diff options
Diffstat (limited to 'vendor/github.com/MichaelMure/gocui/escape.go')
-rw-r--r-- | vendor/github.com/MichaelMure/gocui/escape.go | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/vendor/github.com/MichaelMure/gocui/escape.go b/vendor/github.com/MichaelMure/gocui/escape.go new file mode 100644 index 00000000..ec31bbe0 --- /dev/null +++ b/vendor/github.com/MichaelMure/gocui/escape.go @@ -0,0 +1,229 @@ +// Copyright 2014 The gocui Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package gocui + +import ( + "errors" + "strconv" +) + +type escapeInterpreter struct { + state escapeState + curch rune + csiParam []string + curFgColor, curBgColor Attribute + mode OutputMode +} + +type escapeState int + +const ( + stateNone escapeState = iota + stateEscape + stateCSI + stateParams +) + +var ( + errNotCSI = errors.New("Not a CSI escape sequence") + errCSIParseError = errors.New("CSI escape sequence parsing error") + errCSITooLong = errors.New("CSI escape sequence is too long") +) + +// runes in case of error will output the non-parsed runes as a string. +func (ei *escapeInterpreter) runes() []rune { + switch ei.state { + case stateNone: + return []rune{0x1b} + case stateEscape: + return []rune{0x1b, ei.curch} + case stateCSI: + return []rune{0x1b, '[', ei.curch} + case stateParams: + ret := []rune{0x1b, '['} + for _, s := range ei.csiParam { + ret = append(ret, []rune(s)...) + ret = append(ret, ';') + } + return append(ret, ei.curch) + } + return nil +} + +// newEscapeInterpreter returns an escapeInterpreter that will be able to parse +// terminal escape sequences. +func newEscapeInterpreter(mode OutputMode) *escapeInterpreter { + ei := &escapeInterpreter{ + state: stateNone, + curFgColor: ColorDefault, + curBgColor: ColorDefault, + mode: mode, + } + return ei +} + +// reset sets the escapeInterpreter in initial state. +func (ei *escapeInterpreter) reset() { + ei.state = stateNone + ei.curFgColor = ColorDefault + ei.curBgColor = ColorDefault + ei.csiParam = nil +} + +// parseOne parses a rune. If isEscape is true, it means that the rune is part +// of an escape sequence, and as such should not be printed verbatim. Otherwise, +// it's not an escape sequence. +func (ei *escapeInterpreter) parseOne(ch rune) (isEscape bool, err error) { + // Sanity checks + if len(ei.csiParam) > 20 { + return false, errCSITooLong + } + if len(ei.csiParam) > 0 && len(ei.csiParam[len(ei.csiParam)-1]) > 255 { + return false, errCSITooLong + } + + ei.curch = ch + + switch ei.state { + case stateNone: + if ch == 0x1b { + ei.state = stateEscape + return true, nil + } + return false, nil + case stateEscape: + if ch == '[' { + ei.state = stateCSI + return true, nil + } + return false, errNotCSI + case stateCSI: + switch { + case ch >= '0' && ch <= '9': + ei.csiParam = append(ei.csiParam, "") + case ch == 'm': + ei.csiParam = append(ei.csiParam, "0") + default: + return false, errCSIParseError + } + ei.state = stateParams + fallthrough + case stateParams: + switch { + case ch >= '0' && ch <= '9': + ei.csiParam[len(ei.csiParam)-1] += string(ch) + return true, nil + case ch == ';': + ei.csiParam = append(ei.csiParam, "") + return true, nil + case ch == 'm': + var err error + switch ei.mode { + case OutputNormal: + err = ei.outputNormal() + case Output256: + err = ei.output256() + } + if err != nil { + return false, errCSIParseError + } + + ei.state = stateNone + ei.csiParam = nil + return true, nil + default: + return false, errCSIParseError + } + } + return false, nil +} + +// outputNormal provides 8 different colors: +// black, red, green, yellow, blue, magenta, cyan, white +func (ei *escapeInterpreter) outputNormal() error { + for _, param := range ei.csiParam { + p, err := strconv.Atoi(param) + if err != nil { + return errCSIParseError + } + + switch { + case p >= 30 && p <= 37: + ei.curFgColor = Attribute(p - 30 + 1) + case p == 39: + ei.curFgColor = ColorDefault + case p >= 40 && p <= 47: + ei.curBgColor = Attribute(p - 40 + 1) + case p == 49: + ei.curBgColor = ColorDefault + case p == 1: + ei.curFgColor |= AttrBold + case p == 4: + ei.curFgColor |= AttrUnderline + case p == 7: + ei.curFgColor |= AttrReverse + case p == 0: + ei.curFgColor = ColorDefault + ei.curBgColor = ColorDefault + } + } + + return nil +} + +// output256 allows you to leverage the 256-colors terminal mode: +// 0x01 - 0x08: the 8 colors as in OutputNormal +// 0x09 - 0x10: Color* | AttrBold +// 0x11 - 0xe8: 216 different colors +// 0xe9 - 0x1ff: 24 different shades of grey +func (ei *escapeInterpreter) output256() error { + if len(ei.csiParam) < 3 { + return ei.outputNormal() + } + + mode, err := strconv.Atoi(ei.csiParam[1]) + if err != nil { + return errCSIParseError + } + if mode != 5 { + return ei.outputNormal() + } + + fgbg, err := strconv.Atoi(ei.csiParam[0]) + if err != nil { + return errCSIParseError + } + color, err := strconv.Atoi(ei.csiParam[2]) + if err != nil { + return errCSIParseError + } + + switch fgbg { + case 38: + ei.curFgColor = Attribute(color + 1) + + for _, param := range ei.csiParam[3:] { + p, err := strconv.Atoi(param) + if err != nil { + return errCSIParseError + } + + switch { + case p == 1: + ei.curFgColor |= AttrBold + case p == 4: + ei.curFgColor |= AttrUnderline + case p == 7: + ei.curFgColor |= AttrReverse + } + } + case 48: + ei.curBgColor = Attribute(color + 1) + default: + return errCSIParseError + } + + return nil +} |