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|
// Code generated by re2go, DO NOT EDIT.
//line "codegen/go/003_fill_bf.re":1
//go:generate re2go $INPUT -o $OUTPUT -bf
package main
import "fmt"
import "os"
//line "codegen/go/003_fill_bf.go":10
const YYMAXFILL = 2
//line "codegen/go/003_fill_bf.re":7
var SIZE uint = 11
type YYCTYPE byte
type Input struct {
file *os.File
data []byte
cursor uint
marker uint
token uint
limit uint
eof bool
state int
}
const (
lexError = iota
lexNeedMoreSpace
lexNeedMoreInput
lexResume
lexEnd
lexNumber1
lexNumber2
lexSpace
)
func fill(in *Input, need uint) int {
// End of input has already been reached, nothing to do.
if in.eof {
fmt.Println("fill error: unexpected EOF")
return lexError
}
// Check if after moving the current lexeme to the beginning
// of buffer there will be enough free space.
if SIZE-(in.cursor-in.token) < need {
fmt.Println("fill error: lexeme too long")
return lexNeedMoreSpace
}
// Discard everything up to the start of the current lexeme,
// shift buffer contents and adjust offsets.
copy(in.data[0:], in.data[in.token:in.limit])
in.cursor -= in.token
in.marker -= in.token
in.limit -= in.token
in.token = 0
// Read new data (as much as possible to fill the buffer).
n, _ := in.file.Read(in.data[in.limit:SIZE])
in.limit += uint(n)
fmt.Printf("fill(%u): %v '%s'\n", need, in.data[:in.limit+1],
string(in.data[:in.limit]))
// If read less than expected, this is the end of input.
in.eof = in.limit < SIZE
// If end of input, add padding so that the lexer can read
// the remaining characters at the end of buffer.
if in.eof {
for i := uint(0); i < YYMAXFILL; i += 1 {
in.data[in.limit+i] = 0
}
in.limit += YYMAXFILL
}
return lexResume
}
func Lex(in *Input) (int, uint) {
var yych YYCTYPE
//line "codegen/go/003_fill_bf.go":86
{
yybm := [256]byte{
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
64, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
128, 128, 128, 128, 128, 128, 128, 128,
128, 128, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
}
switch (in.state) {
case 0:
goto yyFillLabel0
case 1:
goto yyFillLabel1
case 2:
goto yyFillLabel2
case 3:
goto yyFillLabel3
default:
goto yy0
}
yy0:
if (in.limit-in.cursor < 1) {
in.state = 0
return lexNeedMoreInput, 1
}
yyFillLabel0:
yych = YYCTYPE(in.data[in.cursor])
if ((yybm[0+yych] & 64) != 0) {
goto yy4
}
if (yych <= 0x00) {
goto yy2
}
if (yych <= '/') {
goto yy3
}
if (yych <= '9') {
goto yy5
}
goto yy3
yy2:
in.cursor += 1
in.state = -1
//line "codegen/go/003_fill_bf.re":94
{
fmt.Println("end")
return lexEnd, 0
}
//line "codegen/go/003_fill_bf.go":162
yy3:
in.cursor += 1
in.state = -1
//line "codegen/go/003_fill_bf.re":89
{
fmt.Println("error")
return lexError, 0
}
//line "codegen/go/003_fill_bf.go":171
yy4:
in.cursor += 1
if (in.limit-in.cursor < 1) {
in.state = 1
return lexNeedMoreInput, 1
}
yyFillLabel1:
yych = YYCTYPE(in.data[in.cursor])
if ((yybm[0+yych] & 64) != 0) {
goto yy4
}
in.state = -1
//line "codegen/go/003_fill_bf.re":109
{
return lexSpace, 0
}
//line "codegen/go/003_fill_bf.go":188
yy5:
in.cursor += 1
in.marker = in.cursor
if (in.limit-in.cursor < 2) {
in.state = 2
return lexNeedMoreInput, 2
}
yyFillLabel2:
yych = YYCTYPE(in.data[in.cursor])
if ((yybm[0+yych] & 128) != 0) {
goto yy5
}
if (yych == '-') {
goto yy7
}
yy6:
in.state = -1
//line "codegen/go/003_fill_bf.re":99
{
fmt.Printf("number-1: %v\n", string(in.data[in.token:in.cursor]))
return lexNumber1, 0
}
//line "codegen/go/003_fill_bf.go":211
yy7:
in.cursor += 1
yych = YYCTYPE(in.data[in.cursor])
if (yych <= '/') {
goto yy8
}
if (yych <= '9') {
goto yy9
}
yy8:
in.cursor = in.marker
goto yy6
yy9:
in.cursor += 1
if (in.limit-in.cursor < 1) {
in.state = 3
return lexNeedMoreInput, 1
}
yyFillLabel3:
yych = YYCTYPE(in.data[in.cursor])
if (yych <= '/') {
goto yy10
}
if (yych <= '9') {
goto yy9
}
yy10:
in.state = -1
//line "codegen/go/003_fill_bf.re":104
{
fmt.Printf("number-2: %v\n", string(in.data[in.token:in.cursor]))
return lexNumber2, 0
}
//line "codegen/go/003_fill_bf.go":245
}
//line "codegen/go/003_fill_bf.re":112
}
func test(data string) int {
tmpfile := "input.txt"
f, _ := os.Create(tmpfile)
f.WriteString(data)
f.WriteString("\000") // lexer expects NULL-terminator
f.Seek(0, 0)
defer func() {
f.Close()
os.Remove(tmpfile)
}()
in := &Input{
file: f,
data: make([]byte, SIZE+YYMAXFILL),
cursor: SIZE,
marker: SIZE,
token: SIZE,
limit: SIZE,
eof: false,
}
need := uint(1)
result := lexNeedMoreInput
loop:
for {
switch result {
case lexError:
break loop
case lexEnd:
break loop
case lexNeedMoreInput:
result = fill(in, need)
if result != lexResume {
break loop
}
default:
in.token = in.cursor
in.state = 0
}
result, need = Lex(in)
}
return result
}
func main() {
var s string
// Succeeds, the lexer has enough characters ahead.
s = " 123456789 "
if test(s) != lexEnd {
panic("expected 'number: 123456789'")
}
// Fails, there is no space for the needed characters.
s = " 1234567890 "
if test(s) != lexNeedMoreSpace {
panic("expected 'fill error: lexeme too long'")
}
// Succeeds, the lexer has enough characters ahead
// (although the same lexeme length as the previous case,
// YYFILL argument is smaller in this state).
s = " 12345-6789 "
if test(s) != lexEnd {
panic("expected 'number: 12345-6789'")
}
// Fails, there is no space for any characters.
s = " 12345-67890 "
if test(s) != lexNeedMoreSpace {
panic("expected 'fill error: lexeme too long'")
}
// Fails, invalid input.
s = "?#!*"
if test(s) != lexError {
panic("expected 'error'")
}
fmt.Println("OK")
}
|
