This is a placeholder for future options (e.g. JSON).
The parameter is temporarily variadic to avoid breaking
x/telemetry (see CL 585378), but I plan to remove
the "..." later this week.
Updates #67182
Change-Id: I3f6f39455d852f92902f8e3f007d3093cbe555db
Reviewed-on: https://go-review.googlesource.com/c/go/+/585557
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Austin Clements <austin@google.com>
There are two separate cases here:
The base case is simple: a concurrent call to SetCrashOutput while
panicking will switch the crash FD, which could cause the first half of
writes to go to the old FD, and the second half to the new FD. This
isn't a correctness problem, but would be annoying to see in practice.
Since it is easy to check for, I simply drop any changes if panicking is
already in progress.
The second case is more important: SetCrashOutput will close the old FD
after the new FD is swapped, but writeErrData has no locking around use
of the fd, so SetCrashOutput could close the FD out from under
writeErrData, causing lost writes. We handle this similarly, by not
allowing SetCrashOutput to close the old FD if a panic is in progress,
but we have to be more careful about synchronization between
writeErrData and setCrashFD to ensure that writeErrData can't observe
the old FD while setCrashFD allows close.
For #42888.
Change-Id: I7270b2cc5ea58a15ba40145b7a96d557acdfe842
Reviewed-on: https://go-review.googlesource.com/c/go/+/559801
Reviewed-by: Alan Donovan <adonovan@google.com>
Auto-Submit: Michael Pratt <mpratt@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
SetCrashOutput dup's the input file for safety, but I don't think that
the docs are very clear about what the caller can/should do with f. "it
does not close the previous file" is particularly confusing, as it does
close the previous FD (but not the previous passed os.File).
Expand and attempt to clarify the explanation, borrowing wording from
net.FileConn, which also dup's the input os.File.
For #42888.
Change-Id: I1c96d2dce7899e335d8f1cd464d2d9b31aeb4e5e
Reviewed-on: https://go-review.googlesource.com/c/go/+/559800
Reviewed-by: Alan Donovan <adonovan@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
This feature makes it possible to record unhandled panics
in any goroutine through a watchdog process (e.g. the same
application forked+exec'd as a child in a special mode)
that can process the panic report, for example by sending
it to a crash-reporting system such as Go telemetry
or Sentry.
Fixes#42888
Change-Id: I5aa7be8f726bbc70fc650540bd1a14ab60c62ecb
Reviewed-on: https://go-review.googlesource.com/c/go/+/547978
Reviewed-by: Michael Pratt <mpratt@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Alan Donovan <adonovan@google.com>
Reviewed-by: Russ Cox <rsc@golang.org>
