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-rw-r--r--ports/sysdeps/unix/sysv/linux/generic/select.c74
1 files changed, 74 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/generic/select.c b/ports/sysdeps/unix/sysv/linux/generic/select.c
new file mode 100644
index 0000000000..143ebc9a07
--- /dev/null
+++ b/ports/sysdeps/unix/sysv/linux/generic/select.c
@@ -0,0 +1,74 @@
+/* Copyright (C) 2011 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sys/time.h>
+#include <sys/types.h>
+#include <sys/select.h>
+#include <errno.h>
+#include <sysdep-cancel.h>
+
+/* Check the first NFDS descriptors each in READFDS (if not NULL) for read
+   readiness, in WRITEFDS (if not NULL) for write readiness, and in EXCEPTFDS
+   (if not NULL) for exceptional conditions.  If TIMEOUT is not NULL, time out
+   after waiting the interval specified therein.  Returns the number of ready
+   descriptors, or -1 for errors.  */
+
+int
+__select(int nfds, fd_set *readfds,
+         fd_set *writefds, fd_set *exceptfds,
+         struct timeval *timeout)
+{
+  int result;
+  struct timespec ts, *tsp = NULL;
+
+  if (timeout)
+    {
+      TIMEVAL_TO_TIMESPEC (timeout, &ts);
+      tsp = &ts;
+    }
+
+  if (SINGLE_THREAD_P)
+    {
+      result = INLINE_SYSCALL (pselect6, 6, nfds, readfds, writefds, exceptfds,
+                               tsp, NULL);
+    }
+  else
+    {
+      int oldtype = LIBC_CANCEL_ASYNC ();
+
+      result = INLINE_SYSCALL (pselect6, 6, nfds, readfds, writefds, exceptfds,
+                               tsp, NULL);
+
+      LIBC_CANCEL_RESET (oldtype);
+    }
+
+  if (timeout)
+    {
+      /* Linux by default will update the timeout after a pselect6 syscall
+         (though the pselect() glibc call suppresses this behavior).
+         Since select() on Linux has the same behavior as the pselect6
+         syscall, we update the timeout here.  */
+      TIMESPEC_TO_TIMEVAL (timeout, &ts);
+    }
+
+  return result;
+}
+libc_hidden_def (__select)
+
+weak_alias (__select, select)
+weak_alias (__select, __libc_select)