linux - 找不到 libudev 开发包

Question

我正在编写一个自动检测设备插入/拔出的应用程序。

我将 C++ 与 Qt 框架结合使用。 libudev.h 包含在我的代码中。我实际上通过 sudo apt-get install libudev-dev 安装了 libudev-dev 包，但 QtCreator 仍然有错误消息:libudev 开发包未找到

文件.pro:

...
CONFIG   += console c++11
CONFIG   -= app_bundle
unix: CONFIG += link_pkgconfig
unix: PKGCONFIG += libudev
HEADERS += DeviceManager.h
SOURCES += main.cpp \
  DeviceManager.cpp
...

DeviceManager.h 文件:

#ifndef DEVICEMANAGER_H
#define DEVICEMANAGER_H

#include <QObject>
#include <QDebug>
#include <QSet>
#include <libudev.h>

#include "DeviceModel.h"

class DeviceManager : public QObject
{
    Q_OBJECT
public:
    explicit DeviceManager(QObject *parent = 0);

    QSet<DeviceModel *> getDevices();
    QStringList getDevicePaths();

private:
    QSet<DeviceModel *> pluggedDevices;

};
#endif // DEVICEMANAGER_H

DeviceManager.cpp 文件:

#include "DeviceManager.h"

DeviceManager::DeviceManager(QObject *parent) :
    QObject(parent)
{
}

QSet<DeviceModel *> DeviceManager::getDevices()
{
    QSet<DeviceModel *> devices = QSet<DeviceModel *>();
    struct udev *udev;
    struct udev_enumerate *enumerate;
    struct udev_list_entry *dev_list, *dev_list_entry;
    struct udev_device *dev;
    struct udev_monitor *mon;

    /* Create the udev object */
    udev = udev_new();
    if (!udev)
    {
        qDebug() << "Can't create udev";
        return devices;
    }

    /* Set up a monitor to monitor hidraw devices */
    mon = udev_monitor_new_from_netlink(udev, "udev");
    udev_monitor_filter_add_match_subsystem_devtype(mon, "usb", "usb_device");
    udev_monitor_enable_receiving(mon);

    enumerate = udev_enumerate_new(udev);
    udev_enumerate_add_match_subsystem(enumerate, "usb");
    udev_enumerate_scan_devices(enumerate);
    dev_list = udev_enumerate_get_list_entry(enumerate);
    QString vendorID, serialNumber, devName, deviceName;
    udev_list_entry_foreach(dev_list_entry, dev_list)
    {
        const char *path;
        path = udev_list_entry_get_name(dev_list_entry);
        dev = udev_device_new_from_syspath(udev, path);

        udev_device_get_parent_with_subsystem_devtype(dev, "usb", "usb_device");

        if (!dev)
        {
            qDebug() << "Unable to find parent usb device.";
            return devices;
        }
        vendorID = udev_device_get_property_value(dev, "ID_VENDOR_ID");
        devName = udev_device_get_property_value(dev, "DEVNAME");
        if (!vendorID.isNull() && vendorID.compare("04e8") == 0)    // vendor ID of Samsung devices
        {
                DeviceModel *device = new DeviceModel();
                serialNumber = udev_device_get_property_value(dev, "ID_SERIAL_SHORT");
                deviceName = QString(udev_device_get_property_value(dev, "DEVPATH")).split("/").last();
                if (!serialNumber.isNull())
                {
                    device->setDownloadMode(false);
                    device->setSerialNumber(serialNumber);
                }
                else if(!devName.isNull())
                {
                    device->setPath(devName);
                    device->setDownloadMode(true);
                }
                else
                    break;
                device->setName(deviceName);
                devices.insert(device);
        }
        udev_device_unref(dev);
    }
    /* Free the enumerator object */
    udev_enumerate_unref(enumerate);
    udev_unref(udev);
    this->pluggedDevices = devices;
    return devices;
}

QStringList DeviceManager::getDevicePaths()
{
    QStringList result;
    if (this->pluggedDevices.isEmpty())
    {
        return result;
    }
    foreach (DeviceModel *device, this->pluggedDevices)
    {
        result.append(device->getPath());
    }
    return result;
}

环境:

操作系统:Ubuntu 18.04.2 LTS

Qt Creator 4.5.2 基于 Qt 5.9.5 (GCC 7.3.0, 64bit)

你能帮我找个理由吗？

Answer 1

错误消息表明您缺少 libudev-dev 或 pkg-config。由于您已经安装了 libudev-dev，这意味着您缺少的是 pkg-config 工具。如果命令:

pkg-config --version

不打印像这样的东西:

0.29.1

那么您缺少 pkg-config 工具。安装它:

sudo apt install pkg-config

这应该可以解决您的问题。请记住从您的项目文件中删除 LIBS += -ludev。您只需要 PKGCONFIG += libudev。