/usr/share/gocode/src/github.com/peterh/liner/common.go is in golang-github-peterh-liner-dev 0.0~git20171122.3681c2a-3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 | /*
Package liner implements a simple command line editor, inspired by linenoise
(https://github.com/antirez/linenoise/). This package supports WIN32 in
addition to the xterm codes supported by everything else.
*/
package liner
import (
"bufio"
"container/ring"
"errors"
"fmt"
"io"
"strings"
"sync"
"unicode/utf8"
)
type commonState struct {
terminalSupported bool
outputRedirected bool
inputRedirected bool
history []string
historyMutex sync.RWMutex
completer WordCompleter
columns int
killRing *ring.Ring
ctrlCAborts bool
r *bufio.Reader
tabStyle TabStyle
multiLineMode bool
cursorRows int
maxRows int
shouldRestart ShouldRestart
needRefresh bool
}
// TabStyle is used to select how tab completions are displayed.
type TabStyle int
// Two tab styles are currently available:
//
// TabCircular cycles through each completion item and displays it directly on
// the prompt
//
// TabPrints prints the list of completion items to the screen after a second
// tab key is pressed. This behaves similar to GNU readline and BASH (which
// uses readline)
const (
TabCircular TabStyle = iota
TabPrints
)
// ErrPromptAborted is returned from Prompt or PasswordPrompt when the user presses Ctrl-C
// if SetCtrlCAborts(true) has been called on the State
var ErrPromptAborted = errors.New("prompt aborted")
// ErrNotTerminalOutput is returned from Prompt or PasswordPrompt if the
// platform is normally supported, but stdout has been redirected
var ErrNotTerminalOutput = errors.New("standard output is not a terminal")
// ErrInvalidPrompt is returned from Prompt or PasswordPrompt if the
// prompt contains any unprintable runes (including substrings that could
// be colour codes on some platforms).
var ErrInvalidPrompt = errors.New("invalid prompt")
// ErrInternal is returned when liner experiences an error that it cannot
// handle. For example, if the number of colums becomes zero during an
// active call to Prompt
var ErrInternal = errors.New("liner: internal error")
// KillRingMax is the max number of elements to save on the killring.
const KillRingMax = 60
// HistoryLimit is the maximum number of entries saved in the scrollback history.
const HistoryLimit = 1000
// ReadHistory reads scrollback history from r. Returns the number of lines
// read, and any read error (except io.EOF).
func (s *State) ReadHistory(r io.Reader) (num int, err error) {
s.historyMutex.Lock()
defer s.historyMutex.Unlock()
in := bufio.NewReader(r)
num = 0
for {
line, part, err := in.ReadLine()
if err == io.EOF {
break
}
if err != nil {
return num, err
}
if part {
return num, fmt.Errorf("line %d is too long", num+1)
}
if !utf8.Valid(line) {
return num, fmt.Errorf("invalid string at line %d", num+1)
}
num++
s.history = append(s.history, string(line))
if len(s.history) > HistoryLimit {
s.history = s.history[1:]
}
}
return num, nil
}
// WriteHistory writes scrollback history to w. Returns the number of lines
// successfully written, and any write error.
//
// Unlike the rest of liner's API, WriteHistory is safe to call
// from another goroutine while Prompt is in progress.
// This exception is to facilitate the saving of the history buffer
// during an unexpected exit (for example, due to Ctrl-C being invoked)
func (s *State) WriteHistory(w io.Writer) (num int, err error) {
s.historyMutex.RLock()
defer s.historyMutex.RUnlock()
for _, item := range s.history {
_, err := fmt.Fprintln(w, item)
if err != nil {
return num, err
}
num++
}
return num, nil
}
// AppendHistory appends an entry to the scrollback history. AppendHistory
// should be called iff Prompt returns a valid command.
func (s *State) AppendHistory(item string) {
s.historyMutex.Lock()
defer s.historyMutex.Unlock()
if len(s.history) > 0 {
if item == s.history[len(s.history)-1] {
return
}
}
s.history = append(s.history, item)
if len(s.history) > HistoryLimit {
s.history = s.history[1:]
}
}
// ClearHistory clears the scroollback history.
func (s *State) ClearHistory() {
s.historyMutex.Lock()
defer s.historyMutex.Unlock()
s.history = nil
}
// Returns the history lines starting with prefix
func (s *State) getHistoryByPrefix(prefix string) (ph []string) {
for _, h := range s.history {
if strings.HasPrefix(h, prefix) {
ph = append(ph, h)
}
}
return
}
// Returns the history lines matching the intelligent search
func (s *State) getHistoryByPattern(pattern string) (ph []string, pos []int) {
if pattern == "" {
return
}
for _, h := range s.history {
if i := strings.Index(h, pattern); i >= 0 {
ph = append(ph, h)
pos = append(pos, i)
}
}
return
}
// Completer takes the currently edited line content at the left of the cursor
// and returns a list of completion candidates.
// If the line is "Hello, wo!!!" and the cursor is before the first '!', "Hello, wo" is passed
// to the completer which may return {"Hello, world", "Hello, Word"} to have "Hello, world!!!".
type Completer func(line string) []string
// WordCompleter takes the currently edited line with the cursor position and
// returns the completion candidates for the partial word to be completed.
// If the line is "Hello, wo!!!" and the cursor is before the first '!', ("Hello, wo!!!", 9) is passed
// to the completer which may returns ("Hello, ", {"world", "Word"}, "!!!") to have "Hello, world!!!".
type WordCompleter func(line string, pos int) (head string, completions []string, tail string)
// SetCompleter sets the completion function that Liner will call to
// fetch completion candidates when the user presses tab.
func (s *State) SetCompleter(f Completer) {
if f == nil {
s.completer = nil
return
}
s.completer = func(line string, pos int) (string, []string, string) {
return "", f(string([]rune(line)[:pos])), string([]rune(line)[pos:])
}
}
// SetWordCompleter sets the completion function that Liner will call to
// fetch completion candidates when the user presses tab.
func (s *State) SetWordCompleter(f WordCompleter) {
s.completer = f
}
// SetTabCompletionStyle sets the behvavior when the Tab key is pressed
// for auto-completion. TabCircular is the default behavior and cycles
// through the list of candidates at the prompt. TabPrints will print
// the available completion candidates to the screen similar to BASH
// and GNU Readline
func (s *State) SetTabCompletionStyle(tabStyle TabStyle) {
s.tabStyle = tabStyle
}
// ModeApplier is the interface that wraps a representation of the terminal
// mode. ApplyMode sets the terminal to this mode.
type ModeApplier interface {
ApplyMode() error
}
// SetCtrlCAborts sets whether Prompt on a supported terminal will return an
// ErrPromptAborted when Ctrl-C is pressed. The default is false (will not
// return when Ctrl-C is pressed). Unsupported terminals typically raise SIGINT
// (and Prompt does not return) regardless of the value passed to SetCtrlCAborts.
func (s *State) SetCtrlCAborts(aborts bool) {
s.ctrlCAborts = aborts
}
// SetMultiLineMode sets whether line is auto-wrapped. The default is false (single line).
func (s *State) SetMultiLineMode(mlmode bool) {
s.multiLineMode = mlmode
}
// ShouldRestart is passed the error generated by readNext and returns true if
// the the read should be restarted or false if the error should be returned.
type ShouldRestart func(err error) bool
// SetShouldRestart sets the restart function that Liner will call to determine
// whether to retry the call to, or return the error returned by, readNext.
func (s *State) SetShouldRestart(f ShouldRestart) {
s.shouldRestart = f
}
func (s *State) promptUnsupported(p string) (string, error) {
if !s.inputRedirected || !s.terminalSupported {
fmt.Print(p)
}
linebuf, _, err := s.r.ReadLine()
if err != nil {
return "", err
}
return string(linebuf), nil
}
|