5 files changed, 473 insertions, 0 deletions

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);
+
+}