tap-ctl-info.c

/*
 * Copyright (c) 2016, Citrix Systems, Inc.
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * 
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. Neither the name of the copyright holder nor the names of its 
 *     contributors may be used to endorse or promote products derived from 
 *     this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "debug.h"
#include "tap-ctl.h"

int tap_ctl_info(pid_t pid, unsigned long long *sectors,
		unsigned int *sector_size, unsigned int *info, const int minor)
{
    tapdisk_message_t message;
    int err;

    ASSERT(sectors);
    ASSERT(sector_size);
    ASSERT(info);

    memset(&message, 0, sizeof(message));
    message.type = TAPDISK_MESSAGE_DISK_INFO;
	message.cookie = minor;

    err = tap_ctl_connect_send_and_receive(pid, &message, NULL);
    if (err) {
        EPRINTF("failed to get info from tapdisk %d: %s\n", pid,
                strerror(-err));
        return err;
    }

    if (TAPDISK_MESSAGE_DISK_INFO_RSP == message.type) {
        *sectors = message.u.image.sectors;
        *sector_size = message.u.image.sector_size;
        *info = message.u.image.info;
        return 0;
    } else if (TAPDISK_MESSAGE_ERROR == message.type) {
       return -message.u.response.error;
    } else {
        EPRINTF("unexpected reply %d\n", message.type);
        return -EINVAL;
    }
}