Monitor all HID++ reports on wireless device 1

Again, many things were done in this commit such as implementing an
I/O queue, a mutex_queue, and implementing the hidpp::Report class.

I'm expecting commits to be like this until I can get a clean
codebase for the backend.

src/logid/CMakeLists.txt

@@ -12,11 +12,13 @@ add_executable(logid
         logid.cpp
         util.cpp
         DeviceMonitor.cpp
+        backend/Error.cpp
         backend/raw/DeviceMonitor.cpp
         backend/raw/RawDevice.cpp
         backend/hidpp/Device.cpp
         backend/hidpp/Report.cpp
-        backend/dj/Report.cpp)
+        backend/dj/Report.cpp
+        util/mutex_queue.h)
 
 set_target_properties(logid PROPERTIES RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR})
 

src/logid/DeviceMonitor.cpp

@@ -102,9 +102,29 @@ void DeviceMonitor::stopAndDeleteDevice (const std::string &path, HIDPP::DeviceI
 void DeviceMonitor::addDevice(std::string path)
 {
     try {
-        backend::hidpp::Device device(path, hidpp::DeviceIndex::DefaultDevice);
+        backend::hidpp::Device device(path, hidpp::DeviceIndex::WirelessDevice1);
-
         log_printf(DEBUG, "Detected HID++ device at %s", path.c_str());
+
+        backend::hidpp::EventHandler eventHandler;
+        eventHandler.condition = [device](backend::hidpp::Report& report)->bool
+        {
+            return true;
+        };
+        eventHandler.callback = [device](backend::hidpp::Report& report)->void
+        {
+            log_printf(DEBUG, "Event on %s:%d", device.devicePath().c_str(),
+                    device.deviceIndex());
+            for(auto& i : report.rawReport())
+                    printf("%02x ", i);
+            printf("\n");
+        };
+
+        device.addEventHandler("MONITOR_ALL", eventHandler);
+
+        std::thread([](backend::hidpp::Device device) { device.listen(); }, device).detach();
+
+        /* This is a temporary solution to avoid std::bad_function_call */
+        while(true) {}
     }
     catch(backend::hidpp::Device::InvalidDevice &e)
     {

src/logid/DeviceMonitor.h

@@ -38,6 +38,7 @@ namespace logid
     private:
     	std::mutex devices_mutex;
         std::map<std::string, std::map<backend::hidpp::DeviceIndex, ConnectedDevice>> devices;
+        backend::hidpp::EventHandler eventHandler;
     };
 
     extern DeviceMonitor* finder;

src/logid/backend/Error.cpp

@@ -0,0 +1,6 @@
+#include "Error.h"
+
+const char *logid::backend::TimeoutError::what() noexcept
+{
+    return "Device timed out";
+}

src/logid/backend/Error.h

@@ -0,0 +1,16 @@
+#ifndef LOGID_BACKEND_ERROR_H
+#define LOGID_BACKEND_ERROR_H
+
+#include <stdexcept>
+
+namespace logid {
+namespace backend {
+class TimeoutError: public std::exception
+{
+public:
+    TimeoutError() = default;
+    virtual const char* what() noexcept;
+};
+}}
+
+#endif //LOGID_BACKEND_ERROR_H

src/logid/backend/defs.h

@@ -0,0 +1,15 @@
+#ifndef LOGID_BACKEND_DEFS_H
+#define LOGID_BACKEND_DEFS_H
+
+#include <functional>
+
+namespace logid::backend
+{
+    struct RawEventHandler
+    {
+        std::function<bool(std::vector<uint8_t>& )> condition;
+        std::function<void(std::vector<uint8_t>& )> callback;
+    };
+}
+
+#endif //LOGID_BACKEND_DEFS_H

src/logid/backend/hidpp/Device.cpp

@@ -1,3 +1,4 @@
+#include <assert.h>
 #include "Device.h"
 #include "Report.h"
 
@@ -21,10 +22,67 @@ Device::InvalidDevice::Reason Device::InvalidDevice::code() const noexcept
 }
 
 /// TODO: Initialize a single RawDevice for each path.
-Device::Device(std::string path, DeviceIndex index):
+Device::Device(const std::string& path, DeviceIndex index):
     raw_device (std::make_shared<raw::RawDevice>(path)), path (path), index (index)
 {
     supported_reports = getSupportedReports(raw_device->reportDescriptor());
     if(!supported_reports)
         throw InvalidDevice(InvalidDevice::NoHIDPPReport);
-}
+
+    // Pass all HID++ events with device index to this device.
+    RawEventHandler rawEventHandler;
+    rawEventHandler.condition = [index](std::vector<uint8_t>& report)->bool
+    {
+        return (report[Offset::Type] == Report::Short ||
+            report[Offset::Type] == Report::Long) && (report[Offset::DeviceIndex] == index);
+    };
+    rawEventHandler.callback = [this](std::vector<uint8_t>& report)->void
+    {
+        Report _report(report);
+        this->handleEvent(_report);
+    };
+
+    raw_device->addEventHandler("DEV_" + std::to_string(index), rawEventHandler);
+}
+
+void Device::addEventHandler(const std::string& nickname, EventHandler& handler)
+{
+    auto it = event_handlers.find(nickname);
+    assert(it == event_handlers.end());
+
+    event_handlers.emplace(nickname, handler);
+}
+
+void Device::removeEventHandler(const std::string& nickname)
+{
+    event_handlers.erase(nickname);
+}
+
+void Device::handleEvent(Report& report)
+{
+    for(auto& handler : event_handlers)
+        if(handler.second.condition(report))
+            handler.second.callback(report);
+}
+
+Report Device::sendReport(Report& report)
+{
+    switch(report.type())
+    {
+        case Report::Short:
+            if(!(supported_reports & HIDPP_REPORT_SHORT_SUPPORTED))
+                report.setType(Report::Long);
+            break;
+        case Report::Long:
+            /* Report can be truncated, but that isn't a good idea. */
+            assert(supported_reports & HIDPP_REPORT_LONG_SUPPORTED);
+    }
+
+    auto raw_response = raw_device->sendReport(report.rawReport());
+    return Report(raw_response);
+}
+
+void Device::listen()
+{
+    raw_device->listen();
+}

src/logid/backend/hidpp/Device.h

@@ -3,22 +3,21 @@
 
 #include <string>
 #include <memory>
+#include <functional>
+#include <map>
 #include "../raw/RawDevice.h"
+#include "Report.h"
+#include "defs.h"
 
-namespace logid::backend::hidpp
+namespace logid {
+namespace backend {
+namespace hidpp
 {
-    enum DeviceIndex: uint8_t
+    struct EventHandler
     {
-        DefaultDevice = 0,
+        std::function<bool(Report&)> condition;
-        WirelessDevice1 = 1,
+        std::function<void(Report&)> callback;
-        WirelessDevice2 = 2,
-        WirelessDevice3 = 3,
-        WirelessDevice4 = 4,
-        WirelessDevice5 = 5,
-        WirelessDevice6 = 6,
-        CordedDevice = 0xff
     };
-
     class Device
     {
     public:
@@ -35,17 +34,30 @@ namespace logid::backend::hidpp
             virtual Reason code() const noexcept;
         private:
             Reason _reason;
-
         };
-        Device(std::string path, DeviceIndex index);
+
+        Device(const std::string& path, DeviceIndex index);
+
         std::string devicePath() const { return path; }
         DeviceIndex deviceIndex() const { return index; }
+
+        void listen(); // Runs asynchronously
+        void stopListening();
+
+        void addEventHandler(const std::string& nickname, EventHandler& handler);
+        void removeEventHandler(const std::string& nickname);
+
+        Report sendReport(Report& report);
+
+        void handleEvent(Report& report);
     private:
-        std::shared_ptr<logid::backend::raw::RawDevice> raw_device;
+        std::shared_ptr<raw::RawDevice> raw_device;
         std::string path;
         DeviceIndex index;
         uint8_t supported_reports;
+
+        std::map<std::string, EventHandler> event_handlers;
     };
-}
+} } }
 
 #endif //LOGID_HIDPP_DEVICE_H

src/logid/backend/hidpp/Report.cpp

@@ -1,5 +1,6 @@
 #include <array>
 #include <algorithm>
+#include <cassert>
 #include "Report.h"
 
 using namespace logid::backend::hidpp;
@@ -80,4 +81,80 @@ uint8_t hidpp::getSupportedReports(std::vector<uint8_t>&& rdesc)
         ret |= HIDPP_REPORT_LONG_SUPPORTED;
 
     return ret;
-}
+}
+
+const char *Report::InvalidReportID::what() const noexcept
+{
+    return "Invalid report ID";
+}
+
+const char *Report::InvalidReportLength::what() const noexcept
+{
+    return "Invalid report length";
+}
+
+Report::Report(Report::Type type, DeviceIndex device_index,
+        uint8_t feature_index, uint8_t function, uint8_t sw_id)
+{
+    assert(!(function & functionMask));
+    assert(!(sw_id & swIdMask));
+
+    switch(type)
+    {
+        case Short:
+            _data.resize(HeaderLength + ShortParamLength);
+            break;
+        case Long:
+            _data.resize(HeaderLength + LongParamLength);
+            break;
+        default:
+            throw InvalidReportID();
+    }
+
+    _data[Offset::Type] = type;
+    _data[Offset::DeviceIndex] = device_index;
+    _data[Offset::Feature] = feature_index;
+    _data[Offset::Function] = (function & functionMask) << 4 | (sw_id & swIdMask);
+}
+
+Report::Report(const std::vector<uint8_t>& data)
+{
+    _data = data;
+
+    switch(_data[Offset::Type])
+    {
+        case Short:
+            _data.resize(HeaderLength + ShortParamLength);
+            break;
+        case Long:
+            _data.resize(HeaderLength + LongParamLength);
+            break;
+        default:
+            throw InvalidReportID();
+    }
+}
+
+void Report::setType(Report::Type type)
+{
+    switch(type)
+    {
+        case Short:
+            _data.resize(HeaderLength + ShortParamLength);
+            break;
+        case Long:
+            _data.resize(HeaderLength + LongParamLength);
+            break;
+        default:
+            throw InvalidReportID();
+    }
+
+    _data[Offset::Type] = type;
+}
+
+void Report::setParams(const std::vector<uint8_t>& _params)
+{
+    assert(_params.size() <= _data.size()-HeaderLength);
+
+    for(std::size_t i = 0; i < _params.size(); i++)
+        _data[Offset::Parameters + i] = _params[i];
+}

src/logid/backend/hidpp/Report.h

@@ -3,9 +3,7 @@
 
 #include <cstdint>
 #include "../raw/RawDevice.h"
-#include "Device.h"
+#include "defs.h"
-
-#define LOGID_HIDPP_SW_ID 0x0f
 
 /* Some devices only support a subset of these reports */
 #define HIDPP_REPORT_SHORT_SUPPORTED      1U
@@ -15,6 +13,16 @@
 namespace logid::backend::hidpp
 {
     uint8_t getSupportedReports(std::vector<uint8_t>&& rdesc);
+
+    namespace Offset
+    {
+        static constexpr uint8_t Type = 0;
+        static constexpr uint8_t DeviceIndex = 1;
+        static constexpr uint8_t Feature = 2;
+        static constexpr uint8_t Function = 3;
+        static constexpr uint8_t Parameters = 4;
+    }
+
     class Report
     {
     public:
@@ -24,30 +32,43 @@ namespace logid::backend::hidpp
             Long = 0x11
         };
 
-        class InvalidReportID: std::exception
+        class InvalidReportID: public std::exception
         {
-            InvalidReportID();
+        public:
+            InvalidReportID() = default;
             virtual const char* what() const noexcept;
         };
 
-        class InvalidReportLength: std::exception
+        class InvalidReportLength: public std::exception
         {
-            InvalidReportLength();
+        public:
+            InvalidReportLength() = default;;
             virtual const char* what() const noexcept;
         };
 
-        static constexpr std::size_t MaxDataLength = 32;
+        static constexpr std::size_t MaxDataLength = 20;
+        static constexpr uint8_t swIdMask = 0x0f;
+        static constexpr uint8_t functionMask = 0x0f;
 
-        Report(uint8_t report_id, const uint8_t* data, std::size_t length);
+        Report(Type type, DeviceIndex device_index,
-        Report(std::vector<uint8_t> data);
+                uint8_t feature_index,
+                uint8_t function,
+                uint8_t sw_id);
+        explicit Report(const std::vector<uint8_t>& data);
 
-        Type type() const;
+        Type type() const { return static_cast<Type>(_data[Offset::Type]); };
         void setType(Report::Type type);
 
-        logid::backend::hidpp::DeviceIndex deviceIndex();
+        std::vector<uint8_t>::const_iterator paramBegin() const { return _data.begin() + Offset::Parameters; }
+        std::vector<uint8_t>::const_iterator paramEnd() const { return _data.end(); }
+        void setParams(const std::vector<uint8_t>& _params);
+
+        logid::backend::hidpp::DeviceIndex deviceIndex()
+        {
+            return static_cast<DeviceIndex>(_data[Offset::DeviceIndex]);
+        }
 
         std::vector<uint8_t> rawReport () const { return _data; }
-
     private:
         static constexpr std::size_t HeaderLength = 4;
         std::vector<uint8_t> _data;

src/logid/backend/hidpp/defs.h

@@ -0,0 +1,24 @@
+#ifndef LOGID_HIDPP_DEFS_H
+#define LOGID_HIDPP_DEFS_H
+
+#define LOGID_HIDPP_SOFTWARE_ID 1
+
+namespace logid::backend::hidpp
+{
+    enum DeviceIndex: uint8_t
+    {
+        DefaultDevice = 0,
+        WirelessDevice1 = 1,
+        WirelessDevice2 = 2,
+        WirelessDevice3 = 3,
+        WirelessDevice4 = 4,
+        WirelessDevice5 = 5,
+        WirelessDevice6 = 6,
+        CordedDevice = 0xff
+    };
+
+    static constexpr std::size_t ShortParamLength = 3;
+    static constexpr std::size_t LongParamLength = 16;
+}
+
+#endif //LOGID_HIDPP_DEFS_H

src/logid/backend/raw/RawDevice.cpp

@@ -1,9 +1,11 @@
 #include "RawDevice.h"
+#include "../Error.h"
 
 #include <string>
 #include <system_error>
-#include <utility>
+#include <cassert>
 
+#define MAX_DATA_LENGTH 32
 
 extern "C"
 {
@@ -76,29 +78,43 @@ RawDevice::~RawDevice()
     }
 }
 
-void RawDevice::sendReport(std::vector<uint8_t> report)
+std::vector<uint8_t> RawDevice::sendReport(const std::vector<uint8_t>& report)
 {
-    _sendReport(std::move(report));
+    std::packaged_task<std::vector<uint8_t>()> task(
+            [=]() {
+        _sendReport(report);
+        std::vector<uint8_t> response;
+        _readReport(response, MAX_DATA_LENGTH);
+        return response;
+    });
+
+    /* If the listener will stop, handle I/O manually.
+     * Otherwise, push to queue and wait for result. */
+    if(continue_listen)
+    {
+        auto f = task.get_future();
+        write_queue.push(&task);
+        return f.get();
+    }
+    else
+        return task.get_future().get();
 }
 
-std::vector<uint8_t> RawDevice::readReport(std::size_t maxDataLength)
+int RawDevice::_sendReport(const std::vector<uint8_t>& report)
-{
-    return _readReport(maxDataLength);
-}
-
-void RawDevice::_sendReport(std::vector<uint8_t> report)
 {
     std::lock_guard<std::mutex> lock(dev_io);
     int ret = ::write(fd, report.data(), report.size());
     if(ret == -1)
         throw std::system_error(errno, std::system_category(), "_sendReport write failed");
+
+    return ret;
 }
 
-std::vector<uint8_t> RawDevice::_readReport(std::size_t maxDataLength)
+int RawDevice::_readReport(std::vector<uint8_t>& report, std::size_t maxDataLength)
 {
     std::lock_guard<std::mutex> lock(dev_io);
     int ret;
-    std::vector<uint8_t> report(maxDataLength);
+    report.resize(maxDataLength);
 
     timeval timeout = { duration_cast<milliseconds>(HIDPP_IO_TIMEOUT).count(),
                        duration_cast<microseconds>(HIDPP_IO_TIMEOUT).count() };
@@ -133,7 +149,10 @@ std::vector<uint8_t> RawDevice::_readReport(std::size_t maxDataLength)
             throw std::system_error(errno, std::system_category(), "_readReport read pipe failed");
     }
 
-    return report;
+    if(0 == ret)
+        throw backend::TimeoutError();
+
+    return ret;
 }
 
 void RawDevice::interruptRead()
@@ -144,4 +163,62 @@ void RawDevice::interruptRead()
 
     // Ensure I/O has halted
     std::lock_guard<std::mutex> lock(dev_io);
-}
+}
+
+void RawDevice::listen()
+{
+    std::lock_guard<std::mutex> lock(listening);
+
+    continue_listen = true;
+    while(continue_listen)
+    {
+        while(!write_queue.empty())
+        {
+            auto task = write_queue.front();
+            (*task)();
+            write_queue.pop();
+        }
+        std::vector<uint8_t> report;
+        _readReport(report, MAX_DATA_LENGTH);
+        std::thread([this](std::vector<uint8_t> report) {
+            this->handleEvent(report);
+        }, report).detach();
+    }
+
+    continue_listen = false;
+}
+
+void RawDevice::stopListener()
+{
+    continue_listen = false;
+    interruptRead();
+}
+
+void RawDevice::addEventHandler(const std::string &nickname, RawEventHandler &handler)
+{
+    auto it = event_handlers.find(nickname);
+    assert(it == event_handlers.end());
+    event_handlers.emplace(nickname, handler);
+}
+
+void RawDevice::removeEventHandler(const std::string &nickname)
+{
+    event_handlers.erase(nickname);
+}
+
+void RawDevice::handleEvent(std::vector<uint8_t> &report)
+{
+    for(auto& handler : event_handlers)
+        if(handler.second.condition(report))
+            handler.second.callback(report);
+}
+
+bool RawDevice::isListening()
+{
+    bool ret = listening.try_lock();
+
+    if(ret)
+        listening.unlock();
+
+    return ret;
+}

src/logid/backend/raw/RawDevice.h

@@ -4,10 +4,18 @@
 #include <string>
 #include <vector>
 #include <mutex>
+#include <map>
+#include <atomic>
+#include <future>
+
+#include "../defs.h"
+#include "../../util/mutex_queue.h"
 
 #define HIDPP_IO_TIMEOUT std::chrono::seconds(2)
 
-namespace logid::backend::raw
+namespace logid {
+namespace backend {
+namespace raw
 {
     class RawDevice
     {
@@ -18,12 +26,18 @@ namespace logid::backend::raw
         std::vector<uint8_t> reportDescriptor() const { return rdesc; }
 
         /// TODO: Process reports in a queue.
-        void sendReport(std::vector<uint8_t> report);
+        std::vector<uint8_t> sendReport(const std::vector<uint8_t>& report);
-        std::vector<uint8_t> readReport(std::size_t maxDataLength);
-
         void interruptRead();
+
+        void listen();
+        void stopListener();
+        bool isListening();
+
+        void addEventHandler(const std::string& nickname, RawEventHandler& handler);
+        void removeEventHandler(const std::string& nickname);
+
     private:
-        std::mutex dev_io;
+        std::mutex dev_io, listening;
         std::string path;
         int fd;
         int dev_pipe[2];
@@ -32,10 +46,17 @@ namespace logid::backend::raw
         std::string name;
         std::vector<uint8_t> rdesc;
 
+        std::atomic<bool> continue_listen;
+
+        std::map<std::string, backend::RawEventHandler> event_handlers;
+        void handleEvent(std::vector<uint8_t>& report);
+
         /* These will only be used internally and processed with a queue */
-        void _sendReport(std::vector<uint8_t> report);
+        int _sendReport(const std::vector<uint8_t>& report);
-        std::vector<uint8_t> _readReport(std::size_t maxDataLength);
+        int _readReport(std::vector<uint8_t>& report, std::size_t maxDataLength);
+
+        mutex_queue<std::packaged_task<std::vector<uint8_t>()>*> write_queue;
     };
-}
+}}}
 
 #endif //LOGID_BACKEND_RAWDEVICE_H

src/logid/util/mutex_queue.h

@@ -0,0 +1,37 @@
+#ifndef MUTEX_QUEUE_H
+#define MUTEX_QUEUE_H
+
+#include <queue>
+#include <mutex>
+
+template<typename data>
+class mutex_queue
+{
+public:
+    mutex_queue<data>() = default;
+    bool empty()
+    {
+        std::lock_guard<std::mutex> lock(_mutex);
+        return _queue.empty();
+    }
+    data& front()
+    {
+        std::lock_guard<std::mutex> lock(_mutex);
+        return _queue.front();
+    }
+    void push(const data& _data)
+    {
+        std::lock_guard<std::mutex> lock(_mutex);
+        _queue.push(_data);
+    }
+    void pop()
+    {
+        std::lock_guard<std::mutex> lock(_mutex);
+        _queue.pop();
+    }
+private:
+    std::queue<data> _queue;
+    std::mutex _mutex;
+};
+
+#endif //MUTEX_QUEUE_H