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/*
* ZMailer 2.99.16+ Scheduler "bi-directional-pipe" routines
*
* Copyright Matti Aarnio <mea@nic.funet.fi> 1995
*
*/
#include "hostenv.h"
#include "scheduler.h"
#include "prototypes.h"
#ifdef HAVE_SOCKETPAIR
#include <sys/types.h>
#include <sys/socket.h>
/*
* Life is easy, we have a system with socketpair, we shall use them...
*/
int pipes_create(tochild, fromchild)
int tochild[2];
int fromchild[2];
{
int rc = socketpair(PF_UNIX, SOCK_STREAM, 0, tochild);
if (rc < 0) return rc;
fromchild[0] = tochild[1];
fromchild[1] = tochild[0];
return 0;
}
void pipes_close_parent(tochild, fromchild)
int tochild[2];
int fromchild[2];
{
close(tochild[0]); /* same fd as fromchild[1] */
}
void pipes_to_child_fds(tochild, fromchild)
int tochild[2];
int fromchild[2];
{
if (tochild[0] != 0)
dup2(tochild[0],0);
dup2(0,1);
dup2(0,2);
close(tochild[1]); /* Same as fromchild[0] */
}
void pipes_shutdown_child(fd)
int fd;
{
/* We close the parent->child writer channel */
shutdown(fd, 1 /* disable further send operations */);
}
#else /* not HAVE_SOCKETPAIR -- we have ordinary pipes then..
(someday we can add here SysV streams-pipes..) */
/*
* Life is not sweet and simple, but rather hard as we have only
* uni-directional FIFO-like pipes...
*/
int pipes_create(tochild, fromchild)
int tochild[2];
int fromchild[2];
{
int rc;
rc = epipe(tochild);
if (rc < 0) {
return rc;
}
rc = epipe(fromchild);
if (rc < 0) {
close(tochild[0]);
close(tochild[1]);
}
return rc;
}
void pipes_close_parent(tochild, fromchild)
int tochild[2];
int fromchild[2];
{
close(tochild[0]);
close(fromchild[1]);
}
void pipes_to_child_fds(tochild, fromchild)
int tochild[2];
int fromchild[2];
{
if (tochild[0] != 0) {
dup2(tochild[0], 0); /* STDIN channel */
close(tochild[0]);
}
if (fromchild[1] != 1) {
dup2(fromchild[1],1); /* STDOUT channel */
close(fromchild[1]);
}
dup2(1,2); /* STDERR channel */
}
void pipes_shutdown_child(fd)
int fd;
{
close(fd);
}
#endif
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