The current runtime attempts to forward signals generated by non-Go
code to the original signal handler. If it can't call the original
handler directly, it currently attempts to re-raise the signal after
resetting the handler. In this case, the original context is lost.
This fix prevents that problem by simply returning from the go signal
handler after resetting the original handler. It only does this when
the original handler is the system default handler, which in all cases
is known to not recover. The signal is not reset, so it is retriggered
and the original handler takes over with the proper context.
Fixes#14899
Change-Id: Ib1c19dfa4b50d9732d7a453de3784c8141e1cbb3
Reviewed-on: https://go-review.googlesource.com/21006
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Use the current ability to say that we don't do anything with SIGCONT by
default, but programs can catch it using signal.Notify if they want.
Fixes#8953.
Change-Id: I67d40ce36a029cbc58a235cbe957335f4a58e1c5
Reviewed-on: https://go-review.googlesource.com/18185
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
If non-Go code calls sigaltstack before a signal is received, use
sigaltstack to determine the current signal stack and set the gsignal
stack to use it. This makes the Go runtime more robust in the face of
non-Go code. We still can't handle a disabled signal stack or a signal
triggered with SA_ONSTACK clear, but we now give clear errors for those
cases.
Fixes#7227.
Update #9896.
Change-Id: Icb1607e01fd6461019b6d77d940e59b3aed4d258
Reviewed-on: https://go-review.googlesource.com/18102
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Mikio Hara <mikioh.mikioh@gmail.com>