*/
#include "includes.h"
-RCSID("$OpenBSD: serverloop.c,v 1.86 2001/12/19 07:18:56 deraadt Exp $");
+RCSID("$OpenBSD: serverloop.c,v 1.87 2001/12/19 16:09:39 markus Exp $");
#include "xmalloc.h"
#include "packet.h"
/* prototypes */
static void server_init_dispatch(void);
+/*
+ * we write to this pipe if a SIGCHLD is caught in order to avoid
+ * the race between select() and child_terminated
+ */
+static int notify_pipe[2];
+static void
+notify_setup(void)
+{
+ if (pipe(notify_pipe) < 0) {
+ error("pipe(notify_pipe) failed %s", strerror(errno));
+ } else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) ||
+ (fcntl(notify_pipe[1], F_SETFD, 1) == -1)) {
+ error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno));
+ close(notify_pipe[0]);
+ close(notify_pipe[1]);
+ } else {
+ set_nonblock(notify_pipe[0]);
+ set_nonblock(notify_pipe[1]);
+ return;
+ }
+ notify_pipe[0] = -1; /* read end */
+ notify_pipe[1] = -1; /* write end */
+}
+static void
+notify_parent(void)
+{
+ if (notify_pipe[1] != -1)
+ write(notify_pipe[1], "", 1);
+}
+static void
+notify_prepare(fd_set *readset)
+{
+ if (notify_pipe[0] != -1)
+ FD_SET(notify_pipe[0], readset);
+}
+static void
+notify_done(fd_set *readset)
+{
+ char c;
+
+ if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset))
+ while (read(notify_pipe[0], &c, 1) != -1)
+ debug2("notify_done: reading");
+}
+
static void
sigchld_handler(int sig)
{
debug("Received SIGCHLD.");
child_terminated = 1;
mysignal(SIGCHLD, sigchld_handler);
+ notify_parent();
errno = save_errno;
}
if (fdin != -1 && buffer_len(&stdin_buffer) > 0)
FD_SET(fdin, *writesetp);
}
+ notify_prepare(*readsetp);
/*
* If we have buffered packet data going to the client, mark that
error("select: %.100s", strerror(errno));
} else if (ret == 0 && client_alive_scheduled)
client_alive_check();
+
+ notify_done(*readsetp);
}
/*
connection_in = packet_get_connection_in();
connection_out = packet_get_connection_out();
+ notify_setup();
+
previous_stdout_buffer_bytes = 0;
/* Set approximate I/O buffer size. */
max_fd = MAX(max_fd, fdin);
max_fd = MAX(max_fd, fdout);
max_fd = MAX(max_fd, fderr);
+ max_fd = MAX(max_fd, notify_pipe[0]);
/* Sleep in select() until we can do something. */
wait_until_can_do_something(&readset, &writeset, &max_fd,
connection_in = packet_get_connection_in();
connection_out = packet_get_connection_out();
+ notify_setup();
+
max_fd = MAX(connection_in, connection_out);
+ max_fd = MAX(max_fd, notify_pipe[0]);
+
xxx_authctxt = authctxt;
server_init_dispatch();