[FFmpeg-devel] [PATCHv2] avutil/thread: Add pthread_cond_timedwait function

[Matt Oliver]

On Mon, 20 Jan 2020 at 11:14, Marton Balint <cus at passwd.hu> wrote:

> From: Matt Oliver <protogonoi at gmail.com>
>
> v2: fix calculating milisecond times and use SleepConditionVariableSRW.
>
> Signed-off-by: Matt Oliver <protogonoi at gmail.com>
> ---
>  compat/os2threads.h  | 25 +++++++++++++++++++++++++
>  compat/w32pthreads.h | 18 ++++++++++++++++++
>  libavutil/thread.h   |  7 +++++++
>  3 files changed, 50 insertions(+)
>
> diff --git a/compat/os2threads.h b/compat/os2threads.h
> index 2177a033ec..eec6f40ae7 100644
> --- a/compat/os2threads.h
> +++ b/compat/os2threads.h
> @@ -31,11 +31,14 @@
>
>  #undef __STRICT_ANSI__          /* for _beginthread() */
>  #include <stdlib.h>
> +#include <time.h>
>
>  #include <sys/builtin.h>
>  #include <sys/fmutex.h>
>
>  #include "libavutil/attributes.h"
> +#include "libavutil/common.h"
> +#include "libavutil/time.h"
>
>  typedef struct {
>      TID tid;
> @@ -163,6 +166,28 @@ static av_always_inline int
> pthread_cond_broadcast(pthread_cond_t *cond)
>      return 0;
>  }
>
> +static av_always_inline int pthread_cond_timedwait(pthread_cond_t *cond,
> +                                                   pthread_mutex_t *mutex,
> +                                                   const struct timespec
> *abstime)
> +{
> +    int64_t abs_milli = abstime->tv_sec * 1000LL + abstime->tv_nsec /
> 1000000;
> +    ULONG t = av_clip64(abs_milli - av_gettime() / 1000, 0, ULONG_MAX);
> +
> +    __atomic_increment(&cond->wait_count);
> +
> +    pthread_mutex_unlock(mutex);
> +
> +    APIRET ret = DosWaitEventSem(cond->event_sem, t);
> +
> +    __atomic_decrement(&cond->wait_count);
> +
> +    DosPostEventSem(cond->ack_sem);
> +
> +    pthread_mutex_lock(mutex);
> +
> +    return (ret == ERROR_TIMEOUT) ? ETIMEDOUT : 0;
> +}
> +
>  static av_always_inline int pthread_cond_wait(pthread_cond_t *cond,
>                                                pthread_mutex_t *mutex)
>  {
> diff --git a/compat/w32pthreads.h b/compat/w32pthreads.h
> index 21acfd2ba1..7df33b7da4 100644
> --- a/compat/w32pthreads.h
> +++ b/compat/w32pthreads.h
> @@ -38,11 +38,13 @@
>  #define WIN32_LEAN_AND_MEAN
>  #include <windows.h>
>  #include <process.h>
> +#include <time.h>
>
>  #include "libavutil/attributes.h"
>  #include "libavutil/common.h"
>  #include "libavutil/internal.h"
>  #include "libavutil/mem.h"
> +#include "libavutil/time.h"
>
>  typedef struct pthread_t {
>      void *handle;
> @@ -156,6 +158,22 @@ static inline int pthread_cond_wait(pthread_cond_t
> *cond, pthread_mutex_t *mutex
>      return 0;
>  }
>
> +static inline int pthread_cond_timedwait(pthread_cond_t *cond,
> pthread_mutex_t *mutex,
> +                                         const struct timespec *abstime)
> +{
> +    int64_t abs_milli = abstime->tv_sec * 1000LL + abstime->tv_nsec /
> 1000000;
> +    DWORD t = av_clip64(abs_milli - av_gettime() / 1000, 0, UINT32_MAX);
> +
> +    if (!SleepConditionVariableSRW(cond, mutex, t, 0)) {
> +        DWORD err = GetLastError();
> +        if (err == ERROR_TIMEOUT)
> +            return ETIMEDOUT;
> +        else
> +            return EINVAL;
> +    }
> +    return 0;
> +}
> +
>  static inline int pthread_cond_signal(pthread_cond_t *cond)
>  {
>      WakeConditionVariable(cond);
> diff --git a/libavutil/thread.h b/libavutil/thread.h
> index cc5272d379..65b97ef303 100644
> --- a/libavutil/thread.h
> +++ b/libavutil/thread.h
> @@ -109,6 +109,12 @@ static inline int
> strict_pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t
>      ASSERT_PTHREAD(pthread_cond_wait, cond, mutex);
>  }
>
> +static inline int strict_pthread_cond_timedwait(pthread_cond_t *cond,
> pthread_mutex_t *mutex,
> +                                                const struct timespec
> *abstime)
> +{
> +    ASSERT_PTHREAD(pthread_cond_timedwait, cond, mutex, abstime);
> +}
> +
>  static inline int strict_pthread_once(pthread_once_t *once_control, void
> (*init_routine)(void))
>  {
>      ASSERT_PTHREAD(pthread_once, once_control, init_routine);
> @@ -124,6 +130,7 @@ static inline int strict_pthread_once(pthread_once_t
> *once_control, void (*init_
>  #define pthread_cond_signal    strict_pthread_cond_signal
>  #define pthread_cond_broadcast strict_pthread_cond_broadcast
>  #define pthread_cond_wait      strict_pthread_cond_wait
> +#define pthread_cond_timedwait strict_pthread_cond_timedwait
>  #define pthread_once           strict_pthread_once
>  #endif
>
> --
> 2.16.4
>
>
lgtm