/*

 * Copyright (C) Igor Sysoev

 * Copyright (C) NGINX, Inc.

 */

#include <nxt_main.h>

#include <nxt_socket_msg.h>

/*

 * SOCK_SEQPACKET protocol is supported for AF_UNIX in Solaris 8 X/Open

 * sockets, Linux 2.6.4, FreeBSD 9.0, NetBSD 6.0, and OpenBSD 5.0.

 */

/* SOCK_SEQPACKET is disabled to test SOCK_DGRAM on all platforms. */

#if (0 || NXT_HAVE_AF_UNIX_SOCK_SEQPACKET)

#define NXT_UNIX_SOCKET  SOCK_SEQPACKET

#else

#define NXT_UNIX_SOCKET  SOCK_DGRAM

#endif

nxt_int_t

nxt_socketpair_create(nxt_task_t *task, nxt_socket_t *pair)

{

    if (nxt_slow_path(socketpair(AF_UNIX, NXT_UNIX_SOCKET, 0, pair) != 0)) {

        nxt_alert(task, "socketpair() failed %E", nxt_errno);

        return NXT_ERROR;

    }

    nxt_debug(task, "socketpair(): %d:%d", pair[0], pair[1]);

    if (nxt_slow_path(nxt_socket_nonblocking(task, pair[0]) != NXT_OK)) {

        goto fail;

    }

    if (nxt_slow_path(fcntl(pair[0], F_SETFD, FD_CLOEXEC) == -1)) {

        goto fail;

    }

    if (nxt_slow_path(nxt_socket_nonblocking(task, pair[1]) != NXT_OK)) {

        goto fail;

    }

    if (nxt_slow_path(fcntl(pair[1], F_SETFD, FD_CLOEXEC) == -1)) {

        goto fail;

    }

#if NXT_HAVE_SOCKOPT_SO_PASSCRED

    int  enable_creds = 1;

    if (nxt_slow_path(setsockopt(pair[0], SOL_SOCKET, SO_PASSCRED,

                      &enable_creds, sizeof(enable_creds)) == -1))

    {

        nxt_alert(task, "failed to set SO_PASSCRED %E", nxt_errno);

        goto fail;

    }

    if (nxt_slow_path(setsockopt(pair[1], SOL_SOCKET, SO_PASSCRED,

                      &enable_creds, sizeof(enable_creds)) == -1))

    {

        nxt_alert(task, "failed to set SO_PASSCRED %E", nxt_errno);

        goto fail;

    }

#endif

    return NXT_OK;

fail:

    nxt_socketpair_close(task, pair);

    return NXT_ERROR;

}

void

nxt_socketpair_close(nxt_task_t *task, nxt_socket_t *pair)

{

    nxt_socket_close(task, pair[0]);

    nxt_socket_close(task, pair[1]);

}

ssize_t

nxt_socketpair_send(nxt_fd_event_t *ev, nxt_fd_t *fd, nxt_iobuf_t *iob,

    nxt_uint_t niob)

{

    ssize_t         n;

    nxt_err_t       err;

    nxt_send_oob_t  oob;

    nxt_socket_msg_oob_init(&oob, fd);

    for ( ;; ) {

        n = nxt_sendmsg(ev->fd, iob, niob, &oob);

        err = (n == -1) ? nxt_socket_errno : 0;

        nxt_debug(ev->task, "sendmsg(%d, %FD, %FD, %ui): %z", ev->fd, fd[0],

                  fd[1], niob, n);

        if (n > 0) {

            return n;

        }

        /* n == -1 */

        switch (err) {

        case NXT_EAGAIN:

            nxt_debug(ev->task, "sendmsg(%d) not ready", ev->fd);

            break;

        /*

         * Returned (at least on OSX) when trying to send many small messages.

         */

        case NXT_ENOBUFS:

            nxt_debug(ev->task, "sendmsg(%d) no buffers", ev->fd);

            break;

        case NXT_EINTR:

            nxt_debug(ev->task, "sendmsg(%d) interrupted", ev->fd);

            continue;

        default:

            nxt_alert(ev->task, "sendmsg(%d, %FD, %FD, %ui) failed %E",

                      ev->fd, fd[0], fd[1], niob, err);

            return NXT_ERROR;

        }

        ev->write_ready = 0;

        return NXT_AGAIN;

    }

}

ssize_t

nxt_socketpair_recv(nxt_fd_event_t *ev, nxt_iobuf_t *iob, nxt_uint_t niob,

    void *oob)

{

    ssize_t    n;

    nxt_err_t  err;

    for ( ;; ) {

        n = nxt_recvmsg(ev->fd, iob, niob, oob);

        err = (n == -1) ? nxt_socket_errno : 0;

        nxt_debug(ev->task, "recvmsg(%d, %ui, %uz): %z",

                  ev->fd, niob, ((nxt_recv_oob_t *) oob)->size, n);

        if (n > 0) {

            return n;

        }

        if (n == 0) {

            ev->closed = 1;

            ev->read_ready = 0;

            return n;

        }

        /* n == -1 */

        switch (err) {

        case NXT_EAGAIN:

            nxt_debug(ev->task, "recvmsg(%d) not ready", ev->fd);

            ev->read_ready = 0;

            return NXT_AGAIN;

        case NXT_EINTR:

            nxt_debug(ev->task, "recvmsg(%d) interrupted", ev->fd);

            continue;

        default:

            nxt_alert(ev->task, "recvmsg(%d, %ui) failed %E",

                      ev->fd, niob, err);

            return NXT_ERROR;

        }

    }

}