diff --git a/qt/logger.cpp b/qt/logger.cpp
new file mode 100644
index 0000000..d8a3e57
--- /dev/null
+++ b/qt/logger.cpp
@@ -0,0 +1,45 @@
+#include "logger.h"
+
+#include <QDebug>
+
+Logger::Logger(QObject *parent)
+ : QObject(parent),
+ socket(Q_NULLPTR)
+{
+
+}
+
+bool Logger::init(const QString &tag)
+{
+ this->tag = tag;
+ if (socket == Q_NULLPTR)
+ socket = new UnixDomainDatagramSocket(this);
+
+ return socket->open();
+}
+
+void Logger::print(const QString &string)
+{
+ QByteArray bytes(string.toLocal8Bit().data());
+ bytes.prepend(' ').prepend(tag.toLocal8Bit().data());
+
+ qDebug() << bytes;
+
+ socket->writeDatagram(bytes, "/tmp/logger.uds");
+}
+
+void Logger::hexdump(const QString &message, const QByteArray &bytes)
+{
+ QByteArray line;
+ line += tag + " " + message + " [";
+ for (int i = 0; i < bytes.length(); i++)
+ {
+ line += QByteArray::number(uchar(bytes.at(i)), 16).toUpper();
+ line += " ";
+ }
+ line = line.trimmed();
+ line += "]\n";
+
+ qDebug() << line;
+ socket->writeDatagram(line, "/tmp/logger.uds");
+}
diff --git a/qt/logger.h b/qt/logger.h
new file mode 100644
index 0000000..d8920db
--- /dev/null
+++ b/qt/logger.h
@@ -0,0 +1,29 @@
+// Logger는 pool sw의 app-logger를 사용할 수 있게 해준다.
+
+#ifndef LOGGER_H
+#define LOGGER_H
+
+#include <QObject>
+
+#include "unixdomaindatagramsocket.h"
+
+class Logger : public QObject
+{
+ Q_OBJECT
+public:
+ explicit Logger(QObject *parent = nullptr);
+
+ bool init(const QString &tag);
+
+signals:
+
+public slots:
+ void print(const QString &string);
+ void hexdump(const QString &message, const QByteArray &bytes);
+
+private:
+ UnixDomainDatagramSocket *socket;
+ QString tag;
+};
+
+#endif // LOGGER_H
diff --git a/qt/unixdomaindatagramsocket.cpp b/qt/unixdomaindatagramsocket.cpp
new file mode 100644
index 0000000..159f621
--- /dev/null
+++ b/qt/unixdomaindatagramsocket.cpp
@@ -0,0 +1,152 @@
+#include "unixdomaindatagramsocket.h"
+
+#include <QVarLengthArray>
+
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/ioctl.h>
+#include <linux/sockios.h>
+
+UnixDomainDatagramSocket::UnixDomainDatagramSocket(QObject *parent)
+ : QObject(parent),
+ sockfd(-1), notifier(Q_NULLPTR)
+{
+
+}
+
+UnixDomainDatagramSocket::~UnixDomainDatagramSocket()
+{
+ if (sockfd >= 0)
+ close(sockfd);
+
+ if (!boundPath.isEmpty())
+ unlink(boundPath.toLocal8Bit().data());
+}
+
+bool UnixDomainDatagramSocket::open()
+{
+ if (sockfd >= 0)
+ return false;
+
+ sockfd = socket(AF_UNIX, SOCK_DGRAM, 0);
+ if (sockfd < 0)
+ return false;
+
+ notifier = new QSocketNotifier(sockfd, QSocketNotifier::Read, this);
+ connect(notifier, SIGNAL(activated(int)), SLOT(emitReadyRead()));
+
+ return true;
+}
+
+bool UnixDomainDatagramSocket::bind(const QString &path)
+{
+ return bind(path.toLocal8Bit().data());
+}
+
+bool UnixDomainDatagramSocket::bind(const char *path)
+{
+ if (sockfd < 0 && !open())
+ return false;
+
+ unlink(path);
+
+ struct sockaddr_un address;
+ address.sun_family = AF_UNIX;
+ strncpy(address.sun_path, path, sizeof(address.sun_path));
+
+ int ret = ::bind(sockfd, reinterpret_cast<struct sockaddr *>(&address), sizeof(address));
+ if (ret == -1)
+ return false;
+
+ return true;
+}
+
+bool UnixDomainDatagramSocket::hasPendingDatagrams()
+{
+ ssize_t readBytes;
+ do
+ {
+ char c;
+ readBytes = ::recv(sockfd, &c, 1, MSG_DONTWAIT | MSG_PEEK);
+ }
+ while (readBytes == -1 && errno == EINTR);
+
+ return (readBytes != -1) || errno == EMSGSIZE;
+}
+
+qint64 UnixDomainDatagramSocket::pendingDatagramSize()
+{
+ QVarLengthArray<char, 8192> udpMessagePeekBuffer(8192);
+ ssize_t recvResult = -1;
+
+ for (;;)
+ {
+ recvResult = ::recv(sockfd, udpMessagePeekBuffer.data(),
+ size_t(udpMessagePeekBuffer.size()), MSG_DONTWAIT | MSG_PEEK);
+ if (recvResult == -1 && errno == EINTR)
+ continue;
+
+ if (recvResult != ssize_t(udpMessagePeekBuffer.size()))
+ break;
+
+ udpMessagePeekBuffer.resize(udpMessagePeekBuffer.size() * 2);
+ }
+
+ return qint64(recvResult);
+}
+
+qint64 UnixDomainDatagramSocket::readDatagram(QByteArray *datagram, QString *path)
+{
+ return readDatagram(datagram->data(), datagram->size(), path);
+}
+
+qint64 UnixDomainDatagramSocket::readDatagram(char *data, qint64 maxSize, QString *path)
+{
+ if (!notifier->isEnabled())
+ notifier->setEnabled(true);
+
+ struct sockaddr_un address;
+ socklen_t length;
+
+ ssize_t recvResult;
+ do
+ {
+ recvResult = ::recvfrom(sockfd, data, size_t(maxSize), 0, reinterpret_cast<struct sockaddr *>(&address), &length);
+ }
+ while (recvResult == -1 && errno == EINTR);
+
+ if (recvResult == -1)
+ return -1;
+
+ if (path)
+ *path = QString::fromLocal8Bit(address.sun_path);
+
+ return recvResult;
+}
+
+qint64 UnixDomainDatagramSocket::writeDatagram(const QByteArray &datagram, const QString &path)
+{
+ return writeDatagram(datagram.data(), datagram.size(), path);
+}
+
+qint64 UnixDomainDatagramSocket::writeDatagram(const char *data, qint64 size, const QString &path)
+{
+ return writeDatagram(data, size, path.toLocal8Bit().data());
+}
+
+qint64 UnixDomainDatagramSocket::writeDatagram(const char *data, qint64 size, const char *path)
+{
+ struct sockaddr_un address;
+ address.sun_family = AF_UNIX;
+ strncpy(address.sun_path, path, sizeof(address.sun_path));
+
+ ssize_t sendResult = ::sendto(sockfd, data, size_t(size), 0, reinterpret_cast<struct sockaddr *>(&address), sizeof(address));
+ return qint64(sendResult);
+}
+
+void UnixDomainDatagramSocket::emitReadyRead()
+{
+ notifier->setEnabled(false);
+ emit readyRead();
+}
diff --git a/qt/unixdomaindatagramsocket.h b/qt/unixdomaindatagramsocket.h
new file mode 100644
index 0000000..419f35d
--- /dev/null
+++ b/qt/unixdomaindatagramsocket.h
@@ -0,0 +1,44 @@
+// UnixDomainDatagramSocket은 UDS를 데이터그램 형식으로 사용하는 소켓 구현체다. QUdpSocket처럼 사용하도록 구현했다.
+//
+// 주의: 자동 변수 대신 new로 할당하라. 소멸자에서 열린 소켓을 닫고 만든 파일을 지우기 때문에 문제가 생길 수 있다.
+
+#ifndef UNIXDOMAINDATAGRAMSOCKET_H
+#define UNIXDOMAINDATAGRAMSOCKET_H
+
+#include <QObject>
+#include <QSocketNotifier>
+
+class UnixDomainDatagramSocket : public QObject
+{
+ Q_OBJECT
+public:
+ explicit UnixDomainDatagramSocket(QObject *parent = Q_NULLPTR);
+ ~UnixDomainDatagramSocket();
+
+ bool open();
+ bool bind(const QString &path);
+ bool bind(const char *path);
+
+ bool hasPendingDatagrams();
+ qint64 pendingDatagramSize();
+ qint64 readDatagram(QByteArray *datagram, QString *path = Q_NULLPTR);
+ qint64 readDatagram(char *data, qint64 maxSize, QString *path = Q_NULLPTR);
+ qint64 writeDatagram(const QByteArray &datagram, const QString &path);
+ qint64 writeDatagram(const char *data, qint64 size, const QString &path);
+ qint64 writeDatagram(const char *data, qint64 size, const char *path);
+
+signals:
+ void readyRead();
+
+public slots:
+
+private:
+ int sockfd;
+ QString boundPath;
+ QSocketNotifier *notifier;
+
+private slots:
+ void emitReadyRead();
+};
+
+#endif // UNIXDOMAINDATAGRAMSOCKET_H