libsrt-sys 1.4.13

Bindings for libsrt
/*
 * SRT - Secure, Reliable, Transport
 * Copyright (c) 2017 Haivision Systems Inc.
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; If not, see <http://www.gnu.org/licenses/>
 */

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


#include "srt.h"

int main(int argc, char** argv)
{
    int globstatus = 0;

    int ss, st;
    struct sockaddr_in sa;
    int yes = 1;
    struct sockaddr_storage their_addr;
    SRT_SOCKGROUPDATA* grpdata = NULL;

    if (argc != 3) {
      fprintf(stderr, "Usage: %s <host> <port>\n", argv[0]);
      return 1;
    }

    printf("srt startup\n");
    srt_startup();
    // Since now, srt_cleanup() must be done before exiting.

    printf("srt socket\n");
    ss = srt_create_socket();
    if (ss == SRT_ERROR)
    {
        fprintf(stderr, "srt_socket: %s\n", srt_getlasterror_str());
        globstatus = 1;
        goto cleanup;
    }
    // Now that the socket is created, jump to 'end' on error.

    printf("srt bind address\n");
    if (0 == strcmp(argv[1], "0"))
    {
        memset(&sa, 0, sizeof sa);
    }
    else if (inet_pton(AF_INET, argv[1], &sa.sin_addr) != 1)
    {
        fprintf(stderr, "srt_bind: Can't resolve address: %s\n", argv[1]);
        globstatus = 1;
        goto end;
    }
    sa.sin_family = AF_INET;
    sa.sin_port = htons(atoi(argv[2]));

    printf("srt setsockflag: groupconnect\n");
    srt_setsockflag(ss, SRTO_GROUPCONNECT, &yes, sizeof yes);

    printf("srt bind\n");
    st = srt_bind(ss, (struct sockaddr*)&sa, sizeof sa);
    if (st == SRT_ERROR)
    {
        fprintf(stderr, "srt_bind: %s\n", srt_getlasterror_str());
        globstatus = 1;
        goto end;
    }

    printf("srt listen\n");

    // We set here 10, just for a case. Every unit in this number
    // defines a maximum number of connections that can be pending
    // simultaneously - it doesn't matter here if particular connection
    // will belong to a bonding group or will be a single-socket connection.
    st = srt_listen(ss, 10);
    if (st == SRT_ERROR)
    {
        fprintf(stderr, "srt_listen: %s\n", srt_getlasterror_str());
        globstatus = 1;
        goto end;
    }

    // In this example, there will be prepared an array of 10 items.
    // The listener, however, doesn't know how many member connections
    // one bonded connection will contain, so a real application should be
    // prepared for dynamically adjusting the array size.
    const size_t N = 10;
    grpdata = calloc(N, sizeof (SRT_SOCKGROUPDATA));

    printf("srt accept\n");
    int addr_size = sizeof their_addr;
    SRTSOCKET their_fd = srt_accept(ss, (struct sockaddr *)&their_addr, &addr_size);

    // You never know if `srt_accept` is going to give you a socket or a group.
    // You have to check it on your own. The SRTO_GROUPCONNECT flag doesn't disallow
    // single socket connections.
    int isgroup = their_fd & SRTGROUP_MASK;

    // Still, use the same procedure for receiving, no matter if
    // this is a bonded or single connection.
    int i;
    for (i = 0; i < 100; i++)
    {
        printf("srt recvmsg #%d... ",i);
        char msg[2048];
        SRT_MSGCTRL mc = srt_msgctrl_default;
        mc.grpdata = grpdata;
        mc.grpdata_size = N;
        st = srt_recvmsg2(their_fd, msg, sizeof msg, &mc);
        if (st == SRT_ERROR)
        {
            fprintf(stderr, "srt_recvmsg: %s\n", srt_getlasterror_str());
            goto end;
        }

        printf("Got msg of len %d << %s (%s)\n", st, msg, isgroup ? "group" : "single");

        if (!isgroup)
            continue;

        if (!mc.grpdata)
            printf("Group status: [%zi] members > %zi, can't handle.\n", mc.grpdata_size, N);
        else
        {
            printf(" ++ Group status [%zi]: ", mc.grpdata_size);
            size_t z;
            for (z = 0; z < mc.grpdata_size; ++z)
            {
                printf( "[%zd] result=%d state=%s ", z, mc.grpdata[z].result,
                        mc.grpdata[z].sockstate <= SRTS_CONNECTING ? "pending" :
                        mc.grpdata[z].sockstate == SRTS_CONNECTED ? "connected" : "broken");
            }
            printf("\n");
        }
    }

end:
    free(grpdata);
    printf("srt close\n");
    st = srt_close(ss);
    if (st == SRT_ERROR)
    {
        fprintf(stderr, "srt_close: %s\n", srt_getlasterror_str());
        // But not matter, we're finishing here.
    }

cleanup:
    printf("srt cleanup\n");
    srt_cleanup();
    return globstatus;
}