.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.0.0-20201028153306-37f0764111ff/internal/lsp/browser/browser.go

   1 // Copyright 2016 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // Package browser provides utilities for interacting with users' browsers.
   6 package browser
   7
   8 import (
   9         "os"
  10         "os/exec"
  11         "runtime"
  12         "time"
  13 )
  14
  15 // Commands returns a list of possible commands to use to open a url.
  16 func Commands() [][]string {
  17         var cmds [][]string
  18         if exe := os.Getenv("BROWSER"); exe != "" {
  19                 cmds = append(cmds, []string{exe})
  20         }
  21         switch runtime.GOOS {
  22         case "darwin":
  23                 cmds = append(cmds, []string{"/usr/bin/open"})
  24         case "windows":
  25                 cmds = append(cmds, []string{"cmd", "/c", "start"})
  26         default:
  27                 if os.Getenv("DISPLAY") != "" {
  28                         // xdg-open is only for use in a desktop environment.
  29                         cmds = append(cmds, []string{"xdg-open"})
  30                 }
  31         }
  32         cmds = append(cmds,
  33                 []string{"chrome"},
  34                 []string{"google-chrome"},
  35                 []string{"chromium"},
  36                 []string{"firefox"},
  37         )
  38         return cmds
  39 }
  40
  41 // Open tries to open url in a browser and reports whether it succeeded.
  42 func Open(url string) bool {
  43         for _, args := range Commands() {
  44                 cmd := exec.Command(args[0], append(args[1:], url)...)
  45                 if cmd.Start() == nil && appearsSuccessful(cmd, 3*time.Second) {
  46                         return true
  47                 }
  48         }
  49         return false
  50 }
  51
  52 // appearsSuccessful reports whether the command appears to have run successfully.
  53 // If the command runs longer than the timeout, it's deemed successful.
  54 // If the command runs within the timeout, it's deemed successful if it exited cleanly.
  55 func appearsSuccessful(cmd *exec.Cmd, timeout time.Duration) bool {
  56         errc := make(chan error, 1)
  57         go func() {
  58                 errc <- cmd.Wait()
  59         }()
  60
  61         select {
  62         case <-time.After(timeout):
  63                 return true
  64         case err := <-errc:
  65                 return err == nil
  66         }
  67 }