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

[software/libev.git] / ev_select.c

diff --git a/ev_select.c b/ev_select.c
index 63612dcc9f31fe0aa78d8085f7fc440d16b7a5ee..0333d63949bbce3feb301d98048bfbd674460138 100644 (file)
--- a/ev_select.c
+++ b/ev_select.c
@@ -1,3 +1,34 @@
+/*
+ * libev select fd activity backend
+ *
+ * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *
+ *     * Redistributions in binary form must reproduce the above
+ *       copyright notice, this list of conditions and the following
+ *       disclaimer in the documentation and/or other materials provided
+ *       with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
 /* for broken bsd's */
 #include <sys/time.h>
 #include <sys/types.h>
@@ -20,12 +51,16 @@ select_modify (int fd, int oev, int nev)
 
   if (vec_max < (fd >> 5) + 1)
     {
-      vec_max = (fd >> 5) + 1;
+      int new_max = (fd >> 5) + 1;
+
+      vec_ri = (unsigned char *)realloc (vec_ri, new_max * 4);
+      vec_ro = (unsigned char *)realloc (vec_ro, new_max * 4); /* could free/malloc */
+      vec_wi = (unsigned char *)realloc (vec_wi, new_max * 4);
+      vec_wo = (unsigned char *)realloc (vec_wo, new_max * 4); /* could free/malloc */
 
-      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 */
+      for (; vec_max < new_max; ++vec_max)
+        ((uint32_t *)vec_ri)[vec_max] =
+        ((uint32_t *)vec_wi)[vec_max] = 0;
     }
 
   vec_ri [offs] |= mask;
@@ -37,7 +72,8 @@ select_modify (int fd, int oev, int nev)
     vec_wi [offs] &= ~mask;
 }
 
-static void select_poll (ev_tstamp timeout)
+static void
+select_poll (ev_tstamp timeout)
 {
   struct timeval tv;
   int res;
@@ -77,16 +113,21 @@ static void select_poll (ev_tstamp timeout)
               }
         }
     }
+  else if (res < 0)
+    {
+      if (errno == EBADF)
+        fd_ebadf ();
+      else if (errno == ENOMEM)
+        fd_enomem ();
+    }
 }
 
-int select_init (int flags)
+static void
+select_init (int flags)
 {
-  ev_method = EVMETHOD_SELECT;
+  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;
-
-  return 1;
 }
 
-