peridot/vendor/github.com/aws/aws-sdk-go/internal/ini/ini_lexer.go
2022-07-07 22:13:21 +02:00

166 lines
3.0 KiB
Go

package ini
import (
"bytes"
"io"
"io/ioutil"
"github.com/aws/aws-sdk-go/aws/awserr"
)
const (
// ErrCodeUnableToReadFile is used when a file is failed to be
// opened or read from.
ErrCodeUnableToReadFile = "FailedRead"
)
// TokenType represents the various different tokens types
type TokenType int
func (t TokenType) String() string {
switch t {
case TokenNone:
return "none"
case TokenLit:
return "literal"
case TokenSep:
return "sep"
case TokenOp:
return "op"
case TokenWS:
return "ws"
case TokenNL:
return "newline"
case TokenComment:
return "comment"
case TokenComma:
return "comma"
default:
return ""
}
}
// TokenType enums
const (
TokenNone = TokenType(iota)
TokenLit
TokenSep
TokenComma
TokenOp
TokenWS
TokenNL
TokenComment
)
type iniLexer struct{}
// Tokenize will return a list of tokens during lexical analysis of the
// io.Reader.
func (l *iniLexer) Tokenize(r io.Reader) ([]Token, error) {
b, err := ioutil.ReadAll(r)
if err != nil {
return nil, awserr.New(ErrCodeUnableToReadFile, "unable to read file", err)
}
return l.tokenize(b)
}
func (l *iniLexer) tokenize(b []byte) ([]Token, error) {
runes := bytes.Runes(b)
var err error
n := 0
tokenAmount := countTokens(runes)
tokens := make([]Token, tokenAmount)
count := 0
for len(runes) > 0 && count < tokenAmount {
switch {
case isWhitespace(runes[0]):
tokens[count], n, err = newWSToken(runes)
case isComma(runes[0]):
tokens[count], n = newCommaToken(), 1
case isComment(runes):
tokens[count], n, err = newCommentToken(runes)
case isNewline(runes):
tokens[count], n, err = newNewlineToken(runes)
case isSep(runes):
tokens[count], n, err = newSepToken(runes)
case isOp(runes):
tokens[count], n, err = newOpToken(runes)
default:
tokens[count], n, err = newLitToken(runes)
}
if err != nil {
return nil, err
}
count++
runes = runes[n:]
}
return tokens[:count], nil
}
func countTokens(runes []rune) int {
count, n := 0, 0
var err error
for len(runes) > 0 {
switch {
case isWhitespace(runes[0]):
_, n, err = newWSToken(runes)
case isComma(runes[0]):
_, n = newCommaToken(), 1
case isComment(runes):
_, n, err = newCommentToken(runes)
case isNewline(runes):
_, n, err = newNewlineToken(runes)
case isSep(runes):
_, n, err = newSepToken(runes)
case isOp(runes):
_, n, err = newOpToken(runes)
default:
_, n, err = newLitToken(runes)
}
if err != nil {
return 0
}
count++
runes = runes[n:]
}
return count + 1
}
// Token indicates a metadata about a given value.
type Token struct {
t TokenType
ValueType ValueType
base int
raw []rune
}
var emptyValue = Value{}
func newToken(t TokenType, raw []rune, v ValueType) Token {
return Token{
t: t,
raw: raw,
ValueType: v,
}
}
// Raw return the raw runes that were consumed
func (tok Token) Raw() []rune {
return tok.raw
}
// Type returns the token type
func (tok Token) Type() TokenType {
return tok.t
}