Prevent StateFailed after SIGKILL

[mostlygeek]

Improves #125 so after force termination, the process can be restarted. Supersedes #128 with a much simpler fix.

Summary by CodeRabbit

• Bug Fixes
  • Resolved a race condition related to process termination, ensuring more reliable handling when a process is killed.

[coderabbitai]

Walkthrough

A conditional check was added in the goroutine inside the start() method of the Process struct to suppress sending an exit error to the p.cmdWaitChan channel if the error string is exactly "signal: killed". This change addresses a race condition when handling process termination via SIGKILL.

Changes

File(s)	Change Summary
proxy/process.go	Added a check to prevent sending "signal: killed" errors to p.cmdWaitChan in a goroutine.

Sequence Diagram(s)

sequenceDiagram
    participant Process
    participant Goroutine
    participant UpstreamCmd

    Process->>Goroutine: Start goroutine to wait for UpstreamCmd exit
    Goroutine->>UpstreamCmd: Wait for exit (cmd.Wait())
    UpstreamCmd-->>Goroutine: Return error (could be "signal: killed")
    alt error is "signal: killed"
        Goroutine-->>Goroutine: Suppress sending error to p.cmdWaitChan
    else other errors
        Goroutine->>Process: Send error to p.cmdWaitChan
    end

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📜 Recent review details

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Review profile: CHILL
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📥 Commits

Reviewing files that changed from the base of the PR and between 7f37bcc and 93c0c20.

📒 Files selected for processing (1)

• proxy/process.go (1 hunks)

🔇 Additional comments (1)

proxy/process.go (1)

217-222: Good fix for the race condition during SIGKILL handling.

This change elegantly prevents a race condition when a process is terminated with SIGKILL. By suppressing the "signal: killed" error from being sent to the cmdWaitChan, the process won't incorrectly transition to StateFailed when it's intentionally killed.

✨ Finishing Touches

• 📝 Generate Docstrings

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