From a305eb53511cf3f48f09c8b0adbf03644957476e Mon Sep 17 00:00:00 2001
From: Milanka Ringwald <mila@ringwald.ch>
Date: Wed, 17 Jan 2018 14:59:12 +0100
Subject: [PATCH] sbc: handle more errors, assert liveliness
---
src/classic/btstack_sbc_decoder_bluedroid.c | 183 +++++++++++---------
1 file changed, 100 insertions(+), 83 deletions(-)
diff --git a/src/classic/btstack_sbc_decoder_bluedroid.c b/src/classic/btstack_sbc_decoder_bluedroid.c
index b5e141552..dce55cf93 100644
--- a/src/classic/btstack_sbc_decoder_bluedroid.c
+++ b/src/classic/btstack_sbc_decoder_bluedroid.c
@@ -212,99 +212,116 @@ static void append_received_sbc_data(bludroid_decoder_state_t * state, uint8_t *
static void btstack_sbc_decoder_process_sbc_data(btstack_sbc_decoder_state_t * state, int packet_status_flag, uint8_t * buffer, int size){
bludroid_decoder_state_t * decoder_state = (bludroid_decoder_state_t*)state->decoder_state;
int input_bytes_to_process = size;
+ int keep_decoding = 1;
- while (input_bytes_to_process){
-
- // fill buffer with new data
- int bytes_free_in_buffer = SBC_MAX_FRAME_LEN - decoder_state->bytes_in_frame_buffer;
- int bytes_to_append = btstack_min(input_bytes_to_process, bytes_free_in_buffer);
- if (bytes_to_append) {
+ while (keep_decoding) {
+ // Fill decoder_state->frame_buffer as much as possible.
+ int bytes_free_in_frame_buffer = SBC_MAX_FRAME_LEN - decoder_state->bytes_in_frame_buffer;
+ int bytes_to_append = btstack_min(input_bytes_to_process, bytes_free_in_frame_buffer);
+ if (bytes_to_append){
append_received_sbc_data(decoder_state, buffer, bytes_to_append);
buffer += bytes_to_append;
input_bytes_to_process -= bytes_to_append;
}
- uint16_t bytes_in_buffer_before = decoder_state->bytes_in_frame_buffer;
- uint16_t bytes_processed = 0;
+ // Decode the next frame in decoder_state->frame_buffer.
+ int bytes_in_frame_buffer_before_decoding = decoder_state->bytes_in_frame_buffer;
const OI_BYTE *frame_data = decoder_state->frame_buffer;
-
- static int frame_count = 0;
- while (1){
- if (corrupt_frame_period > 0){
- frame_count++;
-
- if (frame_count % corrupt_frame_period == 0){
- *(uint8_t*)&frame_data[5] = 0;
- frame_count = 0;
- }
- }
-
- OI_STATUS status = OI_STATUS_SUCCESS;
- int bad_frame = 0;
- int zero_seq_found = 0;
-
- if (decoder_state->first_good_frame_found){
- zero_seq_found = find_sequence_of_zeros(frame_data, decoder_state->bytes_in_frame_buffer, 20);
- bad_frame = zero_seq_found || packet_status_flag;
- }
-
- if (bad_frame){
- status = OI_CODEC_SBC_CHECKSUM_MISMATCH;
- decoder_state->bytes_in_frame_buffer = 0;
- } else {
- memset(decoder_state->pcm_plc_data, 0x55, SBC_MAX_CHANNELS * SBC_MAX_BANDS * SBC_MAX_BLOCKS * 2);
- status = OI_CODEC_SBC_DecodeFrame(&(decoder_state->decoder_context),
+ OI_UINT32 frame_data_len = decoder_state->bytes_in_frame_buffer;
+ OI_STATUS status = OI_CODEC_SBC_DecodeFrame(&(decoder_state->decoder_context),
&frame_data,
- &(decoder_state->bytes_in_frame_buffer),
+ &frame_data_len,
decoder_state->pcm_plc_data,
&(decoder_state->pcm_bytes));
- }
-
- bytes_processed = bytes_in_buffer_before - decoder_state->bytes_in_frame_buffer;
- switch(status){
- case OI_STATUS_SUCCESS:
- decoder_state->first_good_frame_found = 1;
-
- if (state->mode == SBC_MODE_mSBC){
- decoder_state->search_new_sync_word = 1;
- decoder_state->sync_word_found = 0;
- }
-
- state->handle_pcm_data(decoder_state->pcm_plc_data,
- btstack_sbc_decoder_num_samples_per_frame(state),
- btstack_sbc_decoder_num_channels(state),
- btstack_sbc_decoder_sample_rate(state), state->context);
- state->good_frames_nr++;
- continue;
- case OI_CODEC_SBC_NOT_ENOUGH_HEADER_DATA:
- case OI_CODEC_SBC_NOT_ENOUGH_BODY_DATA:
- // printf(" NOT_ENOUGH_DATA\n");
- if (decoder_state->sync_word_found){
- decoder_state->search_new_sync_word = 0;
- }
- break;
- case OI_CODEC_SBC_NO_SYNCWORD:
- case OI_CODEC_SBC_CHECKSUM_MISMATCH:
- // printf("NO_SYNCWORD or CHECKSUM_MISMATCH\n");
- decoder_state->bytes_in_frame_buffer = 0;
- if (!decoder_state->first_good_frame_found) break;
-
- if (zero_seq_found){
- state->zero_frames_nr++;
- } else {
- state->bad_frames_nr++;
- }
- if (!plc_enabled) break;
- break;
- default:
- log_info("Frame decode error: %d", status);
- break;
- }
-
- memmove(decoder_state->frame_buffer, decoder_state->frame_buffer + bytes_processed, decoder_state->bytes_in_frame_buffer);
- if ((status != OI_STATUS_SUCCESS) || (decoder_state->bytes_in_frame_buffer == 0)) break;
+ uint16_t bytes_processed = bytes_in_frame_buffer_before_decoding - frame_data_len;
+
+ static int frame_count = 0;
+ if (corrupt_frame_period > 0){
+ frame_count++;
+ if (frame_count % corrupt_frame_period == 0){
+ *(uint8_t*)&frame_data[5] = 0;
+ frame_count = 0;
+ }
}
+
+ // Handle decoding result.
+ switch(status){
+ case OI_STATUS_SUCCESS:
+ case OI_CODEC_SBC_PARTIAL_DECODE:
+ if (state->mode == SBC_MODE_mSBC){
+ decoder_state->search_new_sync_word = 1;
+ decoder_state->sync_word_found = 0;
+ }
+
+ state->handle_pcm_data(decoder_state->pcm_plc_data,
+ btstack_sbc_decoder_num_samples_per_frame(state),
+ btstack_sbc_decoder_num_channels(state),
+ btstack_sbc_decoder_sample_rate(state), state->context);
+ state->good_frames_nr++;
+ break;
+
+ case OI_CODEC_SBC_NOT_ENOUGH_HEADER_DATA:
+ case OI_CODEC_SBC_NOT_ENOUGH_BODY_DATA:
+ case OI_CODEC_SBC_NOT_ENOUGH_AUDIO_DATA:
+ if (decoder_state->sync_word_found){
+ decoder_state->search_new_sync_word = 0;
+ }
+ if (input_bytes_to_process > 0){
+ // Should never occur: The SBC code claims there is not enough bytes in the frame_buffer,
+ // but the frame_buffer was full. (The frame_buffer is always full before decoding when input_bytes_to_process > 0.)
+ // Clear frame_buffer.
+ log_info("SBC decode: frame_buffer too small for frame");
+ bytes_processed = bytes_in_frame_buffer_before_decoding;
+ } else {
+ // Exit decode loop, because there is not enough data in frame_buffer to decode the next frame.
+ keep_decoding = 0;
+ }
+ break;
+
+ case OI_CODEC_SBC_NO_SYNCWORD:
+ // This means the entire frame_buffer did not contain the syncword.
+ // Discard the frame_buffer contents.
+ log_info("SBC decode: no syncword found");
+ bytes_processed = bytes_in_frame_buffer_before_decoding;
+ break;
+
+ case OI_CODEC_SBC_CHECKSUM_MISMATCH:
+ // The next frame is somehow corrupt.
+ log_info("SBC decode: checksum error");
+ // Did the codec consume any bytes?
+ if (bytes_processed > 0){
+ // Good. Nothing to do.
+ } else {
+ // Skip the bogus frame by skipping the header.
+ bytes_processed = 1;
+ }
+ break;
+
+ case OI_STATUS_INVALID_PARAMETERS:
+ // This caused by corrupt frames.
+ // The codec apparently does not recover from this.
+ // Re-initialize the codec.
+ log_info("SBC decode: invalid parameters: resetting codec");
+ if (OI_CODEC_SBC_DecoderReset(&(bd_decoder_state.decoder_context), bd_decoder_state.decoder_data, sizeof(bd_decoder_state.decoder_data), 2, 2, FALSE) != OI_STATUS_SUCCESS){
+ log_info("SBC decode: resetting codec failed");
+
+ }
+ break;
+ default:
+ // Anything else went wrong.
+ // Skip a few bytes and try again.
+ bytes_processed = 1;
+ log_info("SBC decode: unknown status %d", status);
+ break;
+ }
+
+ // Remove decoded frame from decoder_state->frame_buffer.
+ if (bytes_processed > bytes_in_frame_buffer_before_decoding) {
+ bytes_processed = bytes_in_frame_buffer_before_decoding;
+ }
+ memmove(decoder_state->frame_buffer, decoder_state->frame_buffer + bytes_processed, bytes_in_frame_buffer_before_decoding - bytes_processed);
+ decoder_state->bytes_in_frame_buffer -= bytes_processed;
}
}
@@ -337,7 +354,7 @@ static void btstack_sbc_decoder_process_msbc_data(btstack_sbc_decoder_state_t *
break;
}
- uint16_t bytes_in_buffer_before = decoder_state->bytes_in_frame_buffer;
+ uint16_t bytes_in_frame_buffer_before_decoding = decoder_state->bytes_in_frame_buffer;
uint16_t bytes_processed = 0;
const OI_BYTE *frame_data = decoder_state->frame_buffer;
@@ -379,7 +396,7 @@ static void btstack_sbc_decoder_process_msbc_data(btstack_sbc_decoder_state_t *
&(decoder_state->pcm_bytes));
}
- bytes_processed = bytes_in_buffer_before - decoder_state->bytes_in_frame_buffer;
+ bytes_processed = bytes_in_frame_buffer_before_decoding - decoder_state->bytes_in_frame_buffer;
OI_UINT32 bytes_in_frame_buffer = msbc_frame_size;
switch(status){