Use dumpsys deviceidle get screen in CMD_SCREEN_ON - #369
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This PR: - fixes a broken pipe like in JeffLIrion#351, but from `grep -q` instead of `grep -m 1` - uses a much more efficient call to get screen state On Android 14, both `dumpsys power` greps no longer match. It prints `Display Power: com.android.server.power.PowerManagerService$1@a8a75e6` with no `state=` field, and `mScreenOn=true` is gone. So each poll, every 10 seconds, falls back to `dumpsys display`, a much more expensive call. Because `grep -q` terminates on first match, the pipe is broken, resulting in a stack trace every 10 seconds that looks like: ``` W FastPrintWriter: Write failure W FastPrintWriter: java.io.IOException: write failed: EPIPE (Broken pipe) W FastPrintWriter: at libcore.io.IoBridge.write(IoBridge.java:651) W FastPrintWriter: at java.io.FileOutputStream.write(FileOutputStream.java:432) W FastPrintWriter: at com.android.internal.util.FastPrintWriter.flushBytesLocked(FastPrintWriter.java:355) W FastPrintWriter: at com.android.internal.util.FastPrintWriter.flushLocked(FastPrintWriter.java:378) W FastPrintWriter: at com.android.internal.util.FastPrintWriter.flush(FastPrintWriter.java:413) W FastPrintWriter: at android.os.Binder.dump(Binder.java:1158) W FastPrintWriter: at android.os.Binder.onTransact(Binder.java:1022) W FastPrintWriter: Caused by: android.system.ErrnoException: write failed: EPIPE (Broken pipe) W FastPrintWriter: at libcore.io.IoBridge.write(IoBridge.java:646) W FastPrintWriter: ... 9 more ``` This PR fixes the issue: - uses `dumpsys deviceidle get screen` to check screen state, which is cheap and has been available since Android 7 - removes `-q` so grep will not stop on first match and cause broken pipe
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This PR:
grep -qinstead ofgrep -m 1On Android 14, both
dumpsys powergreps no longer match. It printsDisplay Power: com.android.server.power.PowerManagerService$1@a8a75e6with nostate=field, andmScreenOn=trueis gone. So each poll, every 10 seconds, falls back todumpsys display, a much more expensive call.EDIT: Tested on LineageOS 21 (Android 14, SDK 34), x86_64 Android TV.
Because
grep -qterminates on first match, the pipe is broken, resulting in a stack trace every 10 seconds that looks like:This PR fixes the issue:
dumpsys deviceidle get screento check screen state, which is cheap and has been available since Android 7-qso grep will not stop on first match and cause broken pipe> /dev/nullis now needed to replace output suppression that-qprovided