Update ChangeLog and bump version for v1.2.0 release.

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

.gitignore

@@ -1,6 +1,6 @@
 bench
 test
-.*.d
+*.d
 *.o
 *~
 libuev.a

.travis.yml

@@ -0,0 +1,21 @@
+# Travis CI integration -- https://travis-ci.org/troglobit/libuev
+language: c
+compiler:
+  - gcc
+
+env:
+  global:
+   # The next declaration is the encrypted COVERITY_SCAN_TOKEN, created
+   #   via the "travis encrypt" command using the project repo's public key
+   - secure: "ikQcWMCLFoxq0+wMiqrNT5HRn0d4e3AxuF8VzNUNFrk6jUvHIufC/OKvr8VWPTjCaAQXZjWfdQAAARUXzJV10WZ7xpiv5qt4bt26Qih2AwMPMJeUOYrqXgQqhTPBp05iLYpo4ybICteXRI3zKKUA1wkdDC0jyu3rl+Fbveekbe0="
+
+addons:
+  coverity_scan:
+    project:
+      name: "troglobit/libuev"
+      description: "libuEv | Simple event loop for Linux"
+    notification_email: troglobit@gmail.com
+    build_command: "make"
+    branch_pattern: dev
+
+script: make

AUTHORS

@@ -1,4 +1,4 @@
-Current maintainer of libuev:
+Current maintainer of libuEv:
         Joachim Nilsson <troglobit()gmail!com>
 
 Original LibUEvent author:

CHANGELOG

@@ -0,0 +1 @@
+CHANGELOG.md

CHANGELOG.md

@@ -0,0 +1,148 @@
+Change Log
+==========
+
+All notable changes to the project are documented in this file.
+
+
+[v1.2.0] - 2015-06-09
+---------------------
+
+API change in event callbacks and fix timers that never start.
+
+### Changes
+- Remove first `uev_ctx_t *` argument in callbacks, incompatible API
+  change!  Please update all your callbacks if you upgrade.
+
+### Fixes
+- Fix timers that accidentally broke in [v1.1.0].
+- Fixes to `bench.c`, it now actually listens to the pipe/socket.
+
+
+[v1.1.0] - 2015-03-04
+---------------------
+
+Massively improved error handling.
+
+### Changes
+- Handle case when user closes a descriptor *before* stopping a watcher.
+- Handle `EPOLLHUP` and `EPOLLERR`.  Restart `epoll(7)` descriptor and
+  all watchers when an error count reaches a MAX value -- handles stale
+  descriptors or cases when kernel does not notice updated descriptors.
+- Return error when stopping a watcher fails.
+- Update [README.md] with new `uev_*_start()` functions.
+- Bump dev version to 1.1 due to the number of significant changes.
+
+### Fixes
+- Remove `test.c` from `DISTFILES` in `Makefile`.  You need the
+  comeplete sources to build the examples now.  Thanks to @karasz for
+  the heads up on this and the musl libc issue with missing `queue.h`!
+- Fix broken link to [v1.0.5] in this file.
+
+
+[v1.0.5] - 2015-02-15
+---------------------
+
+### Changes
+- Add `uev_*_start()` functions.
+- Add slightly odd `examples/signal.c` example that utilises `fork()`
+  and causes segfault in child.
+- Renamed `main.c` to `uev.c`
+- Move examples to `examples/` subdirectory
+- Simplify automatic dependency calculation
+- Add [TODO.md] for wishlist items
+- Add [CHANGELOG.md], attempt to align with http://keepachangelog.com
+- Further updates to [README.md]
+
+
+[v1.0.4] - 2015-01-24
+---------------------
+
+Minor documentation and build fixes.
+
+Release mainly targeted for [Finit development](https://github.com/troglobit/finit/).
+
+### Changes
+* `test.c` has been simplified/clarified
+* Further updates to [README.md]
+* Minor update to Makefile, change how build progress is echoed
+
+
+[v1.0.3] - 2015-01-24
+---------------------
+
+This is a very minor release, with a strong focus on documentation. 
+
+### Changes
+- [README.md], massively updated
+- API documentation, updated
+- Travis CI integration added, https://travis-ci.org/troglobit/libuev
+- Coverity Scan integration, https://scan.coverity.com/projects/3846
+- Clang scan-build support added
+
+
+[v1.0.2] - 2015-01-07
+---------------------
+
+### Fixes
+- Fix broken `make dist` target in [v1.0.1].
+
+
+[v1.0.1] - 2015-01-07
+---------------------
+
+### Changes
+- Cleanup and rewrite of [README.md] after first audit by @vonj
+- Added API and example section to [README.md]
+- New [joystick.c] example added
+- `main.c:uev_run()`: Document mysterious flags parameter
+
+
+[v1.0.0] - 2013-08-06
+---------------------
+
+First release in the new guise and API.
+
+### Changes
+- Add support for timers, using `timerfd_*()` and `epoll()` API's
+- Add support for signals using `signalfd()` API
+- Convert to use BSD `sys/queue.h` API in GLIBC instead of homebrew
+  linked list implementation
+- Massive changes to code structure, API naming
+- Reindent to use Linux KNF
+- Change library name to libuev
+- Lua support removed
+- Make sure to state the [MIT license] correctly in all files
+- Import [Niels Provos]' `bench.c`, the [libev version]
+
+
+v0.0.1 - 2012-03-17
+-------------------
+
+[Initial announcement] of [libuevent] by [Flemming Madsen] to the Lua
+users mailing list.
+
+[UNRELEASED]: https://github.com/troglobit/libuev/compare/v1.2.0...HEAD
+[v1.2.0]: https://github.com/troglobit/libuev/compare/v1.1.0...v1.2.0
+[v1.1.0]: https://github.com/troglobit/libuev/compare/v1.0.5...v1.1.0
+[v1.0.5]: https://github.com/troglobit/libuev/compare/v1.0.4...v1.0.5
+[v1.0.4]: https://github.com/troglobit/libuev/compare/v1.0.3...v1.0.4
+[v1.0.3]: https://github.com/troglobit/libuev/compare/v1.0.2...v1.0.3
+[v1.0.2]: https://github.com/troglobit/libuev/compare/v1.0.1...v1.0.2
+[v1.0.1]: https://github.com/troglobit/libuev/compare/v1.0.0...v1.0.1
+[v1.0.0]: https://github.com/troglobit/libuev/compare/v0.0.1...v1.0.0
+[TODO.md]: https://github.com/troglobit/libuev/blob/master/TODO.md
+[README.md]: https://github.com/troglobit/libuev/blob/master/README.md
+[CHANGLOG.md]: https://github.com/troglobit/libuev/blob/master/CHANGELOG.md
+[joystick.c]: https://github.com/troglobit/libuev/blob/master/joystick.c
+[Niels Provos]: http://en.wikipedia.org/wiki/Niels_Provos
+[MIT license]: http://en.wikipedia.org/wiki/MIT_License
+[libev version]: http://libev.schmorp.de/bench.c
+[libuevent]: https://code.google.com/p/libuevent/
+[Flemming Madsen]: http://www.madsensoft.dk
+[Initial announcement]: http://lua-users.org/lists/lua-l/2012-03/msg00510.html
+
+<!--
+  -- Local Variables:
+  --  mode: markdown
+  -- End:
+  -->

LICENSE

@@ -1,24 +1,20 @@
-Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
-Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+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:
+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 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.
-
-For an explanation and background of the MIT license, see the Wikipedia
-article https://en.wikipedia.org/wiki/MIT_License
+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.

Makefile

@@ -1,7 +1,7 @@
-# -*-Makefile-*- for libuev
+# libuEv main build file
 #
-# Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
-# Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+# 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
@@ -22,10 +22,10 @@
 # TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 #
-.PHONY: all test clean
+.PHONY: all test clean joystick test examples bench
 
 #VERSION    = $(shell git tag -l | tail -1)
-VERSION    ?= 1.0.0
+VERSION    ?= 1.2.0
 NAME        = libuev
 PKG         = $(NAME)-$(VERSION)
 ARCHIVE     = $(PKG).tar.xz
@@ -33,42 +33,44 @@ ARCHIVE     = $(PKG).tar.xz
 CC         ?= $(CROSS)gcc
 AR         ?= $(CROSS)ar
 STRIP      ?= $(CROSS)strip
-CHECK      ?= sparse
-CFLAGS     += -fPIC -Os
+
+ifneq ($(STATIC), 1)
+CFLAGS     += -fPIC
+endif
+CFLAGS     += -Os
 CPPFLAGS   += -W -Wall -Werror
 ARFLAGS     = crus
-CHECK_FLAGS = -Wcast-to-as -Wdefault-bitfield-sign -Wdo-while -Wparen-string        \
-	      -Wptr-subtraction-blows -Wreturn-void -Wshadow -Wtypesign -Wbitwise   \
-	      -std=gnu99  -D__x86_64__ -D__LP64__ -I/usr/include/x86_64-linux-gnu
-JUNK        = *~ *.bak *.map .*.d DEADJOE *.gdb *.elf core core.*
+JUNK        = *~ *.bak *.map .*.d DEADJOE *.gdb *.elf core core.* *.html
 
+MAKEFLAGS   = --no-print-directory
+
+ROOTDIR    ?= $(shell pwd)
 LIBNAME     = $(NAME)
 prefix     ?= /usr/local
 libdir     ?= $(prefix)/lib
 datadir    ?= $(prefix)/share/doc/$(LIBNAME)
 incdir     ?= $(prefix)/include
-DISTFILES   = README LICENSE test.c
+DISTFILES   = README CHANGELOG TODO LICENSE
 HEADER      = uev.h
 
-OBJS       := main.o io.o timer.o signal.o
+OBJS       := uev.o io.o timer.o signal.o
 SRCS       := $(OBJS:.o=.c)
-DEPS       := $(addprefix .,$(SRCS:.c=.d))
+DEPS       := $(SRCS:.c=.d)
 VER         = 1
 SOLIB       = $(LIBNAME).so.$(VER)
 SYMLIB      = $(LIBNAME).so
 STATICLIB   = $(LIBNAME).a
+ifeq ($(STATIC), 1)
+TARGET      = $(STATICLIB)
+else
 TARGET      = $(STATICLIB) $(SOLIB)
+endif
 
-# Pattern rules
-.c.o:
-	@printf "  CC      $@\n"
-	@$(CC) $(CFLAGS) $(CPPFLAGS) -c -o $@ $<
+export STATICLIB JUNK ROOTDIR CFLAGS CPPFLAGS
 
-# Smart autodependecy generation via GCC -M.
-.%.d: %.c
-	@$(SHELL) -ec "$(CC) -MM $(CFLAGS) $(CPPFLAGS) $< 2>/dev/null \
-		| sed 's,.*: ,$*.o $@ : ,g' > $@; \
-                [ -s $@ ] || rm -f $@"
+# This magic trick looks like a comment, but works on BSD PMake
+#include <rules.mk>
+include rules.mk
 
 # Build rules
 all: $(TARGET)
@@ -83,9 +85,10 @@ $(STATICLIB): Makefile $(OBJS)
 
 install: strip
 	@install -d $(DESTDIR)$(libdir)
-	@install $(SOLIB) $(DESTDIR)$(prefix)/lib/$(SOLIB)
-	@install $(STATICLIB) $(DESTDIR)$(prefix)/lib/$(STATICLIB)
-	@ln -sf $(SOLIB) $(DESTDIR)$(prefix)/lib/$(SYMLIB)
+	@printf "  INSTALL $(DESTDIR)$(libdir)/$(TARGET)\n"
+	@install $(SOLIB) $(DESTDIR)$(libdir)/$(SOLIB)
+	@install $(STATICLIB) $(DESTDIR)$(libdir)/$(STATICLIB)
+	@ln -sf $(SOLIB) $(DESTDIR)$(libdir)/$(SYMLIB)
 	@install -d $(DESTDIR)$(incdir)
 	@install -m 0644 $(HEADER) $(DESTDIR)$(incdir)/$(HEADER)
 	@install -d $(DESTDIR)$(datadir)
@@ -103,32 +106,32 @@ strip: $(TARGET)
 	@$(STRIP) --strip-unneeded $(TARGET)
 	@size $(TARGET)
 
-test: Makefile test.o $(STATICLIB)
-	@printf "  TEST    %s\n" $(STATICLIB)
-	@$(CC) $(CPPFLAGS) -g -o test test.c $(STATICLIB) && ./test
+bench: Makefile $(STATICLIB)
+	@printf "  RUN     %s\n" $@
+	@$(CC) $(CPPFLAGS) -D_GNU_SOURCE -g -o bench bench.c $(STATICLIB) && ./bench
 
-bench: Makefile bench.o $(STATICLIB)
-	@printf "  BENCH   %s\n" $(STATICLIB)
-	@$(CC) $(CPPFLAGS) -g -o bench bench.c $(STATICLIB) && ./bench
+examples: all
+	@$(MAKE) -C examples
 
-check:
-	@$(CHECK) $(CHECK_FLAGS) $(CPPFLAGS) $(SRCS) bench.c
+test joystick:
+	@$(MAKE) -C examples $@
+
+# Runs Clang scan-build on the whole tree
+check: clean
+	@scan-build $(MAKE) all
 
 clean:
-	-@$(RM) $(TARGET) *.o test
+	-@$(MAKE) -C examples $@
+	-@$(RM) $(TARGET) *.o test joystick bench
 
 distclean: clean
+	-@$(MAKE) -C examples $@
 	-@$(RM) $(DEPS) $(JUNK)
 
 dist:
 	@echo "Building .xz tarball of $(PKG) in parent dir..."
-	git archive --format=tar --prefix=$(PKG)/ $(VERSION) | xz >../$(ARCHIVE)
+	git archive --format=tar --prefix=$(PKG)/ v$(VERSION) | xz >../$(ARCHIVE)
 	@(cd ..; md5sum $(ARCHIVE) | tee $(ARCHIVE).md5)
 
 # Include automatically generated rules
-ifneq ($(MAKECMDGOALS),clean)
-ifneq ($(MAKECMDGOALS),distclean)
 -include $(DEPS)
-endif
-endif
-

README.md

@@ -1,68 +1,302 @@
-libuev - Micro event loop library
-=================================
-
-The libuev library is a small event library in the style of libevent,
-the excellent libev and the venerable Xt(3) event loop.
-
-It is heavily modelled after the libev API, but will never be as
-portable to other UNIX systems.  The primary target of this project is
-modern embedded Linux systems.  You will need kernel and C-library
-support for epoll(7), timerfd and signalfd.
+libuEv | Simple event loop for Linux
+====================================
+[![Travis Status]][Travis] [![Coverity Status]][Coverity Scan]
 
 
-Usage
------
+Table of Contents
+-----------------
 
-The user initializes an event context to which timer and I/O stream
-watchers are registered.  A typical application then enters the event
-loop that will only return at program termination.
+* [Introduction](#introduction)
+* [API](#api)
+* [Example](#example)
+* [Build & Install](#build--install)
+* [Origin & References](#origin--references)
 
 
-The C API
----------
+Introduction
+------------
 
-The typical application will do the following steps
+> “Why an event loop, why not use threads?”
 
-   1. Prepare an event context with `uev_init()`
-   2. Register callbacks with `uev_io_init()` and `uev_timer_init()`
-   3. Enter the event loop with `uev_run()`
+With the advent of light-weight processes (threads) programmers these
+days have a [golden hammer](http://c2.com/cgi/wiki?GoldenHammer) they
+often swing without consideration.  Event loops and non-blocking I/O is
+often a far easier approach, as well as less error prone.
 
-**Note:** Make sure to use non-blocking stream I/O!
+The purpose of many applications is, with a little logic sprinkled on
+top, to act on network packets entering an interface, timeouts expiring,
+mouse clicks, or other types of events.  Such applications are often
+very well suited to use an event loop.
+
+Applications that need to churn massively parallel algorithms are more
+suitable for running multiple (independent) threads on several CPU
+cores.  However, threaded applications must deal with the side effects
+of concurrency, like race conditions, deadlocks, live locks, etc.
+Writing error free threaded applications is hard, debugging them can be
+even harder.
+
+Sometimes the combination of multiple threads *and* an event loop per
+thread can be the best approach, but each application of course needs to
+be broken down individually to find the most optimal approach.  Do keep
+in mind, however, that not all systems your application will run on have
+multiple CPU cores -- some small embedded systems still use a single CPU
+core, even though they run Linux, with multiple threads a program may
+actually run slower!  Always profile your program, and if possible, test
+it on different architectures.
+
+[libuEv] is a simple event loop in the style of the more established
+[libevent][1], [libev][2] and the venerable [Xt(3)][3] event loop.  The
+*u* (micro) in the name refers to both the small feature set and the
+small size overhead impact of the library.  The primary target of
+[libuEv] is a modern Linux system.
+
+Experienced developers may appreciate that [libuEv] is built on top of
+modern Linux APIs: epoll, timerfd and signalfd.  Note, a certain amount
+of care is needed when dealing with APIs that employ signalfd.  For
+details, see [this article][4] at [lwn.net](http://lwn.net).
+
+> “Event driven software improves concurrency” -- [Dave Zarzycki, Apple]
+
+
+API
+---
+
+The C interface to [libuEv] is very simple.  It handles three different
+types of events: I/O (files, sockets, message queues, etc.), timers, and
+signals.  With a slight caveat on signals
+
+```C
+    /* Callback example, arg is passed from watcher's *_init()
+     * w->fd holds the file descriptor, events is set by libuEv
+     * to indicate if any of UEV_READ and/or UEV_WRITE is ready.
+     */
+    void callback       (uev_t *w, void *arg, int events);
+
+    /* Event loop functions, notice use of flags! */
+    int uev_init        (uev_ctx_t *ctx);
+    int uev_exit        (uev_ctx_t *ctx);
+    int uev_run         (uev_ctx_t *ctx, int flags);         /* UEV_NONE, UEV_ONCE, and/or UEV_NONBLOCK */
+    
+    /* I/O watcher:     fd is non-blocking, events is UEV_READ and/or UEV_WRITE */
+    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);
+    
+    /* Timer watcher:   timeout and period in milliseconds */
+    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); /* Change timeout or period */
+    int uev_timer_start (uev_t *w);                          /* Restart a stopped timer */
+    int uev_timer_stop  (uev_t *w);                          /* Stop a timer */
+    
+    /* Signal watcher:  signo is the signal to wait for, e.g., SIGTERM */
+    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);               /* Change signal to wait for */
+    int uev_signal_start(uev_t *w);                          /* Restart a stopped signal watcher */
+    int uev_signal_stop (uev_t *w);                          /* Stop signal watcher */
+```
+
+To monitor events the developer first creates an *event context*, this
+is achieved by calling `uev_init()` with a pointer to a (thread) local
+`uev_ctx_t` variable.
+
+```C
+    uev_ctx_t ctx;
+
+    uev_init(&ctx);
+```
+
+Then, for each event to be monitored, a *watcher* is registered with the
+event context.  The watcher, an `uev_t`, is initialized with the proper
+file descriptor to monitor, and an event callback function, by calling
+the event type's `_init()` function with the `uev_ctx_t` context.
+
+```C
+    void cleanup_exit(uev_t *w, void *arg, int events)
+    {
+        /* Graceful exit, with optional cleanup ... */
+        uev_exit(w->ctx);
+    }
+    
+    uev_t termw;
+
+    uev_signal_init(&ctx, &term, cleanup_exit, NULL, SIGTERM);
+```
+
+When all watchers are registered, call the *event loop* with `uev_run()`
+and the argument to the event context.  The `flags` parameter can be
+used to integrate [libuEv] into another event loop.  With `flags` set to
+`UEV_ONCE` the event loop returns after having served the first event.
+If `flags` is set to `UEV_ONCE | UEV_NONBLOCK` the event loop returns
+immediately if no event is available.
+
+```C
+    uev_run(&ctx, UEV_NONE);
+```
+
+In case of errors, stream close, or peer shutdown, libuEv handles much
+internally, but also lets the callback run.  This is useful for stateful
+connections to be able to detect EOF.
+
+Summary:
+
+1. Prepare an event context with `uev_init()`
+2. Register event callbacks with `uev_io_init()`, `uev_signal_init()`
+   or `uev_timer_init()`
+3. Enter the event loop with `uev_run()`
+4. Leave the event loop with `uev_exit()`, possibly from a callback
+
+**Note 1:** Make sure to use non-blocking stream I/O!  Most hard to find
+bugs in event driven applications are due to sockets and files being
+opened in blocking mode.  Be careful out there!
+
+**Note 2:** When closing a descriptor or socket, make sure to first stop
+  your watcher, if possible.  This will help prevent any nasty side
+  effects on your program.
+
+**Note 3:** As mentioned above, a certain amount of care is needed when
+dealing with signalfd.  This means that if your application, for
+instance, uses `system()` you must redesign that to use `fork()`, and
+then in the child, unblock all signals blocked by your parent process,
+before you run `exec()`.  This because Linux does not unblock signals
+for your children, and neither does most (all?) C-libraries.  An example
+of this, from [finit][6], implementing `run()` as a better replacement
+to `system()`, which sucks anyawy :)
+
+
+Example
+-------
+
+Here follows a very brief example to illustrate how one can use [libuEv]
+to act upon joystick input.
+
+```C
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "uev.h"
+
+struct js_event {
+	uint32_t time;		/* event timestamp in milliseconds */
+	int16_t  value;		/* value */
+	uint8_t  type;		/* event type */
+	uint8_t  number;	/* axis/button number */
+} e;
+
+static void joystick_cb(uev_t *w, void *arg, int events)
+{
+	read (w->fd, &e, sizeof(e));
+
+	switch (e.type) {
+	case 1:
+		if (e.value) printf("Button %d pressed\n", e.number);
+		else 	     printf("Button %d released\n", e.number);
+		break;
+
+	case 2:
+		printf("Joystick axis %d moved, value %d!\n", e.number, e.value);
+		break;
+	}
+}
+
+int main(void)
+{
+	int       fd = open("/dev/input/js1", O_RDONLY, O_NONBLOCK);
+	uev_t     js1_watcher;
+	uev_ctx_t ctx;
+
+	if (fd < 0)
+		errx(errno, "Cannot find a joystick attached.");
+
+	uev_init(&ctx);
+	uev_io_init(&ctx, &js1_watcher, joystick_cb, NULL, fd, UEV_READ);
+
+	puts("Starting, press Ctrl-C to exit.");
+
+	return uev_run(&ctx, 0);
+}
+```
+
+To compile the program, save the code as `joystick.c` and call GCC with
+`gcc -o joystick joystick.c io.c timer.c signal.c main.c` from this
+directory, skips using a Makefile altogether.  Alternatively, call the
+`Makefile` with <kbd>make joystick</kbd> from this directory.
+
+More complete and relevant example uses of [libuEv] is the TFTP/FTP
+server [uftpd][5], and the Linux `/sbin/init` replacement [finit][6].
+Both use [libuEv] as a GIT submodule.
+
+Also, see the `bench.c` program (<kbd>make bench</kbd> from within the
+library) for [reference benchmarks][7] against libevent and libev.
 
 
 Build & Install
 ---------------
 
-The library is built and developed for GNU/Linux systems, as such it may
-use GNU GCC and GNU Make specific features.  Patches to support *BSD
-kqueue are most welcome.
+The library is built for and developed on GNU/Linux systems, so it may
+use GCC and GNU Make specific extensions here and there.  This is not on
+purpose and patches to correct this are most welcome.  Particularly
+patches to support *BSD and its kqueue interface.
 
-   * `make all`: The library
-   * `make test`: Test and showcase
-   * `make install`: Honors $prefix and $DESTDIR environment variables
+* <kbd>make all</kbd>: The library
+* <kbd>make test</kbd>: Test and showcase
+* <kbd>make install</kbd>: Honors `$prefix` and `$DESTDIR` environment variables
+
+Size of [libuEv]:
+
+    $ make strip
+    CC      main.o
+    CC      io.o
+    CC      timer.o
+    CC      signal.o
+    ARCHIVE libuev.a
+    LINK    libuev.so.1
+    STRIP   libuev.a
+    STRIP   libuev.so.1
+    text	   data	    bss	    dec	    hex	filename
+    1177	      0	      0	   1177	    499	main.o     (ex libuev.a)
+     308	      0	      0	    308	    134	io.o       (ex libuev.a)
+     682	      0	      0	    682	    2aa	timer.o    (ex libuev.a)
+     563	      0	      0	    563	    233	signal.o   (ex libuev.a)
+    6306	    768	      8	   7082	   1baa	libuev.so.1
 
 
-Warning
--------
+Origin & References
+--------------------
 
-Please be advised, libuev is not thread safe!  It is primarily intended
-for use-cases where the engineer wants to avoid the use of threads.  To
-support threads the signal handling needs to be patched first, other
-than that an event context per thread should be sufficient.
+[libuEv] was originally based on [LibUEvent][8] by [Flemming Madsen] but
+has been completely rewritten with a much clearer API.  Now more similar
+to the famous [libev][2] by [Mark Lehmann].  Another small event library
+used for inspiration is the very small [Picoev][9] by [Oku Kazuho].
 
+[1]: http://libevent.org
+[2]: http://software.schmorp.de/pkg/libev.html
+[3]: http://unix.com/man-page/All/3x/XtDispatchEvent
+[4]: http://lwn.net/Articles/415684/
+[5]: https://github.com/troglobit/uftpd
+[6]: https://github.com/troglobit/finit
+[7]: http://libev.schmorp.de/bench.html
+[8]: http://code.google.com/p/libuevent/
+[9]: https://github.com/kazuho/picoev
+[Travis]:          https://travis-ci.org/troglobit/libuev
+[Travis Status]:   https://travis-ci.org/troglobit/libuev.png?branch=master
+[Coverity Scan]:   https://scan.coverity.com/projects/3846
+[Coverity Status]: https://scan.coverity.com/projects/3846/badge.svg
+[LibuEV]:          https://github.com/troglobit/libuev
+[Oku Kazuho]:      https://github.com/kazuho
+[Mark Lehmann]:    http://software.schmorp.de
+[Joachim Nilsson]: http://troglobit.com
+[Flemming Madsen]: http://www.madsensoft.dk
+[Dave Zarzycki, Apple]: http://www.youtube.com/watch?v=cD_s6Fjdri8
 
-History and References
-----------------------
-
-Libuev is a fork of the original LibUEvent by Flemming Madsen but has
-been completely rewritten and is now more similar to the famous libev by
-Mark Lehmann.  Another small event library used for inspiration is the
-very small Picoev by Oku Kazuho.
-
-   * http://code.google.com/p/libuevent/
-   * http://software.schmorp.de/pkg/libev.html
-   * http://libev.schmorp.de/bench.html
-   * http://libevent.org/
-   * http://developer.cybozu.co.jp/archives/kazuho/2009/08/picoev-a-tiny-e.html
-   * http://coderepos.org/share/browser/lang/c/picoev/
+[libuEv] is developed and maintained by [Joachim Nilsson]
 
+<!--
+  -- Local Variables:
+  --  mode: markdown
+  -- End:
+  -->

TODO

@@ -0,0 +1 @@
+TODO.md

TODO.md

@@ -0,0 +1,5 @@
+LibuEv TODO
+===========
+
+* Make port to *BSD kqueue API, http://en.wikipedia.org/wiki/Kqueue
+

bench.c

@@ -32,7 +32,7 @@
  *
  * Sun 04/08/2013 - Modified by Joachim Nilsson <troglobit@gmail.com>
  *
- *     Adaptations for libuev, no libev/libevent API wrappers available.
+ *     Adaptations for libuEv, no libev/libevent API wrappers available.
  *     Reindent to Linux coding style
  */
 
@@ -70,7 +70,7 @@ static int *pipes;
 static uev_t *evio;
 static uev_t *evto;
 
-static void read_cb(uev_ctx_t *UNUSED(ctx), uev_t *w, void *arg, int UNUSED(events))
+static void read_cb(uev_t *w, void *arg, int UNUSED(events))
 {
 	int idx, widx;
 	u_char ch;
@@ -96,7 +96,7 @@ static void read_cb(uev_ctx_t *UNUSED(ctx), uev_t *w, void *arg, int UNUSED(even
 	}
 }
 
-static void timer_cb(uev_ctx_t UNUSED(*ctx), uev_t UNUSED(*w), void UNUSED(*arg), int UNUSED(events))
+static void timer_cb(uev_t UNUSED(*w), void UNUSED(*arg), int UNUSED(events))
 {
 	/* nop */
 }
@@ -208,16 +208,17 @@ int main(int argc, char **argv)
 		if (timers)
 			uev_timer_init(&ctx, &evto[i], timer_cb, NULL, 0, 0);
 		args[i].index = i;
-		uev_io_init(&ctx, &evio[i], read_cb, &args[i], -1, UEV_READ);
 
 #ifdef USE_PIPES
-		if (pipe(cp) == -1) {
+		if (pipe2(cp, O_NONBLOCK) == -1) {
 #else
-		if (socketpair(AF_UNIX, SOCK_STREAM, 0, cp) == -1) {
+		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++)

examples/Makefile

@@ -0,0 +1,54 @@
+# libuEv examples
+#
+# 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.
+#
+.PHONY: all clean
+
+TARGET      = signal test joystick
+OBJS       := $(addsuffix .o, $(TARGET))
+SRCS       := $(OBJS:.o=.c)
+DEPS       := $(SRCS:.c=.d)
+CPPFLAGS   += -I../
+LDFLAGS    := -L../
+LDLIBS     := ../$(STATICLIB)
+
+# This magic trick looks like a comment, but works on BSD PMake
+#include <../rules.mk>
+include ../rules.mk
+
+all: $(TARGET)
+
+signal: signal.o
+
+test: test.o
+
+joystick: joystick.o
+
+clean:
+	-@$(RM) $(TARGET) *.o
+
+distclean: clean
+	-@$(RM) $(DEPS) $(JUNK)
+
+# Include automatically generated rules
+-include $(DEPS)

examples/joystick.c

@@ -0,0 +1,84 @@
+/* Simple example of how to use libuEv with Linux joystick API
+ *
+ * Copyright (c) 2014-2015  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.
+ */
+
+#include <err.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "uev.h"
+
+#define UNUSED(arg) arg __attribute__ ((unused))
+
+struct js_event {
+	uint32_t time;		/* event timestamp in milliseconds */
+	int16_t  value;		/* value */
+	uint8_t  type;		/* event type */
+	uint8_t  number;	/* axis/button number */
+} e;
+
+static void joystick_cb(uev_t *w, void *UNUSED(arg), int UNUSED(events))
+{
+	if (read (w->fd, &e, sizeof(e)) < 0)
+		errx(errno, "Failed reading joystick event");
+
+	switch (e.type) {
+	case 1:
+		if (e.value) printf("Button %d pressed\n", e.number);
+		else 	     printf("Button %d released\n", e.number);
+		break;
+
+	case 2:
+		printf("Joystick axis %d moved, value %d!\n", e.number, e.value);
+		break;
+	}
+}
+
+int main(void)
+{
+	int       fd = open("/dev/input/js1", O_RDONLY, O_NONBLOCK);
+	uev_t     js1_watcher;
+	uev_ctx_t ctx;
+
+	if (fd < 0)
+		errx(errno, "Cannot find a joystick attached.");
+
+	uev_init(&ctx);
+	uev_io_init(&ctx, &js1_watcher, joystick_cb, NULL, fd, UEV_READ);
+
+	puts("Starting, press Ctrl-C to exit.");
+
+	return uev_run(&ctx, 0);
+}
+
+/**
+ * Local Variables:
+ *  compile-command: "gcc -o joystick joystick.c io.o timer.o signal.o main.o"
+ *  version-control: t
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

examples/signal.c

@@ -0,0 +1,142 @@
+/* Multiple signals, segfault and fork() to test sub-processes.
+ *
+ * Copyright (c) 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.
+ */
+
+#define _GNU_SOURCE
+#include <err.h>
+#include <sched.h>
+#include <signal.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/user.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "uev.h"
+
+#define UNUSED(arg) arg __attribute__ ((unused))
+#define DO_SEGFAULT 1
+
+typedef struct {
+	int magic;
+	void *ptr;
+} arg_t;
+
+/* Stack is not shared between parent and child, only the heap. */
+static arg_t arg = {
+	.magic = 1337,
+	.ptr = NULL
+};
+
+static int callback(arg_t *arg, int event, void *foo)
+{
+	arg_t *event_arg  = (arg_t *)foo;
+
+	printf("child: got magic %d and ptr %p, with event %d and event arg %p\n",
+	       arg->magic, arg->ptr, event, event_arg);
+
+	arg->magic = 7331;
+	arg->ptr   = &event_arg;
+
+	/* Cause segfault! */
+#if DO_SEGFAULT == 1
+	event_arg->ptr = arg->ptr;
+	printf("child: segfaulting failed!\n");
+#endif
+
+        return 42;
+}
+
+static void sigsegv_cb(uev_t *UNUSED(w), void *UNUSED(arg), int UNUSED(events))
+{
+	warnx("PID %d caused segfault.", getpid());
+	exit(-1);
+}
+
+static void sigchld_cb(uev_t *UNUSED(w), void *UNUSED(arg), int UNUSED(events))
+{
+        pid_t pid = waitpid(-1, NULL, WNOHANG);
+
+        if (-1 != pid)
+                warnx("PID %d exited, bye.", pid);
+}
+
+static void work_cb(uev_t *UNUSED(w), void *arg, int UNUSED(events))
+{
+	int    status = 0;
+        pid_t  pid;
+
+        pid = fork();
+        if (-1 == pid)
+                err(1, "fork");
+	if (!pid) {
+		status = callback(arg, 6137, NULL);
+                exit(status);
+        }
+
+        if (waitpid(pid, &status, 0) == -1)
+                err(1, "waitpid");
+
+	if (WIFEXITED(status))
+		printf("Child exited normally => %d\n", WEXITSTATUS(status));
+	else if (WCOREDUMP(status))
+		printf("Child crashed! %s\n", DO_SEGFAULT
+		       ? "As expected, everything is OK."
+		       : "This should not happen!");
+	else
+		printf("Child did not exit normally!\n");
+}
+
+static void exit_cb(uev_t *w, void *UNUSED(arg), int UNUSED(events))
+{
+        printf("Process deadline reached, exiting!\n");
+	uev_exit(w->ctx);
+}
+
+int main(void)
+{
+	uev_t sigsegv_watcher, sigchld_watcher, timeout_watcher, deadline_watcher;
+	uev_ctx_t ctx;
+
+	/* Initialize libuEv */
+	uev_init(&ctx);
+
+	/* Setup callbacks */
+	uev_signal_init(&ctx, &sigsegv_watcher, sigsegv_cb, NULL, SIGSEGV);
+	uev_signal_init(&ctx, &sigchld_watcher, sigchld_cb, NULL, SIGCHLD);
+	uev_timer_init(&ctx, &timeout_watcher, work_cb, &arg, 400, 0);
+	uev_timer_init(&ctx, &deadline_watcher, exit_cb, NULL, 1000, 0);
+
+	/* Start event loop */
+	return uev_run(&ctx, 0);
+}
+
+/**
+ * Local Variables:
+ *  version-control: t
+ *  indent-tabs-mode: t
+ *  c-file-style: "linux"
+ * End:
+ */

examples/test.c

@@ -1,7 +1,7 @@
-/* Test libuev event library
+/* Test libuEv event library
  *
- * Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
- * Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+ * 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
@@ -40,33 +40,33 @@ static int in, out;
 static int period = 0;
 static uev_t *watchdog;
 
-static void lifetime_cb(uev_ctx_t *ctx, uev_t UNUSED(*w), void *arg, int UNUSED(events))
+static void lifetime_cb(uev_t *w, void *arg, int UNUSED(events))
 {
-	fprintf(stderr, "\nLifetime exceeded %p\n", arg);
-	uev_exit(ctx);
+	fprintf(stderr, "\nLifetime exceeded, program completed successfully! (arg:%p)\n", arg);
+	uev_exit(w->ctx);
 }
 
 /* The pipe watchdog, if it triggers we haven't received data in time. */
-static void timeout_cb(uev_ctx_t *ctx, uev_t *w, void *arg, int UNUSED(events))
+static void timeout_cb(uev_t *w, void *arg, int UNUSED(events))
 {
 	watchdog = NULL;
 	fprintf(stderr, "\nTimeout exceeded %p\n", arg);
 
-	uev_timer_stop(w);
-	uev_exit(ctx);
+	// uev_timer_stop(w); <-- No need to stop timers with period=0 :)
+	uev_exit(w->ctx);
 }
 
-static void periodic_task(uev_ctx_t UNUSED(*ctx), uev_t UNUSED(*w), void UNUSED(*arg), int UNUSED(events))
+static void periodic_task(uev_t UNUSED(*w), void UNUSED(*arg), int UNUSED(events))
 {
 	fprintf(stderr, "|");
 }
 
-static void signal_cb(uev_ctx_t *UNUSED(ctx), uev_t *w, void *UNUSED(arg), int UNUSED(events))
+static void signal_cb(uev_t *w, void *UNUSED(arg), int UNUSED(events))
 {
 	fprintf(stderr, w->signo == SIGINT ? "^Cv" : "^\v");
 }
 
-static void pipe_read_cb(uev_ctx_t *UNUSED(ctx), uev_t UNUSED(*w), void UNUSED(*arg), int UNUSED(events))
+static void pipe_read_cb(uev_t UNUSED(*w), void UNUSED(*arg), int UNUSED(events))
 {
 	int cnt;
 	char msg[50];
@@ -80,7 +80,7 @@ static void pipe_read_cb(uev_ctx_t *UNUSED(ctx), uev_t UNUSED(*w), void UNUSED(*
 	fprintf(stderr, "%.*s.%d ", cnt, msg, cnt);
 }
 
-static void pipe_write_cb(uev_ctx_t UNUSED(*ctx), uev_t *w, void *arg, int UNUSED(events))
+static void pipe_write_cb(uev_t *w, void *arg, int UNUSED(events))
 {
 	my_t *my  = arg;
 	char *msg = "TESTING";
@@ -111,7 +111,7 @@ int main(void)
 	if (pipe(fd) < 0)
 		return 1;
 
-	/*  */
+	/* Initialize libuEv */
 	uev_init(&ctx);
 
 	/* Signal watchers, Ctrl-C => SIGINT, Ctrl-\ => SIGQUIT */
@@ -141,7 +141,7 @@ int main(void)
 	fprintf(stderr, "Period is %d must be 10: %s\n", period, 10 == period ? "OK" : "ERROR!");
 	if (10 != period)
 		return 1;
-                
+
 	return 0;
 }
 

io.c

@@ -1,7 +1,7 @@
-/* libuev - Micro event loop library
+/* libuEv - Micro event loop library
  *
- * Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
- * Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+ * 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
@@ -23,12 +23,14 @@
  * 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 ctx     A valid libuEv context
  * @param w       Pointer to an uev_t watcher
  * @param cb      I/O callback
  * @param arg     Optional callback argument
@@ -39,12 +41,14 @@
  */
 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;
 
-	if (fd < 0)
-		return 0;
-
 	return uev_watcher_start(w);
 }
 
@@ -58,18 +62,26 @@ int uev_io_init(uev_ctx_t *ctx, uev_t *w, uev_cb_t *cb, void *arg, int fd, int e
  */
 int uev_io_set(uev_t *w, int fd, int events)
 {
-	if (uev_io_stop(w))
-		return -1;
-
-	/* Remove from internal list */
-	LIST_REMOVE(w, link);
+	/* 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  Pointer to an uev_t watcher
+ * @param w  Watcher to stop
  *
  * @return POSIX OK(0) or non-zero with @param errno set on error.
  */

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_ */

rules.mk

@@ -0,0 +1,9 @@
+# Pretty printing and GCC -M for auto dep files
+%.o: %.c
+	@printf "  CC      $(subst $(ROOTDIR)/,,$(shell pwd)/)$@\n"
+	@$(CC) $(CFLAGS) $(CPPFLAGS) -c -MMD -MP -o $@ $<
+
+%: %.o
+	@printf "  LINK    $(subst $(ROOTDIR)/,,$(shell pwd)/)$@\n"
+	@$(CC) $(CFLAGS) $(LDFLAGS) -Wl,-Map,$@.map -o $@ $^ $(LDLIBS$(LDLIBS-$(@)))
+

signal.c

@@ -1,7 +1,7 @@
-/* libuev - Micro event loop library
+/* libuEv - Micro event loop library
  *
- * Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
- * Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+ * 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
@@ -33,7 +33,7 @@
 
 /**
  * Create a signal watcher
- * @param ctx    A valid libuev context
+ * @param ctx    A valid libuEv context
  * @param w      Pointer to an uev_t watcher
  * @param cb     Timer callback
  * @param arg    Optional callback argument
@@ -46,6 +46,12 @@ 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);
 	if (fd < 0)
@@ -81,6 +87,9 @@ int uev_signal_set(uev_t *w, int signo)
 		return -1;
 	}
 
+	/* Remember for callbacks and start/stop */
+	w->signo = signo;
+
 	/* Handle stopped signal watchers */
 	if (w->fd < 0) {
 		/* Remove from internal list */
@@ -104,6 +113,26 @@ int uev_signal_set(uev_t *w, int signo)
 	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

timer.c

@@ -1,7 +1,7 @@
-/* libuev - Micro event loop library
+/* libuEv - Micro event loop library
  *
- * Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
- * Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+ * 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
@@ -43,7 +43,7 @@ static void msec2tspec(int msec, struct timespec *ts)
 
 /**
  * Create and start a timer watcher
- * @param ctx      A valid libuev context
+ * @param ctx      A valid libuEv context
  * @param w        Pointer to an uev_t watcher
  * @param cb       Callback function
  * @param arg      Optional callback argument
@@ -123,11 +123,28 @@ int uev_timer_set(uev_t *w, int timeout, int period)
 		msec2tspec(timeout, &time.it_value);
 		msec2tspec(period, &time.it_interval);
 		timerfd_settime(w->fd, 0, &time, NULL);
-
-		return uev_watcher_start(w);
 	}
 
-	return 0;
+	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->timeout, w->period);
 }
 
 /**

uev.c

@@ -1,7 +1,7 @@
-/* libuev - Micro event loop library
+/* libuEv - Micro event loop library
  *
- * Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
- * Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+ * 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
@@ -24,6 +24,7 @@
  */
 
 #include <errno.h>
+#include <fcntl.h>		/* O_CLOEXEC */
 #include <string.h>		/* memset() */
 #include <sys/epoll.h>
 #include <sys/signalfd.h>	/* struct signalfd_siginfo */
@@ -33,7 +34,29 @@
 
 #define UNUSED(arg) arg __attribute__ ((unused))
 
-/* Private to libuev, do not use directly! */
+
+static int _init(uev_ctx_t *ctx, int close_old)
+{
+	int fd = epoll_create1(O_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) {
@@ -41,20 +64,18 @@ int uev_watcher_init(uev_ctx_t *ctx, uev_t *w, uev_type_t type, uev_cb_t *cb, vo
 		return -1;
 	}
 
-	memset(w, 0, sizeof(*w));
 	w->ctx    = ctx;
-	w->fd     = fd;
 	w->type   = type;
+	w->active = 0;
+	w->fd     = fd;
 	w->cb     = (void *)cb;
 	w->arg    = arg;
 	w->events = events;
 
-	LIST_INSERT_HEAD(&w->ctx->watchers, w, link);
-
 	return 0;
 }
 
-/* Private to libuev, do not use directly! */
+/* Private to libuEv, do not use directly! */
 int uev_watcher_start(uev_t *w)
 {
 	struct epoll_event ev;
@@ -67,17 +88,20 @@ int uev_watcher_start(uev_t *w)
 	if (w->active)
 		return 0;
 
-	ev.events   = w->events;
+	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! */
+/* Private to libuEv, do not use directly! */
 int uev_watcher_stop(uev_t *w)
 {
 	if (!w) {
@@ -88,10 +112,15 @@ int uev_watcher_stop(uev_t *w)
 	if (!w->active)
 		return 0;
 
-	/* Remove from kernel */
-	epoll_ctl(w->ctx->fd, EPOLL_CTL_DEL, w->fd, NULL);
 	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;
 }
 
@@ -103,22 +132,20 @@ int uev_watcher_stop(uev_t *w)
  */
 int uev_init(uev_ctx_t *ctx)
 {
-	int fd;
-
-	fd = epoll_create(1);
-	if (fd < 0)
+	if (!ctx) {
+		errno = EINVAL;
 		return -1;
+	}
 
 	memset(ctx, 0, sizeof(*ctx));
-	ctx->fd = fd;
 	LIST_INIT(&ctx->watchers);
 
-	return 0;
+	return _init(ctx, 0);
 }
 
 /**
  * Terminate the event loop
- * @param ctx  A valid libuev context
+ * @param ctx  A valid libuEv context
  *
  * @return POSIX OK(0) or non-zero with @param errno set on error.
  */
@@ -162,10 +189,17 @@ int uev_exit(uev_ctx_t *ctx)
 
 /**
  * Start the event loop
- * @param ctx    A valid libuev context
+ * @param ctx    A valid libuEv context
  * @param flags  A mask of %UEV_ONCE and %UEV_NONBLOCK, or zero
  *
- * @return POSIX OK(0) upon successful termination of the event loop, or non-zero on error.
+ * 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)
 {
@@ -199,20 +233,54 @@ int uev_run(uev_ctx_t *ctx, int flags)
 
 			if (EINTR == errno)
 				continue; /* Signalled, try again */
-		exit:
-			result = -1;
-			ctx->running = 0;
-			break;
+
+			/* 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_TIMER_TYPE == w->type) {
 				uint64_t exp;
 
-				if (read(w->fd, &exp, sizeof(exp)) != sizeof(exp))
-					goto exit;
+				if (read(w->fd, &exp, sizeof(exp)) != sizeof(exp)) {
+					uev_exit(ctx);
+					return -3;
+				}
 
 				if (!w->period)
 					w->timeout = 0;
@@ -222,14 +290,14 @@ int uev_run(uev_ctx_t *ctx, int flags)
 				struct signalfd_siginfo fdsi;
 				ssize_t sz = sizeof(fdsi);
 
-				if (read(w->fd, &fdsi, sz) != sz)
-					goto exit;
-
-				w->signo = fdsi.ssi_signo;
+				if (read(w->fd, &fdsi, sz) != sz) {
+					uev_exit(ctx);
+					return -4;
+				}
 			}
 
 			if (w->cb)
-				w->cb((struct uev *)ctx, w, w->arg);
+				w->cb(w, w->arg, events[i].events & UEV_EVENT_MASK);
 
 			if (UEV_TIMER_TYPE == w->type) {
 				if (!w->timeout)

uev.h

@@ -1,7 +1,7 @@
-/* libuev - Micro event loop library
+/* libuEv - Micro event loop library
  *
- * Copyright (c) 2012  Flemming Madsen <flemming!madsen()madsensoft!dk>
- * Copyright (c) 2013  Joachim Nilsson <troglobit()gmail!com>
+ * 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
@@ -28,7 +28,8 @@
 
 #include <stdio.h>
 #include <sys/epoll.h>
-#include <sys/queue.h>
+
+#include "queue.h"	       /* OpenBSD queue.h > old GLIBC version */
 
 /* Max. number of simulateneous events */
 #define UEV_MAX_EVENTS  10
@@ -37,6 +38,7 @@
 #define UEV_NONE        0
 #define UEV_READ        EPOLLIN
 #define UEV_WRITE       EPOLLOUT
+#define UEV_EVENT_MASK  (UEV_READ | UEV_WRITE)
 
 /* Run flags */
 #define UEV_ONCE        1
@@ -52,10 +54,11 @@ typedef enum {
 /* Forward declare due to dependencys, don't try this at home kids. */
 struct uev;
 
-/* Main libuev context type */
+/* Main libuEv context type */
 typedef struct {
 	int             running;
 	int             fd;	/* For epoll() */
+	uint32_t        errors;
 	LIST_HEAD(,uev) watchers;
 } uev_ctx_t;
 
@@ -71,7 +74,7 @@ typedef struct uev {
 	int             events;
 
 	/* Watcher callback with optional argument */
-	void          (*cb)(struct uev *, struct uev *, void *);
+	void          (*cb)(struct uev *, void *, int);
 	void           *arg;
 
 	/* Timer watchers, time in milliseconds */
@@ -83,7 +86,7 @@ typedef struct uev {
 } uev_t;
 
 /* Generic callback for watchers */
-typedef void (uev_cb_t)(uev_ctx_t *ctx, uev_t *w, void *arg, int events);
+typedef void (uev_cb_t)(uev_t *w, void *arg, int events);
 
 /* Private methods, 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);
@@ -97,14 +100,17 @@ 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_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_ */