From 43a94b3c623a2982403aca607c03b0cdd202fe58 Mon Sep 17 00:00:00 2001
From: Lars Immisch <lars@ibp.de>
Date: Tue, 12 Sep 2023 21:04:02 +0200
Subject: [PATCH] Add PCM.avail()

Will be used in the upcoming loopback implementation, but it is
worthwhile regardless.
---
 alsaaudio.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/alsaaudio.c b/alsaaudio.c
index a7382e9..11369de 100644
--- a/alsaaudio.c
+++ b/alsaaudio.c
@@ -1504,6 +1504,30 @@ static PyObject *alsapcm_write(alsapcm_t *self, PyObject *args)
 	return rc;
 }
 
+static PyObject *
+alsapcm_avail(alsapcm_t *self, PyObject *args)
+{
+	if (!PyArg_ParseTuple(args,":avail"))
+		return NULL;
+
+	if (!self->handle)
+	{
+		PyErr_SetString(ALSAAudioError, "PCM device is closed");
+		return NULL;
+	}
+
+	long avail = snd_pcm_avail(self->handle);
+	// if (avail < 0)
+	// {
+	// 	PyErr_Format(ALSAAudioError, "%s [%s]", snd_strerror(avail),
+	// 				 self->cardname);
+
+	// 	return NULL;
+	// }
+
+	return PyLong_FromLong(avail);
+}
+
 static PyObject *alsapcm_pause(alsapcm_t *self, PyObject *args)
 {
 	int enabled=1, res;
@@ -1649,6 +1673,7 @@ static PyMethodDef alsapcm_methods[] = {
 	{"getchannels", (PyCFunction)alsapcm_getchannels, METH_VARARGS},
 	{"read", (PyCFunction)alsapcm_read, METH_VARARGS},
 	{"write", (PyCFunction)alsapcm_write, METH_VARARGS},
+	{"avail", (PyCFunction)alsapcm_avail, METH_VARARGS},
 	{"pause", (PyCFunction)alsapcm_pause, METH_VARARGS},
 	{"drop", (PyCFunction)alsapcm_drop, METH_VARARGS},
 	{"drain", (PyCFunction)alsapcm_drain, METH_VARARGS},