+/****************************************************************************
+Set a fd into nonblocking mode
+****************************************************************************/
+void set_nonblocking(int fd)
+{
+ int val;
+
+ if((val = fcntl(fd, F_GETFL, 0)) == -1)
+ return;
+ if (!(val & NONBLOCK_FLAG)) {
+ val |= NONBLOCK_FLAG;
+ fcntl(fd, F_SETFL, val);
+ }
+}
+
+/****************************************************************************
+Set a fd into blocking mode
+****************************************************************************/
+void set_blocking(int fd)
+{
+ int val;
+
+ if((val = fcntl(fd, F_GETFL, 0)) == -1)
+ return;
+ if (val & NONBLOCK_FLAG) {
+ val &= ~NONBLOCK_FLAG;
+ fcntl(fd, F_SETFL, val);
+ }
+}
+
+
+/* create a file descriptor pair - like pipe() but use socketpair if
+ possible (because of blocking issues on pipes)
+
+ always set non-blocking
+ */
+int fd_pair(int fd[2])
+{
+ int ret;
+
+#if HAVE_SOCKETPAIR
+ ret = socketpair(AF_UNIX, SOCK_STREAM, 0, fd);
+#else
+ ret = pipe(fd);
+#endif
+
+ if (ret == 0) {
+ set_nonblocking(fd[0]);
+ set_nonblocking(fd[1]);
+ }
+
+ return ret;
+}
+
+
+static void print_child_argv(char **cmd)
+{
+ rprintf(FINFO, "opening connection using ");
+ for (; *cmd; cmd++) {
+ /* Look for characters that ought to be quoted. This
+ * is not a great quoting algorithm, but it's
+ * sufficient for a log message. */
+ if (strspn(*cmd, "abcdefghijklmnopqrstuvwxyz"
+ "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ "0123456789"
+ ",.-_=+@/") != strlen(*cmd)) {
+ rprintf(FINFO, "\"%s\" ", *cmd);
+ } else {
+ rprintf(FINFO, "%s ", *cmd);
+ }
+ }
+ rprintf(FINFO, "\n");
+}
+
+
+/* this is derived from CVS code
+
+ note that in the child STDIN is set to blocking and STDOUT
+ is set to non-blocking. This is necessary as rsh relies on stdin being blocking
+ and ssh relies on stdout being non-blocking
+
+ if blocking_io is set then use blocking io on both fds. That can be
+ used to cope with badly broken rsh implementations like the one on
+ solaris.
+ */
+pid_t piped_child(char **command, int *f_in, int *f_out)
+{
+ pid_t pid;
+ int to_child_pipe[2];
+ int from_child_pipe[2];
+ extern int blocking_io;
+
+ if (verbose >= 2) {
+ print_child_argv(command);
+ }
+
+ if (fd_pair(to_child_pipe) < 0 || fd_pair(from_child_pipe) < 0) {
+ rprintf(FERROR, "pipe: %s\n", strerror(errno));
+ exit_cleanup(RERR_IPC);
+ }
+
+
+ pid = do_fork();
+ if (pid == -1) {
+ rprintf(FERROR, "fork: %s\n", strerror(errno));
+ exit_cleanup(RERR_IPC);
+ }
+
+ if (pid == 0) {
+ extern int orig_umask;
+ if (dup2(to_child_pipe[0], STDIN_FILENO) < 0 ||
+ close(to_child_pipe[1]) < 0 ||
+ close(from_child_pipe[0]) < 0 ||
+ dup2(from_child_pipe[1], STDOUT_FILENO) < 0) {
+ rprintf(FERROR, "Failed to dup/close : %s\n",
+ strerror(errno));
+ exit_cleanup(RERR_IPC);
+ }
+ if (to_child_pipe[0] != STDIN_FILENO)
+ close(to_child_pipe[0]);
+ if (from_child_pipe[1] != STDOUT_FILENO)
+ close(from_child_pipe[1]);
+ umask(orig_umask);
+ set_blocking(STDIN_FILENO);
+ if (blocking_io) {
+ set_blocking(STDOUT_FILENO);
+ }
+ execvp(command[0], command);
+ rprintf(FERROR, "Failed to exec %s : %s\n",
+ command[0], strerror(errno));
+ exit_cleanup(RERR_IPC);
+ }
+
+ if (close(from_child_pipe[1]) < 0 || close(to_child_pipe[0]) < 0) {
+ rprintf(FERROR, "Failed to close : %s\n", strerror(errno));
+ exit_cleanup(RERR_IPC);
+ }