func fg(ec *EvalCtx, pids ...int) {
if len(pids) == 0 {
throw(ErrArgs)
}
var thepgid int
for i, pid := range pids {
pgid, err := syscall.Getpgid(pid)
maybeThrow(err)
if i == 0 {
thepgid = pgid
} else if pgid != thepgid {
throw(ErrNotInSameGroup)
}
}
err := sys.Tcsetpgrp(0, thepgid)
maybeThrow(err)
errors := make([]Error, len(pids))
for i, pid := range pids {
err := syscall.Kill(pid, syscall.SIGCONT)
if err != nil {
errors[i] = Error{err}
}
}
for i, pid := range pids {
if errors[i] != OK {
continue
}
var ws syscall.WaitStatus
_, err = syscall.Wait4(pid, &ws, syscall.WUNTRACED, nil)
if err != nil {
errors[i] = Error{err}
} else {
// TODO find command name
errors[i] = Error{NewExternalCmdExit(fmt.Sprintf("(pid %d)", pid), ws, pid)}
}
}
throwCompositeError(errors)
}
// Eval sets up the Evaler and evaluates a chunk. The supplied name and text are
// used in diagnostic messages.
func (ev *Evaler) Eval(op Op, name, text string) error {
inCh := make(chan Value)
close(inCh)
outCh := make(chan Value, outChanSize)
outDone := make(chan struct{})
go func() {
for v := range outCh {
fmt.Printf("%s%s\n", outChanLeader, v.Repr(initIndent))
}
close(outDone)
}()
ports := []*Port{
{File: os.Stdin, Chan: inCh},
{File: os.Stdout, Chan: outCh},
{File: os.Stderr, Chan: BlackholeChan},
}
// signal.Ignore(syscall.SIGTTIN)
// signal.Ignore(syscall.SIGTTOU)
stopSigGoroutine := make(chan struct{})
sigGoRoutineDone := make(chan struct{})
// Set up intCh.
ev.intCh = make(chan struct{})
sigCh := make(chan os.Signal)
signal.Notify(sigCh, syscall.SIGINT, syscall.SIGQUIT)
go func() {
closedIntCh := false
loop:
for {
select {
case <-sigCh:
if !closedIntCh {
close(ev.intCh)
closedIntCh = true
}
case <-stopSigGoroutine:
break loop
}
}
ev.intCh = nil
signal.Stop(sigCh)
close(sigGoRoutineDone)
}()
ret, err := ev.eval(op, ports, name, text)
close(outCh)
<-outDone
close(stopSigGoroutine)
<-sigGoRoutineDone
if !ret {
fmt.Println(falseIndicator)
}
// Put myself in foreground, in case some command has put me in background.
// XXX Should probably use fd of /dev/tty instead of 0.
if sys.IsATTY(0) {
err := sys.Tcsetpgrp(0, syscall.Getpgrp())
if err != nil {
fmt.Println("failed to put myself in foreground:", err)
}
}
return err
}
func (cp *compiler) pipeline(n *parse.Pipeline) Op {
ops := cp.forms(n.Forms)
p := n.Begin()
return func(ec *EvalCtx) {
var nextIn *Port
errorChans := make([]chan Error, len(ops))
// For each form, create a dedicated evalCtx and run asynchronously
for i, op := range ops {
newEc := ec.fork(fmt.Sprintf("form op %v", op))
if i > 0 {
newEc.ports[0] = nextIn
}
if i < len(ops)-1 {
// Each internal port pair consists of a (byte) pipe pair and a
// channel.
// os.Pipe sets O_CLOEXEC, which is what we want.
reader, writer, e := os.Pipe()
if e != nil {
ec.errorf(p, "failed to create pipe: %s", e)
}
ch := make(chan Value, pipelineChanBufferSize)
newEc.ports[1] = &Port{
File: writer, Chan: ch, CloseFile: true, CloseChan: true}
nextIn = &Port{
File: reader, Chan: ch, CloseFile: true, CloseChan: false}
}
thisOp := op
errorChans[i] = make(chan Error)
thisErrorChan := errorChans[i]
go func() {
err := newEc.PEval(thisOp)
// Logger.Printf("closing ports of %s", newEc.context)
ClosePorts(newEc.ports)
thisErrorChan <- Error{err}
}()
}
intCh := make(chan os.Signal)
signal.Notify(intCh, syscall.SIGINT)
interrupted := make(chan struct{})
cancel := make(chan struct{}, 1)
go func() {
// When SIGINT is received, sleep for InterruptDeadline before the
// closing interrupted channel.
select {
case <-intCh:
case <-cancel:
return
}
select {
case <-time.After(InterruptDeadline):
case <-cancel:
return
}
close(interrupted)
}()
// Wait for all forms to finish and collect error returns, unless an
// interrupt was received and the form didn't quit within
// InterruptDeadline.
errors := make([]Error, len(ops))
for i, errorChan := range errorChans {
select {
case errors[i] = <-errorChan:
case <-interrupted:
errors[i] = Error{ErrStillRunning}
}
}
// Make sure the SIGINT listener exits.
close(cancel)
signal.Stop(intCh)
// Make sure I am in foreground.
if PutInForeground && sys.IsATTY(0) {
err := sys.Tcsetpgrp(0, syscall.Getpgrp())
if err != nil {
throw(err)
}
}
if !allok(errors) {
if len(errors) == 1 {
throw(errors[0].inner)
} else {
throw(multiError{errors})
}
}
}
}
