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/**************************************************************************/
/* */
/* OCaml */
/* */
/* Xavier Leroy, projet Cristal, INRIA Rocquencourt */
/* */
/* Copyright 1996 Institut National de Recherche en Informatique et */
/* en Automatique. */
/* */
/* All rights reserved. This file is distributed under the terms of */
/* the GNU Lesser General Public License version 2.1, with the */
/* special exception on linking described in the file LICENSE. */
/* */
/**************************************************************************/
#include <caml/mlvalues.h>
#include <caml/alloc.h>
#include <caml/fail.h>
#include <caml/memory.h>
#include <caml/signals.h>
#include "unixsupport.h"
#ifdef HAS_SELECT
#include <sys/types.h>
#include <sys/time.h>
#ifdef HAS_SYS_SELECT_H
#include <sys/select.h>
#endif
#include <string.h>
#include <unistd.h>
#include <errno.h>
static int fdlist_to_fdset(value fdlist, fd_set *fdset, int *maxfd)
{
value l;
FD_ZERO(fdset);
for (l = fdlist; l != Val_emptylist; l = Field(l, 1)) {
long fd = Long_val(Field(l, 0));
/* PR#5563: harden against bad fds */
if (fd < 0 || fd >= FD_SETSIZE) return -1;
FD_SET((int) fd, fdset);
if (fd > *maxfd) *maxfd = fd;
}
return 0;
}
static value fdset_to_fdlist(value fdlist, fd_set *fdset)
{
CAMLparam0();
CAMLlocal2(l, res);
for (l = fdlist; l != Val_emptylist; l = Field(l, 1)) {
int fd = Int_val(Field(l, 0));
if (FD_ISSET(fd, fdset)) {
value newres = caml_alloc_small(2, Tag_cons);
Field(newres, 0) = Val_int(fd);
Field(newres, 1) = res;
res = newres;
}
}
CAMLreturn(res);
}
CAMLprim value caml_unix_select(value readfds, value writefds, value exceptfds,
value timeout)
{
CAMLparam3(readfds, writefds, exceptfds);
fd_set read, write, except;
int maxfd;
double tm;
struct timeval tv;
struct timeval * tvp;
int retcode;
value res;
maxfd = -1;
retcode = fdlist_to_fdset(readfds, &read, &maxfd);
retcode += fdlist_to_fdset(writefds, &write, &maxfd);
retcode += fdlist_to_fdset(exceptfds, &except, &maxfd);
/* PR#5563: if a bad fd was encountered, report EINVAL error */
if (retcode != 0) caml_unix_error(EINVAL, "select", Nothing);
tm = Double_val(timeout);
if (tm < 0.0)
tvp = (struct timeval *) NULL;
else {
tv.tv_sec = (int) tm;
tv.tv_usec = (int) (1e6 * (tm - tv.tv_sec));
tvp = &tv;
}
caml_enter_blocking_section();
retcode = select(maxfd + 1, &read, &write, &except, tvp);
caml_leave_blocking_section();
if (retcode == -1) caml_uerror("select", Nothing);
readfds = fdset_to_fdlist(readfds, &read);
writefds = fdset_to_fdlist(writefds, &write);
exceptfds = fdset_to_fdlist(exceptfds, &except);
res = caml_alloc_small(3, 0);
Field(res, 0) = readfds;
Field(res, 1) = writefds;
Field(res, 2) = exceptfds;
CAMLreturn(res);
}
#else
CAMLprim value caml_unix_select(value readfds, value writefds, value exceptfds,
value timeout)
{ caml_invalid_argument("select not implemented"); }
#endif
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