Separate stdout and stderr in dlog output

Author: swift-kim

shell/platform/tizen/BUILD.gn

@@ -50,6 +50,7 @@ source_set("flutter_tizen") {
     "key_event_handler.cc",
     "tizen_embedder_engine.cc",
     "tizen_event_loop.cc",
+    "tizen_log.cc",
     "tizen_renderer.cc",
     "tizen_vsync_waiter.cc",
     "touch_event_handler.cc",

shell/platform/tizen/flutter_tizen.cc

@@ -5,9 +5,6 @@
 
 #include "public/flutter_tizen.h"
 
-#include <inttypes.h>
-#include <unistd.h>
-
 #include "flutter/shell/platform/common/cpp/client_wrapper/include/flutter/plugin_registrar.h"
 #include "flutter/shell/platform/common/cpp/client_wrapper/include/flutter/standard_message_codec.h"
 #include "flutter/shell/platform/common/cpp/incoming_message_dispatcher.h"
@@ -21,62 +18,10 @@ struct FlutterWindowControllerState {
   std::unique_ptr<TizenEmbedderEngine> engine;
 };
 
-// The pipe used for logging to dlog.
-static int logging_pipe[2];
-// The thread that constantly writes out stdout to dlog through the pipe.
-// Only one logging thread should exist per process.
-static pthread_t logging_thread;
-
-static void* LoggingFunction(void*) {
-  ssize_t size;
-  char buffer[1024];
-
-  while ((size = read(logging_pipe[0], buffer, sizeof(buffer) - 1)) > 0) {
-    buffer[size] = 0;
-    __dlog_print(LOG_ID_MAIN, DLOG_INFO, LOG_TAG, "%s", buffer);
-  }
-
-  close(logging_pipe[0]);
-  close(logging_pipe[1]);
-
-  return nullptr;
-}
-
-// Redirects the process's standard output/error to dlog for use by the flutter
-// tools.
-bool InitializeLogging() {
-  if (logging_thread) {
-    FT_LOGD("The logging thread already exists.");
-    return true;
-  }
-
-  if (pipe(logging_pipe) < 0) {
-    FT_LOGE("Failed to create a pipe.");
-    return false;
-  }
-
-  if (dup2(logging_pipe[1], 1) < 0 || dup2(logging_pipe[1], 2) < 0) {
-    FT_LOGE("Failed to duplicate file descriptors.");
-    return false;
-  }
-
-  if (pthread_create(&logging_thread, 0, LoggingFunction, 0) != 0) {
-    FT_LOGE("Failed to create a logging thread.");
-    logging_thread = 0;
-    return false;
-  }
-
-  if (pthread_detach(logging_thread) != 0) {
-    FT_LOGE("Failed to detach the logging thread.");
-    return false;
-  }
-  return true;
-}
-
 FlutterWindowControllerRef FlutterCreateWindow(
     const FlutterWindowProperties& window_properties,
     const FlutterEngineProperties& engine_properties) {
-  InitializeLogging();
+  StartLogging();
 
   auto state = std::make_unique<FlutterWindowControllerState>();
   state->engine = std::make_unique<TizenEmbedderEngine>(window_properties);
@@ -221,6 +166,7 @@ void FlutterNotifyLowMemoryWarning(FlutterWindowControllerRef controller) {
 
 void FlutterRotateWindow(FlutterWindowControllerRef controller,
                          int32_t degree) {
+  FT_LOGW("Deprecated API. Use SystemChrome.setPreferredOrientations instead.");
 }
 
 int64_t FlutterRegisterExternalTexture(

shell/platform/tizen/tizen_log.cc

@@ -0,0 +1,61 @@
+// Copyright 2021 Samsung Electronics Co., Ltd. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "tizen_log.h"
+
+#include <pthread.h>
+#include <unistd.h>
+
+static int stdout_pipe[2];
+static int stderr_pipe[2];
+static pthread_t stdout_thread;
+static pthread_t stderr_thread;
+static bool is_running = false;
+
+static void* LoggingFunction(void* arg) {
+  int* pipe = (int*)arg;
+  int priority = pipe == stdout_pipe ? DLOG_INFO : DLOG_ERROR;
+
+  ssize_t size;
+  char buffer[1024];
+
+  while ((size = read(pipe[0], buffer, sizeof(buffer) - 1)) > 0) {
+    buffer[size] = 0;
+    __dlog_print(LOG_ID_MAIN, priority, LOG_TAG, "%s", buffer);
+  }
+
+  close(pipe[0]);
+  close(pipe[1]);
+
+  return nullptr;
+}
+
+void StartLogging() {
+  if (is_running) {
+    FT_LOGD("The threads are already running.");
+    return;
+  }
+
+  if (pipe(stdout_pipe) < 0 || pipe(stderr_pipe) < 0) {
+    FT_LOGE("Failed to create pipes.");
+    return;
+  }
+
+  if (dup2(stdout_pipe[1], 1) < 0 || dup2(stderr_pipe[1], 2) < 0) {
+    FT_LOGE("Failed to duplicate file descriptors.");
+    return;
+  }
+
+  if (pthread_create(&stdout_thread, 0, LoggingFunction, stdout_pipe) != 0 ||
+      pthread_create(&stderr_thread, 0, LoggingFunction, stderr_pipe) != 0) {
+    FT_LOGE("Failed to create threads.");
+    return;
+  }
+
+  if (pthread_detach(stdout_thread) != 0 ||
+      pthread_detach(stderr_thread) != 0) {
+    FT_LOGW("Failed to detach threads.");
+  }
+  is_running = true;
+}

shell/platform/tizen/tizen_log.h

@@ -4,11 +4,15 @@
 
 #ifndef EMBEDDER_TIZEN_LOG_H_
 #define EMBEDDER_TIZEN_LOG_H_
+
 #include <dlog.h>
 
 #include <cassert>
 #include <cstdlib>
-#include <string>
+
+// Start logging threads which constantly redirect stdout/stderr to dlog.
+// The threads can be started only once per process.
+void StartLogging();
 
 #ifdef LOG_TAG
 #undef LOG_TAG
@@ -47,7 +51,7 @@
       FT_LOGE("RELEASE_ASSERT");     \
       abort();                       \
     }                                \
-  } while (0);
+  } while (0)
 
 #define FT_RELEASE_ASSERT_NOT_REACHED()    \
   do {                                     \