ext/em.cpp
/*****************************************************************************
$Id$
File: em.cpp
Date: 06Apr06
Copyright (C) 2006-07 by Francis Cianfrocca. All Rights Reserved.
Gmail: blackhedd
This program is free software; you can redistribute it and/or modify
it under the terms of either: 1) the GNU General Public License
as published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version; or 2) Ruby's License.
See the file COPYING for complete licensing information.
*****************************************************************************/
// THIS ENTIRE FILE WILL EVENTUALLY BE FOR UNIX BUILDS ONLY.
//#ifdef OS_UNIX
#include "project.h"
/* The numer of max outstanding timers was once a const enum defined in em.h.
* Now we define it here so that users can change its value if necessary.
*/
static unsigned int MaxOutstandingTimers = 100000;
/* The number of accept() done at once in a single tick when the acceptor
* socket becomes readable.
*/
static unsigned int SimultaneousAcceptCount = 10;
/* Internal helper to create a socket with SOCK_CLOEXEC set, and fall
* back to fcntl'ing it if the headers/runtime don't support it.
*/
SOCKET EmSocket (int domain, int type, int protocol)
{
SOCKET sd;
#ifdef HAVE_SOCKET_CLOEXEC
sd = socket (domain, type | SOCK_CLOEXEC, protocol);
if (sd == INVALID_SOCKET) {
sd = socket (domain, type, protocol);
if (sd < 0) {
return sd;
}
SetFdCloexec(sd);
}
#else
sd = socket (domain, type, protocol);
if (sd == INVALID_SOCKET) {
return sd;
}
SetFdCloexec(sd);
#endif
return sd;
}
/***************************************
STATIC EventMachine_t::GetMaxTimerCount
***************************************/
int EventMachine_t::GetMaxTimerCount()
{
return MaxOutstandingTimers;
}
/***************************************
STATIC EventMachine_t::SetMaxTimerCount
***************************************/
void EventMachine_t::SetMaxTimerCount (int count)
{
/* Allow a user to increase the maximum number of outstanding timers.
* If this gets "too high" (a metric that is of course platform dependent),
* bad things will happen like performance problems and possible overuse
* of memory.
* The actual timer mechanism is very efficient so it's hard to know what
* the practical max, but 100,000 shouldn't be too problematical.
*/
if (count < 100)
count = 100;
MaxOutstandingTimers = count;
}
int EventMachine_t::GetSimultaneousAcceptCount()
{
return SimultaneousAcceptCount;
}
void EventMachine_t::SetSimultaneousAcceptCount (int count)
{
if (count < 1)
count = 1;
SimultaneousAcceptCount = count;
}
/******************************
EventMachine_t::EventMachine_t
******************************/
EventMachine_t::EventMachine_t (EMCallback event_callback, Poller_t poller):
NumCloseScheduled (0),
HeartbeatInterval(2000000),
EventCallback (event_callback),
LoopBreakerReader (INVALID_SOCKET),
LoopBreakerWriter (INVALID_SOCKET),
bTerminateSignalReceived (false),
Poller (poller),
epfd (-1),
kqfd (-1)
#ifdef HAVE_INOTIFY
, inotify (NULL)
#endif
{
// Default time-slice is just smaller than one hundred mills.
Quantum.tv_sec = 0;
Quantum.tv_usec = 90000;
// Override the requested poller back to default if needed.
#if !defined(HAVE_EPOLL) && !defined(HAVE_KQUEUE)
Poller = Poller_Default;
#endif
/* Initialize monotonic timekeeping on OS X before the first call to GetRealTime */
#ifdef OS_DARWIN
(void) mach_timebase_info(&mach_timebase);
#endif
#ifdef OS_WIN32
TickCountTickover = 0;
LastTickCount = 0;
#endif
// Make sure the current loop time is sane, in case we do any initializations of
// objects before we start running.
_UpdateTime();
/* We initialize the network library here (only on Windows of course)
* and initialize "loop breakers." Our destructor also does some network-level
* cleanup. There's thus an implicit assumption that any given instance of EventMachine_t
* will only call ::Run once. Is that a good assumption? Should we move some of these
* inits and de-inits into ::Run?
*/
#ifdef OS_WIN32
WSADATA w;
WSAStartup (MAKEWORD (1, 1), &w);
#endif
_InitializeLoopBreaker();
SelectData = new SelectData_t();
}
/*******************************
EventMachine_t::~EventMachine_t
*******************************/
EventMachine_t::~EventMachine_t()
{
// Run down descriptors
size_t i;
for (i = 0; i < NewDescriptors.size(); i++)
delete NewDescriptors[i];
for (i = 0; i < Descriptors.size(); i++)
delete Descriptors[i];
close (LoopBreakerReader);
close (LoopBreakerWriter);
// Remove any file watch descriptors
while(!Files.empty()) {
std::map<int, Bindable_t*>::iterator f = Files.begin();
UnwatchFile (f->first);
}
if (epfd != -1)
close (epfd);
if (kqfd != -1)
close (kqfd);
delete SelectData;
}
/****************************
EventMachine_t::ScheduleHalt
****************************/
void EventMachine_t::ScheduleHalt()
{
/* This is how we stop the machine.
* This can be called by clients. Signal handlers will probably
* set the global flag.
* For now this means there can only be one EventMachine ever running at a time.
*
* IMPORTANT: keep this light, fast, and async-safe. Don't do anything frisky in here,
* because it may be called from signal handlers invoked from code that we don't
* control. At this writing (20Sep06), EM does NOT install any signal handlers of
* its own.
*
* We need a FAQ. And one of the questions is: how do I stop EM when Ctrl-C happens?
* The answer is to call evma_stop_machine, which calls here, from a SIGINT handler.
*/
bTerminateSignalReceived = true;
/* Signal the loopbreaker so we break out of long-running select/epoll/kqueue and
* notice the halt boolean is set. Signalling the loopbreaker also uses a single
* signal-safe syscall.
*/
SignalLoopBreaker();
}
bool EventMachine_t::Stopping()
{
return bTerminateSignalReceived;
}
/*******************************
EventMachine_t::GetTimerQuantum
*******************************/
uint64_t EventMachine_t::GetTimerQuantum()
{
/* Convert timer-quantum to microseconds */
return (Quantum.tv_sec * 1000 + (Quantum.tv_usec + 500) / 1000) * 1000;
}
/*******************************
EventMachine_t::SetTimerQuantum
*******************************/
void EventMachine_t::SetTimerQuantum (int interval)
{
/* We get a timer-quantum expressed in milliseconds.
*/
if ((interval < 5) || (interval > 5*60*1000))
throw std::runtime_error ("invalid timer-quantum");
Quantum.tv_sec = interval / 1000;
Quantum.tv_usec = (interval % 1000) * 1000;
}
/*************************************
(STATIC) EventMachine_t::SetuidString
*************************************/
#ifdef OS_UNIX
void EventMachine_t::SetuidString (const char *username)
{
/* This method takes a caller-supplied username and tries to setuid
* to that user. There is no meaningful implementation (and no error)
* on Windows. On Unix, a failure to setuid the caller-supplied string
* causes a fatal abort, because presumably the program is calling here
* in order to fulfill a security requirement. If we fail silently,
* the user may continue to run with too much privilege.
*
* TODO, we need to decide on and document a way of generating C++ level errors
* that can be wrapped in documented Ruby exceptions, so users can catch
* and handle them. And distinguish it from errors that we WON'T let the Ruby
* user catch (like security-violations and resource-overallocation).
* A setuid failure here would be in the latter category.
*/
if (!username || !*username)
throw std::runtime_error ("setuid_string failed: no username specified");
errno = 0;
struct passwd *p = getpwnam (username);
if (!p) {
if (errno) {
char buf[200];
snprintf (buf, sizeof(buf)-1, "setuid_string failed: %s", strerror(errno));
throw std::runtime_error (buf);
} else {
throw std::runtime_error ("setuid_string failed: unknown username");
}
}
if (setuid (p->pw_uid) != 0)
throw std::runtime_error ("setuid_string failed: no setuid");
// Success.
}
#else
void EventMachine_t::SetuidString (const char *username UNUSED) { }
#endif
/****************************************
(STATIC) EventMachine_t::SetRlimitNofile
****************************************/
#ifdef OS_UNIX
int EventMachine_t::SetRlimitNofile (int nofiles)
{
struct rlimit rlim;
getrlimit (RLIMIT_NOFILE, &rlim);
if (nofiles >= 0) {
rlim.rlim_cur = nofiles;
if ((unsigned int)nofiles > rlim.rlim_max)
rlim.rlim_max = nofiles;
setrlimit (RLIMIT_NOFILE, &rlim);
// ignore the error return, for now at least.
// TODO, emit an error message someday when we have proper debug levels.
}
getrlimit (RLIMIT_NOFILE, &rlim);
return rlim.rlim_cur;
}
#else
int EventMachine_t::SetRlimitNofile (int nofiles UNUSED) { return 0; }
#endif
/*********************************
EventMachine_t::SignalLoopBreaker
*********************************/
void EventMachine_t::SignalLoopBreaker()
{
#ifdef OS_UNIX
(void)write (LoopBreakerWriter, "", 1);
#endif
#ifdef OS_WIN32
sendto (LoopBreakerReader, "", 0, 0, (struct sockaddr*)&(LoopBreakerTarget), sizeof(LoopBreakerTarget));
#endif
}
/**************************************
EventMachine_t::_InitializeLoopBreaker
**************************************/
void EventMachine_t::_InitializeLoopBreaker()
{
/* A "loop-breaker" is a socket-descriptor that we can write to in order
* to break the main select loop. Primarily useful for things running on
* threads other than the main EM thread, so they can trigger processing
* of events that arise exogenously to the EM.
* Keep the loop-breaker pipe out of the main descriptor set, otherwise
* its events will get passed on to user code.
*/
#ifdef OS_UNIX
int fd[2];
#if defined (HAVE_CLOEXEC) && defined (HAVE_PIPE2)
int pipestatus = pipe2(fd, O_CLOEXEC);
if (pipestatus < 0) {
if (pipe(fd))
throw std::runtime_error (strerror(errno));
}
#else
if (pipe (fd))
throw std::runtime_error (strerror(errno));
#endif
if (!SetFdCloexec(fd[0]) || !SetFdCloexec(fd[1]))
throw std::runtime_error (strerror(errno));
LoopBreakerWriter = fd[1];
LoopBreakerReader = fd[0];
/* 16Jan11: Make sure the pipe is non-blocking, so more than 65k loopbreaks
* in one tick do not fill up the pipe and block the process on write() */
SetSocketNonblocking (LoopBreakerWriter);
#endif
#ifdef OS_WIN32
SOCKET sd = EmSocket (AF_INET, SOCK_DGRAM, 0);
if (sd == INVALID_SOCKET)
throw std::runtime_error ("no loop breaker socket");
SetSocketNonblocking (sd);
memset (&LoopBreakerTarget, 0, sizeof(LoopBreakerTarget));
LoopBreakerTarget.sin_family = AF_INET;
LoopBreakerTarget.sin_addr.s_addr = inet_addr ("127.0.0.1");
srand ((int)time(NULL));
int i;
for (i=0; i < 100; i++) {
int r = (rand() % 10000) + 20000;
LoopBreakerTarget.sin_port = htons (r);
if (bind (sd, (struct sockaddr*)&LoopBreakerTarget, sizeof(LoopBreakerTarget)) == 0)
break;
}
if (i == 100)
throw std::runtime_error ("no loop breaker");
LoopBreakerReader = sd;
#endif
#ifdef HAVE_EPOLL
if (Poller == Poller_Epoll) {
epfd = epoll_create1(EPOLL_CLOEXEC);
if (epfd == -1) {
char buf[200];
snprintf (buf, sizeof(buf)-1, "unable to create epoll descriptor: %s", strerror(errno));
throw std::runtime_error (buf);
}
assert (LoopBreakerReader >= 0);
LoopbreakDescriptor *ld = new LoopbreakDescriptor (LoopBreakerReader, this);
assert (ld);
Add (ld);
}
#endif
#ifdef HAVE_KQUEUE
if (Poller == Poller_Kqueue) {
kqfd = kqueue();
if (kqfd == -1) {
char buf[200];
snprintf (buf, sizeof(buf)-1, "unable to create kqueue descriptor: %s", strerror(errno));
throw std::runtime_error (buf);
}
// cloexec not needed. By definition, kqueues are not carried across forks.
assert (LoopBreakerReader >= 0);
LoopbreakDescriptor *ld = new LoopbreakDescriptor (LoopBreakerReader, this);
assert (ld);
Add (ld);
}
#endif
}
/***************************
EventMachine_t::_UpdateTime
***************************/
void EventMachine_t::_UpdateTime()
{
MyCurrentLoopTime = GetRealTime();
}
/***************************
EventMachine_t::GetRealTime
***************************/
// Two great writeups of cross-platform monotonic time are at:
// http://www.python.org/dev/peps/pep-0418
// http://nadeausoftware.com/articles/2012/04/c_c_tip_how_measure_elapsed_real_time_benchmarking
// Uncomment the #pragma messages to confirm which compile-time option was used
uint64_t EventMachine_t::GetRealTime()
{
uint64_t current_time;
#if defined(HAVE_CONST_CLOCK_MONOTONIC_RAW)
// #pragma message "GetRealTime: clock_gettime CLOCK_MONOTONIC_RAW"
// Linux 2.6.28 and above
struct timespec tv;
clock_gettime (CLOCK_MONOTONIC_RAW, &tv);
current_time = (((uint64_t)(tv.tv_sec)) * 1000000LL) + ((uint64_t)((tv.tv_nsec)/1000));
#elif defined(HAVE_CONST_CLOCK_MONOTONIC)
// #pragma message "GetRealTime: clock_gettime CLOCK_MONOTONIC"
// Linux, FreeBSD 5.0 and above, Solaris 8 and above, OpenBSD, NetBSD, DragonflyBSD
struct timespec tv;
clock_gettime (CLOCK_MONOTONIC, &tv);
current_time = (((uint64_t)(tv.tv_sec)) * 1000000LL) + ((uint64_t)((tv.tv_nsec)/1000));
#elif defined(HAVE_GETHRTIME)
// #pragma message "GetRealTime: gethrtime"
// Solaris and HP-UX
current_time = (uint64_t)gethrtime() / 1000;
#elif defined(OS_DARWIN)
// #pragma message "GetRealTime: mach_absolute_time"
// Mac OS X
// https://developer.apple.com/library/mac/qa/qa1398/_index.html
current_time = mach_absolute_time() * mach_timebase.numer / mach_timebase.denom / 1000;
#elif defined(OS_UNIX)
// #pragma message "GetRealTime: gettimeofday"
// Unix fallback
struct timeval tv;
gettimeofday (&tv, NULL);
current_time = (((uint64_t)(tv.tv_sec)) * 1000000LL) + ((uint64_t)(tv.tv_usec));
#elif defined(OS_WIN32)
// #pragma message "GetRealTime: GetTickCount"
// Future improvement: use GetTickCount64 in Windows Vista / Server 2008
unsigned tick = GetTickCount();
if (tick < LastTickCount)
TickCountTickover += 1;
LastTickCount = tick;
current_time = ((uint64_t)TickCountTickover << 32) + (uint64_t)tick;
current_time *= 1000; // convert to microseconds
#else
// #pragma message "GetRealTime: time"
// Universal fallback
current_time = (uint64_t)time(NULL) * 1000000LL;
#endif
return current_time;
}
/***********************************
EventMachine_t::_DispatchHeartbeats
***********************************/
void EventMachine_t::_DispatchHeartbeats()
{
// Store the first processed heartbeat descriptor and bail out if
// we see it again. This fixes an infinite loop in case the system time
// is changed out from underneath MyCurrentLoopTime.
const EventableDescriptor *head = NULL;
while (true) {
std::multimap<uint64_t,EventableDescriptor*>::iterator i = Heartbeats.begin();
if (i == Heartbeats.end())
break;
if (i->first > MyCurrentLoopTime)
break;
EventableDescriptor *ed = i->second;
if (ed == head)
break;
ed->Heartbeat();
QueueHeartbeat(ed);
if (head == NULL)
head = ed;
}
}
/******************************
EventMachine_t::QueueHeartbeat
******************************/
void EventMachine_t::QueueHeartbeat(EventableDescriptor *ed)
{
uint64_t heartbeat = ed->GetNextHeartbeat();
if (heartbeat) {
#ifndef HAVE_MAKE_PAIR
Heartbeats.insert (std::multimap<uint64_t,EventableDescriptor*>::value_type (heartbeat, ed));
#else
Heartbeats.insert (std::make_pair (heartbeat, ed));
#endif
}
}
/******************************
EventMachine_t::ClearHeartbeat
******************************/
void EventMachine_t::ClearHeartbeat(uint64_t key, EventableDescriptor* ed)
{
std::multimap<uint64_t,EventableDescriptor*>::iterator it;
std::pair<std::multimap<uint64_t,EventableDescriptor*>::iterator,std::multimap<uint64_t,EventableDescriptor*>::iterator> ret;
ret = Heartbeats.equal_range (key);
for (it = ret.first; it != ret.second; ++it) {
if (it->second == ed) {
Heartbeats.erase (it);
break;
}
}
}
/*******************
EventMachine_t::Run
*******************/
void EventMachine_t::Run()
{
while (RunOnce()) ;
}
/***********************
EventMachine_t::RunOnce
***********************/
bool EventMachine_t::RunOnce()
{
_UpdateTime();
_RunTimers();
/* _Add must precede _Modify because the same descriptor might
* be on both lists during the same pass through the machine,
* and to modify a descriptor before adding it would fail.
*/
_AddNewDescriptors();
_ModifyDescriptors();
switch (Poller) {
case Poller_Epoll:
_RunEpollOnce();
break;
case Poller_Kqueue:
_RunKqueueOnce();
break;
case Poller_Default:
_RunSelectOnce();
break;
}
_DispatchHeartbeats();
_CleanupSockets();
if (bTerminateSignalReceived)
return false;
return true;
}
#ifdef HAVE_EPOLL
typedef struct {
int epfd;
struct epoll_event *events;
int maxevents;
int timeout;
} epoll_args_t;
static void *nogvl_epoll_wait(void *args)
{
epoll_args_t *a = (epoll_args_t *)args;
return (void *) (uintptr_t) epoll_wait (a->epfd, a->events, a->maxevents, a->timeout);
}
#endif
/*****************************
EventMachine_t::_RunEpollOnce
*****************************/
void EventMachine_t::_RunEpollOnce()
{
#ifdef HAVE_EPOLL
assert (epfd != -1);
int s;
timeval tv = _TimeTilNextEvent();
#ifdef BUILD_FOR_RUBY
int ret = 0;
if ((ret = rb_wait_for_single_fd(epfd, RB_WAITFD_IN|RB_WAITFD_PRI, &tv)) < 1) {
if (ret == -1) {
assert(errno != EINVAL);
assert(errno != EBADF);
}
return;
}
epoll_args_t epoll_args = { epfd, epoll_events, MaxEvents, 0 };
s = (uintptr_t) rb_thread_call_without_gvl (nogvl_epoll_wait, &epoll_args, RUBY_UBF_IO, 0);
#else
int duration = 0;
duration = duration + (tv.tv_sec * 1000);
duration = duration + (tv.tv_usec / 1000);
s = epoll_wait (epfd, epoll_events, MaxEvents, duration);
#endif
if (s > 0) {
for (int i=0; i < s; i++) {
EventableDescriptor *ed = (EventableDescriptor*) epoll_events[i].data.ptr;
if (ed->IsWatchOnly() && ed->GetSocket() == INVALID_SOCKET)
continue;
assert(ed->GetSocket() != INVALID_SOCKET);
if (epoll_events[i].events & EPOLLIN)
ed->Read();
if (epoll_events[i].events & EPOLLOUT)
ed->Write();
if (epoll_events[i].events & (EPOLLERR | EPOLLHUP))
ed->HandleError();
}
}
else if (s < 0) {
// epoll_wait can fail on error in a handful of ways.
// If this happens, then wait for a little while to avoid busy-looping.
// If the error was EINTR, we probably caught SIGCHLD or something,
// so keep the wait short.
timeval tv = {0, ((errno == EINTR) ? 5 : 50) * 1000};
EmSelect (0, NULL, NULL, NULL, &tv);
}
#else
throw std::runtime_error ("epoll is not implemented on this platform");
#endif
}
#ifdef HAVE_KQUEUE
typedef struct {
int kqfd;
const struct kevent *changelist;
int nchanges;
struct kevent *eventlist;
int nevents;
const struct timespec *timeout;
} kevent_args_t;
static void *nogvl_kevent(void *args)
{
kevent_args_t *a = (kevent_args_t *)args;
return (void *) (uintptr_t) kevent (a->kqfd, a->changelist, a->nchanges, a->eventlist, a->nevents, a->timeout);
}
#endif
/******************************
EventMachine_t::_RunKqueueOnce
******************************/
#ifdef HAVE_KQUEUE
void EventMachine_t::_RunKqueueOnce()
{
assert (kqfd != -1);
int k;
timeval tv = _TimeTilNextEvent();
struct timespec ts;
ts.tv_sec = tv.tv_sec;
ts.tv_nsec = tv.tv_usec * 1000;
#ifdef BUILD_FOR_RUBY
int ret = 0;
if ((ret = rb_wait_for_single_fd(kqfd, RB_WAITFD_IN|RB_WAITFD_PRI, &tv)) < 1) {
if (ret == -1) {
assert(errno != EINVAL);
assert(errno != EBADF);
}
return;
}
ts.tv_sec = ts.tv_nsec = 0;
kevent_args_t kevent_args = { kqfd, NULL, 0, Karray, MaxEvents, &ts };
k = (uintptr_t) rb_thread_call_without_gvl (nogvl_kevent, &kevent_args, RUBY_UBF_IO, 0);
#else
k = kevent (kqfd, NULL, 0, Karray, MaxEvents, &ts);
#endif
struct kevent *ke = Karray;
while (k > 0) {
switch (ke->filter)
{
case EVFILT_VNODE:
_HandleKqueueFileEvent (ke);
break;
case EVFILT_PROC:
_HandleKqueuePidEvent (ke);
break;
case EVFILT_READ:
case EVFILT_WRITE:
EventableDescriptor *ed = (EventableDescriptor*) (ke->udata);
assert (ed);
if (ed->IsWatchOnly() && ed->GetSocket() == INVALID_SOCKET)
break;
if (ke->filter == EVFILT_READ)
ed->Read();
else if (ke->filter == EVFILT_WRITE)
ed->Write();
else
std::cerr << "Discarding unknown kqueue event " << ke->filter << std::endl;
break;
}
--k;
++ke;
}
#ifdef BUILD_FOR_RUBY
if (!rb_thread_alone()) {
rb_thread_schedule();
}
#endif
}
#else
void EventMachine_t::_RunKqueueOnce()
{
throw std::runtime_error ("kqueue is not implemented on this platform");
}
#endif
/*********************************
EventMachine_t::_TimeTilNextEvent
*********************************/
timeval EventMachine_t::_TimeTilNextEvent()
{
// 29jul11: Changed calculation base from MyCurrentLoopTime to the
// real time. As MyCurrentLoopTime is set at the beginning of an
// iteration and this calculation is done at the end, evenmachine
// will potentially oversleep by the amount of time the iteration
// took to execute.
uint64_t next_event = 0;
uint64_t current_time = GetRealTime();
if (!Heartbeats.empty()) {
std::multimap<uint64_t,EventableDescriptor*>::iterator heartbeats = Heartbeats.begin();
next_event = heartbeats->first;
}
if (!Timers.empty()) {
std::multimap<uint64_t,Timer_t>::iterator timers = Timers.begin();
if (next_event == 0 || timers->first < next_event)
next_event = timers->first;
}
if (!NewDescriptors.empty() || !ModifiedDescriptors.empty()) {
next_event = current_time;
}
timeval tv;
if (NumCloseScheduled > 0 || bTerminateSignalReceived) {
tv.tv_sec = tv.tv_usec = 0;
} else if (next_event == 0) {
tv = Quantum;
} else {
if (next_event > current_time) {
uint64_t duration = next_event - current_time;
tv.tv_sec = duration / 1000000;
tv.tv_usec = duration % 1000000;
} else {
tv.tv_sec = tv.tv_usec = 0;
}
}
return tv;
}
/*******************************
EventMachine_t::_CleanupSockets
*******************************/
void EventMachine_t::_CleanupSockets()
{
// TODO, rip this out and only delete the descriptors we know have died,
// rather than traversing the whole list.
// Modified 05Jan08 per suggestions by Chris Heath. It's possible that
// an EventableDescriptor will have a descriptor value of -1. That will
// happen if EventableDescriptor::Close was called on it. In that case,
// don't call epoll_ctl to remove the socket's filters from the epoll set.
// According to the epoll docs, this happens automatically when the
// descriptor is closed anyway. This is different from the case where
// the socket has already been closed but the descriptor in the ED object
// hasn't yet been set to INVALID_SOCKET.
// In kqueue, closing a descriptor automatically removes its event filters.
int i, j;
int nSockets = Descriptors.size();
for (i=0, j=0; i < nSockets; i++) {
EventableDescriptor *ed = Descriptors[i];
assert (ed);
if (ed->ShouldDelete()) {
#ifdef HAVE_EPOLL
if (Poller == Poller_Epoll) {
assert (epfd != -1);
if (ed->GetSocket() != INVALID_SOCKET) {
int e = epoll_ctl (epfd, EPOLL_CTL_DEL, ed->GetSocket(), ed->GetEpollEvent());
// ENOENT or EBADF are not errors because the socket may be already closed when we get here.
if (e && (errno != ENOENT) && (errno != EBADF) && (errno != EPERM)) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to delete epoll event: %s", strerror(errno));
throw std::runtime_error (buf);
}
}
ModifiedDescriptors.erase(ed);
}
#endif
delete ed;
}
else
Descriptors [j++] = ed;
}
while ((size_t)j < Descriptors.size())
Descriptors.pop_back();
}
/*********************************
EventMachine_t::_ModifyEpollEvent
*********************************/
#ifdef HAVE_EPOLL
void EventMachine_t::_ModifyEpollEvent (EventableDescriptor *ed)
{
if (Poller == Poller_Epoll) {
assert (epfd != -1);
assert (ed);
assert (ed->GetSocket() != INVALID_SOCKET);
int e = epoll_ctl (epfd, EPOLL_CTL_MOD, ed->GetSocket(), ed->GetEpollEvent());
if (e) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to modify epoll event: %s", strerror(errno));
throw std::runtime_error (buf);
}
}
}
#else
void EventMachine_t::_ModifyEpollEvent (EventableDescriptor *ed UNUSED) { }
#endif
/**************************
SelectData_t::SelectData_t
**************************/
SelectData_t::SelectData_t()
{
maxsocket = 0;
rb_fd_init (&fdreads);
rb_fd_init (&fdwrites);
rb_fd_init (&fderrors);
}
SelectData_t::~SelectData_t()
{
rb_fd_term (&fdreads);
rb_fd_term (&fdwrites);
rb_fd_term (&fderrors);
}
/*********************
SelectData_t::_Select
*********************/
int SelectData_t::_Select()
{
return EmSelect (maxsocket + 1, &fdreads, &fdwrites, &fderrors, &tv);
}
void SelectData_t::_Clear()
{
maxsocket = 0;
rb_fd_zero (&fdreads);
rb_fd_zero (&fdwrites);
rb_fd_zero (&fderrors);
}
/******************************
EventMachine_t::_RunSelectOnce
******************************/
void EventMachine_t::_RunSelectOnce()
{
// Crank the event machine once.
// If there are no descriptors to process, then sleep
// for a few hundred mills to avoid busy-looping.
// This is based on a select loop. Alternately provide epoll
// if we know we're running on a 2.6 kernel.
// epoll will be effective if we provide it as an alternative,
// however it has the same problem interoperating with Ruby
// threads that select does.
// Get ready for select()
SelectData->_Clear();
// Always read the loop-breaker reader.
// Changed 23Aug06, provisionally implemented for Windows with a UDP socket
// running on localhost with a randomly-chosen port. (*Puke*)
// Windows has a version of the Unix pipe() library function, but it doesn't
// give you back descriptors that are selectable.
rb_fd_set (LoopBreakerReader, &(SelectData->fdreads));
if (SelectData->maxsocket < LoopBreakerReader)
SelectData->maxsocket = LoopBreakerReader;
// prepare the sockets for reading and writing
size_t i;
for (i = 0; i < Descriptors.size(); i++) {
EventableDescriptor *ed = Descriptors[i];
assert (ed);
SOCKET sd = ed->GetSocket();
if (ed->IsWatchOnly() && sd == INVALID_SOCKET)
continue;
assert (sd != INVALID_SOCKET);
if (ed->SelectForRead())
rb_fd_set (sd, &(SelectData->fdreads));
if (ed->SelectForWrite())
rb_fd_set (sd, &(SelectData->fdwrites));
#ifdef OS_WIN32
/* 21Sep09: on windows, a non-blocking connect() that fails does not come up as writable.
Instead, it is added to the error set. See http://www.mail-archive.com/openssl-users@openssl.org/msg58500.html
*/
if (ed->IsConnectPending())
rb_fd_set (sd, &(SelectData->fderrors));
#endif
if (SelectData->maxsocket < sd)
SelectData->maxsocket = sd;
}
{ // read and write the sockets
SelectData->tv = _TimeTilNextEvent();
int s = SelectData->_Select();
if (s > 0) {
/* Changed 01Jun07. We used to handle the Loop-breaker right here.
* Now we do it AFTER all the regular descriptors. There's an
* incredibly important and subtle reason for this. Code on
* loop breakers is sometimes used to cause the reactor core to
* cycle (for example, to allow outbound network buffers to drain).
* If a loop-breaker handler reschedules itself (say, after determining
* that the write buffers are still too full), then it will execute
* IMMEDIATELY if _ReadLoopBreaker is done here instead of after
* the other descriptors are processed. That defeats the whole purpose.
*/
for (i=0; i < Descriptors.size(); i++) {
EventableDescriptor *ed = Descriptors[i];
assert (ed);
SOCKET sd = ed->GetSocket();
if (ed->IsWatchOnly() && sd == INVALID_SOCKET)
continue;
assert (sd != INVALID_SOCKET);
if (rb_fd_isset (sd, &(SelectData->fdwrites))) {
// Double-check SelectForWrite() still returns true. If not, one of the callbacks must have
// modified some value since we checked SelectForWrite() earlier in this method.
if (ed->SelectForWrite())
ed->Write();
}
if (rb_fd_isset (sd, &(SelectData->fdreads)))
ed->Read();
if (rb_fd_isset (sd, &(SelectData->fderrors)))
ed->HandleError();
}
if (rb_fd_isset (LoopBreakerReader, &(SelectData->fdreads)))
_ReadLoopBreaker();
}
else if (s < 0) {
switch (errno) {
case EBADF:
_CleanBadDescriptors();
break;
case EINVAL:
throw std::runtime_error ("Somehow EM passed an invalid nfds or invalid timeout to select(2), please report this!");
break;
default:
// select can fail on error in a handful of ways.
// If this happens, then wait for a little while to avoid busy-looping.
// If the error was EINTR, we probably caught SIGCHLD or something,
// so keep the wait short.
timeval tv = {0, ((errno == EINTR) ? 5 : 50) * 1000};
EmSelect (0, NULL, NULL, NULL, &tv);
}
}
}
}
void EventMachine_t::_CleanBadDescriptors()
{
size_t i;
for (i = 0; i < Descriptors.size(); i++) {
EventableDescriptor *ed = Descriptors[i];
if (ed->ShouldDelete())
continue;
if (rb_wait_for_single_fd(ed->GetSocket(), RB_WAITFD_PRI, NULL) < 0) {
if (errno == EBADF)
ed->ScheduleClose(false);
}
}
}
/********************************
EventMachine_t::_ReadLoopBreaker
********************************/
void EventMachine_t::_ReadLoopBreaker()
{
/* The loop breaker has selected readable.
* Read it ONCE (it may block if we try to read it twice)
* and send a loop-break event back to user code.
*/
char buffer [1024];
(void)read (LoopBreakerReader, buffer, sizeof(buffer));
if (EventCallback)
(*EventCallback)(0, EM_LOOPBREAK_SIGNAL, "", 0);
}
/**************************
EventMachine_t::_RunTimers
**************************/
void EventMachine_t::_RunTimers()
{
// These are caller-defined timer handlers.
// We rely on the fact that multimaps sort by their keys to avoid
// inspecting the whole list every time we come here.
// Just keep inspecting and processing the list head until we hit
// one that hasn't expired yet.
while (true) {
std::multimap<uint64_t,Timer_t>::iterator i = Timers.begin();
if (i == Timers.end())
break;
if (i->first > MyCurrentLoopTime)
break;
if (EventCallback)
(*EventCallback) (0, EM_TIMER_FIRED, NULL, i->second.GetBinding());
Timers.erase (i);
}
}
/*********************************************
EventMachine_t::_GetNumberOfOutstandingTimers
*********************************************/
size_t EventMachine_t::GetTimerCount()
{
return Timers.size();
}
/***********************************
EventMachine_t::InstallOneshotTimer
***********************************/
const uintptr_t EventMachine_t::InstallOneshotTimer (uint64_t milliseconds)
{
if (Timers.size() > MaxOutstandingTimers)
return false;
uint64_t fire_at = GetRealTime();
fire_at += ((uint64_t)milliseconds) * 1000LL;
Timer_t t;
#ifndef HAVE_MAKE_PAIR
std::multimap<uint64_t,Timer_t>::iterator i = Timers.insert (std::multimap<uint64_t,Timer_t>::value_type (fire_at, t));
#else
std::multimap<uint64_t,Timer_t>::iterator i = Timers.insert (std::make_pair (fire_at, t));
#endif
return i->second.GetBinding();
}
/*******************************
EventMachine_t::ConnectToServer
*******************************/
const uintptr_t EventMachine_t::ConnectToServer (const char *bind_addr, int bind_port, const char *server, int port)
{
/* We want to spend no more than a few seconds waiting for a connection
* to a remote host. So we use a nonblocking connect.
* Linux disobeys the usual rules for nonblocking connects.
* Per Stevens (UNP p.410), you expect a nonblocking connect to select
* both readable and writable on error, and not to return EINPROGRESS
* if the connect can be fulfilled immediately. Linux violates both
* of these expectations.
* Any kind of nonblocking connect on Linux returns EINPROGRESS.
* The socket will then return writable when the disposition of the
* connect is known, but it will not also be readable in case of
* error! Weirdly, it will be readable in case there is data to read!!!
* (Which can happen with protocols like SSH and SMTP.)
* I suppose if you were so inclined you could consider this logical,
* but it's not the way Unix has historically done it.
* So we ignore the readable flag and read getsockopt to see if there
* was an error connecting. A select timeout works as expected.
* In regard to getsockopt: Linux does the Berkeley-style thing,
* not the Solaris-style, and returns zero with the error code in
* the error parameter.
* Return the binding-text of the newly-created pending connection,
* or NULL if there was a problem.
*/
if (!server || !*server || !port)
throw std::runtime_error ("invalid server or port");
struct sockaddr_storage bind_as;
size_t bind_as_len = sizeof bind_as;
int gai = name2address (server, port, SOCK_STREAM, (struct sockaddr *)&bind_as, &bind_as_len);
if (gai != 0) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to resolve address: %s", gai_strerror(gai));
throw std::runtime_error (buf);
}
SOCKET sd = EmSocket (bind_as.ss_family, SOCK_STREAM, 0);
if (sd == INVALID_SOCKET) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to create new socket: %s", strerror(errno));
throw std::runtime_error (buf);
}
// From here on, ALL error returns must close the socket.
// Set the new socket nonblocking.
if (!SetSocketNonblocking (sd)) {
close (sd);
throw std::runtime_error ("unable to set socket as non-blocking");
}
// Disable slow-start (Nagle algorithm).
int one = 1;
setsockopt (sd, IPPROTO_TCP, TCP_NODELAY, (char*) &one, sizeof(one));
// Set reuseaddr to improve performance on restarts
setsockopt (sd, SOL_SOCKET, SO_REUSEADDR, (char*) &one, sizeof(one));
if (bind_addr) {
struct sockaddr_storage bind_to;
size_t bind_to_len = sizeof bind_to;
gai = name2address (bind_addr, bind_port, SOCK_STREAM, (struct sockaddr *)&bind_to, &bind_to_len);
if (gai != 0) {
close (sd);
char buf [200];
snprintf (buf, sizeof(buf)-1, "invalid bind address: %s", gai_strerror(gai));
throw std::runtime_error (buf);
}
if (bind (sd, (struct sockaddr *)&bind_to, bind_to_len) < 0) {
close (sd);
throw std::runtime_error ("couldn't bind to address");
}
}
uintptr_t out = 0;
#ifdef OS_UNIX
int e_reason = 0;
if (connect (sd, (struct sockaddr *)&bind_as, bind_as_len) == 0) {
// This is a connect success, which Linux appears
// never to give when the socket is nonblocking,
// even if the connection is intramachine or to
// localhost.
/* Changed this branch 08Aug06. Evidently some kernels
* (FreeBSD for example) will actually return success from
* a nonblocking connect. This is a pretty simple case,
* just set up the new connection and clear the pending flag.
* Thanks to Chris Ochs for helping track this down.
* This branch never gets taken on Linux or (oddly) OSX.
* The original behavior was to throw an unimplemented,
* which the user saw as a fatal exception. Very unfriendly.
*
* Tweaked 10Aug06. Even though the connect disposition is
* known, we still set the connect-pending flag. That way
* some needed initialization will happen in the ConnectionDescriptor.
* (To wit, the ConnectionCompleted event gets sent to the client.)
*/
ConnectionDescriptor *cd = new ConnectionDescriptor (sd, this);
if (!cd)
throw std::runtime_error ("no connection allocated");
cd->SetConnectPending (true);
Add (cd);
out = cd->GetBinding();
}
else if (errno == EINPROGRESS) {
// Errno will generally always be EINPROGRESS, but on Linux
// we have to look at getsockopt to be sure what really happened.
int error = 0;
socklen_t len;
len = sizeof(error);
int o = getsockopt (sd, SOL_SOCKET, SO_ERROR, &error, &len);
if ((o == 0) && (error == 0)) {
// Here, there's no disposition.
// Put the connection on the stack and wait for it to complete
// or time out.
ConnectionDescriptor *cd = new ConnectionDescriptor (sd, this);
if (!cd)
throw std::runtime_error ("no connection allocated");
cd->SetConnectPending (true);
Add (cd);
out = cd->GetBinding();
} else {
// Fall through to the !out case below.
e_reason = error;
}
}
else {
// The error from connect was something other then EINPROGRESS (EHOSTDOWN, etc).
// Fall through to the !out case below
e_reason = errno;
}
if (!out) {
/* This could be connection refused or some such thing.
* We will come here on Linux if a localhost connection fails.
* Changed 16Jul06: Originally this branch was a no-op, and
* we'd drop down to the end of the method, close the socket,
* and return NULL, which would cause the caller to GET A
* FATAL EXCEPTION. Now we keep the socket around but schedule an
* immediate close on it, so the caller will get a close-event
* scheduled on it. This was only an issue for localhost connections
* to non-listening ports. We may eventually need to revise this
* revised behavior, in case it causes problems like making it hard
* for people to know that a failure occurred.
*/
ConnectionDescriptor *cd = new ConnectionDescriptor (sd, this);
if (!cd)
throw std::runtime_error ("no connection allocated");
cd->SetUnbindReasonCode (e_reason);
cd->ScheduleClose (false);
Add (cd);
out = cd->GetBinding();
}
#endif
#ifdef OS_WIN32
if (connect (sd, (struct sockaddr *)&bind_as, bind_as_len) == 0) {
// This is a connect success, which Windows appears
// never to give when the socket is nonblocking,
// even if the connection is intramachine or to
// localhost.
throw std::runtime_error ("unimplemented");
}
else if (WSAGetLastError() == WSAEWOULDBLOCK) {
// Here, there's no disposition.
// Windows appears not to surface refused connections or
// such stuff at this point.
// Put the connection on the stack and wait for it to complete
// or time out.
ConnectionDescriptor *cd = new ConnectionDescriptor (sd, this);
if (!cd)
throw std::runtime_error ("no connection allocated");
cd->SetConnectPending (true);
Add (cd);
out = cd->GetBinding();
}
else {
// The error from connect was something other then WSAEWOULDBLOCK.
}
#endif
if (!out)
close (sd);
return out;
}
/***********************************
EventMachine_t::ConnectToUnixServer
***********************************/
#ifdef OS_UNIX
const uintptr_t EventMachine_t::ConnectToUnixServer (const char *server)
{
/* Connect to a Unix-domain server, which by definition is running
* on the same host.
* There is no meaningful implementation on Windows.
* There's no need to do a nonblocking connect, since the connection
* is always local and can always be fulfilled immediately.
*/
uintptr_t out = 0;
if (!server || !*server)
return 0;
sockaddr_un pun;
memset (&pun, 0, sizeof(pun));
pun.sun_family = AF_LOCAL;
// You ordinarily expect the server name field to be at least 1024 bytes long,
// but on Linux it can be MUCH shorter.
if (strlen(server) >= sizeof(pun.sun_path))
throw std::runtime_error ("unix-domain server name is too long");
strcpy (pun.sun_path, server);
SOCKET fd = EmSocket (AF_LOCAL, SOCK_STREAM, 0);
if (fd == INVALID_SOCKET)
return 0;
// From here on, ALL error returns must close the socket.
// NOTE: At this point, the socket is still a blocking socket.
if (connect (fd, (struct sockaddr*)&pun, sizeof(pun)) != 0) {
close (fd);
return 0;
}
// Set the newly-connected socket nonblocking.
if (!SetSocketNonblocking (fd)) {
close (fd);
return 0;
}
// Set up a connection descriptor and add it to the event-machine.
// Observe, even though we know the connection status is connect-success,
// we still set the "pending" flag, so some needed initializations take
// place.
ConnectionDescriptor *cd = new ConnectionDescriptor (fd, this);
if (!cd)
throw std::runtime_error ("no connection allocated");
cd->SetConnectPending (true);
Add (cd);
out = cd->GetBinding();
if (!out)
close (fd);
return out;
}
#else
const uintptr_t EventMachine_t::ConnectToUnixServer (const char *server UNUSED)
{
throw std::runtime_error ("unix-domain connection unavailable on this platform");
}
#endif
/************************
EventMachine_t::AttachFD
************************/
const uintptr_t EventMachine_t::AttachFD (SOCKET fd, bool watch_mode)
{
#ifdef OS_UNIX
if (fcntl(fd, F_GETFL, 0) < 0) {
if (errno) {
throw std::runtime_error (strerror(errno));
} else {
throw std::runtime_error ("invalid file descriptor");
}
}
#endif
#ifdef OS_WIN32
// TODO: add better check for invalid file descriptors (see ioctlsocket or getsockopt)
if (fd == INVALID_SOCKET)
throw std::runtime_error ("invalid file descriptor");
#endif
{// Check for duplicate descriptors
size_t i;
for (i = 0; i < Descriptors.size(); i++) {
EventableDescriptor *ed = Descriptors[i];
assert (ed);
if (ed->GetSocket() == fd)
throw std::runtime_error ("adding existing descriptor");
}
for (i = 0; i < NewDescriptors.size(); i++) {
EventableDescriptor *ed = NewDescriptors[i];
assert (ed);
if (ed->GetSocket() == fd)
throw std::runtime_error ("adding existing new descriptor");
}
}
if (!watch_mode)
SetSocketNonblocking(fd);
ConnectionDescriptor *cd = new ConnectionDescriptor (fd, this);
if (!cd)
throw std::runtime_error ("no connection allocated");
cd->SetAttached(true);
cd->SetWatchOnly(watch_mode);
cd->SetConnectPending (false);
Add (cd);
const uintptr_t out = cd->GetBinding();
return out;
}
/************************
EventMachine_t::DetachFD
************************/
int EventMachine_t::DetachFD (EventableDescriptor *ed)
{
if (!ed)
throw std::runtime_error ("detaching bad descriptor");
SOCKET fd = ed->GetSocket();
#ifdef HAVE_EPOLL
if (Poller == Poller_Epoll) {
if (ed->GetSocket() != INVALID_SOCKET) {
assert (epfd != -1);
int e = epoll_ctl (epfd, EPOLL_CTL_DEL, ed->GetSocket(), ed->GetEpollEvent());
// ENOENT or EBADF are not errors because the socket may be already closed when we get here.
if (e && (errno != ENOENT) && (errno != EBADF)) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to delete epoll event: %s", strerror(errno));
throw std::runtime_error (buf);
}
}
}
#endif
#ifdef HAVE_KQUEUE
if (Poller == Poller_Kqueue) {
// remove any read/write events for this fd
struct kevent k;
#ifdef __NetBSD__
EV_SET (&k, ed->GetSocket(), EVFILT_READ | EVFILT_WRITE, EV_DELETE, 0, 0, (intptr_t)ed);
#else
EV_SET (&k, ed->GetSocket(), EVFILT_READ | EVFILT_WRITE, EV_DELETE, 0, 0, ed);
#endif
int t = kevent (kqfd, &k, 1, NULL, 0, NULL);
if (t < 0 && (errno != ENOENT) && (errno != EBADF)) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to delete kqueue event: %s", strerror(errno));
throw std::runtime_error (buf);
}
}
#endif
// Prevent the descriptor from being modified, in case DetachFD was called from a timer or next_tick
ModifiedDescriptors.erase (ed);
// Prevent the descriptor from being added, in case DetachFD was called in the same tick as AttachFD
for (size_t i = 0; i < NewDescriptors.size(); i++) {
if (ed == NewDescriptors[i]) {
NewDescriptors.erase(NewDescriptors.begin() + i);
break;
}
}
// Set MySocket = INVALID_SOCKET so ShouldDelete() is true (and the descriptor gets deleted and removed),
// and also to prevent anyone from calling close() on the detached fd
ed->SetSocketInvalid();
return fd;
}
/************
name2address
************/
int EventMachine_t::name2address (const char *server, int port, int socktype, struct sockaddr *addr, size_t *addr_len)
{
if (!server || !*server)
server = "0.0.0.0";
struct addrinfo *ai;
struct addrinfo hints;
memset (&hints, 0, sizeof(hints));
hints.ai_socktype = socktype;
hints.ai_family = AF_UNSPEC;
hints.ai_flags = AI_NUMERICSERV | AI_ADDRCONFIG;
char portstr[12];
snprintf(portstr, sizeof(portstr), "%u", port);
int gai = getaddrinfo (server, portstr, &hints, &ai);
if (gai == 0) {
assert (ai->ai_addrlen <= *addr_len);
memcpy (addr, ai->ai_addr, ai->ai_addrlen);
*addr_len = ai->ai_addrlen;
freeaddrinfo(ai);
}
return gai;
}
/*******************************
EventMachine_t::CreateTcpServer
*******************************/
const uintptr_t EventMachine_t::CreateTcpServer (const char *server, int port)
{
/* Create a TCP-acceptor (server) socket and add it to the event machine.
* Return the binding of the new acceptor to the caller.
* This binding will be referenced when the new acceptor sends events
* to indicate accepted connections.
*/
struct sockaddr_storage bind_here;
size_t bind_here_len = sizeof bind_here;
if (0 != name2address (server, port, SOCK_STREAM, (struct sockaddr *)&bind_here, &bind_here_len))
return 0;
SOCKET sd_accept = EmSocket (bind_here.ss_family, SOCK_STREAM, 0);
if (sd_accept == INVALID_SOCKET) {
goto fail;
}
{ // set reuseaddr to improve performance on restarts.
int oval = 1;
if (setsockopt (sd_accept, SOL_SOCKET, SO_REUSEADDR, (char*)&oval, sizeof(oval)) < 0) {
//__warning ("setsockopt failed while creating listener","");
goto fail;
}
}
{ // set CLOEXEC. Only makes sense on Unix
#ifdef OS_UNIX
int cloexec = fcntl (sd_accept, F_GETFD, 0);
assert (cloexec >= 0);
cloexec |= FD_CLOEXEC;
fcntl (sd_accept, F_SETFD, cloexec);
#endif
}
if (bind (sd_accept, (struct sockaddr *)&bind_here, bind_here_len)) {
//__warning ("binding failed");
goto fail;
}
if (listen (sd_accept, 100)) {
//__warning ("listen failed");
goto fail;
}
return AttachSD(sd_accept);
fail:
if (sd_accept != INVALID_SOCKET)
close (sd_accept);
return 0;
}
/**********************************
EventMachine_t::OpenDatagramSocket
**********************************/
const uintptr_t EventMachine_t::OpenDatagramSocket (const char *address, int port)
{
uintptr_t output_binding = 0;
struct sockaddr_storage bind_here;
size_t bind_here_len = sizeof bind_here;
if (0 != name2address (address, port, SOCK_DGRAM, (struct sockaddr *)&bind_here, &bind_here_len))
return 0;
// from here on, early returns must close the socket!
SOCKET sd = EmSocket (bind_here.ss_family, SOCK_DGRAM, 0);
if (sd == INVALID_SOCKET)
goto fail;
{ // set the SO_REUSEADDR on the socket before we bind, otherwise it won't work for a second one
int oval = 1;
if (setsockopt (sd, SOL_SOCKET, SO_REUSEADDR, (char*)&oval, sizeof(oval)) < 0)
goto fail;
}
// Set the new socket nonblocking.
if (!SetSocketNonblocking (sd))
goto fail;
if (bind (sd, (struct sockaddr *)&bind_here, bind_here_len) != 0)
goto fail;
{ // Looking good.
DatagramDescriptor *ds = new DatagramDescriptor (sd, this);
if (!ds)
throw std::runtime_error ("unable to allocate datagram-socket");
Add (ds);
output_binding = ds->GetBinding();
}
return output_binding;
fail:
if (sd != INVALID_SOCKET)
close (sd);
return 0;
}
/*******************
EventMachine_t::Add
*******************/
void EventMachine_t::Add (EventableDescriptor *ed)
{
if (!ed)
throw std::runtime_error ("added bad descriptor");
ed->SetEventCallback (EventCallback);
NewDescriptors.push_back (ed);
}
/*******************************
EventMachine_t::ArmKqueueWriter
*******************************/
#ifdef HAVE_KQUEUE
void EventMachine_t::ArmKqueueWriter (EventableDescriptor *ed)
{
if (Poller == Poller_Kqueue) {
if (!ed)
throw std::runtime_error ("added bad descriptor");
struct kevent k;
#ifdef __NetBSD__
EV_SET (&k, ed->GetSocket(), EVFILT_WRITE, EV_ADD | EV_ONESHOT, 0, 0, (intptr_t)ed);
#else
EV_SET (&k, ed->GetSocket(), EVFILT_WRITE, EV_ADD | EV_ONESHOT, 0, 0, ed);
#endif
int t = kevent (kqfd, &k, 1, NULL, 0, NULL);
if (t < 0) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "arm kqueue writer failed on %d: %s", ed->GetSocket(), strerror(errno));
throw std::runtime_error (buf);
}
}
}
#else
void EventMachine_t::ArmKqueueWriter (EventableDescriptor *ed UNUSED) { }
#endif
/*******************************
EventMachine_t::ArmKqueueReader
*******************************/
#ifdef HAVE_KQUEUE
void EventMachine_t::ArmKqueueReader (EventableDescriptor *ed)
{
if (Poller == Poller_Kqueue) {
if (!ed)
throw std::runtime_error ("added bad descriptor");
struct kevent k;
#ifdef __NetBSD__
EV_SET (&k, ed->GetSocket(), EVFILT_READ, EV_ADD, 0, 0, (intptr_t)ed);
#else
EV_SET (&k, ed->GetSocket(), EVFILT_READ, EV_ADD, 0, 0, ed);
#endif
int t = kevent (kqfd, &k, 1, NULL, 0, NULL);
if (t < 0) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "arm kqueue reader failed on %d: %s", ed->GetSocket(), strerror(errno));
throw std::runtime_error (buf);
}
}
}
#else
void EventMachine_t::ArmKqueueReader (EventableDescriptor *ed UNUSED) { }
#endif
/**********************************
EventMachine_t::_AddNewDescriptors
**********************************/
void EventMachine_t::_AddNewDescriptors()
{
/* Avoid adding descriptors to the main descriptor list
* while we're actually traversing the list.
* Any descriptors that are added as a result of processing timers
* or acceptors should go on a temporary queue and then added
* while we're not traversing the main list.
* Also, it (rarely) happens that a newly-created descriptor
* is immediately scheduled to close. It might be a good
* idea not to bother scheduling these for I/O but if
* we do that, we might bypass some important processing.
*/
for (size_t i = 0; i < NewDescriptors.size(); i++) {
EventableDescriptor *ed = NewDescriptors[i];
if (ed == NULL)
throw std::runtime_error ("adding bad descriptor");
#if HAVE_EPOLL
if (Poller == Poller_Epoll) {
assert (epfd != -1);
int e = epoll_ctl (epfd, EPOLL_CTL_ADD, ed->GetSocket(), ed->GetEpollEvent());
if (e) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to add new descriptor: %s", strerror(errno));
throw std::runtime_error (buf);
}
}
#endif
#if HAVE_KQUEUE
/*
if (Poller == Poller_Kqueue) {
// INCOMPLETE. Some descriptors don't want to be readable.
assert (kqfd != -1);
struct kevent k;
#ifdef __NetBSD__
EV_SET (&k, ed->GetSocket(), EVFILT_READ, EV_ADD, 0, 0, (intptr_t)ed);
#else
EV_SET (&k, ed->GetSocket(), EVFILT_READ, EV_ADD, 0, 0, ed);
#endif
int t = kevent (kqfd, &k, 1, NULL, 0, NULL);
assert (t == 0);
}
*/
#endif
QueueHeartbeat(ed);
Descriptors.push_back (ed);
}
NewDescriptors.clear();
}
/**********************************
EventMachine_t::_ModifyDescriptors
**********************************/
void EventMachine_t::_ModifyDescriptors()
{
/* For implementations which don't level check every descriptor on
* every pass through the machine, as select does.
* If we're not selecting, then descriptors need a way to signal to the
* machine that their readable or writable status has changed.
* That's what the ::Modify call is for. We do it this way to avoid
* modifying descriptors during the loop traversal, where it can easily
* happen that an object (like a UDP socket) gets data written on it by
* the application during #post_init. That would take place BEFORE the
* descriptor even gets added to the epoll descriptor, so the modify
* operation will crash messily.
* Another really messy possibility is for a descriptor to put itself
* on the Modified list, and then get deleted before we get here.
* Remember, deletes happen after the I/O traversal and before the
* next pass through here. So we have to make sure when we delete a
* descriptor to remove it from the Modified list.
*/
#ifdef HAVE_EPOLL
if (Poller == Poller_Epoll) {
std::set<EventableDescriptor*>::iterator i = ModifiedDescriptors.begin();
while (i != ModifiedDescriptors.end()) {
assert (*i);
_ModifyEpollEvent (*i);
++i;
}
}
#endif
#ifdef HAVE_KQUEUE
if (Poller == Poller_Kqueue) {
std::set<EventableDescriptor*>::iterator i = ModifiedDescriptors.begin();
while (i != ModifiedDescriptors.end()) {
assert (*i);
if ((*i)->GetKqueueArmWrite())
ArmKqueueWriter (*i);
++i;
}
}
#endif
ModifiedDescriptors.clear();
}
/**********************
EventMachine_t::Modify
**********************/
void EventMachine_t::Modify (EventableDescriptor *ed)
{
if (!ed)
throw std::runtime_error ("modified bad descriptor");
ModifiedDescriptors.insert (ed);
}
/***********************
EventMachine_t::Deregister
***********************/
void EventMachine_t::Deregister (EventableDescriptor *ed)
{
if (!ed)
throw std::runtime_error ("modified bad descriptor");
#ifdef HAVE_EPOLL
// cut/paste from _CleanupSockets(). The error handling could be
// refactored out of there, but it is cut/paste all over the
// file already.
if (Poller == Poller_Epoll) {
assert (epfd != -1);
assert (ed->GetSocket() != INVALID_SOCKET);
int e = epoll_ctl (epfd, EPOLL_CTL_DEL, ed->GetSocket(), ed->GetEpollEvent());
// ENOENT or EBADF are not errors because the socket may be already closed when we get here.
if (e && (errno != ENOENT) && (errno != EBADF) && (errno != EPERM)) {
char buf [200];
snprintf (buf, sizeof(buf)-1, "unable to delete epoll event: %s", strerror(errno));
throw std::runtime_error (buf);
}
ModifiedDescriptors.erase(ed);
}
#endif
#ifdef HAVE_KQUEUE
if (Poller == Poller_Kqueue) {
assert (ed->GetSocket() != INVALID_SOCKET);
ModifiedDescriptors.erase(ed);
}
#endif
}
/**************************************
EventMachine_t::CreateUnixDomainServer
**************************************/
#ifdef OS_UNIX
const uintptr_t EventMachine_t::CreateUnixDomainServer (const char *filename)
{
/* Create a UNIX-domain acceptor (server) socket and add it to the event machine.
* Return the binding of the new acceptor to the caller.
* This binding will be referenced when the new acceptor sends events
* to indicate accepted connections.
* THERE IS NO MEANINGFUL IMPLEMENTATION ON WINDOWS.
*/
struct sockaddr_un s_sun;
SOCKET sd_accept = EmSocket (AF_LOCAL, SOCK_STREAM, 0);
if (sd_accept == INVALID_SOCKET) {
goto fail;
}
if (!filename || !*filename)
goto fail;
unlink (filename);
bzero (&s_sun, sizeof(s_sun));
s_sun.sun_family = AF_LOCAL;
strncpy (s_sun.sun_path, filename, sizeof(s_sun.sun_path)-1);
// don't bother with reuseaddr for a local socket.
{ // set CLOEXEC. Only makes sense on Unix
#ifdef OS_UNIX
int cloexec = fcntl (sd_accept, F_GETFD, 0);
assert (cloexec >= 0);
cloexec |= FD_CLOEXEC;
fcntl (sd_accept, F_SETFD, cloexec);
#endif
}
if (bind (sd_accept, (struct sockaddr*)&s_sun, sizeof(s_sun))) {
//__warning ("binding failed");
goto fail;
}
if (listen (sd_accept, 100)) {
//__warning ("listen failed");
goto fail;
}
return AttachSD(sd_accept);
fail:
if (sd_accept != INVALID_SOCKET)
close (sd_accept);
return 0;
}
#else
const uintptr_t EventMachine_t::CreateUnixDomainServer (const char *filename UNUSED)
{
throw std::runtime_error ("unix-domain server unavailable on this platform");
}
#endif
/**************************************
EventMachine_t::AttachSD
**************************************/
const uintptr_t EventMachine_t::AttachSD (SOCKET sd_accept)
{
uintptr_t output_binding = 0;
{
// Set the acceptor non-blocking.
// THIS IS CRUCIALLY IMPORTANT because we read it in a select loop.
if (!SetSocketNonblocking (sd_accept)) {
//int val = fcntl (sd_accept, F_GETFL, 0);
//if (fcntl (sd_accept, F_SETFL, val | O_NONBLOCK) == -1) {
goto fail;
}
}
{ // Looking good.
AcceptorDescriptor *ad = new AcceptorDescriptor (sd_accept, this);
if (!ad)
throw std::runtime_error ("unable to allocate acceptor");
Add (ad);
output_binding = ad->GetBinding();
}
return output_binding;
fail:
if (sd_accept != INVALID_SOCKET)
close (sd_accept);
return 0;
}
/**************************
EventMachine_t::Socketpair
**************************/
#ifdef OS_UNIX
const uintptr_t EventMachine_t::Socketpair (char * const * cmd_strings)
{
// Make sure the incoming array of command strings is sane.
if (!cmd_strings)
return 0;
int j;
for (j=0; j < 2048 && cmd_strings[j]; j++)
;
if ((j==0) || (j==2048))
return 0;
uintptr_t output_binding = 0;
int sv[2];
if (socketpair (AF_LOCAL, SOCK_STREAM, 0, sv) < 0)
return 0;
// from here, all early returns must close the pair of sockets.
// Set the parent side of the socketpair nonblocking.
// We don't care about the child side, and most child processes will expect their
// stdout to be blocking. Thanks to Duane Johnson and Bill Kelly for pointing this out.
// Obviously DON'T set CLOEXEC.
if (!SetSocketNonblocking (sv[0])) {
close (sv[0]);
close (sv[1]);
return 0;
}
pid_t f = fork();
if (f > 0) {
close (sv[1]);
PipeDescriptor *pd = new PipeDescriptor (sv[0], f, this);
if (!pd)
throw std::runtime_error ("unable to allocate pipe");
Add (pd);
output_binding = pd->GetBinding();
}
else if (f == 0) {
close (sv[0]);
dup2 (sv[1], STDIN_FILENO);
close (sv[1]);
dup2 (STDIN_FILENO, STDOUT_FILENO);
execvp (cmd_strings[0], cmd_strings+1);
exit (-1); // end the child process if the exec doesn't work.
}
else
throw std::runtime_error ("no fork");
return output_binding;
}
#else
const uintptr_t EventMachine_t::Socketpair (char * const * cmd_strings UNUSED)
{
throw std::runtime_error ("socketpair is currently unavailable on this platform");
}
#endif
/****************************
EventMachine_t::OpenKeyboard
****************************/
const uintptr_t EventMachine_t::OpenKeyboard()
{
KeyboardDescriptor *kd = new KeyboardDescriptor (this);
if (!kd)
throw std::runtime_error ("no keyboard-object allocated");
Add (kd);
return kd->GetBinding();
}
/**********************************
EventMachine_t::GetConnectionCount
**********************************/
int EventMachine_t::GetConnectionCount ()
{
int i = 0;
// Subtract one for epoll or kqueue because of the LoopbreakDescriptor
if (Poller == Poller_Epoll || Poller == Poller_Kqueue)
i = 1;
return Descriptors.size() + NewDescriptors.size() - i;
}
/************************
EventMachine_t::WatchPid
************************/
#ifdef HAVE_KQUEUE
const uintptr_t EventMachine_t::WatchPid (int pid)
{
if (Poller != Poller_Kqueue)
throw std::runtime_error("must enable kqueue (EM.kqueue=true) for pid watching support");
struct kevent event;
int kqres;
EV_SET(&event, pid, EVFILT_PROC, EV_ADD, NOTE_EXIT | NOTE_FORK, 0, 0);
// Attempt to register the event
kqres = kevent(kqfd, &event, 1, NULL, 0, NULL);
if (kqres == -1) {
char errbuf[200];
sprintf(errbuf, "failed to register file watch descriptor with kqueue: %s", strerror(errno));
throw std::runtime_error(errbuf);
}
Bindable_t* b = new Bindable_t();
Pids.insert(std::make_pair (pid, b));
return b->GetBinding();
}
#else
const uintptr_t EventMachine_t::WatchPid (int pid UNUSED)
{
throw std::runtime_error("no pid watching support on this system");
}
#endif
/**************************
EventMachine_t::UnwatchPid
**************************/
void EventMachine_t::UnwatchPid (int pid)
{
Bindable_t *b = Pids[pid];
assert(b);
Pids.erase(pid);
#ifdef HAVE_KQUEUE
struct kevent k;
EV_SET(&k, pid, EVFILT_PROC, EV_DELETE, 0, 0, 0);
/*int t =*/ kevent (kqfd, &k, 1, NULL, 0, NULL);
// t==-1 if the process already exited; ignore this for now
#endif
if (EventCallback)
(*EventCallback)(b->GetBinding(), EM_CONNECTION_UNBOUND, NULL, 0);
delete b;
}
void EventMachine_t::UnwatchPid (const uintptr_t sig)
{
for(std::map<int, Bindable_t*>::iterator i=Pids.begin(); i != Pids.end(); i++)
{
if (i->second->GetBinding() == sig) {
UnwatchPid (i->first);
return;
}
}
throw std::runtime_error("attempted to remove invalid pid signature");
}
/*************************
EventMachine_t::WatchFile
*************************/
const uintptr_t EventMachine_t::WatchFile (const char *fpath)
{
struct stat sb;
int sres;
int wd = -1;
sres = stat(fpath, &sb);
if (sres == -1) {
char errbuf[300];
sprintf(errbuf, "error registering file %s for watching: %s", fpath, strerror(errno));
throw std::runtime_error(errbuf);
}
#ifdef HAVE_INOTIFY
if (!inotify) {
inotify = new InotifyDescriptor(this);
assert (inotify);
Add(inotify);
}
wd = inotify_add_watch(inotify->GetSocket(), fpath,
IN_MODIFY | IN_DELETE_SELF | IN_MOVE_SELF | IN_CREATE | IN_DELETE | IN_MOVE) ;
if (wd == -1) {
char errbuf[300];
sprintf(errbuf, "failed to open file %s for registering with inotify: %s", fpath, strerror(errno));
throw std::runtime_error(errbuf);
}
#endif
#ifdef HAVE_KQUEUE
if (Poller != Poller_Kqueue)
throw std::runtime_error("must enable kqueue (EM.kqueue=true) for file watching support");
// With kqueue we have to open the file first and use the resulting fd to register for events
wd = open(fpath, O_RDONLY);
if (wd == -1) {
char errbuf[300];
sprintf(errbuf, "failed to open file %s for registering with kqueue: %s", fpath, strerror(errno));
throw std::runtime_error(errbuf);
}
_RegisterKqueueFileEvent(wd);
#endif
if (wd != -1) {
Bindable_t* b = new Bindable_t();
Files.insert(std::make_pair (wd, b));
return b->GetBinding();
}
throw std::runtime_error("no file watching support on this system"); // is this the right thing to do?
}
/***************************
EventMachine_t::UnwatchFile
***************************/
void EventMachine_t::UnwatchFile (int wd)
{
Bindable_t *b = Files[wd];
assert(b);
Files.erase(wd);
#ifdef HAVE_INOTIFY
inotify_rm_watch(inotify->GetSocket(), wd);
#elif HAVE_KQUEUE
// With kqueue, closing the monitored fd automatically clears all registered events for it
close(wd);
#endif
if (EventCallback)
(*EventCallback)(b->GetBinding(), EM_CONNECTION_UNBOUND, NULL, 0);
delete b;
}
void EventMachine_t::UnwatchFile (const uintptr_t sig)
{
for(std::map<int, Bindable_t*>::iterator i=Files.begin(); i != Files.end(); i++)
{
if (i->second->GetBinding() == sig) {
UnwatchFile (i->first);
return;
}
}
throw std::runtime_error("attempted to remove invalid watch signature");
}
/***********************************
EventMachine_t::_ReadInotify_Events
************************************/
void EventMachine_t::_ReadInotifyEvents()
{
#ifdef HAVE_INOTIFY
char buffer[1024];
assert(EventCallback);
for (;;) {
int returned = read(inotify->GetSocket(), buffer, sizeof(buffer));
assert(!(returned == 0 || (returned == -1 && errno == EINVAL)));
if (returned <= 0) {
break;
}
int current = 0;
while (current < returned) {
struct inotify_event* event = (struct inotify_event*)(buffer+current);
std::map<int, Bindable_t*>::const_iterator bindable = Files.find(event->wd);
if (bindable != Files.end()) {
if (event->mask & (IN_MODIFY | IN_CREATE | IN_DELETE | IN_MOVE)){
(*EventCallback)(bindable->second->GetBinding(), EM_CONNECTION_READ, "modified", 8);
}
if (event->mask & IN_MOVE_SELF){
(*EventCallback)(bindable->second->GetBinding(), EM_CONNECTION_READ, "moved", 5);
}
if (event->mask & IN_DELETE_SELF) {
(*EventCallback)(bindable->second->GetBinding(), EM_CONNECTION_READ, "deleted", 7);
UnwatchFile ((int)event->wd);
}
}
current += sizeof(struct inotify_event) + event->len;
}
}
#endif
}
/*************************************
EventMachine_t::_HandleKqueuePidEvent
*************************************/
#ifdef HAVE_KQUEUE
void EventMachine_t::_HandleKqueuePidEvent(struct kevent *event)
{
assert(EventCallback);
if (event->fflags & NOTE_FORK)
(*EventCallback)(Pids [(int) event->ident]->GetBinding(), EM_CONNECTION_READ, "fork", 4);
if (event->fflags & NOTE_EXIT) {
(*EventCallback)(Pids [(int) event->ident]->GetBinding(), EM_CONNECTION_READ, "exit", 4);
// stop watching the pid if it died
UnwatchPid ((int)event->ident);
}
}
#endif
/**************************************
EventMachine_t::_HandleKqueueFileEvent
***************************************/
#ifdef HAVE_KQUEUE
void EventMachine_t::_HandleKqueueFileEvent(struct kevent *event)
{
assert(EventCallback);
if (event->fflags & NOTE_WRITE)
(*EventCallback)(Files [(int) event->ident]->GetBinding(), EM_CONNECTION_READ, "modified", 8);
if (event->fflags & NOTE_RENAME)
(*EventCallback)(Files [(int) event->ident]->GetBinding(), EM_CONNECTION_READ, "moved", 5);
if (event->fflags & NOTE_DELETE) {
(*EventCallback)(Files [(int) event->ident]->GetBinding(), EM_CONNECTION_READ, "deleted", 7);
UnwatchFile ((int)event->ident);
}
}
#endif
/****************************************
EventMachine_t::_RegisterKqueueFileEvent
*****************************************/
#ifdef HAVE_KQUEUE
void EventMachine_t::_RegisterKqueueFileEvent(int fd)
{
struct kevent newevent;
int kqres;
// Setup the event with our fd and proper flags
EV_SET(&newevent, fd, EVFILT_VNODE, EV_ADD | EV_CLEAR, NOTE_DELETE | NOTE_RENAME | NOTE_WRITE, 0, 0);
// Attempt to register the event
kqres = kevent(kqfd, &newevent, 1, NULL, 0, NULL);
if (kqres == -1) {
char errbuf[200];
sprintf(errbuf, "failed to register file watch descriptor with kqueue: %s", strerror(errno));
close(fd);
throw std::runtime_error(errbuf);
}
}
#endif
/************************************
EventMachine_t::GetHeartbeatInterval
*************************************/
float EventMachine_t::GetHeartbeatInterval()
{
return ((float)HeartbeatInterval / 1000000);
}
/************************************
EventMachine_t::SetHeartbeatInterval
*************************************/
int EventMachine_t::SetHeartbeatInterval(float interval)
{
int iv = (int)(interval * 1000000);
if (iv > 0) {
HeartbeatInterval = iv;
return 1;
}
return 0;
}
//#endif // OS_UNIX