/* Extended Module Player
 * Copyright (C) 1996-1999 Claudio Matsuoka and Hipolito Carraro Jr
 *
 * This file is part of the Extended Module Player and is distributed
 * under the terms of the GNU General Public License. See doc/COPYING
 * for more information.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/ipc.h>

#ifndef __EMX__
   #include <sys/shm.h>
#endif

#include <unistd.h>
#include "xmpi.h"


#ifdef __EMX__

#define INCL_DOSMEMMGR
#include <os2.h>
#include <io.h>
char *os2mem;

int shmget(int flag1, int amt, int flag2){
   DosAllocSharedMem( (PVOID*)&os2mem, (PSZ)NULL, amt, fALLOC | OBJ_GETTABLE );
   return(1);
}
char *shmat(int id, int a, int b){
   return(os2mem);
}
void shmctl(int id, int flag, char *tmp){
   return;
}
void shmdt(char *memptr){
   DosFreeMem( memptr );
}

#endif



/* shared memory */
static int shmid;

void *xmp_get_shared_mem (int n)
{
    char *p;

    if ((shmid = shmget (IPC_PRIVATE, n, IPC_CREAT | 0600)) == -1)
	return NULL;

    p = shmat (shmid, 0, 0);
    memset (p, 0, n);

    return p;
}


void xmp_detach_shared_mem (void *p)
{
    shmctl (shmid, IPC_RMID, NULL);
    shmdt (p);
}


/* pipes for parent-child synchronization */
static int pfd1[2], pfd2[2];

int xmpi_tell_wait ()
{
    return (pipe (pfd1) || pipe (pfd2));
}


int xmpi_select_read (int fd, int msec)
{
    fd_set rfds;
    struct timeval tv;

    tv.tv_sec = msec / 1000;
    tv.tv_usec = (msec % 1000) * 1000;
    FD_ZERO (&rfds);
    FD_SET (fd, &rfds);

    return select (fd + 1, &rfds, NULL, NULL, &tv);
}


int xmp_tell_parent ()
{
    return write (pfd2[1], "c", 1) != 1;
}


int xmp_wait_parent ()
{
    char c;

    return !((read (pfd1[0], &c, 1) == 1) && (c == 'p'));
}



int xmp_check_parent (int msec)
{
    return xmpi_select_read (pfd1[0], msec);
}


int xmp_tell_child ()
{
    return write (pfd1[1], "p", 1) != 1;
}


int xmp_wait_child ()
{
    char c;

    return !((read (pfd2[0], &c, 1) == 1) && (c == 'c'));
}


int xmp_check_child (int msec)
{
    return xmpi_select_read (pfd2[0], msec);
}