mirror of
https://github.com/thead-yocto-mirror/skia
synced 2026-09-16 20:22:06 +02:00
1094 lines
25 KiB
Go
1094 lines
25 KiB
Go
// Copyright 2018 The Wuffs Authors.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// https://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.
|
|
|
|
// +build ignore
|
|
|
|
package main
|
|
|
|
// make-artificial.go makes test data in various formats.
|
|
//
|
|
// See test/data/artificial/*.make.txt for examples.
|
|
//
|
|
// Usage: go run make-artificial.go < foo.make.txt
|
|
|
|
import (
|
|
"bytes"
|
|
"compress/lzw"
|
|
"fmt"
|
|
"io/ioutil"
|
|
"os"
|
|
"strconv"
|
|
"strings"
|
|
)
|
|
|
|
type stateFunc func(line string) (stateFunc, error)
|
|
|
|
type repeat struct {
|
|
count uint32
|
|
remaining string
|
|
}
|
|
|
|
var (
|
|
state stateFunc
|
|
repeats []repeat
|
|
out []byte
|
|
formats = map[string]stateFunc{}
|
|
)
|
|
|
|
func main() {
|
|
if err := main1(); err != nil {
|
|
os.Stderr.WriteString(err.Error() + "\n")
|
|
os.Exit(1)
|
|
}
|
|
}
|
|
|
|
func main1() error {
|
|
stdin, err := ioutil.ReadAll(os.Stdin)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
s := string(stdin)
|
|
for remaining := ""; len(s) > 0; s, remaining = remaining, "" {
|
|
if i := strings.IndexByte(s, '\n'); i >= 0 {
|
|
s, remaining = s[:i], s[i+1:]
|
|
}
|
|
s = strings.TrimSpace(s)
|
|
if s == "" || s[0] == '#' {
|
|
continue
|
|
}
|
|
|
|
if state == nil {
|
|
const m = "make "
|
|
if !strings.HasPrefix(s, m) {
|
|
return fmt.Errorf(`input must start with "make foo"`)
|
|
}
|
|
s = s[len(m):]
|
|
state = formats[s]
|
|
if state == nil {
|
|
return fmt.Errorf("unsupported format %q", s)
|
|
}
|
|
continue
|
|
}
|
|
|
|
const rep = "repeat "
|
|
if strings.HasPrefix(s, rep) {
|
|
args := s[len(rep):]
|
|
count, args, ok := parseNum(args)
|
|
if !ok || count <= 0 || args != "[" {
|
|
return fmt.Errorf("bad repeat command: %q", s)
|
|
}
|
|
repeats = append(repeats, repeat{
|
|
count: count,
|
|
remaining: remaining,
|
|
})
|
|
continue
|
|
}
|
|
|
|
if s == "]" {
|
|
if len(repeats) <= 0 {
|
|
return fmt.Errorf(`unbalanced close-repeat command: "]"`)
|
|
}
|
|
i := len(repeats) - 1
|
|
repeats[i].count--
|
|
if repeats[i].count == 0 {
|
|
repeats = repeats[:i]
|
|
} else {
|
|
remaining = repeats[i].remaining
|
|
}
|
|
continue
|
|
}
|
|
|
|
state, err = state(s)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
if state == nil {
|
|
return fmt.Errorf("bad state transition")
|
|
}
|
|
}
|
|
|
|
if state == nil {
|
|
return fmt.Errorf("no 'make' line")
|
|
} else {
|
|
state, err = state("")
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
_, err = os.Stdout.Write(out)
|
|
return err
|
|
}
|
|
|
|
// ----
|
|
|
|
func appendU16LE(b []byte, u uint16) []byte {
|
|
return append(b, uint8(u), uint8(u>>8))
|
|
}
|
|
|
|
func log2(u uint32) (i int32) {
|
|
for i, pow := uint32(0), uint32(1); i < 32; i, pow = i+1, pow<<1 {
|
|
if u == pow {
|
|
return int32(i)
|
|
}
|
|
if u < pow {
|
|
break
|
|
}
|
|
}
|
|
return -1
|
|
}
|
|
|
|
func parseHex(s string) (num uint32, remaining string, ok bool) {
|
|
if i := strings.IndexByte(s, ' '); i >= 0 {
|
|
s, remaining = s[:i], s[i+1:]
|
|
for len(remaining) > 0 && remaining[0] == ' ' {
|
|
remaining = remaining[1:]
|
|
}
|
|
}
|
|
|
|
if len(s) < 2 || s[0] != '0' || s[1] != 'x' {
|
|
return 0, "", false
|
|
}
|
|
s = s[2:]
|
|
|
|
u, err := strconv.ParseUint(s, 16, 32)
|
|
if err != nil {
|
|
return 0, "", false
|
|
}
|
|
return uint32(u), remaining, true
|
|
}
|
|
|
|
func parseNum(s string) (num uint32, remaining string, ok bool) {
|
|
if i := strings.IndexByte(s, ' '); i >= 0 {
|
|
s, remaining = s[:i], s[i+1:]
|
|
for len(remaining) > 0 && remaining[0] == ' ' {
|
|
remaining = remaining[1:]
|
|
}
|
|
}
|
|
|
|
u, err := strconv.ParseUint(s, 10, 32)
|
|
if err != nil {
|
|
return 0, "", false
|
|
}
|
|
return uint32(u), remaining, true
|
|
}
|
|
|
|
func reverse(x uint32, n uint32) uint32 {
|
|
x = uint32(reverse8[0xFF&(x>>0)])<<24 |
|
|
uint32(reverse8[0xFF&(x>>8)])<<16 |
|
|
uint32(reverse8[0xFF&(x>>16)])<<8 |
|
|
uint32(reverse8[0xFF&(x>>24)])<<0
|
|
return x >> (32 - n)
|
|
}
|
|
|
|
var reverse8 = [256]byte{
|
|
0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, // 0x00 - 0x07
|
|
0x10, 0x90, 0x50, 0xD0, 0x30, 0xB0, 0x70, 0xF0, // 0x08 - 0x0F
|
|
0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, // 0x10 - 0x17
|
|
0x18, 0x98, 0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, // 0x18 - 0x1F
|
|
0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64, 0xE4, // 0x20 - 0x27
|
|
0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4, // 0x28 - 0x2F
|
|
0x0C, 0x8C, 0x4C, 0xCC, 0x2C, 0xAC, 0x6C, 0xEC, // 0x30 - 0x37
|
|
0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC, // 0x38 - 0x3F
|
|
0x02, 0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, // 0x40 - 0x47
|
|
0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2, 0x72, 0xF2, // 0x48 - 0x4F
|
|
0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, // 0x50 - 0x57
|
|
0x1A, 0x9A, 0x5A, 0xDA, 0x3A, 0xBA, 0x7A, 0xFA, // 0x58 - 0x5F
|
|
0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6, // 0x60 - 0x67
|
|
0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6, // 0x68 - 0x6F
|
|
0x0E, 0x8E, 0x4E, 0xCE, 0x2E, 0xAE, 0x6E, 0xEE, // 0x70 - 0x77
|
|
0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, // 0x78 - 0x7F
|
|
0x01, 0x81, 0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, // 0x80 - 0x87
|
|
0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71, 0xF1, // 0x88 - 0x8F
|
|
0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, // 0x90 - 0x97
|
|
0x19, 0x99, 0x59, 0xD9, 0x39, 0xB9, 0x79, 0xF9, // 0x98 - 0x9F
|
|
0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, // 0xA0 - 0xA7
|
|
0x15, 0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, // 0xA8 - 0xAF
|
|
0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD, 0x6D, 0xED, // 0xB0 - 0xB7
|
|
0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD, // 0xB8 - 0xBF
|
|
0x03, 0x83, 0x43, 0xC3, 0x23, 0xA3, 0x63, 0xE3, // 0xC0 - 0xC7
|
|
0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3, // 0xC8 - 0xCF
|
|
0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, // 0xD0 - 0xD7
|
|
0x1B, 0x9B, 0x5B, 0xDB, 0x3B, 0xBB, 0x7B, 0xFB, // 0xD8 - 0xDF
|
|
0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, // 0xE0 - 0xE7
|
|
0x17, 0x97, 0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7, // 0xE8 - 0xEF
|
|
0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F, 0xEF, // 0xF0 - 0xF7
|
|
0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF, // 0xF8 - 0xFF
|
|
}
|
|
|
|
// ----
|
|
|
|
func init() {
|
|
formats["deflate"] = stateDeflate
|
|
}
|
|
|
|
var deflateCodeOrder = [19]uint32{
|
|
16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15,
|
|
}
|
|
|
|
type deflateHuffmanTable map[uint32]string
|
|
|
|
var deflateGlobals struct {
|
|
bncData []byte
|
|
stream deflateBitStream
|
|
|
|
// Dynamic Huffman state.
|
|
numLCodes uint32
|
|
numDCodes uint32
|
|
numCLCodeLengths uint32
|
|
whichHuffman uint32
|
|
// 0=Unused, 1=CodeLength, 2=Length/Literal, 3=Distance.
|
|
huffmans [4]deflateHuffmanTable
|
|
}
|
|
|
|
func deflateGlobalsClearDynamicHuffmanState() {
|
|
deflateGlobals.numLCodes = 0
|
|
deflateGlobals.numDCodes = 0
|
|
deflateGlobals.numCLCodeLengths = 0
|
|
deflateGlobals.whichHuffman = 0
|
|
deflateGlobals.huffmans = [4]deflateHuffmanTable{}
|
|
}
|
|
|
|
func deflateGlobalsWriteDynamicHuffmanTables() error {
|
|
g := &deflateGlobals
|
|
if (g.numLCodes < 257) || (257+31 < g.numLCodes) {
|
|
return fmt.Errorf("bad numLCodes: %d", g.numLCodes)
|
|
}
|
|
g.stream.writeBits(g.numLCodes-257, 5)
|
|
if (g.numDCodes < 1) || (1+31 < g.numDCodes) {
|
|
return fmt.Errorf("bad numDCodes: %d", g.numDCodes)
|
|
}
|
|
g.stream.writeBits(g.numDCodes-1, 5)
|
|
if (g.numCLCodeLengths < 4) || (4+15 < g.numCLCodeLengths) {
|
|
return fmt.Errorf("bad numCLCodeLengths: %d", g.numCLCodeLengths)
|
|
}
|
|
g.stream.writeBits(g.numCLCodeLengths-4, 4)
|
|
|
|
// Write the Huffman table for CodeLength.
|
|
{
|
|
for i := uint32(0); i < g.numCLCodeLengths; i++ {
|
|
n := len(g.huffmans[1][deflateCodeOrder[i]])
|
|
g.stream.writeBits(uint32(n), 3)
|
|
}
|
|
for i := g.numCLCodeLengths; i < uint32(len(deflateCodeOrder)); i++ {
|
|
n := len(g.huffmans[1][deflateCodeOrder[i]])
|
|
if n > 0 {
|
|
return fmt.Errorf("short numCLCodeLengths: %d", g.numCLCodeLengths)
|
|
}
|
|
}
|
|
}
|
|
|
|
// Write the Huffman tables for Length/Literal and Distance.
|
|
{
|
|
numZeroes := uint32(0)
|
|
for i := uint32(0); i < g.numLCodes+g.numDCodes; i++ {
|
|
s := ""
|
|
if i < g.numLCodes {
|
|
s = g.huffmans[2][i]
|
|
} else {
|
|
s = g.huffmans[3][i-g.numLCodes]
|
|
}
|
|
if s == "" {
|
|
numZeroes++
|
|
continue
|
|
}
|
|
|
|
if err := deflateGlobalsWriteDynamicHuffmanZeroes(numZeroes); err != nil {
|
|
return err
|
|
}
|
|
numZeroes = 0
|
|
|
|
deflateGlobalsWriteDynamicHuffmanBits(g.huffmans[1][uint32(len(s))])
|
|
}
|
|
if err := deflateGlobalsWriteDynamicHuffmanZeroes(numZeroes); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func deflateGlobalsWriteDynamicHuffmanZeroes(numZeroes uint32) error {
|
|
g := &deflateGlobals
|
|
if numZeroes == 0 {
|
|
return nil
|
|
}
|
|
|
|
if s := g.huffmans[1][18]; s != "" {
|
|
for numZeroes >= 11 {
|
|
extra := numZeroes - 11
|
|
if extra > 127 {
|
|
extra = 127
|
|
}
|
|
deflateGlobalsWriteDynamicHuffmanBits(s)
|
|
g.stream.writeBits(extra, 7)
|
|
numZeroes -= 11 + extra
|
|
}
|
|
}
|
|
|
|
if s := g.huffmans[1][17]; s != "" {
|
|
for numZeroes >= 3 {
|
|
extra := numZeroes - 3
|
|
if extra > 7 {
|
|
extra = 7
|
|
}
|
|
deflateGlobalsWriteDynamicHuffmanBits(s)
|
|
g.stream.writeBits(extra, 3)
|
|
numZeroes -= 3 + extra
|
|
}
|
|
}
|
|
|
|
if s := g.huffmans[1][0]; s != "" {
|
|
for ; numZeroes > 0; numZeroes-- {
|
|
deflateGlobalsWriteDynamicHuffmanBits(s)
|
|
}
|
|
}
|
|
|
|
if numZeroes > 0 {
|
|
return fmt.Errorf("could not write a run of zero-valued code lengths")
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func deflateGlobalsWriteDynamicHuffmanBits(s string) {
|
|
g := &deflateGlobals
|
|
for i := 0; i < len(s); i++ {
|
|
g.stream.writeBits(uint32(s[i]&1), 1)
|
|
}
|
|
}
|
|
|
|
func parseDeflateWhichHuffman(s string) (num uint32, remaining string, ok bool) {
|
|
if i := strings.IndexByte(s, ' '); i >= 0 {
|
|
s, remaining = s[:i], s[i+1:]
|
|
for len(remaining) > 0 && remaining[0] == ' ' {
|
|
remaining = remaining[1:]
|
|
}
|
|
}
|
|
|
|
switch s {
|
|
case "CodeLength":
|
|
return 1, remaining, true
|
|
case "Length/Literal":
|
|
return 2, remaining, true
|
|
case "Distance":
|
|
return 3, remaining, true
|
|
}
|
|
return 0, "", false
|
|
}
|
|
|
|
func stateDeflate(line string) (stateFunc, error) {
|
|
g := &deflateGlobals
|
|
const (
|
|
cmdB = "bytes "
|
|
cmdBDH = "blockDynamicHuffman "
|
|
cmdBFH = "blockFixedHuffman "
|
|
cmdBNC = "blockNoCompression "
|
|
)
|
|
bits := uint32(0)
|
|
s := ""
|
|
|
|
retState := stateFunc(nil)
|
|
switch {
|
|
case line == "":
|
|
g.stream.flush()
|
|
return stateDeflate, nil
|
|
|
|
case strings.HasPrefix(line, cmdB):
|
|
s := line[len(cmdB):]
|
|
for s != "" {
|
|
x, ok := uint32(0), false
|
|
x, s, ok = parseHex(s)
|
|
if !ok {
|
|
return nil, fmt.Errorf("bad stateDeflate command: %q", line)
|
|
}
|
|
out = append(out, uint8(x))
|
|
}
|
|
return stateDeflate, nil
|
|
|
|
case strings.HasPrefix(line, cmdBNC):
|
|
s = line[len(cmdBNC):]
|
|
retState = stateDeflateNoCompression
|
|
bits |= 0 << 1
|
|
case strings.HasPrefix(line, cmdBFH):
|
|
s = line[len(cmdBFH):]
|
|
retState = stateDeflateFixedHuffman
|
|
bits |= 1 << 1
|
|
case strings.HasPrefix(line, cmdBDH):
|
|
s = line[len(cmdBDH):]
|
|
retState = stateDeflateDynamicHuffman
|
|
bits |= 2 << 1
|
|
default:
|
|
return nil, fmt.Errorf("bad stateDeflate command: %q", line)
|
|
}
|
|
|
|
switch s {
|
|
case "(final) {":
|
|
bits |= 1
|
|
case "(nonFinal) {":
|
|
// No-op.
|
|
default:
|
|
return nil, fmt.Errorf("bad stateDeflate command: %q", line)
|
|
}
|
|
|
|
g.stream.writeBits(bits, 3)
|
|
return retState, nil
|
|
}
|
|
|
|
func stateDeflateNoCompression(line string) (stateFunc, error) {
|
|
g := &deflateGlobals
|
|
if line == "}" {
|
|
if len(g.bncData) > 0xFFFF {
|
|
return nil, fmt.Errorf("bncData is too long")
|
|
}
|
|
n := uint32(len(g.bncData))
|
|
g.stream.flush()
|
|
g.stream.writeBits(n, 16)
|
|
g.stream.writeBits(0xFFFF-n, 16)
|
|
g.stream.writeBytes(g.bncData)
|
|
g.bncData = g.bncData[:0]
|
|
return stateDeflate, nil
|
|
}
|
|
|
|
if lit, ok := deflateParseLiteral(line); ok {
|
|
g.bncData = append(g.bncData, lit...)
|
|
return stateDeflateNoCompression, nil
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad blockNoCompression command: %q", line)
|
|
}
|
|
|
|
func stateDeflateFixedHuffman(line string) (stateFunc, error) {
|
|
g := &deflateGlobals
|
|
if line == "}" {
|
|
return stateDeflate, nil
|
|
}
|
|
|
|
if line == "endOfBlock" {
|
|
g.stream.writeBits(0, 7)
|
|
return stateDeflateFixedHuffman, nil
|
|
}
|
|
|
|
if lit, ok := deflateParseLiteral(line); ok {
|
|
for i := 0; i < len(lit); i++ {
|
|
g.stream.writeFixedHuffmanLCode(uint32(lit[i]))
|
|
}
|
|
return stateDeflateFixedHuffman, nil
|
|
}
|
|
|
|
if line == "len 3 distCode 31" {
|
|
lCode, lExtra, lNExtra := deflateEncodeLength(3)
|
|
g.stream.writeFixedHuffmanLCode(lCode)
|
|
g.stream.writeBits(lExtra, lNExtra)
|
|
dCode, dExtra, dNExtra := uint32(31), uint32(0), uint32(0)
|
|
g.stream.writeBits(reverse(dCode, 5), 5)
|
|
g.stream.writeBits(dExtra, dNExtra)
|
|
return stateDeflateFixedHuffman, nil
|
|
}
|
|
|
|
if l, d, ok := deflateParseLenDist(line); ok {
|
|
lCode, lExtra, lNExtra := deflateEncodeLength(l)
|
|
g.stream.writeFixedHuffmanLCode(lCode)
|
|
g.stream.writeBits(lExtra, lNExtra)
|
|
dCode, dExtra, dNExtra := deflateEncodeDistance(d)
|
|
g.stream.writeBits(reverse(dCode, 5), 5)
|
|
g.stream.writeBits(dExtra, dNExtra)
|
|
return stateDeflateFixedHuffman, nil
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateDeflateFixedHuffman command: %q", line)
|
|
}
|
|
|
|
func stateDeflateDynamicHuffman(line string) (stateFunc, error) {
|
|
g := &deflateGlobals
|
|
const (
|
|
cmdH = "huffman "
|
|
cmdNCLCL = "numCLCodeLengths "
|
|
cmdNDC = "numDCodes "
|
|
cmdNLC = "numLCodes "
|
|
)
|
|
switch {
|
|
case line == "}":
|
|
deflateGlobalsClearDynamicHuffmanState()
|
|
return stateDeflate, nil
|
|
|
|
case strings.HasPrefix(line, cmdH):
|
|
s := line[len(cmdH):]
|
|
n, s, ok := parseDeflateWhichHuffman(s)
|
|
if !ok {
|
|
break
|
|
}
|
|
g.whichHuffman = n
|
|
return stateDeflateDynamicHuffmanHuffman, nil
|
|
|
|
case strings.HasPrefix(line, cmdNLC):
|
|
s := line[len(cmdNLC):]
|
|
n, s, ok := parseNum(s)
|
|
if !ok {
|
|
break
|
|
}
|
|
g.numLCodes = n
|
|
return stateDeflateDynamicHuffman, nil
|
|
|
|
case strings.HasPrefix(line, cmdNDC):
|
|
s := line[len(cmdNDC):]
|
|
n, s, ok := parseNum(s)
|
|
if !ok {
|
|
break
|
|
}
|
|
g.numDCodes = n
|
|
return stateDeflateDynamicHuffman, nil
|
|
|
|
case strings.HasPrefix(line, cmdNCLCL):
|
|
s := line[len(cmdNCLCL):]
|
|
n, s, ok := parseNum(s)
|
|
if !ok {
|
|
break
|
|
}
|
|
g.numCLCodeLengths = n
|
|
return stateDeflateDynamicHuffman, nil
|
|
}
|
|
|
|
if lit, ok := deflateParseLiteral(line); ok {
|
|
for i := 0; i < len(lit); i++ {
|
|
s := g.huffmans[2][uint32(lit[i])]
|
|
if s == "" {
|
|
return nil, fmt.Errorf("no code for literal %q (%d)", lit[i:i+1], lit[i])
|
|
}
|
|
deflateGlobalsWriteDynamicHuffmanBits(s)
|
|
}
|
|
return stateDeflateDynamicHuffman, nil
|
|
} else if line == "endOfBlock" {
|
|
s := g.huffmans[2][256]
|
|
if s == "" {
|
|
return nil, fmt.Errorf("no code for end-of-block (256)")
|
|
}
|
|
deflateGlobalsWriteDynamicHuffmanBits(s)
|
|
return stateDeflateDynamicHuffman, nil
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateDeflateDynamicHuffman command: %q", line)
|
|
}
|
|
|
|
func stateDeflateDynamicHuffmanHuffman(line string) (stateFunc, error) {
|
|
g := &deflateGlobals
|
|
outer:
|
|
switch {
|
|
case line == "}":
|
|
g.whichHuffman = 0
|
|
|
|
// If we have all three Huffman tables, write them.
|
|
for i := 1; ; i++ {
|
|
if i == 4 {
|
|
if err := deflateGlobalsWriteDynamicHuffmanTables(); err != nil {
|
|
return nil, err
|
|
}
|
|
break
|
|
}
|
|
if g.huffmans[i] == nil {
|
|
break
|
|
}
|
|
}
|
|
|
|
return stateDeflateDynamicHuffman, nil
|
|
|
|
default:
|
|
s := line
|
|
n, s, ok := parseNum(s)
|
|
if !ok || s == "" {
|
|
break
|
|
}
|
|
for i := 0; i < len(s); i++ {
|
|
if c := s[i]; c != '0' && c != '1' {
|
|
break outer
|
|
}
|
|
}
|
|
if g.huffmans[g.whichHuffman] == nil {
|
|
g.huffmans[g.whichHuffman] = deflateHuffmanTable{}
|
|
}
|
|
g.huffmans[g.whichHuffman][n] = s
|
|
return stateDeflateDynamicHuffmanHuffman, nil
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateDeflateDynamicHuffmanHuffman command: %q", line)
|
|
}
|
|
|
|
type deflateBitStream struct {
|
|
bits uint32
|
|
nBits uint32 // Always within [0, 7].
|
|
}
|
|
|
|
// writeBits writes the low n bits of b to z.
|
|
func (z *deflateBitStream) writeBits(b uint32, n uint32) {
|
|
if n > 24 {
|
|
panic("writeBits: n is too large")
|
|
}
|
|
z.bits |= b << z.nBits
|
|
z.nBits += n
|
|
for z.nBits >= 8 {
|
|
out = append(out, uint8(z.bits))
|
|
z.bits >>= 8
|
|
z.nBits -= 8
|
|
}
|
|
}
|
|
|
|
func (z *deflateBitStream) writeBytes(b []byte) {
|
|
z.flush()
|
|
out = append(out, b...)
|
|
}
|
|
|
|
func (z *deflateBitStream) writeFixedHuffmanLCode(lCode uint32) {
|
|
switch {
|
|
case lCode < 144: // 0b._0011_0000 through 0b._1011_1111
|
|
lCode += 0x030
|
|
z.writeBits(reverse(lCode, 8), 8)
|
|
case lCode < 256: // 0b1_1001_0000 through 0b1_1111_1111
|
|
lCode += 0x190 - 144
|
|
z.writeBits(reverse(lCode, 9), 9)
|
|
case lCode < 280: // 0b._.000_0000 through 0b._.001_0111
|
|
lCode -= 256 - 0x000
|
|
z.writeBits(reverse(lCode, 7), 7)
|
|
default: // 0b._1100_0000 through 0b._1100_0111
|
|
lCode -= 280 - 0x0C0
|
|
z.writeBits(reverse(lCode, 8), 8)
|
|
}
|
|
}
|
|
|
|
func (z *deflateBitStream) flush() {
|
|
if z.nBits > 0 {
|
|
out = append(out, uint8(z.bits))
|
|
z.bits = 0
|
|
z.nBits = 0
|
|
}
|
|
}
|
|
|
|
func deflateEncodeLength(l uint32) (code uint32, extra uint32, nExtra uint32) {
|
|
switch {
|
|
case l < 3:
|
|
// No-op.
|
|
case l < 11:
|
|
l -= 3
|
|
return (l >> 0) + 257, l & 0x0000, 0
|
|
case l < 19:
|
|
l -= 11
|
|
return (l >> 1) + 265, l & 0x0001, 1
|
|
case l < 35:
|
|
l -= 19
|
|
return (l >> 2) + 269, l & 0x0003, 2
|
|
case l < 67:
|
|
l -= 35
|
|
return (l >> 3) + 273, l & 0x0007, 3
|
|
case l < 131:
|
|
l -= 67
|
|
return (l >> 4) + 277, l & 0x000F, 4
|
|
case l < 258:
|
|
l -= 131
|
|
return (l >> 5) + 281, l & 0x001F, 5
|
|
case l == 258:
|
|
return 285, 0, 0
|
|
}
|
|
panic(fmt.Sprintf("deflateEncodeLength: l=%d", l))
|
|
}
|
|
|
|
func deflateEncodeDistance(d uint32) (code uint32, extra uint32, nExtra uint32) {
|
|
switch {
|
|
case d < 1:
|
|
// No-op.
|
|
case d < 5:
|
|
d -= 1
|
|
return (d >> 0) + 0, d & 0x0000, 0
|
|
case d < 9:
|
|
d -= 5
|
|
return (d >> 1) + 4, d & 0x0001, 1
|
|
case d < 17:
|
|
d -= 9
|
|
return (d >> 2) + 6, d & 0x0003, 2
|
|
case d < 33:
|
|
d -= 17
|
|
return (d >> 3) + 8, d & 0x0007, 3
|
|
case d < 65:
|
|
d -= 33
|
|
return (d >> 4) + 10, d & 0x000F, 4
|
|
case d < 129:
|
|
d -= 65
|
|
return (d >> 5) + 12, d & 0x001F, 5
|
|
case d < 257:
|
|
d -= 129
|
|
return (d >> 6) + 14, d & 0x003F, 6
|
|
case d < 513:
|
|
d -= 257
|
|
return (d >> 7) + 16, d & 0x007F, 7
|
|
case d < 1025:
|
|
d -= 513
|
|
return (d >> 8) + 18, d & 0x00FF, 8
|
|
case d < 2049:
|
|
d -= 1025
|
|
return (d >> 9) + 20, d & 0x01FF, 9
|
|
case d < 4097:
|
|
d -= 2049
|
|
return (d >> 10) + 22, d & 0x03FF, 10
|
|
case d < 8193:
|
|
d -= 4097
|
|
return (d >> 11) + 24, d & 0x07FF, 11
|
|
case d < 16385:
|
|
d -= 8193
|
|
return (d >> 12) + 26, d & 0x0FFF, 12
|
|
case d < 32769:
|
|
d -= 16385
|
|
return (d >> 13) + 28, d & 0x1FFF, 13
|
|
}
|
|
panic(fmt.Sprintf("deflateEncodeDistance: d=%d", d))
|
|
}
|
|
|
|
func deflateParseLiteral(s string) (lit string, ok bool) {
|
|
// TODO: support "\xAB" escape codes in the script?
|
|
const (
|
|
prefix = `literal "`
|
|
suffix = `"`
|
|
)
|
|
if strings.HasPrefix(s, prefix) {
|
|
s = s[len(prefix):]
|
|
if strings.HasSuffix(s, suffix) {
|
|
return s[:len(s)-len(suffix)], true
|
|
}
|
|
}
|
|
return "", false
|
|
}
|
|
|
|
func deflateParseLenDist(line string) (l uint32, d uint32, ok bool) {
|
|
const (
|
|
lStr = "len "
|
|
dStr = "dist "
|
|
)
|
|
s := line
|
|
if strings.HasPrefix(s, lStr) {
|
|
s = s[len(lStr):]
|
|
if l, s, ok := parseNum(s); ok && 3 <= l && l <= 258 {
|
|
if strings.HasPrefix(s, dStr) {
|
|
s = s[len(dStr):]
|
|
if d, s, ok := parseNum(s); ok && 1 <= d && d <= 32768 && s == "" {
|
|
return l, d, true
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return 0, 0, false
|
|
}
|
|
|
|
// ----
|
|
|
|
func init() {
|
|
formats["gif"] = stateGif
|
|
}
|
|
|
|
var gifGlobals struct {
|
|
imageWidth uint32
|
|
imageHeight uint32
|
|
imageBackgroundColorIndex uint32
|
|
|
|
frameLeft uint32
|
|
frameTop uint32
|
|
frameWidth uint32
|
|
frameHeight uint32
|
|
|
|
globalPalette [][4]uint8
|
|
localPalette [][4]uint8
|
|
}
|
|
|
|
func stateGif(line string) (stateFunc, error) {
|
|
const (
|
|
cmdB = "bytes "
|
|
cmdGC = "graphicControl "
|
|
cmdL = "lzw "
|
|
cmdLC = "loopCount "
|
|
)
|
|
outer:
|
|
switch {
|
|
case line == "":
|
|
return stateGif, nil
|
|
|
|
case line == "frame {":
|
|
gifGlobals.localPalette = nil
|
|
out = append(out, 0x2C)
|
|
return stateGifFrame, nil
|
|
|
|
case line == "header":
|
|
out = append(out, "GIF89a"...)
|
|
return stateGif, nil
|
|
|
|
case line == "image {":
|
|
return stateGifImage, nil
|
|
|
|
case line == "trailer":
|
|
out = append(out, 0x3B)
|
|
return stateGif, nil
|
|
|
|
case strings.HasPrefix(line, cmdB):
|
|
s := line[len(cmdB):]
|
|
for s != "" {
|
|
x, ok := uint32(0), false
|
|
x, s, ok = parseHex(s)
|
|
if !ok {
|
|
break outer
|
|
}
|
|
out = append(out, uint8(x))
|
|
}
|
|
return stateGif, nil
|
|
|
|
case strings.HasPrefix(line, cmdGC):
|
|
s := line[len(cmdGC):]
|
|
|
|
flags := uint8(0)
|
|
if i := strings.IndexByte(s, ' '); i < 0 {
|
|
break
|
|
} else {
|
|
switch s[:i] {
|
|
case "animationDisposalNone":
|
|
flags |= 0x00
|
|
case "animationDisposalRestoreBackground":
|
|
flags |= 0x08
|
|
case "animationDisposalRestorePrevious":
|
|
flags |= 0x0C
|
|
default:
|
|
break outer
|
|
}
|
|
s = s[i+1:]
|
|
}
|
|
|
|
if !strings.HasSuffix(s, "ms") {
|
|
break
|
|
}
|
|
s = s[:len(s)-2]
|
|
duration, s, ok := parseNum(s)
|
|
if !ok || s != "" {
|
|
break
|
|
}
|
|
duration /= 10 // GIF's unit of time is 10ms.
|
|
|
|
transparentIndex := uint8(0)
|
|
|
|
out = append(out,
|
|
0x21, 0xF9, 0x04,
|
|
flags,
|
|
uint8(duration>>0),
|
|
uint8(duration>>8),
|
|
transparentIndex,
|
|
0x00,
|
|
)
|
|
return stateGif, nil
|
|
|
|
case strings.HasPrefix(line, cmdL):
|
|
s := line[len(cmdL):]
|
|
litWidth, s, ok := parseNum(s)
|
|
if !ok || litWidth < 2 || 8 < litWidth {
|
|
break
|
|
}
|
|
out = append(out, uint8(litWidth))
|
|
|
|
uncompressed := []byte(nil)
|
|
for s != "" {
|
|
x := uint32(0)
|
|
x, s, ok = parseHex(s)
|
|
if !ok {
|
|
break outer
|
|
}
|
|
uncompressed = append(uncompressed, uint8(x))
|
|
}
|
|
|
|
buf := bytes.NewBuffer(nil)
|
|
w := lzw.NewWriter(buf, lzw.LSB, int(litWidth))
|
|
if _, err := w.Write(uncompressed); err != nil {
|
|
return nil, err
|
|
}
|
|
if err := w.Close(); err != nil {
|
|
return nil, err
|
|
}
|
|
compressed := buf.Bytes()
|
|
|
|
for len(compressed) > 0 {
|
|
if len(compressed) <= 0xFF {
|
|
out = append(out, uint8(len(compressed)))
|
|
out = append(out, compressed...)
|
|
compressed = nil
|
|
} else {
|
|
out = append(out, 0xFF)
|
|
out = append(out, compressed[:0xFF]...)
|
|
compressed = compressed[0xFF:]
|
|
}
|
|
}
|
|
out = append(out, 0x00)
|
|
return stateGif, nil
|
|
|
|
case strings.HasPrefix(line, cmdLC):
|
|
s := line[len(cmdLC):]
|
|
loopCount, _, ok := parseNum(s)
|
|
if !ok || 0xFFFF < loopCount {
|
|
break
|
|
}
|
|
out = append(out,
|
|
0x21, // Extension Introducer.
|
|
0xFF, // Application Extension Label.
|
|
0x0B, // Block Size.
|
|
)
|
|
out = append(out, "NETSCAPE2.0"...)
|
|
out = append(out,
|
|
0x03, // Block Size.
|
|
0x01, // Magic Number.
|
|
byte(loopCount),
|
|
byte(loopCount>>8),
|
|
0x00, // Block Terminator.
|
|
)
|
|
return stateGif, nil
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateGif command: %q", line)
|
|
}
|
|
|
|
func stateGifImage(line string) (stateFunc, error) {
|
|
g := &gifGlobals
|
|
if line == "}" {
|
|
out = appendU16LE(out, uint16(g.imageWidth))
|
|
out = appendU16LE(out, uint16(g.imageHeight))
|
|
if g.globalPalette == nil {
|
|
out = append(out, 0x00)
|
|
} else if n := log2(uint32(len(g.globalPalette))); n < 2 || 8 < n {
|
|
return nil, fmt.Errorf("bad len(g.globalPalette): %d", len(g.globalPalette))
|
|
} else {
|
|
out = append(out, 0x80|uint8(n-1))
|
|
}
|
|
out = append(out, uint8(g.imageBackgroundColorIndex))
|
|
out = append(out, 0x00)
|
|
for _, x := range g.globalPalette {
|
|
out = append(out, x[0], x[1], x[2])
|
|
}
|
|
return stateGif, nil
|
|
}
|
|
|
|
const (
|
|
cmdBCI = "backgroundColorIndex "
|
|
cmdIWH = "imageWidthHeight "
|
|
cmdP = "palette {"
|
|
)
|
|
switch {
|
|
case strings.HasPrefix(line, cmdBCI):
|
|
s := line[len(cmdBCI):]
|
|
if i, _, ok := parseNum(s); ok {
|
|
g.imageBackgroundColorIndex = i
|
|
}
|
|
return stateGifImage, nil
|
|
|
|
case strings.HasPrefix(line, cmdIWH):
|
|
s := line[len(cmdIWH):]
|
|
if w, s, ok := parseNum(s); ok {
|
|
if h, _, ok := parseNum(s); ok {
|
|
g.imageWidth = w
|
|
g.imageHeight = h
|
|
return stateGifImage, nil
|
|
}
|
|
}
|
|
|
|
case strings.HasPrefix(line, cmdP):
|
|
return stateGifImagePalette, nil
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateGifImage command: %q", line)
|
|
}
|
|
|
|
func stateGifFrame(line string) (stateFunc, error) {
|
|
g := &gifGlobals
|
|
if line == "}" {
|
|
out = appendU16LE(out, uint16(g.frameLeft))
|
|
out = appendU16LE(out, uint16(g.frameTop))
|
|
out = appendU16LE(out, uint16(g.frameWidth))
|
|
out = appendU16LE(out, uint16(g.frameHeight))
|
|
if g.localPalette == nil {
|
|
out = append(out, 0x00)
|
|
} else if n := log2(uint32(len(g.localPalette))); n < 2 || 8 < n {
|
|
return nil, fmt.Errorf("bad len(g.localPalette): %d", len(g.localPalette))
|
|
} else {
|
|
out = append(out, 0x80|uint8(n-1))
|
|
}
|
|
for _, x := range g.localPalette {
|
|
out = append(out, x[0], x[1], x[2])
|
|
}
|
|
return stateGif, nil
|
|
}
|
|
|
|
const (
|
|
cmdFLTWH = "frameLeftTopWidthHeight "
|
|
cmdP = "palette {"
|
|
)
|
|
switch {
|
|
case strings.HasPrefix(line, cmdFLTWH):
|
|
s := line[len(cmdFLTWH):]
|
|
if l, s, ok := parseNum(s); ok {
|
|
if t, s, ok := parseNum(s); ok {
|
|
if w, s, ok := parseNum(s); ok {
|
|
if h, _, ok := parseNum(s); ok {
|
|
g.frameLeft = l
|
|
g.frameTop = t
|
|
g.frameWidth = w
|
|
g.frameHeight = h
|
|
return stateGifFrame, nil
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
case strings.HasPrefix(line, cmdP):
|
|
return stateGifFramePalette, nil
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateGifFrame command: %q", line)
|
|
}
|
|
|
|
func stateGifImagePalette(line string) (stateFunc, error) {
|
|
g := &gifGlobals
|
|
if line == "}" {
|
|
return stateGifImage, nil
|
|
}
|
|
|
|
s := line
|
|
if rgb0, s, ok := parseHex(s); ok {
|
|
if rgb1, s, ok := parseHex(s); ok {
|
|
if rgb2, _, ok := parseHex(s); ok {
|
|
g.globalPalette = append(g.globalPalette,
|
|
[4]uint8{uint8(rgb0), uint8(rgb1), uint8(rgb2), 0xFF})
|
|
return stateGifImagePalette, nil
|
|
}
|
|
}
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateGifImagePalette command: %q", line)
|
|
}
|
|
|
|
func stateGifFramePalette(line string) (stateFunc, error) {
|
|
g := &gifGlobals
|
|
if line == "}" {
|
|
return stateGifFrame, nil
|
|
}
|
|
|
|
s := line
|
|
if rgb0, s, ok := parseHex(s); ok {
|
|
if rgb1, s, ok := parseHex(s); ok {
|
|
if rgb2, _, ok := parseHex(s); ok {
|
|
g.localPalette = append(g.localPalette,
|
|
[4]uint8{uint8(rgb0), uint8(rgb1), uint8(rgb2), 0xFF})
|
|
return stateGifFramePalette, nil
|
|
}
|
|
}
|
|
}
|
|
|
|
return nil, fmt.Errorf("bad stateGifFramePalette command: %q", line)
|
|
}
|