4 100644
--- a/mojo/mojo.gyp
+++ b/mojo/mojo.gyp
@@ -397,6 +397,7 @@
       ],
       'sources': [
         'environment/default_async_waiter.cc',
+        'environment/default_logger.cc',
         'environment/environment.cc',
       ],
       'include_dirs': [
@@ -421,6 +422,8 @@
       'sources': [
         'environment/default_async_waiter_impl.cc',
         'environment/default_async_waiter_impl.h',
+        'environment/default_logger_impl.cc',
+        'environment/default_logger_impl.h',
       ],
       'include_dirs': [
         '..',
diff --git a/mojo/mojo_public.gypi b/mojo/mojo_public.gypi
index 760a849..516f6f6 100644
--- a/mojo/mojo_public.gypi
+++ b/mojo/mojo_public.gypi
@@ -161,6 +161,7 @@
       ],
       'sources': [
         'public/cpp/environment/tests/async_waiter_unittest.cc',
+        'public/cpp/environment/tests/logger_unittest.cc',
       ],
     },
     {
@@ -316,9 +317,13 @@
       'target_name': 'mojo_environment_standalone',
       'type': 'static_library',
       'sources': [
+        'public/c/environment/async_waiter.h',
+        'public/c/environment/logger.h',
         'public/cpp/environment/default_async_waiter.h',
+        'public/cpp/environment/default_logger.h',
         'public/cpp/environment/environment.h',
         'public/cpp/environment/lib/default_async_waiter.cc',
+        'public/cpp/environment/lib/default_logger.cc',
         'public/cpp/environment/lib/environment.cc',
       ],
       'include_dirs': [
diff --git a/mojo/public/c/environment/logger.h b/mojo/public/c/environment/logger.h
new file mode 100644
index 0000000..fd9a88f
--- /dev/null
+++ b/mojo/public/c/environment/logger.h
@@ -0,0 +1,32 @@
+// Copyright 2014 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.
+
+#ifndef MOJO_PUBLIC_C_ENVIRONMENT_LOGGER_H_
+#define MOJO_PUBLIC_C_ENVIRONMENT_LOGGER_H_
+
+#include <stdint.h>
+
+// |MojoLogLevel|: Used to specify the type of log message. Values are ordered
+// by severity (i.e., higher numerical values are more severe).
+
+typedef int32_t MojoLogLevel;
+
+#ifdef __cplusplus
+const MojoLogLevel MOJO_LOG_LEVEL_VERBOSE = -1;
+const MojoLogLevel MOJO_LOG_LEVEL_INFO = 0;
+const MojoLogLevel MOJO_LOG_LEVEL_WARNING = 1;
+const MojoLogLevel MOJO_LOG_LEVEL_ERROR = 2;
+const MojoLogLevel MOJO_LOG_LEVEL_FATAL = 3;
+#else
+#define MOJO_LOG_LEVEL_INFO ((MojoLogLevel) 0)
+#define MOJO_LOG_LEVEL_WARNING ((MojoLogLevel) 1)
+#define MOJO_LOG_LEVEL_ERROR ((MojoLogLevel) 2)
+#define MOJO_LOG_LEVEL_FATAL ((MojoLogLevel) 3)
+#endif
+
+struct MojoLogger {
+  void (*LogMessage)(MojoLogLevel log_level, const char* message);
+};
+
+#endif  // MOJO_PUBLIC_C_ENVIRONMENT_LOGGER_H_
diff --git a/mojo/public/cpp/environment/default_logger.h b/mojo/public/cpp/environment/default_logger.h
new file mode 100644
index 0000000..b022393
--- /dev/null
+++ b/mojo/public/cpp/environment/default_logger.h
@@ -0,0 +1,17 @@
+// Copyright 2014 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.
+
+#ifndef MOJO_PUBLIC_CPP_ENVIRONMENT_DEFAULT_LOGGER_H_
+#define MOJO_PUBLIC_CPP_ENVIRONMENT_DEFAULT_LOGGER_H_
+
+#include "mojo/public/c/environment/logger.h"
+
+namespace mojo {
+
+// Returns a default implementation of |MojoLogger|.
+const MojoLogger* GetDefaultLogger();
+
+}  // namespace mojo
+
+#endif  // MOJO_PUBLIC_CPP_ENVIRONMENT_DEFAULT_LOGGER_H_
diff --git a/mojo/public/cpp/environment/lib/default_logger.cc b/mojo/public/cpp/environment/lib/default_logger.cc
new file mode 100644
index 0000000..100b0d1
--- /dev/null
+++ b/mojo/public/cpp/environment/lib/default_logger.cc
@@ -0,0 +1,47 @@
+// Copyright 2014 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 "mojo/public/cpp/environment/default_logger.h"
+
+#include <stdio.h>
+#include <stdlib.h>  // For |abort()|.
+
+namespace mojo {
+namespace {
+
+const char* GetLogLevelString(MojoLogLevel log_level) {
+  if (log_level < MOJO_LOG_LEVEL_VERBOSE)
+    return "VERBOSE";
+  switch (log_level) {
+    case MOJO_LOG_LEVEL_VERBOSE:
+      return "VERBOSE";
+    case MOJO_LOG_LEVEL_INFO:
+      return "INFO";
+    case MOJO_LOG_LEVEL_WARNING:
+      return "WARNING";
+    case MOJO_LOG_LEVEL_ERROR:
+      return "ERROR";
+  }
+  // Consider everything higher to be fatal.
+  return "FATAL";
+}
+
+void LogMessage(MojoLogLevel log_level, const char* message) {
+  // TODO(vtl): Add timestamp also?
+  fprintf(stderr, "%s:%s\n", GetLogLevelString(log_level), message);
+  if (log_level >= MOJO_LOG_LEVEL_FATAL)
+    abort();
+}
+
+const MojoLogger kDefaultLogger = {
+  LogMessage
+};
+
+}  // namespace
+
+const MojoLogger* GetDefaultLogger() {
+  return &kDefaultLogger;
+}
+
+}  // namespace mojo
diff --git a/mojo/public/cpp/environment/tests/logger_unittest.cc b/mojo/public/cpp/environment/tests/logger_unittest.cc
new file mode 100644
index 0000000..305d0c4
--- /dev/null
+++ b/mojo/public/cpp/environment/tests/logger_unittest.cc
@@ -0,0 +1,29 @@
+// Copyright 2014 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 "mojo/public/cpp/environment/default_logger.h"
+#include "mojo/public/cpp/environment/environment.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace mojo {
+namespace {
+
+TEST(LoggerTest, Basic) {
+  Environment environment;
+  const MojoLogger* const logger = GetDefaultLogger();
+
+  logger->LogMessage(MOJO_LOG_LEVEL_VERBOSE-1, "Logged at VERBOSE-1 level");
+  logger->LogMessage(MOJO_LOG_LEVEL_VERBOSE, "Logged at VERBOSE level");
+  logger->LogMessage(MOJO_LOG_LEVEL_INFO, "Logged at INFO level");
+  logger->LogMessage(MOJO_LOG_LEVEL_WARNING, "Logged at WARNING level");
+  logger->LogMessage(MOJO_LOG_LEVEL_ERROR, "Logged at ERROR level");
+
+  // This should kill us:
+  EXPECT_DEATH({
+    logger->LogMessage(MOJO_LOG_LEVEL_FATAL, "Logged at FATAL level");
+  }, "");
+}
+
+}  // namespace
+}  // namespace mojo