implement poll method, handle enomem by closing a 'random' fd

[software/libev.git] / ev.c

diff --git a/ev.c b/ev.c
index 46c8cea08e9a74c312b67e8152e68e0dd4f5556e..c77ad2ac642278ef57cef35011ed9d24a5bcbc1d 100644 (file)
--- a/ev.c
+++ b/ev.c
@@ -48,42 +48,65 @@
 #include <sys/time.h>
 #include <time.h>
 
 #include <sys/time.h>
 #include <time.h>
 

+/**/
+

 #ifndef EV_USE_MONOTONIC
 # define EV_USE_MONOTONIC 1
 #endif
 
 #ifndef EV_USE_MONOTONIC
 # define EV_USE_MONOTONIC 1
 #endif
 

-#ifndef CLOCK_MONOTONIC
-# undef EV_USE_MONOTONIC
-# define EV_USE_MONOTONIC 0
-#endif
-

 #ifndef EV_USE_SELECT
 # define EV_USE_SELECT 1
 #endif
 
 #ifndef EV_USE_SELECT
 # define EV_USE_SELECT 1
 #endif
 

+#ifndef EV_USE_POLL
+# define EV_USE_POLL 0 /* poll is usually slower than select, and not as well tested */
+#endif
+

 #ifndef EV_USE_EPOLL
 # define EV_USE_EPOLL 0
 #endif
 
 #ifndef EV_USE_EPOLL
 # define EV_USE_EPOLL 0
 #endif
 

+#ifndef EV_USE_REALTIME
+# define EV_USE_REALTIME 1
+#endif
+
+/**/
+
+#ifndef CLOCK_MONOTONIC
+# undef EV_USE_MONOTONIC
+# define EV_USE_MONOTONIC 0
+#endif
+

 #ifndef CLOCK_REALTIME
 #ifndef CLOCK_REALTIME

+# undef EV_USE_REALTIME

 # define EV_USE_REALTIME 0
 #endif
 # define EV_USE_REALTIME 0
 #endif

-#ifndef EV_USE_REALTIME
-# define EV_USE_REALTIME 1 /* posix requirement, but might be slower */
-#endif
+
+/**/

 
 #define MIN_TIMEJUMP  1. /* minimum timejump that gets detected (if monotonic clock available) */
 
 #define MIN_TIMEJUMP  1. /* minimum timejump that gets detected (if monotonic clock available) */

-#define MAX_BLOCKTIME 59.731 /* never wait longer than this time (to detetc time jumps) */
+#define MAX_BLOCKTIME 59.731 /* 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 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 */
+/*#define CLEANUP_INTERVAL 300. /* how often to try to free memory and re-check fds */

 
 #include "ev.h"
 
 
 #include "ev.h"
 

+#if __GNUC__ >= 3
+# define expect(expr,value)         __builtin_expect ((expr),(value))
+# define inline                     inline
+#else
+# define expect(expr,value)         (expr)
+# define inline                     static
+#endif
+
+#define expect_false(expr) expect ((expr) != 0, 0)
+#define expect_true(expr)  expect ((expr) != 0, 1)
+

 typedef struct ev_watcher *W;
 typedef struct ev_watcher_list *WL;
 typedef struct ev_watcher_time *WT;
 
 typedef struct ev_watcher *W;
 typedef struct ev_watcher_list *WL;
 typedef struct ev_watcher_time *WT;
 

-static ev_tstamp now, diff; /* monotonic clock */
+static ev_tstamp now_floor, now, diff; /* monotonic clock */

 ev_tstamp ev_now;
 int ev_method;
 
 ev_tstamp ev_now;
 int ev_method;
 


@@ -113,7 +136,7 @@ static ev_tstamp
 get_clock (void)
 {
 #if EV_USE_MONOTONIC
 get_clock (void)
 {
 #if EV_USE_MONOTONIC

-  if (have_monotonic)
+  if (expect_true (have_monotonic))

     {
       struct timespec ts;
       clock_gettime (CLOCK_MONOTONIC, &ts);
     {
       struct timespec ts;
       clock_gettime (CLOCK_MONOTONIC, &ts);


@@ -127,7 +150,7 @@ get_clock (void)
 #define array_roundsize(base,n) ((n) | 4 & ~3)
 
 #define array_needsize(base,cur,cnt,init)              \
 #define array_roundsize(base,n) ((n) | 4 & ~3)
 
 #define array_needsize(base,cur,cnt,init)              \

-  if ((cnt) > cur)                                     \
+  if (expect_false ((cnt) > cur))                      \

     {                                                  \
       int newcnt = cur;                                        \
       do                                               \
     {                                                  \
       int newcnt = cur;                                        \
       do                                               \


@@ -260,20 +283,44 @@ fd_change (int fd)
   fdchanges [fdchangecnt - 1] = fd;
 }
 
   fdchanges [fdchangecnt - 1] = fd;
 }
 

+static void
+fd_kill (int fd)
+{
+  struct ev_io *w;
+
+  printf ("killing fd %d\n", fd);//D
+  while ((w = anfds [fd].head))
+    {
+      ev_io_stop (w);
+      event ((W)w, EV_ERROR | EV_READ | EV_WRITE);
+    }
+}
+

 /* called on EBADF to verify fds */
 static void
 /* called on EBADF to verify fds */
 static void

-fd_recheck (void)
+fd_ebadf (void)

 {
   int fd;
 
   for (fd = 0; fd < anfdmax; ++fd)
     if (anfds [fd].events)
       if (fcntl (fd, F_GETFD) == -1 && errno == EBADF)
 {
   int fd;
 
   for (fd = 0; fd < anfdmax; ++fd)
     if (anfds [fd].events)
       if (fcntl (fd, F_GETFD) == -1 && errno == EBADF)

-        while (anfds [fd].head)
-          {
-            ev_io_stop (anfds [fd].head);
-            event ((W)anfds [fd].head, EV_ERROR | EV_READ | EV_WRITE);
-          }
+        fd_kill (fd);
+}
+
+/* called on ENOMEM in select/poll to kill some fds and retry */
+static void
+fd_enomem (void)
+{
+  int fd = anfdmax;
+
+  while (fd--)
+    if (anfds [fd].events)
+      {
+        close (fd);
+        fd_kill (fd);
+        return;
+      }

 }
 
 /*****************************************************************************/
 }
 
 /*****************************************************************************/


@@ -437,6 +484,9 @@ childcb (struct ev_signal *sw, int revents)
 #if EV_USE_EPOLL
 # include "ev_epoll.c"
 #endif
 #if EV_USE_EPOLL
 # include "ev_epoll.c"
 #endif

+#if EV_USE_POLL
+# include "ev_poll.c"
+#endif

 #if EV_USE_SELECT
 # include "ev_select.c"
 #endif
 #if EV_USE_SELECT
 # include "ev_select.c"
 #endif


@@ -453,7 +503,15 @@ ev_version_minor (void)
   return EV_VERSION_MINOR;
 }
 
   return EV_VERSION_MINOR;
 }
 

-int ev_init (int flags)
+/* return true if we are running with elevated privileges and ignore env variables */
+static int
+enable_secure ()
+{
+  return getuid () != geteuid ()
+      || getgid () != getegid ();
+}
+
+int ev_init (int methods)

 {
   if (!ev_method)
     {
 {
   if (!ev_method)
     {


@@ -465,19 +523,29 @@ int ev_init (int flags)
       }
 #endif
 
       }
 #endif
 

-      ev_now = ev_time ();
-      now    = get_clock ();
-      diff   = ev_now - now;
+      ev_now    = ev_time ();
+      now       = get_clock ();
+      now_floor = now;
+      diff      = ev_now - now;

 
       if (pipe (sigpipe))
         return 0;
 
 
       if (pipe (sigpipe))
         return 0;
 

-      ev_method = EVMETHOD_NONE;
+      if (methods == EVMETHOD_AUTO)
+          if (!enable_secure () && getenv ("LIBEV_METHODS"))
+            methods = atoi (getenv ("LIBEV_METHODS"));
+          else
+            methods = EVMETHOD_ANY;
+
+      ev_method = 0;

 #if EV_USE_EPOLL
 #if EV_USE_EPOLL

-      if (ev_method == EVMETHOD_NONE) epoll_init (flags);
+      if (!ev_method && (methods & EVMETHOD_EPOLL )) epoll_init  (methods);
+#endif
+#if EV_USE_POLL
+      if (!ev_method && (methods & EVMETHOD_POLL  )) poll_init   (methods);

 #endif
 #if EV_USE_SELECT
 #endif
 #if EV_USE_SELECT

-      if (ev_method == EVMETHOD_NONE) select_init (flags);
+      if (!ev_method && (methods & EVMETHOD_SELECT)) select_init (methods);

 #endif
 
       if (ev_method)
 #endif
 
       if (ev_method)


@@ -606,34 +674,58 @@ periodics_reschedule (ev_tstamp diff)
     }
 }
 
     }
 }
 

+static int
+time_update_monotonic (void)
+{
+  now = get_clock ();
+
+  if (expect_true (now - now_floor < MIN_TIMEJUMP * .5))
+    {
+      ev_now = now + diff;
+      return 0;
+    }
+  else
+    {
+      now_floor = now;
+      ev_now = ev_time ();
+      return 1;
+    }
+}
+

 static void
 time_update (void)
 {
   int i;
 
 static void
 time_update (void)
 {
   int i;
 

-  ev_now = ev_time ();
-
-  if (have_monotonic)
+#if EV_USE_MONOTONIC
+  if (expect_true (have_monotonic))

     {
     {

-      ev_tstamp odiff = diff;
-
-      for (i = 4; --i; ) /* loop a few times, before making important decisions */
+      if (time_update_monotonic ())

         {
         {

-          now = get_clock ();
-          diff = ev_now - now;
+          ev_tstamp odiff = diff;

 
 

-          if (fabs (odiff - diff) < MIN_TIMEJUMP)
-            return; /* all is well */
+          for (i = 4; --i; ) /* loop a few times, before making important decisions */
+            {
+              diff = ev_now - now;

 
 

-          ev_now = ev_time ();
-        }
+              if (fabs (odiff - diff) < MIN_TIMEJUMP)
+                return; /* all is well */
+
+              ev_now    = ev_time ();
+              now       = get_clock ();
+              now_floor = now;
+            }

 
 

-      periodics_reschedule (diff - odiff);
-      /* no timer adjustment, as the monotonic clock doesn't jump */
+          periodics_reschedule (diff - odiff);
+          /* no timer adjustment, as the monotonic clock doesn't jump */
+        }

     }
   else
     }
   else

+#endif

     {
     {

-      if (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP)
+      ev_now = ev_time ();
+
+      if (expect_false (now > ev_now || now < ev_now - MAX_BLOCKTIME - MIN_TIMEJUMP))

         {
           periodics_reschedule (ev_now - now);
 
         {
           periodics_reschedule (ev_now - now);
 


@@ -656,7 +748,7 @@ void ev_loop (int flags)
   do
     {
       /* queue check watchers (and execute them) */
   do
     {
       /* queue check watchers (and execute them) */

-      if (preparecnt)
+      if (expect_false (preparecnt))

         {
           queue_events ((W *)prepares, preparecnt, EV_PREPARE);
           call_pending ();
         {
           queue_events ((W *)prepares, preparecnt, EV_PREPARE);
           call_pending ();


@@ -669,7 +761,15 @@ void ev_loop (int flags)
 
       /* we only need this for !monotonic clockor timers, but as we basically
          always have timers, we just calculate it always */
 
       /* we only need this for !monotonic clockor timers, but as we basically
          always have timers, we just calculate it always */

-      ev_now = ev_time ();
+#if EV_USE_MONOTONIC
+      if (expect_true (have_monotonic))
+        time_update_monotonic ();
+      else
+#endif
+        {
+          ev_now = ev_time ();
+          now    = ev_now;
+        }

 
       if (flags & EVLOOP_NONBLOCK || idlecnt)
         block = 0.;
 
       if (flags & EVLOOP_NONBLOCK || idlecnt)
         block = 0.;


@@ -679,7 +779,7 @@ void ev_loop (int flags)
 
           if (timercnt)
             {
 
           if (timercnt)
             {

-              ev_tstamp to = timers [0]->at - (have_monotonic ? get_clock () : ev_now) + method_fudge;
+              ev_tstamp to = timers [0]->at - now + method_fudge;

               if (block > to) block = to;
             }
 
               if (block > to) block = to;
             }