graphene/LibOS/shim/src/sys/shim_pipe.c

/* -*- mode:c; c-file-style:"k&r"; c-basic-offset: 4; tab-width:4; indent-tabs-mode:nil; mode:auto-fill; fill-column:78; -*- */
/* vim: set ts=4 sw=4 et tw=78 fo=cqt wm=0: */

/* Copyright (C) 2014 OSCAR lab, Stony Brook University
   This file is part of Graphene Library OS.

   Graphene Library OS is free software: you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation, either version 3 of the
   License, or (at your option) any later version.

   Graphene Library OS is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/*
 * shim_pipe.c
 *
 * Implementation of system call "pipe", "pipe2" and "socketpair".
 */

#include <shim_internal.h>
#include <shim_utils.h>
#include <shim_table.h>
#include <shim_handle.h>
#include <shim_fs.h>

#include <pal.h>
#include <pal_error.h>

#include <errno.h>
#include <fcntl.h>

int create_pipes (IDTYPE * pipeid, PAL_HANDLE * srv, PAL_HANDLE * cli,
                  struct shim_qstr * qstr, int flags)
{
    PAL_HANDLE hdl0 = NULL, hdl1 = NULL, hdl2 = NULL;
    int ret = 0;
    char * uri = __alloca(PIPE_URI_SIZE);

    if ((ret = create_pipe(pipeid, uri, PIPE_URI_SIZE, &hdl0,
                           qstr)) < 0) {
        debug("pipe creation failure\n");
        return ret;
    }

    if (!(hdl2 = DkStreamOpen(uri, 0, 0, 0,
                              flags & O_NONBLOCK))) {
        ret = -PAL_ERRNO;
        debug("pipe connection failure\n");
        goto err;
    }

    if (!(hdl1 = DkStreamWaitForClient(hdl0))) {
        ret = -PAL_ERRNO;
        debug("pipe acception failure\n");
        goto err;
    }

    DkStreamDelete(hdl0, 0);
    DkObjectClose(hdl0);
    *srv = hdl1;
    *cli = hdl2;
    return 0;
err:
    if (hdl1)
        DkObjectClose(hdl1);
    if (hdl2)
        DkObjectClose(hdl2);
    DkStreamDelete(hdl0, 0);
    DkObjectClose(hdl0);
    return ret;
}

int shim_do_pipe2 (int * filedes, int flags)
{
    if (!filedes)
        return -EINVAL;

    int ret = 0;

    struct shim_handle * hdl1 = get_new_handle();
    struct shim_handle * hdl2 = get_new_handle();

    if (!hdl1 || !hdl2) {
        ret = -ENOMEM;
        goto out;
    }

    hdl1->type       = TYPE_PIPE;
    set_handle_fs(hdl1, &pipe_builtin_fs);
    hdl1->acc_mode   = MAY_READ;

    hdl2->type       = TYPE_PIPE;
    set_handle_fs(hdl2, &pipe_builtin_fs);
    hdl2->acc_mode   = MAY_WRITE;

    if ((ret = create_pipes(&hdl1->info.pipe.pipeid,
                            &hdl1->pal_handle, &hdl2->pal_handle,
                            &hdl1->uri, flags)) < 0)
        goto out;

    qstrcopy(&hdl2->uri, &hdl2->uri);

    flags = flags & O_CLOEXEC ? FD_CLOEXEC : 0;
    int vfd1 = set_new_fd_handle(hdl1, flags, NULL);
    int vfd2 = set_new_fd_handle(hdl2, flags, NULL);

    if (vfd1 < 0 || vfd2 < 0) {
        if (vfd1 >= 0) {
            struct shim_handle * tmp = detach_fd_handle(vfd1, NULL, NULL);
            if (tmp)
                close_handle(tmp);
        }
        if (vfd2 >= 0) {
            struct shim_handle * tmp = detach_fd_handle(vfd2, NULL, NULL);
            if (tmp)
                close_handle(tmp);
        }
        goto out;
    }

    filedes[0] = vfd1;
    filedes[1] = vfd2;
out:
    if (hdl1)
        put_handle(hdl1);
    if (hdl2)
        put_handle(hdl2);
    return ret;
}

int shim_do_pipe (int * filedes)
{
    return shim_do_pipe2(filedes, 0);
}

int shim_do_socketpair (int domain, int type, int protocol, int * sv)
{
    if (domain != AF_UNIX)
        return -EAFNOSUPPORT;

    if (type != SOCK_STREAM)
        return -EPROTONOSUPPORT;

    if (!sv)
        return -EINVAL;

    int ret = 0;
    struct shim_handle * hdl1 = get_new_handle();
    struct shim_handle * hdl2 = get_new_handle();

    if (!hdl1 || !hdl2) {
        ret = -ENOMEM;
        goto out;
    }

    struct shim_sock_handle * sock1 = &hdl1->info.sock;
    struct shim_sock_handle * sock2 = &hdl2->info.sock;

    hdl1->type          = TYPE_SOCK;
    set_handle_fs(hdl1, &socket_builtin_fs);
    hdl1->acc_mode      = MAY_READ|MAY_WRITE;
    sock1->domain       = domain;
    sock1->sock_type    = type & ~(SOCK_NONBLOCK|SOCK_CLOEXEC);
    sock1->protocol     = protocol;
    sock1->sock_state   = SOCK_ACCEPTED;

    hdl2->type          = TYPE_SOCK;
    set_handle_fs(hdl2, &socket_builtin_fs);
    hdl2->acc_mode      = MAY_READ|MAY_WRITE;
    sock2->domain       = domain;
    sock2->sock_type    = type & ~(SOCK_NONBLOCK|SOCK_CLOEXEC);
    sock2->protocol     = protocol;
    sock2->sock_state   = SOCK_CONNECTED;

    if ((ret = create_pipes(&sock1->addr.un.pipeid, &hdl1->pal_handle,
                            &hdl2->pal_handle, &hdl1->uri,
                            type & SOCK_NONBLOCK ? O_NONBLOCK : 0)) < 0)
        goto out;

    sock2->addr.un.pipeid = sock1->addr.un.pipeid;
    qstrcopy(&hdl2->uri, &hdl1->uri);

    int flags = type & SOCK_CLOEXEC ? FD_CLOEXEC : 0;
    int vfd1 = set_new_fd_handle(hdl1, flags, NULL);
    int vfd2 = set_new_fd_handle(hdl2, flags, NULL);

    if (vfd1 < 0 || vfd2 < 0) {
        if (vfd1 >= 0) {
            struct shim_handle * tmp = detach_fd_handle(vfd1, NULL, NULL);
            if (tmp)
                close_handle(tmp);
        }
        if (vfd2 >= 0) {
            struct shim_handle * tmp = detach_fd_handle(vfd2, NULL, NULL);
            if (tmp)
                close_handle(tmp);
        }
        goto out;
    }

    sv[0] = vfd1;
    sv[1] = vfd2;
out:
    if (hdl1)
        put_handle(hdl1);
    if (hdl2)
        put_handle(hdl2);
    return ret;
}