--- rxvt-unicode/src/iom.C	2003/11/26 10:42:34	1.4
+++ rxvt-unicode/src/iom.C	2004/12/20 16:44:31	1.27
@@ -1,6 +1,6 @@
 /*
-    iom.C -- generic I/O multiplexor
-    Copyright (C) 2003 Marc Lehmann <pcg@goof.com>
+    iom.C -- generic I/O multiplexer
+    Copyright (C) 2003, 2004 Marc Lehmann <pcg@goof.com>
  
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -17,148 +17,334 @@
     Foundation, Inc. 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
 
-#include "../config.h"
+#include "iom.h"
 
 #include <cstdio>
+#include <cstdlib>
+#include <cerrno>
 
-#include <sys/select.h>
 #include <sys/time.h>
 
-#include "iom.h"
+#include <assert.h>
 
-tstamp NOW;
-bool iom_valid;
-io_manager iom;
+#if 1 // older unices need these includes for select (2)
+# include <unistd.h>
+# include <sys/types.h>
+# include <time.h>
+#endif
 
-template<class watcher>
-void io_manager::reg (watcher *w, simplevec<watcher *> &queue)
-{
-  if (find (queue.begin (), queue.end (), w) == queue.end ())
-    queue.push_back (w);
-}
+// for IOM_SIG
+#if IOM_SIG
+# include <csignal>
+# include <fcntl.h>
+#endif
 
-template<class watcher>
-void io_manager::unreg (watcher *w, simplevec<watcher *> &queue)
-{
-  queue.erase (find (queue.begin (), queue.end (), w));
-}
+// if the BSDs would at least be marginally POSIX-compatible.. *sigh*
+// until that happens, sys/select.h must come last
+#include <sys/select.h>
+
+// TSTAMP_MAX must still fit into a positive struct timeval
+#define TSTAMP_MAX (double)(1UL<<31)
+
+#define TIMEVAL timeval
+#define TV_FRAC tv_usec
+#define TV_MULT 1000000L
 
 #if IOM_IO
-io_watcher::~io_watcher ()
-{
-  if (iom_valid)
-    iom.unreg (this);
-}
+static io_manager_vec<io_watcher>    iow;
+#endif
+#if IOM_CHECK
+static io_manager_vec<check_watcher> cw;
+#endif
+#if IOM_TIME
+static io_manager_vec<time_watcher>  tw;
+#endif
+#if IOM_IDLE
+static io_manager_vec<idle_watcher>  iw;
+#endif
+#if IOM_SIG
+static int sigpipe[2]; // signal signalling pipe
+static sigset_t sigs;
+struct sig_vec : io_manager_vec<sig_watcher> {
+  int pending;
+  sig_vec ()
+    : pending (false)
+    { }
+};
+static vector<sig_vec *> sw;
+#endif
+
+// this is a dummy time watcher to ensure that the first
+// time watcher is _always_ valid, this gets rid of a lot
+// of null-pointer-checks
+// (must come _before_ iom is being defined)
+static struct tw0 : time_watcher
+  {
+    void cb (time_watcher &w)
+    {
+      // should never get called
+      // reached end-of-time, or tstamp has a bogus definition,
+      // or compiler initialisation order broken, or something else :)
+      abort ();
+    }
 
-void io_manager::reg (io_watcher *w)
+    tw0 ()
+      : time_watcher (this, &tw0::cb)
+      { }
+  } tw0;
+
+tstamp NOW;
+
+#if IOM_TIME
+tstamp io_manager::now ()
 {
-  reg (w, iow);
+  struct timeval tv;
+
+  gettimeofday (&tv, 0);
+  return (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000.;
 }
 
-void io_manager::unreg (io_watcher *w)
+void io_manager::set_now ()
 {
-  unreg (w, iow);
+  NOW = now ();
 }
+#endif
+
+static bool iom_valid;
 
+// used for initialisation only
+static struct init {
+  init ()
+  {
+#if IOM_SIG
+    sigemptyset (&sigs);
+
+    if (pipe (sigpipe))
+      {
+        perror ("io_manager: unable to create signal pipe, aborting.");
+        abort ();
+      }
+
+    fcntl (sigpipe[0], F_SETFL, O_NONBLOCK); fcntl (sigpipe[0], F_SETFD, FD_CLOEXEC);
+    fcntl (sigpipe[1], F_SETFL, O_NONBLOCK); fcntl (sigpipe[1], F_SETFD, FD_CLOEXEC);
 #endif
 
+    iom_valid = true;
+
 #if IOM_TIME
-void time_watcher::trigger ()
-{
-  call (*this);
+    io_manager::set_now ();
 
-  iom.reg (this);
+    tw0.start (TSTAMP_MAX);
+#endif
+  }
+
+  static void required ();
+} init;
+
+void
+init::required ()
+{
+  if (!iom_valid)
+    {
+      write (2, "io_manager: early registration attempt, aborting.\n",
+                sizeof ("io_manager: early registration attempt, aborting.\n") - 1);
+      abort ();
+    }
 }
 
-time_watcher::~time_watcher ()
+template<class watcher>
+void io_manager::reg (watcher &w, io_manager_vec<watcher> &queue)
 {
-  if (iom_valid)
-    iom.unreg (this);
+  init::required ();
 
-  at = TSTAMP_CANCEL;
+  if (!w.active)
+    {
+      queue.push_back (&w);
+      w.active = queue.size ();
+    }
 }
 
-void io_manager::reg (time_watcher *w)
+template<class watcher>
+void io_manager::unreg (watcher &w, io_manager_vec<watcher> &queue)
 {
-  reg (w, tw);
+  if (!iom_valid)
+    return;
+
+  if (w.active)
+    {
+      queue [w.active - 1] = 0;
+      w.active = 0;
+    }
 }
 
-void io_manager::unreg (time_watcher *w)
+#if IOM_TIME
+void time_watcher::trigger ()
 {
-  unreg (w, tw);
+  call (*this);
+  io_manager::reg (*this);
 }
+
+void io_manager::reg   (time_watcher &w)  { io_manager::reg   (w, tw); }
+void io_manager::unreg (time_watcher &w)  { io_manager::unreg (w, tw); }
+#endif
+
+#if IOM_IO
+void io_manager::reg   (io_watcher &w)    { io_manager::reg   (w, iow); }
+void io_manager::unreg (io_watcher &w)    { io_manager::unreg (w, iow); }
 #endif
 
 #if IOM_CHECK
-check_watcher::~check_watcher ()
-{
-  if (iom_valid)
-    iom.unreg (this);
-}
+void io_manager::reg   (check_watcher &w) { io_manager::reg   (w, cw); }
+void io_manager::unreg (check_watcher &w) { io_manager::unreg (w, cw); }
+#endif
+
+#if IOM_IDLE
+void io_manager::reg   (idle_watcher &w)  { io_manager::reg   (w, iw); }
+void io_manager::unreg (idle_watcher &w)  { io_manager::unreg (w, iw); }
+#endif
 
-void io_manager::reg (check_watcher *w)
+#if IOM_SIG
+static void
+sighandler (int signum)
 {
-  reg (w, cw);
+  sw [signum - 1]->pending = true;
+
+  // we use a pipe for signal notifications, as most current
+  // OSes (Linux...) do not implement pselect correctly. ugh.
+  char ch = signum; // actual content not used
+  write (sigpipe[1], &ch, 1);
 }
 
-void io_manager::unreg (check_watcher *w)
+void io_manager::reg (sig_watcher &w)
 {
-  unreg (w, cw);
+  assert (0 < w.signum);
+
+  sw.reserve (w.signum);
+
+  while (sw.size () < w.signum) // pathetic
+    sw.push_back (0);
+
+  sig_vec *&sv = sw[w.signum - 1];
+
+  if (!sv)
+    {
+      sv = new sig_vec;
+
+      sigaddset (&sigs, w.signum);
+      sigprocmask (SIG_BLOCK, &sigs, NULL);
+
+      struct sigaction sa;
+      sa.sa_handler = sighandler;
+      sigfillset (&sa.sa_mask);
+      sa.sa_flags = SA_RESTART;
+
+      if (sigaction (w.signum, &sa, 0))
+        {
+          perror ("io_manager: error while installing signal handler, ignoring.");
+          abort ();
+        }
+
+    }
+
+  io_manager::reg (w, *sv);
 }
-#endif
 
-#if IOM_TIME
-inline void set_now (void)
+void io_manager::unreg (sig_watcher &w)
 {
-  struct timeval tv;
+  if (!w.active)
+    return;
 
-  gettimeofday (&tv, 0);
+  assert (0 < w.signum && w.signum <= sw.size ());
+  
+  io_manager::unreg (w, *sw[w.signum - 1]);
+}
 
-  NOW = (tstamp)tv.tv_sec + (tstamp)tv.tv_usec / 1000000;
-#endif
+void sig_watcher::start (int signum)
+{
+  stop ();
+  this->signum = signum;
+  io_manager::reg (*this);
 }
+#endif
 
 void io_manager::loop ()
 {
+  init::required ();
+
 #if IOM_TIME
   set_now ();
 #endif
 
   for (;;)
     {
-#if IOM_CHECK
-      for (int i = 0; i < cw.size (); ++i)
-        cw[i]->call (*cw[i]);
-#endif
 
 #if IOM_TIME
-      time_watcher *w;
+      // call pending time watchers
+      {
+        bool activity;
 
-      for (;;)
-        {
-          w = tw[0];
+        do
+          {
+            activity = false;
 
-          for (time_watcher **i = tw.begin (); i < tw.end (); ++i)
-            if ((*i)->at < w->at)
-              w = *i;
+            for (int i = tw.size (); i--; )
+              if (!tw[i])
+                tw.erase_unordered (i);
+              else if (tw[i]->at <= NOW)
+                {
+                  time_watcher &w = *tw[i];
+                  
+                  unreg (w);
+                  w.call (w);
 
-          if (w->at > NOW)
-            break;
+                  activity = true;
+                }
+          }
+        while (activity);
+      }
+#endif
+
+#if IOM_CHECK
+      // call all check watchers
+      for (int i = cw.size (); i--; )
+        if (!cw[i])
+          cw.erase_unordered (i);
+        else
+          cw[i]->call (*cw[i]);
+#endif
 
-          // call it
-          w->call (*w);
+      struct TIMEVAL *to = 0;
+      struct TIMEVAL tval;
 
-          if (w->at < 0)
-            unreg (w);
+#if IOM_IDLE
+      if (iw.size ())
+        {
+          tval.tv_sec  = 0;
+          tval.TV_FRAC = 0;
+          to = &tval;
         }
+      else
+#endif
+        {
+#if IOM_TIME
+          // find earliest active watcher
+          time_watcher *next = tw[0]; // the first time-watcher must exist at ALL times
 
-      double diff = w->at - NOW;
-      struct timeval to;
-      to.tv_sec  = (int)diff;
-      to.tv_usec = (int)((diff - to.tv_sec) * 1000000);
+          for (io_manager_vec<time_watcher>::const_iterator i = tw.end (); i-- > tw.begin (); )
+            if (*i && (*i)->at < next->at)
+              next = *i;
+
+          if (next->at > NOW && next != tw[0])
+            {
+              double diff = next->at - NOW;
+              tval.tv_sec  = (int)diff;
+              tval.TV_FRAC = (int) ((diff - tval.tv_sec) * TV_MULT);
+              to = &tval;
+            }
+        }
 #endif
 
-#if IOM_IO
+#if IOM_IO || IOM_SIG
       fd_set rfd, wfd;
 
       FD_ZERO (&rfd);
@@ -166,60 +352,104 @@
 
       int fds = 0;
 
-      for (io_watcher **w = iow.begin (); w < iow.end (); ++w)
-        {
-          if ((*w)->events & EVENT_READ ) FD_SET ((*w)->fd, &rfd);
-          if ((*w)->events & EVENT_WRITE) FD_SET ((*w)->fd, &wfd);
+# if IOM_IO
+      for (io_manager_vec<io_watcher>::const_iterator i = iow.end (); i-- > iow.begin (); )
+        if (*i)
+          {
+            if ((*i)->events & EVENT_READ ) FD_SET ((*i)->fd, &rfd);
+            if ((*i)->events & EVENT_WRITE) FD_SET ((*i)->fd, &wfd);
 
-          if ((*w)->fd > fds) fds = (*w)->fd;
-        }
+            if ((*i)->fd >= fds) fds = (*i)->fd + 1;
+          }
+# endif
+
+      if (!to && !fds) //TODO: also check idle_watchers and check_watchers?
+        break; // no events
+
+# if IOM_SIG
+      FD_SET (sigpipe[0], &rfd);
+      if (sigpipe[0] >= fds) fds = sigpipe[0] + 1;
+# endif
+
+# if IOM_SIG
+      // there is no race, as we use a pipe for signals, so select
+      // will return if a signal is caught.
+      sigprocmask (SIG_UNBLOCK, &sigs, NULL);
+# endif
+      fds = select (fds, &rfd, &wfd, NULL, to);
+# if IOM_SIG
+      sigprocmask (SIG_BLOCK, &sigs, NULL);
+# endif
 
 # if IOM_TIME
-      fds = select (fds + 1, &rfd, &wfd, 0, &to);
       set_now ();
-# else
-      fds = select (fds + 1, &rfd, &wfd, 0, 0);
 # endif
 
       if (fds > 0)
-        for (int i = 0; i < iow.size (); ++i)
-          {
-            io_watcher *w = iow[i];
-
-            short revents = w->events;
+        {
+# if IOM_SIG
+          if (FD_ISSET (sigpipe[0], &rfd))
+            {
+              char ch;
+
+              while (read (sigpipe[0], &ch, 1) > 0)
+                ;
+
+              for (vector<sig_vec *>::iterator svp = sw.end (); svp-- > sw.begin (); )
+                if (*svp && (*svp)->pending)
+                  {
+                    sig_vec &sv = **svp;
+                    for (int i = sv.size (); i--; )
+                      if (!sv[i])
+                        sv.erase_unordered (i);
+                      else
+                        sv[i]->call (*sv[i]);
+
+                    sv.pending = false;
+                  }
+            }
+# endif
 
-            if (!FD_ISSET (w->fd, &rfd)) revents &= ~EVENT_READ;
-            if (!FD_ISSET (w->fd, &wfd)) revents &= ~EVENT_WRITE;
+# if IOM_IO
+          for (int i = iow.size (); i--; )
+            if (!iow[i])
+              iow.erase_unordered (i);
+            else
+              {
+                io_watcher &w = *iow[i];
+                short revents = w.events;
+
+                if (!FD_ISSET (w.fd, &rfd)) revents &= ~EVENT_READ;
+                if (!FD_ISSET (w.fd, &wfd)) revents &= ~EVENT_WRITE;
+
+                if (revents)
+                  w.call (w, revents);
+              }
+#endif
+        }
+      else if (fds < 0 && errno != EINTR)
+        {
+          perror ("io_manager: fatal error while waiting for I/O or time event, aborting.");
+          abort ();
+        }
+#if IOM_IDLE
+      else
+        for (int i = iw.size (); i--; )
+          if (!iw[i])
+            iw.erase_unordered (i);
+          else
+            iw[i]->call (*iw[i]);
+#endif
 
-            if (revents)
-              w->call (*w, revents);
-          }
-    }
 #elif IOM_TIME
+      if (!to)
+        break;
+
       select (0, 0, 0, 0, &to);
       set_now ();
+#else
+      break;
 #endif
-}
-
-void io_manager::idle_cb (time_watcher &w)
-{
-  w.at = NOW + 1000000000;
-}
-
-io_manager::io_manager ()
-{
-  set_now ();
-
-  iom_valid = true;
-
-#if IOM_TIME
-  idle = new time_watcher (this, &io_manager::idle_cb);
-  idle->start (0);
-#endif
-}
-
-io_manager::~io_manager ()
-{
-  iom_valid = false;
+    }
 }