Prevent dangling cat-file calls (goroutine alternative) (#19454) #19466
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If an `os/exec.Command` is passed non `*os.File` as an input/output, go will create `os.Pipe`s and wait for their closure in `cmd.Wait()`. If the code following this is responsible for closing `io.Pipe`s or other handlers then on process death from context cancellation the `Wait` can hang. There are two possible solutions: 1. use `os.Pipe` as the input/output as `cmd.Wait` does not wait for these. 2. create a goroutine waiting on the context cancellation that will close the inputs. This PR provides the second option - which is a simpler change that can be more easily backported. Closes go-gitea#19448 Signed-off-by: Andrew Thornton <art27@cantab.net>
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Backport #19454
If an
os/exec.Commandis passed non*os.Fileas an input/output, gowill create
os.Pipes and wait for their closure incmd.Wait(). Ifthe code following this is responsible for closing
io.Pipes or otherhandlers then on process death from context cancellation the
Waitcanhang.
There are two possible solutions:
os.Pipeas the input/output ascmd.Waitdoes not wait for these.This PR provides the second option - which is a simpler change that can
be more easily backported.
Signed-off-by: Andrew Thornton art27@cantab.net