docs

[software/libev.git] / ev_select.c

diff --git a/ev_select.c b/ev_select.c
index 1262f48659bc5d21f0c8f4b2381492cd8c62a192..38a239874b29782d1892b7ad0df8e854523287e2 100644 (file)
--- a/ev_select.c
+++ b/ev_select.c
@@ -1,4 +1,6 @@
 /*
 /*

+ * libev select fd activity backend
+ *

  * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
  * All rights reserved.
  *
  * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
  * All rights reserved.
  *


@@ -27,93 +29,208 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 

-/* for broken bsd's */
-#include <sys/time.h>
-#include <sys/types.h>
-#include <unistd.h>
-
+#ifndef _WIN32

 /* for unix systems */
 /* for unix systems */

-#include <sys/select.h>
+# include <sys/select.h>
+# include <inttypes.h>
+#endif
+
+#ifndef EV_SELECT_USE_FD_SET
+# ifdef NFDBITS
+#  define EV_SELECT_USE_FD_SET 0
+# else
+#  define EV_SELECT_USE_FD_SET 1
+# endif
+#endif
+
+#if EV_SELECT_IS_WINSOCKET
+# undef EV_SELECT_USE_FD_SET
+# define EV_SELECT_USE_FD_SET 1
+# undef EINTR
+# define EINTR WSAEINTR
+# undef EBADF
+# define EBADF WSAENOTSOCK
+# undef ENOMEM
+# define ENOMEM (errno + 1)
+#endif
+
+#if !EV_SELECT_USE_FD_SET
+# define NFDBYTES (NFDBITS / 8)
+#endif

 
 #include <string.h>
 
 #include <string.h>

-#include <inttypes.h>
-
-static unsigned char *vec_ri, *vec_ro, *vec_wi, *vec_wo;
-static int vec_max;

 
 static void
 
 static void

-select_modify (int fd, int oev, int nev)
+select_modify (EV_P_ int fd, int oev, int nev)

 {
 {

-  int offs = fd >> 3;
-  int mask = 1 << (fd & 7);
-
-  if (vec_max < (fd >> 5) + 1)
-    {
-      vec_max = (fd >> 5) + 1;
-
-      vec_ri = (unsigned char *)realloc (vec_ri, vec_max * 4);
-      vec_ro = (unsigned char *)realloc (vec_ro, vec_max * 4); /* could free/malloc */
-      vec_wi = (unsigned char *)realloc (vec_wi, vec_max * 4);
-      vec_wo = (unsigned char *)realloc (vec_wo, vec_max * 4); /* could free/malloc */
-    }
-
-  vec_ri [offs] |= mask;
-  if (!(nev & EV_READ))
-    vec_ri [offs] &= ~mask;
-
-  vec_wi [offs] |= mask;
-  if (!(nev & EV_WRITE))
-    vec_wi [offs] &= ~mask;
+  if (oev == nev)
+    return;
+
+  {
+#if EV_SELECT_USE_FD_SET
+
+    #if EV_SELECT_IS_WINSOCKET
+    SOCKET handle = anfds [fd].handle;
+    #else
+    int handle = fd;
+    #endif
+
+    if (nev & EV_READ)
+      FD_SET (handle, (fd_set *)vec_ri);
+    else
+      FD_CLR (handle, (fd_set *)vec_ri);
+
+    if (nev & EV_WRITE)
+      FD_SET (handle, (fd_set *)vec_wi);
+    else
+      FD_CLR (handle, (fd_set *)vec_wi);
+
+#else
+
+    int word = fd / NFDBITS;
+    int mask = 1UL << (fd % NFDBITS);
+
+    if (vec_max < word + 1)
+      {
+        int new_max = word + 1;
+
+        vec_ri = ev_realloc (vec_ri, new_max * NFDBYTES);
+        vec_ro = ev_realloc (vec_ro, new_max * NFDBYTES); /* could free/malloc */
+        vec_wi = ev_realloc (vec_wi, new_max * NFDBYTES);
+        vec_wo = ev_realloc (vec_wo, new_max * NFDBYTES); /* could free/malloc */
+
+        for (; vec_max < new_max; ++vec_max)
+          ((fd_mask *)vec_ri)[vec_max] =
+          ((fd_mask *)vec_wi)[vec_max] = 0;
+      }
+
+    ((fd_mask *)vec_ri) [word] |= mask;
+    if (!(nev & EV_READ))
+      ((fd_mask *)vec_ri) [word] &= ~mask;
+
+    ((fd_mask *)vec_wi) [word] |= mask;
+    if (!(nev & EV_WRITE))
+      ((fd_mask *)vec_wi) [word] &= ~mask;
+#endif
+  }

 }
 
 }
 

-static void select_poll (ev_tstamp timeout)
+static void
+select_poll (EV_P_ ev_tstamp timeout)

 {
   struct timeval tv;
   int res;
 
 {
   struct timeval tv;
   int res;
 

-  memcpy (vec_ro, vec_ri, vec_max * 4);
-  memcpy (vec_wo, vec_wi, vec_max * 4);
+#if EV_SELECT_USE_FD_SET
+  memcpy (vec_ro, vec_ri, sizeof (fd_set));
+  memcpy (vec_wo, vec_wi, sizeof (fd_set));
+#else
+  memcpy (vec_ro, vec_ri, vec_max * NFDBYTES);
+  memcpy (vec_wo, vec_wi, vec_max * NFDBYTES);
+#endif

 
   tv.tv_sec  = (long)timeout;
   tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
 
 
   tv.tv_sec  = (long)timeout;
   tv.tv_usec = (long)((timeout - (ev_tstamp)tv.tv_sec) * 1e6);
 

-  res = select (vec_max * 32, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);
+  res = select (vec_max * NFDBITS, (fd_set *)vec_ro, (fd_set *)vec_wo, 0, &tv);

 
 

-  if (res > 0)
+  if (res < 0)

     {
     {

-      int word, offs;
+      #if EV_SELECT_IS_WINSOCKET
+      errno = WSAGetLastError ();
+      #endif
+
+      if (errno == EBADF)
+        fd_ebadf (EV_A);
+      else if (errno == ENOMEM && !syserr_cb)
+        fd_enomem (EV_A);
+      else if (errno != EINTR)
+        syserr ("(libev) select");
+
+      return;
+    }
+
+#if EV_SELECT_USE_FD_SET

 
 

-      for (word = vec_max; word--; )
+  {
+    int fd;
+
+    for (fd = 0; fd < anfdmax; ++fd)
+      if (anfds [fd].events)

         {
         {

-          if (((uint32_t *)vec_ro) [word] | ((uint32_t *)vec_wo) [word])
-            for (offs = 4; offs--; )
-              {
-                int idx = word * 4 + offs;
-                unsigned char byte_r = vec_ro [idx];
-                unsigned char byte_w = vec_wo [idx];
-                int bit;
-
-                if (byte_r | byte_w)
-                  for (bit = 8; bit--; )
-                    {
-                      int events = 0;
-                      events |= byte_r & (1 << bit) ? EV_READ  : 0;
-                      events |= byte_w & (1 << bit) ? EV_WRITE : 0;
-
-                      if (events)
-                        fd_event (idx * 8 + bit, events);
-                    }
-              }
+          int events = 0;
+          #if EV_SELECT_IS_WINSOCKET
+          SOCKET handle = anfds [fd].handle;
+          #else
+          int handle = fd;
+          #endif
+
+          if (FD_ISSET (handle, (fd_set *)vec_ro)) events |= EV_READ;
+          if (FD_ISSET (handle, (fd_set *)vec_wo)) events |= EV_WRITE;
+
+          if (events)
+            fd_event (EV_A_ fd, events);

         }
         }

-    }
+  }
+
+#else
+
+  {
+    int word, bit;
+    for (word = vec_max; word--; )
+      {
+        fd_mask word_r = ((fd_mask *)vec_ro) [word];
+        fd_mask word_w = ((fd_mask *)vec_wo) [word];
+
+        if (word_r || word_w)
+          for (bit = NFDBITS; bit--; )
+            {
+              fd_mask mask = 1UL << bit;
+              int events = 0;
+
+              events |= word_r & mask ? EV_READ  : 0;
+              events |= word_w & mask ? EV_WRITE : 0;
+
+              if (events)
+                fd_event (EV_A_ word * NFDBITS + bit, events);
+            }
+      }
+  }
+
+#endif
+}
+
+static int
+select_init (EV_P_ int flags)
+{
+  backend_fudge  = 1e-2; /* needed to compensate for select returning early, very conservative */
+  backend_modify = select_modify;
+  backend_poll   = select_poll;
+
+#if EV_SELECT_USE_FD_SET
+  vec_max = FD_SETSIZE / 32;
+  vec_ri  = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_ri);
+  vec_ro  = ev_malloc (sizeof (fd_set));
+  vec_wi  = ev_malloc (sizeof (fd_set)); FD_ZERO ((fd_set *)vec_wi);
+  vec_wo  = ev_malloc (sizeof (fd_set));
+#else
+  vec_max = 0;
+  vec_ri  = 0; 
+  vec_ri  = 0;   
+  vec_wo  = 0; 
+  vec_wo  = 0; 
+#endif
+
+  return EVBACKEND_SELECT;

 }
 
 }
 

-void select_init (int flags)
+static void
+select_destroy (EV_P)

 {
 {

-  ev_method     = EVMETHOD_SELECT;
-  method_fudge  = 1e-2; /* needed to compensate for select returning early, very conservative */
-  method_modify = select_modify;
-  method_poll   = select_poll;
+  ev_free (vec_ri);
+  ev_free (vec_ro);
+  ev_free (vec_wi);
+  ev_free (vec_wo);

 }
 
 
 }