send_buffer.c

#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#include "buffer.h"
#include "packet.h"

static buffer_t buffer;

int send_buffer_init()
{
    return buffer_init(&buffer);
}

int send_packet_buffer_write(packet_t *packet)
{
    return buffer_write_packet(&buffer, packet);
}

int send_packet_buffer_read(packet_t *packet)
{
    return buffer_read_packet(&buffer, packet);
}

int send_buffer_write(char *data, int len)
{
    packet_t packet;
    int size = 0;
    int seqnum;
    int boundary;
    int retval;
    char *buffer;

    size = len;
    retval = len;
    seqnum = 2142894844;  /* TODO: generate random number */
    buffer = data;
    boundary = PACKET_BOUNDARY_START;

    while (len > 0) {
        size = (len > PACKET_DATA_SIZE) ? PACKET_DATA_SIZE : len;
        len -= PACKET_DATA_SIZE;
        boundary |= (len > 0) ? PACKET_BOUNDARY_NONE : PACKET_BOUNDARY_END;

        packet_clear_header (packet);
        packet_set_data     (packet);
        packet_set_seqnum   (packet, seqnum++);
        packet_set_boundary (packet, boundary);
        packet_set_order    (packet, 1);
        packet_set_msgnum   (packet, 1);
        packet_set_timestamp(packet, 0x0000051c); /* TODO: calculate time */
        packet_set_id       (packet, 0x08c42c74); /* TODO: generate an id */

        packet_new(&packet, buffer, size);
        send_packet_buffer_write(&packet);

        buffer += size;
        boundary = PACKET_BOUNDARY_NONE;
    }

    packet_clear_header (packet);
    packet_set_ctrl     (packet);
    packet_set_type     (packet, PACKET_TYPE_ACK);
    packet_set_timestamp(packet, 0x0000051c); /* TODO: calculate time */
    packet_set_id       (packet, 0x08c42c74); /* TODO: generate an id */

    packet_new(&packet, NULL, 0);
    send_packet_buffer_write(&packet);

    return retval;
}

int64_t send_file_buffer_write(int fd, int64_t offset, int64_t size, int64_t blocksize)
{

    packet_t packet;

    int retval;
    int seqnum;
    char buffer[PACKET_DATA_SIZE];
    int boundary;
    int len;
    int bytes_to_read;

    retval 		= 0;
    seqnum 		= 2142894844;  /* TODO: generate random number */
    boundary 	= PACKET_BOUNDARY_START;	

    if (fd < 0) return -1;

    while (size > 0)
    {
        bytes_to_read = (size > PACKET_DATA_SIZE) ? PACKET_DATA_SIZE : size;
        len = pread(fd, buffer, bytes_to_read, offset);
        if (len < 0) break;
        retval += len;
        size -= len;

        /* if bytes read is less than the desired, then its EOF */
        if (len < bytes_to_read) {
            size = 0;
        }

        boundary |= (size > 0) ? PACKET_BOUNDARY_NONE : PACKET_BOUNDARY_END;

        packet_clear_header (packet);
        packet_set_data     (packet);
        packet_set_seqnum   (packet, seqnum++);
        packet_set_boundary (packet, boundary);
        packet_set_order    (packet, 1);
        packet_set_msgnum   (packet, 1);
        packet_set_timestamp(packet, 0x0000051c); /* TODO: calculate time */
        packet_set_id       (packet, 0x08c42c74); /* TODO: generate an id */

        packet_new(&packet, buffer, len);
        send_packet_buffer_write(&packet);

        boundary = PACKET_BOUNDARY_NONE;

        offset += len;
    }

    packet_clear_header (packet);
    packet_set_ctrl     (packet);
    packet_set_type     (packet, PACKET_TYPE_ACK);
    packet_set_timestamp(packet, 0x0000051c); /* TODO: calculate time */
    packet_set_id       (packet, 0x08c42c74); /* TODO: generate an id */

    packet_new(&packet, NULL, 0);
    send_packet_buffer_write(&packet);

    return retval;
}