From Stephan Huber,

"Attached you'll find a proposal for using different
protocols. The idea behind the new code is:

1.) plugins/apps register protocols which they can handle. This is done
via osgDB::Registry::registerProtocol(aProtocolName). Plugins register
supported protocols as usual via ReaderWriter::supportsProtocol(..), the
Registry is updated accordingly.

2.) osgDB::containsServerAddress checks first for an appearance of "://"
in the filename and then checks the protocol against the set of
registered protocols via Registry::isProtocolRegistered(aProtocollName)

3.) the other getServer*-functions changed as well, there's even a
getServerProtocol-function


With these changes filenames/Urls get routed to loaded plugins even with
different protocols than 'http'."

include/osgDB/FileNameUtils

@@ -40,6 +40,7 @@ extern OSGDB_EXPORT bool equalCaseInsensitive(const std::string& lhs,const std::
 extern OSGDB_EXPORT bool equalCaseInsensitive(const std::string& lhs,const char* rhs);
 
 extern OSGDB_EXPORT bool containsServerAddress(const std::string& filename);
+extern OSGDB_EXPORT std::string getServerProtocol(const std::string& filename);
 extern OSGDB_EXPORT std::string getServerAddress(const std::string& filename);
 extern OSGDB_EXPORT std::string getServerFileName(const std::string& filename);
 

include/osgDB/Registry

@@ -479,6 +479,12 @@ class OSGDB_EXPORT Registry : public osg::Referenced
         /** Add an Archive extension.*/
         void addArchiveExtension(const std::string ext);
         
+        /** registers a protocol */
+        void registerProtocol(const std::string& protocol);
+        
+        /** returns true, if named protocol is registered */
+        bool isProtocolRegistered(const std::string& protocol);
+        
     protected:
 
         virtual ~Registry();
@@ -492,6 +498,8 @@ class OSGDB_EXPORT Registry : public osg::Referenced
         typedef std::map<std::string, ObjectTimeStampPair >             ObjectCache;
         typedef std::map<std::string, osg::ref_ptr<osgDB::Archive> >    ArchiveCache;
         
+        typedef std::set<std::string>                                   RegisteredProtocolsSet;
+
         /** constructor is private, as its a singleton, preventing
             construction other than via the instance() method and
             therefore ensuring only one copy is ever constructed*/
@@ -509,6 +517,8 @@ class OSGDB_EXPORT Registry : public osg::Referenced
         
         bool                                        _createNodeFromImage;
         
+        RegisteredProtocolsSet                      _registeredProtocols;
+
         osg::Object*       readObject(DotOsgWrapperMap& dowMap,Input& fr);
 
         void eraseWrapper(DotOsgWrapperMap& wrappermap,DotOsgWrapper* wrapper);

src/osgDB/FileNameUtils.cpp

@@ -179,26 +179,42 @@ bool osgDB::equalCaseInsensitive(const std::string& lhs,const char* rhs)
     return true;
 }
 
+
+
 bool osgDB::containsServerAddress(const std::string& filename)
 {
-    // need to check for http://
+    // need to check for ://
-    if (filename.size()<7) return false;
+    std::string::size_type pos(filename.find_first_of("://"));
-    if (filename.compare(0,7,"http://")==0) return true;
+    if (pos == std::string::npos) 
         return false;
+    std::string proto(filename.substr(0, pos));
+    
+    return Registry::instance()->isProtocolRegistered(proto);
+}
+
+std::string osgDB::getServerProtocol(const std::string& filename)
+{
+    std::string::size_type pos(filename.find_first_of("://"));
+    if (pos != std::string::npos)
+        return filename.substr(0,pos);
+
+    return "";
 }
 
 std::string osgDB::getServerAddress(const std::string& filename)
 {
-    if (filename.size()>=7 && filename.compare(0,7,"http://")==0)
+    std::string::size_type pos(filename.find_first_of("://"));
+    
+    if (pos != std::string::npos)
     {
-        std::string::size_type pos_slash = filename.find_first_of('/',7);
+        std::string::size_type pos_slash = filename.find_first_of('/',pos+3);
         if (pos_slash!=std::string::npos)
         {
-            return filename.substr(7,pos_slash-7);
+            return filename.substr(pos+3,pos_slash-pos-3);
         }
         else
         {
-            return filename.substr(7,std::string::npos);
+            return filename.substr(pos+3,std::string::npos);
         }
     }
     return "";
@@ -206,9 +222,11 @@ std::string osgDB::getServerAddress(const std::string& filename)
 
 std::string osgDB::getServerFileName(const std::string& filename)
 {
-    if (filename.size()>=7 && filename.compare(0,7,"http://")==0)
+    std::string::size_type pos(filename.find_first_of("://"));
+
+    if (pos != std::string::npos)
     {
-        std::string::size_type pos_slash = filename.find_first_of('/',7);
+        std::string::size_type pos_slash = filename.find_first_of('/',pos+3);
         if (pos_slash!=std::string::npos)
         {
             return filename.substr(pos_slash+1,std::string::npos);

src/osgDB/ReaderWriter.cpp

@@ -47,6 +47,7 @@ bool ReaderWriter::acceptsExtension(const std::string& extension) const
 
 void ReaderWriter::supportsProtocol(const std::string& fmt, const std::string& description)
 {
+    Registry::instance()->registerProtocol(fmt);
     _supportedProtocols[convertToLowerCase(fmt)] = description;
 }
 

src/osgDB/Registry.cpp

@@ -331,6 +331,9 @@ Registry::Registry()
     addFileExtensionAlias("pgm", "pnm");
     addFileExtensionAlias("ppm", "pnm");
     
+    // register http-protocol, so the curl can handle it, if necessary
+    registerProtocol("http"); 
+    
 }
 
 
@@ -2092,3 +2095,15 @@ SharedStateManager* Registry::getOrCreateSharedStateManager()
     
     return _sharedStateManager.get();
 }
+
+
+void Registry::registerProtocol(const std::string& protocol) 
+{  
+    _registeredProtocols.insert( convertToLowerCase(protocol) ); 
+}
+        
+bool Registry::isProtocolRegistered(const std::string& protocol) 
+{ 
+    return (_registeredProtocols.find( convertToLowerCase(protocol) ) != _registeredProtocols.end()); 
+}
+