New logging system

14 files changed, 743 insertions, 74 deletions

diff --git a/src/citra/citra.cpp b/src/citra/citra.cpp
index f2aeb510e..7c031ce8d 100644
--- a/src/citra/citra.cpp
+++ b/src/citra/citra.cpp
@@ -2,8 +2,12 @@
 // Licensed under GPLv2
 // Refer to the license.txt file included.
 
+#include <thread>
+
 #include "common/common.h"
-#include "common/log_manager.h"
+#include "common/logging/text_formatter.h"
+#include "common/logging/backend.h"
+#include "common/scope_exit.h"
 
 #include "core/settings.h"
 #include "core/system.h"
@@ -15,7 +19,12 @@
 
 /// Application entry point
 int __cdecl main(int argc, char **argv) {
-    LogManager::Init();
+    std::shared_ptr<Log::Logger> logger = Log::InitGlobalLogger();
+    std::thread logging_thread(Log::TextLoggingLoop, logger);
+    SCOPE_EXIT({
+        logger->Close();
+        logging_thread.join();
+    });
 
     if (argc < 2) {
         ERROR_LOG(BOOT, "Failed to load ROM: No ROM specified");
@@ -24,9 +33,6 @@ int __cdecl main(int argc, char **argv) {
 
     Config config;
 
-    if (!Settings::values.enable_log)
-        LogManager::Shutdown();
-
     std::string boot_filename = argv[1];
     EmuWindow_GLFW* emu_window = new EmuWindow_GLFW;
 
diff --git a/src/citra_qt/main.cpp b/src/citra_qt/main.cpp
index b4e3ad964..2e3025295 100644
--- a/src/citra_qt/main.cpp
+++ b/src/citra_qt/main.cpp
@@ -1,3 +1,5 @@
+#include <thread>
+
 #include <QtGui>
 #include <QDesktopWidget>
 #include <QFileDialog>
@@ -5,8 +7,13 @@
 #include "main.hxx"
 
 #include "common/common.h"
-#include "common/platform.h"
 #include "common/log_manager.h"
+#include "common/logging/text_formatter.h"
+#include "common/logging/log.h"
+#include "common/logging/backend.h"
+#include "common/platform.h"
+#include "common/scope_exit.h"
+
 #if EMU_PLATFORM == PLATFORM_LINUX
 #include <unistd.h>
 #endif
@@ -33,10 +40,8 @@
 
 #include "version.h"
 
-
 GMainWindow::GMainWindow()
 {
-    LogManager::Init();
 
     Pica::g_debug_context = Pica::DebugContext::Construct();
 
@@ -271,6 +276,13 @@ void GMainWindow::closeEvent(QCloseEvent* event)
 
 int __cdecl main(int argc, char* argv[])
 {
+    std::shared_ptr<Log::Logger> logger = Log::InitGlobalLogger();
+    std::thread logging_thread(Log::TextLoggingLoop, logger);
+    SCOPE_EXIT({
+        logger->Close();
+        logging_thread.join();
+    });
+
     QApplication::setAttribute(Qt::AA_X11InitThreads);
     QApplication app(argc, argv);
     GMainWindow main_window;
diff --git a/src/common/CMakeLists.txt b/src/common/CMakeLists.txt
index 1dbc5db21..7c1d3d1dc 100644
--- a/src/common/CMakeLists.txt
+++ b/src/common/CMakeLists.txt
@@ -11,6 +11,8 @@ set(SRCS
             hash.cpp
             key_map.cpp
             log_manager.cpp
+            logging/text_formatter.cpp
+            logging/backend.cpp
             math_util.cpp
             mem_arena.cpp
             memory_util.cpp
@@ -32,6 +34,7 @@ set(HEADERS
             common_funcs.h
             common_paths.h
             common_types.h
+            concurrent_ring_buffer.h
             console_listener.h
             cpu_detect.h
             debug_interface.h
@@ -45,6 +48,9 @@ set(HEADERS
             linear_disk_cache.h
             log.h
             log_manager.h
+            logging/text_formatter.h
+            logging/log.h
+            logging/backend.h
             math_util.h
             mem_arena.h
             memory_util.h
diff --git a/src/common/common_types.h b/src/common/common_types.h
index fcc8b9a4e..c74c74f0f 100644
--- a/src/common/common_types.h
+++ b/src/common/common_types.h
@@ -41,8 +41,6 @@ typedef std::int64_t s64; ///< 64-bit signed int
 typedef float   f32; ///< 32-bit floating point
 typedef double  f64; ///< 64-bit floating point
 
-#include "common/common.h"
-
 /// Union for fast 16-bit type casting
 union t16 {
     u8  _u8[2];             ///< 8-bit unsigned char(s)
diff --git a/src/common/concurrent_ring_buffer.h b/src/common/concurrent_ring_buffer.h
new file mode 100644
index 000000000..2951d93db
--- /dev/null
+++ b/src/common/concurrent_ring_buffer.h
@@ -0,0 +1,164 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <array>
+#include <condition_variable>
+#include <cstdint>
+#include <mutex>
+#include <thread>
+
+#include "common/common.h" // for NonCopyable
+#include "common/log.h" // for _dbg_assert_
+
+namespace Common {
+
+/**
+ * A MPMC (Multiple-Producer Multiple-Consumer) concurrent ring buffer. This data structure permits
+ * multiple threads to push and pop from a queue of bounded size.
+ */
+template <typename T, size_t ArraySize>
+class ConcurrentRingBuffer : private NonCopyable {
+public:
+    /// Value returned by the popping functions when the queue has been closed.
+    static const size_t QUEUE_CLOSED = -1;
+
+    ConcurrentRingBuffer() {}
+
+    ~ConcurrentRingBuffer() {
+        // If for whatever reason the queue wasn't completely drained, destroy the left over items.
+        for (size_t i = reader_index, end = writer_index; i != end; i = (i + 1) % ArraySize) {
+            Data()[i].~T();
+        }
+    }
+
+    /**
+     * Pushes a value to the queue. If the queue is full, this method will block. Does nothing if
+     * the queue is closed.
+     */
+    void Push(T val) {
+        std::unique_lock<std::mutex> lock(mutex);
+        if (closed) {
+            return;
+        }
+
+        // If the buffer is full, wait
+        writer.wait(lock, [&]{
+            return (writer_index + 1) % ArraySize != reader_index;
+        });
+
+        T* item = &Data()[writer_index];
+        new (item) T(std::move(val));
+
+        writer_index = (writer_index + 1) % ArraySize;
+
+        // Wake up waiting readers
+        lock.unlock();
+        reader.notify_one();
+    }
+
+    /**
+     * Pops up to `dest_len` items from the queue, storing them in `dest`. This function will not
+     * block, and might return 0 values if there are no elements in the queue when it is called.
+     *
+     * @return The number of elements stored in `dest`. If the queue has been closed, returns
+     *          `QUEUE_CLOSED`.
+     */
+    size_t Pop(T* dest, size_t dest_len) {
+        std::unique_lock<std::mutex> lock(mutex);
+        if (closed && !CanRead()) {
+            return QUEUE_CLOSED;
+        }
+        return PopInternal(dest, dest_len);
+    }
+
+    /**
+     * Pops up to `dest_len` items from the queue, storing them in `dest`. This function will block
+     * if there are no elements in the queue when it is called.
+     *
+     * @return The number of elements stored in `dest`. If the queue has been closed, returns
+     *         `QUEUE_CLOSED`.
+     */
+    size_t BlockingPop(T* dest, size_t dest_len) {
+        std::unique_lock<std::mutex> lock(mutex);
+        if (closed && !CanRead()) {
+            return QUEUE_CLOSED;
+        }
+
+        while (!CanRead()) {
+            reader.wait(lock);
+            if (closed && !CanRead()) {
+                return QUEUE_CLOSED;
+            }
+        }
+        _dbg_assert_(Common, CanRead());
+        return PopInternal(dest, dest_len);
+    }
+
+    /**
+     * Closes the queue. After calling this method, `Push` operations won't have any effect, and
+     * `PopMany` and `PopManyBlock` will start returning `QUEUE_CLOSED`. This is intended to allow
+     * a graceful shutdown of all consumers.
+     */
+    void Close() {
+        std::unique_lock<std::mutex> lock(mutex);
+        closed = true;
+        // We need to wake up any reader that are waiting for an item that will never come.
+        lock.unlock();
+        reader.notify_all();
+    }
+
+    /// Returns true if `Close()` has been called.
+    bool IsClosed() const {
+        return closed;
+    }
+
+private:
+    size_t PopInternal(T* dest, size_t dest_len) {
+        size_t output_count = 0;
+        while (output_count < dest_len && CanRead()) {
+            _dbg_assert_(Common, CanRead());
+
+            T* item = &Data()[reader_index];
+            T out_val = std::move(*item);
+            item->~T();
+
+            size_t prev_index = (reader_index + ArraySize - 1) % ArraySize;
+            reader_index = (reader_index + 1) % ArraySize;
+            if (writer_index == prev_index) {
+                writer.notify_one();
+            }
+            dest[output_count++] = std::move(out_val);
+        }
+        return output_count;
+    }
+
+    bool CanRead() const {
+        return reader_index != writer_index;
+    }
+
+    T* Data() {
+        return static_cast<T*>(static_cast<void*>(&storage));
+    }
+
+    /// Storage for entries
+    typename std::aligned_storage<ArraySize * sizeof(T),
+                                  std::alignment_of<T>::value>::type storage;
+
+    /// Data is valid in the half-open interval [reader, writer). If they are `QUEUE_CLOSED` then the
+    /// queue has been closed.
+    size_t writer_index = 0, reader_index = 0;
+    // True if the queue has been closed.
+    bool closed = false;
+
+    /// Mutex that protects the entire data structure.
+    std::mutex mutex;
+    /// Signaling wakes up reader which is waiting for storage to be non-empty.
+    std::condition_variable reader;
+    /// Signaling wakes up writer which is waiting for storage to be non-full.
+    std::condition_variable writer;
+};
+
+} // namespace
diff --git a/src/common/log.h b/src/common/log.h
index 78f0dae4d..105db9802 100644
--- a/src/common/log.h
+++ b/src/common/log.h
@@ -6,6 +6,7 @@
 
 #include "common/common_funcs.h"
 #include "common/msg_handler.h"
+#include "common/logging/log.h"
 
 #ifndef LOGGING
 #define LOGGING
@@ -24,45 +25,45 @@ namespace LogTypes
 {
 
 enum LOG_TYPE {
-    ACTIONREPLAY,
-    AUDIO,
-    AUDIO_INTERFACE,
+    //ACTIONREPLAY,
+    //AUDIO,
+    //AUDIO_INTERFACE,
     BOOT,
-    COMMANDPROCESSOR,
+    //COMMANDPROCESSOR,
     COMMON,
-    CONSOLE,
+    //CONSOLE,
     CONFIG,
-    DISCIO,
-    FILEMON,
-    DSPHLE,
-    DSPLLE,
-    DSP_MAIL,
-    DSPINTERFACE,
-    DVDINTERFACE,
-    DYNA_REC,
-    EXPANSIONINTERFACE,
-    GDB_STUB,
+    //DISCIO,
+    //FILEMON,
+    //DSPHLE,
+    //DSPLLE,
+    //DSP_MAIL,
+    //DSPINTERFACE,
+    //DVDINTERFACE,
+    //DYNA_REC,
+    //EXPANSIONINTERFACE,
+    //GDB_STUB,
     ARM11,
     GSP,
     OSHLE,
     MASTER_LOG,
     MEMMAP,
-    MEMCARD_MANAGER,
-    OSREPORT,
-    PAD,
-    PROCESSORINTERFACE,
-    PIXELENGINE,
-    SERIALINTERFACE,
-    SP1,
-    STREAMINGINTERFACE,
+    //MEMCARD_MANAGER,
+    //OSREPORT,
+    //PAD,
+    //PROCESSORINTERFACE,
+    //PIXELENGINE,
+    //SERIALINTERFACE,
+    //SP1,
+    //STREAMINGINTERFACE,
     VIDEO,
-    VIDEOINTERFACE,
+    //VIDEOINTERFACE,
     LOADER,
     FILESYS,
-    WII_IPC_DVD,
-    WII_IPC_ES,
-    WII_IPC_FILEIO,
-    WII_IPC_HID,
+    //WII_IPC_DVD,
+    //WII_IPC_ES,
+    //WII_IPC_FILEIO,
+    //WII_IPC_HID,
     KERNEL,
     SVC,
     HLE,
@@ -70,7 +71,7 @@ enum LOG_TYPE {
     GPU,
     HW,
     TIME,
-    NETPLAY,
+    //NETPLAY,
     GUI,
 
     NUMBER_OF_LOGS // Must be last
@@ -118,12 +119,19 @@ void GenericLog(LOGTYPES_LEVELS level, LOGTYPES_TYPE type, const char*file, int
         GenericLog(v, t, __FILE__, __LINE__, __func__, __VA_ARGS__); \
     }
 
-#define OS_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LOS, __VA_ARGS__) } while (0)
-#define ERROR_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LERROR, __VA_ARGS__) } while (0)
-#define WARN_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LWARNING, __VA_ARGS__) } while (0)
-#define NOTICE_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LNOTICE, __VA_ARGS__) } while (0)
-#define INFO_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LINFO, __VA_ARGS__) } while (0)
-#define DEBUG_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LDEBUG, __VA_ARGS__) } while (0)
+//#define OS_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LOS, __VA_ARGS__) } while (0)
+//#define ERROR_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LERROR, __VA_ARGS__) } while (0)
+//#define WARN_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LWARNING, __VA_ARGS__) } while (0)
+//#define NOTICE_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LNOTICE, __VA_ARGS__) } while (0)
+//#define INFO_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LINFO, __VA_ARGS__) } while (0)
+//#define DEBUG_LOG(t,...) do { GENERIC_LOG(LogTypes::t, LogTypes::LDEBUG, __VA_ARGS__) } while (0)
+
+#define OS_LOG(t,...) LOG_INFO(Common, __VA_ARGS__)
+#define ERROR_LOG(t,...) LOG_ERROR(Common_Filesystem, __VA_ARGS__)
+#define WARN_LOG(t,...) LOG_WARNING(Kernel_SVC, __VA_ARGS__)
+#define NOTICE_LOG(t,...) LOG_INFO(Service, __VA_ARGS__)
+#define INFO_LOG(t,...) LOG_INFO(Service_FS, __VA_ARGS__)
+#define DEBUG_LOG(t,...) LOG_DEBUG(Common, __VA_ARGS__)
 
 #if MAX_LOGLEVEL >= DEBUG_LEVEL
 #define _dbg_assert_(_t_, _a_) \
diff --git a/src/common/log_manager.cpp b/src/common/log_manager.cpp
index 128c15388..adc17444c 100644
--- a/src/common/log_manager.cpp
+++ b/src/common/log_manager.cpp
@@ -30,49 +30,49 @@ LogManager::LogManager()
     m_Log[LogTypes::BOOT]               = new LogContainer("BOOT",              "Boot");
     m_Log[LogTypes::COMMON]             = new LogContainer("COMMON",            "Common");
     m_Log[LogTypes::CONFIG]             = new LogContainer("CONFIG",            "Configuration");
-    m_Log[LogTypes::DISCIO]             = new LogContainer("DIO",               "Disc IO");
-    m_Log[LogTypes::FILEMON]            = new LogContainer("FileMon",           "File Monitor");
-    m_Log[LogTypes::PAD]                = new LogContainer("PAD",               "Pad");
-    m_Log[LogTypes::PIXELENGINE]        = new LogContainer("PE",                "PixelEngine");
-    m_Log[LogTypes::COMMANDPROCESSOR]   = new LogContainer("CP",                "CommandProc");
-    m_Log[LogTypes::VIDEOINTERFACE]     = new LogContainer("VI",                "VideoInt");
-    m_Log[LogTypes::SERIALINTERFACE]    = new LogContainer("SI",                "SerialInt");
-    m_Log[LogTypes::PROCESSORINTERFACE] = new LogContainer("PI",                "ProcessorInt");
+    //m_Log[LogTypes::DISCIO]             = new LogContainer("DIO",               "Disc IO");
+    //m_Log[LogTypes::FILEMON]            = new LogContainer("FileMon",           "File Monitor");
+    //m_Log[LogTypes::PAD]                = new LogContainer("PAD",               "Pad");
+    //m_Log[LogTypes::PIXELENGINE]        = new LogContainer("PE",                "PixelEngine");
+    //m_Log[LogTypes::COMMANDPROCESSOR]   = new LogContainer("CP",                "CommandProc");
+    //m_Log[LogTypes::VIDEOINTERFACE]     = new LogContainer("VI",                "VideoInt");
+    //m_Log[LogTypes::SERIALINTERFACE]    = new LogContainer("SI",                "SerialInt");
+    //m_Log[LogTypes::PROCESSORINTERFACE] = new LogContainer("PI",                "ProcessorInt");
     m_Log[LogTypes::MEMMAP]             = new LogContainer("MI",                "MI & memmap");
-    m_Log[LogTypes::SP1]                = new LogContainer("SP1",               "Serial Port 1");
-    m_Log[LogTypes::STREAMINGINTERFACE] = new LogContainer("Stream",            "StreamingInt");
-    m_Log[LogTypes::DSPINTERFACE]       = new LogContainer("DSP",               "DSPInterface");
-    m_Log[LogTypes::DVDINTERFACE]       = new LogContainer("DVD",               "DVDInterface");
+    //m_Log[LogTypes::SP1]                = new LogContainer("SP1",               "Serial Port 1");
+    //m_Log[LogTypes::STREAMINGINTERFACE] = new LogContainer("Stream",            "StreamingInt");
+    //m_Log[LogTypes::DSPINTERFACE]       = new LogContainer("DSP",               "DSPInterface");
+    //m_Log[LogTypes::DVDINTERFACE]       = new LogContainer("DVD",               "DVDInterface");
     m_Log[LogTypes::GSP]                = new LogContainer("GSP",               "GSP");
-    m_Log[LogTypes::EXPANSIONINTERFACE] = new LogContainer("EXI",               "ExpansionInt");
-    m_Log[LogTypes::GDB_STUB]           = new LogContainer("GDB_STUB",          "GDB Stub");
-    m_Log[LogTypes::AUDIO_INTERFACE]    = new LogContainer("AI",                "AudioInt");
+    //m_Log[LogTypes::EXPANSIONINTERFACE] = new LogContainer("EXI",               "ExpansionInt");
+    //m_Log[LogTypes::GDB_STUB]           = new LogContainer("GDB_STUB",          "GDB Stub");
+    //m_Log[LogTypes::AUDIO_INTERFACE]    = new LogContainer("AI",                "AudioInt");
     m_Log[LogTypes::ARM11]              = new LogContainer("ARM11",             "ARM11");
     m_Log[LogTypes::OSHLE]              = new LogContainer("HLE",               "HLE");
-    m_Log[LogTypes::DSPHLE]             = new LogContainer("DSPHLE",            "DSP HLE");
-    m_Log[LogTypes::DSPLLE]             = new LogContainer("DSPLLE",            "DSP LLE");
-    m_Log[LogTypes::DSP_MAIL]           = new LogContainer("DSPMails",          "DSP Mails");
+    //m_Log[LogTypes::DSPHLE]             = new LogContainer("DSPHLE",            "DSP HLE");
+    //m_Log[LogTypes::DSPLLE]             = new LogContainer("DSPLLE",            "DSP LLE");
+    //m_Log[LogTypes::DSP_MAIL]           = new LogContainer("DSPMails",          "DSP Mails");
     m_Log[LogTypes::VIDEO]              = new LogContainer("Video",             "Video Backend");
-    m_Log[LogTypes::AUDIO]              = new LogContainer("Audio",             "Audio Emulator");
-    m_Log[LogTypes::DYNA_REC]           = new LogContainer("JIT",               "JIT");
-    m_Log[LogTypes::CONSOLE]            = new LogContainer("CONSOLE",           "Dolphin Console");
-    m_Log[LogTypes::OSREPORT]           = new LogContainer("OSREPORT",          "OSReport");
+    //m_Log[LogTypes::AUDIO]              = new LogContainer("Audio",             "Audio Emulator");
+    //m_Log[LogTypes::DYNA_REC]           = new LogContainer("JIT",               "JIT");
+    //m_Log[LogTypes::CONSOLE]            = new LogContainer("CONSOLE",           "Dolphin Console");
+    //m_Log[LogTypes::OSREPORT]           = new LogContainer("OSREPORT",          "OSReport");
     m_Log[LogTypes::TIME]               = new LogContainer("Time",              "Core Timing");
     m_Log[LogTypes::LOADER]             = new LogContainer("Loader",            "Loader");
     m_Log[LogTypes::FILESYS]            = new LogContainer("FileSys",           "File System");
-    m_Log[LogTypes::WII_IPC_HID]        = new LogContainer("WII_IPC_HID",       "WII IPC HID");
+    //m_Log[LogTypes::WII_IPC_HID]        = new LogContainer("WII_IPC_HID",       "WII IPC HID");
     m_Log[LogTypes::KERNEL]             = new LogContainer("KERNEL",            "KERNEL HLE");
-    m_Log[LogTypes::WII_IPC_DVD]        = new LogContainer("WII_IPC_DVD",       "WII IPC DVD");
-    m_Log[LogTypes::WII_IPC_ES]         = new LogContainer("WII_IPC_ES",        "WII IPC ES");
-    m_Log[LogTypes::WII_IPC_FILEIO]     = new LogContainer("WII_IPC_FILEIO",    "WII IPC FILEIO");
+    //m_Log[LogTypes::WII_IPC_DVD]        = new LogContainer("WII_IPC_DVD",       "WII IPC DVD");
+    //m_Log[LogTypes::WII_IPC_ES]         = new LogContainer("WII_IPC_ES",        "WII IPC ES");
+    //m_Log[LogTypes::WII_IPC_FILEIO]     = new LogContainer("WII_IPC_FILEIO",    "WII IPC FILEIO");
     m_Log[LogTypes::RENDER]             = new LogContainer("RENDER",            "RENDER");
     m_Log[LogTypes::GPU]                = new LogContainer("GPU",               "GPU");
     m_Log[LogTypes::SVC]                = new LogContainer("SVC",               "Supervisor Call HLE");
     m_Log[LogTypes::HLE]                = new LogContainer("HLE",               "High Level Emulation");
     m_Log[LogTypes::HW]                 = new LogContainer("HW",                "Hardware");
-    m_Log[LogTypes::ACTIONREPLAY]       = new LogContainer("ActionReplay",      "ActionReplay");
-    m_Log[LogTypes::MEMCARD_MANAGER]    = new LogContainer("MemCard Manager",   "MemCard Manager");
-    m_Log[LogTypes::NETPLAY]            = new LogContainer("NETPLAY",           "Netplay");
+    //m_Log[LogTypes::ACTIONREPLAY]       = new LogContainer("ActionReplay",      "ActionReplay");
+    //m_Log[LogTypes::MEMCARD_MANAGER]    = new LogContainer("MemCard Manager",   "MemCard Manager");
+    //m_Log[LogTypes::NETPLAY]            = new LogContainer("NETPLAY",           "Netplay");
     m_Log[LogTypes::GUI]                = new LogContainer("GUI",               "GUI");
 
     m_fileLog = new FileLogListener(FileUtil::GetUserPath(F_MAINLOG_IDX).c_str());
diff --git a/src/common/logging/backend.cpp b/src/common/logging/backend.cpp
new file mode 100644
index 000000000..e79b84604
--- /dev/null
+++ b/src/common/logging/backend.cpp
@@ -0,0 +1,151 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include <algorithm>
+
+#include "common/log.h" // For _dbg_assert_
+
+#include "common/logging/backend.h"
+#include "common/logging/log.h"
+#include "common/logging/text_formatter.h"
+
+namespace Log {
+
+static std::shared_ptr<Logger> global_logger;
+
+/// Macro listing all log classes. Code should define CLS and SUB as desired before invoking this.
+#define ALL_LOG_CLASSES() \
+        CLS(Log) \
+        CLS(Common) \
+        SUB(Common, Filesystem) \
+        SUB(Common, Memory) \
+        CLS(Core) \
+        SUB(Core, ARM11) \
+        CLS(Config) \
+        CLS(Debug) \
+        SUB(Debug, Emulated) \
+        SUB(Debug, GPU) \
+        SUB(Debug, Breakpoint) \
+        CLS(Kernel) \
+        SUB(Kernel, SVC) \
+        CLS(Service) \
+        SUB(Service, SRV) \
+        SUB(Service, FS) \
+        SUB(Service, APT) \
+        SUB(Service, GSP) \
+        SUB(Service, AC) \
+        SUB(Service, PTM) \
+        SUB(Service, CFG) \
+        SUB(Service, DSP) \
+        SUB(Service, HID) \
+        CLS(HW) \
+        SUB(HW, Memory) \
+        SUB(HW, GPU) \
+        CLS(Frontend) \
+        CLS(Render) \
+        SUB(Render, Software) \
+        SUB(Render, OpenGL) \
+        CLS(Loader)
+
+Logger::Logger() {
+    // Register logging classes so that they can be queried at runtime
+    size_t parent_class;
+    all_classes.reserve((size_t)Class::Count);
+
+#define CLS(x) \
+        all_classes.push_back(Class::x); \
+        parent_class = all_classes.size() - 1;
+#define SUB(x, y) \
+        all_classes.push_back(Class::x##_##y); \
+        all_classes[parent_class].num_children += 1;
+
+    ALL_LOG_CLASSES()
+#undef CLS
+#undef SUB
+
+    // Ensures that ALL_LOG_CLASSES isn't missing any entries.
+    _dbg_assert_(Log, all_classes.size() == (size_t)Class::Count);
+}
+
+// GetClassName is a macro defined by Windows.h, grrr...
+const char* Logger::GetLogClassName(Class log_class) {
+    switch (log_class) {
+#define CLS(x) case Class::x: return #x;
+#define SUB(x, y) case Class::x##_##y: return #x "." #y;
+        ALL_LOG_CLASSES()
+#undef CLS
+#undef SUB
+    }
+    return "Unknown";
+}
+
+const char* Logger::GetLevelName(Level log_level) {
+#define LVL(x) case Level::x: return #x
+    switch (log_level) {
+        LVL(Trace);
+        LVL(Debug);
+        LVL(Info);
+        LVL(Warning);
+        LVL(Error);
+        LVL(Critical);
+    }
+    return "Unknown";
+#undef LVL
+}
+
+void Logger::LogMessage(Entry entry) {
+    ring_buffer.Push(std::move(entry));
+}
+
+size_t Logger::GetEntries(Entry* out_buffer, size_t buffer_len) {
+    return ring_buffer.BlockingPop(out_buffer, buffer_len);
+}
+
+std::shared_ptr<Logger> InitGlobalLogger() {
+    global_logger = std::make_shared<Logger>();
+    return global_logger;
+}
+
+Entry CreateEntry(Class log_class, Level log_level,
+                        const char* filename, unsigned int line_nr, const char* function,
+                        const char* format, va_list args) {
+    using std::chrono::steady_clock;
+    using std::chrono::duration_cast;
+
+    static steady_clock::time_point time_origin = steady_clock::now();
+
+    std::array<char, 4 * 1024> formatting_buffer;
+
+    Entry entry;
+    entry.timestamp = duration_cast<std::chrono::microseconds>(steady_clock::now() - time_origin);
+    entry.log_class = log_class;
+    entry.log_level = log_level;
+
+    snprintf(formatting_buffer.data(), formatting_buffer.size(), "%s:%s:%u", filename, function, line_nr);
+    entry.location = std::string(formatting_buffer.data());
+
+    vsnprintf(formatting_buffer.data(), formatting_buffer.size(), format, args);
+    entry.message = std::string(formatting_buffer.data());
+
+    return std::move(entry);
+}
+
+void LogMessage(Class log_class, Level log_level,
+                const char* filename, unsigned int line_nr, const char* function,
+                const char* format, ...) {
+    va_list args;
+    va_start(args, format);
+    Entry entry = CreateEntry(log_class, log_level,
+            filename, line_nr, function, format, args);
+    va_end(args);
+
+    if (global_logger != nullptr && !global_logger->IsClosed()) {
+        global_logger->LogMessage(std::move(entry));
+    } else {
+        // Fall back to directly printing to stderr
+        PrintMessage(entry);
+    }
+}
+
+}
diff --git a/src/common/logging/backend.h b/src/common/logging/backend.h
new file mode 100644
index 000000000..ae270efe8
--- /dev/null
+++ b/src/common/logging/backend.h
@@ -0,0 +1,134 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <cstdarg>
+#include <memory>
+#include <vector>
+
+#include "common/concurrent_ring_buffer.h"
+
+#include "common/logging/log.h"
+
+namespace Log {
+
+/**
+ * A log entry. Log entries are store in a structured format to permit more varied output
+ * formatting on different frontends, as well as facilitating filtering and aggregation.
+ */
+struct Entry {
+    std::chrono::microseconds timestamp;
+    Class log_class;
+    Level log_level;
+    std::string location;
+    std::string message;
+
+    Entry() = default;
+
+    // TODO(yuriks) Use defaulted move constructors once MSVC supports them
+#define MOVE(member) member(std::move(o.member))
+    Entry(Entry&& o)
+        : MOVE(timestamp), MOVE(log_class), MOVE(log_level),
+        MOVE(location), MOVE(message)
+    {}
+#undef MOVE
+
+    Entry& operator=(const Entry&& o) {
+#define MOVE(member) member = std::move(o.member)
+        MOVE(timestamp);
+        MOVE(log_class);
+        MOVE(log_level);
+        MOVE(location);
+        MOVE(message);
+#undef MOVE
+        return *this;
+    }
+};
+
+struct ClassInfo {
+    Class log_class;
+
+    /**
+        * Total number of (direct or indirect) sub classes this class has. If any, they follow in
+        * sequence after this class in the class list.
+        */
+    unsigned int num_children = 0;
+
+    ClassInfo(Class log_class) : log_class(log_class) {}
+};
+
+/**
+ * Logging management class. This class has the dual purpose of acting as an exchange point between
+ * the logging clients and the log outputter, as well as containing reflection info about available
+ * log classes.
+ */
+class Logger {
+private:
+    using Buffer = Common::ConcurrentRingBuffer<Entry, 16 * 1024 / sizeof(Entry)>;
+
+public:
+    static const size_t QUEUE_CLOSED = Buffer::QUEUE_CLOSED;
+
+    Logger();
+
+    /**
+     * Returns a list of all vector classes and subclasses. The sequence returned is a pre-order of
+     * classes and subclasses, which together with the `num_children` field in ClassInfo, allows
+     * you to recover the hierarchy.
+     */
+    const std::vector<ClassInfo>& GetClasses() const { return all_classes; }
+
+    /**
+     * Returns the name of the passed log class as a C-string. Subclasses are separated by periods
+     * instead of underscores as in the enumeration.
+     */
+    static const char* GetLogClassName(Class log_class);
+
+    /**
+     * Returns the name of the passed log level as a C-string.
+     */
+    static const char* GetLevelName(Level log_level);
+
+    /**
+     * Appends a messages to the log buffer.
+     * @note This function is thread safe.
+     */
+    void LogMessage(Entry entry);
+
+    /**
+     * Retrieves a batch of messages from the log buffer, blocking until they are available.
+     * @note This function is thread safe.
+     *
+     * @param out_buffer Destination buffer that will receive the log entries.
+     * @param buffer_len The maximum size of `out_buffer`.
+     * @return The number of entries stored. In case the logger is shutting down, `QUEUE_CLOSED` is
+     *         returned, no entries are stored and the logger should shutdown.
+     */
+    size_t GetEntries(Entry* out_buffer, size_t buffer_len);
+
+    /**
+     * Initiates a shutdown of the logger. This will indicate to log output clients that they
+     * should shutdown.
+     */
+    void Close() { ring_buffer.Close(); }
+
+    /**
+     * Returns true if Close() has already been called on the Logger.
+     */
+    bool IsClosed() const { return ring_buffer.IsClosed(); }
+
+private:
+    Buffer ring_buffer;
+    std::vector<ClassInfo> all_classes;
+};
+
+/// Creates a log entry by formatting the given source location, and message.
+Entry CreateEntry(Class log_class, Level log_level,
+                        const char* filename, unsigned int line_nr, const char* function,
+                        const char* format, va_list args);
+/// Initializes the default Logger.
+std::shared_ptr<Logger> InitGlobalLogger();
+
+}
diff --git a/src/common/logging/log.h b/src/common/logging/log.h
new file mode 100644
index 000000000..1eec34fbb
--- /dev/null
+++ b/src/common/logging/log.h
@@ -0,0 +1,115 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <cassert>
+#include <chrono>
+#include <string>
+
+#include "common/common_types.h"
+
+namespace Log {
+
+/// Specifies the severity or level of detail of the log message.
+enum class Level : u8 {
+    Trace,    ///< Extremely detailed and repetitive debugging information that is likely to
+              ///  pollute logs.
+    Debug,    ///< Less detailed debugging information.
+    Info,     ///< Status information from important points during execution.
+    Warning,  ///< Minor or potential problems found during execution of a task.
+    Error,    ///< Major problems found during execution of a task that prevent it from being
+              ///  completed.
+    Critical, ///< Major problems during execution that threathen the stability of the entire
+              ///  application.
+
+    Count ///< Total number of logging levels
+};
+
+typedef u8 ClassType;
+
+/**
+ * Specifies the sub-system that generated the log message.
+ *
+ * @note If you add a new entry here, also add a corresponding one to `ALL_LOG_CLASSES` in log.cpp.
+ */
+enum class Class : ClassType {
+    Log,                        ///< Messages about the log system itself
+    Common,                     ///< Library routines
+    Common_Filesystem,          ///< Filesystem interface library
+    Common_Memory,              ///< Memory mapping and management functions
+    Core,                       ///< LLE emulation core
+    Core_ARM11,                 ///< ARM11 CPU core
+    Config,                     ///< Emulator configuration (including commandline)
+    Debug,                      ///< Debugging tools
+    Debug_Emulated,             ///< Debug messages from the emulated programs
+    Debug_GPU,                  ///< GPU debugging tools
+    Debug_Breakpoint,           ///< Logging breakpoints and watchpoints
+    Kernel,                     ///< The HLE implementation of the CTR kernel
+    Kernel_SVC,                 ///< Kernel system calls
+    Service,                    ///< HLE implementation of system services. Each major service
+                                ///  should have its own subclass.
+    Service_SRV,                ///< The SRV (Service Directory) implementation
+    Service_FS,                 ///< The FS (Filesystem) service implementation
+    Service_APT,                ///< The APT (Applets) service
+    Service_GSP,                ///< The GSP (GPU control) service
+    Service_AC,                 ///< The AC (WiFi status) service
+    Service_PTM,                ///< The PTM (Power status & misc.) service
+    Service_CFG,                ///< The CFG (Configuration) service
+    Service_DSP,                ///< The DSP (DSP control) service
+    Service_HID,                ///< The HID (User input) service
+    HW,                         ///< Low-level hardware emulation
+    HW_Memory,                  ///< Memory-map and address translation
+    HW_GPU,                     ///< GPU control emulation
+    Frontend,                   ///< Emulator UI
+    Render,                     ///< Emulator video output and hardware acceleration
+    Render_Software,            ///< Software renderer backend
+    Render_OpenGL,              ///< OpenGL backend
+    Loader,                     ///< ROM loader
+
+    Count ///< Total number of logging classes
+};
+
+/**
+ * Level below which messages are simply discarded without buffering regardless of the display
+ * settings.
+ */
+const Level MINIMUM_LEVEL =
+#ifdef _DEBUG
+    Level::Trace;
+#else
+    Level::Debug;
+#endif
+
+/**
+ * Logs a message to the global logger. This proxy exists to avoid exposing the details of the
+ * Logger class, including the ConcurrentRingBuffer template, to all files that desire to log
+ * messages, reducing unecessary recompilations.
+ */
+void LogMessage(Class log_class, Level log_level,
+    const char* filename, unsigned int line_nr, const char* function,
+#ifdef _MSC_VER
+    _Printf_format_string_
+#endif
+    const char* format, ...)
+#ifdef __GNUC__
+    __attribute__((format(printf, 6, 7)))
+#endif
+    ;
+
+} // namespace Log
+
+#define LOG_GENERIC(log_class, log_level, ...) \
+    do { \
+        if (::Log::Level::log_level >= ::Log::MINIMUM_LEVEL) \
+            ::Log::LogMessage(::Log::Class::log_class, ::Log::Level::log_level, \
+                       __FILE__, __LINE__, __func__, __VA_ARGS__); \
+    } while (0)
+
+#define LOG_TRACE(   log_class, ...) LOG_GENERIC(log_class, Trace,    __VA_ARGS__)
+#define LOG_DEBUG(   log_class, ...) LOG_GENERIC(log_class, Debug,    __VA_ARGS__)
+#define LOG_INFO(    log_class, ...) LOG_GENERIC(log_class, Info,     __VA_ARGS__)
+#define LOG_WARNING( log_class, ...) LOG_GENERIC(log_class, Warning,  __VA_ARGS__)
+#define LOG_ERROR(   log_class, ...) LOG_GENERIC(log_class, Error,    __VA_ARGS__)
+#define LOG_CRITICAL(log_class, ...) LOG_GENERIC(log_class, Critical, __VA_ARGS__)
diff --git a/src/common/logging/text_formatter.cpp b/src/common/logging/text_formatter.cpp
new file mode 100644
index 000000000..01c355bb6
--- /dev/null
+++ b/src/common/logging/text_formatter.cpp
@@ -0,0 +1,47 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include <array>
+#include <cstdio>
+
+#include "common/logging/backend.h"
+#include "common/logging/log.h"
+#include "common/logging/text_formatter.h"
+
+namespace Log {
+
+void FormatLogMessage(const Entry& entry, char* out_text, size_t text_len) {
+    unsigned int time_seconds    = static_cast<unsigned int>(entry.timestamp.count() / 1000000);
+    unsigned int time_fractional = static_cast<unsigned int>(entry.timestamp.count() % 1000000);
+
+    const char* class_name = Logger::GetLogClassName(entry.log_class);
+    const char* level_name = Logger::GetLevelName(entry.log_level);
+
+    snprintf(out_text, text_len, "[%4u.%06u] %s <%s> %s: %s",
+        time_seconds, time_fractional, class_name, level_name,
+        entry.location.c_str(), entry.message.c_str());
+}
+
+void PrintMessage(const Entry& entry) {
+    std::array<char, 4 * 1024> format_buffer;
+    FormatLogMessage(entry, format_buffer.data(), format_buffer.size());
+    fputs(format_buffer.data(), stderr);
+    fputc('\n', stderr);
+}
+
+void TextLoggingLoop(std::shared_ptr<Logger> logger) {
+    std::array<Entry, 256> entry_buffer;
+
+    while (true) {
+        size_t num_entries = logger->GetEntries(entry_buffer.data(), entry_buffer.size());
+        if (num_entries == Logger::QUEUE_CLOSED) {
+            break;
+        }
+        for (size_t i = 0; i < num_entries; ++i) {
+            PrintMessage(entry_buffer[i]);
+        }
+    }
+}
+
+}
diff --git a/src/common/logging/text_formatter.h b/src/common/logging/text_formatter.h
new file mode 100644
index 000000000..6c2a6f1ea
--- /dev/null
+++ b/src/common/logging/text_formatter.h
@@ -0,0 +1,26 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <cstddef>
+#include <memory>
+
+namespace Log {
+
+class Logger;
+struct Entry;
+
+/// Formats a log entry into the provided text buffer.
+void FormatLogMessage(const Entry& entry, char* out_text, size_t text_len);
+/// Formats and prints a log entry to stderr.
+void PrintMessage(const Entry& entry);
+
+/**
+ * Logging loop that repeatedly reads messages from the provided logger and prints them to the
+ * console. It is the baseline barebones log outputter.
+ */
+void TextLoggingLoop(std::shared_ptr<Logger> logger);
+
+}
diff --git a/src/common/thread.h b/src/common/thread.h
index be9b5cbe2..8c36d3f07 100644
--- a/src/common/thread.h
+++ b/src/common/thread.h
@@ -21,6 +21,7 @@
 //for gettimeofday and struct time(spec|val)
 #include <time.h>
 #include <sys/time.h>
+#include <unistd.h>
 #endif
 
 namespace Common
diff --git a/src/core/hle/config_mem.cpp b/src/core/hle/config_mem.cpp
index c7cf5b1d3..1c9b89227 100644
--- a/src/core/hle/config_mem.cpp
+++ b/src/core/hle/config_mem.cpp
@@ -3,6 +3,7 @@
 // Refer to the license.txt file included.
 
 #include "common/common_types.h"
+#include "common/log.h"
 
 #include "core/hle/config_mem.h"