From 42b10209fec1079cc020a71998e8e920e8006460 Mon Sep 17 00:00:00 2001
From: Satori <comfycallum@gmail.com>
Date: Sun, 6 Sep 2020 19:20:59 +0100
Subject: [PATCH] [Base] Add support for multiple log sinks in Logger

---
 src/xenia/base/logging.cc | 70 ++++++++++++++++++++++++++-------------
 src/xenia/base/logging.h  | 25 ++++++++++++++
 2 files changed, 72 insertions(+), 23 deletions(-)

diff --git a/src/xenia/base/logging.cc b/src/xenia/base/logging.cc
index 8584892d4..9a565fd64 100644
--- a/src/xenia/base/logging.cc
+++ b/src/xenia/base/logging.cc
@@ -66,30 +66,30 @@ struct LogLine {
 
 thread_local char thread_log_buffer_[64 * 1024];
 
+
+void FileLogSink::Write(const char* buf, size_t size) {
+  if (file_) {
+    fwrite(buf, 1, size, file_);
+  }
+}
+
+void FileLogSink::Flush() {
+  if (file_) {
+    fflush(file_);
+  }
+}
+
 class Logger {
  public:
   explicit Logger(const std::string_view app_name)
-      : file_(nullptr),
-        running_(true),
+      : 
         wait_strategy_(),
         claim_strategy_(kBlockCount, wait_strategy_),
-        consumed_(wait_strategy_) {
+        consumed_(wait_strategy_),
+        running_(true) {
     claim_strategy_.add_claim_barrier(consumed_);
 
-    if (cvars::log_file.empty()) {
-      // Default to app name.
-      auto file_name = fmt::format("{}.log", app_name);
-      auto file_path = std::filesystem::path(file_name);
-      xe::filesystem::CreateParentFolder(file_path);
-      file_ = xe::filesystem::OpenFile(file_path, "wt");
-    } else {
-      if (cvars::log_file == "stdout") {
-        file_ = stdout;
-      } else {
-        xe::filesystem::CreateParentFolder(cvars::log_file);
-        file_ = xe::filesystem::OpenFile(cvars::log_file, "wt");
-      }
-    }
+   
 
     write_thread_ =
         xe::threading::Thread::Create({}, [this]() { WriteThread(); });
@@ -99,8 +99,10 @@ class Logger {
   ~Logger() {
     running_ = false;
     xe::threading::Wait(write_thread_.get(), true);
-    fflush(file_);
-    fclose(file_);
+  }
+
+  void AddLogSink(std::unique_ptr<LogSink> sink) {
+    sinks_.push_back(std::move(sink));
   }
 
  private:
@@ -126,14 +128,14 @@ class Logger {
   dp::multi_threaded_claim_strategy<dp::spin_wait_strategy> claim_strategy_;
   dp::sequence_barrier<dp::spin_wait_strategy> consumed_;
 
-  FILE* file_;
+  std::vector<std::unique_ptr<LogSink>> sinks_;
 
   std::atomic<bool> running_;
   std::unique_ptr<xe::threading::Thread> write_thread_;
 
   void Write(const char* buf, size_t size) {
-    if (file_) {
-      fwrite(buf, 1, size, file_);
+    for (const auto& sink : sinks_) {
+      sink->Write(buf, size);
     }
     if (cvars::log_to_debugprint) {
       debugging::DebugPrint("{}", std::string_view(buf, size));
@@ -246,7 +248,9 @@ class Logger {
         desired_count = 1;
 
         if (cvars::flush_log) {
-          fflush(file_);
+          for (const auto& sink : sinks_) {
+            sink->Flush();
+          }
         }
 
         idle_loops = 0;
@@ -291,6 +295,26 @@ class Logger {
 void InitializeLogging(const std::string_view app_name) {
   auto mem = memory::AlignedAlloc<Logger>(0x10);
   logger_ = new (mem) Logger(app_name);
+
+  FILE* file = nullptr;
+
+   if (cvars::log_file.empty()) {
+    // Default to app name.
+    auto file_name = fmt::format("{}.log", app_name);
+    auto file_path = std::filesystem::path(file_name);
+    xe::filesystem::CreateParentFolder(file_path);
+
+    file = xe::filesystem::OpenFile(file_path, "wt");
+  } else {
+    if (cvars::log_file == "stdout") {
+      file = stdout;
+    } else {
+      xe::filesystem::CreateParentFolder(cvars::log_file);
+      file = xe::filesystem::OpenFile(cvars::log_file, "wt");
+    }
+  }
+  auto sink = std::make_unique<FileLogSink>(file);
+  logger_->AddLogSink(std::move(sink));
 }
 
 void ShutdownLogging() {
diff --git a/src/xenia/base/logging.h b/src/xenia/base/logging.h
index 864d5d620..d2df15cce 100644
--- a/src/xenia/base/logging.h
+++ b/src/xenia/base/logging.h
@@ -34,6 +34,31 @@ enum class LogLevel {
   Trace,
 };
 
+class LogSink {
+ public:
+  virtual ~LogSink() = default;
+
+  virtual void Write(const char* buf, size_t size) = 0;
+  virtual void Flush() = 0;
+};
+
+class FileLogSink final : public LogSink {
+ public:
+  explicit FileLogSink(FILE* file) : file_(file) {}
+  virtual ~FileLogSink() {
+    if (file_) {
+      fflush(file_);
+      fclose(file_);
+    }
+  }
+
+  void Write(const char* buf, size_t size) override;
+  void Flush() override;
+
+ private:
+  FILE* file_;
+};
+
 // Initializes the logging system and any outputs requested.
 // Must be called on startup.
 void InitializeLogging(const std::string_view app_name);