inetq/inetq.c

Requests an URL from the Internet and transfers the HTML source code to the serial device.

Your local Ethernet network must provide Internet access. Connect the RS232 port of the Ethernut with a free COM port of your PC and run a terminal emulator at 115200 Baud.

If your local network does not support DHCP, it may be required to modify the MY_IP, MY_MASK and MY_GATE below.

This sample demonstrates DNS query and default route usage.

#define DNSSERVERIP     "192.168.192.2"
#define INETSERVER  "www.kornet.net"
#define INETSERVERPORT  80
#define INETURL         "/"
#define MY_MAC          {0x00,0x06,0x98,0x20,0x00,0x00}
#define MY_IP           "192.168.192.100"
#define MY_MASK         "255.255.255.0"
#define MY_GATE         "192.168.192.3"

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

#include <dev/board.h>

#include <sys/heap.h>
#include <sys/thread.h>
#include <sys/timer.h>
#include <sys/socket.h>
#include <sys/confnet.h>

#include <arpa/inet.h>
#include <net/route.h>
#include <netdb.h>

#include <pro/dhcp.h>

static char buff[1024];
static u_char my_mac[] = MY_MAC;

/*
 * Main application routine. 
 *
 */
int main(void)
{
    u_long baud = 115200;
    TCPSOCKET *sock;
    FILE *stream;
    u_long rip;
    u_long ip_addr;
    int bite;
    size_t rc;
    size_t len;
    u_long start_time;
    u_long total_bytes;

    /*
     * Initialize the uart device.
     */
    NutRegisterDevice(&DEV_DEBUG, 0, 0);
    freopen(DEV_DEBUG_NAME, "w", stdout);
    _ioctl(_fileno(stdout), UART_SETSPEED, &baud);
    puts("\nInetQuery 1.0");

    /*
     * Register Realtek controller at address 8300 hex and interrupt 5.
     */
    puts("Configuring Ethernet interface");
    NutRegisterDevice(&DEV_ETHER, 0, 0);

    /*
     * Try DHCP. First use MAC from EEPROM.
     */
    if (NutDhcpIfConfig("eth0", 0, 60000) && NutDhcpIfConfig("eth0", my_mac, 60000)) {
        /*
         * No DHCP server available. Use hard coded values.
         */
        ip_addr = inet_addr(MY_IP);
        NutNetIfConfig("eth0", my_mac, ip_addr, inet_addr(MY_MASK));
        NutIpRouteAdd(0, 0, inet_addr(MY_GATE), &DEV_ETHER);
        NutDnsConfig(0, 0, inet_addr(DNSSERVERIP));
    } else
        ip_addr = confnet.cdn_ip_addr;
    printf("%s ready\n", inet_ntoa(ip_addr));


    /*
     * Resolve hostname using DNS.
     */
    if ((rip = NutDnsGetHostByName(INETSERVER)) != 0) {

        /*
         * Let's try a stdio stream first.
         */
        if ((sock = NutTcpCreateSocket()) != 0) {

            /*
             * Connect a HTTP server in the Internet.
             */
            printf("Connecting %s:%u\r\n", inet_ntoa(rip), INETSERVERPORT);
            if (NutTcpConnect(sock, rip, INETSERVERPORT) == 0) {

                /*
                 * Assign a stream to our connected socket.
                 */
                if ((stream = _fdopen((int) sock, "r+b")) != 0) {
                    /*
                     * Send HTTP request to the server.
                     */
                    fprintf(stream, "GET %s HTTP/1.0\r\n", INETURL);
                    fputs("User-Agent: Ethernut [en] (NutOS)\r\n", stream);
                    fputs("\r\n", stream);
                    fflush(stream);

                    /*
                     * Init measure values.
                     */
                    start_time = NutGetTickCount();
                    total_bytes = 0;

                    /*
                     * Read server response and send it to the UART.
                     */
                    while (fgets(buff, sizeof(buff), stream)) {
                        puts(buff);
                        total_bytes += strlen(buff);
                    }
                    printf("Transfered %lu bytes in %lu seconds\n", total_bytes, (NutGetTickCount() - start_time) / 16UL);
                    fclose(stream);
                } else
                    puts("Creating stream device failed");

            } else {
                printf("Bad news, %s refuses the connection.\n", INETSERVER);
            }
            printf("Disconnecting %s:%u\n", inet_ntoa(rip), INETSERVERPORT);
            NutTcpCloseSocket(sock);
        }

        NutSleep(5000);

        /*
         * Now let's use native calls.
         */
        if ((sock = NutTcpCreateSocket()) != 0) {

            /*
             * Connect a HTTP server in the Internet.
             */
            printf("Connecting %s:%u\r\n", inet_ntoa(rip), INETSERVERPORT);
            if (NutTcpConnect(sock, rip, INETSERVERPORT) == 0) {

                /*
                 * Send HTTP request to the server. NutTcpSend() doesn't
                 * guarantee to send out all bytes, thus the loop.
                 */
                strcpy(buff, "GET " INETURL " HTTP/1.0\r\nUser-Agent: Ethernut [en] (NutOS)\r\n\r\n");
                len = (int) strlen(buff);
                for (rc = 0; rc < len; rc += bite)
                    if ((bite = NutTcpSend(sock, buff + rc, len - rc)) <= 0)
                        break;

                /*
                 * Init measure values.
                 */
                start_time = NutGetTickCount();
                total_bytes = 0;

                /*
                 * Read server response and send it to the UART.
                 */
                while ((bite = NutTcpReceive(sock, buff, sizeof(buff) - 1)) > 0) {
                    total_bytes += bite;
                    buff[bite] = 0;
                    puts(buff);
                }
                printf("Transfered %lu bytes in %lu seconds\n", total_bytes, (NutGetTickCount() - start_time) / 16UL);
            } else {
                printf("Bad news, %s refuses the connection.\n", INETSERVER);
            }
            printf("Disconnecting %s:%u\n", inet_ntoa(rip), INETSERVERPORT);
            NutTcpCloseSocket(sock);
        }
    } else
        printf("Great news, %s has been removed!\n", INETSERVER);

    for (;;)
        NutSleep(1000);
}

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