first working multichannel source

lib/fcd/fcd_source.cc

@@ -28,33 +28,38 @@
 
 #include <fcd_source.h>
 
+#include <osmosdr_arg_helpers.h>
+
 using namespace boost::assign;
 
 fcd_source_sptr make_fcd_source(const std::string &args)
 {
-    return gnuradio::get_initial_sptr(new fcd_source(args));
+  return gnuradio::get_initial_sptr(new fcd_source(args));
 }
 
 fcd_source::fcd_source(const std::string &args) :
-    gr_hier_block2("fcd_source",
-                   gr_make_io_signature (0, 0, 0),
-                   gr_make_io_signature (1, 1, sizeof (gr_complex)))
+  gr_hier_block2("fcd_source",
+                 gr_make_io_signature (0, 0, 0),
+                 gr_make_io_signature (1, 1, sizeof (gr_complex)))
 {
-    std::string device_name = args;
+  std::string dev_name;
+  unsigned int dev_index = 0;
 
-    if ( device_name.empty() )
-    {
-        std::vector< std::string > devices = fcd_source::get_devices();
+  dict_t dict = params_to_dict(args);
 
-        if ( devices.size() )
-            device_name = devices.front(); // pick first available device
-        else
-            throw std::runtime_error("no FUNcube Dongle device found");
-    }
+  if (dict.count("fcd"))
+    dev_index = boost::lexical_cast< unsigned int >( dict["fcd"] );
+
+  std::vector< std::string > devices = fcd_source::get_devices();
 
-    _src = fcd_make_source_c( device_name );
+  if ( devices.size() )
+    dev_name = devices[dev_index];
+  else
+    throw std::runtime_error("No FunCube Dongle found.");
 
-    connect( _src, 0, self(), 0 );
+  _src = fcd_make_source_c( dev_name );
+
+  connect( _src, 0, self(), 0 );
 }
 
 fcd_source::~fcd_source()
@@ -63,42 +68,42 @@ fcd_source::~fcd_source()
 
 std::vector< std::string > fcd_source::get_devices()
 {
-    std::vector< std::string > devices;
+  std::vector< std::string > devices;
 
-    std::string line;
-    std::ifstream cards( "/proc/asound/cards" );
-    if ( cards.is_open() )
+  std::string line;
+  std::ifstream cards( "/proc/asound/cards" );
+  if ( cards.is_open() )
+  {
+    while ( cards.good() )
     {
-        while ( cards.good() )
-        {
-            getline (cards, line);
-
-            if ( line.find( "USB-Audio - FUNcube Dongle" ) != std::string::npos )
-            {
-                int id;
-                std::istringstream( line ) >> id;
+      getline (cards, line);
 
-                std::ostringstream hw_id;
-                hw_id << "hw:" << id; // build alsa identifier
+      if ( line.find( "USB-Audio - FUNcube Dongle" ) != std::string::npos )
+      {
+        int id;
+        std::istringstream( line ) >> id;
 
-                devices += hw_id.str();
-            }
-        }
+        std::ostringstream hw_id;
+        hw_id << "hw:" << id; // build alsa identifier
 
-        cards.close();
+        devices += hw_id.str();
+      }
     }
 
-    return devices;
+    cards.close();
+  }
+
+  return devices;
 }
 
 gr_basic_block_sptr fcd_source::self()
 {
-    return gr_hier_block2::self();
+  return gr_hier_block2::self();
 }
 
 std::string fcd_source::name()
 {
-    return "FUNcube Dongle";
+  return "FUNcube Dongle";
 }
 
 size_t fcd_source::get_num_channels( void )
@@ -223,4 +228,3 @@ std::string fcd_source::get_antenna( size_t chan )
 {
   return "ANT";
 }
-

lib/fcd/fcd_source.h

@@ -32,8 +32,9 @@ typedef boost::shared_ptr< fcd_source > fcd_source_sptr;
 
 fcd_source_sptr make_fcd_source( const std::string & args = "" );
 
-class fcd_source : public gr_hier_block2,
-                     public osmosdr_src_iface
+class fcd_source :
+    public gr_hier_block2,
+    public osmosdr_src_iface
 {
 private:
   friend fcd_source_sptr make_fcd_source(const std::string &args);

lib/osmosdr/osmosdr_control.cc

@@ -30,12 +30,12 @@ using namespace boost::assign;
 
 osmosdr_control::osmosdr_control(const std::string &args)
 {
-    /* lookup acm control channel device name for a given alsa device name */
+  /* lookup acm control channel device name for a given alsa device name */
 
-    /*
-        if (args.empty())
-            pick first available device or throw an exception();
-    */
+  /*
+  if (args.empty())
+    pick first available device or throw an exception();
+  */
 }
 
 osmosdr_control::~osmosdr_control()
@@ -48,46 +48,46 @@ osmosdr_control::~osmosdr_control()
 */
 std::vector< std::string > osmosdr_control::find_devices()
 {
-    std::vector< std::string > devices;
+  std::vector< std::string > devices;
 
-    std::string line;
-    std::ifstream cards( "/proc/asound/cards" );
-    if ( cards.is_open() )
+  std::string line;
+  std::ifstream cards( "/proc/asound/cards" );
+  if ( cards.is_open() )
+  {
+    while ( cards.good() )
     {
-        while ( cards.good() )
-        {
-            getline (cards, line);
+      getline (cards, line);
 
-            if ( line.find( "USB-Audio - OsmoSDR" ) != std::string::npos )
-            {
-                int id;
-                std::istringstream( line ) >> id;
+      if ( line.find( "USB-Audio - OsmoSDR" ) != std::string::npos )
+      {
+        int id;
+        std::istringstream( line ) >> id;
 
-                std::ostringstream hw_id;
-                hw_id << "hw:" << id; // build alsa identifier
+        std::ostringstream hw_id;
+        hw_id << "hw:" << id; // build alsa identifier
 
-                devices += hw_id.str();
-            }
-        }
-
-        cards.close();
+        devices += hw_id.str();
+      }
     }
 
-    return devices;
+    cards.close();
+  }
+
+  return devices;
 }
 
 std::string osmosdr_control::audio_dev_name()
 {
-    return "hw:1";
+  return "hw:1";
 }
 
 std::string osmosdr_control::control_dev_name()
 {
-    return "/dev/ttyUSB0";
+  return "/dev/ttyUSB0";
 }
 
 osmosdr_rx_control::osmosdr_rx_control(const std::string &args) :
-    osmosdr_control(args)
+  osmosdr_control(args)
 {
 }
 
@@ -96,7 +96,7 @@ osmosdr_rx_control::~osmosdr_rx_control()
 }
 
 osmosdr_tx_control::osmosdr_tx_control(const std::string &args) :
-    osmosdr_control(args)
+  osmosdr_control(args)
 {
 }
 

lib/osmosdr/osmosdr_snk_c.cc

@@ -27,7 +27,7 @@
 #include "config.h"
 #endif
 
-#include <osmosdr_snk_c.h>
+#include "osmosdr_snk_c.h"
 #include <gr_io_signature.h>
 #include <gr_audio_sink.h>
 #include <gr_complex_to_xxx.h>
@@ -49,7 +49,7 @@ osmosdr_make_snk_c (const std::string &args)
  * output signatures are used by the runtime system to
  * check that a valid number and type of inputs and outputs
  * are connected to this block.  In this case, we accept
- * only 1 input and 1 output.
+ * only 1 input and 0 output.
  */
 static const int MIN_IN = 1;	// mininum number of input streams
 static const int MAX_IN = 1;	// maximum number of input streams
@@ -65,18 +65,18 @@ osmosdr_snk_c::osmosdr_snk_c (const std::string & args)
         gr_make_io_signature (MIN_OUT, MAX_OUT, sizeof (gr_complex))),
     osmosdr_tx_control(args)
 {
-    throw std::runtime_error("FIXME: OsmoSDR sink is not yet implemented");
+  throw std::runtime_error("FIXME: OsmoSDR sink is not yet implemented");
 
-    /* Audio sink; sample rate is 96kHz by default */
-    audio_sink::sptr snk = audio_make_sink(96000, audio_dev_name(), true);
+  /* Audio sink; sample rate is 96kHz by default */
+  audio_sink::sptr snk = audio_make_sink(96000, audio_dev_name(), true);
 
-    gr_complex_to_real_sptr real_part = gr_make_complex_to_real(1);
-    gr_complex_to_imag_sptr imag_part = gr_make_complex_to_imag(1);
+  gr_complex_to_real_sptr real_part = gr_make_complex_to_real(1);
+  gr_complex_to_imag_sptr imag_part = gr_make_complex_to_imag(1);
 
-    connect(self(), 0, real_part, 0);
-    connect(self(), 0, imag_part, 0);
-    connect(imag_part, 0, snk, 0); /* Left is I */
-    connect(real_part, 0, snk, 1); /* Right is Q */
+  connect(self(), 0, real_part, 0);
+  connect(self(), 0, imag_part, 0);
+  connect(imag_part, 0, snk, 0); /* Left is I */
+  connect(real_part, 0, snk, 1); /* Right is Q */
 }
 
 /*

lib/osmosdr/osmosdr_snk_c.h

@@ -54,8 +54,9 @@ OSMOSDR_API osmosdr_snk_c_sptr osmosdr_make_snk_c (const std::string & args = ""
  *
  * This uses the preferred technique: subclassing gr_hier_block2.
  */
-class OSMOSDR_API osmosdr_snk_c : public gr_hier_block2,
-                                   public osmosdr_tx_control
+class OSMOSDR_API osmosdr_snk_c :
+    public gr_hier_block2,
+    public osmosdr_tx_control
 {
 private:
   // The friend declaration allows osmosdr_make_snk_c to

lib/osmosdr/osmosdr_src_c.cc

@@ -31,6 +31,8 @@
 #include <gr_audio_source.h>
 #include <gr_float_to_complex.h>
 
+#include <osmosdr_arg_helpers.h>
+
 /*
  * Create a new instance of osmosdr_src_c and return
  * a boost shared_ptr.  This is effectively the public constructor.
@@ -41,38 +43,24 @@ osmosdr_make_src_c (const std::string &args)
   return gnuradio::get_initial_sptr(new osmosdr_src_c (args));
 }
 
-/*
- * Specify constraints on number of input and output streams.
- * This info is used to construct the input and output signatures
- * (2nd & 3rd args to gr_block's constructor).  The input and
- * output signatures are used by the runtime system to
- * check that a valid number and type of inputs and outputs
- * are connected to this block.  In this case, we accept
- * only 1 input and 1 output.
- */
-static const int MIN_IN = 0;	// mininum number of input streams
-static const int MAX_IN = 0;	// maximum number of input streams
-static const int MIN_OUT = 1;	// minimum number of output streams
-static const int MAX_OUT = 1;	// maximum number of output streams
-
 /*
  * The private constructor
  */
 osmosdr_src_c::osmosdr_src_c (const std::string &args)
   : gr_hier_block2 ("osmosdr_src_c",
-        gr_make_io_signature (MIN_IN, MAX_IN, sizeof (gr_complex)),
-        gr_make_io_signature (MIN_OUT, MAX_OUT, sizeof (gr_complex))),
+        gr_make_io_signature (0, 0, sizeof (gr_complex)),
+        args_to_io_signature(args)),
     osmosdr_rx_control(args)
 {
-    /* Audio source; sample rate is 500kHz by default */
-    audio_source::sptr src = audio_make_source(500000, audio_dev_name(), true);
+  /* Audio source; sample rate is 500kHz by default */
+  audio_source::sptr src = audio_make_source(500000, audio_dev_name(), true);
 
-    /* block to convert stereo audio to a complex stream */
-    gr_float_to_complex_sptr f2c = gr_make_float_to_complex(1);
+  /* block to convert stereo audio to a complex stream */
+  gr_float_to_complex_sptr f2c = gr_make_float_to_complex(1);
 
-    connect(src, 0, f2c, 0); /* Left is I */
-    connect(src, 1, f2c, 1); /* Right is Q */
-    connect(f2c, 0, self(), 0);
+  connect(src, 0, f2c, 0); /* Left is I */
+  connect(src, 1, f2c, 1); /* Right is Q */
+  connect(f2c, 0, self(), 0);
 }
 
 /*

lib/osmosdr/osmosdr_src_c.h

@@ -54,8 +54,9 @@ OSMOSDR_API osmosdr_src_c_sptr osmosdr_make_src_c (const std::string & args = ""
  *
  * \sa osmosdr_sink_c for a version that subclasses gr_hier_block2.
  */
-class OSMOSDR_API osmosdr_src_c : public gr_hier_block2,
-                                     public osmosdr_rx_control
+class OSMOSDR_API osmosdr_src_c :
+    public gr_hier_block2,
+    public osmosdr_rx_control
 {
 private:
   // The friend declaration allows osmosdr_make_src_c to

lib/osmosdr_arg_helpers.h

@@ -31,6 +31,9 @@
 #include <boost/tokenizer.hpp>
 #include <boost/foreach.hpp>
 
+typedef std::map< std::string, std::string > dict_t;
+typedef std::pair<std::string, std::string> pair_t;
+
 inline std::vector< std::string > args_to_vector( const std::string &args )
 {
   std::vector< std::string > result;
@@ -59,25 +62,91 @@ inline std::vector< std::string > params_to_vector( const std::string &params )
   return result;
 }
 
-typedef std::map< std::string, std::string > dict_t;
+inline pair_t param_to_pair( const std::string &param )
+{
+  pair_t result;
+
+  std::size_t pos = param.find('=');
+  if(pos != std::string::npos)
+  {
+    result.first = param.substr(0, pos);
+    result.second = param.substr(pos + 1);
+  }
+  else
+  {
+    result.first = param;
+    result.second = "";
+  }
+
+  return result;
+}
 
 inline dict_t params_to_dict( const std::string &params )
 {
   dict_t result;
 
   std::vector< std::string > param_list = params_to_vector( params );
-  BOOST_FOREACH(std::string param, param_list) {
-    std::cout << "D'" << param << "'" << std::endl;
+  BOOST_FOREACH(std::string param, param_list)
+  {
+    pair_t nchan = param_to_pair( param );
+    std::string value = nchan.second;
+    if (value.length() && value[0] == '\'' && value[ value.length() - 1 ] == '\'')
+      value = value.substr(1, value.length() - 1);
+    result[ nchan.first ] = nchan.second;
   }
 
   return result;
 }
 
+struct is_nchan_argument
+{
+  bool operator ()(const std::string &str)
+  {
+    return str.find("nchan=") == 0;
+  }
+};
+
 inline gr_io_signature_sptr args_to_io_signature( const std::string &args )
 {
+  size_t max_nchan = 0;
+  size_t dev_nchan = 0;
   std::vector< std::string > arg_list = args_to_vector( args );
 
-  const size_t nchan = std::max<size_t>(arg_list.size(), 1);
+  BOOST_FOREACH( std::string arg, arg_list )
+  {
+    if ( arg.find( "nchan=" ) == 0 ) // try to parse global nchan value
+    {
+      pair_t pair = param_to_pair( arg );
+      max_nchan = boost::lexical_cast<size_t>( pair.second );
+    }
+  }
+
+  arg_list.erase( std::remove_if( // remove any global nchan tokens
+                    arg_list.begin(),
+                    arg_list.end(),
+                    is_nchan_argument() ),
+                  arg_list.end() );
+
+  // try to parse device specific nchan values, assume 1 channel if none given
+
+  BOOST_FOREACH( std::string arg, arg_list )
+  {
+    dict_t dict = params_to_dict(arg);
+    if (dict.count("nchan"))
+    {
+      dev_nchan += boost::lexical_cast<size_t>( dict["nchan"] );
+    }
+    else // no channels given via args
+    {
+      dev_nchan++; // assume one channel
+    }
+  }
+
+  // if at least one nchan was given, perform a sanity check
+  if ( max_nchan && dev_nchan && max_nchan != dev_nchan )
+    throw std::runtime_error("Wrong device arguments specified. Missing nchan?");
+
+  const size_t nchan = std::max<size_t>(dev_nchan, 1); // assume at least one
   return gr_make_io_signature(nchan, nchan, sizeof(gr_complex));
 }
 

lib/osmosdr_sink_c_impl.cc

@@ -47,12 +47,12 @@ osmosdr_make_sink_c (const std::string &args)
  * output signatures are used by the runtime system to
  * check that a valid number and type of inputs and outputs
  * are connected to this block.  In this case, we accept
- * only 1 input and 1 output.
+ * only 1 input and 0 output.
  */
-static const int MIN_IN = 0;	// mininum number of input streams
-static const int MAX_IN = 0;	// maximum number of input streams
-static const int MIN_OUT = 1;	// minimum number of output streams
-static const int MAX_OUT = 1;	// maximum number of output streams
+static const int MIN_IN = 1;	// mininum number of input streams
+static const int MAX_IN = 1;	// maximum number of input streams
+static const int MIN_OUT = 0;	// minimum number of output streams
+static const int MAX_OUT = 0;	// maximum number of output streams
 
 /*
  * The private constructor

lib/osmosdr_source_c_impl.cc

@@ -30,6 +30,22 @@
 #include <osmosdr_source_c_impl.h>
 #include <gr_io_signature.h>
 
+#ifdef ENABLE_OSMOSDR
+#include <osmosdr_src_c.h>
+#endif
+
+#ifdef ENABLE_FCD
+#include <fcd_source.h>
+#endif
+
+#ifdef ENABLE_RTL
+#include <rtl_source_c.h>
+#endif
+
+#ifdef ENABLE_UHD
+#include <uhd_source_c.h>
+#endif
+
 #include <osmosdr_arg_helpers.h>
 
 /*
@@ -50,34 +66,65 @@ osmosdr_source_c_impl::osmosdr_source_c_impl (const std::string &args)
         gr_make_io_signature (0, 0, 0),
         args_to_io_signature(args))
 {
-  std::vector< std::string > arg_list = args_to_vector(args);
+  size_t channel = 0;
 
-  std::cout << "arg_list.size: " << arg_list.size() << std::endl;
+  BOOST_FOREACH(std::string arg, args_to_vector(args)) {
 
-  BOOST_FOREACH(std::string arg, arg_list) {
     dict_t dict = params_to_dict(arg);
 
-    std::cout << "" << std::endl;
-    BOOST_FOREACH( dict_t::value_type &entry, dict )
-        std::cout << "'" << entry.first << "' '" << entry.second << "'" << std::endl;
-  }
+//    std::cout << std::endl;
+//    BOOST_FOREACH( dict_t::value_type &entry, dict )
+//      std::cout << "'" << entry.first << "' = '" << entry.second << "'" << std::endl;
 
-  for ( int i = 0; i < 1; i++ ) {
-    std::string arg = boost::lexical_cast<std::string>(i);
+#ifdef ENABLE_OSMOSDR
+    if ( dict.count("osmosdr") ) {
+      osmosdr_src_c_sptr src = osmosdr_make_src_c( arg );
 
-    rtl_source_c_sptr src = make_rtl_source_c( arg );
+//      for (size_t i = 0; i < src->get_num_channels(); i++)
+//        connect(src, i, self(), channel++);
 
-    connect(src, 0, self(), i);
+//      _srcs.push_back( (osmosdr_src_iface *)src.get() ); // FIXME: implement
+    }
+#endif
+
+#ifdef ENABLE_FCD
+    if ( dict.count("fcd") ) {
+      fcd_source_sptr src = make_fcd_source( arg );
+      connect(src, 0, self(), channel++);
+      _srcs.push_back( (osmosdr_src_iface *)src.get() );
+    }
+#endif
+
+#ifdef ENABLE_RTL
+    if ( dict.count("rtl") ) {
+      rtl_source_c_sptr src = make_rtl_source_c( arg );
+      connect(src, 0, self(), channel++);
+      _srcs.push_back( (osmosdr_src_iface *)src.get() );
+    }
+#endif
 
-    _srcs.push_back( src );
+#ifdef ENABLE_UHD
+    if ( dict.count("uhd") ) {
+      uhd_source_c_sptr src = make_uhd_source_c( arg );
+
+      for (size_t i = 0; i < src->get_num_channels(); i++)
+        connect(src, i, self(), channel++);
+
+      _srcs.push_back( (osmosdr_src_iface *)src.get() );
+    }
+#endif
   }
+
+  if (!_srcs.size())
+    throw std::runtime_error("No devices specified via device arguments.");
 }
 
 size_t osmosdr_source_c_impl::get_num_channels()
 {
   size_t channels = 0;
 
-  channels = _srcs[0]->get_num_channels();
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    channels += dev->get_num_channels();
 
   return channels;
 }
@@ -89,8 +136,12 @@ osmosdr::meta_range_t osmosdr_source_c_impl::get_sample_rates()
 
 double osmosdr_source_c_impl::set_sample_rate(double rate)
 {
-  return _srcs[0]->set_sample_rate(rate);
-//  return rate;
+  double sample_rate = 0;
+
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+        sample_rate = dev->set_sample_rate(rate);
+
+  return sample_rate;
 }
 
 double osmosdr_source_c_impl::get_sample_rate()
@@ -100,76 +151,165 @@ double osmosdr_source_c_impl::get_sample_rate()
 
 osmosdr::freq_range_t osmosdr_source_c_impl::get_freq_range( size_t chan )
 {
-  return _srcs[chan]->get_freq_range( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_freq_range( chan );
+
+  return osmosdr::freq_range_t();
 }
 
 double osmosdr_source_c_impl::set_center_freq( double freq, size_t chan )
 {
-  return _srcs[chan]->set_center_freq( freq, chan );
-//  return freq;
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->set_center_freq( freq, chan );
+
+  return 0;
 }
 
 double osmosdr_source_c_impl::get_center_freq( size_t chan )
 {
-  return _srcs[chan]->get_center_freq( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_center_freq( chan );
+
+  return 0;
 }
 
 double osmosdr_source_c_impl::set_freq_corr( double ppm, size_t chan )
 {
-  return _srcs[chan]->set_freq_corr( ppm, chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->set_freq_corr( ppm, chan );
+
+  return 0;
 }
 
 double osmosdr_source_c_impl::get_freq_corr( size_t chan )
 {
-  return _srcs[chan]->get_freq_corr( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_freq_corr( chan );
+
+  return 0;
 }
 
 std::vector<std::string> osmosdr_source_c_impl::get_gain_names( size_t chan )
 {
-  return _srcs[chan]->get_gain_names( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_gain_names( chan );
+
+  return std::vector< std::string >();
 }
 
 osmosdr::gain_range_t osmosdr_source_c_impl::get_gain_range( size_t chan )
 {
-  return _srcs[chan]->get_gain_range( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_gain_range( chan );
+
+  return osmosdr::gain_range_t();
 }
 
 osmosdr::gain_range_t osmosdr_source_c_impl::get_gain_range( const std::string & name, size_t chan )
 {
-  return _srcs[chan]->get_gain_range( name, chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_gain_range( name, chan );
+
+  return osmosdr::gain_range_t();
 }
 
 double osmosdr_source_c_impl::set_gain( double gain, size_t chan )
 {
-  return _srcs[chan]->set_gain( gain, chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->set_gain( gain, chan );
+
+  return 0;
 }
 
 double osmosdr_source_c_impl::set_gain( double gain, const std::string & name, size_t chan)
 {
-  return _srcs[chan]->set_gain( gain, name, chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->set_gain( gain, name, chan );
+
+  return 0;
 }
 
 double osmosdr_source_c_impl::get_gain( size_t chan )
 {
-  return _srcs[chan]->get_gain( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_gain( chan );
+
+  return 0;
 }
 
 double osmosdr_source_c_impl::get_gain( const std::string & name, size_t chan )
 {
-  return _srcs[chan]->get_gain( name, chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_gain( name, chan );
+
+  return 0;
 }
 
 std::vector< std::string > osmosdr_source_c_impl::get_antennas( size_t chan )
 {
-  return _srcs[chan]->get_antennas( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_antennas( chan );
+
+  return std::vector< std::string >();
 }
 
 std::string osmosdr_source_c_impl::set_antenna( const std::string & antenna, size_t chan )
 {
-  return _srcs[chan]->set_antenna( antenna, chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->set_antenna( antenna, chan );
+
+  return "";
 }
 
 std::string osmosdr_source_c_impl::get_antenna( size_t chan )
 {
-  return _srcs[chan]->get_antenna( chan );
+  size_t channel = 0;
+  BOOST_FOREACH( osmosdr_src_iface *dev, _srcs )
+    for (size_t i = 0; i < dev->get_num_channels(); i++)
+      if ( chan == channel++ )
+        return _srcs[chan]->get_antenna( chan );
+
+  return "";
 }

lib/osmosdr_source_c_impl.h

@@ -23,7 +23,7 @@
 #include <osmosdr_api.h>
 #include <osmosdr_source_c.h>
 
-#include <rtl_source_c.h>
+#include <osmosdr_src_iface.h>
 
 class OSMOSDR_API osmosdr_source_c_impl : public osmosdr_source_c
 {
@@ -60,7 +60,7 @@ private:
   friend OSMOSDR_API osmosdr_source_c_sptr osmosdr_make_source_c (const std::string & args);
 
   size_t _nchan;
-  std::vector< rtl_source_c_sptr > _srcs;
+  std::vector< osmosdr_src_iface * > _srcs;
 };
 
 #endif /* INCLUDED_OSMOSDR_SOURCE_C_IMPL_H */

lib/rtl/rtl_source_c.cc

@@ -38,6 +38,8 @@
 
 #include <rtl-sdr.h>
 
+#include <osmosdr_arg_helpers.h>
+
 using namespace boost::assign;
 
 #define BUF_SIZE (16 * 32 * 512)
@@ -59,7 +61,7 @@ make_rtl_source_c (const std::string &args)
  * output signatures are used by the runtime system to
  * check that a valid number and type of inputs and outputs
  * are connected to this block.  In this case, we accept
- * only 1 input and 1 output.
+ * only 0 input and 1 output.
  */
 static const int MIN_IN = 0;	// mininum number of input streams
 static const int MAX_IN = 0;	// maximum number of input streams
@@ -75,9 +77,12 @@ rtl_source_c::rtl_source_c (const std::string &args)
         gr_make_io_signature (MIN_OUT, MAX_OUT, sizeof (gr_complex)))
 {
   int ret;
-  unsigned int dev_index = atoi( args.c_str() );
+  unsigned int dev_index = 0;
+
+  dict_t dict = params_to_dict(args);
 
-  std::cout << "'" << args << "'" << std::endl;
+  if (dict.count("rtl"))
+    dev_index = boost::lexical_cast< unsigned int >( dict["rtl"] );
 
   _buf_num = 32;
   _buf = (unsigned short **) malloc(_buf_num * sizeof(unsigned short *));

lib/rtl/rtl_source_c.h

@@ -61,8 +61,9 @@ OSMOSDR_API rtl_source_c_sptr make_rtl_source_c (const std::string & args = "");
  * \ingroup block
  *
  */
-class OSMOSDR_API rtl_source_c : public gr_sync_block,
-                                 public osmosdr_src_iface
+class OSMOSDR_API rtl_source_c :
+    public gr_sync_block,
+    public osmosdr_src_iface
 {
 private:
   // The friend declaration allows make_rtl_source_c to

lib/uhd/uhd_source_c.cc

@@ -25,23 +25,38 @@
 
 #include <gr_io_signature.h>
 
+#include <osmosdr_arg_helpers.h>
+
 #include "uhd_source_c.h"
 
 using namespace boost::assign;
 
 uhd_source_c_sptr make_uhd_source_c(const std::string &args)
 {
-    return gnuradio::get_initial_sptr(new uhd_source_c(args));
+  return gnuradio::get_initial_sptr(new uhd_source_c(args));
 }
 
 uhd_source_c::uhd_source_c(const std::string &args) :
     gr_hier_block2("uhd_source_c",
                    gr_make_io_signature (0, 0, 0),
-                   gr_make_io_signature (1, 1, sizeof (gr_complex)))
+                   args_to_io_signature(args))
 {
-    _src = uhd_make_usrp_source( args, uhd::io_type_t::COMPLEX_FLOAT32, 1 );
+  size_t num_channels = 1;
+
+  dict_t dict = params_to_dict(args);
+
+  if (dict.count("nchan"))
+    num_channels = boost::lexical_cast< unsigned int >( dict["nchan"] );
+
+  _src = uhd_make_usrp_source( args,
+                               uhd::io_type_t::COMPLEX_FLOAT32,
+                               num_channels );
+
+  if (dict.count("subdev"))
+    _src->set_subdev_spec( dict["subdev"] );
 
-    connect( _src, 0, self(), 0 );
+  for ( size_t i = 0; i < num_channels; i++ )
+    connect( _src, i, self(), i );
 }
 
 uhd_source_c::~uhd_source_c()
@@ -50,18 +65,18 @@ uhd_source_c::~uhd_source_c()
 
 std::vector< std::string > uhd_source_c::get_devices()
 {
-    std::vector< std::string > devices;
+  std::vector< std::string > devices;
 
-    uhd::device_addr_t hint;
-    BOOST_FOREACH(uhd::device_addr_t device, uhd::device::find(hint))
-        devices += device.to_string();
+  uhd::device_addr_t hint;
+  BOOST_FOREACH(uhd::device_addr_t device, uhd::device::find(hint))
+    devices += device.to_string();
 
-    return devices;
+  return devices;
 }
 
 gr_basic_block_sptr uhd_source_c::self()
 {
-    return gr_hier_block2::self();
+  return gr_hier_block2::self();
 }
 
 std::string uhd_source_c::name()
@@ -132,7 +147,7 @@ double uhd_source_c::set_freq_corr( double ppm, size_t chan )
 
 double uhd_source_c::get_freq_corr( size_t chan )
 {
-  throw std::runtime_error( "frequency correction is not supported with UHD" );
+  return 0; // frequency correction is not supported with UHD
 }
 
 std::vector<std::string> uhd_source_c::get_gain_names( size_t chan )

lib/uhd/uhd_source_c.h

@@ -32,8 +32,9 @@ typedef boost::shared_ptr< uhd_source_c > uhd_source_c_sptr;
 
 uhd_source_c_sptr make_uhd_source_c(const std::string &args = "");
 
-class uhd_source_c : public gr_hier_block2,
-                     public osmosdr_src_iface
+class uhd_source_c :
+    public gr_hier_block2,
+    public osmosdr_src_iface
 {
 private:
   friend uhd_source_c_sptr make_uhd_source_c(const std::string &args);