[pulseaudio-discuss] [PATCH] padsp: Write non-frame-aligned chunks to the stream

[Tanu Kaskinen]

On Wed, 2017-05-31 at 15:18 +0900, Arun Raghavan wrote:
> Subject: [PATCH] padsp: Write non-frame-aligned chunks to the stream

To me the patch title sounds the opposite of what the patch does.

> ---
>  src/utils/padsp.c | 20 +++++++++++++++-----
>  1 file changed, 15 insertions(+), 5 deletions(-)
> 
> diff --git a/src/utils/padsp.c b/src/utils/padsp.c
> index f74122a..fb3dbed 100644
> --- a/src/utils/padsp.c
> +++ b/src/utils/padsp.c
> @@ -52,6 +52,7 @@
>  #include <pulse/gccmacro.h>
>  #include <pulsecore/llist.h>
>  #include <pulsecore/core-util.h>
> +#include <pulsecore/sample-util.h>
>  
>  /* On some systems SIOCINQ isn't defined, but FIONREAD is just an alias */
>  #if !defined(SIOCINQ) && defined(FIONREAD)
> @@ -92,6 +93,7 @@ struct fd_info {
>      pa_io_event_flags_t io_flags;
>  
>      void *buf;
> +    size_t leftover;
>      size_t rec_offset;
>  
>      int operation_success;
> @@ -641,6 +643,7 @@ static fd_info* fd_info_new(fd_info_type_t type, int *_errno) {
>      pthread_mutex_init(&i->mutex, NULL);
>      i->ref = 1;
>      i->buf = NULL;
> +    i->leftover = 0;
>      i->rec_offset = 0;
>      i->unusable = 0;
>      pa_cvolume_reset(&i->sink_volume, 2);
> @@ -866,15 +869,18 @@ static int fd_info_copy_data(fd_info *i, int force) {
>  
>          while (n >= i->fragment_size || force) {
>              ssize_t r;
> +            size_t to_write;
>  
>              if (!i->buf) {
>                  if (!(i->buf = malloc(i->fragment_size))) {
>                      debug(DEBUG_LEVEL_NORMAL, __FILE__": malloc() failed.\n");
>                      return -1;
>                  }
> +
> +                i->leftover = 0;
>              }
>  
> -            if ((r = read(i->thread_fd, i->buf, i->fragment_size)) <= 0) {
> +            if ((r = read(i->thread_fd, ((uint8_t *) i->buf) + i->leftover, i->fragment_size - i->leftover)) <= 0) {
>  
>                  if (errno == EAGAIN)
>                      break;
> @@ -883,15 +889,19 @@ static int fd_info_copy_data(fd_info *i, int force) {
>                  return -1;
>              }
>  
> -            if (pa_stream_write(i->play_stream, i->buf, (size_t) r, free, 0LL, PA_SEEK_RELATIVE) < 0) {
> +            to_write = pa_frame_align(r + i->leftover, &i->sample_spec);
> +
> +            if (pa_stream_write(i->play_stream, i->buf, to_write, NULL, 0LL, PA_SEEK_RELATIVE) < 0) {
>                  debug(DEBUG_LEVEL_NORMAL, __FILE__": pa_stream_write(): %s\n", pa_strerror(pa_context_errno(i->context)));
>                  return -1;
>              }
>  
> -            i->buf = NULL;
> +            i->leftover = r - to_write;

As the bug reporter said, this doesn't work correctly.

I think the code would be bit easier to follow if you added another
variable for holding the amount of bytes in i->buf. This line would
then become

    i->leftover = nbytes_in_buf - to_write;

-- 
Tanu

https://www.patreon.com/tanuk