CANDeviceScanner.h

Go to the documentation of this file.

/*
 * Copyright (c) 2018-2026 REV Robotics
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of REV Robotics nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
 
#pragma once
 
#include <rev/driver/FRCCanSpec.h>
#include <stdint.h>
 
#include <atomic>
#include <map>
#include <memory>
#include <set>
#include <string>
#include <thread>
#include <unordered_map>
#include <utility>
#include <vector>
 
namespace rev {
namespace detail {
 
static const char* frc_deviceType_text[16] = {
    "Broadcast",          "Robot Controller",
    "Motor Controller",   "Relay Controller",
    "Gyro Sensor",        "Accelerometer",
    "Ultrasonic Sensor",  "Gear Tooth Sensor",
    "Power Distribution", "Pneumatics Controller",
    "Misc CAN Device",    "IO Breakout",
    "Servo Controller",   "Reserved",
    "Firmware Update",    "Unknown",
};
 
static inline const char* GetFRCDeviceTypeText(uint32_t index) {
    if (index > 12 && index < 31) {
        index = 13;
    } else if (index > 31) {
        index = 15;
    } else if (index == 31) {
        index = 14;
    } else {
        index = 0;
    }
    return frc_deviceType_text[index];
}
 
static const char* frc_manufacturer_text[18] = {"Broadcast",
                                                "NI",
                                                "LM",
                                                "DEKA",
                                                "CTRE",
                                                "REV",
                                                "Grapple",
                                                "MindSensors",
                                                "Team Use",
                                                "Kauai Labs",
                                                "Copperforge",
                                                "Playing with Fusion",
                                                "Studica",
                                                "TheThriftyBot",
                                                "Redux Robotics",
                                                "AndyMark",
                                                "Vivid-Hosting",
                                                "Unknown"};
 
static inline const char* GetFRCManufacturerText(uint32_t index) {
    index = (index > 17) ? 17 : index;
    return frc_manufacturer_text[index];
}
 
// Note: This is dependent on __attribute__((PACKED)) and processor is
// little-endian
 
#ifdef _WIN32
#define PACKED
#pragma pack(push, 1)
#else
#define PACKED __attribute__((__packed__))
#endif
 
struct PACKED frc_frameIDFields_t {
    uint16_t deviceNumber : 6;
    uint16_t api : 10;
    rev::FRCManufacturer manufacturer : 8;
    rev::FRCDeviceType deviceType : 5;
    uint8_t rsvd : 3;  // these are DNC
};
 
#ifdef _WIN32
#pragma pack(pop)
#endif
 
union frc_frameID_t {
    frc_frameIDFields_t fields;
    uint32_t raw;
};
 
struct CANScanIdentifier {
    rev::FRCDeviceType deviceTypeId;
    rev::FRCManufacturer manufacturerId;
    uint16_t canId;
    uint32_t uniqueId;
    std::string name;
    CANScanIdentifier(uint32_t arbid, std::string name, uint32_t uniqueId = 0) {
        frc_frameID_t frame;
        frame.raw = arbid;
        this->name = name;
        this->uniqueId = uniqueId;
        this->deviceTypeId = frame.fields.deviceType;
        this->manufacturerId = frame.fields.manufacturer;
        this->canId = frame.fields.deviceNumber;
    }
 
    std::string Name() const {
        if (name.empty()) {
            return std::string(GetFRCManufacturerText(manufacturerId)) + " " +
                   std::string(GetFRCDeviceTypeText(deviceTypeId));
        } else {
            return name;
        }
    }
};
 
inline bool operator<(const CANScanIdentifier& lhs,
                      const CANScanIdentifier& rhs) {
    return std::tie(lhs.deviceTypeId, lhs.manufacturerId, lhs.canId,
                    lhs.uniqueId) < std::tie(rhs.deviceTypeId,
                                             rhs.manufacturerId, rhs.canId,
                                             rhs.uniqueId);
}
 
inline bool operator>(const CANScanIdentifier& lhs,
                      const CANScanIdentifier& rhs) {
    return std::tie(lhs.deviceTypeId, lhs.manufacturerId, lhs.canId,
                    lhs.uniqueId) > std::tie(rhs.deviceTypeId,
                                             rhs.manufacturerId, rhs.canId,
                                             rhs.uniqueId);
}
 
inline bool operator==(const CANScanIdentifier& lhs,
                       const CANScanIdentifier& rhs) {
    return std::tie(lhs.deviceTypeId, lhs.manufacturerId, lhs.canId,
                    lhs.uniqueId) == std::tie(rhs.deviceTypeId,
                                              rhs.manufacturerId, rhs.canId,
                                              rhs.uniqueId);
}
 
class CANBusScanner {
public:
    // Make sure the buffer size is large enough to capture all needed messages
    // in the thread interval time
    explicit CANBusScanner(int buffersize = 256, int threadIntervalMs = 10);
    ~CANBusScanner();
 
    bool Start();
    void Stop();
    bool Running();
    std::string LastError();
    std::vector<CANScanIdentifier> CANBusScan();
    void RegisterDevice(std::string name, std::vector<uint32_t> validIds,
                        int32_t maxFramePeriodMs = 100);
 
private:
    class CANScanElement {
        uint64_t lastSeen;
        uint64_t timeout;
 
    public:
        explicit CANScanElement(uint64_t timeoutMs = 1000);
        void UpdateLastSeen();
        bool IsActive() const;
    };
 
    class CANScanCollection {
    public:
        CANScanCollection(std::string name, uint32_t arbId, uint64_t timeoutMs)
            : name(name), timeout(timeoutMs), arbId(arbId) {}
 
        std::vector<int> ActiveDevices() const {
            std::vector<int> result;
            for (const auto& [devKey, devValue] : devices) {
                if (devValue.IsActive()) {
                    result.push_back(devKey);
                }
            }
            return result;
        }
 
        void AddOrUpdateDevice(int id) {
            if (devices.find(id) != devices.end()) {
                devices[id] = CANScanElement(timeout);
            }
            devices[id].UpdateLastSeen();
        }
 
        std::string Name() const { return name; }
        uint32_t ArbId() const { return arbId; }
 
    private:
        std::string name;
        uint64_t timeout;
        uint32_t arbId;
        std::unordered_map<int, CANScanElement> devices;
    };
 
    // Data structure is a map of all arbIds that point to a single shared
    // collection and a vector of all collections (same pointer). This allows a
    // fast lookup per arbID received and a way to iterate through by registered
    // device
    std::unordered_map<uint32_t, std::shared_ptr<CANScanCollection> >
        m_registeredDevices;
    std::vector<std::shared_ptr<CANScanCollection> > m_registeredList;
 
    int m_streamBufferSize;
    uint32_t m_streamHandle;
    int m_threadInterval;
 
    std::thread m_thread;
    std::atomic_bool m_stopThread;
    std::atomic_bool m_running;
    std::string m_lastError;
 
    void run();
};
 
}  // namespace detail
}  // namespace rev