diff options
Diffstat (limited to 'vendor/golang.org/x/term/terminal.go')
| -rw-r--r-- | vendor/golang.org/x/term/terminal.go | 86 |
1 files changed, 74 insertions, 12 deletions
diff --git a/vendor/golang.org/x/term/terminal.go b/vendor/golang.org/x/term/terminal.go index f636667..bddb2e2 100644 --- a/vendor/golang.org/x/term/terminal.go +++ b/vendor/golang.org/x/term/terminal.go @@ -6,6 +6,7 @@ package term import ( "bytes" + "fmt" "io" "runtime" "strconv" @@ -36,6 +37,26 @@ var vt100EscapeCodes = EscapeCodes{ Reset: []byte{keyEscape, '[', '0', 'm'}, } +// A History provides a (possibly bounded) queue of input lines read by [Terminal.ReadLine]. +type History interface { + // Add will be called by [Terminal.ReadLine] to add + // a new, most recent entry to the history. + // It is allowed to drop any entry, including + // the entry being added (e.g., if it's deemed an invalid entry), + // the least-recent entry (e.g., to keep the history bounded), + // or any other entry. + Add(entry string) + + // Len returns the number of entries in the history. + Len() int + + // At returns an entry from the history. + // Index 0 is the most-recently added entry and + // index Len()-1 is the least-recently added entry. + // If index is < 0 or >= Len(), it panics. + At(idx int) string +} + // Terminal contains the state for running a VT100 terminal that is capable of // reading lines of input. type Terminal struct { @@ -44,6 +65,8 @@ type Terminal struct { // bytes, as an index into |line|). If it returns ok=false, the key // press is processed normally. Otherwise it returns a replacement line // and the new cursor position. + // + // This will be disabled during ReadPassword. AutoCompleteCallback func(line string, pos int, key rune) (newLine string, newPos int, ok bool) // Escape contains a pointer to the escape codes for this terminal. @@ -84,9 +107,14 @@ type Terminal struct { remainder []byte inBuf [256]byte - // history contains previously entered commands so that they can be - // accessed with the up and down keys. - history stRingBuffer + // History records and retrieves lines of input read by [ReadLine] which + // a user can retrieve and navigate using the up and down arrow keys. + // + // It is not safe to call ReadLine concurrently with any methods on History. + // + // [NewTerminal] sets this to a default implementation that records the + // last 100 lines of input. + History History // historyIndex stores the currently accessed history entry, where zero // means the immediately previous entry. historyIndex int @@ -109,6 +137,7 @@ func NewTerminal(c io.ReadWriter, prompt string) *Terminal { termHeight: 24, echo: true, historyIndex: -1, + History: &stRingBuffer{}, } } @@ -117,6 +146,7 @@ const ( keyCtrlD = 4 keyCtrlU = 21 keyEnter = '\r' + keyLF = '\n' keyEscape = 27 keyBackspace = 127 keyUnknown = 0xd800 /* UTF-16 surrogate area */ + iota @@ -448,10 +478,27 @@ func visualLength(runes []rune) int { return length } +// histroryAt unlocks the terminal and relocks it while calling History.At. +func (t *Terminal) historyAt(idx int) (string, bool) { + t.lock.Unlock() // Unlock to avoid deadlock if History methods use the output writer. + defer t.lock.Lock() // panic in At (or Len) protection. + if idx < 0 || idx >= t.History.Len() { + return "", false + } + return t.History.At(idx), true +} + +// historyAdd unlocks the terminal and relocks it while calling History.Add. +func (t *Terminal) historyAdd(entry string) { + t.lock.Unlock() // Unlock to avoid deadlock if History methods use the output writer. + defer t.lock.Lock() // panic in Add protection. + t.History.Add(entry) +} + // handleKey processes the given key and, optionally, returns a line of text // that the user has entered. func (t *Terminal) handleKey(key rune) (line string, ok bool) { - if t.pasteActive && key != keyEnter { + if t.pasteActive && key != keyEnter && key != keyLF { t.addKeyToLine(key) return } @@ -495,7 +542,7 @@ func (t *Terminal) handleKey(key rune) (line string, ok bool) { t.pos = len(t.line) t.moveCursorToPos(t.pos) case keyUp: - entry, ok := t.history.NthPreviousEntry(t.historyIndex + 1) + entry, ok := t.historyAt(t.historyIndex + 1) if !ok { return "", false } @@ -514,14 +561,14 @@ func (t *Terminal) handleKey(key rune) (line string, ok bool) { t.setLine(runes, len(runes)) t.historyIndex-- default: - entry, ok := t.history.NthPreviousEntry(t.historyIndex - 1) + entry, ok := t.historyAt(t.historyIndex - 1) if ok { t.historyIndex-- runes := []rune(entry) t.setLine(runes, len(runes)) } } - case keyEnter: + case keyEnter, keyLF: t.moveCursorToPos(len(t.line)) t.queue([]rune("\r\n")) line = string(t.line) @@ -692,6 +739,8 @@ func (t *Terminal) Write(buf []byte) (n int, err error) { // ReadPassword temporarily changes the prompt and reads a password, without // echo, from the terminal. +// +// The AutoCompleteCallback is disabled during this call. func (t *Terminal) ReadPassword(prompt string) (line string, err error) { t.lock.Lock() defer t.lock.Unlock() @@ -699,6 +748,11 @@ func (t *Terminal) ReadPassword(prompt string) (line string, err error) { oldPrompt := t.prompt t.prompt = []rune(prompt) t.echo = false + oldAutoCompleteCallback := t.AutoCompleteCallback + t.AutoCompleteCallback = nil + defer func() { + t.AutoCompleteCallback = oldAutoCompleteCallback + }() line, err = t.readLine() @@ -759,6 +813,10 @@ func (t *Terminal) readLine() (line string, err error) { if !t.pasteActive { lineIsPasted = false } + // If we have CR, consume LF if present (CRLF sequence) to avoid returning an extra empty line. + if key == keyEnter && len(rest) > 0 && rest[0] == keyLF { + rest = rest[1:] + } line, lineOk = t.handleKey(key) } if len(rest) > 0 { @@ -772,7 +830,7 @@ func (t *Terminal) readLine() (line string, err error) { if lineOk { if t.echo { t.historyIndex = -1 - t.history.Add(line) + t.historyAdd(line) } if lineIsPasted { err = ErrPasteIndicator @@ -929,19 +987,23 @@ func (s *stRingBuffer) Add(a string) { } } -// NthPreviousEntry returns the value passed to the nth previous call to Add. +func (s *stRingBuffer) Len() int { + return s.size +} + +// At returns the value passed to the nth previous call to Add. // If n is zero then the immediately prior value is returned, if one, then the // next most recent, and so on. If such an element doesn't exist then ok is // false. -func (s *stRingBuffer) NthPreviousEntry(n int) (value string, ok bool) { +func (s *stRingBuffer) At(n int) string { if n < 0 || n >= s.size { - return "", false + panic(fmt.Sprintf("term: history index [%d] out of range [0,%d)", n, s.size)) } index := s.head - n if index < 0 { index += s.max } - return s.entries[index], true + return s.entries[index] } // readPasswordLine reads from reader until it finds \n or io.EOF. |