Gocui在寻呼机程序后中断
问题描述：
I have a program based on the gocui library, which has a keybinding with a function which generates text and sends it to the pager's stdin. But after closing the pager, all previous gocui interface becomes broken, but program is still working.
So how can I safely return from pager to the gocui mode and continue the program?
Simplified example, here.
package main
import (
"fmt"
"log"
"os/exec"
"os"
"strings"
"github.com/jroimartin/gocui"
"time"
"sync"
"bytes"
)
var (
done = make(chan struct{})
wg sync.WaitGroup
)
func main() {
g, err := gocui.NewGui(gocui.OutputNormal)
if err != nil {
log.Panicln(err)
}
defer g.Close()
g.SetManagerFunc(layout)
if err := g.SetKeybinding("", gocui.KeyCtrlC, gocui.ModNone, quit); err != nil {
log.Panicln(err)
}
if err := g.SetKeybinding("", gocui.KeySpace, gocui.ModNone, pager); err != nil {
log.Panicln(err)
}
wg.Add(1)
go showTime(g)
if err := g.MainLoop(); err != nil && err != gocui.ErrQuit {
log.Panicln(err)
}
wg.Wait()
}
func layout(g *gocui.Gui) error {
maxX, _ := g.Size()
if v, err := g.SetView("main", -1, -1, maxX/2-1, 4); err != nil {
if err != gocui.ErrUnknownView {
return err
}
fmt.Fprintln(v, time.Now().Format("2006-01-02 15:04:05.000"))
v.Frame = false
}
return nil
}
func pager(g *gocui.Gui, v *gocui.View) error {
var buf bytes.Buffer
for i:=0; i < 10; i++ {
buf.WriteString(fmt.Sprintf("%d -- %s %s
", i, "example", "text"))
}
cmd := exec.Command("less")
cmd.Stdin = strings.NewReader(buf.String())
cmd.Stdout = os.Stdout
err := cmd.Run()
return err
}
func showTime(g *gocui.Gui) {
defer wg.Done()
for {
select {
case <-done:
return
case <-time.After(1 * time.Second):
t := time.Now()
g.Update(func(g *gocui.Gui) error {
v, err := g.View("main")
if err != nil {
return err
}
v.Clear()
fmt.Fprintln(v, t.Format("2006-01-02 15:04:05.000"))
return nil
})
}
}
}
func quit(g *gocui.Gui, v *gocui.View) error {
return gocui.ErrQuit
}
答
Final example is below, it has additional things and in some places looks dirty, but it works in general.
package main
import (
"fmt"
"log"
"os/exec"
"os"
"github.com/jroimartin/gocui"
"time"
"sync"
)
var (
do_quit = make(chan int)
do_pause = make(chan int)
show_aux = false
wg sync.WaitGroup
)
func main() {
for {
// DEBUG: fmt.Println("start gui")
g, err := gocui.NewGui(gocui.OutputNormal)
if err != nil {
log.Panicln(err)
}
defer g.Close()
g.SetManagerFunc(layout)
setKeys(g)
wg.Add(1)
go showTime(g)
if err := g.MainLoop(); err != nil && err != gocui.ErrQuit {
continue // restart gui if something goes wrong
}
wg.Wait()
}
}
func layout(g *gocui.Gui) error {
maxX, _ := g.Size()
if v, err := g.SetView("main", -1, -1, maxX/2-1, 4); err != nil {
if err != gocui.ErrUnknownView {
return err
}
fmt.Fprintf(v, "sys: %s
", time.Now().Format("2006-01-02 15:04:05.000"))
v.Frame = false
}
return nil
}
func runPager(g *gocui.Gui, v *gocui.View) error {
do_quit <-1
g.Close()
cmd := exec.Command("less", "/etc/sysctl.conf")
cmd.Stdout = os.Stdout
err := cmd.Run()
return err
}
func runEditor(g *gocui.Gui, v *gocui.View) error {
do_quit <-1
g.Close()
cmd := exec.Command("vi", "/tmp/strace.out")
cmd.Stdin = os.Stdin
cmd.Stdout = os.Stdout
err := cmd.Run()
return err
}
func runPsql(g *gocui.Gui, v *gocui.View) error {
do_quit <-1
g.Close()
cmd := exec.Command("psql", "-U", "postgres")
cmd.Stdin = os.Stdin
cmd.Stdout = os.Stdout
err := cmd.Run()
return err
}
func showAux(g *gocui.Gui, _ *gocui.View) error {
if !show_aux {
maxX, maxY := g.Size()
if v, err := g.SetView("aux", -1, 3*maxY/5-1, maxX-1, maxY-1); err != nil {
if err != gocui.ErrUnknownView {
return err
}
fmt.Fprintln(v, "")
v.Frame = false
}
} else {
g.DeleteView("aux")
}
show_aux = !show_aux
return nil
}
func showTime(g *gocui.Gui) {
var pause = false
defer wg.Done()
for {
select {
case <-do_pause:
pause = !pause
case <-do_quit:
return
case <-time.After(1 * time.Second):
if pause { continue }
g.Update(func(g *gocui.Gui) error {
v, err := g.View("main")
if err != nil {
return err
}
v.Clear()
fmt.Fprintf(v, "sys: %s
", time.Now().Format("2006-01-02 15:04:05.000"))
if show_aux {
v, err := g.View("aux")
if err != nil {
return err
}
v.Clear()
fmt.Fprintf(v, "aux: %s
", time.Now().Format("2006-01-02 15:04:05.000"))
}
return nil
})
}
}
}
func doQuit(g *gocui.Gui, v *gocui.View) error {
do_quit <- 1
g.Close()
os.Exit(0)
return gocui.ErrQuit
}
func setKeys(g *gocui.Gui) {
if err := g.SetKeybinding("", gocui.KeyCtrlQ, gocui.ModNone, doQuit); err != nil {
log.Panicln(err)
}
if err := g.SetKeybinding("", 'c', gocui.ModNone, runPager); err != nil {
log.Panicln(err)
}
if err := g.SetKeybinding("", 'e', gocui.ModNone, runEditor); err != nil {
log.Panicln(err)
}
if err := g.SetKeybinding("", 'p', gocui.ModNone, runPsql); err != nil {
log.Panicln(err)
}
if err := g.SetKeybinding("", 'b', gocui.ModNone, showAux); err != nil {
log.Panicln(err)
}
}