select.c

/*
# _____     ___ ____     ___ ____
#  ____|   |    ____|   |        | |____|
# |     ___|   |____ ___|    ____| |    \    PS2DEV Open Source Project.
#-----------------------------------------------------------------------
# Copyright ps2dev - http://www.ps2dev.org
# Licenced under Academic Free License version 2.0
# Review ps2sdk README & LICENSE files for further details.
*/
 
#define LIBCGLUE_SYS_SOCKET_NO_ALIASES
#define LIBCGLUE_ARPA_INET_NO_ALIASES
#include <sys/socket.h>
#include <ps2sdkapi.h>
#include <errno.h>
 
#include "ps2sdkapi.h"
 
/* FIXME: This function currently cannot handle heterogeneous fds */
int select(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout)
{
    int fd;
    int ret;
    int iop_max_fd = -1;
    fd_set ready_readfds, ready_writefds, ready_exceptfds;
    fd_set iop_readfds, iop_writefds, iop_exceptfds;
 
    if (_libcglue_fdman_socket_ops == NULL || _libcglue_fdman_socket_ops->select == NULL)
    {
        errno = ENOSYS;
        return -1;
    }
 
    FD_ZERO(&ready_readfds);
    FD_ZERO(&ready_writefds);
    FD_ZERO(&ready_exceptfds);
 
    FD_ZERO(&iop_readfds);
    FD_ZERO(&iop_writefds);
    FD_ZERO(&iop_exceptfds);
 
    for (fd = 0; fd < n; fd += 1)
    {
        int in_read   = readfds   && FD_ISSET(fd, readfds);
        int in_write  = writefds  && FD_ISSET(fd, writefds);
        int in_except = exceptfds && FD_ISSET(fd, exceptfds);
        int iop_fd;
 
        if (!in_read && !in_write && !in_except)
        {
            continue;
        }
 
        iop_fd = ps2sdk_get_iop_fd(fd);
        if (iop_fd < 0)
        {
            errno = EBADF;
            return -1;
        }
        if (iop_fd > iop_max_fd)
        {
            iop_max_fd = iop_fd;
        }
        if (in_read)
        {
            FD_SET(iop_fd, &iop_readfds);
        }
        if (in_write)
        {
            FD_SET(iop_fd, &iop_writefds);
        }
        if (in_except)
        {
            FD_SET(iop_fd, &iop_exceptfds);
        }
    }
 
    /* Pass max(iop_fd)+1 to the underlying select, not the EE-side n.
     * The bits in iop_*fds are at iop_fd positions; if iop_fd > n-1 the
     * underlying select would iterate an empty range and block forever
     * waiting for events on bits it isn't watching. */
    ret = _libcglue_fdman_socket_ops->select(iop_max_fd + 1, &iop_readfds, &iop_writefds, &iop_exceptfds, timeout);
 
    for (fd = 0; fd < n; fd += 1)
    {
        int in_read   = readfds   && FD_ISSET(fd, readfds);
        int in_write  = writefds  && FD_ISSET(fd, writefds);
        int in_except = exceptfds && FD_ISSET(fd, exceptfds);
        int iop_fd;
 
        if (!in_read && !in_write && !in_except)
        {
            continue;
        }
 
        iop_fd = ps2sdk_get_iop_fd(fd);
        if (iop_fd < 0)
        {
            continue;
        }
        if (in_read && FD_ISSET(iop_fd, &iop_readfds))
        {
            FD_SET(fd, &ready_readfds);
        }
        if (in_write && FD_ISSET(iop_fd, &iop_writefds))
        {
            FD_SET(fd, &ready_writefds);
        }
        if (in_except && FD_ISSET(iop_fd, &iop_exceptfds))
        {
            FD_SET(fd, &ready_exceptfds);
        }
    }
 
    if (readfds)
    {
        *readfds = ready_readfds;
    }
    if (writefds)
    {
        *writefds = ready_writefds;
    }
    if (exceptfds)
    {
        *exceptfds = ready_exceptfds;
    }
 
    return ret;
}