1// Mostly copied from Go's src/cmd/gofmt: 2// Copyright 2009 The Go Authors. All rights reserved. 3// Use of this source code is governed by a BSD-style 4// license that can be found in the LICENSE file. 5 6package main 7 8import ( 9 "bytes" 10 "flag" 11 "fmt" 12 "github.com/google/blueprint/parser" 13 "io" 14 "io/ioutil" 15 "os" 16 "os/exec" 17 "path/filepath" 18) 19 20var ( 21 // main operation modes 22 list = flag.Bool("l", false, "list files whose formatting differs from bpfmt's") 23 write = flag.Bool("w", false, "write result to (source) file instead of stdout") 24 doDiff = flag.Bool("d", false, "display diffs instead of rewriting files") 25 sortLists = flag.Bool("s", false, "sort arrays") 26) 27 28var ( 29 exitCode = 0 30) 31 32func report(err error) { 33 fmt.Fprintln(os.Stderr, err) 34 exitCode = 2 35} 36 37func usage() { 38 fmt.Fprintf(os.Stderr, "usage: bpfmt [flags] [path ...]\n") 39 flag.PrintDefaults() 40 os.Exit(2) 41} 42 43// If in == nil, the source is the contents of the file with the given filename. 44func processFile(filename string, in io.Reader, out io.Writer) error { 45 if in == nil { 46 f, err := os.Open(filename) 47 if err != nil { 48 return err 49 } 50 defer f.Close() 51 in = f 52 } 53 54 src, err := ioutil.ReadAll(in) 55 if err != nil { 56 return err 57 } 58 59 r := bytes.NewBuffer(src) 60 61 file, errs := parser.Parse(filename, r, parser.NewScope(nil)) 62 if len(errs) > 0 { 63 for _, err := range errs { 64 fmt.Fprintln(os.Stderr, err) 65 } 66 return fmt.Errorf("%d parsing errors", len(errs)) 67 } 68 69 if *sortLists { 70 parser.SortLists(file) 71 } 72 73 res, err := parser.Print(file) 74 if err != nil { 75 return err 76 } 77 78 if !bytes.Equal(src, res) { 79 // formatting has changed 80 if *list { 81 fmt.Fprintln(out, filename) 82 } 83 if *write { 84 err = ioutil.WriteFile(filename, res, 0644) 85 if err != nil { 86 return err 87 } 88 } 89 if *doDiff { 90 data, err := diff(src, res) 91 if err != nil { 92 return fmt.Errorf("computing diff: %s", err) 93 } 94 fmt.Printf("diff %s bpfmt/%s\n", filename, filename) 95 out.Write(data) 96 } 97 } 98 99 if !*list && !*write && !*doDiff { 100 _, err = out.Write(res) 101 } 102 103 return err 104} 105 106func visitFile(path string, f os.FileInfo, err error) error { 107 if err == nil && f.Name() == "Blueprints" { 108 err = processFile(path, nil, os.Stdout) 109 } 110 if err != nil { 111 report(err) 112 } 113 return nil 114} 115 116func walkDir(path string) { 117 filepath.Walk(path, visitFile) 118} 119 120func main() { 121 flag.Parse() 122 123 if flag.NArg() == 0 { 124 if *write { 125 fmt.Fprintln(os.Stderr, "error: cannot use -w with standard input") 126 exitCode = 2 127 return 128 } 129 if err := processFile("<standard input>", os.Stdin, os.Stdout); err != nil { 130 report(err) 131 } 132 return 133 } 134 135 for i := 0; i < flag.NArg(); i++ { 136 path := flag.Arg(i) 137 switch dir, err := os.Stat(path); { 138 case err != nil: 139 report(err) 140 case dir.IsDir(): 141 walkDir(path) 142 default: 143 if err := processFile(path, nil, os.Stdout); err != nil { 144 report(err) 145 } 146 } 147 } 148} 149 150func diff(b1, b2 []byte) (data []byte, err error) { 151 f1, err := ioutil.TempFile("", "bpfmt") 152 if err != nil { 153 return 154 } 155 defer os.Remove(f1.Name()) 156 defer f1.Close() 157 158 f2, err := ioutil.TempFile("", "bpfmt") 159 if err != nil { 160 return 161 } 162 defer os.Remove(f2.Name()) 163 defer f2.Close() 164 165 f1.Write(b1) 166 f2.Write(b2) 167 168 data, err = exec.Command("diff", "-u", f1.Name(), f2.Name()).CombinedOutput() 169 if len(data) > 0 { 170 // diff exits with a non-zero status when the files don't match. 171 // Ignore that failure as long as we get output. 172 err = nil 173 } 174 return 175 176} 177