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/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();
+}