コード例 #1
0
ファイル: main.go プロジェクト: XuHuaiyu/tidb
func main1(in string) (err error) {
	var out io.Writer
	if nm := *oOut; nm != "" {
		var f *os.File
		var e error
		if f, err = os.Create(nm); err != nil {
			return err
		}

		defer func() {
			if e1 := f.Close(); e1 != nil && err == nil {
				err = e1
			}
		}()
		w := bufio.NewWriter(f)
		defer func() {
			if e1 := w.Flush(); e1 != nil && err == nil {
				err = e1
			}
		}()
		buf := bytes.NewBuffer(nil)
		out = buf
		defer func() {
			var dest []byte
			if dest, e = format.Source(buf.Bytes()); e != nil {
				dest = buf.Bytes()
			}

			if _, e = w.Write(dest); e != nil && err == nil {
				err = e
			}
		}()
	}

	var rep io.Writer
	if nm := *oReport; nm != "" {
		f, err1 := os.Create(nm)
		if err1 != nil {
			return err1
		}

		defer func() {
			if e := f.Close(); e != nil && err == nil {
				err = e
			}
		}()
		w := bufio.NewWriter(f)
		defer func() {
			if e := w.Flush(); e != nil && err == nil {
				err = e
			}
		}()
		rep = w
	}

	var xerrors []byte
	if nm := *oXErrors; nm != "" {
		b, err1 := ioutil.ReadFile(nm)
		if err1 != nil {
			return err1
		}

		xerrors = b
	}

	p, err := y.ProcessFile(token.NewFileSet(), in, &y.Options{
		//NoDefault:   *oNoDefault,
		AllowConflicts: true,
		Closures:       *oClosures,
		LA:             *oLA,
		Reducible:      *oReducible,
		Report:         rep,
		Resolved:       *oResolved,
		XErrorsName:    *oXErrors,
		XErrorsSrc:     xerrors,
	})
	if err != nil {
		return err
	}

	if fn := *oXErrorsGen; fn != "" {
		f, err := os.OpenFile(fn, os.O_RDWR|os.O_CREATE, 0666)
		if err != nil {
			return err
		}

		b := bufio.NewWriter(f)
		if err := p.SkeletonXErrors(b); err != nil {
			return err
		}

		if err := b.Flush(); err != nil {
			return err
		}

		if err := f.Close(); err != nil {
			return err
		}
	}

	msu := make(map[*y.Symbol]int, len(p.Syms)) // sym -> usage
	for nm, sym := range p.Syms {
		if nm == "" || nm == "ε" || nm == "$accept" || nm == "#" {
			continue
		}

		msu[sym] = 0
	}
	var minArg, maxArg int
	for _, state := range p.Table {
		for _, act := range state {
			msu[act.Sym]++
			k, arg := act.Kind()
			if k == 'a' {
				continue
			}

			if k == 'r' {
				arg = -arg
			}
			minArg, maxArg = mathutil.Min(minArg, arg), mathutil.Max(maxArg, arg)
		}
	}
	su := make(symsUsed, 0, len(msu))
	for sym, used := range msu {
		su = append(su, symUsed{sym, used})
	}
	sort.Sort(su)

	// ----------------------------------------------------------- Prologue
	f := strutil.IndentFormatter(out, "\t")
	f.Format("// CAUTION: Generated file - DO NOT EDIT.\n\n")
	f.Format("%s", injectImport(p.Prologue))
	f.Format(`
type %[1]sSymType %i%s%u

type %[1]sXError struct {
	state, xsym int
}
`, *oPref, p.UnionSrc)

	// ---------------------------------------------------------- Constants
	nsyms := map[string]*y.Symbol{}
	a := make([]string, 0, len(msu))
	maxTokName := 0
	for sym := range msu {
		nm := sym.Name
		if nm == "$default" || nm == "$end" || sym.IsTerminal && nm[0] != '\'' && sym.Value > 0 {
			maxTokName = mathutil.Max(maxTokName, len(nm))
			a = append(a, nm)
		}
		nsyms[nm] = sym
	}
	sort.Strings(a)
	f.Format("\nconst (%i\n")
	for _, v := range a {
		nm := v
		switch nm {
		case "error":
			nm = *oPref + "ErrCode"
		case "$default":
			nm = *oPref + "Default"
		case "$end":
			nm = *oPref + "EofCode"
		}
		f.Format("%s%s = %d\n", nm, strings.Repeat(" ", maxTokName-len(nm)+1), nsyms[v].Value)
	}
	minArg-- // eg: [-13, 42], minArg -14 maps -13 to 1 so zero cell values -> empty.
	f.Format("\n%sMaxDepth = 200\n", *oPref)
	f.Format("%sTabOfs   = %d\n", *oPref, minArg)
	f.Format("%u)")

	// ---------------------------------------------------------- Variables
	f.Format("\n\nvar (%i\n")

	// Lex translation table
	f.Format("%sXLAT = map[int]int{%i\n", *oPref)
	xlat := make(map[int]int, len(su))
	var errSym int
	for i, v := range su {
		if v.sym.Name == "error" {
			errSym = i
		}
		xlat[v.sym.Value] = i
		f.Format("%6d: %3d, // %s (%dx)\n", v.sym.Value, i, v.sym.Name, msu[v.sym])
	}
	f.Format("%u}\n")

	// Symbol names
	f.Format("\n%sSymNames = []string{%i\n", *oPref)
	for _, v := range su {
		f.Format("%q,\n", v.sym.Name)
	}
	f.Format("%u}\n")

	// Reduction table
	f.Format("\n%sReductions = []struct{xsym, components int}{%i\n", *oPref)
	for _, rule := range p.Rules {
		f.Format("{%d, %d},\n", xlat[rule.Sym.Value], len(rule.Components))
	}
	f.Format("%u}\n")

	// XError table
	f.Format("\n%[1]sXErrors = map[%[1]sXError]string{%i\n", *oPref)
	for _, xerr := range p.XErrors {
		state := xerr.Stack[len(xerr.Stack)-1]
		xsym := -1
		if xerr.Lookahead != nil {
			xsym = xlat[xerr.Lookahead.Value]
		}
		f.Format("%[1]sXError{%d, %d}: \"%s\",\n", *oPref, state, xsym, xerr.Msg)
	}
	f.Format("%u}\n\n")

	// Parse table
	tbits := 32
	switch n := mathutil.BitLen(maxArg - minArg + 1); {
	case n < 8:
		tbits = 8
	case n < 16:
		tbits = 16
	}
	f.Format("%sParseTab = [%d][]uint%d{%i\n", *oPref, len(p.Table), tbits)
	nCells := 0
	var tabRow sortutil.Uint64Slice
	for si, state := range p.Table {
		tabRow = tabRow[:0]
		max := 0
		for _, act := range state {
			sym := act.Sym
			xsym, ok := xlat[sym.Value]
			if !ok {
				panic("internal error 001")
			}

			max = mathutil.Max(max, xsym)
			kind, arg := act.Kind()
			switch kind {
			case 'a':
				arg = 0
			case 'r':
				arg *= -1
			}
			tabRow = append(tabRow, uint64(xsym)<<32|uint64(arg-minArg))
		}
		nCells += max
		tabRow.Sort()
		col := -1
		if si%5 == 0 {
			f.Format("// %d\n", si)
		}
		f.Format("{")
		for i, v := range tabRow {
			xsym := int(uint32(v >> 32))
			arg := int(uint32(v))
			if col+1 != xsym {
				f.Format("%d: ", xsym)
			}
			switch {
			case i == len(tabRow)-1:
				f.Format("%d", arg)
			default:
				f.Format("%d, ", arg)
			}
			col = xsym
		}
		f.Format("},\n")
	}
	f.Format("%u}\n")
	fmt.Fprintf(os.Stderr, "Parse table entries: %d of %d, x %d bits == %d bytes\n", nCells, len(p.Table)*len(msu), tbits, nCells*tbits/8)
	if n := p.ConflictsSR; n != 0 {
		fmt.Fprintf(os.Stderr, "conflicts: %d shift/reduce\n", n)
	}
	if n := p.ConflictsRR; n != 0 {
		fmt.Fprintf(os.Stderr, "conflicts: %d reduce/reduce\n", n)
	}

	f.Format(`%u)

var %[1]sDebug = 0

type %[1]sLexer interface {
	Lex(lval *%[1]sSymType) int
	Errorf(format string, a ...interface{})
	Errors() []error
}

type %[1]sLexerEx interface {
	%[1]sLexer
	Reduced(rule, state int, lval *%[1]sSymType) bool
}

func %[1]sSymName(c int) (s string) {
	x, ok := %[1]sXLAT[c]
	if ok {
		return %[1]sSymNames[x]
	}

	return __yyfmt__.Sprintf("%%d", c)
}

func %[1]slex1(yylex %[1]sLexer, lval *%[1]sSymType) (n int) {
	n = yylex.Lex(lval)
	if n <= 0 {
		n = %[1]sEofCode
	}
	if %[1]sDebug >= 3 {
		__yyfmt__.Printf("\nlex %%s(%%#x %%d), %[4]s: %[3]s\n", %[1]sSymName(n), n, n, %[4]s)
	}
	return n
}

func %[1]sParse(yylex %[1]sLexer, parser *Parser) int {
	const yyError = %[2]d

	yyEx, _ := yylex.(%[1]sLexerEx)
	var yyn int
	parser.yylval = %[1]sSymType{}
	parser.yyVAL = %[1]sSymType{}
	yyS := parser.cache

	Nerrs := 0   /* number of errors */
	Errflag := 0 /* error recovery flag */
	yyerrok := func() { 
		if %[1]sDebug >= 2 {
			__yyfmt__.Printf("yyerrok()\n")
		}
		Errflag = 0
	}
	_ = yyerrok
	yystate := 0
	yychar := -1
	var yyxchar int
	var yyshift int
	yyp := -1
	goto yystack

ret0:
	return 0

ret1:
	return 1

yystack:
	/* put a state and value onto the stack */
	yyp++
	if yyp >= len(yyS) {
		nyys := make([]%[1]sSymType, len(yyS)*2)
		copy(nyys, yyS)
		yyS = nyys
		parser.cache = yyS
	}
	yyS[yyp] = parser.yyVAL
	yyS[yyp].yys = yystate

yynewstate:
	if yychar < 0 {
		yychar = %[1]slex1(yylex, &parser.yylval)
		var ok bool
		if yyxchar, ok = %[1]sXLAT[yychar]; !ok {
			yyxchar = len(%[1]sSymNames) // > tab width
		}
	}
	if %[1]sDebug >= 4 {
		var a []int
		for _, v := range yyS[:yyp+1] {
			a = append(a, v.yys)
		}
		__yyfmt__.Printf("state stack %%v\n", a)
	}
	row := %[1]sParseTab[yystate]
	yyn = 0
	if yyxchar < len(row) {
		if yyn = int(row[yyxchar]); yyn != 0 {
			yyn += %[1]sTabOfs
		}
	}
	switch {
	case yyn > 0: // shift
		yychar = -1
		parser.yyVAL = parser.yylval
		yystate = yyn
		yyshift = yyn
		if %[1]sDebug >= 2 {
			__yyfmt__.Printf("shift, and goto state %%d\n", yystate)
		}
		if Errflag > 0 {
			Errflag--
		}
		goto yystack
	case yyn < 0: // reduce
	case yystate == 1: // accept
		if %[1]sDebug >= 2 {
			__yyfmt__.Println("accept")
		}
		goto ret0
	}

	if yyn == 0 {
		/* error ... attempt to resume parsing */
		switch Errflag {
		case 0: /* brand new error */
			if %[1]sDebug >= 1 {
				__yyfmt__.Printf("no action for %%s in state %%d\n", %[1]sSymName(yychar), yystate)
			}
			msg, ok := %[1]sXErrors[%[1]sXError{yystate, yyxchar}]
			if !ok {
				msg, ok = %[1]sXErrors[%[1]sXError{yystate, -1}]
			}
			if !ok && yyshift != 0 {
				msg, ok = %[1]sXErrors[%[1]sXError{yyshift, yyxchar}]
			}
			if !ok {
				msg, ok = %[1]sXErrors[%[1]sXError{yyshift, -1}]
			}
			if !ok || msg == "" {
				msg = "syntax error"
			}
			// ignore goyacc error message
			yylex.Errorf("")
			Nerrs++
			fallthrough

		case 1, 2: /* incompletely recovered error ... try again */
			Errflag = 3

			/* find a state where "error" is a legal shift action */
			for yyp >= 0 {
				row := %[1]sParseTab[yyS[yyp].yys]
				if yyError < len(row) {
					yyn = int(row[yyError])+%[1]sTabOfs
					if yyn > 0 { // hit
						if %[1]sDebug >= 2 {
							__yyfmt__.Printf("error recovery found error shift in state %%d\n", yyS[yyp].yys)
						}
						yystate = yyn /* simulate a shift of "error" */
						goto yystack
					}
				}

				/* the current p has no shift on "error", pop stack */
				if %[1]sDebug >= 2 {
					__yyfmt__.Printf("error recovery pops state %%d\n", yyS[yyp].yys)
				}
				yyp--
			}
			/* there is no state on the stack with an error shift ... abort */
			if %[1]sDebug >= 2 {
				__yyfmt__.Printf("error recovery failed\n")
			}
			goto ret1

		case 3: /* no shift yet; clobber input char */
			if %[1]sDebug >= 2 {
				__yyfmt__.Printf("error recovery discards %%s\n", %[1]sSymName(yychar))
			}
			if yychar == %[1]sEofCode {
				goto ret1
			}

			yychar = -1
			goto yynewstate /* try again in the same state */
		}
	}

	r := -yyn
	x0 := %[1]sReductions[r]
	x, n := x0.xsym, x0.components
	yypt := yyp
	_ = yypt // guard against "declared and not used"

	yyp -= n
	if yyp+1 >= len(yyS) {
		nyys := make([]%[1]sSymType, len(yyS)*2)
		copy(nyys, yyS)
		yyS = nyys
		parser.cache = yyS
	}
	parser.yyVAL = yyS[yyp+1]

	/* consult goto table to find next state */
	exState := yystate
	yystate = int(%[1]sParseTab[yyS[yyp].yys][x])+%[1]sTabOfs
	/* reduction by production r */
	if %[1]sDebug >= 2 {
		__yyfmt__.Printf("reduce using rule %%v (%%s), and goto state %%d\n", r, %[1]sSymNames[x], yystate)
	}

	switch r {%i
`,
		*oPref, errSym, *oDlvalf, *oDlval)
	for r, rule := range p.Rules {
		if rule.Action == nil {
			continue
		}

		action := rule.Action.Values
		if len(action) == 0 {
			continue
		}

		if len(action) == 1 {
			part := action[0]
			if part.Type == parser.ActionValueGo {
				src := part.Src
				src = src[1 : len(src)-1] // Remove lead '{' and trail '}'
				if strings.TrimSpace(src) == "" {
					continue
				}
			}
		}

		components := rule.Components
		typ := rule.Sym.Type
		max := len(components)
		if p1 := rule.Parent; p1 != nil {
			max = rule.MaxParentDlr
			components = p1.Components
		}
		f.Format("case %d: ", r)
		for _, part := range action {
			num := part.Num
			switch part.Type {
			case parser.ActionValueGo:
				f.Format("%s", part.Src)
			case parser.ActionValueDlrDlr:
				f.Format("parser.yyVAL.%s", typ)
				if typ == "" {
					panic("internal error 002")
				}
			case parser.ActionValueDlrNum:
				typ := p.Syms[components[num-1]].Type
				if typ == "" {
					panic("internal error 003")
				}
				f.Format("yyS[yypt-%d].%s", max-num, typ)
			case parser.ActionValueDlrTagDlr:
				f.Format("parser.yyVAL.%s", part.Tag)
			case parser.ActionValueDlrTagNum:
				f.Format("yyS[yypt-%d].%s", max-num, part.Tag)
			}
		}
		f.Format("\n")
	}
	f.Format(`%u
	}

	if yyEx != nil && yyEx.Reduced(r, exState, &parser.yyVAL) {
		return -1
	}
	goto yystack /* stack new state and value */
}

%[2]s
`, *oPref, p.Tail)
	_ = oNoLines //TODO Ignored for now
	return nil
}
コード例 #2
0
ファイル: main.go プロジェクト: cznic/yy
func main() {
	log.SetFlags(0)
	flag.Parse()
	checkOptions()

	var rep io.Writer
	if nm := *oReport; nm != "" {
		f, err := os.Create(nm)
		if err != nil {
			log.Fatal(err)
		}

		defer f.Close()

		w := bufio.NewWriter(f)

		defer w.Flush()

		rep = w
	}

	fset = token.NewFileSet()
	spec, err := y.ProcessFile(fset, flag.Arg(0), &y.Options{
		AllowTypeErrors: true,
		Closures:        true,
		Report:          rep,
	})
	if err != nil {
		log.Fatal(err)
	}

	if *oPkg == "" {
		s := extractPkg(spec.Prologue)
		if s == "" {
			s = "main"
		}
		*oPkg = s
	}
	copyright = extractCopyright(spec.Prologue)
	union := spec.Union
	if union == nil {
		log.Fatal("missing %union definition")
	}

	for _, fields := range union.Fields.List[1:] { // Skip yys int.
		for _, nm := range fields.Names {
			ytypes[nm.Name] = astString(fields.Type)
		}
	}

	if _, ok := ytypes[*oNode]; !ok {
		log.Fatalf("undefined yacc type: %s", *oNode)
	}

	if _, ok := ytypes[*oToken]; !ok {
		log.Fatalf("undefined yacc type: %s", *oToken)
	}

	var a []string
	for _, sym := range spec.Syms {
		switch {
		case sym.IsTerminal:
			s := sym.Name
			s0 := s[0]
			if s == "error" || s0 > 0x7f || s0 == '#' || s0 == '$' {
				continue
			}

			a = append(a, sym.Name)
		default:
			if sym.Name[0] == '$' {
				break
			}

			a = append(a, sym.Name)
			for i, v := range sym.Rules {
				kind[v] = i
			}
		}
	}
	sort.Strings(a)
	for _, nm := range a {
		sym := spec.Syms[nm]
		if sym.IsTerminal {
			terminals = append(terminals, sym)
			continue
		}
		nonTerminals = append(nonTerminals, sym)
	}

	checkDirectives(spec)
	nspec := genY(spec)
	genAST(spec)
	if *oASTExamples == os.DevNull {
		return
	}

	genASTExamples(nspec)
}