Bionic libc clock_nanosleep() error mechanism does not corresponds to Linux/Posix [216495770]

Fixed

Bug

[AOSP] assigned

Status Update

No update yet.

Description

se...@gmail.com

created issue #1

Jan 27, 2022 01:02PM

Hi,

I've been experiencing crashes of an application related to the fact that clock_nanosleep() is returning -1.

11-30 14:26:53.087   176   176 I DEBUG   : signal 6 (SIGABRT), code -6 (SI_TKILL), fault addr --------
11-30 14:26:53.192   176   176 I DEBUG   : Abort message: 'monoeg_g_usleep: clock_nanosleep () returned -1'

From the clock_nanosleep() Linux/Posix implementation it is stated that: RETURN VALUE On successfully sleeping for the requested interval, clock_nanosleep() returns 0. If the call is interrupted by a signal handler or encoun‐ ters an error, then it returns one of the positive error number listed in ERRORS.

When looking at the code of Bionic libc I can see:

https://android.googlesource.com/platform/bionic/+/faa0fdb/libc/arch-arm/syscalls/clock_nanosleep.S

ENTRY(clock_nanosleep)
    mov     ip, r7
    ldr     r7, =__NR_clock_nanosleep
    swi     #0
    mov     r7, ip
    movs    r0, r0
    bxpl    lr
    b       __set_syscall_errno
END(clock_nanosleep)

=> clock_nanosleep() is using __set_syscall_errno has the error reporting mechanism https://android.googlesource.com/platform/bionic/+/ics-mr1-release/libc/bionic/__set_errno.c

We can see that clock_nanosleep implementation in Bionic libc will return -1 uppon error and set errno which is not the behavior expected from POSIX clock_nanosleep().

Don't hesitate if I'm wrong or you need more information.

Seb

Comments

vi...@google.com <vi...@google.com> #2Jan 28, 2022 06:29AM

Assigned to vi...@google.com.

Information redacted by Android Beta Feedback.

ei...@gmail.com <ei...@gmail.com> #3Jan 28, 2022 08:11AM

Comment has been deleted.

Message last modified on Jan 28, 2022 08:11AM

se...@gmail.com <se...@gmail.com> #4Jan 28, 2022 08:12AM

Could you please let me know if without Android Auto usage and not using com.njm.njmsafedrivego and com.august.bennu lessen battery drain?

vi...@google.com <vi...@google.com> #5Jan 31, 2022 06:01AM

Battery drain remain the same.

On Fri, Apr 4, 2025, 09:37 <buganizer-system@google.com> wrote:

- Show quoted text -

en...@google.com <en...@google.com> #6Jan 31, 2022 05:27PM

Marked as fixed, reassigned to en...@google.com.

Could you please capture a bug report and share it here?

en...@google.com <en...@google.com> #7Jan 31, 2022 05:28PM

Please provide the requested information to proceed further. Unfortunately the issue will be closed within 7 days if there is no further update.

se...@gmail.com <se...@gmail.com> #8Jan 31, 2022 05:56PM

Hi and thank you very much for investigating this. Looking at the old source code did not help. I checked the patch and it definitely fixes the issue ! Time to upgrade my Android version. Thanks again.