pnpimpl.cpp

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/* SPDX-License-Identifier: MIT */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <math.h>
#include <libudev.h>

#include "ajabase/pnp/linux/pnpimpl.h"

static pthread_t child_id = 0;
static bool run = false;

AJAPnpImpl::AJAPnpImpl() : mRefCon(NULL), mCallback(NULL), mDevices(0)
{
}


AJAPnpImpl::~AJAPnpImpl()
{
    Uninstall();
}


AJAStatus 
AJAPnpImpl::Install(AJAPnpCallback callback, void* refCon, uint32_t devices)
{
    mCallback = callback;
    mRefCon   = refCon;
    mDevices  = devices;

    if (!mCallback)
        return AJA_STATUS_NULL; //  NULL callback

    if (child_id)
        Uninstall();

    //  Linux only handles PCIe devices
    if (mDevices & AJA_Pnp_PciVideoDevices)
    {
        run = true;
        pthread_t child;
        if (pthread_create(&child, NULL, *Worker, (void *)this) < 0)
            return AJA_STATUS_FAIL; //  Failed to create Worker thread

        (*(mCallback))(AJA_Pnp_DeviceAdded, mRefCon);

        child_id = child;
        return AJA_STATUS_SUCCESS;
    }
    return AJA_STATUS_FAIL;
}
    

AJAStatus 
AJAPnpImpl::Uninstall(void)
{
    if (child_id == 0)
        return AJA_STATUS_SUCCESS;

    run = false;

    struct timespec tt;
    clock_gettime(CLOCK_REALTIME, &tt);
    tt.tv_sec += 1;;

    pthread_timedjoin_np(child_id, NULL, &tt);

    child_id = 0;
    mCallback = NULL;
    mRefCon = NULL;
    mDevices = 0;

    return AJA_STATUS_SUCCESS;
}


void*
AJAPnpImpl::Worker(void* refCon)
{
    AJAPnpImpl* pPnP = (AJAPnpImpl*)refCon;
    struct udev *udev;
    struct udev_device *dev;
    struct udev_monitor *mon;
    int fd;

    udev = udev_new();
    if (udev == NULL)
    {
        return NULL;
    }

    mon = udev_monitor_new_from_netlink(udev, "udev");
    udev_monitor_filter_add_match_subsystem_devtype(mon, "ajantv2", NULL);
    udev_monitor_enable_receiving(mon);
    fd = udev_monitor_get_fd(mon);

    while (run)
    {
        fd_set fds;
        struct timeval tv;
        int ret;

        FD_ZERO(&fds);
        FD_SET(fd, &fds);
        tv.tv_sec = 0;
        tv.tv_usec = 1000000;

        ret = select(fd+1, &fds, NULL, NULL, &tv);
        if (ret > 0 && FD_ISSET(fd, &fds)) {
            dev = udev_monitor_receive_device(mon);
            if (dev) {
//              printf("I: ACTION=%s\n", udev_device_get_action(dev));
//              printf("I: DEVNAME=%s\n", udev_device_get_sysname(dev));
//              printf("I: DEVPATH=%s\n", udev_device_get_devpath(dev));
                AJAPnpMessage action = AJA_Pnp_DeviceOffline;
                if (strstr(udev_device_get_action(dev), "add") != NULL)
                {
                    action = AJA_Pnp_DeviceAdded;
//                    printf("hotplug add %d\n", count++);
                }
                if (strstr(udev_device_get_action(dev), "remove") != NULL)
                {
                    action = AJA_Pnp_DeviceRemoved;
//                    printf("hotplug remove %d\n", count++);
                }
                if ((action != AJA_Pnp_DeviceOffline) && (pPnP->mCallback != NULL))
                    (*(pPnP->mCallback))(action, pPnP->mRefCon);
                
                udev_device_unref(dev);
            }
        }
    }

    udev_unref(udev);

    return NULL;
}