lib/igt_audio: make audio_signal_detect take const data

audio_signal_detect uses gsl_fft_real_radix2_transform which mutates the data
array. This can be surprising when calling audio_signal_detect and then read
again the data (e.g. for another check).

Instead of mutating the array, make audio_signal_detect less error-prone by
taking a const parameter. Do an internal copy before calling the gsl function.

Signed-off-by: Simon Ser <simon.ser@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/igt_audio.h b/lib/igt_audio.h
index 466e772a..d5ba1caa 100644
--- a/lib/igt_audio.h
+++ b/lib/igt_audio.h
@@ -43,7 +43,7 @@ void audio_signal_reset(struct audio_signal *signal);
 void audio_signal_fill(struct audio_signal *signal, int16_t *buffer,
 		       size_t buffer_len);
 bool audio_signal_detect(struct audio_signal *signal, int sampling_rate,
-			 int channel, double *data, size_t data_len);
+			 int channel, const double *samples, size_t samples_len);
 size_t audio_extract_channel_s32_le(double *dst, size_t dst_cap,
 				    int32_t *src, size_t src_len,
 				    int n_channels, int channel);