مادة المقالة مأخوذة من قناة zen الخاصة بي .

الاتصال الداخلي على الوجهين

في المقالة الأخيرة ، تم الإعلان عن اتصال داخلي مزدوج ، وسوف نقوم بذلك.
. , . . 8000 . , — 16 ( , ). 160 . 320 . , "" . , — , "" .
, 16- µ- ( G.711) . . , , . , Wireshark RTP- µ- -.
, rtpsend, RTP-, UDP-.
, RTP-, , rtprecv, , , . , .
, , , 16-. . , .
. , . , , . . IP- , .
, :
struct _app_vars
{
  int  local_port;              
  int  remote_port;             
  char remote_addr[128];        
  MSDtmfGenCustomTone dtmf_cfg; 
};
typedef struct _app_vars app_vars;
vars.
:
void  scan_args(int argc, char *argv[], app_vars *v)
{
    char i;
    for (i=0; i<argc; i++)
    {
        if (!strcmp(argv[i], "--help"))
        {
            char *p=argv[0]; p=p + 2;
            printf("  %s walkie talkie\n\n", p);
            printf("--help      List of options.\n");
            printf("--version   Version of application.\n");
            printf("--addr      Remote abonent IP address string.\n");
            printf("--port      Remote abonent port number.\n");
            printf("--lport     Local port number.\n");
            printf("--gen       Generator frequency.\n");
            exit(0);
        }
        if (!strcmp(argv[i], "--version"))
        {
            printf("0.1\n");
            exit(0);
        }
        if (!strcmp(argv[i], "--addr"))
        {
            strncpy(v->remote_addr, argv[i+1], 16);
            v->remote_addr[16]=0;
            printf("remote addr: %s\n", v->remote_addr);
        }
        if (!strcmp(argv[i], "--port"))
        {
            v->remote_port=atoi(argv[i+1]);
            printf("remote port: %i\n", v->remote_port);
        }
        if (!strcmp(argv[i], "--lport"))
        {
            v->local_port=atoi(argv[i+1]);
            printf("local port : %i\n", v->local_port);
        }
        if (!strcmp(argv[i], "--gen"))
        {
            v -> dtmf_cfg.frequencies[0] = atoi(argv[i+1]);
                printf("gen freq : %i\n", v -> dtmf_cfg.frequencies[0]);
        }
    }
}
, vars. , , , — .
- , - 16 . , 32- .
:
#include <mediastreamer2/mssndcard.h>
#include <mediastreamer2/dtmfgen.h>
#include <mediastreamer2/msrtp.h>
#include "mstest_common.c"
struct _app_vars
{
    int  local_port;              
    int  remote_port;             
    char remote_addr[128];        
    MSDtmfGenCustomTone dtmf_cfg; 
};
typedef struct _app_vars app_vars;
RtpSession* create_duplex_rtp_session(app_vars v)
{
    RtpSession *session = create_rtpsession (v.local_port, v.local_port + 1, FALSE, RTP_SESSION_SENDRECV);
    rtp_session_set_remote_addr_and_port(session, v.remote_addr, v.remote_port, v.remote_port + 1);
    rtp_session_set_send_payload_type(session, PCMU);
    return session;
}
void  scan_args(int argc, char *argv[], app_vars *v)
{
    char i;
    for (i=0; i<argc; i++)
    {
        if (!strcmp(argv[i], "--help"))
        {
            char *p=argv[0]; p=p + 2;
            printf("  %s walkie talkie\n\n", p);
            printf("--help      List of options.\n");
            printf("--version   Version of application.\n");
            printf("--addr      Remote abonent IP address string.\n");
            printf("--port      Remote abonent port number.\n");
            printf("--lport     Local port number.\n");
            printf("--gen       Generator frequency.\n");
            exit(0);
        }
        if (!strcmp(argv[i], "--version"))
        {
            printf("0.1\n");
            exit(0);
        }
        if (!strcmp(argv[i], "--addr"))
        {
            strncpy(v->remote_addr, argv[i+1], 16);
            v->remote_addr[16]=0;
            printf("remote addr: %s\n", v->remote_addr);
        }
        if (!strcmp(argv[i], "--port"))
        {
            v->remote_port=atoi(argv[i+1]);
            printf("remote port: %i\n", v->remote_port);
        }
        if (!strcmp(argv[i], "--lport"))
        {
            v->local_port=atoi(argv[i+1]);
            printf("local port : %i\n", v->local_port);
        }
        if (!strcmp(argv[i], "--gen"))
        {
            v -> dtmf_cfg.frequencies[0] = atoi(argv[i+1]);
                printf("gen freq : %i\n", v -> dtmf_cfg.frequencies[0]);
        }
    }
}
int main(int argc, char *argv[])
{
    
    app_vars vars={5004, 7010, "127.0.0.1", {0}};
    
    scan_args(argc, argv, &vars);
    ms_init();
    
    MSSndCard *snd_card =
        ms_snd_card_manager_get_default_card(ms_snd_card_manager_get());
    MSFilter *snd_card_read = ms_snd_card_create_reader(snd_card);
    MSFilter *dtmfgen = ms_filter_new(MS_DTMF_GEN_ID);
    MSFilter *rtpsend = ms_filter_new(MS_RTP_SEND_ID);
    
    MSFilter *encoder = ms_filter_create_encoder("PCMU");
    
    register_payloads();
    
    RtpSession* rtp_session= create_duplex_rtp_session(vars);
    ms_filter_call_method(rtpsend, MS_RTP_SEND_SET_SESSION, rtp_session);
    
    ms_filter_link(snd_card_read, 0, dtmfgen, 0);
    ms_filter_link(dtmfgen, 0, encoder, 0);
    ms_filter_link(encoder, 0, rtpsend, 0);
    
    MSFilter *rtprecv = ms_filter_new(MS_RTP_RECV_ID);
    ms_filter_call_method(rtprecv, MS_RTP_RECV_SET_SESSION, rtp_session);
    
    MSFilter *decoder=ms_filter_create_decoder("PCMU");
    
    MSFilter *snd_card_write = ms_snd_card_create_writer(snd_card);
    
    ms_filter_link(rtprecv, 0, decoder, 0);
    ms_filter_link(decoder, 0,  snd_card_write, 0);
    
    MSTicker *ticker = ms_ticker_new();
    
    ms_ticker_attach(ticker, snd_card_read);
    ms_ticker_attach(ticker, rtprecv);
       
    if (vars.dtmf_cfg.frequencies[0])
    {
        
        vars.dtmf_cfg.duration = 10000;
        vars.dtmf_cfg.amplitude = 1.0;
    }
    
    while(TRUE)
    {
        if(vars.dtmf_cfg.frequencies[0])
        {
            
            ms_filter_call_method(dtmfgen, MS_DTMF_GEN_PLAY_CUSTOM,
                    (void*)&vars.dtmf_cfg);
        }
        
        ms_usleep(20000);
    }
}
. . , . TShark :
$ sudo tshark -i lo -f "udp dst port 7010" -P -V -O RTP -o rtp.heuristic_rtp:TRUE -x
, - . , "" :
$ ./mstest8 --port 9010 --lport 7010
, IP- 127.0.0.1 ( ).
, . , :
$ ./mstest8  --port 7010 --lport 9010 --gen 440
, TShark "" , .
, , "--gen 440". . , . , .
IP-, — .
— , , - .