Relocate source fiiles to src/ subdirectory

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

src/Makefile.am

@@ -0,0 +1,14 @@
+lib_LTLIBRARIES     = libuev.la
+libuev_la_SOURCES   = uev.c io.c timer.c signal.c cron.c
+libuev_la_CPPFLAGS  = -D_GNU_SOURCE -D_TIME_BITS=64
+libuev_la_CFLAGS    = -W -Wall -Wextra
+libuev_la_LDFLAGS   = $(AM_LDFLAGS) -version-info 1:2:0
+
+noinst_PROGRAMS     = bench
+bench_CPPFLAGS      = -D_GNU_SOURCE
+bench_LDADD         = libuev.la
+
+pkgconfigdir        = $(libdir)/pkgconfig
+pkgincludedir       = $(includedir)/uev
+pkgconfig_DATA      = libuev.pc
+pkginclude_HEADERS  = uev.h private.h queue.h

src/bench.c

@@ -0,0 +1,236 @@
+/*
+ * Copyright 2003 Niels Provos <provos@citi.umich.edu>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ *
+ *
+ * Mon 03/10/2003 - Modified by Davide Libenzi <davidel@xmailserver.org>
+ *
+ *     Added chain event propagation to improve the sensitivity of
+ *     the measure respect to the event loop efficency.
+ *
+ * Sun 04/08/2013 - Modified by Joachim Nilsson <troglobit@gmail.com>
+ *
+ *     Adaptations for libuEv, no libev/libevent API wrappers available.
+ *     Reindent to Linux coding style
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#else
+#define USE_PIPES
+#endif
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/resource.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#include "uev.h"
+
+#define UNUSED(arg) arg __attribute__ ((unused))
+
+typedef struct {
+	int index;
+} myarg_t;
+
+static int num_pipes, num_active, num_writes;
+static int timers, count, writes, fired;
+static myarg_t *args;
+static int *pipes;
+static uev_t *evio;
+static uev_t *evto;
+
+static void read_cb(uev_t *w, void *arg, int UNUSED(events))
+{
+	int idx, widx;
+	u_char ch;
+	myarg_t *m = arg;
+
+	idx  = m->index;
+	widx = idx + 1;
+	if (timers)
+		uev_timer_set(&evto[idx], 10000 + drand48() * 1000, 0);
+
+	count += read(w->fd, &ch, sizeof(ch));
+	if (writes) {
+		if (widx >= num_pipes)
+			widx -= num_pipes;
+
+		if (write(pipes[2 * widx + 1], "e", 1) < 0) {
+			perror("write()");
+			abort();
+		}
+
+		writes--;
+		fired++;
+	}
+}
+
+static void timer_cb(uev_t UNUSED(*w), void UNUSED(*arg), int UNUSED(events))
+{
+	/* nop */
+}
+
+static struct timeval *run_once(uev_ctx_t *ctx)
+{
+	int *cp, i, space;
+	static struct timeval ta, ts, te;
+
+	gettimeofday(&ta, NULL);
+	for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
+		uev_io_set(&evio[i], cp[0], UEV_READ);
+
+		if (timers)
+			uev_timer_set(&evto[i], 10000 + drand48() * 1000, 0);
+	}
+
+	uev_run(ctx, UEV_ONCE | UEV_NONBLOCK);
+
+	fired = 0;
+	space = num_pipes / num_active;
+	space = space * 2;
+	for (i = 0; i < num_active; i++, fired++) {
+		if (write(pipes[i * space + 1], "e", 1) < 0) {
+			perror("write()");
+			abort();
+		}
+	}
+
+	count = 0;
+	writes = num_writes;
+	{
+		int xcount = 0;
+
+		gettimeofday(&ts, NULL);
+
+		do {
+			uev_run(ctx, UEV_ONCE | UEV_NONBLOCK);
+			xcount++;
+		} while (count != fired);
+
+		gettimeofday(&te, NULL);
+
+		if (xcount != count)
+			fprintf(stderr, "Xcount: %d, Rcount: %d\n", xcount, count);
+	}
+
+	timersub(&te, &ta, &ta);
+	timersub(&te, &ts, &ts);
+	fprintf(stdout, "%8ld %8ld\n",
+		ta.tv_sec * 1000000L + ta.tv_usec,
+		ts.tv_sec * 1000000L + ts.tv_usec);
+
+	return &te;
+}
+
+int main(int argc, char **argv)
+{
+	struct rlimit rl;
+	int i, c;
+	int *cp;
+	uev_ctx_t ctx;
+	extern char *optarg;
+
+	num_pipes = 100;
+	num_active = 1;
+	num_writes = num_pipes;
+	while ((c = getopt(argc, argv, "a:n:tw:")) != -1) {
+		switch (c) {
+		case 'a':
+			num_active = atoi(optarg);
+			break;
+
+		case 'n':
+			num_pipes = atoi(optarg);
+			break;
+
+		case 't':
+			timers = 1;
+			break;
+
+		case 'w':
+			num_writes = atoi(optarg);
+			break;
+
+		default:
+			fprintf(stderr, "Illegal argument \"%c\"\n", c);
+			return 1;
+		}
+	}
+
+	rl.rlim_cur = rl.rlim_max = num_pipes * 3 + 50;
+	if (setrlimit(RLIMIT_NOFILE, &rl) == -1) {
+		perror("setrlimit");
+		return 1;
+	}
+
+	args   = calloc(num_pipes, sizeof(myarg_t));
+	evio   = calloc(num_pipes, sizeof(uev_t));
+	evto   = calloc(num_pipes, sizeof(uev_t));
+	pipes  = calloc(num_pipes * 2, sizeof(int));
+	if (!args || !evio || !evto || !pipes) {
+		perror("calloc");
+		return 1;
+	}
+
+	uev_init(&ctx);
+
+	for (cp = pipes, i = 0; i < num_pipes; i++, cp += 2) {
+		if (timers)
+			uev_timer_init(&ctx, &evto[i], timer_cb, NULL, 0, 0);
+		args[i].index = i;
+
+#ifdef USE_PIPES
+		if (pipe2(cp, O_NONBLOCK) == -1) {
+#else
+		if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, 0, cp) == -1) {
+#endif
+			perror("pipe");
+			exit(1);
+		}
+
+		uev_io_init(&ctx, &evio[i], read_cb, &args[i], cp[0], UEV_READ);
+	}
+
+	for (i = 0; i < 2; i++)
+		run_once(&ctx);
+
+	return 0;
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/cron.c

@@ -0,0 +1,165 @@
+/* libuEv - Micro event loop library
+ *
+ * Copyright (c) 2012       Flemming Madsen <flemming!madsen()madsensoft!dk>
+ * Copyright (c) 2013-2016  Joachim Nilsson <troglobit()gmail!com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <errno.h>
+#include <string.h>		/* memset() */
+#include <sys/timerfd.h>
+#include <unistd.h>		/* close(), read() */
+
+#include "uev.h"
+
+/* Missing defines in GLIBC <= 2.24 */
+#ifndef TFD_TIMER_CANCEL_ON_SET
+#define TFD_TIMER_CANCEL_ON_SET (1 << 1)
+#endif
+#ifndef TFD_SETTIME_FLAGS
+#define TFD_SETTIME_FLAGS (TFD_TIMER_ABSTIME | TFD_TIMER_CANCEL_ON_SET)
+#endif
+
+
+/**
+ * Create and start an at/cron job watcher
+ * @param ctx      A valid libuEv context
+ * @param w        Pointer to an uev_t watcher
+ * @param cb       Callback function for cron job
+ * @param arg      Optional callback argument
+ * @param when     First point in time to call @param cb
+ * @param interval For an at job this is zero, for cron the offset interval
+ *
+ * For at jobs set @param interval to zero and only use @param when.  For
+ * cron jobs, set @param interval to the offset.  E.g., if the job should
+ * run every five minutes set the @param tm_min of struct tm to five.
+ *
+ * Use mktime() to create the time_t arguments.  The special value zero
+ * may be used for @param when to denote 'now', where 'now' is when the
+ * event loop is started.  You can also treat time_t simply as a signed
+ * integer.  E.g., set @param interval to 3600 to create a cron job that
+ * runs every hour.
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_cron_init(uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, time_t when, time_t interval)
+{
+	int fd;
+
+	if (when < 0 || interval < 0) {
+		errno = ERANGE;
+		return -1;
+	}
+
+	fd = timerfd_create(CLOCK_REALTIME, TFD_NONBLOCK | TFD_CLOEXEC);
+	if (fd < 0)
+		return -1;
+
+	if (uev_watcher_init(ctx, w, UEV_CRON_TYPE, cb, arg, fd, UEV_READ))
+		goto exit;
+
+	if (uev_cron_set(w, when, interval)) {
+		uev_watcher_stop(w);
+	exit:
+		close(fd);
+		return -1;
+	}
+
+	return 0;
+}
+
+/**
+ * Reset an at/cron job watcher
+ * @param w        Watcher to reset
+ * @param when     First point in time to call @param cb
+ * @param interval For an at job this is zero, for cron the offset interval
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_cron_set(uev_t *w, time_t when, time_t interval)
+{
+	/* Every watcher must be registered to a context */
+	if (!w || !w->ctx) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (when < 0 || interval < 0) {
+		errno = ERANGE;
+		return -1;
+	}
+
+	/* Handle stopped timers */
+	if (w->fd < 0) {
+		/* Timer already stopped */
+		if (!when && !interval)
+			return 0;
+
+		/* Remove from internal list */
+		LIST_REMOVE(w, link);
+
+		if (uev_cron_init(w->ctx, w, (uev_cb_t *)w->cb, w->arg, when, interval))
+			return -1;
+	}
+
+	w->u.c.when     = when;
+	w->u.c.interval = interval;
+
+	if (w->ctx->running) {
+		struct itimerspec time;
+
+		memset(&time, 0, sizeof(time));
+		time.it_value.tv_sec    = when;
+		time.it_interval.tv_sec = interval;
+		if (timerfd_settime(w->fd, TFD_SETTIME_FLAGS, &time, NULL) < 0)
+			return 1;
+	}
+
+	return uev_watcher_start(w);
+}
+
+/**
+ * Start a stopped at/cron job watcher
+ * @param w  Watcher to start (again)
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_cron_start(uev_t *w)
+{
+	return uev_timer_start(w);
+}
+
+/**
+ * Stop and unregister an at/cron job watcher
+ * @param w  Watcher to stop
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_cron_stop(uev_t *w)
+{
+	return uev_timer_stop(w);
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/io.c

@@ -0,0 +1,100 @@
+/* libuEv - Micro event loop library
+ *
+ * Copyright (c) 2012       Flemming Madsen <flemming!madsen()madsensoft!dk>
+ * Copyright (c) 2013-2016  Joachim Nilsson <troglobit()gmail!com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <errno.h>
+#include "uev.h"
+
+
+/**
+ * Create an I/O watcher
+ * @param ctx     A valid libuEv context
+ * @param w       Pointer to an uev_t watcher
+ * @param cb      I/O callback
+ * @param arg     Optional callback argument
+ * @param fd      File descriptor to watch, or -1 to register an empty watcher
+ * @param events  Requested events to watch for, a mask of %UEV_READ, %UEV_WRITE and %UEV_PRI
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_io_init(uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int fd, int events)
+{
+	if (fd < 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (uev_watcher_init(ctx, w, UEV_IO_TYPE, cb, arg, fd, events))
+		return -1;
+
+	return uev_watcher_start(w);
+}
+
+/**
+ * Reset an I/O watcher
+ * @param w       Pointer to an uev_t watcher
+ * @param fd      New file descriptor to monitor
+ * @param events  Requested events to watch for, a mask of %UEV_READ and %UEV_WRITE
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_io_set(uev_t *w, int fd, int events)
+{
+
+	if ((events & UEV_ONESHOT) && w->active)
+		return uev_watcher_rearm(w);
+
+	/* Ignore any errors, only to clean up anything lingering ... */
+	uev_io_stop(w);
+
+	return uev_io_init(w->ctx, w, (uev_cb_t *)w->cb, w->arg, fd, events);
+}
+
+/**
+ * Start an I/O watcher
+ * @param w  Watcher to start (again)
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_io_start(uev_t *w)
+{
+	return uev_io_set(w, w->fd, w->events);
+}
+
+/**
+ * Stop an I/O watcher
+ * @param w  Watcher to stop
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_io_stop(uev_t *w)
+{
+	return uev_watcher_stop(w);
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/libuev.pc.in

@@ -0,0 +1,12 @@
+prefix=@prefix@
+exec_prefix=@exec_prefix@
+libdir=@libdir@
+includedir=@includedir@
+
+Name: @PACKAGE@
+Description: Simple event loop for Linux
+Version: @VERSION@
+Requires:
+Libs: -L${libdir} -luev
+Cflags: -I${includedir}
+

src/private.h

@@ -0,0 +1,99 @@
+/* libuEv - Private methods and data types, do not use directly!
+ *
+ * Copyright (c) 2012       Flemming Madsen <flemming!madsen()madsensoft!dk>
+ * Copyright (c) 2013-2015  Joachim Nilsson <troglobit()gmail!com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef LIBUEV_PRIVATE_H_
+#define LIBUEV_PRIVATE_H_
+
+#include <stdio.h>
+#include <sys/epoll.h>
+#include "queue.h"	       /* OpenBSD queue.h > old GLIBC version */
+
+/* I/O, timer, or signal watcher */
+typedef enum {
+	UEV_CRON_TYPE = 1,
+	UEV_IO_TYPE,
+	UEV_SIGNAL_TYPE,
+	UEV_TIMER_TYPE,
+} uev_type_t;
+
+/* Event mask, used internally only. */
+#define UEV_EVENT_MASK  (UEV_READ | UEV_WRITE | UEV_PRI | UEV_HUP | UEV_RDHUP | UEV_EDGE | UEV_ONESHOT)
+
+/* Main libuEv context type */
+typedef struct {
+	int             running;
+	int             fd;     /* For epoll() */
+	uint32_t        errors;
+	LIST_HEAD(,uev) watchers;
+} uev_ctx_t;
+
+/* Forward declare due to dependencys, don't try this at home kids. */
+struct uev;
+
+/* This is used to hide all private data members in uev_t */
+#define uev_private_t                                           \
+	LIST_ENTRY(uev) link;   /* For queue.h linked list */   \
+								\
+	int             active;                                 \
+	int             events;                                 \
+								\
+	/* Watcher callback with optional argument */           \
+	void          (*cb)(struct uev *, void *, int);         \
+	void           *arg;                                    \
+								\
+	/* Arguments for different watchers */			\
+	union {							\
+		/* Cron watchers */				\
+		struct {					\
+			time_t when;				\
+			time_t interval;			\
+		} c;						\
+								\
+		/* Timer watchers, time in milliseconds */	\
+		struct {					\
+			int timeout;				\
+			int period;				\
+		} t;						\
+	} u;							\
+								\
+	/* Watcher type */					\
+	uev_type_t
+
+/* Internal API for dealing with generic watchers */
+int uev_watcher_init  (uev_ctx_t *ctx, struct uev *w, uev_type_t type,
+		       void (*cb)(struct uev *, void *, int), void *arg,
+		       int fd, int events);
+int uev_watcher_start (struct uev *w);
+int uev_watcher_stop  (struct uev *w);
+int uev_watcher_active(struct uev *w);
+int uev_watcher_rearm (struct uev *w);
+
+#endif /* LIBUEV_PRIVATE_H_ */
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/queue.h

@@ -0,0 +1,648 @@
+/*	$OpenBSD: queue.h,v 1.38 2013/07/03 15:05:21 fgsch Exp $	*/
+/*	$NetBSD: queue.h,v 1.11 1996/05/16 05:17:14 mycroft Exp $	*/
+
+/*
+ * Copyright (c) 1991, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. 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.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
+ *
+ *	@(#)queue.h	8.5 (Berkeley) 8/20/94
+ */
+
+#ifndef	_SYS_QUEUE_H_
+#define	_SYS_QUEUE_H_
+
+/*
+ * This file defines five types of data structures: singly-linked lists, 
+ * lists, simple queues, tail queues, and circular queues.
+ *
+ *
+ * A singly-linked list is headed by a single forward pointer. The elements
+ * are singly linked for minimum space and pointer manipulation overhead at
+ * the expense of O(n) removal for arbitrary elements. New elements can be
+ * added to the list after an existing element or at the head of the list.
+ * Elements being removed from the head of the list should use the explicit
+ * macro for this purpose for optimum efficiency. A singly-linked list may
+ * only be traversed in the forward direction.  Singly-linked lists are ideal
+ * for applications with large datasets and few or no removals or for
+ * implementing a LIFO queue.
+ *
+ * A list is headed by a single forward pointer (or an array of forward
+ * pointers for a hash table header). The elements are doubly linked
+ * so that an arbitrary element can be removed without a need to
+ * traverse the list. New elements can be added to the list before
+ * or after an existing element or at the head of the list. A list
+ * may only be traversed in the forward direction.
+ *
+ * A simple queue is headed by a pair of pointers, one the head of the
+ * list and the other to the tail of the list. The elements are singly
+ * linked to save space, so elements can only be removed from the
+ * head of the list. New elements can be added to the list before or after
+ * an existing element, at the head of the list, or at the end of the
+ * list. A simple queue may only be traversed in the forward direction.
+ *
+ * A tail queue is headed by a pair of pointers, one to the head of the
+ * list and the other to the tail of the list. The elements are doubly
+ * linked so that an arbitrary element can be removed without a need to
+ * traverse the list. New elements can be added to the list before or
+ * after an existing element, at the head of the list, or at the end of
+ * the list. A tail queue may be traversed in either direction.
+ *
+ * A circle queue is headed by a pair of pointers, one to the head of the
+ * list and the other to the tail of the list. The elements are doubly
+ * linked so that an arbitrary element can be removed without a need to
+ * traverse the list. New elements can be added to the list before or after
+ * an existing element, at the head of the list, or at the end of the list.
+ * A circle queue may be traversed in either direction, but has a more
+ * complex end of list detection.
+ *
+ * For details on the use of these macros, see the queue(3) manual page.
+ */
+
+#if defined(QUEUE_MACRO_DEBUG) || (defined(_KERNEL) && defined(DIAGNOSTIC))
+#define _Q_INVALIDATE(a) (a) = ((void *)-1)
+#else
+#define _Q_INVALIDATE(a)
+#endif
+
+/*
+ * Singly-linked List definitions.
+ */
+#define SLIST_HEAD(name, type)						\
+struct name {								\
+	struct type *slh_first;	/* first element */			\
+}
+ 
+#define	SLIST_HEAD_INITIALIZER(head)					\
+	{ NULL }
+ 
+#define SLIST_ENTRY(type)						\
+struct {								\
+	struct type *sle_next;	/* next element */			\
+}
+ 
+/*
+ * Singly-linked List access methods.
+ */
+#define	SLIST_FIRST(head)	((head)->slh_first)
+#define	SLIST_END(head)		NULL
+#define	SLIST_EMPTY(head)	(SLIST_FIRST(head) == SLIST_END(head))
+#define	SLIST_NEXT(elm, field)	((elm)->field.sle_next)
+
+#define	SLIST_FOREACH(var, head, field)					\
+	for((var) = SLIST_FIRST(head);					\
+	    (var) != SLIST_END(head);					\
+	    (var) = SLIST_NEXT(var, field))
+
+#define	SLIST_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = SLIST_FIRST(head);				\
+	    (var) && ((tvar) = SLIST_NEXT(var, field), 1);		\
+	    (var) = (tvar))
+
+/*
+ * Singly-linked List functions.
+ */
+#define	SLIST_INIT(head) {						\
+	SLIST_FIRST(head) = SLIST_END(head);				\
+}
+
+#define	SLIST_INSERT_AFTER(slistelm, elm, field) do {			\
+	(elm)->field.sle_next = (slistelm)->field.sle_next;		\
+	(slistelm)->field.sle_next = (elm);				\
+} while (0)
+
+#define	SLIST_INSERT_HEAD(head, elm, field) do {			\
+	(elm)->field.sle_next = (head)->slh_first;			\
+	(head)->slh_first = (elm);					\
+} while (0)
+
+#define	SLIST_REMOVE_AFTER(elm, field) do {				\
+	(elm)->field.sle_next = (elm)->field.sle_next->field.sle_next;	\
+} while (0)
+
+#define	SLIST_REMOVE_HEAD(head, field) do {				\
+	(head)->slh_first = (head)->slh_first->field.sle_next;		\
+} while (0)
+
+#define SLIST_REMOVE(head, elm, type, field) do {			\
+	if ((head)->slh_first == (elm)) {				\
+		SLIST_REMOVE_HEAD((head), field);			\
+	} else {							\
+		struct type *curelm = (head)->slh_first;		\
+									\
+		while (curelm->field.sle_next != (elm))			\
+			curelm = curelm->field.sle_next;		\
+		curelm->field.sle_next =				\
+		    curelm->field.sle_next->field.sle_next;		\
+		_Q_INVALIDATE((elm)->field.sle_next);			\
+	}								\
+} while (0)
+
+/*
+ * List definitions.
+ */
+#define LIST_HEAD(name, type)						\
+struct name {								\
+	struct type *lh_first;	/* first element */			\
+}
+
+#define LIST_HEAD_INITIALIZER(head)					\
+	{ NULL }
+
+#define LIST_ENTRY(type)						\
+struct {								\
+	struct type *le_next;	/* next element */			\
+	struct type **le_prev;	/* address of previous next element */	\
+}
+
+/*
+ * List access methods
+ */
+#define	LIST_FIRST(head)		((head)->lh_first)
+#define	LIST_END(head)			NULL
+#define	LIST_EMPTY(head)		(LIST_FIRST(head) == LIST_END(head))
+#define	LIST_NEXT(elm, field)		((elm)->field.le_next)
+
+#define LIST_FOREACH(var, head, field)					\
+	for((var) = LIST_FIRST(head);					\
+	    (var)!= LIST_END(head);					\
+	    (var) = LIST_NEXT(var, field))
+
+#define	LIST_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = LIST_FIRST(head);				\
+	    (var) && ((tvar) = LIST_NEXT(var, field), 1);		\
+	    (var) = (tvar))
+
+/*
+ * List functions.
+ */
+#define	LIST_INIT(head) do {						\
+	LIST_FIRST(head) = LIST_END(head);				\
+} while (0)
+
+#define LIST_INSERT_AFTER(listelm, elm, field) do {			\
+	if (((elm)->field.le_next = (listelm)->field.le_next) != NULL)	\
+		(listelm)->field.le_next->field.le_prev =		\
+		    &(elm)->field.le_next;				\
+	(listelm)->field.le_next = (elm);				\
+	(elm)->field.le_prev = &(listelm)->field.le_next;		\
+} while (0)
+
+#define	LIST_INSERT_BEFORE(listelm, elm, field) do {			\
+	(elm)->field.le_prev = (listelm)->field.le_prev;		\
+	(elm)->field.le_next = (listelm);				\
+	*(listelm)->field.le_prev = (elm);				\
+	(listelm)->field.le_prev = &(elm)->field.le_next;		\
+} while (0)
+
+#define LIST_INSERT_HEAD(head, elm, field) do {				\
+	if (((elm)->field.le_next = (head)->lh_first) != NULL)		\
+		(head)->lh_first->field.le_prev = &(elm)->field.le_next;\
+	(head)->lh_first = (elm);					\
+	(elm)->field.le_prev = &(head)->lh_first;			\
+} while (0)
+
+#define LIST_REMOVE(elm, field) do {					\
+	if ((elm)->field.le_next != NULL)				\
+		(elm)->field.le_next->field.le_prev =			\
+		    (elm)->field.le_prev;				\
+	*(elm)->field.le_prev = (elm)->field.le_next;			\
+	_Q_INVALIDATE((elm)->field.le_prev);				\
+	_Q_INVALIDATE((elm)->field.le_next);				\
+} while (0)
+
+#define LIST_REPLACE(elm, elm2, field) do {				\
+	if (((elm2)->field.le_next = (elm)->field.le_next) != NULL)	\
+		(elm2)->field.le_next->field.le_prev =			\
+		    &(elm2)->field.le_next;				\
+	(elm2)->field.le_prev = (elm)->field.le_prev;			\
+	*(elm2)->field.le_prev = (elm2);				\
+	_Q_INVALIDATE((elm)->field.le_prev);				\
+	_Q_INVALIDATE((elm)->field.le_next);				\
+} while (0)
+
+/*
+ * Simple queue definitions.
+ */
+#define SIMPLEQ_HEAD(name, type)					\
+struct name {								\
+	struct type *sqh_first;	/* first element */			\
+	struct type **sqh_last;	/* addr of last next element */		\
+}
+
+#define SIMPLEQ_HEAD_INITIALIZER(head)					\
+	{ NULL, &(head).sqh_first }
+
+#define SIMPLEQ_ENTRY(type)						\
+struct {								\
+	struct type *sqe_next;	/* next element */			\
+}
+
+/*
+ * Simple queue access methods.
+ */
+#define	SIMPLEQ_FIRST(head)	    ((head)->sqh_first)
+#define	SIMPLEQ_END(head)	    NULL
+#define	SIMPLEQ_EMPTY(head)	    (SIMPLEQ_FIRST(head) == SIMPLEQ_END(head))
+#define	SIMPLEQ_NEXT(elm, field)    ((elm)->field.sqe_next)
+
+#define SIMPLEQ_FOREACH(var, head, field)				\
+	for((var) = SIMPLEQ_FIRST(head);				\
+	    (var) != SIMPLEQ_END(head);					\
+	    (var) = SIMPLEQ_NEXT(var, field))
+
+#define	SIMPLEQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = SIMPLEQ_FIRST(head);				\
+	    (var) && ((tvar) = SIMPLEQ_NEXT(var, field), 1);		\
+	    (var) = (tvar))
+
+/*
+ * Simple queue functions.
+ */
+#define	SIMPLEQ_INIT(head) do {						\
+	(head)->sqh_first = NULL;					\
+	(head)->sqh_last = &(head)->sqh_first;				\
+} while (0)
+
+#define SIMPLEQ_INSERT_HEAD(head, elm, field) do {			\
+	if (((elm)->field.sqe_next = (head)->sqh_first) == NULL)	\
+		(head)->sqh_last = &(elm)->field.sqe_next;		\
+	(head)->sqh_first = (elm);					\
+} while (0)
+
+#define SIMPLEQ_INSERT_TAIL(head, elm, field) do {			\
+	(elm)->field.sqe_next = NULL;					\
+	*(head)->sqh_last = (elm);					\
+	(head)->sqh_last = &(elm)->field.sqe_next;			\
+} while (0)
+
+#define SIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do {		\
+	if (((elm)->field.sqe_next = (listelm)->field.sqe_next) == NULL)\
+		(head)->sqh_last = &(elm)->field.sqe_next;		\
+	(listelm)->field.sqe_next = (elm);				\
+} while (0)
+
+#define SIMPLEQ_REMOVE_HEAD(head, field) do {			\
+	if (((head)->sqh_first = (head)->sqh_first->field.sqe_next) == NULL) \
+		(head)->sqh_last = &(head)->sqh_first;			\
+} while (0)
+
+#define SIMPLEQ_REMOVE_AFTER(head, elm, field) do {			\
+	if (((elm)->field.sqe_next = (elm)->field.sqe_next->field.sqe_next) \
+	    == NULL)							\
+		(head)->sqh_last = &(elm)->field.sqe_next;		\
+} while (0)
+
+/*
+ * XOR Simple queue definitions.
+ */
+#define XSIMPLEQ_HEAD(name, type)					\
+struct name {								\
+	struct type *sqx_first;	/* first element */			\
+	struct type **sqx_last;	/* addr of last next element */		\
+	unsigned long sqx_cookie;					\
+}
+
+#define XSIMPLEQ_ENTRY(type)						\
+struct {								\
+	struct type *sqx_next;	/* next element */			\
+}
+
+/*
+ * XOR Simple queue access methods.
+ */
+#define XSIMPLEQ_XOR(head, ptr)	    ((__typeof(ptr))((head)->sqx_cookie ^ \
+					(unsigned long)(ptr)))
+#define	XSIMPLEQ_FIRST(head)	    XSIMPLEQ_XOR(head, ((head)->sqx_first))
+#define	XSIMPLEQ_END(head)	    NULL
+#define	XSIMPLEQ_EMPTY(head)	    (XSIMPLEQ_FIRST(head) == XSIMPLEQ_END(head))
+#define	XSIMPLEQ_NEXT(head, elm, field)    XSIMPLEQ_XOR(head, ((elm)->field.sqx_next))
+
+
+#define XSIMPLEQ_FOREACH(var, head, field)				\
+	for ((var) = XSIMPLEQ_FIRST(head);				\
+	    (var) != XSIMPLEQ_END(head);				\
+	    (var) = XSIMPLEQ_NEXT(head, var, field))
+
+#define	XSIMPLEQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = XSIMPLEQ_FIRST(head);				\
+	    (var) && ((tvar) = XSIMPLEQ_NEXT(head, var, field), 1);	\
+	    (var) = (tvar))
+
+/*
+ * XOR Simple queue functions.
+ */
+#define	XSIMPLEQ_INIT(head) do {					\
+	arc4random_buf(&(head)->sqx_cookie, sizeof((head)->sqx_cookie)); \
+	(head)->sqx_first = XSIMPLEQ_XOR(head, NULL);			\
+	(head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first);	\
+} while (0)
+
+#define XSIMPLEQ_INSERT_HEAD(head, elm, field) do {			\
+	if (((elm)->field.sqx_next = (head)->sqx_first) ==		\
+	    XSIMPLEQ_XOR(head, NULL))					\
+		(head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \
+	(head)->sqx_first = XSIMPLEQ_XOR(head, (elm));			\
+} while (0)
+
+#define XSIMPLEQ_INSERT_TAIL(head, elm, field) do {			\
+	(elm)->field.sqx_next = XSIMPLEQ_XOR(head, NULL);		\
+	*(XSIMPLEQ_XOR(head, (head)->sqx_last)) = XSIMPLEQ_XOR(head, (elm)); \
+	(head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next);	\
+} while (0)
+
+#define XSIMPLEQ_INSERT_AFTER(head, listelm, elm, field) do {		\
+	if (((elm)->field.sqx_next = (listelm)->field.sqx_next) ==	\
+	    XSIMPLEQ_XOR(head, NULL))					\
+		(head)->sqx_last = XSIMPLEQ_XOR(head, &(elm)->field.sqx_next); \
+	(listelm)->field.sqx_next = XSIMPLEQ_XOR(head, (elm));		\
+} while (0)
+
+#define XSIMPLEQ_REMOVE_HEAD(head, field) do {				\
+	if (((head)->sqx_first = XSIMPLEQ_XOR(head,			\
+	    (head)->sqx_first)->field.sqx_next) == XSIMPLEQ_XOR(head, NULL)) \
+		(head)->sqx_last = XSIMPLEQ_XOR(head, &(head)->sqx_first); \
+} while (0)
+
+#define XSIMPLEQ_REMOVE_AFTER(head, elm, field) do {			\
+	if (((elm)->field.sqx_next = XSIMPLEQ_XOR(head,			\
+	    (elm)->field.sqx_next)->field.sqx_next)			\
+	    == XSIMPLEQ_XOR(head, NULL))				\
+		(head)->sqx_last = 					\
+		    XSIMPLEQ_XOR(head, &(elm)->field.sqx_next);		\
+} while (0)
+
+		    
+/*
+ * Tail queue definitions.
+ */
+#define TAILQ_HEAD(name, type)						\
+struct name {								\
+	struct type *tqh_first;	/* first element */			\
+	struct type **tqh_last;	/* addr of last next element */		\
+}
+
+#define TAILQ_HEAD_INITIALIZER(head)					\
+	{ NULL, &(head).tqh_first }
+
+#define TAILQ_ENTRY(type)						\
+struct {								\
+	struct type *tqe_next;	/* next element */			\
+	struct type **tqe_prev;	/* address of previous next element */	\
+}
+
+/* 
+ * tail queue access methods 
+ */
+#define	TAILQ_FIRST(head)		((head)->tqh_first)
+#define	TAILQ_END(head)			NULL
+#define	TAILQ_NEXT(elm, field)		((elm)->field.tqe_next)
+#define TAILQ_LAST(head, headname)					\
+	(*(((struct headname *)((head)->tqh_last))->tqh_last))
+/* XXX */
+#define TAILQ_PREV(elm, headname, field)				\
+	(*(((struct headname *)((elm)->field.tqe_prev))->tqh_last))
+#define	TAILQ_EMPTY(head)						\
+	(TAILQ_FIRST(head) == TAILQ_END(head))
+
+#define TAILQ_FOREACH(var, head, field)					\
+	for((var) = TAILQ_FIRST(head);					\
+	    (var) != TAILQ_END(head);					\
+	    (var) = TAILQ_NEXT(var, field))
+
+#define	TAILQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = TAILQ_FIRST(head);					\
+	    (var) != TAILQ_END(head) &&					\
+	    ((tvar) = TAILQ_NEXT(var, field), 1);			\
+	    (var) = (tvar))
+
+
+#define TAILQ_FOREACH_REVERSE(var, head, headname, field)		\
+	for((var) = TAILQ_LAST(head, headname);				\
+	    (var) != TAILQ_END(head);					\
+	    (var) = TAILQ_PREV(var, headname, field))
+
+#define	TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar)	\
+	for ((var) = TAILQ_LAST(head, headname);			\
+	    (var) != TAILQ_END(head) &&					\
+	    ((tvar) = TAILQ_PREV(var, headname, field), 1);		\
+	    (var) = (tvar))
+
+/*
+ * Tail queue functions.
+ */
+#define	TAILQ_INIT(head) do {						\
+	(head)->tqh_first = NULL;					\
+	(head)->tqh_last = &(head)->tqh_first;				\
+} while (0)
+
+#define TAILQ_INSERT_HEAD(head, elm, field) do {			\
+	if (((elm)->field.tqe_next = (head)->tqh_first) != NULL)	\
+		(head)->tqh_first->field.tqe_prev =			\
+		    &(elm)->field.tqe_next;				\
+	else								\
+		(head)->tqh_last = &(elm)->field.tqe_next;		\
+	(head)->tqh_first = (elm);					\
+	(elm)->field.tqe_prev = &(head)->tqh_first;			\
+} while (0)
+
+#define TAILQ_INSERT_TAIL(head, elm, field) do {			\
+	(elm)->field.tqe_next = NULL;					\
+	(elm)->field.tqe_prev = (head)->tqh_last;			\
+	*(head)->tqh_last = (elm);					\
+	(head)->tqh_last = &(elm)->field.tqe_next;			\
+} while (0)
+
+#define TAILQ_INSERT_AFTER(head, listelm, elm, field) do {		\
+	if (((elm)->field.tqe_next = (listelm)->field.tqe_next) != NULL)\
+		(elm)->field.tqe_next->field.tqe_prev =			\
+		    &(elm)->field.tqe_next;				\
+	else								\
+		(head)->tqh_last = &(elm)->field.tqe_next;		\
+	(listelm)->field.tqe_next = (elm);				\
+	(elm)->field.tqe_prev = &(listelm)->field.tqe_next;		\
+} while (0)
+
+#define	TAILQ_INSERT_BEFORE(listelm, elm, field) do {			\
+	(elm)->field.tqe_prev = (listelm)->field.tqe_prev;		\
+	(elm)->field.tqe_next = (listelm);				\
+	*(listelm)->field.tqe_prev = (elm);				\
+	(listelm)->field.tqe_prev = &(elm)->field.tqe_next;		\
+} while (0)
+
+#define TAILQ_REMOVE(head, elm, field) do {				\
+	if (((elm)->field.tqe_next) != NULL)				\
+		(elm)->field.tqe_next->field.tqe_prev =			\
+		    (elm)->field.tqe_prev;				\
+	else								\
+		(head)->tqh_last = (elm)->field.tqe_prev;		\
+	*(elm)->field.tqe_prev = (elm)->field.tqe_next;			\
+	_Q_INVALIDATE((elm)->field.tqe_prev);				\
+	_Q_INVALIDATE((elm)->field.tqe_next);				\
+} while (0)
+
+#define TAILQ_REPLACE(head, elm, elm2, field) do {			\
+	if (((elm2)->field.tqe_next = (elm)->field.tqe_next) != NULL)	\
+		(elm2)->field.tqe_next->field.tqe_prev =		\
+		    &(elm2)->field.tqe_next;				\
+	else								\
+		(head)->tqh_last = &(elm2)->field.tqe_next;		\
+	(elm2)->field.tqe_prev = (elm)->field.tqe_prev;			\
+	*(elm2)->field.tqe_prev = (elm2);				\
+	_Q_INVALIDATE((elm)->field.tqe_prev);				\
+	_Q_INVALIDATE((elm)->field.tqe_next);				\
+} while (0)
+
+/*
+ * Circular queue definitions.
+ */
+#define CIRCLEQ_HEAD(name, type)					\
+struct name {								\
+	struct type *cqh_first;		/* first element */		\
+	struct type *cqh_last;		/* last element */		\
+}
+
+#define CIRCLEQ_HEAD_INITIALIZER(head)					\
+	{ CIRCLEQ_END(&head), CIRCLEQ_END(&head) }
+
+#define CIRCLEQ_ENTRY(type)						\
+struct {								\
+	struct type *cqe_next;		/* next element */		\
+	struct type *cqe_prev;		/* previous element */		\
+}
+
+/*
+ * Circular queue access methods 
+ */
+#define	CIRCLEQ_FIRST(head)		((head)->cqh_first)
+#define	CIRCLEQ_LAST(head)		((head)->cqh_last)
+#define	CIRCLEQ_END(head)		((void *)(head))
+#define	CIRCLEQ_NEXT(elm, field)	((elm)->field.cqe_next)
+#define	CIRCLEQ_PREV(elm, field)	((elm)->field.cqe_prev)
+#define	CIRCLEQ_EMPTY(head)						\
+	(CIRCLEQ_FIRST(head) == CIRCLEQ_END(head))
+
+#define CIRCLEQ_FOREACH(var, head, field)				\
+	for((var) = CIRCLEQ_FIRST(head);				\
+	    (var) != CIRCLEQ_END(head);					\
+	    (var) = CIRCLEQ_NEXT(var, field))
+
+#define	CIRCLEQ_FOREACH_SAFE(var, head, field, tvar)			\
+	for ((var) = CIRCLEQ_FIRST(head);				\
+	    (var) != CIRCLEQ_END(head) &&				\
+	    ((tvar) = CIRCLEQ_NEXT(var, field), 1);			\
+	    (var) = (tvar))
+
+#define CIRCLEQ_FOREACH_REVERSE(var, head, field)			\
+	for((var) = CIRCLEQ_LAST(head);					\
+	    (var) != CIRCLEQ_END(head);					\
+	    (var) = CIRCLEQ_PREV(var, field))
+
+#define	CIRCLEQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar)	\
+	for ((var) = CIRCLEQ_LAST(head, headname);			\
+	    (var) != CIRCLEQ_END(head) && 				\
+	    ((tvar) = CIRCLEQ_PREV(var, headname, field), 1);		\
+	    (var) = (tvar))
+
+/*
+ * Circular queue functions.
+ */
+#define	CIRCLEQ_INIT(head) do {						\
+	(head)->cqh_first = CIRCLEQ_END(head);				\
+	(head)->cqh_last = CIRCLEQ_END(head);				\
+} while (0)
+
+#define CIRCLEQ_INSERT_AFTER(head, listelm, elm, field) do {		\
+	(elm)->field.cqe_next = (listelm)->field.cqe_next;		\
+	(elm)->field.cqe_prev = (listelm);				\
+	if ((listelm)->field.cqe_next == CIRCLEQ_END(head))		\
+		(head)->cqh_last = (elm);				\
+	else								\
+		(listelm)->field.cqe_next->field.cqe_prev = (elm);	\
+	(listelm)->field.cqe_next = (elm);				\
+} while (0)
+
+#define CIRCLEQ_INSERT_BEFORE(head, listelm, elm, field) do {		\
+	(elm)->field.cqe_next = (listelm);				\
+	(elm)->field.cqe_prev = (listelm)->field.cqe_prev;		\
+	if ((listelm)->field.cqe_prev == CIRCLEQ_END(head))		\
+		(head)->cqh_first = (elm);				\
+	else								\
+		(listelm)->field.cqe_prev->field.cqe_next = (elm);	\
+	(listelm)->field.cqe_prev = (elm);				\
+} while (0)
+
+#define CIRCLEQ_INSERT_HEAD(head, elm, field) do {			\
+	(elm)->field.cqe_next = (head)->cqh_first;			\
+	(elm)->field.cqe_prev = CIRCLEQ_END(head);			\
+	if ((head)->cqh_last == CIRCLEQ_END(head))			\
+		(head)->cqh_last = (elm);				\
+	else								\
+		(head)->cqh_first->field.cqe_prev = (elm);		\
+	(head)->cqh_first = (elm);					\
+} while (0)
+
+#define CIRCLEQ_INSERT_TAIL(head, elm, field) do {			\
+	(elm)->field.cqe_next = CIRCLEQ_END(head);			\
+	(elm)->field.cqe_prev = (head)->cqh_last;			\
+	if ((head)->cqh_first == CIRCLEQ_END(head))			\
+		(head)->cqh_first = (elm);				\
+	else								\
+		(head)->cqh_last->field.cqe_next = (elm);		\
+	(head)->cqh_last = (elm);					\
+} while (0)
+
+#define	CIRCLEQ_REMOVE(head, elm, field) do {				\
+	if ((elm)->field.cqe_next == CIRCLEQ_END(head))			\
+		(head)->cqh_last = (elm)->field.cqe_prev;		\
+	else								\
+		(elm)->field.cqe_next->field.cqe_prev =			\
+		    (elm)->field.cqe_prev;				\
+	if ((elm)->field.cqe_prev == CIRCLEQ_END(head))			\
+		(head)->cqh_first = (elm)->field.cqe_next;		\
+	else								\
+		(elm)->field.cqe_prev->field.cqe_next =			\
+		    (elm)->field.cqe_next;				\
+	_Q_INVALIDATE((elm)->field.cqe_prev);				\
+	_Q_INVALIDATE((elm)->field.cqe_next);				\
+} while (0)
+
+#define CIRCLEQ_REPLACE(head, elm, elm2, field) do {			\
+	if (((elm2)->field.cqe_next = (elm)->field.cqe_next) ==		\
+	    CIRCLEQ_END(head))						\
+		(head)->cqh_last = (elm2);				\
+	else								\
+		(elm2)->field.cqe_next->field.cqe_prev = (elm2);	\
+	if (((elm2)->field.cqe_prev = (elm)->field.cqe_prev) ==		\
+	    CIRCLEQ_END(head))						\
+		(head)->cqh_first = (elm2);				\
+	else								\
+		(elm2)->field.cqe_prev->field.cqe_next = (elm2);	\
+	_Q_INVALIDATE((elm)->field.cqe_prev);				\
+	_Q_INVALIDATE((elm)->field.cqe_next);				\
+} while (0)
+
+#endif	/* !_SYS_QUEUE_H_ */

src/signal.c

@@ -0,0 +1,157 @@
+/* libuEv - Micro event loop library
+ *
+ * Copyright (c) 2012       Flemming Madsen <flemming!madsen()madsensoft!dk>
+ * Copyright (c) 2013-2016  Joachim Nilsson <troglobit()gmail!com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <errno.h>
+#include <signal.h>
+#include <sys/signalfd.h>
+#include <unistd.h>		/* close(), read() */
+
+#include "uev.h"
+
+
+/**
+ * Create a signal watcher
+ * @param ctx    A valid libuEv context
+ * @param w      Pointer to an uev_t watcher
+ * @param cb     Timer callback
+ * @param arg    Optional callback argument
+ * @param signo  Signal to watch for
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_signal_init(uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int signo)
+{
+	int fd;
+	sigset_t mask;
+
+	if (!w || !ctx) {
+		errno = EINVAL;
+		return -1;
+	}
+	w->fd = -1;
+
+	sigemptyset(&mask);
+	fd = signalfd(-1, &mask, SFD_NONBLOCK | SFD_CLOEXEC);
+	if (fd < 0)
+		return -1;
+
+	if (uev_watcher_init(ctx, w, UEV_SIGNAL_TYPE, cb, arg, fd, UEV_READ))
+		goto exit;
+
+	if (uev_signal_set(w, signo)) {
+		uev_watcher_stop(w);
+	exit:
+		close(fd);
+		return -1;
+	}
+
+	return 0;
+}
+
+/**
+ * Reset a signal watcher
+ * @param w      Watcher to reset
+ * @param signo  New signal to watch for
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_signal_set(uev_t *w, int signo)
+{
+	sigset_t mask;
+
+	/* Every watcher must be registered to a context */
+	if (!w || !w->ctx) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	/* Remember for callbacks and start/stop */
+	w->signo = signo;
+
+	/* Handle stopped signal watchers */
+	if (w->fd < 0) {
+		/* Remove from internal list */
+		LIST_REMOVE(w, link);
+
+		if (uev_signal_init(w->ctx, w, (uev_cb_t *)w->cb, w->arg, signo))
+			return -1;
+	}
+
+	sigemptyset(&mask);
+	sigaddset(&mask, signo);
+
+	/* Block signals so that they aren't handled
+	   according to their default dispositions */
+	if (sigprocmask(SIG_BLOCK, &mask, NULL) == -1)
+		return -1;
+
+	if (signalfd(w->fd, &mask, SFD_NONBLOCK) < 0)
+		return -1;
+
+	return uev_watcher_start(w);
+}
+
+
+/**
+ * Start a stopped signal watcher
+ * @param w  Watcher to start (again)
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_signal_start(uev_t *w)
+{
+	if (!w) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (-1 != w->fd)
+		uev_signal_stop(w);
+
+	return uev_signal_set(w, w->signo);
+}
+
+/**
+ * Stop a signal watcher
+ * @param w  Watcher to stop
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_signal_stop(uev_t *w)
+{
+	if (uev_watcher_stop(w))
+		return -1;
+
+	close(w->fd);
+	w->fd = -1;
+
+	return 0;
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/timer.c

@@ -0,0 +1,186 @@
+/* libuEv - Micro event loop library
+ *
+ * Copyright (c) 2012       Flemming Madsen <flemming!madsen()madsensoft!dk>
+ * Copyright (c) 2013-2016  Joachim Nilsson <troglobit()gmail!com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <errno.h>
+#include <sys/timerfd.h>
+#include <unistd.h>		/* close(), read() */
+
+#include "uev.h"
+
+
+static void msec2tspec(int msec, struct timespec *ts)
+{
+	if (msec) {
+		ts->tv_sec  =  msec / 1000;
+		ts->tv_nsec = (msec % 1000) * 1000000;
+	} else {
+		ts->tv_sec  = 0;
+		ts->tv_nsec = 0;
+	}
+}
+
+/**
+ * Create and start a timer watcher
+ * @param ctx      A valid libuEv context
+ * @param w        Pointer to an uev_t watcher
+ * @param cb       Callback function
+ * @param arg      Optional callback argument
+ * @param timeout  Timeout in milliseconds before @param cb is called
+ * @param period   For periodic timers this is the period time that @param timeout is reset to
+ *
+ * For one-shot timers you set @param period to zero and only use @param
+ * timeout.  For periodic timers you likely set @param timeout to either
+ * zero, to call it as soon as the event loop starts, or to the same
+ * value as @param period.  When the timer expires, the @param cb
+ * is called, with the optional @param arg argument.  A non-periodic
+ * timer ends its life there, while a periodic task's @param timeout is
+ * reset to the @param period and restarted.
+ *
+ * A timer is automatically started if the event loop is already
+ * running, otherwise it is kept on hold until triggered by calling
+ * uev_run().
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_timer_init(uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int timeout, int period)
+{
+	int fd;
+
+	if (timeout < 0 || period < 0) {
+		errno = ERANGE;
+		return -1;
+	}
+
+	fd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK | TFD_CLOEXEC);
+	if (fd < 0)
+		return -1;
+
+	if (uev_watcher_init(ctx, w, UEV_TIMER_TYPE, cb, arg, fd, UEV_READ))
+		goto exit;
+
+	if (uev_timer_set(w, timeout, period)) {
+		uev_watcher_stop(w);
+	exit:
+		close(fd);
+		return -1;
+	}
+
+	return 0;
+}
+
+/**
+ * Reset a timer
+ * @param w        Watcher to reset
+ * @param timeout  Timeout in milliseconds before @param cb is called
+ * @param period   For periodic timers this is the period time that @param timeout is reset to
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_timer_set(uev_t *w, int timeout, int period)
+{
+	/* Every watcher must be registered to a context */
+	if (!w || !w->ctx) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (timeout < 0 || period < 0) {
+		errno = ERANGE;
+		return -1;
+	}
+
+	/* Handle stopped timers */
+	if (w->fd < 0) {
+		/* Timer already stopped */
+		if (!timeout && !period)
+			return 0;
+
+		/* Remove from internal list */
+		LIST_REMOVE(w, link);
+
+		if (uev_timer_init(w->ctx, w, (uev_cb_t *)w->cb, w->arg, timeout, period))
+			return -1;
+	}
+
+	w->u.t.timeout = timeout;
+	w->u.t.period  = period;
+
+	if (w->ctx->running) {
+		struct itimerspec time;
+
+		msec2tspec(timeout, &time.it_value);
+		msec2tspec(period, &time.it_interval);
+		if (timerfd_settime(w->fd, 0, &time, NULL) < 0)
+			return 1;
+	}
+
+	return uev_watcher_start(w);
+}
+
+/**
+ * Start a stopped timer watcher
+ * @param w  Watcher to start (again)
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_timer_start(uev_t *w)
+{
+	if (!w) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (-1 != w->fd)
+		uev_watcher_stop(w);
+
+	return uev_timer_set(w, w->u.t.timeout, w->u.t.period);
+}
+
+/**
+ * Stop and unregister a timer watcher
+ * @param w  Watcher to stop
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_timer_stop(uev_t *w)
+{
+	/* Stop kernel timer */
+	uev_timer_set(w, 0, 0);
+
+	if (uev_watcher_stop(w))
+		return -1;
+
+	/* Close timerfd, will have to be reopened again on reset */
+	close(w->fd);
+	w->fd = -1;
+
+	return 0;
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/uev.c

@@ -0,0 +1,372 @@
+/* libuEv - Micro event loop library
+ *
+ * Copyright (c) 2012       Flemming Madsen <flemming!madsen()madsensoft!dk>
+ * Copyright (c) 2013-2016  Joachim Nilsson <troglobit()gmail!com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <errno.h>
+#include <fcntl.h>		/* O_CLOEXEC */
+#include <string.h>		/* memset() */
+#include <sys/epoll.h>
+#include <sys/signalfd.h>	/* struct signalfd_siginfo */
+#include <unistd.h>		/* close(), read() */
+
+#include "uev.h"
+
+#define UNUSED(arg) arg __attribute__ ((unused))
+
+
+static int _init(uev_ctx_t *ctx, int close_old)
+{
+	int fd;
+
+	fd = epoll_create1(EPOLL_CLOEXEC);
+	if (fd < 0)
+		return -1;
+
+	if (close_old)
+		close(ctx->fd);
+
+	ctx->fd = fd;
+
+	return 0;
+}
+
+/* Simple check if a descriptor is still valid in the kernel */
+static int is_valid_fd(int fd)
+{
+    return fcntl(fd, F_GETFL) != -1 || errno != EBADF;
+}
+
+/* Private to libuEv, do not use directly! */
+int uev_watcher_init(uev_ctx_t *ctx, uev_t *w, uev_type_t type, uev_cb_t *cb, void *arg, int fd, int events)
+{
+	if (!ctx || !w) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	w->ctx    = ctx;
+	w->type   = type;
+	w->active = 0;
+	w->fd     = fd;
+	w->cb     = cb;
+	w->arg    = arg;
+	w->events = events;
+
+	return 0;
+}
+
+/* Private to libuEv, do not use directly! */
+int uev_watcher_start(uev_t *w)
+{
+	struct epoll_event ev;
+
+	if (!w || w->fd < 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (w->active)
+		return 0;
+
+	ev.events   = w->events | EPOLLRDHUP;
+	ev.data.ptr = w;
+	if (epoll_ctl(w->ctx->fd, EPOLL_CTL_ADD, w->fd, &ev) < 0)
+		return -1;
+
+	w->active = 1;
+
+	/* Add to internal list for bookkeeping */
+	LIST_INSERT_HEAD(&w->ctx->watchers, w, link);
+
+	return 0;
+}
+
+/* Private to libuEv, do not use directly! */
+int uev_watcher_stop(uev_t *w)
+{
+	if (!w) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	if (!w->active)
+		return 0;
+
+	w->active = 0;
+
+	/* Remove from internal list */
+	LIST_REMOVE(w, link);
+
+	/* Remove from kernel */
+	if (epoll_ctl(w->ctx->fd, EPOLL_CTL_DEL, w->fd, NULL) < 0)
+		return -1;
+
+	return 0;
+}
+
+/* Private to libuEv, do not use directly! */
+int uev_watcher_active(uev_t *w)
+{
+	if (!w)
+		return 0;
+
+	return w->active;
+}
+
+/* Private to libuEv, do not use directly! */
+int uev_watcher_rearm(uev_t *w)
+{
+	struct epoll_event ev;
+
+	if (!w || w->fd < 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	ev.events   = w->events | EPOLLRDHUP;
+	ev.data.ptr = w;
+	if (epoll_ctl(w->ctx->fd, EPOLL_CTL_MOD, w->fd, &ev) < 0)
+		return -1;
+
+	return 0;
+}
+
+/**
+ * Create an event loop context
+ * @param ctx  Pointer to an uev_ctx_t context to be initialized
+ *
+ * @return POSIX OK(0) on success, or non-zero on error.
+ */
+int uev_init(uev_ctx_t *ctx)
+{
+	if (!ctx) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	memset(ctx, 0, sizeof(*ctx));
+	LIST_INIT(&ctx->watchers);
+
+	return _init(ctx, 0);
+}
+
+/**
+ * Terminate the event loop
+ * @param ctx  A valid libuEv context
+ *
+ * @return POSIX OK(0) or non-zero with @param errno set on error.
+ */
+int uev_exit(uev_ctx_t *ctx)
+{
+	if (!ctx) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	while (!LIST_EMPTY(&ctx->watchers)) {
+		uev_t *w = LIST_FIRST(&ctx->watchers);
+
+		/* Remove from internal list */
+		LIST_REMOVE(w, link);
+
+		if (!w->active)
+			continue;
+
+		switch (w->type) {
+		case UEV_CRON_TYPE:
+		case UEV_TIMER_TYPE:
+			uev_timer_stop(w);
+			break;
+
+		case UEV_SIGNAL_TYPE:
+			uev_signal_stop(w);
+			break;
+
+		case UEV_IO_TYPE:
+			uev_io_stop(w);
+			break;
+		}
+	}
+
+	ctx->running = 0;
+	close(ctx->fd);
+	ctx->fd = -1;
+
+	return 0;
+}
+
+/**
+ * Start the event loop
+ * @param ctx    A valid libuEv context
+ * @param flags  A mask of %UEV_ONCE and %UEV_NONBLOCK, or zero
+ *
+ * With @flags set to %UEV_ONCE the event loop returns after the first
+ * event has been served, useful for instance to set a timeout on a file
+ * descriptor.  If @flags also has the %UEV_NONBLOCK flag set the event
+ * loop will return immediately if no event is pending, useful when run
+ * inside another event loop.
+ *
+ * @return POSIX OK(0) upon successful termination of the event loop, or
+ * non-zero on error.
+ */
+int uev_run(uev_ctx_t *ctx, int flags)
+{
+	int result = 0, timeout = -1;
+	uev_t *w;
+
+        if (!ctx || ctx->fd < 0) {
+		errno = EINVAL;
+                return -1;
+	}
+
+	if (flags & UEV_NONBLOCK)
+		timeout = 0;
+
+	/* Start the event loop */
+	ctx->running = 1;
+
+	/* Start all dormant timers */
+	LIST_FOREACH(w, &ctx->watchers, link) {
+		if (UEV_CRON_TYPE == w->type)
+			uev_cron_set(w, w->u.c.when, w->u.c.interval);
+		if (UEV_TIMER_TYPE == w->type)
+			uev_timer_set(w, w->u.t.timeout, w->u.t.period);
+	}
+
+	while (ctx->running) {
+		int i, nfds;
+		struct epoll_event events[UEV_MAX_EVENTS];
+
+		while ((nfds = epoll_wait(ctx->fd, events, UEV_MAX_EVENTS, timeout)) < 0) {
+			if (!ctx->running)
+				break;
+
+			if (EINTR == errno)
+				continue; /* Signalled, try again */
+
+			/* Unrecoverable error, cleanup and exit with error. */
+			uev_exit(ctx);
+			return -1;
+		}
+
+		for (i = 0; ctx->running && i < nfds; i++) {
+			w = (uev_t *)events[i].data.ptr;
+
+			if (events[i].events & (EPOLLHUP | EPOLLERR)) {
+				ctx->errors++;
+
+				if (ctx->errors >= 42) {
+					uev_t *tmp, *retry = w;;
+
+					/* If not valid anymore, try to remove, ignore any errors. */
+					if (!is_valid_fd(w->fd))
+						uev_watcher_stop(w);
+
+					/* Must recreate epoll fd now ... */
+					if (_init(ctx, 1)) {
+						uev_exit(ctx);
+						return -2;
+					}
+
+					/* Restart watchers in new efd */
+					LIST_FOREACH_SAFE(w, &ctx->watchers, link, tmp) {
+						if (w->active) {
+							w->active = 0;
+							LIST_REMOVE(w, link);
+							uev_watcher_start(w);
+						}
+					}
+					uev_watcher_start(retry);
+
+					/* New efd, restart everything! */
+					ctx->errors = 0;
+					continue;
+				}
+			}
+
+			if (UEV_CRON_TYPE == w->type) {
+				uint64_t exp;
+
+				if (read(w->fd, &exp, sizeof(exp)) != sizeof(exp)) {
+					if (errno != ECANCELED) {
+						uev_exit(ctx);
+						return -3;
+					}
+
+					events[i].events = UEV_HUP;
+				}
+
+				if (!w->u.c.interval)
+					w->u.c.when = 0;
+				else
+					w->u.c.when += w->u.c.interval;
+			}
+
+			if (UEV_TIMER_TYPE == w->type) {
+				uint64_t exp;
+
+				if (read(w->fd, &exp, sizeof(exp)) != sizeof(exp)) {
+					uev_exit(ctx);
+					return -3;
+				}
+
+				if (!w->u.t.period)
+					w->u.t.timeout = 0;
+			}
+
+			if (UEV_SIGNAL_TYPE == w->type) {
+				struct signalfd_siginfo fdsi;
+				ssize_t sz = sizeof(fdsi);
+
+				if (read(w->fd, &fdsi, sz) != sz) {
+					uev_exit(ctx);
+					return -4;
+				}
+			}
+
+			if (w->cb)
+				w->cb(w, w->arg, events[i].events & UEV_EVENT_MASK);
+
+			if (UEV_CRON_TYPE == w->type) {
+				if (!w->u.c.when)
+					uev_timer_stop(w);
+			}
+			if (UEV_TIMER_TYPE == w->type) {
+				if (!w->u.t.timeout)
+					uev_timer_stop(w);
+			}
+		}
+
+		if ((flags & UEV_ONCE) || LIST_EMPTY(&ctx->watchers))
+			break;
+	}
+
+	return result;
+}
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

src/uev.h

@@ -0,0 +1,99 @@
+/* libuEv - Micro event loop library
+ *
+ * Copyright (c) 2012       Flemming Madsen <flemming!madsen()madsensoft!dk>
+ * Copyright (c) 2013-2015  Joachim Nilsson <troglobit()gmail!com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef LIBUEV_UEV_H_
+#define LIBUEV_UEV_H_
+
+#include "private.h"
+
+/* Max. number of simulateneous events */
+#define UEV_MAX_EVENTS  10
+
+/* I/O events, for signals and timers revents will always be UEV_READ */
+#define UEV_NONE        0
+#define UEV_READ        EPOLLIN
+#define UEV_WRITE       EPOLLOUT
+#define UEV_PRI         EPOLLPRI
+#define UEV_HUP         EPOLLHUP
+#define UEV_RDHUP       EPOLLRDHUP
+#define UEV_EDGE        EPOLLET
+#define UEV_ONESHOT     EPOLLONESHOT
+
+/* Run flags */
+#define UEV_ONCE        1
+#define UEV_NONBLOCK    2
+
+/* Macros */
+#define uev_io_active(w)     uev_watcher_active(w)
+#define uev_timer_active(w)  uev_watcher_active(w)
+#define uev_cron_active(w)   uev_watcher_active(w)
+#define uev_signal_active(w) uev_watcher_active(w)
+
+/* Event watcher */
+typedef struct uev {
+	/* Private data for libuEv internal engine */
+	uev_private_t   type;
+
+	/* Public data for users to reference  */
+	int             signo;
+	int             fd;
+	uev_ctx_t      *ctx;
+} uev_t;
+
+/* Generic callback for watchers */
+typedef void (uev_cb_t)(uev_t *w, void *arg, int events);
+
+/* Public interface */
+int uev_init           (uev_ctx_t *ctx);
+int uev_exit           (uev_ctx_t *ctx);
+int uev_run            (uev_ctx_t *ctx, int flags);
+
+int uev_io_init        (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int fd, int events);
+int uev_io_set         (uev_t *w, int fd, int events);
+int uev_io_start       (uev_t *w);
+int uev_io_stop        (uev_t *w);
+
+int uev_timer_init     (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int timeout, int period);
+int uev_timer_set      (uev_t *w, int timeout, int period);
+int uev_timer_start    (uev_t *w);
+int uev_timer_stop     (uev_t *w);
+
+int uev_cron_init      (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, time_t when, time_t interval);
+int uev_cron_set       (uev_t *w, time_t when, time_t interval);
+int uev_cron_start     (uev_t *w);
+int uev_cron_stop      (uev_t *w);
+
+int uev_signal_init    (uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int signo);
+int uev_signal_set     (uev_t *w, int signo);
+int uev_signal_start   (uev_t *w);
+int uev_signal_stop    (uev_t *w);
+
+#endif /* LIBUEV_UEV_H_ */
+
+/**
+ * Local Variables:
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */