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/* $Id: child.c,v 1.146 2008/09/07 21:51:41 nicm Exp $ */
/*
* Copyright (c) 2006 Nicholas Marriott <nicm@users.sourceforge.net>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
* IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
* OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <unistd.h>
#include "fdm.h"
void child_sighandler(int);
void
child_sighandler(int sig)
{
switch (sig) {
#ifdef SIGINFO
case SIGINFO:
#endif
case SIGUSR1:
sigusr1 = 1;
break;
case SIGTERM:
cleanup_purge();
_exit(1);
}
}
int
child_fork(void)
{
pid_t pid;
struct sigaction act;
switch (pid = fork()) {
case -1:
fatal("fork failed");
case 0:
cleanup_flush();
sigemptyset(&act.sa_mask);
#ifdef SIGINFO
sigaddset(&act.sa_mask, SIGINFO);
#endif
sigaddset(&act.sa_mask, SIGUSR1);
sigaddset(&act.sa_mask, SIGINT);
sigaddset(&act.sa_mask, SIGTERM);
act.sa_flags = SA_RESTART;
act.sa_handler = SIG_IGN;
if (sigaction(SIGINT, &act, NULL) < 0)
fatal("sigaction failed");
act.sa_handler = child_sighandler;
#ifdef SIGINFO
if (sigaction(SIGINFO, &act, NULL) < 0)
fatal("sigaction failed");
#endif
if (sigaction(SIGUSR1, &act, NULL) < 0)
fatal("sigaction failed");
if (sigaction(SIGTERM, &act, NULL) < 0)
fatal("sigaction failed");
return (0);
default:
return (pid);
}
}
__dead void
child_exit(int status)
{
cleanup_check();
_exit(status);
}
struct child *
child_start(struct children *children, uid_t uid, gid_t gid,
int (*start)(struct child *, struct io *),
int (*msg)(struct child *, struct msg *, struct msgbuf *),
void *data, struct child *parent)
{
struct child *child, *childp;
int fds[2], n;
u_int i;
struct io *io;
if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, fds) != 0)
fatal("socketpair failed");
child = xcalloc(1, sizeof *child);
child->io = io_create(fds[0], NULL, IO_CRLF);
child->data = data;
child->msg = msg;
child->parent = parent;
if ((child->pid = child_fork()) == 0) {
for (i = 0; i < ARRAY_LENGTH(children); i++) {
childp = ARRAY_ITEM(children, i);
io_close(childp->io);
io_free(childp->io);
}
io_close(child->io);
io_free(child->io);
if (geteuid() == 0)
dropto(uid, gid);
io = io_create(fds[1], NULL, IO_LF);
n = start(child, io);
io_close(io);
io_free(io);
#ifdef PROFILE
/*
* We want to use _exit rather than exit in the child process,
* and it doesn't run atexit handlers, so run _mcleanup
* manually to force the profiler to dump its statistics.
*
* This is icky but it works, and is only for profiling.
*/
extern void _mcleanup(void);
_mcleanup();
#endif
child_exit(n);
}
close(fds[1]);
ARRAY_ADD(children, child);
return (child);
}
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