From 3477e1a4f531ab4e3f9585ddd17bd99d985c94f6 Mon Sep 17 00:00:00 2001
From: ThorstenB <brehmt@gmail.com>
Date: Sat, 29 Oct 2011 21:15:29 +0200
Subject: [PATCH] terrasync improvements Detach from console to make "Ctrl-C"
 work for fgfs on Linux. Immediately start synchronization of current position
 when starting at run-time.

---
 simgear/scene/tsync/terrasync.cxx | 91 +++++++++++++++++++------------
 1 file changed, 57 insertions(+), 34 deletions(-)

diff --git a/simgear/scene/tsync/terrasync.cxx b/simgear/scene/tsync/terrasync.cxx
index ec2e5ca0..d48b39e9 100644
--- a/simgear/scene/tsync/terrasync.cxx
+++ b/simgear/scene/tsync/terrasync.cxx
@@ -486,7 +486,18 @@ bool SGTerraSync::SvnThread::syncTreeExternal(const char* dir)
     command = buf.str();
 #endif
     SG_LOG(SG_TERRAIN,SG_DEBUG, "sync command '" << command << "'");
+
+#ifdef SG_WINDOWS
+    // tbd: does Windows support "popen"?
     int rc = system( command.c_str() );
+#else
+    FILE* pipe = popen( command.c_str(), "r");
+    int rc=-1;
+    // wait for external process to finish
+    if (pipe)
+        rc = pclose(pipe);
+#endif
+
     if (rc)
     {
         SG_LOG(SG_TERRAIN,SG_ALERT,
@@ -701,12 +712,21 @@ void SGTerraSync::reinit()
         _svnThread->setExtSvnUtility(_terraRoot->getStringValue("ext-svn-utility","svn"));
 
         if (_svnThread->start())
+        {
             syncAirportsModels();
+            if (last_lat != NOWHERE && last_lon != NOWHERE)
+            {
+                // reschedule most recent position
+                int lat = last_lat;
+                int lon = last_lon;
+                last_lat = NOWHERE;
+                last_lon = NOWHERE;
+                schedulePosition(lat, lon);
+            }
+        }
     }
 
     _stalled_node->setBoolValue(_svnThread->_stalled);
-    last_lat = NOWHERE;
-    last_lon = NOWHERE;
 }
 
 void SGTerraSync::bind()
@@ -897,46 +917,49 @@ void SGTerraSync::syncAreas( int lat, int lon, int lat_dir, int lon_dir )
 
 bool SGTerraSync::schedulePosition(int lat, int lon)
 {
+    bool Ok = false;
+
     // Ignore messages where the location does not change
     if ( lat != last_lat || lon != last_lon )
     {
-        SG_LOG(SG_TERRAIN,SG_DEBUG, "Requesting scenery update for position " << 
-                                    lat << "," << lon);
-        int lat_dir, lon_dir, dist;
-        if ( last_lat == NOWHERE || last_lon == NOWHERE )
+        if (_svnThread->_running)
         {
-            lat_dir = lon_dir = 0;
-        } else
-        {
-            dist = lat - last_lat;
-            if ( dist != 0 )
+            SG_LOG(SG_TERRAIN,SG_DEBUG, "Requesting scenery update for position " <<
+                                        lat << "," << lon);
+            int lat_dir=0;
+            int lon_dir=0;
+            if ( last_lat != NOWHERE && last_lon != NOWHERE )
             {
-                lat_dir = dist / abs(dist);
-            }
-            else
-            {
-                lat_dir = 0;
-            }
-            dist = lon - last_lon;
-            if ( dist != 0 )
-            {
-                lon_dir = dist / abs(dist);
-            } else
-            {
-                lon_dir = 0;
+                int dist = lat - last_lat;
+                if ( dist != 0 )
+                {
+                    lat_dir = dist / abs(dist);
+                }
+                else
+                {
+                    lat_dir = 0;
+                }
+                dist = lon - last_lon;
+                if ( dist != 0 )
+                {
+                    lon_dir = dist / abs(dist);
+                } else
+                {
+                    lon_dir = 0;
+                }
             }
+
+            SG_LOG(SG_TERRAIN,SG_DEBUG, "Scenery update for " <<
+                   "lat = " << lat << ", lon = " << lon <<
+                   ", lat_dir = " << lat_dir << ",  " <<
+                   "lon_dir = " << lon_dir);
+
+            syncAreas( lat, lon, lat_dir, lon_dir );
+            Ok = true;
         }
-
-        SG_LOG(SG_TERRAIN,SG_DEBUG, "Scenery update for " << 
-               "lat = " << lat << ", lon = " << lon <<
-               ", lat_dir = " << lat_dir << ",  " <<
-               "lon_dir = " << lon_dir);
-
-        syncAreas( lat, lon, lat_dir, lon_dir );
-
         last_lat = lat;
         last_lon = lon;
-        return true;
     }
-    return false;
+
+    return Ok;
 }