cmd/acme: fix undo, fix wait chan mostly

Edit |date still hangs.

cmd/acme/acme.go

@@ -145,6 +145,8 @@ func main() {
 
 	ui.Textcomplete = fileloadpkg.Textcomplete
 	editpkg.Putfile = exec.Putfile
+	editpkg.BigLock = bigLock
+	editpkg.BigUnlock = bigUnlock
 	editpkg.Run = func(w *wind.Window, s string, rdir []rune) {
 		exec.Run(w, s, rdir, true, nil, nil, true)
 	}
@@ -583,14 +585,14 @@ func mousethread() {
  * This structure keeps a list of processes that have exited we haven't heard of.
  */
 
-type Pid struct {
-	pid  int
-	msg  string
-	next *Pid
+type Proc struct {
+	proc  *os.Process
+	err error
+	next *Proc
 }
 
 func waitthread() {
-	var pids *Pid
+	var pids *Proc
 
 	bigLock()
 	defer bigUnlock()
@@ -624,12 +626,13 @@ func waitthread() {
 				alog.Printf("Kill: no process %s\n", string(cmd))
 			}
 
-		case w := <-cwait:
+		case w := <-exec.Cwait:
+println("Cwait")
 			bigLock()
-			pid := w.pid
+			proc := w.Proc
 			var c, lc *exec.Command
 			for c = command; c != nil; c = c.Next {
-				if c.Pid == pid {
+				if c.Proc == proc {
 					if lc != nil {
 						lc.Next = c.Next
 					} else {
@@ -643,18 +646,18 @@ func waitthread() {
 			t := &wind.TheRow.Tag
 			wind.Textcommit(t, true)
 			if c == nil {
-				p := new(Pid)
-				p.pid = pid
-				p.msg = w.msg
+				p := new(Proc)
+				p.proc = proc
+				p.err = w.Err
 				p.next = pids
 				pids = p
 			} else {
 				if ui.Search(t, c.Name) {
 					wind.Textdelete(t, t.Q0, t.Q1, true)
 					wind.Textsetselect(t, 0, 0)
 				}
-				if w.msg[0] != 0 {
-					warning(c.Mntdir, "%s: exit %s\n", string(c.Name[:len(c.Name)-1]), w.msg)
+				if w.Err != nil {
+					warning(c.Mntdir, "%s: exit %s\n", string(c.Name[:len(c.Name)-1]), w.Err)
 				}
 				adraw.Display.Flush()
 			}
@@ -664,11 +667,11 @@ func waitthread() {
 		case c = <-exec.Ccommand:
 			bigLock()
 			// has this command already exited?
-			var lastp *Pid
+			var lastp *Proc
 			for p := pids; p != nil; p = p.next {
-				if p.pid == c.Pid {
-					if p.msg[0] != 0 {
-						warning(c.Mntdir, "%s\n", p.msg)
+				if p.proc == c.Proc {
+					if p.err != nil {
+						warning(c.Mntdir, "%s\n", p.err)
 					}
 					if lastp == nil {
 						pids = p.next
@@ -694,6 +697,7 @@ func waitthread() {
 	Freecmd:
 		if c != nil {
 			if c.IsEditCmd {
+println("Cedit send")
 				editpkg.Cedit <- 0
 			}
 			fsysdelid(c.Mntdir)

cmd/acme/dat.h.go

@@ -85,7 +85,6 @@ type Waitmsg struct {
 
 var (
 	cplumb     = make(chan *plumb.Message)
-	cwait      = make(chan *Waitmsg)
 	cxfidalloc = make(chan *Xfid) // TODO bidi
 	cxfidfree  = make(chan *Xfid)
 	cnewwindow = make(chan *wind.Window) // TODO bidi

cmd/acme/internal/edit/ecmd.go

@@ -31,6 +31,9 @@ import (
 	"9fans.net/go/cmd/acme/internal/wind"
 )
 
+var BigLock = func() {}
+var BigUnlock = func() {}
+
 var Glooping int
 var nest int
 var Enoname = "no file name given"
@@ -549,7 +552,9 @@ func runpipe(t *wind.Text, cmd rune, cr []rune, state int) {
 		wind.Winunlock(t.W)
 	}
 	wind.TheRow.Lk.Unlock()
+	BigUnlock()
 	<-Cedit
+	BigLock()
 	var q *util.QLock
 	/*
 	 * The editoutlk exists only so that we can tell when

cmd/acme/internal/exec/exec.go

@@ -48,6 +48,13 @@ var Fsysmount = func([]rune, [][]rune) *base.Mntdir { return nil }
 var Fsysdelid = func(*base.Mntdir) {}
 var Xfidlog = func(*wind.Window, string) {}
 
+var Cwait = make(chan Waitmsg)
+
+type Waitmsg struct {
+	Proc *os.Process
+	Err error
+}
+
 /*
  * These functions get called as:
  *
@@ -908,7 +915,7 @@ func tab(et, _, argt *wind.Text, _, _ bool, arg []rune) {
 	}
 }
 
-func runproc(win *wind.Window, s string, rdir []rune, newns bool, argaddr, xarg *string, c *Command, cpid chan int, iseditcmd bool) {
+func runproc(win *wind.Window, s string, rdir []rune, newns bool, argaddr, xarg *string, c *Command, cpid chan *os.Process, iseditcmd bool) {
 	t := strings.TrimLeft(s, " \n\t")
 	name := t
 	if i := strings.IndexAny(name, " \n\t"); i >= 0 {
@@ -1056,8 +1063,11 @@ func runproc(win *wind.Window, s string, rdir []rune, newns bool, argaddr, xarg
 		err := cmd.Start()
 		if err == nil {
 			if cpid != nil {
-				cpid <- cmd.Process.Pid // TODO(rsc): send cmd.Process
+				cpid <- cmd.Process // TODO(rsc): send cmd.Process
 			}
+			go func() {
+				Cwait <- Waitmsg{cmd.Process, cmd.Wait()}
+			}()
 			return
 		}
 		goto Fail
@@ -1086,7 +1096,7 @@ Hard:
 		err := cmd.Start()
 		if err == nil {
 			if cpid != nil {
-				cpid <- cmd.Process.Pid // TODO(rsc): send cmd.Process
+				cpid <- cmd.Process // TODO(rsc): send cmd.Process
 			}
 			return
 		}
@@ -1096,14 +1106,14 @@ Hard:
 
 Fail:
 	if cpid != nil { // TODO(rsc): is it always non-nil?
-		cpid <- 0
+		cpid <- nil
 	}
 }
 
-func runwaittask(c *Command, cpid chan int) {
-	c.Pid = <-cpid
+func runwaittask(c *Command, cproc chan *os.Process) {
+	c.Proc = <-cproc
 	c.av = nil
-	if c.Pid != 0 { // successful exec
+	if c.Proc != nil { // successful exec
 		Ccommand <- c
 	} else if c.IsEditCmd {
 		edit.Cedit <- 0
@@ -1115,10 +1125,10 @@ func Run(win *wind.Window, s string, rdir []rune, newns bool, argaddr, xarg *str
 		return
 	}
 	c := new(Command)
-	cpid := make(chan int, 0)
-	go runproc(win, s, rdir, newns, argaddr, xarg, c, cpid, iseditcmd)
+	cproc := make(chan *os.Process, 0)
+	go runproc(win, s, rdir, newns, argaddr, xarg, c, cproc, iseditcmd)
 	// mustn't block here because must be ready to answer mount() call in run()
-	go runwaittask(c, cpid)
+	go runwaittask(c, cproc)
 }
 
 func fsopenfd(fs *client.Fsys, name string, mode uint8) (*os.File, error) {
@@ -1148,7 +1158,7 @@ func fsopenfd(fs *client.Fsys, name string, mode uint8) (*os.File, error) {
 }
 
 type Command struct {
-	Pid       int
+	Proc       *os.Process
 	Name      []rune
 	text      string
 	av        []string

cmd/acme/internal/file/file.go

@@ -46,6 +46,8 @@ type File struct {
 	mod     bool
 }
 
+func (f *File) SetView(v View) { f.view = v }
+
 type View interface {
 	Insert(int, []rune)
 	Delete(int, int)

cmd/acme/internal/util/util.go

@@ -17,6 +17,7 @@ package util
 import (
 	"log"
 	"sync/atomic"
+	"sync"
 )
 
 func Min(a int, b int) int {
@@ -37,28 +38,43 @@ func Fatal(s string) {
 	log.Fatalf("acme: %s\n", s)
 }
 
+var locks struct {
+	mu sync.Mutex
+	cond sync.Cond
+}
+
+func init() {
+	locks.cond.L = &locks.mu
+}
+
 type QLock struct {
-	held chan bool
+	held uint32
 }
 
 func (l *QLock) TryLock() bool {
-	if l.held == nil {
-		panic("missing held")
-	}
-	select {
-	case l.held <- true:
-		return true
-	default:
-		return false
-	}
+	return atomic.CompareAndSwapUint32(&l.held, 0, 1)
 }
 
 func (l *QLock) Unlock() {
-	<-l.held
+	v := atomic.SwapUint32(&l.held, 0)
+	if v == 0 {
+		panic("Unlock of unlocked lock")
+	}
+	if v > 1 {
+		locks.cond.Broadcast()
+	}
 }
 
 func (l *QLock) Lock() {
-	l.held <- true
+	if atomic.AddUint32(&l.held, 1) == 1 {
+		return
+	}
+	locks.mu.Lock()
+	defer locks.mu.Unlock()
+
+	for atomic.AddUint32(&l.held, 1) != 1 {
+		locks.cond.Wait()
+	}
 }
 
 func Incref(p *uint32) { atomic.AddUint32(p, 1) }

cmd/acme/internal/wind/text.go

@@ -946,6 +946,7 @@ func ishtmlend(t *Text, q int, q0 *int) int {
 func fileaddtext(f *File, t *Text) *File {
 	if f == nil {
 		f = &File{File: new(file.File)}
+		f.File.SetView((*fileView)(f))
 		f.Unread = true
 	}
 	f.Text = append(f.Text, t)