[dev.cc] cmd/internal/gc, cmd/new6g etc: convert from cmd/gc, cmd/6g etc

First draft of converted Go compiler, using rsc.io/c2go rev 83d795a.

Change-Id: I29f4c7010de07d2ff1947bbca9865879d83c32c3
Reviewed-on: https://go-review.googlesource.com/4851
Reviewed-by: Rob Pike <r@golang.org>

src/cmd/internal/obj/util.go

@@ -8,6 +8,7 @@ import (
 	"bufio"
 	"fmt"
 	"io"
+	"log"
 	"os"
 	"strconv"
 	"time"
@@ -23,21 +24,30 @@ func Cputime() float64 {
 }
 
 type Biobuf struct {
-	unget     int
-	haveUnget bool
-	f         *os.File
-	r         *bufio.Reader
-	w         *bufio.Writer
+	unget    [2]int
+	numUnget int
+	f        *os.File
+	r        *bufio.Reader
+	w        *bufio.Writer
+	linelen  int
 }
 
 func Bopenw(name string) (*Biobuf, error) {
-	f, err := os.Open(name)
+	f, err := os.Create(name)
 	if err != nil {
 		return nil, err
 	}
 	return &Biobuf{f: f, w: bufio.NewWriter(f)}, nil
 }
 
+func Bopenr(name string) (*Biobuf, error) {
+	f, err := os.Open(name)
+	if err != nil {
+		return nil, err
+	}
+	return &Biobuf{f: f, r: bufio.NewReader(f)}, nil
+}
+
 func Binitw(w io.Writer) *Biobuf {
 	return &Biobuf{w: bufio.NewWriter(w)}
 }
@@ -46,6 +56,41 @@ func (b *Biobuf) Write(p []byte) (int, error) {
 	return b.w.Write(p)
 }
 
+func Bwritestring(b *Biobuf, p string) (int, error) {
+	return b.w.WriteString(p)
+}
+
+func Bseek(b *Biobuf, offset int64, whence int) int64 {
+	if b.w != nil {
+		if err := b.w.Flush(); err != nil {
+			log.Fatal("writing output: %v", err)
+		}
+	} else if b.r != nil {
+		if whence == 1 {
+			offset -= int64(b.r.Buffered())
+		}
+	}
+	off, err := b.f.Seek(offset, whence)
+	if err != nil {
+		log.Fatal("seeking in output: %v", err)
+	}
+	if b.r != nil {
+		b.r.Reset(b.f)
+	}
+	return off
+}
+
+func Boffset(b *Biobuf) int64 {
+	if err := b.w.Flush(); err != nil {
+		log.Fatal("writing output: %v", err)
+	}
+	off, err := b.f.Seek(0, 1)
+	if err != nil {
+		log.Fatal("seeking in output: %v", err)
+	}
+	return off
+}
+
 func (b *Biobuf) Flush() error {
 	return b.w.Flush()
 }
@@ -58,26 +103,86 @@ func Bputc(b *Biobuf, c byte) {
 	b.w.WriteByte(c)
 }
 
+const Beof = -1
+
+func Bread(b *Biobuf, p []byte) int {
+	n, err := io.ReadFull(b.r, p)
+	if n == 0 {
+		if err != nil && err != io.EOF {
+			n = -1
+		}
+	}
+	return n
+}
+
 func Bgetc(b *Biobuf) int {
-	if b.haveUnget {
-		b.haveUnget = false
-		return int(b.unget)
+	if b.numUnget > 0 {
+		b.numUnget--
+		return int(b.unget[b.numUnget])
 	}
 	c, err := b.r.ReadByte()
+	r := int(c)
+	if err != nil {
+		r = -1
+	}
+	b.unget[1] = b.unget[0]
+	b.unget[0] = r
+	return r
+}
+
+func Bgetrune(b *Biobuf) int {
+	r, _, err := b.r.ReadRune()
 	if err != nil {
-		b.unget = -1
 		return -1
 	}
-	b.unget = int(c)
-	return int(c)
+	return int(r)
+}
+
+func Bungetrune(b *Biobuf) {
+	b.r.UnreadRune()
+}
+
+func (b *Biobuf) Read(p []byte) (int, error) {
+	return b.r.Read(p)
+}
+
+func Brdline(b *Biobuf, delim int) string {
+	s, err := b.r.ReadBytes(byte(delim))
+	if err != nil {
+		log.Fatalf("reading input: %v", err)
+	}
+	b.linelen = len(s)
+	return string(s)
+}
+
+func Brdstr(b *Biobuf, delim int, cut int) string {
+	s, err := b.r.ReadString(byte(delim))
+	if err != nil {
+		log.Fatalf("reading input: %v", err)
+	}
+	if len(s) > 0 && cut > 0 {
+		s = s[:len(s)-1]
+	}
+	return s
+}
+
+func Access(name string, mode int) int {
+	if mode != 0 {
+		panic("bad access")
+	}
+	_, err := os.Stat(name)
+	if err != nil {
+		return -1
+	}
+	return 0
+}
+
+func Blinelen(b *Biobuf) int {
+	return b.linelen
 }
 
 func Bungetc(b *Biobuf) {
-	b.haveUnget = true
-}
-
-func Boffset(b *Biobuf) int64 {
-	panic("Boffset")
+	b.numUnget++
 }
 
 func Bflush(b *Biobuf) error {
@@ -85,7 +190,10 @@ func Bflush(b *Biobuf) error {
 }
 
 func Bterm(b *Biobuf) error {
-	err := b.w.Flush()
+	var err error
+	if b.w != nil {
+		err = b.w.Flush()
+	}
 	err1 := b.f.Close()
 	if err == nil {
 		err = err1
@@ -116,6 +224,10 @@ func Getgoarm() string {
 	return envOr("GOARM", defaultGOARM)
 }
 
+func Getgo386() string {
+	return envOr("GO386", defaultGO386)
+}
+
 func Getgoversion() string {
 	return version
 }
@@ -145,3 +257,15 @@ func (ctxt *Link) NewProg() *Prog {
 func (ctxt *Link) Line(n int) string {
 	return Linklinefmt(ctxt, n, false, false)
 }
+
+func (ctxt *Link) Dconv(a *Addr) string {
+	return ctxt.Arch.Dconv(nil, 0, a)
+}
+
+func (ctxt *Link) Rconv(reg int) string {
+	return ctxt.Arch.Rconv(reg)
+}
+
+func Getcallerpc(interface{}) uintptr {
+	return 1
+}