From 4a82d793a332fd4e38da6eed77e3a4c6918276f6 Mon Sep 17 00:00:00 2001
From: Raphael Coeffic <rco@iptel.org>
Date: Tue, 27 Feb 2007 13:27:32 +0000
Subject: [PATCH] - added a centralized pseudo-random number function. -
 changed rand() calls to get_random(). - added/fixed ssrc (RTP header)
 generation.

git-svn-id: http://svn.berlios.de/svnroot/repos/sems/trunk@252 8eb893ce-cfd4-0310-b710-fb5ebe64c474
---
 core/AmRtpStream.cpp        |  3 ++-
 core/AmRtpStream.h          |  2 +-
 core/AmSession.cpp          |  7 +------
 core/AmSessionContainer.cpp |  9 ---------
 core/AmUtils.cpp            | 27 +++++++++++++++++++++++++++
 core/AmUtils.h              |  5 +++++
 core/sems.cpp               |  2 ++
 7 files changed, 38 insertions(+), 17 deletions(-)

diff --git a/core/AmRtpStream.cpp b/core/AmRtpStream.cpp
index 67c859a5..bdb0582b 100644
--- a/core/AmRtpStream.cpp
+++ b/core/AmRtpStream.cpp
@@ -176,7 +176,7 @@ int AmRtpStream::send( unsigned int ts, unsigned char* buffer, unsigned int size
     rp.marker = false;
     rp.sequence = sequence++;
     rp.timestamp = ts;   
-    rp.ssrc = 0; //l_ssrc;
+    rp.ssrc = l_ssrc;
     rp.compile((unsigned char*)buffer,size);
 
     rp.setAddr(&r_saddr);
@@ -386,6 +386,7 @@ AmRtpStream::AmRtpStream(AmSession* _s)
     l_saddr.sin_addr.s_addr = INADDR_ANY;
 #endif
 
+    l_ssrc = get_random();
 }
 
 AmRtpStream::~AmRtpStream()
diff --git a/core/AmRtpStream.h b/core/AmRtpStream.h
index 367a75b2..de2f1d9a 100644
--- a/core/AmRtpStream.h
+++ b/core/AmRtpStream.h
@@ -123,7 +123,7 @@ protected:
     /** the recv_offset initialized ?  */ 
     bool           recv_offset_i;
 
-	//    unsigned int   l_ssrc;
+    unsigned int   l_ssrc;
     unsigned int   r_ssrc;
     bool           r_ssrc_i;
 
diff --git a/core/AmSession.cpp b/core/AmSession.cpp
index ea5c4b6c..31dafe97 100644
--- a/core/AmSession.cpp
+++ b/core/AmSession.cpp
@@ -349,17 +349,12 @@ void AmSession::destroy()
 
 string AmSession::getNewId()
 {
-    static AmMutex _m;
-    
     struct timeval t;
     gettimeofday(&t,NULL);
 
     string id = "";
 
-    _m.lock();
-    id += int2hex(rand()) + "-";
-    _m.unlock();
-
+    id += int2hex(get_random()) + "-";
     id += int2hex(t.tv_sec) + int2hex(t.tv_usec) + "-";
     id += int2hex((unsigned int) pthread_self());
 
diff --git a/core/AmSessionContainer.cpp b/core/AmSessionContainer.cpp
index e3233a98..4246e158 100644
--- a/core/AmSessionContainer.cpp
+++ b/core/AmSessionContainer.cpp
@@ -59,15 +59,6 @@ void AmSessionContainer::on_stop()
 
 void AmSessionContainer::run()
 {
-    int seed=0;
-    FILE* fp_rand = fopen("/dev/random","r");
-    if(fp_rand){
-	fread(&seed,sizeof(int),1,fp_rand);
-	fclose(fp_rand);
-    }
-    seed += getpid();
-    seed += time(0);
-    srand(seed);
 
     while(1){
 
diff --git a/core/AmUtils.cpp b/core/AmUtils.cpp
index ae1aef24..cb279e0b 100644
--- a/core/AmUtils.cpp
+++ b/core/AmUtils.cpp
@@ -701,3 +701,30 @@ string get_header_param(const string& hdr_string,
   }
   return "";
 }
+
+
+// support for thread-safe pseudo-random numbers
+static unsigned int _s_rand=0;
+static AmMutex _s_rand_mut;
+
+void init_random()
+{
+    int seed=0;
+    FILE* fp_rand = fopen("/dev/random","r");
+    if(fp_rand){
+	fread(&seed,sizeof(int),1,fp_rand);
+	fclose(fp_rand);
+    }
+    seed += getpid();
+    seed += time(0);
+    _s_rand = seed;
+}
+
+unsigned int get_random()
+{
+    _s_rand_mut.lock();
+    unsigned int r = rand_r(&_s_rand);
+    _s_rand_mut.unlock();
+    
+    return r;
+}
diff --git a/core/AmUtils.h b/core/AmUtils.h
index a61a64b2..2bc21e1a 100644
--- a/core/AmUtils.h
+++ b/core/AmUtils.h
@@ -250,6 +250,11 @@ string strip_header_params(const string& hdr_string);
   // get a header parameter value
 string get_header_param(const string& hdr_string, const string& param_name);
 
+// support for thread-safe pseudo-random numbers
+void init_random();
+unsigned int get_random();
+
+
 #endif
 
 // Local Variables:
diff --git a/core/sems.cpp b/core/sems.cpp
index 63828708..f87361d4 100644
--- a/core/sems.cpp
+++ b/core/sems.cpp
@@ -371,6 +371,8 @@ int main(int argc, char* argv[])
     if(AmPlugIn::instance()->load(AmConfig::PlugInPath, AmConfig::LoadPlugins))
 	return -1;
 
+    init_random();
+
     DBG("Starting session container\n");
     AmSessionContainer::instance()->start();