[FFmpeg-devel] [PATCH 2/7] avutil: add av_jni_{get, set}_android_app_ctx helper

[Andreas Rheinhardt]

Matthieu Bouron:
> This will allow users to pass the Android ApplicationContext which is mandatory
> to retrieve the ContentResolver responsible to resolve/open Android content-uri.
> ---
>  libavutil/jni.c | 28 ++++++++++++++++++++++++++++
>  libavutil/jni.h | 17 +++++++++++++++++
>  2 files changed, 45 insertions(+)
> 
> diff --git a/libavutil/jni.c b/libavutil/jni.c
> index 541747cb20..d6f96717b0 100644
> --- a/libavutil/jni.c
> +++ b/libavutil/jni.c
> @@ -34,6 +34,7 @@
>  #include "libavutil/jni.h"
>  
>  static void *java_vm;
> +static void *android_app_ctx;
>  static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
>  
>  int av_jni_set_jvm(void *vm, void *log_ctx)
> @@ -63,6 +64,24 @@ void *av_jni_get_jvm(void *log_ctx)
>      return vm;
>  }
>  
> +void av_jni_set_android_app_ctx(void *app_ctx)
> +{
> +    pthread_mutex_lock(&lock);
> +    android_app_ctx = app_ctx;
> +    pthread_mutex_unlock(&lock);
> +}
> +
> +void *av_jni_get_android_app_ctx(void)
> +{
> +    void *ctx;
> +
> +    pthread_mutex_lock(&lock);
> +    ctx = android_app_ctx;
> +    pthread_mutex_unlock(&lock);
> +
> +    return ctx;
> +}
> +
>  #else
>  
>  int av_jni_set_java_vm(void *vm, void *log_ctx)
> @@ -75,4 +94,13 @@ void *av_jni_get_java_vm(void *log_ctx)
>      return NULL;
>  }
>  
> +void av_jni_set_android_app_ctx(void *app_ctx)
> +{
> +}
> +
> +void *av_jni_get_android_app_ctx(void)
> +{
> +    return NULL;
> +}
> +
>  #endif
> diff --git a/libavutil/jni.h b/libavutil/jni.h
> index 700960dbb8..630f4074a1 100644
> --- a/libavutil/jni.h
> +++ b/libavutil/jni.h
> @@ -43,4 +43,21 @@ int av_jni_set_jvm(void *vm, void *log_ctx);
>   */
>  void *av_jni_get_jvm(void *log_ctx);
>  
> +/*
> + * Set the Android application context which will be used to retrieve the Android
> + * content resolver to resolve content uris.
> + *
> + * @param app_ctx global JNI reference to the Android application context
> + */
> +void av_jni_set_android_app_ctx(void *app_ctx);
> +
> +/*
> + * Get the Android application context that has been set with
> + * av_jni_set_android_app_ctx.
> + *
> + * @return a pointer the the Android application context
> + */
> +void *av_jni_get_android_app_ctx(void);
> +
> +
>  #endif /* AVUTIL_JNI_H */

This adds global state in order to pass the application context to your
protocol (in lieu of an option to pass pointers to a protocol). Can
there be scenarios in which multiple application contexts are useful in
the same process?

- Andreas