315 lines
6.7 KiB
Go
315 lines
6.7 KiB
Go
package gapstring
|
||
|
||
import (
|
||
"fmt"
|
||
"encoding/binary"
|
||
"encoding/hex"
|
||
"strings"
|
||
"unicode/utf16"
|
||
)
|
||
|
||
// XXX: I think there's a clever way to do this with interfaces
|
||
// XXX: But I'm too exhausted to figure it out.
|
||
// XXX: I'll have to fix it later; it doesn't matter much for performance
|
||
|
||
type chunk struct {
|
||
gap int // This takes precedence over data
|
||
data []byte
|
||
}
|
||
|
||
func (c chunk) length() int {
|
||
if c.gap > 0 {
|
||
return c.gap
|
||
} else {
|
||
return len(c.data)
|
||
}
|
||
}
|
||
|
||
func (c chunk) missing() int {
|
||
return c.gap
|
||
}
|
||
|
||
func (c chunk) slice(a, b int) chunk {
|
||
if b > c.length() {
|
||
panic("runtime error: index out of range")
|
||
}
|
||
if c.gap > 0 {
|
||
return chunk{gap: b - a}
|
||
} else {
|
||
return chunk{data: c.data[a:b]}
|
||
}
|
||
}
|
||
|
||
|
||
type GapString struct {
|
||
chunks []chunk
|
||
}
|
||
|
||
func New() GapString {
|
||
return GapString{
|
||
chunks: []chunk{},
|
||
}
|
||
}
|
||
|
||
func OfGap(gap int) GapString {
|
||
return GapString{
|
||
chunks: []chunk{{gap: gap}},
|
||
}
|
||
}
|
||
|
||
func OfBytes(b []byte) GapString {
|
||
return GapString{
|
||
chunks: []chunk{{data: b}},
|
||
}
|
||
}
|
||
|
||
func OfString(s string) GapString {
|
||
return OfBytes([]byte(s))
|
||
}
|
||
|
||
func (g GapString) Length() int {
|
||
n := 0
|
||
for _, c := range g.chunks {
|
||
n += c.length()
|
||
}
|
||
return n
|
||
}
|
||
|
||
func (g GapString) Missing() int {
|
||
n := 0
|
||
for _, c := range g.chunks {
|
||
n += c.missing()
|
||
}
|
||
return n
|
||
}
|
||
|
||
func (g GapString) Append(h GapString) GapString {
|
||
if h.Length() > 0 {
|
||
return GapString{
|
||
chunks: append(g.chunks, h.chunks...),
|
||
}
|
||
} else {
|
||
return g
|
||
}
|
||
}
|
||
|
||
func (g GapString) AppendGap(gap int) GapString {
|
||
return g.Append(OfGap(gap))
|
||
}
|
||
|
||
func (g GapString) AppendBytes(b []byte) GapString {
|
||
return g.Append(OfBytes(b))
|
||
}
|
||
|
||
func (g GapString) AppendString(s string) GapString {
|
||
return g.Append(OfString(s))
|
||
}
|
||
|
||
func (g GapString) Slice(start, end int) GapString {
|
||
outchunks := make([]chunk, 0, len(g.chunks))
|
||
|
||
if end > g.Length() {
|
||
panic("runtime error: slice bounds out of range")
|
||
}
|
||
|
||
for _, c := range g.chunks {
|
||
chunklen := c.length()
|
||
|
||
// Discard chunks that appear before the first
|
||
if start > chunklen {
|
||
start -= chunklen
|
||
end -= chunklen
|
||
continue
|
||
}
|
||
|
||
// Append chunks until we're done
|
||
cend := chunklen
|
||
if cend > end {
|
||
cend = end
|
||
}
|
||
if start != cend {
|
||
outchunks = append(outchunks, c.slice(start, cend))
|
||
}
|
||
start = 0
|
||
end -= cend
|
||
|
||
if end == 0 {
|
||
break
|
||
}
|
||
}
|
||
|
||
return GapString{chunks: outchunks}
|
||
}
|
||
|
||
func (g GapString) Xor(mask ...byte) GapString {
|
||
ret := GapString{}
|
||
pos := 0
|
||
for _, c := range g.chunks {
|
||
ret = ret.AppendGap(c.gap)
|
||
|
||
out := make([]byte, len(c.data))
|
||
for i, b := range c.data {
|
||
m := mask[(pos+i)%len(mask)]
|
||
out[i] = b ^ m
|
||
}
|
||
ret = ret.AppendBytes(out)
|
||
|
||
pos += c.length()
|
||
}
|
||
return ret
|
||
}
|
||
|
||
func (g GapString) Bytes(fill ...byte) []byte {
|
||
ret := make([]byte, g.Length())
|
||
pos := 0
|
||
for _, c := range g.chunks {
|
||
// Fill in gap
|
||
if len(fill) > 0 {
|
||
for i := 0; i < c.gap; i += 1 {
|
||
ret[pos] = fill[pos % len(fill)]
|
||
pos += 1
|
||
}
|
||
}
|
||
// Fill in bytes
|
||
for _, b := range c.data {
|
||
ret[pos] = b
|
||
pos += 1
|
||
}
|
||
}
|
||
ret = ret[0:pos]
|
||
return ret
|
||
}
|
||
|
||
// Returns -1 if it's a gap
|
||
func (g GapString) ValueAt(pos int) int {
|
||
v := g.Slice(pos, pos+1)
|
||
if v.chunks[0].gap > 0 {
|
||
return -1
|
||
} else {
|
||
return int(v.chunks[0].data[0])
|
||
}
|
||
}
|
||
|
||
func (g GapString) String(fill string) string {
|
||
return string(g.Bytes([]byte(fill)...))
|
||
}
|
||
|
||
func (g GapString) HexString(fill ...byte) string {
|
||
return hex.EncodeToString(g.Bytes(fill...))
|
||
}
|
||
|
||
var fluffych = []rune{
|
||
'·', '☺', '☻', '♥', '♦', '♣', '♠', '•', '◘', '○', '◙', '♂', '♀', '♪', '♫', '☼',
|
||
'►', '◄', '↕', '‼', '¶', '§', '▬', '↨', '↑', '↓', '→', '←', '∟', '↔', '▲', '▼',
|
||
' ', '!', '"', '#', '$', '%', '&', '\'', '(', ')', '*', '+', ',', '-', '.', '/',
|
||
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', ':', ';', '<', '=', '>', '?',
|
||
'@', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
|
||
'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '[', '\\', ']', '^', '_',
|
||
'`', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o',
|
||
'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '{', '|', '}', '~', '⌂',
|
||
'Ç', 'ü', 'é', 'â', 'ä', 'à', 'å', 'ç', 'ê', 'ë', 'è', 'ï', 'î', 'ì', 'Ä', 'Å',
|
||
'É', 'æ', 'Æ', 'ô', 'ö', 'ò', 'û', 'ù', 'ÿ', 'Ö', 'Ü', '¢', '£', '¥', '₧', 'ƒ',
|
||
'á', 'í', 'ó', 'ú', 'ñ', 'Ñ', 'ª', 'º', '¿', '⌐', '¬', '½', '¼', '¡', '«', '»',
|
||
'░', '▒', '▓', '│', '┤', '╡', '╢', '╖', '╕', '╣', '║', '╗', '╝', '╜', '╛', '┐',
|
||
'└', '┴', '┬', '├', '─', '┼', '╞', '╟', '╚', '╔', '╩', '╦', '╠', '═', '╬', '╧',
|
||
'╨', '╤', '╥', '╙', '╘', '╒', '╓', '╫', '╪', '┘', '┌', '█', '▄', '▌', '▐', '▀',
|
||
'α', 'ß', 'Γ', 'π', 'Σ', 'σ', 'µ', 'τ', 'Φ', 'Θ', 'Ω', 'δ', '∞', 'φ', 'ε', '∩',
|
||
'≡', '±', '≥', '≤', '⌠', '⌡', '÷', '≈', '°', '∀', '∃', '√', 'ⁿ', '²', '■', '¤',
|
||
}
|
||
func (g GapString) Hexdump() string {
|
||
out := new(strings.Builder)
|
||
skipping := false
|
||
glen := g.Length()
|
||
pos := 0
|
||
for ; pos < glen; {
|
||
// Check for repeats
|
||
repeated := true
|
||
if (pos > 0) {
|
||
for i := 0; (i < 16) && (pos+i < glen); i += 1 {
|
||
if g.ValueAt(pos+i) != g.ValueAt(pos+i-16) {
|
||
repeated = false
|
||
break
|
||
}
|
||
}
|
||
if repeated {
|
||
if ! skipping {
|
||
fmt.Fprintln(out, "*")
|
||
skipping = true
|
||
}
|
||
pos += 16
|
||
continue
|
||
} else {
|
||
skipping = false
|
||
}
|
||
}
|
||
|
||
// Output offset
|
||
fmt.Fprintf(out, "%08x ", pos)
|
||
|
||
// Output octet values
|
||
for i := 0; i < 16; i += 1 {
|
||
if pos+i < glen {
|
||
c := g.ValueAt(pos+i)
|
||
if c == -1 {
|
||
fmt.Fprintf(out, "-- ")
|
||
} else {
|
||
fmt.Fprintf(out, "%02x ", c)
|
||
}
|
||
} else {
|
||
fmt.Fprintf(out, " ")
|
||
}
|
||
if i == 7 {
|
||
fmt.Fprintf(out, " ")
|
||
}
|
||
}
|
||
|
||
fmt.Fprintf(out, " ")
|
||
|
||
|
||
// Output octet glyphs
|
||
for i := 0; (i < 16) && (pos < glen); {
|
||
c := g.ValueAt(pos)
|
||
if c == -1 {
|
||
fmt.Fprintf(out, "<22>")
|
||
} else {
|
||
fmt.Fprintf(out, "%c", fluffych[c])
|
||
}
|
||
i += 1
|
||
pos += 1
|
||
}
|
||
|
||
// Output newline
|
||
fmt.Fprintln(out, "")
|
||
}
|
||
fmt.Fprintf(out, "%08x\n", pos)
|
||
|
||
return out.String()
|
||
}
|
||
|
||
func (g GapString) Uint32LE() (uint32, GapString) {
|
||
return binary.LittleEndian.Uint32(g.Slice(0, 4).Bytes()), g.Slice(4, g.Length())
|
||
}
|
||
|
||
func (g GapString) Uint16LE() (uint16, GapString) {
|
||
return binary.LittleEndian.Uint16(g.Slice(0, 2).Bytes()), g.Slice(2, g.Length())
|
||
}
|
||
|
||
func (g GapString) Utf16(o binary.ByteOrder, fill string) string {
|
||
in := g.Bytes([]byte(fill)...)
|
||
ints := make([]uint16, len(in)/2)
|
||
|
||
for i := 0; i < len(in); i += 2 {
|
||
ints[i/2] = o.Uint16(in[i:])
|
||
}
|
||
return string(utf16.Decode(ints))
|
||
}
|
||
|
||
func (g GapString) Utf16LE(gap string) string {
|
||
return g.Utf16(binary.LittleEndian, gap)
|
||
}
|
||
|
||
func (g GapString) Utf16BE(gap string) string {
|
||
return g.Utf16(binary.BigEndian, gap)
|
||
}
|
||
|