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#include <mlvalues.h>
#include <alloc.h>
#include <memory.h>
#include "unix.h"
#ifdef HAS_SELECT
#include <sys/types.h>
#include <sys/time.h>
#ifdef FD_ISSET
typedef fd_set file_descr_set;
#else
typedef int file_descr_set;
#define FD_SETSIZE (sizeof(int) * 8)
#define FD_SET(fd,fds) (*(fds) |= 1 << (fd))
#define FD_CLR(fd,fds) (*(fds) &= ~(1 << (fd)))
#define FD_ISSET(fd,fds) (*(fds) & (1 << (fd)))
#define FD_ZERO(fds) (*(fds) = 0)
#endif
static void fdlist_to_fdset(fdlist, fdset)
value fdlist;
file_descr_set * fdset;
{
value l;
FD_ZERO(fdset);
for (l = fdlist; l != Val_int(0); l = Field(l, 1)) {
FD_SET(Int_val(Field(l, 0)), fdset);
}
}
static value fdset_to_fdlist(fdset)
file_descr_set * fdset;
{
int i;
Push_roots(roots, 1)
#define res roots[0]
res = Val_int(0);
for (i = FD_SETSIZE - 1; i >= 0; i--) {
if (FD_ISSET(i, fdset)) {
value newres = alloc(2, 0);
Field(newres, 0) = Val_int(i);
Field(newres, 1) = res;
res = newres;
}
}
Pop_roots();
return res;
#undef res
}
value unix_select(readfds, writefds, exceptfds, timeout) /* ML */
value readfds, writefds, exceptfds, timeout;
{
file_descr_set read, write, except;
double tm;
struct timeval tv;
struct timeval * tvp;
int retcode;
value res;
Push_roots(roots, 3)
#define read_list roots[0]
#define write_list roots[1]
#define except_list roots[2]
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;
}
retcode = select(FD_SETSIZE, &read, &write, &except, tvp);
if (retcode == -1) uerror("select", Nothing);
read_list = fdset_to_fdlist(&read);
write_list = fdset_to_fdlist(&write);
except_list = fdset_to_fdlist(&except);
res = alloc_tuple(3);
Field(res, 0) = read_list;
Field(res, 1) = write_list;
Field(res, 2) = except_list;
Pop_roots();
return res;
#undef read_list
#undef write_list
#undef except_list
}
#else
value unix_select() { invalid_argument("select not implemented"); }
#endif
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