20 files changed, 1878 insertions, 0 deletions

diff --git a/src/system/EPollFD.cxx b/src/system/EPollFD.cxx
new file mode 100644
index 000000000..5721c0194
--- /dev/null
+++ b/src/system/EPollFD.cxx
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#ifdef USE_EPOLL
+#include "EPollFD.hxx"
+#include "FatalError.hxx"
+
+EPollFD::EPollFD()
+	:fd(::epoll_create1(EPOLL_CLOEXEC))
+{
+	if (fd < 0)
+		FatalSystemError("epoll_create1() failed");
+}
+
+#endif /* USE_EPOLL */
diff --git a/src/system/EPollFD.hxx b/src/system/EPollFD.hxx
new file mode 100644
index 000000000..41f7ec377
--- /dev/null
+++ b/src/system/EPollFD.hxx
@@ -0,0 +1,80 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_EPOLL_FD_HXX
+#define MPD_EPOLL_FD_HXX
+
+#include <assert.h>
+#include <sys/epoll.h>
+#include <unistd.h>
+
+#include "check.h"
+
+struct epoll_event;
+
+/**
+ * A class that wraps Linux epoll.
+ *
+ * Errors in the constructor are fatal.
+ */
+class EPollFD {
+	const int fd;
+
+public:
+	EPollFD();
+
+	~EPollFD() {
+		assert(fd >= 0);
+
+		::close(fd);
+	}
+
+	EPollFD(const EPollFD &other) = delete;
+	EPollFD &operator=(const EPollFD &other) = delete;
+
+	int Wait(epoll_event *events, int maxevents, int timeout) {
+		return ::epoll_wait(fd, events, maxevents, timeout);
+	}
+
+	bool Control(int op, int _fd, epoll_event *event) {
+		return ::epoll_ctl(fd, op, _fd, event) >= 0;
+	}
+
+	bool Add(int _fd, uint32_t events, void *ptr) {
+		epoll_event e;
+		e.events = events;
+		e.data.ptr = ptr;
+
+		return Control(EPOLL_CTL_ADD, _fd, &e);
+	}
+
+	bool Modify(int _fd, uint32_t events, void *ptr) {
+		epoll_event e;
+		e.events = events;
+		e.data.ptr = ptr;
+
+		return Control(EPOLL_CTL_MOD, _fd, &e);
+	}
+
+	bool Remove(int _fd) {
+		return Control(EPOLL_CTL_DEL, _fd, nullptr);
+	}
+};
+
+#endif
diff --git a/src/system/EventFD.cxx b/src/system/EventFD.cxx
new file mode 100644
index 000000000..716ff80ae
--- /dev/null
+++ b/src/system/EventFD.cxx
@@ -0,0 +1,65 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#ifdef USE_EVENTFD
+#include "EventFD.hxx"
+#include "system/fd_util.h"
+#include "system/FatalError.hxx"
+#include "gcc.h"
+
+#include <assert.h>
+#include <unistd.h>
+
+#include <sys/eventfd.h>
+
+EventFD::EventFD()
+	:fd(eventfd_cloexec_nonblock(0, 0))
+{
+	if (fd < 0)
+		FatalSystemError("eventfd() failed");
+}
+
+EventFD::~EventFD()
+{
+	assert(fd >= 0);
+
+	close(fd);
+}
+
+bool
+EventFD::Read()
+{
+	assert(fd >= 0);
+
+	eventfd_t value;
+	return read(fd, &value, sizeof(value)) == (ssize_t)sizeof(value);
+}
+
+void
+EventFD::Write()
+{
+	assert(fd >= 0);
+
+	static constexpr eventfd_t value = 1;
+	gcc_unused ssize_t nbytes =
+		write(fd, &value, sizeof(value));
+}
+
+#endif /* USE_EVENTFD */
diff --git a/src/system/EventFD.hxx b/src/system/EventFD.hxx
new file mode 100644
index 000000000..67a0258ab
--- /dev/null
+++ b/src/system/EventFD.hxx
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_EVENT_FD_HXX
+#define MPD_EVENT_FD_HXX
+
+#include "check.h"
+
+/**
+ * A class that wraps eventfd().
+ *
+ * Errors in the constructor are fatal.
+ */
+class EventFD {
+	int fd;
+
+public:
+	EventFD();
+	~EventFD();
+
+	EventFD(const EventFD &other) = delete;
+	EventFD &operator=(const EventFD &other) = delete;
+
+	int Get() const {
+		return fd;
+	}
+
+	/**
+	 * Checks if Write() was called at least once since the last
+	 * Read() call.
+	 */
+	bool Read();
+
+	/**
+	 * Wakes up the reader.  Multiple calls to this function will
+	 * be combined to one wakeup.
+	 */
+	void Write();
+};
+
+#endif
diff --git a/src/system/EventPipe.cxx b/src/system/EventPipe.cxx
new file mode 100644
index 000000000..e1a38c503
--- /dev/null
+++ b/src/system/EventPipe.cxx
@@ -0,0 +1,180 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "EventPipe.hxx"
+#include "system/fd_util.h"
+#include "system/FatalError.hxx"
+#include "gcc.h"
+
+#include <assert.h>
+#include <unistd.h>
+
+#ifdef WIN32
+#include <ws2tcpip.h>
+#include <winsock2.h>
+#include <cstring> /* for memset() */
+#endif
+
+#ifdef WIN32
+static bool PoorSocketPair(int fd[2]);
+#endif
+
+EventPipe::EventPipe()
+{
+#ifdef WIN32
+	bool success = PoorSocketPair(fds);
+#else
+	bool success = pipe_cloexec_nonblock(fds) >= 0;
+#endif
+	if (!success)
+		FatalSystemError("pipe() has failed");
+}
+
+EventPipe::~EventPipe()
+{
+#ifdef WIN32
+	closesocket(fds[0]);
+	closesocket(fds[1]);
+#else
+	close(fds[0]);
+	close(fds[1]);
+#endif
+}
+
+bool
+EventPipe::Read()
+{
+	assert(fds[0] >= 0);
+	assert(fds[1] >= 0);
+
+	char buffer[256];
+#ifdef WIN32
+	return recv(fds[0], buffer, sizeof(buffer), 0) > 0;
+#else
+	return read(fds[0], buffer, sizeof(buffer)) > 0;
+#endif
+}
+
+void
+EventPipe::Write()
+{
+	assert(fds[0] >= 0);
+	assert(fds[1] >= 0);
+
+#ifdef WIN32
+	send(fds[1], "", 1, 0);
+#else
+	gcc_unused ssize_t nbytes = write(fds[1], "", 1);
+#endif
+}
+
+#ifdef WIN32
+
+static void SafeCloseSocket(SOCKET s)
+{
+	int error = WSAGetLastError();
+	closesocket(s);
+	WSASetLastError(error);
+}
+
+/* Our poor man's socketpair() implementation
+ * Due to limited protocol/address family support and primitive error handling
+ * it's better to keep this as a private implementation detail of EventPipe
+ * rather than wide-available API.
+ */
+static bool PoorSocketPair(int fd[2])
+{
+	assert (fd != nullptr);
+
+	SOCKET listen_socket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+	if (listen_socket == INVALID_SOCKET)
+		return false;
+
+	sockaddr_in address;
+	std::memset(&address, 0, sizeof(address));
+	address.sin_family = AF_INET;
+	address.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+
+	int ret = bind(listen_socket,
+		       reinterpret_cast<sockaddr*>(&address),
+		       sizeof(address));
+
+	if (ret < 0) {
+		SafeCloseSocket(listen_socket);
+		return false;
+	}
+
+	ret = listen(listen_socket, 1);
+
+	if (ret < 0) {
+		SafeCloseSocket(listen_socket);
+		return false;
+	}
+
+	int address_len = sizeof(address);
+	ret = getsockname(listen_socket,
+			  reinterpret_cast<sockaddr*>(&address),
+			  &address_len);
+
+	if (ret < 0) {
+		SafeCloseSocket(listen_socket);
+		return false;
+	}
+
+	SOCKET socket0 = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
+	if (socket0 == INVALID_SOCKET) {
+		SafeCloseSocket(listen_socket);
+		return false;
+	}
+
+	ret = connect(socket0,
+		      reinterpret_cast<sockaddr*>(&address),
+		      sizeof(address));
+
+	if (ret < 0) {
+		SafeCloseSocket(listen_socket);
+		SafeCloseSocket(socket0);
+		return false;
+	}
+
+	SOCKET socket1 = accept(listen_socket, nullptr, nullptr);
+	if (socket1 == INVALID_SOCKET) {
+		SafeCloseSocket(listen_socket);
+		SafeCloseSocket(socket0);
+		return false;
+	}
+
+	SafeCloseSocket(listen_socket);
+
+	u_long non_block = 1;
+	if (ioctlsocket(socket0, FIONBIO, &non_block) < 0
+	    || ioctlsocket(socket1, FIONBIO, &non_block) < 0) {
+		SafeCloseSocket(socket0);
+		SafeCloseSocket(socket1);
+		return false;
+	}
+
+	fd[0] = static_cast<int>(socket0);
+	fd[1] = static_cast<int>(socket1);
+
+	return true;
+}
+
+#endif
diff --git a/src/system/EventPipe.hxx b/src/system/EventPipe.hxx
new file mode 100644
index 000000000..86a10b0bb
--- /dev/null
+++ b/src/system/EventPipe.hxx
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_EVENT_PIPE_HXX
+#define MPD_EVENT_PIPE_HXX
+
+#include "check.h"
+
+/**
+ * A pipe that can be used to trigger an event to the read side.
+ *
+ * Errors in the constructor are fatal.
+ */
+class EventPipe {
+	int fds[2];
+
+public:
+	EventPipe();
+	~EventPipe();
+
+	EventPipe(const EventPipe &other) = delete;
+	EventPipe &operator=(const EventPipe &other) = delete;
+
+	int Get() const {
+		return fds[0];
+	}
+
+	/**
+	 * Checks if Write() was called at least once since the last
+	 * Read() call.
+	 */
+	bool Read();
+
+	/**
+	 * Wakes up the reader.  Multiple calls to this function will
+	 * be combined to one wakeup.
+	 */
+	void Write();
+};
+
+#endif /* MAIN_NOTIFY_H */
diff --git a/src/system/FatalError.cxx b/src/system/FatalError.cxx
new file mode 100644
index 000000000..7c0dc942a
--- /dev/null
+++ b/src/system/FatalError.cxx
@@ -0,0 +1,105 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "FatalError.hxx"
+#include "util/Error.hxx"
+
+#include <glib.h>
+
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stdio.h>
+
+#ifdef WIN32
+#include <windows.h>
+#else
+#include <errno.h>
+#endif
+
+#undef G_LOG_DOMAIN
+#define G_LOG_DOMAIN "FatalError"
+
+void
+FatalError(const char *msg)
+{
+	g_critical("%s", msg);
+	exit(EXIT_FAILURE);
+}
+
+void
+FormatFatalError(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	g_logv(G_LOG_DOMAIN, G_LOG_LEVEL_CRITICAL, fmt, ap);
+	va_end(ap);
+
+	exit(EXIT_FAILURE);
+}
+
+void
+FatalError(const Error &error)
+{
+	FatalError(error.GetMessage());
+}
+
+void
+FatalError(const char *msg, const Error &error)
+{
+	FormatFatalError("%s: %s", msg, error.GetMessage());
+}
+
+void
+FatalError(GError *error)
+{
+	FatalError(error->message);
+}
+
+void
+FatalError(const char *msg, GError *error)
+{
+	FormatFatalError("%s: %s", msg, error->message);
+}
+
+void
+FatalSystemError(const char *msg)
+{
+	const char *system_error;
+#ifdef WIN32
+	system_error = g_win32_error_message(GetLastError());
+#else
+	system_error = g_strerror(errno);
+#endif
+
+	g_critical("%s: %s", msg, system_error);
+	exit(EXIT_FAILURE);
+}
+
+void
+FormatFatalSystemError(const char *fmt, ...)
+{
+	char buffer[1024];
+	va_list ap;
+	va_start(ap, fmt);
+	vsnprintf(buffer, sizeof(buffer), fmt, ap);
+	va_end(ap);
+
+	FatalSystemError(buffer);
+}
diff --git a/src/system/FatalError.hxx b/src/system/FatalError.hxx
new file mode 100644
index 000000000..03baf66c4
--- /dev/null
+++ b/src/system/FatalError.hxx
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_FATAL_ERROR_HXX
+#define MPD_FATAL_ERROR_HXX
+
+#include "check.h"
+#include "gerror.h"
+#include "gcc.h"
+
+class Error;
+
+/**
+ * Log the specified message and abort the process.
+ */
+gcc_noreturn
+void
+FatalError(const char *msg);
+
+gcc_noreturn
+void
+FormatFatalError(const char *fmt, ...);
+
+gcc_noreturn
+void
+FatalError(const Error &error);
+
+gcc_noreturn
+void
+FatalError(const char *msg, const Error &error);
+
+gcc_noreturn
+void
+FatalError(GError *error);
+
+gcc_noreturn
+void
+FatalError(const char *msg, GError *error);
+
+/**
+ * Call this after a system call has failed that is not supposed to
+ * fail.  Prints the given message, the system error message (from
+ * errno or GetLastError()) and abort the process.
+ */
+gcc_noreturn
+void
+FatalSystemError(const char *msg);
+
+gcc_noreturn
+void
+FormatFatalSystemError(const char *fmt, ...);
+
+#endif
diff --git a/src/system/Resolver.cxx b/src/system/Resolver.cxx
new file mode 100644
index 000000000..51a5b1ed7
--- /dev/null
+++ b/src/system/Resolver.cxx
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "Resolver.hxx"
+#include "util/Error.hxx"
+#include "util/Domain.hxx"
+
+#include <glib.h>
+
+#ifndef G_OS_WIN32
+#include <sys/socket.h>
+#include <netdb.h>
+#else /* G_OS_WIN32 */
+#include <ws2tcpip.h>
+#include <winsock.h>
+#endif /* G_OS_WIN32 */
+
+#include <string.h>
+#include <stdio.h>
+
+const Domain resolver_domain("resolver");
+
+char *
+sockaddr_to_string(const struct sockaddr *sa, size_t length, Error &error)
+{
+#if defined(HAVE_IPV6) && defined(IN6_IS_ADDR_V4MAPPED)
+	const struct sockaddr_in6 *a6 = (const struct sockaddr_in6 *)sa;
+	struct sockaddr_in a4;
+#endif
+	int ret;
+	char host[NI_MAXHOST], serv[NI_MAXSERV];
+
+#if defined(HAVE_IPV6) && defined(IN6_IS_ADDR_V4MAPPED)
+	if (sa->sa_family == AF_INET6 &&
+	    IN6_IS_ADDR_V4MAPPED(&a6->sin6_addr)) {
+		/* convert "::ffff:127.0.0.1" to "127.0.0.1" */
+
+		memset(&a4, 0, sizeof(a4));
+		a4.sin_family = AF_INET;
+		memcpy(&a4.sin_addr, ((const char *)&a6->sin6_addr) + 12,
+		       sizeof(a4.sin_addr));
+		a4.sin_port = a6->sin6_port;
+
+		sa = (const struct sockaddr *)&a4;
+		length = sizeof(a4);
+	}
+#endif
+
+	ret = getnameinfo(sa, length, host, sizeof(host), serv, sizeof(serv),
+			  NI_NUMERICHOST|NI_NUMERICSERV);
+	if (ret != 0) {
+		error.Set(resolver_domain, ret, gai_strerror(ret));
+		return NULL;
+	}
+
+#ifdef HAVE_UN
+	if (sa->sa_family == AF_UNIX)
+		/* "serv" contains corrupt information with unix
+		   sockets */
+		return g_strdup(host);
+#endif
+
+#ifdef HAVE_IPV6
+	if (strchr(host, ':') != NULL)
+		return g_strconcat("[", host, "]:", serv, NULL);
+#endif
+
+	return g_strconcat(host, ":", serv, NULL);
+}
+
+struct addrinfo *
+resolve_host_port(const char *host_port, unsigned default_port,
+		  int flags, int socktype,
+		  Error &error)
+{
+	char *p = g_strdup(host_port);
+	const char *host = p, *port = NULL;
+
+	if (host_port[0] == '[') {
+		/* IPv6 needs enclosing square braces, to
+		   differentiate between IP colons and the port
+		   separator */
+
+		char *q = strchr(p + 1, ']');
+		if (q != NULL && q[1] == ':' && q[2] != 0) {
+			*q = 0;
+			++host;
+			port = q + 2;
+		}
+	}
+
+	if (port == NULL) {
+		/* port is after the colon, but only if it's the only
+		   colon (don't split IPv6 addresses) */
+
+		char *q = strchr(p, ':');
+		if (q != NULL && q[1] != 0 && strchr(q + 1, ':') == NULL) {
+			*q = 0;
+			port = q + 1;
+		}
+	}
+
+	char buffer[32];
+	if (port == NULL && default_port != 0) {
+		snprintf(buffer, sizeof(buffer), "%u", default_port);
+		port = buffer;
+	}
+
+	if ((flags & AI_PASSIVE) != 0 && strcmp(host, "*") == 0)
+		host = NULL;
+
+	addrinfo hints;
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_flags = flags;
+	hints.ai_family = AF_UNSPEC;
+	hints.ai_socktype = socktype;
+
+	struct addrinfo *ai;
+	int ret = getaddrinfo(host, port, &hints, &ai);
+	g_free(p);
+	if (ret != 0) {
+		error.Format(resolver_domain, ret,
+			     "Failed to look up '%s': %s",
+			     host_port, gai_strerror(ret));
+		return NULL;
+	}
+
+	return ai;
+}
diff --git a/src/system/Resolver.hxx b/src/system/Resolver.hxx
new file mode 100644
index 000000000..38803dcd1
--- /dev/null
+++ b/src/system/Resolver.hxx
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_RESOLVER_HXX
+#define MPD_RESOLVER_HXX
+
+#include "gcc.h"
+
+#include <stddef.h>
+
+struct sockaddr;
+struct addrinfo;
+class Error;
+
+extern const class Domain resolver_domain;
+
+/**
+ * Converts the specified socket address into a string in the form
+ * "IP:PORT".  The return value must be freed with g_free() when you
+ * don't need it anymore.
+ *
+ * @param sa the sockaddr struct
+ * @param length the length of #sa in bytes
+ * @param error location to store the error occurring, or NULL to
+ * ignore errors
+ */
+gcc_malloc
+char *
+sockaddr_to_string(const struct sockaddr *sa, size_t length, Error &error);
+
+/**
+ * Resolve a specification in the form "host", "host:port",
+ * "[host]:port".  This is a convenience wrapper for getaddrinfo().
+ *
+ * @param default_port a default port number that will be used if none
+ * is given in the string (if applicable); pass 0 to go without a
+ * default
+ * @return an #addrinfo linked list that must be freed with
+ * freeaddrinfo(), or NULL on error
+ */
+struct addrinfo *
+resolve_host_port(const char *host_port, unsigned default_port,
+		  int flags, int socktype,
+		  Error &error);
+
+#endif
diff --git a/src/system/SignalFD.cxx b/src/system/SignalFD.cxx
new file mode 100644
index 000000000..b89775dcd
--- /dev/null
+++ b/src/system/SignalFD.cxx
@@ -0,0 +1,58 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#ifdef USE_SIGNALFD
+#include "SignalFD.hxx"
+#include "fd_util.h"
+#include "FatalError.hxx"
+
+#include <assert.h>
+#include <unistd.h>
+#include <sys/signalfd.h>
+
+void
+SignalFD::Create(const sigset_t &mask)
+{
+	fd = ::signalfd(fd, &mask, SFD_NONBLOCK|SFD_CLOEXEC);
+	if (fd < 0)
+		FatalSystemError("signalfd() failed");
+}
+
+void
+SignalFD::Close()
+{
+	if (fd >= 0) {
+		::close(fd);
+		fd = -1;
+	}
+}
+
+int
+SignalFD::Read()
+{
+	assert(fd >= 0);
+
+	signalfd_siginfo info;
+	return read(fd, &info, sizeof(info)) > 0
+		? info.ssi_signo
+		: -1;
+}
+
+#endif /* USE_SIGNALFD */
diff --git a/src/system/SignalFD.hxx b/src/system/SignalFD.hxx
new file mode 100644
index 000000000..7163782d1
--- /dev/null
+++ b/src/system/SignalFD.hxx
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_SIGNAL_FD_HXX
+#define MPD_SIGNAL_FD_HXX
+
+#include "check.h"
+
+#include <signal.h>
+
+/**
+ * A class that wraps signalfd().
+ */
+class SignalFD {
+	int fd;
+
+public:
+	SignalFD():fd(-1) {}
+	~SignalFD() {
+		Close();
+	}
+
+	SignalFD(const SignalFD &other) = delete;
+	SignalFD &operator=(const SignalFD &other) = delete;
+
+	/**
+	 * Create the signalfd or update its mask.
+	 *
+	 * All errors are fatal.
+	 */
+	void Create(const sigset_t &mask);
+	void Close();
+
+	int Get() const {
+		return fd;
+	}
+
+	/**
+	 * Read the next signal from the file descriptor.  Returns the
+	 * signal number on success or -1 if there are no more
+	 * signals.
+	 */
+	int Read();
+};
+
+#endif
diff --git a/src/system/SocketError.cxx b/src/system/SocketError.cxx
new file mode 100644
index 000000000..315a86e1f
--- /dev/null
+++ b/src/system/SocketError.cxx
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "SocketError.hxx"
+#include "util/Domain.hxx"
+
+#include <glib.h>
+
+const Domain socket_domain("socket");
+
+#ifdef WIN32
+
+SocketErrorMessage::SocketErrorMessage(socket_error_t code)
+{
+	DWORD nbytes = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM |
+				     FORMAT_MESSAGE_IGNORE_INSERTS |
+				     FORMAT_MESSAGE_MAX_WIDTH_MASK,
+				     NULL, code, 0,
+				     (LPSTR)msg, sizeof(msg), NULL);
+	if (nbytes == 0)
+		strcpy(msg, "Unknown error");
+}
+
+#else
+
+SocketErrorMessage::SocketErrorMessage(socket_error_t code)
+	:msg(g_strerror(code)) {}
+
+#endif
diff --git a/src/system/SocketError.hxx b/src/system/SocketError.hxx
new file mode 100644
index 000000000..2b8332715
--- /dev/null
+++ b/src/system/SocketError.hxx
@@ -0,0 +1,137 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_SOCKET_ERROR_HXX
+#define MPD_SOCKET_ERROR_HXX
+
+#include "gcc.h"
+#include "util/Error.hxx"
+
+#ifdef WIN32
+#include <winsock2.h>
+typedef DWORD socket_error_t;
+#else
+#include <errno.h>
+typedef int socket_error_t;
+#endif
+
+/**
+ * A #Domain for #Error for socket I/O errors.  The code is an errno
+ * value (or WSAGetLastError() on Windows).
+ */
+extern const class Domain socket_domain;
+
+gcc_pure
+static inline socket_error_t
+GetSocketError()
+{
+#ifdef WIN32
+	return WSAGetLastError();
+#else
+	return errno;
+#endif
+}
+
+gcc_const
+static inline bool
+IsSocketErrorAgain(socket_error_t code)
+{
+#ifdef WIN32
+	return code == WSAEINPROGRESS;
+#else
+	return code == EAGAIN;
+#endif
+}
+
+gcc_const
+static inline bool
+IsSocketErrorInterruped(socket_error_t code)
+{
+#ifdef WIN32
+	return code == WSAEINTR;
+#else
+	return code == EINTR;
+#endif
+}
+
+gcc_const
+static inline bool
+IsSocketErrorClosed(socket_error_t code)
+{
+#ifdef WIN32
+	return code == WSAECONNRESET;
+#else
+	return code == EPIPE || code == ECONNRESET;
+#endif
+}
+
+/**
+ * Helper class that formats a socket error message into a
+ * human-readable string.  On Windows, a buffer is necessary for this,
+ * and this class hosts the buffer.
+ */
+class SocketErrorMessage {
+#ifdef WIN32
+	char msg[256];
+#else
+	const char *const msg;
+#endif
+
+public:
+#ifdef WIN32
+	explicit SocketErrorMessage(socket_error_t code=GetSocketError());
+#else
+	explicit SocketErrorMessage(socket_error_t code=GetSocketError());
+#endif
+
+	operator const char *() const {
+		return msg;
+	}
+};
+
+static inline void
+SetSocketError(Error &error, socket_error_t code)
+{
+	const SocketErrorMessage msg(code);
+	error.Set(socket_domain, code, msg);
+}
+
+static inline void
+SetSocketError(Error &error)
+{
+	SetSocketError(error, GetSocketError());
+}
+
+gcc_const
+static inline Error
+NewSocketError(socket_error_t code)
+{
+	Error error;
+	SetSocketError(error, code);
+	return error;
+}
+
+gcc_pure
+static inline Error
+NewSocketError()
+{
+	return NewSocketError(GetSocketError());
+}
+
+#endif
diff --git a/src/system/SocketUtil.cxx b/src/system/SocketUtil.cxx
new file mode 100644
index 000000000..abaedb8e7
--- /dev/null
+++ b/src/system/SocketUtil.cxx
@@ -0,0 +1,95 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include "config.h"
+#include "SocketUtil.hxx"
+#include "SocketError.hxx"
+#include "fd_util.h"
+
+#include <glib.h>
+
+#include <unistd.h>
+
+#ifndef G_OS_WIN32
+#include <sys/socket.h>
+#else /* G_OS_WIN32 */
+#include <ws2tcpip.h>
+#include <winsock.h>
+#endif /* G_OS_WIN32 */
+
+#ifdef HAVE_IPV6
+#include <string.h>
+#endif
+
+int
+socket_bind_listen(int domain, int type, int protocol,
+		   const struct sockaddr *address, size_t address_length,
+		   int backlog,
+		   Error &error)
+{
+	int fd, ret;
+	const int reuse = 1;
+
+	fd = socket_cloexec_nonblock(domain, type, protocol);
+	if (fd < 0) {
+		SetSocketError(error);
+		error.AddPrefix("Failed to create socket: ");
+		return -1;
+	}
+
+	ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+			 (const char *) &reuse, sizeof(reuse));
+	if (ret < 0) {
+		SetSocketError(error);
+		error.AddPrefix("setsockopt() failed: ");
+		close_socket(fd);
+		return -1;
+	}
+
+	ret = bind(fd, address, address_length);
+	if (ret < 0) {
+		SetSocketError(error);
+		close_socket(fd);
+		return -1;
+	}
+
+	ret = listen(fd, backlog);
+	if (ret < 0) {
+		SetSocketError(error);
+		error.AddPrefix("listen() failed: ");
+		close_socket(fd);
+		return -1;
+	}
+
+#ifdef HAVE_STRUCT_UCRED
+	setsockopt(fd, SOL_SOCKET, SO_PASSCRED,
+		   (const char *) &reuse, sizeof(reuse));
+#endif
+
+	return fd;
+}
+
+int
+socket_keepalive(int fd)
+{
+	const int reuse = 1;
+
+	return setsockopt(fd, SOL_SOCKET, SO_KEEPALIVE,
+			  (const char *)&reuse, sizeof(reuse));
+}
diff --git a/src/system/SocketUtil.hxx b/src/system/SocketUtil.hxx
new file mode 100644
index 000000000..5e582ec0d
--- /dev/null
+++ b/src/system/SocketUtil.hxx
@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+/*
+ * This library provides easy helper functions for working with
+ * sockets.
+ *
+ */
+
+#ifndef MPD_SOCKET_UTIL_HXX
+#define MPD_SOCKET_UTIL_HXX
+
+#include <stddef.h>
+
+struct sockaddr;
+class Error;
+
+/**
+ * Creates a socket listening on the specified address.  This is a
+ * shortcut for socket(), bind() and listen().
+ *
+ * @param domain the socket domain, e.g. PF_INET6
+ * @param type the socket type, e.g. SOCK_STREAM
+ * @param protocol the protocol, usually 0 to let the kernel choose
+ * @param address the address to listen on
+ * @param address_length the size of #address
+ * @param backlog the backlog parameter for the listen() system call
+ * @param error location to store the error occurring, or NULL to
+ * ignore errors
+ * @return the socket file descriptor or -1 on error
+ */
+int
+socket_bind_listen(int domain, int type, int protocol,
+		   const struct sockaddr *address, size_t address_length,
+		   int backlog,
+		   Error &error);
+
+int
+socket_keepalive(int fd);
+
+#endif
diff --git a/src/clock.c b/src/system/clock.c
index d987aed48..d987aed48 100644
--- a/src/clock.c
+++ b/src/system/clock.c
diff --git a/src/system/clock.h b/src/system/clock.h
new file mode 100644
index 000000000..c98b9a652
--- /dev/null
+++ b/src/system/clock.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2003-2012 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_CLOCK_H
+#define MPD_CLOCK_H
+
+#include "gcc.h"
+
+#include <stdint.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Returns the value of a monotonic clock in milliseconds.
+ */
+gcc_pure
+unsigned
+monotonic_clock_ms(void);
+
+/**
+ * Returns the value of a monotonic clock in microseconds.
+ */
+gcc_pure
+uint64_t
+monotonic_clock_us(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/src/system/fd_util.c b/src/system/fd_util.c
new file mode 100644
index 000000000..17976a5ee
--- /dev/null
+++ b/src/system/fd_util.c
@@ -0,0 +1,353 @@
+/*
+ * Copyright (C) 2003-2011 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - 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.
+ *
+ * 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 FOUNDATION 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.
+ */
+
+#include "config.h" /* must be first for large file support */
+#include "fd_util.h"
+
+#if !defined(_GNU_SOURCE) && (defined(HAVE_PIPE2) || defined(HAVE_ACCEPT4))
+#define _GNU_SOURCE
+#endif
+
+#include <assert.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#ifdef WIN32
+#include <ws2tcpip.h>
+#include <winsock2.h>
+#else
+#include <sys/socket.h>
+#endif
+
+#ifdef HAVE_INOTIFY_INIT
+#include <sys/inotify.h>
+#endif
+
+#ifdef USE_EVENTFD
+#include <sys/eventfd.h>
+#endif
+
+#ifndef WIN32
+
+static int
+fd_mask_flags(int fd, int and_mask, int xor_mask)
+{
+	int ret;
+
+	assert(fd >= 0);
+
+	ret = fcntl(fd, F_GETFD, 0);
+	if (ret < 0)
+		return ret;
+
+	return fcntl(fd, F_SETFD, (ret & and_mask) ^ xor_mask);
+}
+
+#endif /* !WIN32 */
+
+static int
+fd_set_cloexec(int fd, bool enable)
+{
+#ifndef WIN32
+	return fd_mask_flags(fd, ~FD_CLOEXEC, enable ? FD_CLOEXEC : 0);
+#else
+	(void)fd;
+	(void)enable;
+
+	return 0;
+#endif
+}
+
+/**
+ * Enables non-blocking mode for the specified file descriptor.  On
+ * WIN32, this function only works for sockets.
+ */
+static int
+fd_set_nonblock(int fd)
+{
+#ifdef WIN32
+	u_long val = 1;
+	return ioctlsocket(fd, FIONBIO, &val);
+#else
+	int flags;
+
+	assert(fd >= 0);
+
+	flags = fcntl(fd, F_GETFL);
+	if (flags < 0)
+		return flags;
+
+	return fcntl(fd, F_SETFL, flags | O_NONBLOCK);
+#endif
+}
+
+int
+dup_cloexec(int oldfd)
+{
+	int newfd = dup(oldfd);
+	if (newfd >= 0)
+		fd_set_nonblock(newfd);
+
+	return newfd;
+}
+
+int
+open_cloexec(const char *path_fs, int flags, int mode)
+{
+	int fd;
+
+#ifdef O_CLOEXEC
+	flags |= O_CLOEXEC;
+#endif
+
+#ifdef O_NOCTTY
+	flags |= O_NOCTTY;
+#endif
+
+	fd = open(path_fs, flags, mode);
+	if (fd >= 0)
+		fd_set_cloexec(fd, true);
+
+	return fd;
+}
+
+int
+pipe_cloexec(int fd[2])
+{
+#ifdef WIN32
+	return _pipe(fd, 512, _O_BINARY);
+#else
+	int ret;
+
+#ifdef HAVE_PIPE2
+	ret = pipe2(fd, O_CLOEXEC);
+	if (ret >= 0 || errno != ENOSYS)
+		return ret;
+#endif
+
+	ret = pipe(fd);
+	if (ret >= 0) {
+		fd_set_cloexec(fd[0], true);
+		fd_set_cloexec(fd[1], true);
+	}
+
+	return ret;
+#endif
+}
+
+int
+pipe_cloexec_nonblock(int fd[2])
+{
+#ifdef WIN32
+	return _pipe(fd, 512, _O_BINARY);
+#else
+	int ret;
+
+#ifdef HAVE_PIPE2
+	ret = pipe2(fd, O_CLOEXEC|O_NONBLOCK);
+	if (ret >= 0 || errno != ENOSYS)
+		return ret;
+#endif
+
+	ret = pipe(fd);
+	if (ret >= 0) {
+		fd_set_cloexec(fd[0], true);
+		fd_set_cloexec(fd[1], true);
+
+		fd_set_nonblock(fd[0]);
+		fd_set_nonblock(fd[1]);
+	}
+
+	return ret;
+#endif
+}
+
+#ifndef WIN32
+
+int
+socketpair_cloexec(int domain, int type, int protocol, int sv[2])
+{
+	int ret;
+
+#ifdef SOCK_CLOEXEC
+	ret = socketpair(domain, type | SOCK_CLOEXEC, protocol, sv);
+	if (ret >= 0 || errno != EINVAL)
+		return ret;
+#endif
+
+	ret = socketpair(domain, type, protocol, sv);
+	if (ret >= 0) {
+		fd_set_cloexec(sv[0], true);
+		fd_set_cloexec(sv[1], true);
+	}
+
+	return ret;
+}
+
+int
+socketpair_cloexec_nonblock(int domain, int type, int protocol, int sv[2])
+{
+	int ret;
+
+#if defined(SOCK_CLOEXEC) && defined(SOCK_NONBLOCK)
+	ret = socketpair(domain, type | SOCK_CLOEXEC | SOCK_NONBLOCK, protocol,
+			 sv);
+	if (ret >= 0 || errno != EINVAL)
+		return ret;
+#endif
+
+	ret = socketpair(domain, type, protocol, sv);
+	if (ret >= 0) {
+		fd_set_cloexec(sv[0], true);
+		fd_set_nonblock(sv[0]);
+		fd_set_cloexec(sv[1], true);
+		fd_set_nonblock(sv[1]);
+	}
+
+	return ret;
+}
+
+#endif
+
+int
+socket_cloexec_nonblock(int domain, int type, int protocol)
+{
+	int fd;
+
+#if defined(SOCK_CLOEXEC) && defined(SOCK_NONBLOCK)
+	fd = socket(domain, type | SOCK_CLOEXEC | SOCK_NONBLOCK, protocol);
+	if (fd >= 0 || errno != EINVAL)
+		return fd;
+#endif
+
+	fd = socket(domain, type, protocol);
+	if (fd >= 0) {
+		fd_set_cloexec(fd, true);
+		fd_set_nonblock(fd);
+	}
+
+	return fd;
+}
+
+int
+accept_cloexec_nonblock(int fd, struct sockaddr *address,
+			size_t *address_length_r)
+{
+	int ret;
+	socklen_t address_length = *address_length_r;
+
+#ifdef HAVE_ACCEPT4
+	ret = accept4(fd, address, &address_length,
+		      SOCK_CLOEXEC|SOCK_NONBLOCK);
+	if (ret >= 0 || errno != ENOSYS) {
+		if (ret >= 0)
+			*address_length_r = address_length;
+
+		return ret;
+	}
+#endif
+
+	ret = accept(fd, address, &address_length);
+	if (ret >= 0) {
+		fd_set_cloexec(ret, true);
+		fd_set_nonblock(ret);
+		*address_length_r = address_length;
+	}
+
+	return ret;
+}
+
+#ifndef WIN32
+
+ssize_t
+recvmsg_cloexec(int sockfd, struct msghdr *msg, int flags)
+{
+#ifdef MSG_CMSG_CLOEXEC
+	flags |= MSG_CMSG_CLOEXEC;
+#endif
+
+	ssize_t result = recvmsg(sockfd, msg, flags);
+	if (result >= 0) {
+		struct cmsghdr *cmsg = CMSG_FIRSTHDR(msg);
+		while (cmsg != NULL) {
+			if (cmsg->cmsg_type == SCM_RIGHTS) {
+				const int *fd_p = (const int *)CMSG_DATA(cmsg);
+				fd_set_cloexec(*fd_p, true);
+			}
+
+			cmsg = CMSG_NXTHDR(msg, cmsg);
+		}
+	}
+
+	return result;
+}
+
+#endif
+
+#ifdef HAVE_INOTIFY_INIT
+
+int
+inotify_init_cloexec(void)
+{
+	int fd;
+
+#ifdef HAVE_INOTIFY_INIT1
+	fd = inotify_init1(IN_CLOEXEC);
+	if (fd >= 0 || errno != ENOSYS)
+		return fd;
+#endif
+
+	fd = inotify_init();
+	if (fd >= 0)
+		fd_set_cloexec(fd, true);
+
+	return fd;
+}
+
+#endif
+
+#ifdef USE_EVENTFD
+
+int
+eventfd_cloexec_nonblock(unsigned initval, int flags)
+{
+	return eventfd(initval, flags | EFD_CLOEXEC | EFD_NONBLOCK);
+}
+
+#endif
+
+int
+close_socket(int fd)
+{
+#ifdef WIN32
+	return closesocket(fd);
+#else
+	return close(fd);
+#endif
+}
diff --git a/src/system/fd_util.h b/src/system/fd_util.h
new file mode 100644
index 000000000..9003b1616
--- /dev/null
+++ b/src/system/fd_util.h
@@ -0,0 +1,168 @@
+/*
+ * Copyright (C) 2003-2011 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *
+ * - 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.
+ *
+ * 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 FOUNDATION 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.
+ */
+
+/*
+ * This library provides easy helper functions for working with file
+ * descriptors.  It has wrappers for taking advantage of Linux 2.6
+ * specific features like O_CLOEXEC.
+ *
+ */
+
+#ifndef FD_UTIL_H
+#define FD_UTIL_H
+
+#include "check.h"
+
+#include <stdbool.h>
+#include <stddef.h>
+
+#ifndef WIN32
+#if !defined(_GNU_SOURCE) && (defined(HAVE_PIPE2) || defined(HAVE_ACCEPT4))
+#define _GNU_SOURCE
+#endif
+
+#include <sys/types.h>
+#endif
+
+struct sockaddr;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Wrapper for dup(), which sets the CLOEXEC flag on the new
+ * descriptor.
+ */
+int
+dup_cloexec(int oldfd);
+
+/**
+ * Wrapper for open(), which sets the CLOEXEC flag (atomically if
+ * supported by the OS).
+ */
+int
+open_cloexec(const char *path_fs, int flags, int mode);
+
+/**
+ * Wrapper for pipe(), which sets the CLOEXEC flag (atomically if
+ * supported by the OS).
+ */
+int
+pipe_cloexec(int fd[2]);
+
+/**
+ * Wrapper for pipe(), which sets the CLOEXEC flag (atomically if
+ * supported by the OS).
+ *
+ * On systems that supports it (everybody except for Windows), it also
+ * sets the NONBLOCK flag.
+ */
+int
+pipe_cloexec_nonblock(int fd[2]);
+
+#ifndef WIN32
+
+/**
+ * Wrapper for socketpair(), which sets the CLOEXEC flag (atomically
+ * if supported by the OS).
+ */
+int
+socketpair_cloexec(int domain, int type, int protocol, int sv[2]);
+
+/**
+ * Wrapper for socketpair(), which sets the flags CLOEXEC and NONBLOCK
+ * (atomically if supported by the OS).
+ */
+int
+socketpair_cloexec_nonblock(int domain, int type, int protocol, int sv[2]);
+
+#endif
+
+/**
+ * Wrapper for socket(), which sets the CLOEXEC and the NONBLOCK flag
+ * (atomically if supported by the OS).
+ */
+int
+socket_cloexec_nonblock(int domain, int type, int protocol);
+
+/**
+ * Wrapper for accept(), which sets the CLOEXEC and the NONBLOCK flags
+ * (atomically if supported by the OS).
+ */
+int
+accept_cloexec_nonblock(int fd, struct sockaddr *address,
+			size_t *address_length_r);
+
+
+#ifndef WIN32
+
+struct msghdr;
+
+/**
+ * Wrapper for recvmsg(), which sets the CLOEXEC flag (atomically if
+ * supported by the OS).
+ */
+ssize_t
+recvmsg_cloexec(int sockfd, struct msghdr *msg, int flags);
+
+#endif
+
+#ifdef HAVE_INOTIFY_INIT
+
+/**
+ * Wrapper for inotify_init(), which sets the CLOEXEC flag (atomically
+ * if supported by the OS).
+ */
+int
+inotify_init_cloexec(void);
+
+#endif
+
+#ifdef USE_EVENTFD
+
+/**
+ * Wrapper for eventfd() which sets the flags CLOEXEC and NONBLOCK
+ * flag (atomically if supported by the OS).
+ */
+int
+eventfd_cloexec_nonblock(unsigned initval, int flags);
+
+#endif
+
+/**
+ * Portable wrapper for close(); use closesocket() on WIN32/WinSock.
+ */
+int
+close_socket(int fd);
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif