1 files changed, 84 insertions, 0 deletions
diff --git a/otherlibs/win32unix/select.c b/otherlibs/win32unix/select.c
new file mode 100644
index 000000000..ca12b93ce
--- /dev/null
+++ b/otherlibs/win32unix/select.c
@@ -0,0 +1,84 @@
+/***********************************************************************/
+/*                                                                     */
+/*                           Objective Caml                            */
+/*                                                                     */
+/*            Xavier Leroy, projet Cristal, INRIA Rocquencourt         */
+/*                                                                     */
+/*  Copyright 1996 Institut National de Recherche en Informatique et   */
+/*  Automatique.  Distributed only by permission.                      */
+/*                                                                     */
+/***********************************************************************/
+
+/* $Id$ */
+
+#include <mlvalues.h>
+#include <alloc.h>
+#include <memory.h>
+#include <signals.h>
+#include "unixsupport.h"
+#include <winsock.h>
+
+static void fdlist_to_fdset(value fdlist, fd_set *fdset)
+{
+  value l;
+  FD_ZERO(fdset);
+  for (l = fdlist; l != Val_int(0); l = Field(l, 1)) {
+    FD_SET((SOCKET) Handle_val(Field(l, 0)), fdset);
+  }
+}
+
+static value fdset_to_fdlist(value fdlist, fd_set *fdset)
+{
+  value res = Val_int(0);
+  Begin_roots2(fdlist, res)
+    for (/*nothing*/; fdlist != Val_int(0); fdlist = Field(fdlist, 1)) {
+      value s = Field(fdlist, 0);
+      if (FD_ISSET((SOCKET) Handle_val(s), fdset)) {
+	value newres = alloc(2, 0);
+	Field(newres, 0) = s;
+	Field(newres, 1) = res;
+	res = newres;
+      }
+    }
+  End_roots();
+  return res;
+}
+
+value unix_select(value readfds, value writefds, value exceptfds, value timeout) /* ML */
+{
+  fd_set read, write, except;
+  double tm;
+  struct timeval tv;
+  struct timeval * tvp;
+  int retcode;
+  value res;
+  value read_list = Val_unit, write_list = Val_unit, except_list = Val_unit;
+
+  Begin_roots3 (readfds, writefds, exceptfds)
+  Begin_roots3 (read_list, write_list, except_list)
+    fdlist_to_fdset(readfds, &read);
+    fdlist_to_fdset(writefds, &write);
+    fdlist_to_fdset(exceptfds, &except);
+    tm = Double_val(timeout);
+    if (tm < 0.0)
+      tvp = (struct timeval *) NULL;
+    else {
+      tv.tv_sec = (int) tm;
+      tv.tv_usec = (int) (1e6 * (tm - (int) tm));
+      tvp = &tv;
+    }
+    enter_blocking_section();
+    retcode = select(FD_SETSIZE, &read, &write, &except, tvp);
+    leave_blocking_section();
+    if (retcode == -1) unix_error(WSAGetLastError(), "select", Nothing);
+    read_list = fdset_to_fdlist(readfds, &read);
+    write_list = fdset_to_fdlist(writefds, &write);
+    except_list = fdset_to_fdlist(exceptfds, &except);
+    res = alloc_tuple(3);
+    Field(res, 0) = read_list;
+    Field(res, 1) = write_list;
+    Field(res, 2) = except_list;
+  End_roots();
+  End_roots();
+  return res;
+}