piframe-go/vendor/github.com/eiannone/keyboard/terminfo.go
2020-08-29 19:11:30 -04:00

258 lines
6.8 KiB
Go

// +build !windows
// This file is imported from https://github.com/nsf/termbox-go
// Last update: 2020-04-30
// This file contains a simple and incomplete implementation of the terminfo
// database. Information was taken from the ncurses manpages term(5) and
// terminfo(5). Currently, only the string capabilities for special keys and for
// functions without parameters are actually used. Colors are still done with
// ANSI escape sequences. Other special features that are not (yet?) supported
// are reading from ~/.terminfo, the TERMINFO_DIRS variable, Berkeley database
// format and extended capabilities.
package keyboard
import (
"bytes"
"encoding/binary"
"encoding/hex"
"errors"
"io/ioutil"
"os"
"strings"
)
const (
ti_header_length = 12
)
var (
eterm_keys = []string{
"\x1b[11~", "\x1b[12~", "\x1b[13~", "\x1b[14~", "\x1b[15~", "\x1b[17~", "\x1b[18~", "\x1b[19~", "\x1b[20~", "\x1b[21~", "\x1b[23~", "\x1b[24~", "\x1b[2~", "\x1b[3~", "\x1b[7~", "\x1b[8~", "\x1b[5~", "\x1b[6~", "\x1b[A", "\x1b[B", "\x1b[D", "\x1b[C",
}
screen_keys = []string{
"\x1bOP", "\x1bOQ", "\x1bOR", "\x1bOS", "\x1b[15~", "\x1b[17~", "\x1b[18~", "\x1b[19~", "\x1b[20~", "\x1b[21~", "\x1b[23~", "\x1b[24~", "\x1b[2~", "\x1b[3~", "\x1b[1~", "\x1b[4~", "\x1b[5~", "\x1b[6~", "\x1bOA", "\x1bOB", "\x1bOD", "\x1bOC",
}
xterm_keys = []string{
"\x1bOP", "\x1bOQ", "\x1bOR", "\x1bOS", "\x1b[15~", "\x1b[17~", "\x1b[18~", "\x1b[19~", "\x1b[20~", "\x1b[21~", "\x1b[23~", "\x1b[24~", "\x1b[2~", "\x1b[3~", "\x1b[H", "\x1b[F", "\x1b[5~", "\x1b[6~", "\x1b[A", "\x1b[B", "\x1b[D", "\x1b[C",
}
rxvt_keys = []string{
"\x1b[11~", "\x1b[12~", "\x1b[13~", "\x1b[14~", "\x1b[15~", "\x1b[17~", "\x1b[18~", "\x1b[19~", "\x1b[20~", "\x1b[21~", "\x1b[23~", "\x1b[24~", "\x1b[2~", "\x1b[3~", "\x1b[7~", "\x1b[8~", "\x1b[5~", "\x1b[6~", "\x1b[A", "\x1b[B", "\x1b[D", "\x1b[C",
}
linux_keys = []string{
"\x1b[[A", "\x1b[[B", "\x1b[[C", "\x1b[[D", "\x1b[[E", "\x1b[17~", "\x1b[18~", "\x1b[19~", "\x1b[20~", "\x1b[21~", "\x1b[23~", "\x1b[24~", "\x1b[2~", "\x1b[3~", "\x1b[1~", "\x1b[4~", "\x1b[5~", "\x1b[6~", "\x1b[A", "\x1b[B", "\x1b[D", "\x1b[C",
}
terms = []struct {
name string
keys []string
}{
{"Eterm", eterm_keys},
{"screen", screen_keys},
{"xterm", xterm_keys},
{"xterm-256color", xterm_keys},
{"rxvt-unicode", rxvt_keys},
{"rxvt-256color", rxvt_keys},
{"linux", linux_keys},
}
)
func load_terminfo() ([]byte, error) {
var data []byte
var err error
term := os.Getenv("TERM")
if term == "" {
return nil, errors.New("terminfo: TERM not set")
}
// Check if is a builtin terminal
for _, t := range terms {
if t.name == term {
return nil, errors.New("use built in!")
}
}
// The following behaviour follows the one described in terminfo(5) as
// distributed by ncurses.
terminfo := os.Getenv("TERMINFO")
if terminfo != "" {
// if TERMINFO is set, no other directory should be searched
return ti_try_path(terminfo)
}
// next, consider ~/.terminfo
home := os.Getenv("HOME")
if home != "" {
data, err = ti_try_path(home + "/.terminfo")
if err == nil {
return data, nil
}
}
// next, TERMINFO_DIRS
dirs := os.Getenv("TERMINFO_DIRS")
if dirs != "" {
for _, dir := range strings.Split(dirs, ":") {
if dir == "" {
// "" -> "/usr/share/terminfo"
dir = "/usr/share/terminfo"
}
data, err = ti_try_path(dir)
if err == nil {
return data, nil
}
}
}
// next, /lib/terminfo
data, err = ti_try_path("/lib/terminfo")
if err == nil {
return data, nil
}
// fall back to /usr/share/terminfo
return ti_try_path("/usr/share/terminfo")
}
func ti_try_path(path string) (data []byte, err error) {
// load_terminfo already made sure it is set
term := os.Getenv("TERM")
// first try, the typical *nix path
terminfo := path + "/" + term[0:1] + "/" + term
data, err = ioutil.ReadFile(terminfo)
if err == nil {
return
}
// fallback to darwin specific dirs structure
terminfo = path + "/" + hex.EncodeToString([]byte(term[:1])) + "/" + term
data, err = ioutil.ReadFile(terminfo)
return
}
func setup_term_builtin() error {
name := os.Getenv("TERM")
if name == "" {
return errors.New("terminfo: TERM environment variable not set")
}
for _, t := range terms {
if t.name == name {
keys = t.keys
return nil
}
}
compat_table := []struct {
partial string
keys []string
}{
{"xterm", xterm_keys},
{"xterm-256color", xterm_keys},
{"rxvt", rxvt_keys},
{"rxvt-unicode", rxvt_keys},
{"rxvt-256color", rxvt_keys},
{"linux", linux_keys},
{"Eterm", eterm_keys},
{"screen", screen_keys},
// let's assume that 'cygwin' is xterm compatible
{"cygwin", xterm_keys},
{"st", xterm_keys},
}
// try compatibility variants
for _, it := range compat_table {
if strings.Contains(name, it.partial) {
keys = it.keys
return nil
}
}
return errors.New("termbox: unsupported terminal")
}
func setup_term() (err error) {
var data []byte
var header [6]int16
var str_offset, table_offset int16
data, err = load_terminfo()
if err != nil {
return setup_term_builtin()
}
rd := bytes.NewReader(data)
// 0: magic number, 1: size of names section, 2: size of boolean section, 3:
// size of numbers section (in integers), 4: size of the strings section (in
// integers), 5: size of the string table
err = binary.Read(rd, binary.LittleEndian, header[:])
if err != nil {
return
}
if header[0] != 542 && header[0] != 282 {
return setup_term_builtin()
}
number_sec_len := int16(2)
if header[0] == 542 { // doc says it should be octal 0542, but what I see it terminfo files is 542, learn to program please... thank you..
number_sec_len = 4
}
if (header[1]+header[2])%2 != 0 {
// old quirk to align everything on word boundaries
header[2] += 1
}
str_offset = ti_header_length + header[1] + header[2] + number_sec_len*header[3]
table_offset = str_offset + 2*header[4]
keys = make([]string, 0xFFFF-key_min)
for i := range keys {
keys[i], err = ti_read_string(rd, str_offset+2*ti_keys[i], table_offset)
if err != nil {
return
}
}
return nil
}
func ti_read_string(rd *bytes.Reader, str_off, table int16) (string, error) {
var off int16
_, err := rd.Seek(int64(str_off), 0)
if err != nil {
return "", err
}
err = binary.Read(rd, binary.LittleEndian, &off)
if err != nil {
return "", err
}
_, err = rd.Seek(int64(table+off), 0)
if err != nil {
return "", err
}
var bs []byte
for {
b, err := rd.ReadByte()
if err != nil {
return "", err
}
if b == byte(0x00) {
break
}
bs = append(bs, b)
}
return string(bs), nil
}
// "Maps" special keys constants from termbox.go to the number of the respective
// string capability in the terminfo file. Taken from (ncurses) term.h.
var ti_keys = []int16{
66, 68 /* apparently not a typo; 67 is F10 for whatever reason */, 69, 70,
71, 72, 73, 74, 75, 67, 216, 217, 77, 59, 76, 164, 82, 81, 87, 61, 79, 83,
}