59 lines
1.6 KiB
Go
59 lines
1.6 KiB
Go
// +build linux,!baremetal darwin
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// Package rawterm provides some sort of raw terminal interface, both on hosted
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// systems and baremetal. It is intended only for use by examples.
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//
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// Newlines are always LF (not CR or CRLF). While terminals generally use a
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// different format (CR when pressing the enter key and CRLF for newline) the
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// format returned by Getchar and expected as input by Putchar is a single LF
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// as newline symbol.
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package rawterm
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import (
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"os"
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"golang.org/x/crypto/ssh/terminal"
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)
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var terminalState *terminal.State
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// Getchar returns a single character from stdin, or a serial input. Newlines
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// are encoded with a single LF ('\n').
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func Getchar() byte {
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var b [1]byte
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os.Stdin.Read(b[:])
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if b[0] == '\r' {
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return '\n'
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}
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return b[0]
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}
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// Putchar writes a single character to the terminal. Newlines are expected to
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// be encoded as LF symbols ('\n').
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func Putchar(ch byte) {
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if ch == '\n' {
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// Terminals expect CRLF.
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Putchar('\r')
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}
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b := [1]byte{ch}
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os.Stdout.Write(b[:])
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}
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// Configure initializes the terminal for use by raw reading/writing (using
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// Getchar/Putchar). It must be restored after use with Restore. You can do this
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// with the following code:
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//
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// rawterm.Configure()
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// defer rawterm.Restore()
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// // use raw terminal features
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func Configure() {
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terminalState, _ = terminal.MakeRaw(0)
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}
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// Restore restores the state to before a call to Configure. It must be called
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// after a call to Configure to restore the terminal state, and must only be
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// called after a call to Configure.
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func Restore() {
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terminal.Restore(0, terminalState)
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}
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