From 0757761ab0654219e18f416d38886b8ae619a071 Mon Sep 17 00:00:00 2001
From: bruceperens <bruceperens@01035d8c-6547-0410-b346-abe4f91aad63>
Date: Sun, 9 Mar 2014 22:07:21 +0000
Subject: [PATCH] Connect ready() to ALSA. Fix pedantic bug in alsa.cpp .

git-svn-id: https://svn.code.sf.net/p/freetel/code@1421 01035d8c-6547-0410-b346-abe4f91aad63
---
 freedv-server/source/platform/linux/alsa.cpp     |  2 +-
 .../source/platform/linux/audio_in_alsa.cpp      | 16 +++++++++++-----
 .../source/platform/linux/audio_out_alsa.cpp     | 15 +++++++++++----
 3 files changed, 23 insertions(+), 10 deletions(-)

diff --git a/freedv-server/source/platform/linux/alsa.cpp b/freedv-server/source/platform/linux/alsa.cpp
index 792c3d4e..5dface70 100644
--- a/freedv-server/source/platform/linux/alsa.cpp
+++ b/freedv-server/source/platform/linux/alsa.cpp
@@ -70,4 +70,4 @@ namespace FreeDV {
   
     return stream;
   }
-};
+}
diff --git a/freedv-server/source/platform/linux/audio_in_alsa.cpp b/freedv-server/source/platform/linux/audio_in_alsa.cpp
index 808136e0..084581f4 100644
--- a/freedv-server/source/platform/linux/audio_in_alsa.cpp
+++ b/freedv-server/source/platform/linux/audio_in_alsa.cpp
@@ -2,6 +2,7 @@
 
 #include "drivers.h"
 #include <alsa/asoundlib.h>
+#include <sys/ioctl.h>
 #include <sstream>
 #include <stdexcept>
 
@@ -15,12 +16,12 @@ namespace FreeDV {
 
   public:
 
-	/// Instantiate the audio sink.
+	/// Instantiate the ALSA audio input.
   		AudioInALSA(const char * parameters);
 		~AudioInALSA();
 
-	/// Return the number of audio samples the device can handle in
-	/// a write without blocking.
+	/// Return the number of audio samples the device can provide in
+	/// a read without blocking.
         virtual std::size_t
 		ready();
 
@@ -48,9 +49,9 @@ namespace FreeDV {
 
   AudioInALSA::~AudioInALSA()
   {
+    snd_pcm_close(handle);
   }
 
-  // Read audio into the "short" type.
   std::size_t
   AudioInALSA::read16(std::int16_t * array, std::size_t length)
   {
@@ -72,7 +73,12 @@ namespace FreeDV {
   std::size_t
   AudioInALSA::ready()
   {
-    return SIZE_MAX;
+    snd_pcm_sframes_t	available = 0;
+
+    if ( (available = snd_pcm_avail(handle)) <= 0 )
+      return available;
+    else
+      return 0;
   }
 
   static bool
diff --git a/freedv-server/source/platform/linux/audio_out_alsa.cpp b/freedv-server/source/platform/linux/audio_out_alsa.cpp
index af12e0c0..623dd234 100644
--- a/freedv-server/source/platform/linux/audio_out_alsa.cpp
+++ b/freedv-server/source/platform/linux/audio_out_alsa.cpp
@@ -2,20 +2,21 @@
 
 #include "drivers.h"
 #include <alsa/asoundlib.h>
+#include <sys/ioctl.h>
 #include <sstream>
 #include <stdexcept>
 
 namespace FreeDV {
   std::ostream & ALSAEnumerate(std::ostream & stream, snd_pcm_stream_t mode);
 
-  /// Audio output "sink", discards the audio, for testing.
+  /// Audio output "ALSA", Uses the Linux ALSA Audio API.
   class AudioOutALSA : public AudioOutput {
   private:
     snd_pcm_t * handle;
 
   public:
 
-	/// Instantiate the audio sink.
+	/// Instantiate the audio output.
   		AudioOutALSA(const char * parameters);
 		~AudioOutALSA();
 
@@ -24,7 +25,7 @@ namespace FreeDV {
         virtual std::size_t
 		ready();
 
-        /// Write audio into the "short" type.
+        /// Write audio from the "short" type.
 	virtual std::size_t
 		write16(const std::int16_t * array, std::size_t length);
   };
@@ -48,6 +49,7 @@ namespace FreeDV {
 
   AudioOutALSA::~AudioOutALSA()
   {
+    snd_pcm_close(handle);
   }
 
   // Write audio into the "short" type.
@@ -72,7 +74,12 @@ namespace FreeDV {
   std::size_t
   AudioOutALSA::ready()
   {
-    return SIZE_MAX;
+    snd_pcm_sframes_t	available = 0;
+
+    if ( (available = snd_pcm_avail(handle)) <= 0 )
+      return available;
+    else
+      return 0;
   }
 
   static bool
-- 
2.25.1