[ViewVC] Diff of: cvs/libev/ev.c

Comparing libev/ev.c (file contents):
Revision 1.136 by root, Sat Nov 24 07:14:26 2007 UTC vs.
Revision 1.170 by root, Sat Dec 8 22:11:14 2007 UTC

 #  else
 #   define EV_USE_PORT 0
 #  endif
 # endif
+# ifndef EV_USE_INOTIFY
+#  if HAVE_INOTIFY_INIT && HAVE_SYS_INOTIFY_H
+#   define EV_USE_INOTIFY 1
+#  else
+#   define EV_USE_INOTIFY 0
+#  endif
+# endif
 #endif
 #include <math.h>
 #include <stdlib.h>
 #include <fcntl.h>
 #include <sys/types.h>
 #include <time.h>
 #include <signal.h>
+#ifdef EV_H
+# include EV_H
+#else
+# include "ev.h"
+#endif
 #ifndef _WIN32
-# include <unistd.h>
 # include <sys/time.h>
 # include <sys/wait.h>
+# include <unistd.h>
 #else
 # define WIN32_LEAN_AND_MEAN
 # include <windows.h>
 # ifndef EV_SELECT_IS_WINSOCKET
 #  define EV_SELECT_IS_WINSOCKET 1
 #ifndef EV_USE_PORT
 # define EV_USE_PORT 0
 #endif
+#ifndef EV_USE_INOTIFY
+# define EV_USE_INOTIFY 0
+#endif
+#ifndef EV_PID_HASHSIZE
+# if EV_MINIMAL
+#  define EV_PID_HASHSIZE 1
+# else
+#  define EV_PID_HASHSIZE 16
+# endif
+#endif
+#ifndef EV_INOTIFY_HASHSIZE
+# if EV_MINIMAL
+#  define EV_INOTIFY_HASHSIZE 1
+# else
+#  define EV_INOTIFY_HASHSIZE 16
+# endif
+#endif
 /**/
 #ifndef CLOCK_MONOTONIC
 # undef EV_USE_MONOTONIC
 # define EV_USE_MONOTONIC 0
 #if EV_SELECT_IS_WINSOCKET
 # include <winsock.h>
 #endif
+#if !EV_STAT_ENABLE
+# define EV_USE_INOTIFY 0
+#endif
+#if EV_USE_INOTIFY
+# include <sys/inotify.h>
+#endif
 /**/
 #define MIN_TIMEJUMP  1. /* minimum timejump that gets detected (if monotonic clock available) */
 #define MAX_BLOCKTIME 59.743 /* never wait longer than this time (to detect time jumps) */
-#define PID_HASHSIZE  16 /* size of pid hash table, must be power of two */
 /*#define CLEANUP_INTERVAL (MAX_BLOCKTIME * 5.) /* how often to try to free memory and re-check fds */
-#ifdef EV_H
-# include EV_H
-#else
-# include "ev.h"
-#endif
 #if __GNUC__ >= 3
 # define expect(expr,value)         __builtin_expect ((expr),(value))
-# define inline                     static inline
+# define noinline                   __attribute__ ((noinline))
 #else
 # define expect(expr,value)         (expr)
-# define inline                     static
+# define noinline
+# if __STDC_VERSION__ < 199901L
+#  define inline
+# endif
 #endif
 #define expect_false(expr) expect ((expr) != 0, 0)
 #define expect_true(expr)  expect ((expr) != 0, 1)
+#define inline_size        static inline
+#if EV_MINIMAL
+# define inline_speed      static noinline
+#else
+# define inline_speed      static inline
+#endif
 #define NUMPRI    (EV_MAXPRI - EV_MINPRI + 1)
-#define ABSPRI(w) ((w)->priority - EV_MINPRI)
+#define ABSPRI(w) (((W)w)->priority - EV_MINPRI)
-#define EMPTY0      /* required for microsofts broken pseudo-c compiler */
+#define EMPTY       /* required for microsofts broken pseudo-c compiler */
 #define EMPTY2(a,b) /* used to suppress some warnings */
 typedef ev_watcher *W;
 typedef ev_watcher_list *WL;
 typedef ev_watcher_time *WT;
 /*****************************************************************************/
 static void (*syserr_cb)(const char *msg);
+void
-void ev_set_syserr_cb (void (*cb)(const char *msg))
+ev_set_syserr_cb (void (*cb)(const char *msg))
 {
   syserr_cb = cb;
 }
-static void
+static void noinline
 syserr (const char *msg)
 {
   if (!msg)
     msg = "(libev) system error";
     }
 }
 static void *(*alloc)(void *ptr, long size);
+void
-void ev_set_allocator (void *(*cb)(void *ptr, long size))
+ev_set_allocator (void *(*cb)(void *ptr, long size))
 {
   alloc = cb;
 }
-static void *
+inline_speed void *
 ev_realloc (void *ptr, long size)
 {
   ptr = alloc ? alloc (ptr, size) : realloc (ptr, size);
   if (!ptr && size)
 typedef struct
 {
   W w;
   int events;
 } ANPENDING;
+#if EV_USE_INOTIFY
+typedef struct
+{
+  WL head;
+} ANFS;
+#endif
 #if EV_MULTIPLICITY
   struct ev_loop
   {
   gettimeofday (&tv, 0);
   return tv.tv_sec + tv.tv_usec * 1e-6;
 #endif
 }
-inline ev_tstamp
+ev_tstamp inline_size
 get_clock (void)
 {
 #if EV_USE_MONOTONIC
   if (expect_true (have_monotonic))
     {
 {
   return ev_rt_now;
 }
 #endif
-#define array_roundsize(type,n) (((n) | 4) & ~3)
+int inline_size
+array_nextsize (int elem, int cur, int cnt)
+{
+  int ncur = cur + 1;
+  do
+    ncur <<= 1;
+  while (cnt > ncur);
+  /* if size > 4096, round to 4096 - 4 * longs to accomodate malloc overhead */
+  if (elem * ncur > 4096)
+    {
+      ncur *= elem;
+      ncur = (ncur + elem + 4095 + sizeof (void *) * 4) & ~4095;
+      ncur = ncur - sizeof (void *) * 4;
+      ncur /= elem;
+    }
+  return ncur;
+}
+inline_speed void *
+array_realloc (int elem, void *base, int *cur, int cnt)
+{
+  *cur = array_nextsize (elem, *cur, cnt);
+  return ev_realloc (base, elem * *cur);
+}
 #define array_needsize(type,base,cur,cnt,init)			\
-  if (expect_false ((cnt) > cur))				\
+  if (expect_false ((cnt) > (cur)))				\
     {								\
-      int newcnt = cur;						\
+      int ocur_ = (cur);					\
-      do							\
+      (base) = (type *)array_realloc				\
-        {							\
+         (sizeof (type), (base), &(cur), (cnt));		\
-          newcnt = array_roundsize (type, newcnt << 1);		\
+      init ((base) + (ocur_), (cur) - ocur_);			\
-        }							\
-      while ((cnt) > newcnt);					\
-      								\
-      base = (type *)ev_realloc (base, sizeof (type) * (newcnt));\
-      init (base + cur, newcnt - cur);				\
-      cur = newcnt;						\
     }
+#if 0
 #define array_slim(type,stem)					\
   if (stem ## max < array_roundsize (stem ## cnt >> 2))		\
     {								\
       stem ## max = array_roundsize (stem ## cnt >> 1);		\
       base = (type *)ev_realloc (base, sizeof (type) * (stem ## max));\
       fprintf (stderr, "slimmed down " # stem " to %d\n", stem ## max);/*D*/\
     }
+#endif
 #define array_free(stem, idx) \
   ev_free (stem ## s idx); stem ## cnt idx = stem ## max idx = 0;
 /*****************************************************************************/
-static void
+void noinline
-anfds_init (ANFD *base, int count)
-{
-  while (count--)
-    {
-      base->head   = 0;
-      base->events = EV_NONE;
-      base->reify  = 0;
-      ++base;
-    }
-}
-void
 ev_feed_event (EV_P_ void *w, int revents)
 {
   W w_ = (W)w;
   if (expect_false (w_->pending))
   array_needsize (ANPENDING, pendings [ABSPRI (w_)], pendingmax [ABSPRI (w_)], pendingcnt [ABSPRI (w_)], EMPTY2);
   pendings [ABSPRI (w_)][w_->pending - 1].w      = w_;
   pendings [ABSPRI (w_)][w_->pending - 1].events = revents;
 }
-static void
+void inline_size
 queue_events (EV_P_ W *events, int eventcnt, int type)
 {
   int i;
   for (i = 0; i < eventcnt; ++i)
     ev_feed_event (EV_A_ events [i], type);
 }
-inline void
+/*****************************************************************************/
+void inline_size
+anfds_init (ANFD *base, int count)
+{
+  while (count--)
+    {
+      base->head   = 0;
+      base->events = EV_NONE;
+      base->reify  = 0;
+      ++base;
+    }
+}
+void inline_speed
 fd_event (EV_P_ int fd, int revents)
 {
   ANFD *anfd = anfds + fd;
   ev_io *w;
 }
 void
 ev_feed_fd_event (EV_P_ int fd, int revents)
 {
+  if (fd >= 0 && fd < anfdmax)
-  fd_event (EV_A_ fd, revents);
+    fd_event (EV_A_ fd, revents);
 }
-/*****************************************************************************/
+void inline_size
-inline void
 fd_reify (EV_P)
 {
   int i;
   for (i = 0; i < fdchangecnt; ++i)
     }
   fdchangecnt = 0;
 }
-static void
+void inline_size
 fd_change (EV_P_ int fd)
 {
   if (expect_false (anfds [fd].reify))
     return;
   ++fdchangecnt;
   array_needsize (int, fdchanges, fdchangemax, fdchangecnt, EMPTY2);
   fdchanges [fdchangecnt - 1] = fd;
 }
-static void
+void inline_speed
 fd_kill (EV_P_ int fd)
 {
   ev_io *w;
   while ((w = (ev_io *)anfds [fd].head))
       ev_io_stop (EV_A_ w);
       ev_feed_event (EV_A_ (W)w, EV_ERROR | EV_READ | EV_WRITE);
     }
 }
-inline int
+int inline_size
 fd_valid (int fd)
 {
 #ifdef _WIN32
   return _get_osfhandle (fd) != -1;
 #else
   return fcntl (fd, F_GETFD) != -1;
 #endif
 }
 /* called on EBADF to verify fds */
-static void
+static void noinline
 fd_ebadf (EV_P)
 {
   int fd;
   for (fd = 0; fd < anfdmax; ++fd)
       if (!fd_valid (fd) == -1 && errno == EBADF)
         fd_kill (EV_A_ fd);
 }
 /* called on ENOMEM in select/poll to kill some fds and retry */
-static void
+static void noinline
 fd_enomem (EV_P)
 {
   int fd;
   for (fd = anfdmax; fd--; )
         return;
       }
 }
 /* usually called after fork if backend needs to re-arm all fds from scratch */
-static void
+static void noinline
 fd_rearm_all (EV_P)
 {
   int fd;
-  /* this should be highly optimised to not do anything but set a flag */
   for (fd = 0; fd < anfdmax; ++fd)
     if (anfds [fd].events)
       {
         anfds [fd].events = 0;
         fd_change (EV_A_ fd);
       }
 }
 /*****************************************************************************/
-static void
+void inline_speed
 upheap (WT *heap, int k)
 {
   WT w = heap [k];
   while (k && heap [k >> 1]->at > w->at)
   heap [k] = w;
   ((W)heap [k])->active = k + 1;
 }
-static void
+void inline_speed
 downheap (WT *heap, int N, int k)
 {
   WT w = heap [k];
   while (k < (N >> 1))
   heap [k] = w;
   ((W)heap [k])->active = k + 1;
 }
-inline void
+void inline_size
 adjustheap (WT *heap, int N, int k)
 {
   upheap (heap, k);
   downheap (heap, N, k);
 }
 static int sigpipe [2];
 static sig_atomic_t volatile gotsig;
 static ev_io sigev;
-static void
+void inline_size
 signals_init (ANSIG *base, int count)
 {
   while (count--)
     {
       base->head   = 0;
       write (sigpipe [1], &signum, 1);
       errno = old_errno;
     }
 }
-void
+void noinline
 ev_feed_signal_event (EV_P_ int signum)
 {
   WL w;
 #if EV_MULTIPLICITY
   for (signum = signalmax; signum--; )
     if (signals [signum].gotsig)
       ev_feed_signal_event (EV_A_ signum + 1);
 }
-static void
+void inline_size
 fd_intern (int fd)
 {
 #ifdef _WIN32
   int arg = 1;
   ioctlsocket (_get_osfhandle (fd), FIONBIO, &arg);
   fcntl (fd, F_SETFD, FD_CLOEXEC);
   fcntl (fd, F_SETFL, O_NONBLOCK);
 #endif
 }
-static void
+static void noinline
 siginit (EV_P)
 {
   fd_intern (sigpipe [0]);
   fd_intern (sigpipe [1]);
   ev_unref (EV_A); /* child watcher should not keep loop alive */
 }
 /*****************************************************************************/
-static ev_child *childs [PID_HASHSIZE];
+static ev_child *childs [EV_PID_HASHSIZE];
 #ifndef _WIN32
 static ev_signal childev;
+void inline_speed
+child_reap (EV_P_ ev_signal *sw, int chain, int pid, int status)
+{
+  ev_child *w;
+  for (w = (ev_child *)childs [chain & (EV_PID_HASHSIZE - 1)]; w; w = (ev_child *)((WL)w)->next)
+    if (w->pid == pid || !w->pid)
+      {
+        ev_set_priority (w, ev_priority (sw)); /* need to do it *now* */
+        w->rpid    = pid;
+        w->rstatus = status;
+        ev_feed_event (EV_A_ (W)w, EV_CHILD);
+      }
+}
 #ifndef WCONTINUED
 # define WCONTINUED 0
 #endif
 static void
-child_reap (EV_P_ ev_signal *sw, int chain, int pid, int status)
-{
-  ev_child *w;
-  for (w = (ev_child *)childs [chain & (PID_HASHSIZE - 1)]; w; w = (ev_child *)((WL)w)->next)
-    if (w->pid == pid || !w->pid)
-      {
-        ev_priority (w) = ev_priority (sw); /* need to do it *now* */
-        w->rpid         = pid;
-        w->rstatus      = status;
-        ev_feed_event (EV_A_ (W)w, EV_CHILD);
-      }
-}
-static void
 childcb (EV_P_ ev_signal *sw, int revents)
 {
   int pid, status;
+  /* some systems define WCONTINUED but then fail to support it (linux 2.4) */
-  if (0 < (pid = waitpid (-1, &status, WNOHANG | WUNTRACED | WCONTINUED)))
+  if (0 >= (pid = waitpid (-1, &status, WNOHANG | WUNTRACED | WCONTINUED)))
-    {
+    if (!WCONTINUED
+        || errno != EINVAL
+        || 0 >= (pid = waitpid (-1, &status, WNOHANG | WUNTRACED)))
+      return;
-      /* make sure we are called again until all childs have been reaped */
+  /* make sure we are called again until all childs have been reaped */
-      /* we need to do it this way so that the callback gets called before we continue */
+  /* we need to do it this way so that the callback gets called before we continue */
-      ev_feed_event (EV_A_ (W)sw, EV_SIGNAL);
+  ev_feed_event (EV_A_ (W)sw, EV_SIGNAL);
-      child_reap (EV_A_ sw, pid, pid, status);
+  child_reap (EV_A_ sw, pid, pid, status);
+  if (EV_PID_HASHSIZE > 1)
-      child_reap (EV_A_ sw,   0, pid, status); /* this might trigger a watcher twice, but feed_event catches that */
+    child_reap (EV_A_ sw, 0, pid, status); /* this might trigger a watcher twice, but feed_event catches that */
-    }
 }
 #endif
 /*****************************************************************************/
 {
   return EV_VERSION_MINOR;
 }
 /* return true if we are running with elevated privileges and should ignore env variables */
-static int
+int inline_size
 enable_secure (void)
 {
 #ifdef _WIN32
   return 0;
 #else
 ev_backend (EV_P)
 {
   return backend;
 }
-static void
+unsigned int
+ev_loop_count (EV_P)
+{
+  return loop_count;
+}
+static void noinline
 loop_init (EV_P_ unsigned int flags)
 {
   if (!backend)
     {
 #if EV_USE_MONOTONIC
       ev_rt_now = ev_time ();
       mn_now    = get_clock ();
       now_floor = mn_now;
       rtmn_diff = ev_rt_now - mn_now;
+      /* pid check not overridable via env */
+#ifndef _WIN32
+      if (flags & EVFLAG_FORKCHECK)
+        curpid = getpid ();
+#endif
       if (!(flags & EVFLAG_NOENV)
           && !enable_secure ()
           && getenv ("LIBEV_FLAGS"))
         flags = atoi (getenv ("LIBEV_FLAGS"));
       if (!(flags & 0x0000ffffUL))
         flags |= ev_recommended_backends ();
       backend = 0;
+      backend_fd = -1;
+#if EV_USE_INOTIFY
+      fs_fd = -2;
+#endif
 #if EV_USE_PORT
       if (!backend && (flags & EVBACKEND_PORT  )) backend = port_init   (EV_A_ flags);
 #endif
 #if EV_USE_KQUEUE
       if (!backend && (flags & EVBACKEND_KQUEUE)) backend = kqueue_init (EV_A_ flags);
       ev_init (&sigev, sigcb);
       ev_set_priority (&sigev, EV_MAXPRI);
     }
 }
-static void
+static void noinline
 loop_destroy (EV_P)
 {
   int i;
+#if EV_USE_INOTIFY
+  if (fs_fd >= 0)
+    close (fs_fd);
+#endif
+  if (backend_fd >= 0)
+    close (backend_fd);
 #if EV_USE_PORT
   if (backend == EVBACKEND_PORT  ) port_destroy   (EV_A);
 #endif
 #if EV_USE_KQUEUE
 #if EV_USE_SELECT
   if (backend == EVBACKEND_SELECT) select_destroy (EV_A);
 #endif
   for (i = NUMPRI; i--; )
+    {
-    array_free (pending, [i]);
+      array_free (pending, [i]);
+#if EV_IDLE_ENABLE
+      array_free (idle, [i]);
+#endif
+    }
   /* have to use the microsoft-never-gets-it-right macro */
-  array_free (fdchange, EMPTY0);
+  array_free (fdchange, EMPTY);
-  array_free (timer, EMPTY0);
+  array_free (timer, EMPTY);
-#if EV_PERIODICS
+#if EV_PERIODIC_ENABLE
-  array_free (periodic, EMPTY0);
+  array_free (periodic, EMPTY);
 #endif
-  array_free (idle, EMPTY0);
-  array_free (prepare, EMPTY0);
+  array_free (prepare, EMPTY);
-  array_free (check, EMPTY0);
+  array_free (check, EMPTY);
   backend = 0;
 }
-static void
+void inline_size infy_fork (EV_P);
+void inline_size
 loop_fork (EV_P)
 {
 #if EV_USE_PORT
   if (backend == EVBACKEND_PORT  ) port_fork   (EV_A);
 #endif
 #if EV_USE_KQUEUE
   if (backend == EVBACKEND_KQUEUE) kqueue_fork (EV_A);
 #endif
 #if EV_USE_EPOLL
   if (backend == EVBACKEND_EPOLL ) epoll_fork  (EV_A);
+#endif
+#if EV_USE_INOTIFY
+  infy_fork (EV_A);
 #endif
   if (ev_is_active (&sigev))
     {
       /* default loop */
     postfork = 1;
 }
 /*****************************************************************************/
-static int
+void
-any_pending (EV_P)
+ev_invoke (EV_P_ void *w, int revents)
 {
-  int pri;
+  EV_CB_INVOKE ((W)w, revents);
-  for (pri = NUMPRI; pri--; )
-    if (pendingcnt [pri])
-      return 1;
-  return 0;
 }
-inline void
+void inline_speed
 call_pending (EV_P)
 {
   int pri;
   for (pri = NUMPRI; pri--; )
       {
         ANPENDING *p = pendings [pri] + --pendingcnt [pri];
         if (expect_true (p->w))
           {
+            /*assert (("non-pending watcher on pending list", p->w->pending));*/
             p->w->pending = 0;
             EV_CB_INVOKE (p->w, p->events);
           }
       }
 }
-inline void
+void inline_size
 timers_reify (EV_P)
 {
   while (timercnt && ((WT)timers [0])->at <= mn_now)
     {
       ev_timer *w = timers [0];
-      assert (("inactive timer on timer heap detected", ev_is_active (w)));
+      /*assert (("inactive timer on timer heap detected", ev_is_active (w)));*/
       /* first reschedule or stop timer */
       if (w->repeat)
         {
           assert (("negative ev_timer repeat value found while processing timers", w->repeat > 0.));
       ev_feed_event (EV_A_ (W)w, EV_TIMEOUT);
     }
 }
-#if EV_PERIODICS
+#if EV_PERIODIC_ENABLE
-inline void
+void inline_size
 periodics_reify (EV_P)
 {
   while (periodiccnt && ((WT)periodics [0])->at <= ev_rt_now)
     {
       ev_periodic *w = periodics [0];
-      assert (("inactive timer on periodic heap detected", ev_is_active (w)));
+      /*assert (("inactive timer on periodic heap detected", ev_is_active (w)));*/
       /* first reschedule or stop timer */
       if (w->reschedule_cb)
         {
           ((WT)w)->at = w->reschedule_cb (w, ev_rt_now + 0.0001);
       ev_feed_event (EV_A_ (W)w, EV_PERIODIC);
     }
 }
-static void
+static void noinline
 periodics_reschedule (EV_P)
 {
   int i;
   /* adjust periodics after time jump */
   for (i = periodiccnt >> 1; i--; )
     downheap ((WT *)periodics, periodiccnt, i);
 }
 #endif
-inline int
+#if EV_IDLE_ENABLE
+void inline_size
+idle_reify (EV_P)
+{
+  if (expect_false (idleall))
+    {
+      int pri;
+      for (pri = NUMPRI; pri--; )
+        {
+          if (pendingcnt [pri])
+            break;
+          if (idlecnt [pri])
+            {
+              queue_events (EV_A_ (W *)idles [pri], idlecnt [pri], EV_IDLE);
+              break;
+            }
+        }
+    }
+}
+#endif
+int inline_size
 time_update_monotonic (EV_P)
 {
   mn_now = get_clock ();
   if (expect_true (mn_now - now_floor < MIN_TIMEJUMP * .5))
       ev_rt_now = ev_time ();
       return 1;
     }
 }
-inline void
+void inline_size
 time_update (EV_P)
 {
   int i;
 #if EV_USE_MONOTONIC
     {
       if (time_update_monotonic (EV_A))
         {
           ev_tstamp odiff = rtmn_diff;
-          for (i = 4; --i; ) /* loop a few times, before making important decisions */
+          /* loop a few times, before making important decisions.
+           * on the choice of "4": one iteration isn't enough,
+           * in case we get preempted during the calls to
+           * ev_time and get_clock. a second call is almost guaranteed
+           * to succeed in that case, though. and looping a few more times
+           * doesn't hurt either as we only do this on time-jumps or
+           * in the unlikely event of having been preempted here.
+           */
+          for (i = 4; --i; )
             {
               rtmn_diff = ev_rt_now - mn_now;
               if (fabs (odiff - rtmn_diff) < MIN_TIMEJUMP)
                 return; /* all is well */
               ev_rt_now = ev_time ();
               mn_now    = get_clock ();
               now_floor = mn_now;
             }
-# if EV_PERIODICS
+# if EV_PERIODIC_ENABLE
           periodics_reschedule (EV_A);
 # endif
           /* no timer adjustment, as the monotonic clock doesn't jump */
           /* timers_reschedule (EV_A_ rtmn_diff - odiff) */
         }
     {
       ev_rt_now = ev_time ();
       if (expect_false (mn_now > ev_rt_now || mn_now < ev_rt_now - MAX_BLOCKTIME - MIN_TIMEJUMP))
         {
-#if EV_PERIODICS
+#if EV_PERIODIC_ENABLE
           periodics_reschedule (EV_A);
 #endif
-          /* adjust timers. this is easy, as the offset is the same for all */
+          /* adjust timers. this is easy, as the offset is the same for all of them */
           for (i = 0; i < timercnt; ++i)
             ((WT)timers [i])->at += ev_rt_now - mn_now;
         }
       mn_now = ev_rt_now;
 {
   loop_done = flags & (EVLOOP_ONESHOT | EVLOOP_NONBLOCK)
             ? EVUNLOOP_ONE
             : EVUNLOOP_CANCEL;
-  while (activecnt)
+  call_pending (EV_A); /* in case we recurse, ensure ordering stays nice and clean */
+  do
     {
+#ifndef _WIN32
+      if (expect_false (curpid)) /* penalise the forking check even more */
+        if (expect_false (getpid () != curpid))
+          {
+            curpid = getpid ();
+            postfork = 1;
+          }
+#endif
+#if EV_FORK_ENABLE
+      /* we might have forked, so queue fork handlers */
+      if (expect_false (postfork))
+        if (forkcnt)
+          {
+            queue_events (EV_A_ (W *)forks, forkcnt, EV_FORK);
+            call_pending (EV_A);
+          }
+#endif
-      /* queue check watchers (and execute them) */
+      /* queue prepare watchers (and execute them) */
       if (expect_false (preparecnt))
         {
           queue_events (EV_A_ (W *)prepares, preparecnt, EV_PREPARE);
           call_pending (EV_A);
         }
+      if (expect_false (!activecnt))
+        break;
       /* we might have forked, so reify kernel state if necessary */
       if (expect_false (postfork))
         loop_fork (EV_A);
       /* update fd-related kernel structures */
       fd_reify (EV_A);
       /* calculate blocking time */
       {
-        double block;
+        ev_tstamp block;
-        if (flags & EVLOOP_NONBLOCK || idlecnt)
+        if (expect_false (flags & EVLOOP_NONBLOCK || idleall || !activecnt))
           block = 0.; /* do not block at all */
         else
           {
             /* update time to cancel out callback processing overhead */
 #if EV_USE_MONOTONIC
               {
                 ev_tstamp to = ((WT)timers [0])->at - mn_now + backend_fudge;
                 if (block > to) block = to;
               }
-#if EV_PERIODICS
+#if EV_PERIODIC_ENABLE
             if (periodiccnt)
               {
                 ev_tstamp to = ((WT)periodics [0])->at - ev_rt_now + backend_fudge;
                 if (block > to) block = to;
               }
 #endif
             if (expect_false (block < 0.)) block = 0.;
           }
+        ++loop_count;
         backend_poll (EV_A_ block);
       }
       /* update ev_rt_now, do magic */
       time_update (EV_A);
       /* queue pending timers and reschedule them */
       timers_reify (EV_A); /* relative timers called last */
-#if EV_PERIODICS
+#if EV_PERIODIC_ENABLE
       periodics_reify (EV_A); /* absolute timers called first */
 #endif
+#if EV_IDLE_ENABLE
-      /* queue idle watchers unless io or timers are pending */
+      /* queue idle watchers unless other events are pending */
-      if (idlecnt && !any_pending (EV_A))
+      idle_reify (EV_A);
-        queue_events (EV_A_ (W *)idles, idlecnt, EV_IDLE);
+#endif
       /* queue check watchers, to be executed first */
       if (expect_false (checkcnt))
         queue_events (EV_A_ (W *)checks, checkcnt, EV_CHECK);
       call_pending (EV_A);
-      if (expect_false (loop_done))
-        break;
     }
+  while (expect_true (activecnt && !loop_done));
   if (loop_done == EVUNLOOP_ONE)
     loop_done = EVUNLOOP_CANCEL;
 }
   loop_done = how;
 }
 /*****************************************************************************/
-inline void
+void inline_size
 wlist_add (WL *head, WL elem)
 {
   elem->next = *head;
   *head = elem;
 }
-inline void
+void inline_size
 wlist_del (WL *head, WL elem)
 {
   while (*head)
     {
       if (*head == elem)
       head = &(*head)->next;
     }
 }
-inline void
+void inline_speed
-ev_clear_pending (EV_P_ W w)
+clear_pending (EV_P_ W w)
 {
   if (w->pending)
     {
       pendings [ABSPRI (w)][w->pending - 1].w = 0;
       w->pending = 0;
     }
 }
-inline void
+int
+ev_clear_pending (EV_P_ void *w)
+{
+  W w_ = (W)w;
+  int pending = w_->pending;
+  if (!pending)
+    return 0;
+  w_->pending = 0;
+  ANPENDING *p = pendings [ABSPRI (w_)] + pending - 1;
+  p->w = 0;
+  return p->events;
+}
+void inline_size
+pri_adjust (EV_P_ W w)
+{
+  int pri = w->priority;
+  pri = pri < EV_MINPRI ? EV_MINPRI : pri;
+  pri = pri > EV_MAXPRI ? EV_MAXPRI : pri;
+  w->priority = pri;
+}
+void inline_speed
 ev_start (EV_P_ W w, int active)
 {
-  if (w->priority < EV_MINPRI) w->priority = EV_MINPRI;
+  pri_adjust (EV_A_ w);
-  if (w->priority > EV_MAXPRI) w->priority = EV_MAXPRI;
   w->active = active;
   ev_ref (EV_A);
 }
-inline void
+void inline_size
 ev_stop (EV_P_ W w)
 {
   ev_unref (EV_A);
   w->active = 0;
 }
 }
 void
 ev_io_stop (EV_P_ ev_io *w)
 {
-  ev_clear_pending (EV_A_ (W)w);
+  clear_pending (EV_A_ (W)w);
   if (expect_false (!ev_is_active (w)))
     return;
   assert (("ev_io_start called with illegal fd (must stay constant after start!)", w->fd >= 0 && w->fd < anfdmax));
   ev_start (EV_A_ (W)w, ++timercnt);
   array_needsize (ev_timer *, timers, timermax, timercnt, EMPTY2);
   timers [timercnt - 1] = w;
   upheap ((WT *)timers, timercnt - 1);
+  /*assert (("internal timer heap corruption", timers [((W)w)->active - 1] == w));*/
+}
+void
+ev_timer_stop (EV_P_ ev_timer *w)
+{
+  clear_pending (EV_A_ (W)w);
+  if (expect_false (!ev_is_active (w)))
+    return;
   assert (("internal timer heap corruption", timers [((W)w)->active - 1] == w));
-}
-void
+  {
-ev_timer_stop (EV_P_ ev_timer *w)
+    int active = ((W)w)->active;
-{
-  ev_clear_pending (EV_A_ (W)w);
-  if (expect_false (!ev_is_active (w)))
-    return;
-  assert (("internal timer heap corruption", timers [((W)w)->active - 1] == w));
-  if (expect_true (((W)w)->active < timercnt--))
+    if (expect_true (--active < --timercnt))
-    {
+      {
-      timers [((W)w)->active - 1] = timers [timercnt];
+        timers [active] = timers [timercnt];
-      adjustheap ((WT *)timers, timercnt, ((W)w)->active - 1);
+        adjustheap ((WT *)timers, timercnt, active);
-    }
+      }
+  }
   ((WT)w)->at -= mn_now;
   ev_stop (EV_A_ (W)w);
 }
       w->at = w->repeat;
       ev_timer_start (EV_A_ w);
     }
 }
-#if EV_PERIODICS
+#if EV_PERIODIC_ENABLE
 void
 ev_periodic_start (EV_P_ ev_periodic *w)
 {
   if (expect_false (ev_is_active (w)))
     return;
   ev_start (EV_A_ (W)w, ++periodiccnt);
   array_needsize (ev_periodic *, periodics, periodicmax, periodiccnt, EMPTY2);
   periodics [periodiccnt - 1] = w;
   upheap ((WT *)periodics, periodiccnt - 1);
+  /*assert (("internal periodic heap corruption", periodics [((W)w)->active - 1] == w));*/
+}
+void
+ev_periodic_stop (EV_P_ ev_periodic *w)
+{
+  clear_pending (EV_A_ (W)w);
+  if (expect_false (!ev_is_active (w)))
+    return;
   assert (("internal periodic heap corruption", periodics [((W)w)->active - 1] == w));
-}
-void
+  {
-ev_periodic_stop (EV_P_ ev_periodic *w)
+    int active = ((W)w)->active;
-{
-  ev_clear_pending (EV_A_ (W)w);
-  if (expect_false (!ev_is_active (w)))
-    return;
-  assert (("internal periodic heap corruption", periodics [((W)w)->active - 1] == w));
-  if (expect_true (((W)w)->active < periodiccnt--))
+    if (expect_true (--active < --periodiccnt))
-    {
+      {
-      periodics [((W)w)->active - 1] = periodics [periodiccnt];
+        periodics [active] = periodics [periodiccnt];
-      adjustheap ((WT *)periodics, periodiccnt, ((W)w)->active - 1);
+        adjustheap ((WT *)periodics, periodiccnt, active);
-    }
+      }
+  }
   ev_stop (EV_A_ (W)w);
 }
 void
   /* TODO: use adjustheap and recalculation */
   ev_periodic_stop (EV_A_ w);
   ev_periodic_start (EV_A_ w);
 }
 #endif
-void
-ev_idle_start (EV_P_ ev_idle *w)
-{
-  if (expect_false (ev_is_active (w)))
-    return;
-  ev_start (EV_A_ (W)w, ++idlecnt);
-  array_needsize (ev_idle *, idles, idlemax, idlecnt, EMPTY2);
-  idles [idlecnt - 1] = w;
-}
-void
-ev_idle_stop (EV_P_ ev_idle *w)
-{
-  ev_clear_pending (EV_A_ (W)w);
-  if (expect_false (!ev_is_active (w)))
-    return;
-  idles [((W)w)->active - 1] = idles [--idlecnt];
-  ev_stop (EV_A_ (W)w);
-}
-void
-ev_prepare_start (EV_P_ ev_prepare *w)
-{
-  if (expect_false (ev_is_active (w)))
-    return;
-  ev_start (EV_A_ (W)w, ++preparecnt);
-  array_needsize (ev_prepare *, prepares, preparemax, preparecnt, EMPTY2);
-  prepares [preparecnt - 1] = w;
-}
-void
-ev_prepare_stop (EV_P_ ev_prepare *w)
-{
-  ev_clear_pending (EV_A_ (W)w);
-  if (expect_false (!ev_is_active (w)))
-    return;
-  prepares [((W)w)->active - 1] = prepares [--preparecnt];
-  ev_stop (EV_A_ (W)w);
-}
-void
-ev_check_start (EV_P_ ev_check *w)
-{
-  if (expect_false (ev_is_active (w)))
-    return;
-  ev_start (EV_A_ (W)w, ++checkcnt);
-  array_needsize (ev_check *, checks, checkmax, checkcnt, EMPTY2);
-  checks [checkcnt - 1] = w;
-}
-void
-ev_check_stop (EV_P_ ev_check *w)
-{
-  ev_clear_pending (EV_A_ (W)w);
-  if (expect_false (!ev_is_active (w)))
-    return;
-  checks [((W)w)->active - 1] = checks [--checkcnt];
-  ev_stop (EV_A_ (W)w);
-}
 #ifndef SA_RESTART
 # define SA_RESTART 0
 #endif
 }
 void
 ev_signal_stop (EV_P_ ev_signal *w)
 {
-  ev_clear_pending (EV_A_ (W)w);
+  clear_pending (EV_A_ (W)w);
   if (expect_false (!ev_is_active (w)))
     return;
   wlist_del ((WL *)&signals [w->signum - 1].head, (WL)w);
   ev_stop (EV_A_ (W)w);
 #endif
   if (expect_false (ev_is_active (w)))
     return;
   ev_start (EV_A_ (W)w, 1);
-  wlist_add ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
+  wlist_add ((WL *)&childs [w->pid & (EV_PID_HASHSIZE - 1)], (WL)w);
 }
 void
 ev_child_stop (EV_P_ ev_child *w)
 {
-  ev_clear_pending (EV_A_ (W)w);
+  clear_pending (EV_A_ (W)w);
   if (expect_false (!ev_is_active (w)))
     return;
-  wlist_del ((WL *)&childs [w->pid & (PID_HASHSIZE - 1)], (WL)w);
+  wlist_del ((WL *)&childs [w->pid & (EV_PID_HASHSIZE - 1)], (WL)w);
   ev_stop (EV_A_ (W)w);
 }
-#if EV_MULTIPLICITY
+#if EV_STAT_ENABLE
+# ifdef _WIN32
+#  undef lstat
+#  define lstat(a,b) _stati64 (a,b)
+# endif
+#define DEF_STAT_INTERVAL 5.0074891
+#define MIN_STAT_INTERVAL 0.1074891
+static void noinline stat_timer_cb (EV_P_ ev_timer *w_, int revents);
+#if EV_USE_INOTIFY
+# define EV_INOTIFY_BUFSIZE 8192
+static void noinline
+infy_add (EV_P_ ev_stat *w)
+{
+  w->wd = inotify_add_watch (fs_fd, w->path, IN_ATTRIB | IN_DELETE_SELF | IN_MOVE_SELF | IN_MODIFY | IN_DONT_FOLLOW | IN_MASK_ADD);
+  if (w->wd < 0)
+    {
+      ev_timer_start (EV_A_ &w->timer); /* this is not race-free, so we still need to recheck periodically */
+      /* monitor some parent directory for speedup hints */
+      if ((errno == ENOENT || errno == EACCES) && strlen (w->path) < 4096)
+        {
+          char path [4096];
+          strcpy (path, w->path);
+          do
+            {
+              int mask = IN_MASK_ADD | IN_DELETE_SELF | IN_MOVE_SELF
+                       | (errno == EACCES ? IN_ATTRIB : IN_CREATE | IN_MOVED_TO);
+              char *pend = strrchr (path, '/');
+              if (!pend)
+                break; /* whoops, no '/', complain to your admin */
+              *pend = 0;
+              w->wd = inotify_add_watch (fs_fd, path, mask);
+            }
+          while (w->wd < 0 && (errno == ENOENT || errno == EACCES));
+        }
+    }
+  else
+    ev_timer_stop (EV_A_ &w->timer); /* we can watch this in a race-free way */
+  if (w->wd >= 0)
+    wlist_add (&fs_hash [w->wd & (EV_INOTIFY_HASHSIZE - 1)].head, (WL)w);
+}
+static void noinline
+infy_del (EV_P_ ev_stat *w)
+{
+  int slot;
+  int wd = w->wd;
+  if (wd < 0)
+    return;
+  w->wd = -2;
+  slot = wd & (EV_INOTIFY_HASHSIZE - 1);
+  wlist_del (&fs_hash [slot].head, (WL)w);
+  /* remove this watcher, if others are watching it, they will rearm */
+  inotify_rm_watch (fs_fd, wd);
+}
+static void noinline
+infy_wd (EV_P_ int slot, int wd, struct inotify_event *ev)
+{
+  if (slot < 0)
+    /* overflow, need to check for all hahs slots */
+    for (slot = 0; slot < EV_INOTIFY_HASHSIZE; ++slot)
+      infy_wd (EV_A_ slot, wd, ev);
+  else
+    {
+      WL w_;
+      for (w_ = fs_hash [slot & (EV_INOTIFY_HASHSIZE - 1)].head; w_; )
+        {
+          ev_stat *w = (ev_stat *)w_;
+          w_ = w_->next; /* lets us remove this watcher and all before it */
+          if (w->wd == wd || wd == -1)
+            {
+              if (ev->mask & (IN_IGNORED | IN_UNMOUNT | IN_DELETE_SELF))
+                {
+                  w->wd = -1;
+                  infy_add (EV_A_ w); /* re-add, no matter what */
+                }
+              stat_timer_cb (EV_A_ &w->timer, 0);
+            }
+        }
+    }
+}
+static void
+infy_cb (EV_P_ ev_io *w, int revents)
+{
+  char buf [EV_INOTIFY_BUFSIZE];
+  struct inotify_event *ev = (struct inotify_event *)buf;
+  int ofs;
+  int len = read (fs_fd, buf, sizeof (buf));
+  for (ofs = 0; ofs < len; ofs += sizeof (struct inotify_event) + ev->len)
+    infy_wd (EV_A_ ev->wd, ev->wd, ev);
+}
+void inline_size
+infy_init (EV_P)
+{
+  if (fs_fd != -2)
+    return;
+  fs_fd = inotify_init ();
+  if (fs_fd >= 0)
+    {
+      ev_io_init (&fs_w, infy_cb, fs_fd, EV_READ);
+      ev_set_priority (&fs_w, EV_MAXPRI);
+      ev_io_start (EV_A_ &fs_w);
+    }
+}
+void inline_size
+infy_fork (EV_P)
+{
+  int slot;
+  if (fs_fd < 0)
+    return;
+  close (fs_fd);
+  fs_fd = inotify_init ();
+  for (slot = 0; slot < EV_INOTIFY_HASHSIZE; ++slot)
+    {
+      WL w_ = fs_hash [slot].head;
+      fs_hash [slot].head = 0;
+      while (w_)
+        {
+          ev_stat *w = (ev_stat *)w_;
+          w_ = w_->next; /* lets us add this watcher */
+          w->wd = -1;
+          if (fs_fd >= 0)
+            infy_add (EV_A_ w); /* re-add, no matter what */
+          else
+            ev_timer_start (EV_A_ &w->timer);
+        }
+    }
+}
+#endif
 void
+ev_stat_stat (EV_P_ ev_stat *w)
+{
+  if (lstat (w->path, &w->attr) < 0)
+    w->attr.st_nlink = 0;
+  else if (!w->attr.st_nlink)
+    w->attr.st_nlink = 1;
+}
+static void noinline
+stat_timer_cb (EV_P_ ev_timer *w_, int revents)
+{
+  ev_stat *w = (ev_stat *)(((char *)w_) - offsetof (ev_stat, timer));
+  /* we copy this here each the time so that */
+  /* prev has the old value when the callback gets invoked */
+  w->prev = w->attr;
+  ev_stat_stat (EV_A_ w);
+  /* memcmp doesn't work on netbsd, they.... do stuff to their struct stat */
+  if (
+    w->prev.st_dev      != w->attr.st_dev
+    || w->prev.st_ino   != w->attr.st_ino
+    || w->prev.st_mode  != w->attr.st_mode
+    || w->prev.st_nlink != w->attr.st_nlink
+    || w->prev.st_uid   != w->attr.st_uid
+    || w->prev.st_gid   != w->attr.st_gid
+    || w->prev.st_rdev  != w->attr.st_rdev
+    || w->prev.st_size  != w->attr.st_size
+    || w->prev.st_atime != w->attr.st_atime
+    || w->prev.st_mtime != w->attr.st_mtime
+    || w->prev.st_ctime != w->attr.st_ctime
+  ) {
+      #if EV_USE_INOTIFY
+        infy_del (EV_A_ w);
+        infy_add (EV_A_ w);
+        ev_stat_stat (EV_A_ w); /* avoid race... */
+      #endif
+      ev_feed_event (EV_A_ w, EV_STAT);
+    }
+}
+void
+ev_stat_start (EV_P_ ev_stat *w)
+{
+  if (expect_false (ev_is_active (w)))
+    return;
+  /* since we use memcmp, we need to clear any padding data etc. */
+  memset (&w->prev, 0, sizeof (ev_statdata));
+  memset (&w->attr, 0, sizeof (ev_statdata));
+  ev_stat_stat (EV_A_ w);
+  if (w->interval < MIN_STAT_INTERVAL)
+    w->interval = w->interval ? MIN_STAT_INTERVAL : DEF_STAT_INTERVAL;
+  ev_timer_init (&w->timer, stat_timer_cb, w->interval, w->interval);
+  ev_set_priority (&w->timer, ev_priority (w));
+#if EV_USE_INOTIFY
+  infy_init (EV_A);
+  if (fs_fd >= 0)
+    infy_add (EV_A_ w);
+  else
+#endif
+    ev_timer_start (EV_A_ &w->timer);
+  ev_start (EV_A_ (W)w, 1);
+}
+void
+ev_stat_stop (EV_P_ ev_stat *w)
+{
+  clear_pending (EV_A_ (W)w);
+  if (expect_false (!ev_is_active (w)))
+    return;
+#if EV_USE_INOTIFY
+  infy_del (EV_A_ w);
+#endif
+  ev_timer_stop (EV_A_ &w->timer);
+  ev_stop (EV_A_ (W)w);
+}
+#endif
+#if EV_IDLE_ENABLE
+void
+ev_idle_start (EV_P_ ev_idle *w)
+{
+  if (expect_false (ev_is_active (w)))
+    return;
+  pri_adjust (EV_A_ (W)w);
+  {
+    int active = ++idlecnt [ABSPRI (w)];
+    ++idleall;
+    ev_start (EV_A_ (W)w, active);
+    array_needsize (ev_idle *, idles [ABSPRI (w)], idlemax [ABSPRI (w)], active, EMPTY2);
+    idles [ABSPRI (w)][active - 1] = w;
+  }
+}
+void
+ev_idle_stop (EV_P_ ev_idle *w)
+{
+  clear_pending (EV_A_ (W)w);
+  if (expect_false (!ev_is_active (w)))
+    return;
+  {
+    int active = ((W)w)->active;
+    idles [ABSPRI (w)][active - 1] = idles [ABSPRI (w)][--idlecnt [ABSPRI (w)]];
+    ((W)idles [ABSPRI (w)][active - 1])->active = active;
+    ev_stop (EV_A_ (W)w);
+    --idleall;
+  }
+}
+#endif
+void
+ev_prepare_start (EV_P_ ev_prepare *w)
+{
+  if (expect_false (ev_is_active (w)))
+    return;
+  ev_start (EV_A_ (W)w, ++preparecnt);
+  array_needsize (ev_prepare *, prepares, preparemax, preparecnt, EMPTY2);
+  prepares [preparecnt - 1] = w;
+}
+void
+ev_prepare_stop (EV_P_ ev_prepare *w)
+{
+  clear_pending (EV_A_ (W)w);
+  if (expect_false (!ev_is_active (w)))
+    return;
+  {
+    int active = ((W)w)->active;
+    prepares [active - 1] = prepares [--preparecnt];
+    ((W)prepares [active - 1])->active = active;
+  }
+  ev_stop (EV_A_ (W)w);
+}
+void
+ev_check_start (EV_P_ ev_check *w)
+{
+  if (expect_false (ev_is_active (w)))
+    return;
+  ev_start (EV_A_ (W)w, ++checkcnt);
+  array_needsize (ev_check *, checks, checkmax, checkcnt, EMPTY2);
+  checks [checkcnt - 1] = w;
+}
+void
+ev_check_stop (EV_P_ ev_check *w)
+{
+  clear_pending (EV_A_ (W)w);
+  if (expect_false (!ev_is_active (w)))
+    return;
+  {
+    int active = ((W)w)->active;
+    checks [active - 1] = checks [--checkcnt];
+    ((W)checks [active - 1])->active = active;
+  }
+  ev_stop (EV_A_ (W)w);
+}
+#if EV_EMBED_ENABLE
+void noinline
-ev_embed_loop (EV_P_ ev_embed *w)
+ev_embed_sweep (EV_P_ ev_embed *w)
 {
   ev_loop (w->loop, EVLOOP_NONBLOCK);
 }
 static void
   ev_embed *w = (ev_embed *)(((char *)io) - offsetof (ev_embed, io));
   if (ev_cb (w))
     ev_feed_event (EV_A_ (W)w, EV_EMBED);
   else
-    ev_embed_loop (loop, w);
+    ev_embed_sweep (loop, w);
 }
 void
 ev_embed_start (EV_P_ ev_embed *w)
 {
     ev_io_init (&w->io, embed_cb, backend_fd, EV_READ);
   }
   ev_set_priority (&w->io, ev_priority (w));
   ev_io_start (EV_A_ &w->io);
   ev_start (EV_A_ (W)w, 1);
 }
 void
 ev_embed_stop (EV_P_ ev_embed *w)
 {
-  ev_clear_pending (EV_A_ (W)w);
+  clear_pending (EV_A_ (W)w);
   if (expect_false (!ev_is_active (w)))
     return;
   ev_io_stop (EV_A_ &w->io);
+  ev_stop (EV_A_ (W)w);
+}
+#endif
+#if EV_FORK_ENABLE
+void
+ev_fork_start (EV_P_ ev_fork *w)
+{
+  if (expect_false (ev_is_active (w)))
+    return;
+  ev_start (EV_A_ (W)w, ++forkcnt);
+  array_needsize (ev_fork *, forks, forkmax, forkcnt, EMPTY2);
+  forks [forkcnt - 1] = w;
+}
+void
+ev_fork_stop (EV_P_ ev_fork *w)
+{
+  clear_pending (EV_A_ (W)w);
+  if (expect_false (!ev_is_active (w)))
+    return;
+  {
+    int active = ((W)w)->active;
+    forks [active - 1] = forks [--forkcnt];
+    ((W)forks [active - 1])->active = active;
+  }
   ev_stop (EV_A_ (W)w);
 }
 #endif
 /*****************************************************************************/

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Comparing libev/ev.c (file contents): Revision 1.136 by root, Sat Nov 24 07:14:26 2007 UTC vs. Revision 1.170 by root, Sat Dec 8 22:11:14 2007 UTC

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Comparing libev/ev.c (file contents):
Revision 1.136 by root, Sat Nov 24 07:14:26 2007 UTC vs.
Revision 1.170 by root, Sat Dec 8 22:11:14 2007 UTC