// +build !windows
// 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 termbox
import (
"bytes"
"encoding/binary"
"encoding/hex"
"errors"
"fmt"
"io/ioutil"
"os"
"strings"
)
const (
ti_magic = 0432
ti_header_length = 12
ti_mouse_enter = "\x1b[?1000h\x1b[?1002h\x1b[?1015h\x1b[?1006h"
ti_mouse_leave = "\x1b[?1006l\x1b[?1015l\x1b[?1002l\x1b[?1000l"
)
func load_terminfo() ([]byte, error) {
var data []byte
var err error
term := os.Getenv("TERM")
if term == "" {
return nil, fmt.Errorf("termbox: TERM not set")
}
// 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
}
}
}
// 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("termbox: TERM environment variable not set")
}
for _, t := range terms {
if t.name == name {
keys = t.keys
funcs = t.funcs
return nil
}
}
compat_table := []struct {
partial string
keys []string
funcs []string
}{
{"xterm", xterm_keys, xterm_funcs},
{"rxvt", rxvt_unicode_keys, rxvt_unicode_funcs},
{"linux", linux_keys, linux_funcs},
{"Eterm", eterm_keys, eterm_funcs},
{"screen", screen_keys, screen_funcs},
// let's assume that 'cygwin' is xterm compatible
{"cygwin", xterm_keys, xterm_funcs},
{"st", xterm_keys, xterm_funcs},
}
// try compatibility variants
for _, it := range compat_table {
if strings.Contains(name, it.partial) {
keys = it.keys
funcs = it.funcs
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[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] + 2*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
}
}
funcs = make([]string, t_max_funcs)
// the last two entries are reserved for mouse. because the table offset is
// not there, the two entries have to fill in manually
for i, _ := range funcs[:len(funcs)-2] {
funcs[i], err = ti_read_string(rd, str_offset+2*ti_funcs[i], table_offset)
if err != nil {
return
}
}
funcs[t_max_funcs-2] = ti_mouse_enter
funcs[t_max_funcs-1] = ti_mouse_leave
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" the function constants from termbox.go to the number of the respective
// string capability in the terminfo file. Taken from (ncurses) term.h.
var ti_funcs = []int16{
28, 40, 16, 13, 5, 39, 36, 27, 26, 34, 89, 88,
}
// Same as above for the special keys.
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,
}
