zynaddsubfx

commit 4de1f117af65e3c6a8d13f73e5794adb9d4b2ee1
parent 65cf27fcc10594d85029537581588f0cb06e921b
Author: Hans Petter Selasky <hps@selasky.org>
Date:   Tue, 28 Oct 2014 17:53:39 +0100

Improve OSS support
- Remove use of obsolete SNDCTL_DSP_SAMPLESIZE ioctl.
- Add support for 32-bit sample size. Mostly useful for recording.
- Fix sample endianness in case of big endian. Currently little endian
was always specified which is not correct for big endian systems. Use
native ending if such audio format macros exist.

Signed-off-by: Hans Petter Selasky <hps@selasky.org>

Diffstat:
M
src/Nio/OssEngine.cpp
 | 
58
+++++++++++++++++++++++++++++++++++++++++++++++-----------
M
src/Nio/OssEngine.h
 | 
7
++++++-

2 files changed, 53 insertions(+), 12 deletions(-)
diff --git a/src/Nio/OssEngine.cpp b/src/Nio/OssEngine.cpp
@@ -187,15 +187,16 @@ OssEngine::OssEngine()
     midi.handle  = -1;
     audio.handle = -1;
 
-    audio.smps = new short[synth->buffersize * 2];
-    memset(audio.smps, 0, synth->bufferbytes);
+    /* allocate worst case audio buffer */
+    audio.smps.ps32 = new int[synth->buffersize * 2];
+    memset(audio.smps.ps32, 0, sizeof(int) * synth->buffersize * 2);
     memset(&midi.state, 0, sizeof(midi.state));
 }
 
 OssEngine::~OssEngine()
 {
     Stop();
-    delete [] audio.smps;
+    delete [] audio.smps.ps32;
 }
 
 bool OssEngine::openAudio()
@@ -203,10 +204,8 @@ bool OssEngine::openAudio()
     if(audio.handle != -1)
         return true;  //already open
 
-    int snd_bitsize    = 16;
     int snd_fragment   = 0x00080009; //fragment size (?);
     int snd_stereo     = 1; //stereo;
-    int snd_format     = AFMT_S16_LE;
     int snd_samplerate = synth->samplerate;
 
     const char *device = getenv("DSP_DEVICE");
@@ -221,10 +220,37 @@ bool OssEngine::openAudio()
         return false;
     }
     ioctl(audio.handle, SNDCTL_DSP_RESET, NULL);
-    ioctl(audio.handle, SNDCTL_DSP_SETFMT, &snd_format);
+
+    /* Figure out the correct format first */
+#if defined(AFMT_S16_NE) && defined(AFMT_S32_NE)
+    int snd_format32 = AFMT_S32_NE;
+    int snd_format16 = AFMT_S16_NE;
+#elif defined(BYTE_ORDER) && defined(LITTLE_ENDIAN)
+#if BYTE_ORDER == LITTLE_ENDIAN
+    int snd_format32 = AFMT_S32_LE;
+    int snd_format16 = AFMT_S16_LE;
+#else
+    int snd_format32 = AFMT_S32_BE;
+    int snd_format16 = AFMT_S16_BE;
+#endif
+#else
+    int snd_format32 = AFMT_S32_LE;
+    int snd_format16 = AFMT_S16_LE;
+#endif
+
+    if (ioctl(audio.handle, SNDCTL_DSP_SETFMT, &snd_format32) == 0) {
+	audio.is32bit = true;
+    } else if (ioctl(audio.handle, SNDCTL_DSP_SETFMT, &snd_format16) == 0) {
+	audio.is32bit = false;
+    } else {
+	cerr << "ERROR - I cannot set DSP format for "
+	     << device << '.' << endl;
+	close(audio.handle);
+	audio.handle = -1;
+	return false;
+    }
     ioctl(audio.handle, SNDCTL_DSP_STEREO, &snd_stereo);
     ioctl(audio.handle, SNDCTL_DSP_SPEED, &snd_samplerate);
-    ioctl(audio.handle, SNDCTL_DSP_SAMPLESIZE, &snd_bitsize);
     ioctl(audio.handle, SNDCTL_DSP_SETFRAGMENT, &snd_fragment);
 
     pthread_attr_t attr;
@@ -380,8 +406,13 @@ void *OssEngine::audioThreadCb()
                 if(r > 1.0f)
                     r = 1.0f;
 
-            audio.smps[i * 2]     = (short int) (l * 32767.0f);
-            audio.smps[i * 2 + 1] = (short int) (r * 32767.0f);
+	    if (audio.is32bit) {
+		audio.smps.ps32[i * 2]     = (int) (l * 2147483647.0f);
+		audio.smps.ps32[i * 2 + 1] = (int) (r * 2147483647.0f);
+	    } else {	/* 16bit */
+		audio.smps.ps16[i * 2]     = (short int) (l * 32767.0f);
+		audio.smps.ps16[i * 2 + 1] = (short int) (r * 32767.0f);
+	    }
         }
 
         int error;
@@ -390,8 +421,13 @@ void *OssEngine::audioThreadCb()
             int handle = audio.handle;
             if(handle == -1)
                 goto done;
-            /* 2x because is 16 bit, again 2x because it is stereo */
-            error = write(handle, audio.smps, synth->buffersize * 4);
+	    if (audio.is32bit) {
+		/* 4x because it is 32 bit, again 2x because it is stereo */
+		error = write(handle, audio.smps.ps32, synth->buffersize * 8);
+	    } else {
+		/* 2x because it is 16 bit, again 2x because it is stereo */
+		error = write(handle, audio.smps.ps16, synth->buffersize * 4);
+	    }
         } while (error == -1 && errno == EINTR);
 
         if(error == -1)
diff --git a/src/Nio/OssEngine.h b/src/Nio/OssEngine.h
@@ -74,8 +74,13 @@ class OssEngine:public AudioOut, MidiIn
 
         struct audio {
             int handle;
-            short int *smps; //Samples to be sent to soundcard
+            union {
+                /* Samples to be sent to soundcard */
+                short int *ps16;
+                int *ps32;
+            } smps;
             bool en;
+            bool is32bit;
         } audio;
 
         //Midi