Use signal-safe functions in signal handler #3557
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mkindahl
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Reporting errors using `ereport` can call `malloc()`, which is not signal-safe. Using `ereport()` in a signal handler can therefore cause `malloc()` to run nested inside `malloc()` if the termination handler is called in the middle of a `malloc()` call, which will trigger an assertion in `malloc()` that will take down the server. This commit fixes this by using the signal-safe `write_stderr()` inside the signal handlers for the background workers. Fixes timescale#3469
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Reporting errors using
ereportcan callmalloc(), which is notsignal-safe. Using
ereport()in a signal handler can therefore causemalloc()to run nested insidemalloc()if the termination handleris called in the middle of a
malloc()call, which will trigger anassertion in
malloc()that will take down the server.This commit fixes this by using the signal-safe
write_stderr()insidethe signal handlers for the background workers.
Fixes #3469