eid.c

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/**
 * \addtogroup agent
 * @{
 */

/**
 * \file
 *
 * \author Wolf-Bastian Pöttner <poettner@ibr.cs.tu-bs.de>
 */

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

#include "contiki.h"
#include "logging.h"

#include "agent.h"
#include "sdnv.h"

#include "eid.h"

#define BUFFER_LENGTH 100

int eid_parse_host(char * buffer, uint8_t length, uint32_t * node_id)
{
        /* Do we have an ipn scheme? */
        if( strncmp(buffer, "ipn:", 4) != 0 ) {
                LOG(LOGD_DTN, LOG_AGENT, LOGL_WRN, "Unknown EID format %s", &buffer[4]);
                return -1;
        }

        /* Extract the node part of the EID */
        *node_id = atoi(&buffer[4]);

        return strlen(buffer);
}

int eid_parse_host_length(uint8_t * buffer, uint8_t length, uint32_t * node_id)
{
        uint32_t eid_length;
        int sdnv_length = 0;
        int ret = 0;

        /* Recover the EID length */
        sdnv_length = sdnv_decode(buffer, length, &eid_length);
        if (sdnv_length < 0) {
                LOG(LOGD_DTN, LOG_AGENT, LOGL_WRN, "Unknown EID format %s", &buffer[4]);
                return -1;
        }

        /* Parse the EID */
        ret = eid_parse_host((char *) &buffer[sdnv_length], length - sdnv_length, node_id);
        if( ret < 0 ) {
                LOG(LOGD_DTN, LOG_AGENT, LOGL_WRN, "Unknown EID format %s", &buffer[4]);
                return -1;
        }

        return sdnv_length + ret;
}

int eid_parse_full(char * buffer, uint8_t length, uint32_t * node_id, uint32_t * service_id)
{
        char * delimeter = NULL;
        int result;

        /* Do we have an ipn scheme? */
        if( strncmp(buffer, "ipn:", 4) != 0 ) {
                LOG(LOGD_DTN, LOG_AGENT, LOGL_WRN, "Unknown EID format %s", &buffer[4]);
                return -1;
        }

        /* Go and search for the . delimeter */
        delimeter = strchr(buffer, '.');
        if( delimeter == NULL ) {
                LOG(LOGD_DTN, LOG_AGENT, LOGL_WRN, "Unknown EID format %s", &buffer[4]);
                return -1;
        }

        /* Make this two seperate strings */
        *delimeter = 0;
        delimeter ++;

        /* Now parse host part */
        *node_id = atoi(&buffer[4]);

        /* And service part */
        *service_id = atoi(delimeter);

        result = strlen(buffer) + strlen(delimeter) + 1;

        /* Reconstruct the original string */
        *(delimeter-1) = '.';

        return result;
}


int eid_parse_full_length(uint8_t * buffer, uint8_t length, uint32_t * node_id, uint32_t * service_id)
{
        uint32_t eid_length;
        int sdnv_length = 0;
        int ret = 0;

        /* Recover the EID length */
        sdnv_length = sdnv_decode(buffer, length, &eid_length);
        if (sdnv_length < 0) {
                LOG(LOGD_DTN, LOG_AGENT, LOGL_WRN, "Unknown EID format %s", &buffer[4]);
                return -1;
        }

        ret = eid_parse_full((char *) &buffer[sdnv_length], length - sdnv_length, node_id, service_id);
        if( ret < 0 ) {
                LOG(LOGD_DTN, LOG_AGENT, LOGL_WRN, "Unknown EID format %s", &buffer[4]);
                return -1;
        }

        return sdnv_length + ret;
}

int eid_create_host(uint32_t node_id, char * buffer, uint8_t length)
{
        return sprintf(buffer, "ipn:%lu", node_id);
}

int eid_create_host_length(uint32_t node_id, uint8_t * buffer, uint8_t length)
{
        char string_buffer[BUFFER_LENGTH];
        int ret = 0;
        int eid_length = 0;

        /* Encode EID */
        eid_length = eid_create_host(node_id, string_buffer, BUFFER_LENGTH);
        if( eid_length < 0 ) {
                return eid_length;
        }

        /* Encode length of EID */
        ret = sdnv_encode(eid_length, (uint8_t *) buffer, length);
        if (ret < 0) {
                return -1;
        }

        /* Check if we have enough buffer left */
        if( length - ret < eid_length ) {
                return -1;
        }

        /* And then append the EID string */
        memcpy(buffer + ret, string_buffer, eid_length);

        return ret + eid_length;
}

int eid_create_full(uint32_t node_id, uint32_t service_id, char * buffer, uint8_t length)
{
        return sprintf(buffer, "ipn:%lu.%lu", node_id, service_id);
}

int eid_create_full_length(uint32_t node_id, uint32_t service_id, uint8_t * buffer, uint8_t length)
{
        char string_buffer[BUFFER_LENGTH];
        int ret = 0;
        int eid_length = 0;

        /* Encode EID */
        eid_length = eid_create_full(node_id, service_id, string_buffer, BUFFER_LENGTH);
        if( eid_length < 0 ) {
                return eid_length;
        }

        /* Encode length of EID */
        ret = sdnv_encode(eid_length, (uint8_t *) buffer, length);
        if (ret < 0) {
                return -1;
        }

        /* Check if we have enough buffer left */
        if( length - ret < eid_length ) {
                return -1;
        }

        /* And then append the EID string */
        memcpy(buffer + ret, string_buffer, eid_length);

        return ret + eid_length;
}