tcell/terminfo/dynamic/dynamic.go

428 lines
12 KiB
Go

// Copyright 2021 The TCell Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use file except in compliance with the License.
// You may obtain a copy of the license at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// The dynamic package is used to generate a terminal description dynamically,
// using infocmp. This is really a method of last resort, as the performance
// will be slow, and it requires a working infocmp. But, the hope is that it
// will assist folks who have to deal with a terminal description that isn't
// already built in. This requires infocmp to be in the user's path, and to
// support reasonably the -1 option.
package dynamic
import (
"bytes"
"errors"
"os/exec"
"regexp"
"strconv"
"strings"
"github.com/gdamore/tcell/v2/terminfo"
)
type termcap struct {
name string
desc string
aliases []string
bools map[string]bool
nums map[string]int
strs map[string]string
}
func (tc *termcap) getnum(s string) int {
return (tc.nums[s])
}
func (tc *termcap) getflag(s string) bool {
return (tc.bools[s])
}
func (tc *termcap) getstr(s string) string {
return (tc.strs[s])
}
const (
none = iota
control
escaped
)
var errNotAddressable = errors.New("terminal not cursor addressable")
func unescape(s string) string {
// Various escapes are in \x format. Control codes are
// encoded as ^M (carat followed by ASCII equivalent).
// escapes are: \e, \E - escape
// \0 NULL, \n \l \r \t \b \f \s for equivalent C escape.
buf := &bytes.Buffer{}
esc := none
for i := 0; i < len(s); i++ {
c := s[i]
switch esc {
case none:
switch c {
case '\\':
esc = escaped
case '^':
esc = control
default:
buf.WriteByte(c)
}
case control:
buf.WriteByte(c ^ 1<<6)
esc = none
case escaped:
switch c {
case 'E', 'e':
buf.WriteByte(0x1b)
case '0', '1', '2', '3', '4', '5', '6', '7':
if i+2 < len(s) && s[i+1] >= '0' && s[i+1] <= '7' && s[i+2] >= '0' && s[i+2] <= '7' {
buf.WriteByte(((c - '0') * 64) + ((s[i+1] - '0') * 8) + (s[i+2] - '0'))
i = i + 2
} else if c == '0' {
buf.WriteByte(0)
}
case 'n':
buf.WriteByte('\n')
case 'r':
buf.WriteByte('\r')
case 't':
buf.WriteByte('\t')
case 'b':
buf.WriteByte('\b')
case 'f':
buf.WriteByte('\f')
case 's':
buf.WriteByte(' ')
default:
buf.WriteByte(c)
}
esc = none
}
}
return (buf.String())
}
func (tc *termcap) setupterm(name string) error {
cmd := exec.Command("infocmp", "-1", name)
output := &bytes.Buffer{}
cmd.Stdout = output
tc.strs = make(map[string]string)
tc.bools = make(map[string]bool)
tc.nums = make(map[string]int)
if err := cmd.Run(); err != nil {
return err
}
// Now parse the output.
// We get comment lines (starting with "#"), followed by
// a header line that looks like "<name>|<alias>|...|<desc>"
// then capabilities, one per line, starting with a tab and ending
// with a comma and newline.
lines := strings.Split(output.String(), "\n")
for len(lines) > 0 && strings.HasPrefix(lines[0], "#") {
lines = lines[1:]
}
// Ditch trailing empty last line
if lines[len(lines)-1] == "" {
lines = lines[:len(lines)-1]
}
header := lines[0]
if strings.HasSuffix(header, ",") {
header = header[:len(header)-1]
}
names := strings.Split(header, "|")
tc.name = names[0]
names = names[1:]
if len(names) > 0 {
tc.desc = names[len(names)-1]
names = names[:len(names)-1]
}
tc.aliases = names
for _, val := range lines[1:] {
if (!strings.HasPrefix(val, "\t")) ||
(!strings.HasSuffix(val, ",")) {
return (errors.New("malformed infocmp: " + val))
}
val = val[1:]
val = val[:len(val)-1]
if k := strings.SplitN(val, "=", 2); len(k) == 2 {
tc.strs[k[0]] = unescape(k[1])
} else if k := strings.SplitN(val, "#", 2); len(k) == 2 {
u, err := strconv.ParseUint(k[1], 0, 0)
if err != nil {
return (err)
}
tc.nums[k[0]] = int(u)
} else {
tc.bools[val] = true
}
}
return nil
}
// LoadTerminfo creates a Terminfo by for named terminal by attempting to parse
// the output from infocmp. This returns the terminfo entry, a description of
// the terminal, and either nil or an error.
func LoadTerminfo(name string) (*terminfo.Terminfo, string, error) {
var tc termcap
if err := tc.setupterm(name); err != nil {
if err != nil {
return nil, "", err
}
}
t := &terminfo.Terminfo{}
// If this is an alias record, then just emit the alias
t.Name = tc.name
if t.Name != name {
return t, "", nil
}
t.Aliases = tc.aliases
t.Colors = tc.getnum("colors")
t.Columns = tc.getnum("cols")
t.Lines = tc.getnum("lines")
t.Bell = tc.getstr("bel")
t.Clear = tc.getstr("clear")
t.EnterCA = tc.getstr("smcup")
t.ExitCA = tc.getstr("rmcup")
t.ShowCursor = tc.getstr("cnorm")
t.HideCursor = tc.getstr("civis")
t.AttrOff = tc.getstr("sgr0")
t.Underline = tc.getstr("smul")
t.Bold = tc.getstr("bold")
t.Blink = tc.getstr("blink")
t.Dim = tc.getstr("dim")
t.Italic = tc.getstr("sitm")
t.Reverse = tc.getstr("rev")
t.EnterKeypad = tc.getstr("smkx")
t.ExitKeypad = tc.getstr("rmkx")
t.SetFg = tc.getstr("setaf")
t.SetBg = tc.getstr("setab")
t.SetCursor = tc.getstr("cup")
t.CursorBack1 = tc.getstr("cub1")
t.CursorUp1 = tc.getstr("cuu1")
t.KeyF1 = tc.getstr("kf1")
t.KeyF2 = tc.getstr("kf2")
t.KeyF3 = tc.getstr("kf3")
t.KeyF4 = tc.getstr("kf4")
t.KeyF5 = tc.getstr("kf5")
t.KeyF6 = tc.getstr("kf6")
t.KeyF7 = tc.getstr("kf7")
t.KeyF8 = tc.getstr("kf8")
t.KeyF9 = tc.getstr("kf9")
t.KeyF10 = tc.getstr("kf10")
t.KeyF11 = tc.getstr("kf11")
t.KeyF12 = tc.getstr("kf12")
t.KeyF13 = tc.getstr("kf13")
t.KeyF14 = tc.getstr("kf14")
t.KeyF15 = tc.getstr("kf15")
t.KeyF16 = tc.getstr("kf16")
t.KeyF17 = tc.getstr("kf17")
t.KeyF18 = tc.getstr("kf18")
t.KeyF19 = tc.getstr("kf19")
t.KeyF20 = tc.getstr("kf20")
t.KeyF21 = tc.getstr("kf21")
t.KeyF22 = tc.getstr("kf22")
t.KeyF23 = tc.getstr("kf23")
t.KeyF24 = tc.getstr("kf24")
t.KeyF25 = tc.getstr("kf25")
t.KeyF26 = tc.getstr("kf26")
t.KeyF27 = tc.getstr("kf27")
t.KeyF28 = tc.getstr("kf28")
t.KeyF29 = tc.getstr("kf29")
t.KeyF30 = tc.getstr("kf30")
t.KeyF31 = tc.getstr("kf31")
t.KeyF32 = tc.getstr("kf32")
t.KeyF33 = tc.getstr("kf33")
t.KeyF34 = tc.getstr("kf34")
t.KeyF35 = tc.getstr("kf35")
t.KeyF36 = tc.getstr("kf36")
t.KeyF37 = tc.getstr("kf37")
t.KeyF38 = tc.getstr("kf38")
t.KeyF39 = tc.getstr("kf39")
t.KeyF40 = tc.getstr("kf40")
t.KeyF41 = tc.getstr("kf41")
t.KeyF42 = tc.getstr("kf42")
t.KeyF43 = tc.getstr("kf43")
t.KeyF44 = tc.getstr("kf44")
t.KeyF45 = tc.getstr("kf45")
t.KeyF46 = tc.getstr("kf46")
t.KeyF47 = tc.getstr("kf47")
t.KeyF48 = tc.getstr("kf48")
t.KeyF49 = tc.getstr("kf49")
t.KeyF50 = tc.getstr("kf50")
t.KeyF51 = tc.getstr("kf51")
t.KeyF52 = tc.getstr("kf52")
t.KeyF53 = tc.getstr("kf53")
t.KeyF54 = tc.getstr("kf54")
t.KeyF55 = tc.getstr("kf55")
t.KeyF56 = tc.getstr("kf56")
t.KeyF57 = tc.getstr("kf57")
t.KeyF58 = tc.getstr("kf58")
t.KeyF59 = tc.getstr("kf59")
t.KeyF60 = tc.getstr("kf60")
t.KeyF61 = tc.getstr("kf61")
t.KeyF62 = tc.getstr("kf62")
t.KeyF63 = tc.getstr("kf63")
t.KeyF64 = tc.getstr("kf64")
t.KeyInsert = tc.getstr("kich1")
t.KeyDelete = tc.getstr("kdch1")
t.KeyBackspace = tc.getstr("kbs")
t.KeyHome = tc.getstr("khome")
t.KeyEnd = tc.getstr("kend")
t.KeyUp = tc.getstr("kcuu1")
t.KeyDown = tc.getstr("kcud1")
t.KeyRight = tc.getstr("kcuf1")
t.KeyLeft = tc.getstr("kcub1")
t.KeyPgDn = tc.getstr("knp")
t.KeyPgUp = tc.getstr("kpp")
t.KeyBacktab = tc.getstr("kcbt")
t.KeyExit = tc.getstr("kext")
t.KeyCancel = tc.getstr("kcan")
t.KeyPrint = tc.getstr("kprt")
t.KeyHelp = tc.getstr("khlp")
t.KeyClear = tc.getstr("kclr")
t.AltChars = tc.getstr("acsc")
t.EnterAcs = tc.getstr("smacs")
t.ExitAcs = tc.getstr("rmacs")
t.EnableAcs = tc.getstr("enacs")
t.Mouse = tc.getstr("kmous")
t.KeyShfRight = tc.getstr("kRIT")
t.KeyShfLeft = tc.getstr("kLFT")
t.KeyShfHome = tc.getstr("kHOM")
t.KeyShfEnd = tc.getstr("kEND")
// Terminfo lacks descriptions for a bunch of modified keys,
// but modern XTerm and emulators often have them. Let's add them,
// if the shifted right and left arrows are defined.
if t.KeyShfRight == "\x1b[1;2C" && t.KeyShfLeft == "\x1b[1;2D" {
t.KeyShfUp = "\x1b[1;2A"
t.KeyShfDown = "\x1b[1;2B"
t.KeyMetaUp = "\x1b[1;9A"
t.KeyMetaDown = "\x1b[1;9B"
t.KeyMetaRight = "\x1b[1;9C"
t.KeyMetaLeft = "\x1b[1;9D"
t.KeyAltUp = "\x1b[1;3A"
t.KeyAltDown = "\x1b[1;3B"
t.KeyAltRight = "\x1b[1;3C"
t.KeyAltLeft = "\x1b[1;3D"
t.KeyCtrlUp = "\x1b[1;5A"
t.KeyCtrlDown = "\x1b[1;5B"
t.KeyCtrlRight = "\x1b[1;5C"
t.KeyCtrlLeft = "\x1b[1;5D"
t.KeyAltShfUp = "\x1b[1;4A"
t.KeyAltShfDown = "\x1b[1;4B"
t.KeyAltShfRight = "\x1b[1;4C"
t.KeyAltShfLeft = "\x1b[1;4D"
t.KeyMetaShfUp = "\x1b[1;10A"
t.KeyMetaShfDown = "\x1b[1;10B"
t.KeyMetaShfRight = "\x1b[1;10C"
t.KeyMetaShfLeft = "\x1b[1;10D"
t.KeyCtrlShfUp = "\x1b[1;6A"
t.KeyCtrlShfDown = "\x1b[1;6B"
t.KeyCtrlShfRight = "\x1b[1;6C"
t.KeyCtrlShfLeft = "\x1b[1;6D"
t.KeyShfPgUp = "\x1b[5;2~"
t.KeyShfPgDn = "\x1b[6;2~"
}
// And also for Home and End
if t.KeyShfHome == "\x1b[1;2H" && t.KeyShfEnd == "\x1b[1;2F" {
t.KeyCtrlHome = "\x1b[1;5H"
t.KeyCtrlEnd = "\x1b[1;5F"
t.KeyAltHome = "\x1b[1;9H"
t.KeyAltEnd = "\x1b[1;9F"
t.KeyCtrlShfHome = "\x1b[1;6H"
t.KeyCtrlShfEnd = "\x1b[1;6F"
t.KeyAltShfHome = "\x1b[1;4H"
t.KeyAltShfEnd = "\x1b[1;4F"
t.KeyMetaShfHome = "\x1b[1;10H"
t.KeyMetaShfEnd = "\x1b[1;10F"
}
// And the same thing for rxvt and workalikes (Eterm, aterm, etc.)
// It seems that urxvt at least send escaped as ALT prefix for these,
// although some places seem to indicate a separate ALT key sesquence.
if t.KeyShfRight == "\x1b[c" && t.KeyShfLeft == "\x1b[d" {
t.KeyShfUp = "\x1b[a"
t.KeyShfDown = "\x1b[b"
t.KeyCtrlUp = "\x1b[Oa"
t.KeyCtrlDown = "\x1b[Ob"
t.KeyCtrlRight = "\x1b[Oc"
t.KeyCtrlLeft = "\x1b[Od"
}
if t.KeyShfHome == "\x1b[7$" && t.KeyShfEnd == "\x1b[8$" {
t.KeyCtrlHome = "\x1b[7^"
t.KeyCtrlEnd = "\x1b[8^"
}
// Technically the RGB flag that is provided for xterm-direct is not
// quite right. The problem is that the -direct flag that was introduced
// with ncurses 6.1 requires a parsing for the parameters that we lack.
// For this case we'll just assume it's XTerm compatible. Someday this
// may be incorrect, but right now it is correct, and nobody uses it
// anyway.
if tc.getflag("Tc") {
// This presumes XTerm 24-bit true color.
t.TrueColor = true
} else if tc.getflag("RGB") {
// This is for xterm-direct, which uses a different scheme entirely.
// (ncurses went a very different direction from everyone else, and
// so it's unlikely anything is using this definition.)
t.TrueColor = true
t.SetBg = "\x1b[%?%p1%{8}%<%t4%p1%d%e%p1%{16}%<%t10%p1%{8}%-%d%e48;5;%p1%d%;m"
t.SetFg = "\x1b[%?%p1%{8}%<%t3%p1%d%e%p1%{16}%<%t9%p1%{8}%-%d%e38;5;%p1%d%;m"
}
// We only support colors in ANSI 8 or 256 color mode.
if t.Colors < 8 || t.SetFg == "" {
t.Colors = 0
}
if t.SetCursor == "" {
return nil, "", errNotAddressable
}
// For padding, we lookup the pad char. If that isn't present,
// and npc is *not* set, then we assume a null byte.
t.PadChar = tc.getstr("pad")
if t.PadChar == "" {
if !tc.getflag("npc") {
t.PadChar = "\u0000"
}
}
// For terminals that use "standard" SGR sequences, lets combine the
// foreground and background together.
if strings.HasPrefix(t.SetFg, "\x1b[") &&
strings.HasPrefix(t.SetBg, "\x1b[") &&
strings.HasSuffix(t.SetFg, "m") &&
strings.HasSuffix(t.SetBg, "m") {
fg := t.SetFg[:len(t.SetFg)-1]
r := regexp.MustCompile("%p1")
bg := r.ReplaceAllString(t.SetBg[2:], "%p2")
t.SetFgBg = fg + ";" + bg
}
return t, tc.desc, nil
}