cmd/geth, cmd/utils: improve input handling

These changes make prompting behave consistently on all platforms:

* The input buffer is now global.
  Buffering was previously set up for each prompt, which can cause weird
  behaviour, e.g. when running "geth account update <input.txt" where
  input.txt contains three lines. In this case, the first password
  prompt would fill up the buffer with all lines and then use only the
  first one.

* Print the "unsupported terminal" warning only once.
  Now that stdin prompting has global state, we can use it to track
  the warning there.

* Work around small liner issues, particularly on Windows.
  Prompting didn't work under most of the third-party terminal emulators
  on Windows because liner assumes line editing is always available.

1 files changed, 5 insertions, 4 deletions

diff --git a/cmd/utils/jeth.go b/cmd/utils/jeth.go
index 35fcd4bed..708d457c6 100644
--- a/cmd/utils/jeth.go
+++ b/cmd/utils/jeth.go
@@ -75,8 +75,9 @@ func (self *Jeth) UnlockAccount(call otto.FunctionCall) (response otto.Value) {
 	// if password is not given or as null value -> ask user for password
 	if call.Argument(1).IsUndefined() || call.Argument(1).IsNull() {
 		fmt.Printf("Unlock account %s\n", account)
-		if password, err := PromptPassword("Passphrase: ", true); err == nil {
-			passwd, _ = otto.ToValue(password)
+		if input, err := Stdin.PasswordPrompt("Passphrase: "); err != nil {
+			return otto.FalseValue()
+			passwd, _ = otto.ToValue(input)
 		} else {
 			throwJSExeception(err.Error())
 		}
@@ -111,11 +112,11 @@ func (self *Jeth) NewAccount(call otto.FunctionCall) (response otto.Value) {
 	var passwd string
 	if len(call.ArgumentList) == 0 {
 		var err error
-		passwd, err = PromptPassword("Passphrase: ", true)
+		passwd, err = Stdin.PasswordPrompt("Passphrase: ")
 		if err != nil {
 			return otto.FalseValue()
 		}
-		passwd2, err := PromptPassword("Repeat passphrase: ", true)
+		passwd2, err := Stdin.PasswordPrompt("Repeat passphrase: ")
 		if err != nil {
 			return otto.FalseValue()
 		}