[pulseaudio-discuss] [PATCH v11 03/11] bluetooth: Implement reading SO_TIMESTAMP for A2DP source

[Tanu Kaskinen]

On Sun, 2019-06-02 at 17:25 +0200, Pali Rohár wrote:
> ---
>  src/modules/bluetooth/module-bluez5-device.c | 31 ++++++++++++++++++++++++++--
>  1 file changed, 29 insertions(+), 2 deletions(-)
> 
> diff --git a/src/modules/bluetooth/module-bluez5-device.c b/src/modules/bluetooth/module-bluez5-device.c
> index c0b293d94..e79d472bc 100644
> --- a/src/modules/bluetooth/module-bluez5-device.c
> +++ b/src/modules/bluetooth/module-bluez5-device.c
> @@ -536,6 +536,10 @@ static int a2dp_process_push(struct userdata *u) {
>      memchunk.index = memchunk.length = 0;
>  
>      for (;;) {
> +        uint8_t aux[1024];
> +        struct iovec iov;
> +        struct cmsghdr *cm;
> +        struct msghdr m;
>          bool found_tstamp = false;
>          pa_usec_t tstamp;
>          uint8_t *ptr;
> @@ -544,7 +548,19 @@ static int a2dp_process_push(struct userdata *u) {
>  
>          a2dp_prepare_decoder_buffer(u);
>  
> -        l = pa_read(u->stream_fd, u->decoder_buffer, u->read_encoded_block_size, &u->stream_write_type);
> +        pa_zero(m);
> +        pa_zero(aux);
> +        pa_zero(iov);
> +
> +        m.msg_iov = &iov;
> +        m.msg_iovlen = 1;
> +        m.msg_control = aux;
> +        m.msg_controllen = sizeof(aux);
> +
> +        iov.iov_base = u->decoder_buffer;
> +        iov.iov_len = u->read_encoded_block_size;
> +
> +        l = recvmsg(u->stream_fd, &m, 0);
>  
>          if (l <= 0) {
>  
> @@ -564,8 +580,19 @@ static int a2dp_process_push(struct userdata *u) {
>          pa_assert((size_t) l <= u->decoder_buffer_size);
>  
>          /* TODO: get timestamp from rtp */
> +
> +        for (cm = CMSG_FIRSTHDR(&m); cm; cm = CMSG_NXTHDR(&m, cm)) {
> +            if (cm->cmsg_level == SOL_SOCKET && cm->cmsg_type == SO_TIMESTAMP) {
> +                struct timeval *tv = (struct timeval*) CMSG_DATA(cm);
> +                pa_rtclock_from_wallclock(tv);
> +                tstamp = pa_timeval_load(tv);
> +                found_tstamp = true;
> +                break;
> +            }
> +        }
> +
>          if (!found_tstamp) {
> -            /* pa_log_warn("Couldn't find SO_TIMESTAMP data in auxiliary recvmsg() data!"); */
> +            pa_log_warn("Couldn't find SO_TIMESTAMP data in auxiliary recvmsg() data!");

If SO_TIMESTAMP isn't set on one message, it's probably not set on any
message. Flooding the log isn't good, so this needs some rework. Maybe
PA_ONCE_BEGIN/END would be appropriate here?

-- 
Tanu

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