A patch against VideoLAN's miniSAPServer to allow custom SDP announcements

minisapserver-0.3.6-customsdp.diff

diff -ruN minisapserver-0.3.6/message.cpp minisapserver-0.3.6-customsdp/message.cpp
--- minisapserver-0.3.6/message.cpp	2009-01-11 19:53:25.000000000 +0000
+++ minisapserver-0.3.6-customsdp/message.cpp	2009-04-15 00:21:19.000000000 +0100
@@ -96,59 +96,65 @@
 
 bool Message::AddProgram(Program *p)
 {
+    string sdp = "v=0\r\n";  // SDP version
     /* FIXME */
     /* RFC 2327 Compliance ? */
-    string ipv = (p->GetAddress().find(':') == string::npos) ? "IP4" : "IP6";
-
-    string sdp = "v=0\r\n";  // SDP version
-    string ver="";
-    stringstream ssin(ver);
-    ssin << version;
-    ver = ssin.str();
-    sdp += "o=" + p->GetUser() + " " + ver + " 1 IN " + ipv + " "
-              + p->GetMachine() + "\r\n";
-    sdp += "s=" + p->GetName() + "\r\n";
-    sdp += "u=" + p->GetSite() + "\r\n";
-
-    sdp += "c=IN " + ipv + " " + p->GetAddress();
-    if (ipv == "IP4")
-        sdp += "/" + p->GetTTL(); /* only IPv4 multicast shall have a TTL */
-    sdp += "\r\n";
-
-    if (p->IsPermanent())
-        sdp += "t=0 0\r\n";
+    if (p->HasCustomSDP())
+    {
+        sdp = p->GetCustomSDP();
+    }
     else
-        return false;
-
-    /* Session level attributes */
-    sdp += "a=tool:" + (string)PACKAGE_STRING + "\r\n";
-
-    if (p->HasPlGroup())
-        sdp += "a=x-plgroup:" + p->GetPlGroup() + "\r\n";
+    {
+        string ipv = (p->GetAddress().find(':') == string::npos) ? "IP4" : "IP6";
 
-    /* Media and media-level attributes */
-    sdp += "a=type:broadcast\r\n";
-    sdp += "a=charset:UTF-8\r\n";
-
-    char portbuf[6];
-    snprintf(portbuf, sizeof(portbuf), "%u", (unsigned)p->GetPort());
-    string port = portbuf;
-    string m = "m=video " + port + " "
-             + (p->IsRTP() ? "RTP/AVP 33" : "udp mpeg") +"\r\n";
+        string ver="";
+        stringstream ssin(ver);
+        ssin << version;
+        ver = ssin.str();
+        sdp += "o=" + p->GetUser() + " " + ver + " 1 IN " + ipv + " "
+                  + p->GetMachine() + "\r\n";
+        sdp += "s=" + p->GetName() + "\r\n";
+        sdp += "u=" + p->GetSite() + "\r\n";
+
+        sdp += "c=IN " + ipv + " " + p->GetAddress();
+        if (ipv == "IP4")
+            sdp += "/" + p->GetTTL(); /* only IPv4 multicast shall have a TTL */
+        sdp += "\r\n";
+
+        if (p->IsPermanent())
+            sdp += "t=0 0\r\n";
+        else
+            return false;
+
+        /* Session level attributes */
+        sdp += "a=tool:" + (string)PACKAGE_STRING + "\r\n";
+
+        if (p->HasPlGroup())
+            sdp += "a=x-plgroup:" + p->GetPlGroup() + "\r\n";
+
+        /* Media and media-level attributes */
+        sdp += "a=type:broadcast\r\n";
+        sdp += "a=charset:UTF-8\r\n";
+
+        char portbuf[6];
+        snprintf(portbuf, sizeof(portbuf), "%u", (unsigned)p->GetPort());
+        string port = portbuf;
+        string m = "m=video " + port + " "
+                 + (p->IsRTP() ? "RTP/AVP 33" : "udp mpeg") +"\r\n";
 
-    if (p->IsRTP())
-    {
-        m += "a=rtpmap:33 MP2T/90000\r\n";
-        if (p->IsRTP() & 1)
+        if (p->IsRTP())
         {
-           snprintf(portbuf, sizeof(portbuf), "%u", 1 + p->GetPort());
-           port = portbuf;
-           m += "a=rtcp:" + port + "\r\n";
+            m += "a=rtpmap:33 MP2T/90000\r\n";
+            if (p->IsRTP() & 1)
+            {
+               snprintf(portbuf, sizeof(portbuf), "%u", 1 + p->GetPort());
+               port = portbuf;
+               m += "a=rtcp:" + port + "\r\n";
+            }
         }
-    }
-
-    sdp += m;
 
+        sdp += m;
+    }
     puts (sdp.c_str ());
 
     if (msg_len + sdp.length () > 1024)
diff -ruN minisapserver-0.3.6/parser.cpp minisapserver-0.3.6-customsdp/parser.cpp
--- minisapserver-0.3.6/parser.cpp	2009-01-11 19:50:43.000000000 +0000
+++ minisapserver-0.3.6-customsdp/parser.cpp	2009-04-14 23:38:48.000000000 +0100
@@ -373,6 +373,12 @@
             something=1;
             pp->SetPort(atoi(tline));
         }
+        if(strstr(line,"customsdp="))
+        {
+            strgeta(line,tline,'=');
+            something=1;
+            pp->SetCustomSDP(tline);
+        }
     }
 
     if(something)
diff -ruN minisapserver-0.3.6/program.cpp minisapserver-0.3.6-customsdp/program.cpp
--- minisapserver-0.3.6/program.cpp	2009-01-11 19:50:43.000000000 +0000
+++ minisapserver-0.3.6-customsdp/program.cpp	2009-04-15 00:02:39.000000000 +0100
@@ -27,6 +27,7 @@
 #include <arpa/inet.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <errno.h>
 #include <string>
 #include <vector>
 using namespace std;
@@ -43,6 +44,7 @@
     machine = "localhost";
     user = "VideoLAN";
     site = "http://www.videolan.org";
+	custom_sdp = "";
 }
 Program::~Program() {return;}
 
@@ -54,11 +56,11 @@
 uint16_t Program::GetPort(void){return port;}
 string Program::GetTTL(void){return program_ttl;}
 string Program::GetPlGroup(void){return pl_group;}
-
+string Program::GetCustomSDP(void){return custom_sdp;}
 bool   Program::IsPermanent(void){return permanent;}
 bool   Program::IsRTP(void){return b_rtp;}
 bool   Program::HasPlGroup(void){return b_has_pl_group;}
-
+bool   Program::HasCustomSDP(void){return custom_sdp.size() ? true : false;}
 void Program::SetName(const char* n){name=n;}
 void Program::SetUser(const char* u){user=u;}
 void Program::SetMachine(const char* m){machine=m;}
@@ -68,7 +70,6 @@
 void Program::SetRTP(bool b){b_rtp = b;}
 void Program::SetHasPlGroup(bool b){b_has_pl_group = b ;}
 void Program::SetPort(uint16_t p) { port = p; }
-
 void Program::SetTTL(const char *p){program_ttl=p;}
 
 Program::Program(string n, string u, string m, string s, string a,uint16_t p)
@@ -82,3 +83,25 @@
     port=p;
     permanent=true;
 }
+
+void Program::SetCustomSDP(const char *fname)
+{
+    /* Although it's a (relatively small) fixed-sized buffer, we can't serve 
+     * SDP any larger than this in any case - see the condition in
+     * Message::AddProgram(): 
+     *   if(msg_len + sdp.length () > 1024) - RFC 2974 Chap 6.
+     */
+    char buf[1024]; 
+    FILE *f;
+    ssize_t l;
+    
+    if(NULL == (f = fopen(fname, "rb")))
+    {
+        fprintf(stderr, "%s: %s\n", fname, strerror(errno));
+        exit(1);
+    }
+    l = fread(buf, 1, sizeof(buf) - 1, f);
+    fclose(f);
+    buf[l] = '\0';
+    custom_sdp = buf;
+}
diff -ruN minisapserver-0.3.6/program.h minisapserver-0.3.6-customsdp/program.h
--- minisapserver-0.3.6/program.h	2009-01-11 19:50:43.000000000 +0000
+++ minisapserver-0.3.6-customsdp/program.h	2009-04-15 00:20:16.000000000 +0100
@@ -38,6 +38,7 @@
     uint16_t GetPort();
     string GetTTL();
     string GetPlGroup();
+    string GetCustomSDP();
 
     /* Functions to set the values */
     void SetName(const char*);
@@ -50,10 +51,12 @@
     void SetPlGroup(const char *);
     void SetHasPlGroup(bool);
     void SetRTP(bool);
+    void SetCustomSDP(const char *);
 
     bool IsPermanent();
     bool IsRTP();
     bool HasPlGroup();
+    bool HasCustomSDP();
 
   private:
     string name;
@@ -63,6 +66,7 @@
     string address;
     string program_ttl;
     string pl_group;
+    string custom_sdp;
     bool permanent;
     bool b_rtp;
     bool b_has_pl_group;
diff -ruN minisapserver-0.3.6/sap.cfg minisapserver-0.3.6-customsdp/sap.cfg
--- minisapserver-0.3.6/sap.cfg	2008-02-06 21:05:34.000000000 +0000
+++ minisapserver-0.3.6-customsdp/sap.cfg	2009-04-15 00:18:40.000000000 +0100
@@ -39,7 +39,9 @@
 # The name of the playlistgroup your announce will be part of in the VLC playlist
 playlist_group=organisationTV 
 
-
+# If you wish to send custom SDP to clients, specify the full path to the
+# SDP file
+#customsdp=/path/to/broadcast.sdp
 
 # IPv6 example
 [program]