Clarify the git command Stdin hanging problem (#26967)

This commit is contained in:
wxiaoguang 2023-09-08 21:20:38 +08:00 committed by GitHub
parent bafe1334c6
commit 4807f7be22
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 12 additions and 17 deletions

View file

@ -221,8 +221,18 @@ type RunOpts struct {
Dir string Dir string
Stdout, Stderr io.Writer Stdout, Stderr io.Writer
Stdin io.Reader
PipelineFunc func(context.Context, context.CancelFunc) error // Stdin is used for passing input to the command
// The caller must make sure the Stdin writer is closed properly to finish the Run function.
// Otherwise, the Run function may hang for long time or forever, especially when the Git's context deadline is not the same as the caller's.
// Some common mistakes:
// * `defer stdinWriter.Close()` then call `cmd.Run()`: the Run() would never return if the command is killed by timeout
// * `go { case <- parentContext.Done(): stdinWriter.Close() }` with `cmd.Run(DefaultTimeout)`: the command would have been killed by timeout but the Run doesn't return until stdinWriter.Close()
// * `go { if stdoutReader.Read() err != nil: stdinWriter.Close() }` with `cmd.Run()`: the stdoutReader may never return error if the command is killed by timeout
// In the future, ideally the git module itself should have full control of the stdin, to avoid such problems and make it easier to refactor to a better architecture.
Stdin io.Reader
PipelineFunc func(context.Context, context.CancelFunc) error
} }
func commonBaseEnvs() []string { func commonBaseEnvs() []string {

View file

@ -122,21 +122,6 @@ func Init() {
indexer := *globalIndexer.Load() indexer := *globalIndexer.Load()
for _, indexerData := range items { for _, indexerData := range items {
log.Trace("IndexerData Process Repo: %d", indexerData.RepoID) log.Trace("IndexerData Process Repo: %d", indexerData.RepoID)
// FIXME: it seems there is a bug in `CatFileBatch` or `nio.Pipe`, which will cause the process to hang forever in rare cases
/*
sync.(*Cond).Wait(cond.go:70)
github.com/djherbis/nio/v3.(*PipeReader).Read(sync.go:106)
bufio.(*Reader).fill(bufio.go:106)
bufio.(*Reader).ReadSlice(bufio.go:372)
bufio.(*Reader).collectFragments(bufio.go:447)
bufio.(*Reader).ReadString(bufio.go:494)
code.gitea.io/gitea/modules/git.ReadBatchLine(batch_reader.go:149)
code.gitea.io/gitea/modules/indexer/code.(*BleveIndexer).addUpdate(bleve.go:214)
code.gitea.io/gitea/modules/indexer/code.(*BleveIndexer).Index(bleve.go:296)
code.gitea.io/gitea/modules/indexer/code.(*wrappedIndexer).Index(wrapped.go:74)
code.gitea.io/gitea/modules/indexer/code.index(indexer.go:105)
*/
if err := index(ctx, indexer, indexerData.RepoID); err != nil { if err := index(ctx, indexer, indexerData.RepoID); err != nil {
unhandled = append(unhandled, indexerData) unhandled = append(unhandled, indexerData)
if !setting.IsInTesting { if !setting.IsInTesting {