1 // Copyright 2012 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 main 6 7 import ( 8 "flag" 9 "fmt" 10 "os" 11 "strconv" 12 ) 13 14 // cmdtab records the available commands. 15 var cmdtab = []struct { 16 name string 17 f func() 18 }{ 19 {"banner", cmdbanner}, 20 {"bootstrap", cmdbootstrap}, 21 {"clean", cmdclean}, 22 {"env", cmdenv}, 23 {"install", cmdinstall}, 24 {"test", cmdtest}, 25 {"version", cmdversion}, 26 } 27 28 // The OS-specific main calls into the portable code here. 29 func xmain() { 30 if len(os.Args) < 2 { 31 usage() 32 } 33 cmd := os.Args[1] 34 os.Args = os.Args[1:] // for flag parsing during cmd 35 for _, ct := range cmdtab { 36 if ct.name == cmd { 37 flag.Usage = func() { 38 fmt.Fprintf(os.Stderr, "usage: go tool dist %s [options]\n", cmd) 39 flag.PrintDefaults() 40 os.Exit(2) 41 } 42 ct.f() 43 return 44 } 45 } 46 47 xprintf("unknown command %s\n", cmd) 48 usage() 49 } 50 51 func xflagparse(maxargs int) { 52 flag.Var((*count)(&vflag), "v", "verbosity") 53 flag.Parse() 54 if maxargs >= 0 && flag.NArg() > maxargs { 55 flag.Usage() 56 } 57 } 58 59 // count is a flag.Value that is like a flag.Bool and a flag.Int. 60 // If used as -name, it increments the count, but -name=x sets the count. 61 // Used for verbose flag -v. 62 type count int 63 64 func (c *count) String() string { 65 return fmt.Sprint(int(*c)) 66 } 67 68 func (c *count) Set(s string) error { 69 switch s { 70 case "true": 71 *c++ 72 case "false": 73 *c = 0 74 default: 75 n, err := strconv.Atoi(s) 76 if err != nil { 77 return fmt.Errorf("invalid count %q", s) 78 } 79 *c = count(n) 80 } 81 return nil 82 } 83 84 func (c *count) IsBoolFlag() bool { 85 return true 86 } 87
