Changeset fb96152

Timestamp:

Apr 3, 2011, 3:06:00 PM (13 years ago)

Author:

Nelson Elhage <nelhage@mit.edu>

Branches:

master, release-1.10, release-1.8, release-1.9

Children:

8ba9313

Parents:

f2d71cfa

git-author:

Nelson Elhage <nelhage@nelhage.com> (02/24/11 09:59:45)

git-committer:

Nelson Elhage <nelhage@mit.edu> (04/03/11 15:06:00)

Message:

Don't die horribly if perl registers a dispatch and then closes the fd.

Well-behaved perl code should of course remove the dispatch when it
closes the fd, but there's no reason not to be robust to this failure
mode.

File:

• select.c (modified) (3 diffs)

select.c

@@ -1 +1 @@
 #include "owl.h"
+#include <sys/stat.h>
 
 static int dispatch_active = 0;
@@ -353 +354 @@
   owl_select_psa_gc();
   return ret;
+}
+
+static void owl_select_prune_bad_fds(void) {
+  owl_list *dl = owl_global_get_io_dispatch_list(&g);
+  int len, i;
+  struct stat st;
+  owl_io_dispatch *d;
+
+  len = owl_list_get_size(dl);
+  for (i = 0; i < len; i++) {
+    d = owl_list_get_element(dl, i);
+    if (fstat(d->fd, &st) < 0 && errno == EBADF) {
+      owl_function_debugmsg("Pruning defunct dispatch on fd %d.", d->fd);
+      d->needs_gc = 1;
+    }
+  }
+  owl_select_io_dispatch_gc();
 }
 
@@ -416 +434 @@
   ret = pselect(max_fd+1, &r, &w, &e, &timeout, &mask);
 
-  if(ret < 0 && errno == EINTR) {
-    if(owl_global_is_interrupted(&g)) {
-      owl_select_handle_intr(NULL);
+  if(ret < 0) {
+    if (errno == EINTR) {
+      if(owl_global_is_interrupted(&g)) {
+        owl_select_handle_intr(NULL);
+      }
+    } else if (errno == EBADF) {
+      /* Perl must have closed an fd on us without removing it first. */
+      owl_select_prune_bad_fds();
     }
     sigprocmask(SIG_SETMASK, &mask, NULL);