[PATCH 1/6] winealsa: Introduce a helper to retrieve the time.

[Andrew Eikum]

Signed-off-by: Andrew Eikum <aeikum at codeweavers.com>

On Fri, Mar 25, 2022 at 08:42:14AM +0000, Huw Davies wrote:
> The motivation is that this will need to be called from a
> non-Win32 thread and so shouldn't use the Win32 API.  An
> added benefit is that it will eliminate the 16ms jitter
> associated with GetTickCount().
> 
> Signed-off-by: Huw Davies <huw at codeweavers.com>
> ---
>  dlls/winealsa.drv/alsamidi.c | 21 +++++++++++++++++----
>  1 file changed, 17 insertions(+), 4 deletions(-)
> 
> diff --git a/dlls/winealsa.drv/alsamidi.c b/dlls/winealsa.drv/alsamidi.c
> index 30c46eee64d..1633268b533 100644
> --- a/dlls/winealsa.drv/alsamidi.c
> +++ b/dlls/winealsa.drv/alsamidi.c
> @@ -31,6 +31,7 @@
>  #include <stdarg.h>
>  #include <stdio.h>
>  #include <pthread.h>
> +#include <time.h>
>  #include <alsa/asoundlib.h>
>  
>  #include "ntstatus.h"
> @@ -104,6 +105,18 @@ static void in_buffer_unlock(void)
>      pthread_mutex_unlock(&in_buffer_mutex);
>  }
>  
> +static uint64_t get_time_msec(void)
> +{
> +    struct timespec now = {0, 0};
> +
> +#ifdef CLOCK_MONOTONIC_RAW
> +    if (!clock_gettime(CLOCK_MONOTONIC_RAW, &now))
> +        return (uint64_t)now.tv_sec * 1000 + now.tv_nsec / 1000000;
> +#endif
> +    clock_gettime(CLOCK_MONOTONIC, &now);
> +    return (uint64_t)now.tv_sec * 1000 + now.tv_nsec / 1000000;
> +}
> +
>  static void set_in_notify(struct notify_context *notify, struct midi_src *src, WORD dev_id, WORD msg,
>                            UINT_PTR param_1, UINT_PTR param_2)
>  {
> @@ -924,7 +937,7 @@ static UINT midi_out_reset(WORD dev_id)
>  
>  static void handle_sysex_event(struct midi_src *src, BYTE *data, UINT len)
>  {
> -    UINT pos = 0, copy_len, current_time = NtGetTickCount() - src->startTime;
> +    UINT pos = 0, copy_len, current_time = get_time_msec() - src->startTime;
>      struct notify_context notify;
>      MIDIHDR *hdr;
>  
> @@ -957,7 +970,7 @@ static void handle_sysex_event(struct midi_src *src, BYTE *data, UINT len)
>  
>  static void handle_regular_event(struct midi_src *src, snd_seq_event_t *ev)
>  {
> -    UINT data = 0, value, current_time = NtGetTickCount() - src->startTime;
> +    UINT data = 0, value, current_time = get_time_msec() - src->startTime;
>      struct notify_context notify;
>  
>      switch (ev->type)
> @@ -1127,7 +1140,7 @@ static UINT midi_in_start(WORD dev_id)
>      if (src->state == -1) return MIDIERR_NODEVICE;
>  
>      src->state = 1;
> -    src->startTime = NtGetTickCount();
> +    src->startTime = get_time_msec();
>      return MMSYSERR_NOERROR;
>  }
>  
> @@ -1147,7 +1160,7 @@ static UINT midi_in_stop(WORD dev_id)
>  
>  static DWORD midi_in_reset(WORD dev_id, struct notify_context *notify)
>  {
> -    UINT cur_time = NtGetTickCount();
> +    UINT cur_time = get_time_msec();
>      UINT err = MMSYSERR_NOERROR;
>      struct midi_src *src;
>      MIDIHDR *hdr;
> -- 
> 2.25.1
> 
>