vendor: github.com/nsf/termbox-go and dependencies for rclone ncdu

vendor/github.com/nsf/termbox-go/terminfo.go

@@ -0,0 +1,221 @@
+// +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,
+}