func testCodepage(t *testing.T, name string, inReader, outReader func(io.Reader) io.Reader) {
data := make([]byte, 256)
for i := range data {
data[i] = byte(i)
}
inr := inReader(bytes.NewBuffer(data))
r, err := charset.NewReader(name, inr)
if err != nil {
t.Fatalf("cannot make reader for charset %q: %v", name, err)
}
outr := outReader(r)
r = outr
var outbuf bytes.Buffer
w, err := charset.NewWriter(name, &outbuf)
if err != nil {
t.Fatalf("cannot make writer for charset %q: %v", name, err)
}
_, err = io.Copy(w, r)
if err != nil {
t.Fatalf("copy failed: %v", err)
}
err = w.Close()
if err != nil {
t.Fatalf("close failed: %v", err)
}
if len(outbuf.Bytes()) != len(data) {
t.Fatalf("short result of roundtrip, charset %q, readers %T, %T; expected 256, got %d", name, inr, outr, len(outbuf.Bytes()))
}
for i, x := range outbuf.Bytes() {
if data[i] != x {
t.Fatalf("charset %q, round trip expected %d, got %d", name, i, data[i])
}
}
}
func main() {
flag.Usage = func() {
fmt.Fprintf(os.Stderr, "usage: tcs [-l] [-v] [charset]\n")
fmt.Fprintf(os.Stderr, "\ttcs [-f charset] [-t charset] [file]\n")
}
flag.Parse()
if *listFlag {
cs := ""
switch flag.NArg() {
case 1:
cs = flag.Arg(0)
case 0:
default:
flag.Usage()
}
listCharsets(*verboseFlag, cs)
return
}
var f *os.File
switch flag.NArg() {
case 0:
f = os.Stdin
case 1:
var err error
f, err = os.Open(flag.Arg(0))
if err != nil {
fatalf("cannot open %q: %v", err)
}
}
r, err := charset.NewReader(*fromCharset, f)
if err != nil {
fatalf("cannot translate from %q: %v", *fromCharset, err)
}
w, err := charset.NewWriter(*toCharset, os.Stdout)
if err != nil {
fatalf("cannot translate to %q: ", err)
}
_, err = io.Copy(w, r)
if err != nil {
fatalf("%v", err)
}
}