diff options
Diffstat (limited to 'src/pkg/go/scanner/scanner.go')
| -rw-r--r-- | src/pkg/go/scanner/scanner.go | 118 |
1 files changed, 72 insertions, 46 deletions
diff --git a/src/pkg/go/scanner/scanner.go b/src/pkg/go/scanner/scanner.go index 1e259d5ed..cec82ea10 100644 --- a/src/pkg/go/scanner/scanner.go +++ b/src/pkg/go/scanner/scanner.go @@ -148,11 +148,14 @@ func (s *Scanner) interpretLineComment(text []byte) { // get filename and line number, if any if i := bytes.LastIndex(text, []byte{':'}); i > 0 { if line, err := strconv.Atoi(string(text[i+1:])); err == nil && line > 0 { - // valid //line filename:line comment; - filename := filepath.Clean(string(text[len(prefix):i])) - if !filepath.IsAbs(filename) { - // make filename relative to current directory - filename = filepath.Join(s.dir, filename) + // valid //line filename:line comment + filename := string(bytes.TrimSpace(text[len(prefix):i])) + if filename != "" { + filename = filepath.Clean(filename) + if !filepath.IsAbs(filename) { + // make filename relative to current directory + filename = filepath.Join(s.dir, filename) + } } // update scanner position s.file.AddLineInfo(s.lineOffset+len(text)+1, filename, line) // +len(text)+1 since comment applies to next line @@ -358,73 +361,94 @@ exit: return tok, string(s.src[offs:s.offset]) } -func (s *Scanner) scanEscape(quote rune) { +// scanEscape parses an escape sequence where rune is the accepted +// escaped quote. In case of a syntax error, it stops at the offending +// character (without consuming it) and returns false. Otherwise +// it returns true. +func (s *Scanner) scanEscape(quote rune) bool { offs := s.offset - var i, base, max uint32 + var n int + var base, max uint32 switch s.ch { case 'a', 'b', 'f', 'n', 'r', 't', 'v', '\\', quote: s.next() - return + return true case '0', '1', '2', '3', '4', '5', '6', '7': - i, base, max = 3, 8, 255 + n, base, max = 3, 8, 255 case 'x': s.next() - i, base, max = 2, 16, 255 + n, base, max = 2, 16, 255 case 'u': s.next() - i, base, max = 4, 16, unicode.MaxRune + n, base, max = 4, 16, unicode.MaxRune case 'U': s.next() - i, base, max = 8, 16, unicode.MaxRune + n, base, max = 8, 16, unicode.MaxRune default: - s.next() // always make progress - s.error(offs, "unknown escape sequence") - return + msg := "unknown escape sequence" + if s.ch < 0 { + msg = "escape sequence not terminated" + } + s.error(offs, msg) + return false } var x uint32 - for ; i > 0 && s.ch != quote && s.ch >= 0; i-- { + for n > 0 { d := uint32(digitVal(s.ch)) if d >= base { - s.error(s.offset, "illegal character in escape sequence") - break + msg := fmt.Sprintf("illegal character %#U in escape sequence", s.ch) + if s.ch < 0 { + msg = "escape sequence not terminated" + } + s.error(s.offset, msg) + return false } x = x*base + d s.next() + n-- } - // in case of an error, consume remaining chars - for ; i > 0 && s.ch != quote && s.ch >= 0; i-- { - s.next() - } + if x > max || 0xD800 <= x && x < 0xE000 { s.error(offs, "escape sequence is invalid Unicode code point") + return false } + + return true } -func (s *Scanner) scanChar() string { +func (s *Scanner) scanRune() string { // '\'' opening already consumed offs := s.offset - 1 + valid := true n := 0 - for s.ch != '\'' { + for { ch := s.ch - n++ - s.next() if ch == '\n' || ch < 0 { - s.error(offs, "character literal not terminated") - n = 1 + // only report error if we don't have one already + if valid { + s.error(offs, "rune literal not terminated") + valid = false + } break } + s.next() + if ch == '\'' { + break + } + n++ if ch == '\\' { - s.scanEscape('\'') + if !s.scanEscape('\'') { + valid = false + } + // continue to read to closing quote } } - s.next() - - if n != 1 { - s.error(offs, "illegal character literal") + if valid && n != 1 { + s.error(offs, "illegal rune literal") } return string(s.src[offs:s.offset]) @@ -434,11 +458,14 @@ func (s *Scanner) scanString() string { // '"' opening already consumed offs := s.offset - 1 - for s.ch != '"' { + for { ch := s.ch - s.next() if ch == '\n' || ch < 0 { - s.error(offs, "string not terminated") + s.error(offs, "string literal not terminated") + break + } + s.next() + if ch == '"' { break } if ch == '\\' { @@ -446,8 +473,6 @@ func (s *Scanner) scanString() string { } } - s.next() - return string(s.src[offs:s.offset]) } @@ -468,20 +493,21 @@ func (s *Scanner) scanRawString() string { offs := s.offset - 1 hasCR := false - for s.ch != '`' { + for { ch := s.ch + if ch < 0 { + s.error(offs, "raw string literal not terminated") + break + } s.next() + if ch == '`' { + break + } if ch == '\r' { hasCR = true } - if ch < 0 { - s.error(offs, "string not terminated") - break - } } - s.next() - lit := s.src[offs:s.offset] if hasCR { lit = stripCR(lit) @@ -617,7 +643,7 @@ scanAgain: case '\'': insertSemi = true tok = token.CHAR - lit = s.scanChar() + lit = s.scanRune() case '`': insertSemi = true tok = token.STRING |