Allow to specify pre-allocated buffer in audicore.WaveFile

It lets us re-use the same buffer for playing multiple files.
This also allows us to control the size of the buffer. Half of the
buffer will be used for the fist, and half for the second internal
buffer.

1 files changed, 16 insertions, 6 deletions

diff --git a/shared-bindings/audiocore/WaveFile.c b/shared-bindings/audiocore/WaveFile.c
index 4c1993b7c..7398353b0 100644
--- a/shared-bindings/audiocore/WaveFile.c
+++ b/shared-bindings/audiocore/WaveFile.c
@@ -39,13 +39,15 @@
 //| ========================================================
 //|
 //| A .wav file prepped for audio playback. Only mono and stereo files are supported. Samples must
-//| be 8 bit unsigned or 16 bit signed.
+//| be 8 bit unsigned or 16 bit signed. If a buffer is provided, it will be used instead of allocating
+//| an internal buffer.
 //|
-//| .. class:: WaveFile(file)
+//| .. class:: WaveFile(file[, buffer])
 //|
 //|   Load a .wav file for playback with `audioio.AudioOut` or `audiobusio.I2SOut`.
 //|
 //|   :param typing.BinaryIO file: Already opened wave file
+//|   :param bytearray buffer: Optional pre-allocated buffer
 //|
 //|   Playing a wave file from flash::
 //|
@@ -68,15 +70,23 @@
 //|     print("stopped")
 //|
 STATIC mp_obj_t audioio_wavefile_make_new(const mp_obj_type_t *type, size_t n_args, const mp_obj_t *args, mp_map_t *kw_args) {
-    mp_arg_check_num(n_args, kw_args, 1, 1, false);
+    mp_arg_check_num(n_args, kw_args, 1, 2, false);
 
     audioio_wavefile_obj_t *self = m_new_obj(audioio_wavefile_obj_t);
     self->base.type = &audioio_wavefile_type;
-    if (MP_OBJ_IS_TYPE(args[0], &mp_type_fileio)) {
-        common_hal_audioio_wavefile_construct(self, MP_OBJ_TO_PTR(args[0]));
-    } else {
+    if (!MP_OBJ_IS_TYPE(args[0], &mp_type_fileio)) {
         mp_raise_TypeError(translate("file must be a file opened in byte mode"));
     }
+    uint8_t *buffer = NULL;
+    size_t buffer_size = 0;
+    if (n_args >= 2) {
+        mp_buffer_info_t bufinfo;
+        mp_get_buffer_raise(args[1], &bufinfo, MP_BUFFER_WRITE);
+        buffer = bufinfo.buf;
+        buffer_size = bufinfo.len;
+    }
+    common_hal_audioio_wavefile_construct(self, MP_OBJ_TO_PTR(args[0]),
+                                          buffer, buffer_size);
 
     return MP_OBJ_FROM_PTR(self);
 }