Houston, we have a trunk.

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@3122 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 124 insertions, 0 deletions

diff --git a/gr-audio-alsa/src/audio_alsa_source.h b/gr-audio-alsa/src/audio_alsa_source.h
new file mode 100644
index 000000000..cc1ae1167
--- /dev/null
+++ b/gr-audio-alsa/src/audio_alsa_source.h
@@ -0,0 +1,124 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004,2006 Free Software Foundation, Inc.
+ * 
+ * This file is part of GNU Radio
+ * 
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ * 
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#ifndef INCLUDED_AUDIO_ALSA_SOURCE_H
+#define INCLUDED_AUDIO_ALSA_SOURCE_H
+
+// use new ALSA API
+#define ALSA_PCM_NEW_HW_PARAMS_API
+#define ALSA_PCM_NEW_SW_PARAMS_API
+
+#include <gr_sync_block.h>
+#include <string>
+#include <alsa/asoundlib.h>
+#include <stdexcept>
+
+class audio_alsa_source;
+typedef boost::shared_ptr<audio_alsa_source> audio_alsa_source_sptr;
+
+/*!
+ * \brief Make an ALSA audio source.
+ *
+ * \param sampling_rate	sampling rate
+ * \param dev ALSA pcm device name, e.g., "hw:0,0"
+ * \param ok_to_block  (currently ignored)
+ */
+audio_alsa_source_sptr
+audio_alsa_make_source (int sampling_rate,
+			const std::string dev = "",
+			bool ok_to_block = true);
+
+/*!
+ * \brief audio source using ALSA
+ *
+ * The source has between 1 and N input streams of floats, where N is
+ * depends on the hardware characteristics of the selected device.
+ *
+ * Output samples will be in the range [-1,1].
+ */
+class audio_alsa_source : public gr_sync_block {
+  friend audio_alsa_source_sptr
+  audio_alsa_make_source (int sampling_rate,
+			  const std::string device_name,
+			  bool ok_to_block);
+
+  // typedef for pointer to class work method
+  typedef int (audio_alsa_source::*work_t)(int noutput_items,
+					   gr_vector_const_void_star &input_items,
+					   gr_vector_void_star &output_items);
+
+  unsigned int		d_sampling_rate;
+  std::string		d_device_name;
+  snd_pcm_t            *d_pcm_handle;
+  snd_pcm_hw_params_t  *d_hw_params;
+  snd_pcm_sw_params_t  *d_sw_params;
+  snd_pcm_format_t	d_format;
+  unsigned int		d_nperiods;
+  unsigned int		d_period_time_us;	// microseconds
+  snd_pcm_uframes_t	d_period_size;		// in frames
+  unsigned int		d_buffer_size_bytes;	// sizeof of d_buffer
+  char		       *d_buffer;
+  work_t	        d_worker;		// the work method to use
+  unsigned int		d_hw_nchan;		// # of configured h/w channels
+  bool			d_special_case_stereo_to_mono;
+
+  // random stats
+  int			d_noverruns;		// count of overruns
+  int			d_nsuspends;		// count of suspends
+
+  void output_error_msg (const char *msg, int err);
+  void bail (const char *msg, int err) throw (std::runtime_error);
+
+ protected:
+  audio_alsa_source (int sampling_rate, const std::string device_name,
+		     bool ok_to_block);
+
+ public:
+  ~audio_alsa_source ();
+  
+  bool check_topology (int ninputs, int noutputs);
+
+  int work (int noutput_items,
+	    gr_vector_const_void_star &input_items,
+	    gr_vector_void_star &output_items);
+
+protected:
+  bool read_buffer (void *buffer, unsigned nframes, unsigned sizeof_frame);
+
+  int work_s16 (int noutput_items,
+		gr_vector_const_void_star &input_items,
+		gr_vector_void_star &output_items);
+
+  int work_s16_2x1 (int noutput_items,
+		    gr_vector_const_void_star &input_items,
+		    gr_vector_void_star &output_items);
+
+  int work_s32 (int noutput_items,
+		gr_vector_const_void_star &input_items,
+		gr_vector_void_star &output_items);
+
+  int work_s32_2x1 (int noutput_items,
+		    gr_vector_const_void_star &input_items,
+		    gr_vector_void_star &output_items);
+};
+
+#endif /* INCLUDED_AUDIO_ALSA_SOURCE_H */