source: mainline/uspace/srv/net/structures/packet/packet_client.c@ aadf01e

/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/** @addtogroup packet
 *  @{
 */

/** @file
 *  Packet client implementation.
 */

#include <errno.h>
#include <mem.h>
#include <unistd.h>
//#include <stdio.h>

#include <sys/mman.h>

#include "../../messages.h"

#include "packet.h"
#include "packet_header.h"
#include "packet_client.h"

int packet_copy_data(packet_t packet, const void * data, size_t length){
        if(! packet_is_valid(packet)){
                return EINVAL;
        }
        if(packet->data_start + length >= packet->length){
                return ENOMEM;
        }
        memcpy((void *) packet + packet->data_start, data, length);
        if(packet->data_start + length > packet->data_end){
                packet->data_end = packet->data_start + length;
        }
        return EOK;
}

void * packet_prefix(packet_t packet, size_t length){
        if((! packet_is_valid(packet)) || (packet->data_start - sizeof(struct packet) - 2 * (packet->dest_addr - packet->src_addr) < length)){
                return NULL;
        }
        packet->data_start -= length;
        return (void *) packet + packet->data_start;
}

void * packet_suffix(packet_t packet, size_t length){
        if((! packet_is_valid(packet)) || (packet->data_end + length >= packet->length)){
                return NULL;
        }
        packet->data_end += length;
        return (void *) packet + packet->data_end - length;
}

int packet_trim(packet_t packet, size_t prefix, size_t suffix){
        if(! packet_is_valid(packet)){
                return EINVAL;
        }
        if(prefix + suffix > PACKET_DATA_LENGTH(packet)){
                return ENOMEM;
        }
        packet->data_start += prefix;
        packet->data_end -= suffix;
        return EOK;
}

packet_id_t packet_get_id(const packet_t packet){
        return packet_is_valid(packet) ? packet->packet_id : 0;
}

int packet_get_addr(const packet_t packet, uint8_t ** src, uint8_t ** dest){
        if(! packet_is_valid(packet)){
                return EINVAL;
        }
        if(! packet->addr_len){
                return 0;
        }
        if(src){
                *src = (void *) packet + packet->src_addr;
        }
        if(dest){
                *dest = (void *) packet + packet->dest_addr;
        }
        return packet->addr_len;
}

size_t packet_get_data_length(const packet_t packet){
        if(! packet_is_valid(packet)){
                return 0;
        }
        return PACKET_DATA_LENGTH(packet);
}

void * packet_get_data(const packet_t packet){
        if(! packet_is_valid(packet)){
                return NULL;
        }
        return (void *) packet + packet->data_start;
}

int packet_set_addr(packet_t packet, const uint8_t * src, const uint8_t * dest, size_t addr_len){
        size_t padding;
        size_t allocated;

        if(! packet_is_valid(packet)){
                return EINVAL;
        }
        allocated = PACKET_MAX_ADDRESS_LENGTH(packet);
        if(allocated < addr_len){
                return ENOMEM;
        }
        padding = allocated - addr_len;
        packet->addr_len = addr_len;
        if(src){
                memcpy((void *) packet + packet->src_addr, src, addr_len);
                if(padding){
                        bzero((void *) packet + packet->src_addr + addr_len, padding);
                }
        }else{
                bzero((void *) packet + packet->src_addr, allocated);
        }
        if(dest){
                memcpy((void *) packet + packet->dest_addr, dest, addr_len);
                if(padding){
                        bzero((void *) packet + packet->dest_addr + addr_len, padding);
                }
        }else{
                bzero((void *) packet + packet->dest_addr, allocated);
        }
        return EOK;
}

packet_t packet_get_copy(int phone, packet_t packet){
        packet_t copy;
        uint8_t * src;
        uint8_t * dest;
        size_t addrlen;

        if(! packet_is_valid(packet)){
                return NULL;
        }
        // get a new packet
        copy = packet_get_4(phone, PACKET_DATA_LENGTH(packet), PACKET_MAX_ADDRESS_LENGTH(packet), packet->max_prefix, PACKET_MIN_SUFFIX(packet));
        if(! copy){
                return NULL;
        }
        // get addresses
        addrlen = packet_get_addr(packet, &src, &dest);
        // copy data
        if((packet_copy_data(copy, packet_get_data(packet), PACKET_DATA_LENGTH(packet)) == EOK)
        // copy addresses if present
                && ((addrlen <= 0) || (packet_set_addr(copy, src, dest, addrlen) == EOK))){
                copy->order = packet->order;
                copy->metric = packet->metric;
                return copy;
        }else{
                pq_release(phone, copy->packet_id);
                return NULL;
        }
}

/** @}
 */