Makefile.am: move sources to libsystem.a

11 files changed, 1340 insertions, 0 deletions

diff --git a/src/system/FatalError.cxx b/src/system/FatalError.cxx
new file mode 100644
index 000000000..30ddc50ea
--- /dev/null
+++ b/src/system/FatalError.cxx
@@ -0,0 +1,91 @@
+/*
+ * 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 "FatalError.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(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..3918e5fc1
--- /dev/null
+++ b/src/system/FatalError.hxx
@@ -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.
+ */
+
+#ifndef MPD_FATAL_ERROR_HXX
+#define MPD_FATAL_ERROR_HXX
+
+#include "gerror.h"
+#include "gcc.h"
+
+/**
+ * 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(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/SocketError.hxx b/src/system/SocketError.hxx
new file mode 100644
index 000000000..53a0c1d8f
--- /dev/null
+++ b/src/system/SocketError.hxx
@@ -0,0 +1,156 @@
+/*
+ * 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 <glib.h>
+
+#ifdef WIN32
+#include <winsock2.h>
+typedef DWORD socket_error_t;
+#else
+#include <errno.h>
+typedef int socket_error_t;
+#endif
+
+/**
+ * A GQuark for GError for socket I/O errors.  The code is an errno
+ * value (or WSAGetLastError() on Windows).
+ */
+gcc_const
+static inline GQuark
+SocketErrorQuark(void)
+{
+	return g_quark_from_static_string("socket");
+}
+
+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()) {
+		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
+	explicit SocketErrorMessage(socket_error_t code=GetSocketError())
+		:msg(g_strerror(code)) {}
+#endif
+
+	operator const char *() const {
+		return msg;
+	}
+};
+
+static inline void
+SetSocketError(GError **error_r, socket_error_t code)
+{
+#ifdef WIN32
+	if (error_r == NULL)
+		return;
+#endif
+
+	const SocketErrorMessage msg(code);
+	g_set_error_literal(error_r, SocketErrorQuark(), code, msg);
+}
+
+static inline void
+SetSocketError(GError **error_r)
+{
+	SetSocketError(error_r, GetSocketError());
+}
+
+gcc_malloc
+static inline GError *
+NewSocketError(socket_error_t code)
+{
+	const SocketErrorMessage msg(code);
+	return g_error_new_literal(SocketErrorQuark(), code, msg);
+}
+
+gcc_malloc
+static inline GError *
+NewSocketError()
+{
+	return NewSocketError(GetSocketError());
+}
+
+#endif
diff --git a/src/system/SocketUtil.cxx b/src/system/SocketUtil.cxx
new file mode 100644
index 000000000..dd7eb7dd2
--- /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,
+		   GError **error_r)
+{
+	int fd, ret;
+	const int reuse = 1;
+
+	fd = socket_cloexec_nonblock(domain, type, protocol);
+	if (fd < 0) {
+		SetSocketError(error_r);
+		g_prefix_error(error_r, "Failed to create socket: ");
+		return -1;
+	}
+
+	ret = setsockopt(fd, SOL_SOCKET, SO_REUSEADDR,
+			 (const char *) &reuse, sizeof(reuse));
+	if (ret < 0) {
+		SetSocketError(error_r);
+		g_prefix_error(error_r, "setsockopt() failed: ");
+		close_socket(fd);
+		return -1;
+	}
+
+	ret = bind(fd, address, address_length);
+	if (ret < 0) {
+		SetSocketError(error_r);
+		close_socket(fd);
+		return -1;
+	}
+
+	ret = listen(fd, backlog);
+	if (ret < 0) {
+		SetSocketError(error_r);
+		g_prefix_error(error_r, "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..3d0be78c4
--- /dev/null
+++ b/src/system/SocketUtil.hxx
@@ -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.
+ */
+
+/*
+ * This library provides easy helper functions for working with
+ * sockets.
+ *
+ */
+
+#ifndef MPD_SOCKET_UTIL_HXX
+#define MPD_SOCKET_UTIL_HXX
+
+#include "gerror.h"
+
+#include <stddef.h>
+
+struct sockaddr;
+
+/**
+ * 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,
+		   GError **error);
+
+int
+socket_keepalive(int fd);
+
+#endif
diff --git a/src/system/clock.c b/src/system/clock.c
new file mode 100644
index 000000000..d987aed48
--- /dev/null
+++ b/src/system/clock.c
@@ -0,0 +1,98 @@
+/*
+ * 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.
+ */
+
+#include "clock.h"
+
+#ifdef WIN32
+#include <windows.h>
+#elif defined(__APPLE__)
+#include <mach/mach_time.h>
+#else
+#include <time.h>
+#ifndef CLOCK_MONOTONIC
+#include <sys/time.h>
+#endif
+#endif
+
+unsigned
+monotonic_clock_ms(void)
+{
+#ifdef WIN32
+	return GetTickCount();
+#elif defined(__APPLE__) /* OS X does not define CLOCK_MONOTONIC */
+	static mach_timebase_info_data_t base;
+	if (base.denom == 0)
+		(void)mach_timebase_info(&base);
+
+	return (unsigned)((mach_absolute_time() * base.numer)
+			  / (1000000 * base.denom));
+#elif defined(CLOCK_MONOTONIC)
+	struct timespec ts;
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	return ts.tv_sec * 1000 + ts.tv_nsec / 1000000;
+#else
+	/* we have no monotonic clock, fall back to gettimeofday() */
+	struct timeval tv;
+	gettimeofday(&tv, 0);
+	return tv.tv_sec * 1000 + tv.tv_usec / 1000;
+#endif
+}
+
+uint64_t
+monotonic_clock_us(void)
+{
+#ifdef WIN32
+	LARGE_INTEGER l_value, l_frequency;
+
+	if (!QueryPerformanceCounter(&l_value) ||
+	    !QueryPerformanceFrequency(&l_frequency))
+		return 0;
+
+	uint64_t value = l_value.QuadPart;
+	uint64_t frequency = l_frequency.QuadPart;
+
+	if (frequency > 1000000) {
+		value *= 10000;
+		value /= frequency / 100;
+	} else if (frequency < 1000000) {
+		value *= 10000;
+		value /= frequency;
+		value *= 100;
+	}
+
+	return value;
+#elif defined(__APPLE__) /* OS X does not define CLOCK_MONOTONIC */
+	static mach_timebase_info_data_t base;
+	if (base.denom == 0)
+		(void)mach_timebase_info(&base);
+
+	return ((uint64_t)mach_absolute_time() * (uint64_t)base.numer)
+		/ (1000 * (uint64_t)base.denom);
+#elif defined(CLOCK_MONOTONIC)
+	struct timespec ts;
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	return (uint64_t)ts.tv_sec * 1000000 + (uint64_t)(ts.tv_nsec / 1000);
+#else
+	/* we have no monotonic clock, fall back to gettimeofday() */
+	struct timeval tv;
+	gettimeofday(&tv, 0);
+	return (uint64_t)tv.tv_sec * 1000 + (uint64_t)tv.tv_usec;
+#endif
+}
+
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
diff --git a/src/system/resolver.c b/src/system/resolver.c
new file mode 100644
index 000000000..243b7cd02
--- /dev/null
+++ b/src/system/resolver.c
@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) 2003-2011 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.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>
+
+char *
+sockaddr_to_string(const struct sockaddr *sa, size_t length, GError **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) {
+		g_set_error(error, g_quark_from_static_string("netdb"), ret,
+			    "%s", 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,
+		  GError **error_r)
+{
+	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) {
+		g_snprintf(buffer, sizeof(buffer), "%u", default_port);
+		port = buffer;
+	}
+
+	if ((flags & AI_PASSIVE) != 0 && strcmp(host, "*") == 0)
+		host = NULL;
+
+	const struct addrinfo hints = {
+		.ai_flags = flags,
+		.ai_family = AF_UNSPEC,
+		.ai_socktype = socktype,
+	};
+
+	struct addrinfo *ai;
+	int ret = getaddrinfo(host, port, &hints, &ai);
+	g_free(p);
+	if (ret != 0) {
+		g_set_error(error_r, resolver_quark(), ret,
+			    "Failed to look up '%s': %s",
+			    host_port, gai_strerror(ret));
+		return NULL;
+	}
+
+	return ai;
+}
diff --git a/src/system/resolver.h b/src/system/resolver.h
new file mode 100644
index 000000000..af14f5f23
--- /dev/null
+++ b/src/system/resolver.h
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2003-2011 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_H
+#define MPD_RESOLVER_H
+
+#include "gcc.h"
+
+#include <glib.h>
+
+struct sockaddr;
+struct addrinfo;
+
+gcc_const
+static inline GQuark
+resolver_quark(void)
+{
+	return g_quark_from_static_string("resolver");
+}
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * 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, GError **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,
+		  GError **error_r);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif