On Fri, 1 Dec 2023 15:00:50 GMT, Alexander Zvegintsev <azveg...@openjdk.org>
wrote:
>> @azvegint do you think it would make sense to do it in the native code or in
>> the upper level Java code ? AND also how many times do you think it would
>> make sense to retry provided this could be a permanent pipewire error and so
>> it wont be sitting there re-trying with the same error forever ? (EDIT): i
>> see you have mentioned in the bug just 1 retry. i think it would still make
>> sense to do something about the case where even the 2nd attempt does not
>> succeed ie notify the caller somehow (retval/exception) that it has failed.
>
> I think it's better to do it in the native, to avoid extra native-java hops.
>
> As for the number of extra attempts, I think one-two is enough.
>
> Something like this (I haven't tested it thoroughly yet):
>
>
> diff --git
> a/src/java.desktop/unix/native/libawt_xawt/awt/screencast_pipewire.c
> b/src/java.desktop/unix/native/libawt_xawt/awt/screencast_pipewire.c
> index 6a7c4124935..a7c5aadb1ae 100644
> --- a/src/java.desktop/unix/native/libawt_xawt/awt/screencast_pipewire.c
> +++ b/src/java.desktop/unix/native/libawt_xawt/awt/screencast_pipewire.c
> @@ -855,6 +855,32 @@ static void arrayToRectangles(JNIEnv *env,
> (*env)->ReleaseIntArrayElements(env, boundsArray, body, 0);
> }
>
> +static int makeAnAttempt(
> + const gchar *token,
> + GdkRectangle *requestedArea,
> + GdkRectangle *affectedScreenBounds,
> + gint affectedBoundsLength) {
> + if (!initScreencast(token, affectedScreenBounds, affectedBoundsLength)) {
> + return pw.pwFd;
> + }
> +
> + if (!doLoop(*requestedArea)) {
> + return RESULT_ERROR;
> + }
> +
> + while (!isAllDataReady()) {
> + fp_pw_thread_loop_lock(pw.loop);
> + fp_pw_thread_loop_wait(pw.loop);
> + if (hasPipewireFailed) {
> + fp_pw_thread_loop_unlock(pw.loop);
> + doCleanup();
> + return RESULT_ERROR;
> + }
> + fp_pw_thread_loop_unlock(pw.loop);
> + }
> + return RESULT_OK;
> +}
> +
> /*
> * Class: sun_awt_screencast_ScreencastHelper
> * Method: closeSession
> @@ -911,25 +937,17 @@ JNIEXPORT jint JNICALL
> Java_sun_awt_screencast_ScreencastHelper_getRGBPixelsImpl
> jx, jy, jwidth, jheight, token
> );
>
> - if (!initScreencast(token, affectedScreenBounds, affectedBoundsLength)) {
> - releaseToken(env, jtoken, token);
> - return pw.pwFd;
> - }
> -
> - if (!doLoop(requestedArea)) {
> - releaseToken(env, jtoken, token);
> - return RESULT_ERROR;
> - }
> + int attemptResult = makeAnAttempt(token, &requestedArea,
> + affectedScreenBounds,
> affectedBoundsLength);
>
> - while (!isAllDataReady()) {
> - fp_pw_thread_loop_lock(pw.loop);
> - fp_pw_thread_loop_wait(pw.loop);
> - if (hasPipewireFailed) {
> - fp_pw_thread_loop_unlock(pw.loop);
> + if (attemptResult) {
> + DEBUG_SCREENCAST("First attempt failed with %i, re-trying...\n",
> attemptResult);
> + attemptResult = makeAnAttempt(token, &requestedArea,
> + affectedScreenBounds,
> affectedBoundsLengt...
@azvegint let me have a look next week and i'll try to come up with another PR
for this. the pipewire is a bit tricky to test in my experience as there are
quite a few moving parts/layers there and on some error conditions it even
hangs bc they chose to use no timeouts in their implementation so it just gets
stuck there forever sometimes, so i would need to come up with some way/s to
test this.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/16794#discussion_r1412359619
