SDP-Parser and codec problem

These are my SDP outputs:

LOCAL:
v=0
o=3686278856 0 0 IN IP4 10.0.0.27
s=Session SIP/SDP
c=IN IP4 10.0.0.27
t=0 0
a=rtpmap:8 PCMA/8000/1
a=rtpmap:18 G729/8000/1
a=fmtp:18 annexb=no
a=rtpmap:0 PCMU/8000/1
a=rtpmap:111 ILBC/8000/1
a=fmtp:111 mode=30
a=ptime:20
m=audio 3001 RTP/AVP 8 18 0 111
a=rtpmap:8 PCMA/8000/1
a=rtpmap:18 G729/8000/1
a=fmtp:18 annexb=no
a=rtpmap:0 PCMU/8000/1
a=rtpmap:111 ILBC/8000/1
a=fmtp:111 mode=30
a=ptime:20

REMOTE: SIP SERVER:

v=0
o=- 150969000 1806128112579501 IN IP4 [IP_OF_MY_SIP_SERVER]
s=Dialogic_SIP_CCLIB
c=IN IP4 217.65.176.110
t=0 0
a=rtpmap:8 PCMA/8000/1
a=ptime:20
a=sendrecv
m=audio 21104 RTP/AVP 8
c=IN IP4 217.65.176.110
a=rtpmap:8 PCMA/8000/1
a=ptime:20
a=sendrecv

new SDP:

v=0
o=- 150969000 1806128112579501 IN IP4 [IP_OF_MY_SIP_SERVER]
s=Dialogic_SIP_CCLIB
c=IN IP4 10.0.0.27
t=0 0
m=audio 3001 RTP/AVP 8
a=rtpmap:8 PCMA/8000/1
--------------------------------------------

1.FIRST PROBLEM (As far as I see solved)
1.1.Problem Definition

I try to parse SDP string below with the newest version of 
org.zoolu.sdp.SDPParser (with Generic Vector).
----
v=0
o=- 151044168 1474421261158700 IN IP4 217.65.174.109
s=Dialogic_SIP_CCLIB
t=0 0
m=audio 22824 RTP/AVP 8
c=IN IP4 217.65.176.110
a=rtpmap:8 PCMA/8000/1
a=ptime:20
a=sendrecv
-----
But, in this method, it cant parse "m" field. because, it begins before "c"
in my  SDP.

public SessionDescriptor(String sdp) {
        SdpParser par = new SdpParser(sdp);
        // parse mandatory fields
        v = par.parseSdpField('v');
        if (v == null)
            v = new SdpField('v', "0");
        o = par.parseOriginField();
        if (o == null)
            o = new OriginField("unknown");
        s = par.parseSessionNameField();
        if (s == null)
            s = new SessionNameField();
        c = par.parseConnectionField();
        if (c == null)
            c = new ConnectionField("IP4", "0.0.0.0");
        t = par.parseTimeField();
        if (t == null)
            t = new TimeField();
        while (par.hasMore()
                && (!par.startsWith("a=") && !par.startsWith("m="))) { // skip
            // unknown
            // lines..
            par.goToNextLine();
        }
        // parse session attributes
        av = new Vector<AttributeField>();
        while (par.hasMore() && par.startsWith("a=")) {
            AttributeField attribute = par.parseAttributeField();
            av.addElement(attribute);
        }
        // parse media descriptors
        media = new Vector<MediaDescriptor>();
        MediaDescriptor md;
        while ((md = par.parseMediaDescriptor()) != null) {
            addMediaDescriptor(md);
        }
    }

1.2 MY CURRENT SOLUTION FOR THE FIRST PROBLEM
The order of SIP's fields can be change, so I need to use a switch to
handle it.
And also, when switch comes to 'm', I have needed to change
SdpParser.java's line 214    , and cancel this line "index = end;"...

 Altered version of the method:
public SessionDescriptor(String sdp) {
        SdpParser par = new SdpParser(sdp);
        // parse mandatory fields

       while(par.charAt(0)!='a'){
        char  charSwitch=    par.getRemainingString().charAt(0);      
       switch(charSwitch){
       case 'v':{
           v = par.parseSdpField('v');
            if (v == null)
                v = new SdpField('v', "0");
               break;
       }
       case 'o':{
           o = par.parseOriginField();
            if (o == null)
                o = new OriginField("unknown");
             break;
       }
       case 's':{

            s = par.parseSessionNameField();
            if (s == null)
                s = new SessionNameField();
             break;
       }
       case 't':{
           t = par.parseTimeField();
            if (t == null)
                t = new TimeField();
            break;
       }
       case 'c':{
           c = par.parseConnectionField();
            if (c == null)
                c = new ConnectionField("IP4", "0.0.0.0");
            break;
       }
       case 'm':{
        // parse media descriptors
            media = new Vector<MediaDescriptor>();
            MediaDescriptor md;

            while ((md = par.parseMediaDescriptor()) != null) {
                addMediaDescriptor(md);
            }

       }

       }

       }

        while (par.hasMore()
                && (!par.startsWith("a=") && !par.startsWith("m="))) { // skip
            // unknown
            // lines..
            par.goToNextLine();
        }
        // parse session attributes
        av = new Vector<AttributeField>();
        while (par.hasMore() && par.startsWith("a=")) {
            AttributeField attribute = par.parseAttributeField();
            av.addElement(attribute);
        }

    }

2.SECOND PROBLEM
2.2 DEFINITION OF THE 2. PROBLEM             
"I can send my voice to mobile phone, but can not receive."
After solving the first problem ; I can parse the SDP right, and my
LOCAL-REMOT SDP outputs:
LOCAL:
v=0
o=3686278856 0 0 IN IP4 10.0.0.27
s=Session SIP/SDP
c=IN IP4 10.0.0.27
t=0 0
a=rtpmap:8 PCMA/8000/1
a=rtpmap:18 G729/8000/1
a=fmtp:18 annexb=no
a=rtpmap:0 PCMU/8000/1
a=rtpmap:111 ILBC/8000/1
a=fmtp:111 mode=30
a=ptime:20
m=audio 3001 RTP/AVP 8 18 0 111
a=rtpmap:8 PCMA/8000/1
a=rtpmap:18 G729/8000/1
a=fmtp:18 annexb=no
a=rtpmap:0 PCMU/8000/1
a=rtpmap:111 ILBC/8000/1
a=fmtp:111 mode=30
a=ptime:20

SIP SERVER:
v=0
o=- 150969000 1806128112579501 IN IP4 217.65.176.110
s=Dialogic_SIP_CCLIB
c=IN IP4 217.65.176.110
t=0 0
a=rtpmap:8 PCMA/8000/1
a=ptime:20
a=sendrecv
m=audio 21104 RTP/AVP 8
c=IN IP4 217.65.176.110
a=rtpmap:8 PCMA/8000/1
a=ptime:20
a=sendrecv

new SDP:

v=0
o=- 150969000 1806128112579501 IN IP4 217.65.176.110
s=Dialogic_SIP_CCLIB
c=IN IP4 10.0.0.27
t=0 0
m=audio 3001 RTP/AVP 8
a=rtpmap:8 PCMA/8000/1

Kind Regards,
Murat Döner
from TURAN
Original issue reported on code.google.com by kuru...@gmail.com on 13 Apr 2010 at 12:08
sksushilkumar / red5phone

SDP-Parser and codec problem #108
