pipe.c

ソースコードを見る。

関数
pid_t	piped_child (char **command, int *f_in, int *f_out)
	Create a child connected to us via its stdin/stdout.
pid_t	local_child (int argc, char **argv, int *f_in, int *f_out, int(*child_main)(int, char *[]))
変数
int	am_sender
int	am_server
int	blocking_io
int	filesfrom_fd
mode_t	orig_umask
chmod_mode_struct *	chmod_modes

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関数

pid_t piped_child	(	char **	command,
		int *	f_in,
		int *	f_out
	)

Create a child connected to us via its stdin/stdout.

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.

pipe.c の 44 行で定義されています。

参照先 blocking_io・do_fork()・errno・fd_pair()・FERROR・orig_umask・print_child_argv()・rsyserr()・set_blocking()・verbose.

参照元 do_cmd().

{
        pid_t pid;
        int to_child_pipe[2];
        int from_child_pipe[2];

        if (verbose >= 2) {
                print_child_argv(command);
        }

        if (fd_pair(to_child_pipe) < 0 || fd_pair(from_child_pipe) < 0) {
                rsyserr(FERROR, errno, "pipe");
                exit_cleanup(RERR_IPC);
        }

        pid = do_fork();
        if (pid == -1) {
                rsyserr(FERROR, errno, "fork");
                exit_cleanup(RERR_IPC);
        }

        if (pid == 0) {
                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) {
                        rsyserr(FERROR, errno, "Failed to dup/close");
                        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 > 0)
                        set_blocking(STDOUT_FILENO);
                execvp(command[0], command);
                rsyserr(FERROR, errno, "Failed to exec %s", command[0]);
                exit_cleanup(RERR_IPC);
        }

        if (close(from_child_pipe[1]) < 0 || close(to_child_pipe[0]) < 0) {
                rsyserr(FERROR, errno, "Failed to close");
                exit_cleanup(RERR_IPC);
        }

        *f_in = from_child_pipe[0];
        *f_out = to_child_pipe[1];

        return pid;
}

pid_t local_child	(	int	argc,
		char **	argv,
		int *	f_in,
		int *	f_out,
		int(*)(int, char *[])	child_main
	)

pipe.c の 107 行で定義されています。

参照先 am_sender・am_server・child_main()・chmod_modes・do_fork()・errno・fd_pair()・FERROR・filesfrom_fd・rsyserr().

参照元 do_cmd().

{
        pid_t pid;
        int to_child_pipe[2];
        int from_child_pipe[2];

        /* The parent process is always the sender for a local rsync. */
        assert(am_sender);

        if (fd_pair(to_child_pipe) < 0 ||
            fd_pair(from_child_pipe) < 0) {
                rsyserr(FERROR, errno, "pipe");
                exit_cleanup(RERR_IPC);
        }

        pid = do_fork();
        if (pid == -1) {
                rsyserr(FERROR, errno, "fork");
                exit_cleanup(RERR_IPC);
        }

        if (pid == 0) {
                am_sender = 0;
                am_server = 1;
                filesfrom_fd = -1;
                chmod_modes = NULL; /* Let the sending side handle this. */

                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) {
                        rsyserr(FERROR, errno, "Failed to dup/close");
                        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]);
                child_main(argc, argv);
        }

        if (close(from_child_pipe[1]) < 0 ||
            close(to_child_pipe[0]) < 0) {
                rsyserr(FERROR, errno, "Failed to close");
                exit_cleanup(RERR_IPC);
        }

        *f_in = from_child_pipe[0];
        *f_out = to_child_pipe[1];

        return pid;
}

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変数

int am_sender

options.c の 76 行で定義されています。

int am_server

options.c の 75 行で定義されています。

int blocking_io

options.c の 114 行で定義されています。

int filesfrom_fd

options.c の 88 行で定義されています。

mode_t orig_umask

main.c の 65 行で定義されています。

struct chmod_mode_struct* chmod_modes

options.c の 174 行で定義されています。

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