1 files changed, 242 insertions, 0 deletions
diff --git a/kqueuemplexer.cc b/kqueuemplexer.cc
new file mode 100644
index 0000000..a81487c
--- /dev/null
+++ b/kqueuemplexer.cc
@@ -0,0 +1,242 @@
+/*
+ * This file is part of PowerDNS or dnsdist.
+ * Copyright -- PowerDNS.COM B.V. and its contributors
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * In addition, for the avoidance of any doubt, permission is granted to
+ * link this program with OpenSSL and to (re)distribute the binaries
+ * produced as the result of such linking.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+#include "mplexer.hh"
+#include "sstuff.hh"
+#include <iostream>
+#include <unistd.h>
+#include "misc.hh"
+#include <sys/types.h>
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__APPLE__)
+#include <sys/event.h>
+#endif
+#include <sys/time.h>
+
+#include "namespaces.hh"
+
+class KqueueFDMultiplexer : public FDMultiplexer
+{
+public:
+  KqueueFDMultiplexer();
+  ~KqueueFDMultiplexer()
+  {
+    if (d_kqueuefd >= 0) {
+      close(d_kqueuefd);
+    }
+  }
+
+  int run(struct timeval* tv, int timeout = 500) override;
+  void getAvailableFDs(std::vector<int>& fds, int timeout) override;
+
+  void addFD(int fd, FDMultiplexer::EventKind kind) override;
+  void removeFD(int fd, FDMultiplexer::EventKind kind) override;
+
+  string getName() const override
+  {
+    return "kqueue";
+  }
+
+private:
+  int d_kqueuefd;
+  boost::shared_array<struct kevent> d_kevents;
+  static unsigned int s_maxevents; // not a hard maximum
+};
+
+unsigned int KqueueFDMultiplexer::s_maxevents = 1024;
+
+static FDMultiplexer* make()
+{
+  return new KqueueFDMultiplexer();
+}
+
+static struct KqueueRegisterOurselves
+{
+  KqueueRegisterOurselves()
+  {
+    FDMultiplexer::getMultiplexerMap().emplace(0, &make); // priority 0!
+  }
+} kQueueDoIt;
+
+KqueueFDMultiplexer::KqueueFDMultiplexer() :
+  d_kevents(new struct kevent[s_maxevents])
+{
+  d_kqueuefd = kqueue();
+  if (d_kqueuefd < 0) {
+    throw FDMultiplexerException("Setting up kqueue: " + stringerror());
+  }
+}
+
+static uint32_t convertEventKind(FDMultiplexer::EventKind kind)
+{
+  switch (kind) {
+  case FDMultiplexer::EventKind::Read:
+    return EVFILT_READ;
+  case FDMultiplexer::EventKind::Write:
+    return EVFILT_WRITE;
+  case FDMultiplexer::EventKind::Both:
+    throw std::runtime_error("Read and write events cannot be combined in one go with kqueue");
+  }
+
+  throw std::runtime_error("Unhandled event kind in the kqueue multiplexer");
+}
+
+void KqueueFDMultiplexer::addFD(int fd, FDMultiplexer::EventKind kind)
+{
+  struct kevent kqevents[2];
+  int nevents = 0;
+
+  if (kind == FDMultiplexer::EventKind::Both || kind == FDMultiplexer::EventKind::Read) {
+    EV_SET(&kqevents[nevents], fd, convertEventKind(FDMultiplexer::EventKind::Read), EV_ADD, 0, 0, 0);
+    nevents++;
+  }
+
+  if (kind == FDMultiplexer::EventKind::Both || kind == FDMultiplexer::EventKind::Write) {
+    EV_SET(&kqevents[nevents], fd, convertEventKind(FDMultiplexer::EventKind::Write), EV_ADD, 0, 0, 0);
+    nevents++;
+  }
+
+  if (kevent(d_kqueuefd, kqevents, nevents, 0, 0, 0) < 0) {
+    throw FDMultiplexerException("Adding fd to kqueue set: " + stringerror());
+  }
+}
+
+void KqueueFDMultiplexer::removeFD(int fd, FDMultiplexer::EventKind kind)
+{
+  struct kevent kqevents[2];
+  int nevents = 0;
+
+  if (kind == FDMultiplexer::EventKind::Both || kind == FDMultiplexer::EventKind::Read) {
+    EV_SET(&kqevents[nevents], fd, convertEventKind(FDMultiplexer::EventKind::Read), EV_DELETE, 0, 0, 0);
+    nevents++;
+  }
+
+  if (kind == FDMultiplexer::EventKind::Both || kind == FDMultiplexer::EventKind::Write) {
+    EV_SET(&kqevents[nevents], fd, convertEventKind(FDMultiplexer::EventKind::Write), EV_DELETE, 0, 0, 0);
+    nevents++;
+  }
+
+  if (kevent(d_kqueuefd, kqevents, nevents, 0, 0, 0) < 0) {
+    // ponder putting Callback back on the map..
+    throw FDMultiplexerException("Removing fd from kqueue set: " + stringerror());
+  }
+}
+
+void KqueueFDMultiplexer::getAvailableFDs(std::vector<int>& fds, int timeout)
+{
+  struct timespec ts;
+  ts.tv_sec = timeout / 1000;
+  ts.tv_nsec = (timeout % 1000) * 1000000;
+
+  int ret = kevent(d_kqueuefd, 0, 0, d_kevents.get(), s_maxevents, &ts);
+
+  if (ret < 0 && errno != EINTR) {
+    throw FDMultiplexerException("kqueue returned error: " + stringerror());
+  }
+
+  // we de-duplicate here, since if a descriptor is readable AND writable
+  // we will get two events
+  std::unordered_set<int> fdSet;
+  fdSet.reserve(ret);
+  for (int n = 0; n < ret; ++n) {
+    fdSet.insert(d_kevents[n].ident);
+  }
+
+  for (const auto fd : fdSet) {
+    fds.push_back(fd);
+  }
+}
+
+int KqueueFDMultiplexer::run(struct timeval* now, int timeout)
+{
+  if (d_inrun) {
+    throw FDMultiplexerException("FDMultiplexer::run() is not reentrant!\n");
+  }
+
+  struct timespec ts;
+  ts.tv_sec = timeout / 1000;
+  ts.tv_nsec = (timeout % 1000) * 1000000;
+
+  int ret = kevent(d_kqueuefd, 0, 0, d_kevents.get(), s_maxevents, &ts);
+  gettimeofday(now, nullptr); // MANDATORY!
+
+  if (ret < 0 && errno != EINTR) {
+    throw FDMultiplexerException("kqueue returned error: " + stringerror());
+  }
+
+  if (ret < 0) {
+    // nothing - thanks AB!
+    return 0;
+  }
+
+  d_inrun = true;
+
+  for (int n = 0; n < ret; ++n) {
+    if (d_kevents[n].filter == EVFILT_READ) {
+      const auto& iter = d_readCallbacks.find(d_kevents[n].ident);
+      if (iter != d_readCallbacks.end()) {
+        iter->d_callback(iter->d_fd, iter->d_parameter);
+      }
+    }
+
+    if (d_kevents[n].filter == EVFILT_WRITE) {
+      const auto& iter = d_writeCallbacks.find(d_kevents[n].ident);
+      if (iter != d_writeCallbacks.end()) {
+        iter->d_callback(iter->d_fd, iter->d_parameter);
+      }
+    }
+  }
+
+  d_inrun = false;
+  return ret;
+}
+
+#if 0
+void acceptData(int fd, boost::any& parameter)
+{
+  cout<<"Have data on fd "<<fd<<endl;
+  Socket* sock=boost::any_cast<Socket*>(parameter);
+  string packet;
+  IPEndpoint rem;
+  sock->recvFrom(packet, rem);
+  cout<<"Received "<<packet.size()<<" bytes!\n";
+}
+
+int main()
+{
+  Socket s(AF_INET, SOCK_DGRAM);
+
+  IPEndpoint loc("0.0.0.0", 2000);
+  s.bind(loc);
+
+  KqueueFDMultiplexer sfm;
+
+  sfm.addReadFD(s.getHandle(), &acceptData, &s);
+
+  for(int n=0; n < 100 ; ++n) {
+    sfm.run();
+  }
+  sfm.removeReadFD(s.getHandle());
+  sfm.removeReadFD(s.getHandle());
+}
+#endif