Commit 418b97c6 authored by Rob Pike's avatar Rob Pike

add printf to fmt.

uses reflection to determine arguments.
for now, the arguments must be provided as a struct; the compiler
will soon do the packaging automatically for "..." parameters.

R=rsc
DELTA=1436  (909 added, 520 deleted, 7 changed)
OCL=17823
CL=17831
parent 689b28fd
......@@ -3,7 +3,7 @@
# license that can be found in the LICENSE file.
# DO NOT EDIT. Automatically generated by gobuild.
# gobuild -m fmt fmt.go
# gobuild -m fmt format.go print.go
O=6
GC=$(O)g
CC=$(O)c -w
......@@ -31,11 +31,17 @@ clean:
O1=\
fmt.$O\
format.$O\
$(PKG): a1
O2=\
print.$O\
$(PKG): a1 a2
a1: $(O1)
$(AR) grc $(PKG) $(O1)
a2: $(O2)
$(AR) grc $(PKG) $(O2)
$(O1): nuke
$(O2): a1
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package fmt
import (
"fmt";
"reflect";
"os";
)
const Runeself = 0x80
const AllocSize = 32
export type P struct {
n int;
buf *[]byte;
fmt *Fmt;
}
export func Printer() *P {
p := new(P);
p.fmt = fmt.New();
return p;
}
func (p *P) ensure(n int) {
if p.buf == nil || len(p.buf) < n {
newn := AllocSize;
if p.buf != nil {
newn += len(p.buf);
}
if newn < n {
newn = n + AllocSize
}
b := new([]byte, newn);
for i := 0; i < p.n; i++ {
b[i] = p.buf[i];
}
p.buf = b;
}
}
func (p *P) addstr(s string) {
n := len(s);
p.ensure(p.n + n);
for i := 0; i < n; i++ {
p.buf[p.n] = s[i];
p.n++;
}
}
func (p *P) addbytes(b *[]byte, start, end int) {
p.ensure(p.n + end-start);
for i := start; i < end; i++ {
p.buf[p.n] = b[i];
p.n++;
}
}
func (p *P) add(c int) {
p.ensure(p.n + 1);
if c < Runeself {
p.buf[p.n] = byte(c);
p.n++;
} else {
p.addstr(string(c));
}
}
func (p *P) reset() {
p.n = 0;
}
export type Writer interface {
Write(b *[]byte) (ret int, err *os.Error);
}
func (p *P) doprintf(format string, v reflect.StructValue);
func (p *P) doprint(v reflect.StructValue, addspace bool);
// These routines end in 'f' and take a format string.
func (p *P) fprintf(w Writer, format string, a reflect.Empty) (n int, error *os.Error) {
v := reflect.NewValue(a).(reflect.PtrValue).Sub().(reflect.StructValue);
p.doprintf(format, v);
n, error = w.Write(p.buf[0:p.n]);
p.reset();
return n, error;
}
func (p *P) printf(format string, v reflect.Empty) (n int, errno *os.Error) {
n, errno = p.fprintf(os.Stdout, format, v);
return n, errno;
}
func (p *P) sprintf(format string, v reflect.Empty) string {
p.doprintf(format, reflect.NewValue(v).(reflect.StructValue));
s := string(p.buf)[0 : p.n];
p.reset();
return s;
}
// These routines do not take a format string and add spaces only
// when the operand on neither side is a string.
func (p *P) fprint(w Writer, a reflect.Empty) (n int, error *os.Error) {
v := reflect.NewValue(a).(reflect.PtrValue).Sub().(reflect.StructValue);
p.doprint(v, false);
n, error = w.Write(p.buf[0:p.n]);
p.reset();
return n, error;
}
func (p *P) print(v reflect.Empty) (n int, errno *os.Error) {
n, errno = p.fprint(os.Stdout, v);
return n, errno;
}
func (p *P) sprint(v reflect.Empty) string {
p.doprint(reflect.NewValue(v).(reflect.StructValue), false);
s := string(p.buf)[0 : p.n];
p.reset();
return s;
}
// These routines end in 'ln', do not take a format string,
// always add spaces between operands, and add a newline
// after the last operand.
func (p *P) fprintln(w Writer, a reflect.Empty) (n int, error *os.Error) {
v := reflect.NewValue(a).(reflect.PtrValue).Sub().(reflect.StructValue);
p.doprint(v, true);
n, error = w.Write(p.buf[0:p.n]);
p.reset();
return n, error;
}
func (p *P) println(v reflect.Empty) (n int, errno *os.Error) {
n, errno = p.fprintln(os.Stdout, v);
return n, errno;
}
func (p *P) sprintln(v reflect.Empty) string {
p.doprint(reflect.NewValue(v).(reflect.StructValue), true);
s := string(p.buf)[0 : p.n];
p.reset();
return s;
}
// Getters for the fields of the argument structure.
func getInt(v reflect.Value) (val int64, signed, ok bool) {
switch v.Kind() {
case reflect.Int8Kind:
return int64(v.(reflect.Int8Value).Get()), true, true;
case reflect.Int16Kind:
return int64(v.(reflect.Int16Value).Get()), true, true;
case reflect.Int32Kind:
return int64(v.(reflect.Int32Value).Get()), true, true;
case reflect.Int64Kind:
return int64(v.(reflect.Int64Value).Get()), true, true;
case reflect.Uint8Kind:
return int64(v.(reflect.Uint8Value).Get()), false, true;
case reflect.Uint16Kind:
return int64(v.(reflect.Uint16Value).Get()), false, true;
case reflect.Uint32Kind:
return int64(v.(reflect.Uint32Value).Get()), false, true;
case reflect.Uint64Kind:
return int64(v.(reflect.Uint64Value).Get()), false, true;
}
return 0, false, false;
}
func getString(v reflect.Value) (val string, ok bool) {
switch v.Kind() {
case reflect.StringKind:
return v.(reflect.StringValue).Get(), true;
}
return "", false;
}
func getFloat(v reflect.Value) (val float64, ok bool) {
switch v.Kind() {
case reflect.Float32Kind:
return float64(v.(reflect.Float32Value).Get()), true;
case reflect.Float64Kind:
return float64(v.(reflect.Float32Value).Get()), true;
case reflect.Float80Kind:
break; // TODO: what to do here?
}
return 0.0, false;
}
func getPtr(v reflect.Value) (val uint64, ok bool) {
switch v.Kind() {
case reflect.PtrKind:
return v.(reflect.PtrValue).Get(), true;
}
return 0, false;
}
// Convert ASCII to integer.
func parsenum(s string, start, end int) (n int, got bool, newi int) {
if start >= end {
return 0, false, end
}
if s[start] == '-' {
a, b, c := parsenum(s, start+1, end);
if b {
return -a, b, c;
}
}
isnum := false;
num := 0;
for '0' <= s[start] && s[start] <= '9' {
num = num*10 + int(s[start] - '0');
start++;
isnum = true;
}
return num, isnum, start;
}
func (p *P) doprintf(format string, v reflect.StructValue) {
p.ensure(len(format)); // a good starting size
end := len(format) - 1;
fieldnum := 0; // we process one field per non-trivial format
for i := 0; i <= end; {
c, w := sys.stringtorune(format, i);
if c != '%' || i == end {
p.add(c);
i += w;
continue;
}
var got bool;
// saw % - do we have %20 (width)?
w, got, i = parsenum(format, i+1, end);
if got {
p.fmt.w(w);
}
// do we have %.20 (precision)?
if i < end && format[i] == '.' {
w, got, i = parsenum(format, i+1, end);
if got {
p.fmt.p(w);
}
}
c, w = sys.stringtorune(format, i);
i += w;
// percent is special - absorbs no operand
if c == '%' {
p.add('%'); // TODO: should we bother with width & prec?
continue;
}
if fieldnum >= v.Len() { // out of operands
p.addstr("???");
continue;
}
field := v.Field(fieldnum);
fieldnum++;
s := "";
switch c {
// int
case 'b':
if v, signed, ok := getInt(field); ok {
s = p.fmt.B(v).str() // always unsigned
} else {
s = "%b%"
}
case 'd':
if v, signed, ok := getInt(field); ok {
if signed {
s = p.fmt.D(v).str()
} else {
s = p.fmt.uD(v).str()
}
} else {
s = "%d%"
}
case 'o':
if v, signed, ok := getInt(field); ok {
if signed {
s = p.fmt.O(v).str()
} else {
s = p.fmt.uO(v).str()
}
} else {
s= "%o%"
}
case 'x':
if v, signed, ok := getInt(field); ok {
if signed {
s = p.fmt.X(v).str()
} else {
s = p.fmt.uX(v).str()
}
} else {
s = "%x%"
}
// float
case 'e':
if v, ok := getFloat(field); ok {
s = p.fmt.E(v).str()
} else {
s = "%e%"
}
case 'f':
if v, ok := getFloat(field); ok {
s = p.fmt.F(v).str()
} else {
s = "%f%";
}
case 'g':
if v, ok := getFloat(field); ok {
s = p.fmt.G(v).str()
} else {
s = "%g%"
}
// string
case 's':
if v, ok := getString(field); ok {
s = p.fmt.s(v).str()
} else {
s = "%s%"
}
// pointer
case 'p':
if v, ok := getPtr(field); ok {
s = "0x" + p.fmt.uX(int64(v)).str()
} else {
s = "%p%"
}
default:
s = "?" + string(c) + "?";
}
p.addstr(s);
}
}
func (p *P) doprint(v reflect.StructValue, is_println bool) {
prev_string := false;
for fieldnum := 0; fieldnum < v.Len(); fieldnum++ {
// always add spaces if we're doing println
field := v.Field(fieldnum);
s := "";
if is_println {
if fieldnum > 0 {
p.add(' ')
}
} else if field.Kind() != reflect.StringKind && !prev_string{
// if not doing println, add spaces if neither side is a string
p.add(' ')
}
switch field.Kind() {
case reflect.Int8Kind, reflect.Int16Kind, reflect.Int32Kind, reflect.Int64Kind:
v, signed, ok := getInt(field);
s = p.fmt.D(v).str();
case reflect.Uint8Kind, reflect.Uint16Kind, reflect.Uint32Kind, reflect.Uint64Kind:
v, signed, ok := getInt(field);
s = p.fmt.uD(v).str();
case reflect.Float32Kind, reflect.Float64Kind, reflect.Float80Kind:
v, ok := getFloat(field);
s = p.fmt.G(v).str();
case reflect.StringKind:
v, ok := getString(field);
s = p.fmt.s(v).str();
case reflect.PtrKind:
v, ok := getPtr(field);
p.add('0');
p.add('x');
s = p.fmt.uX(int64(v)).str();
default:
s = "???";
}
p.addstr(s);
prev_string = field.Kind() == reflect.StringKind;
}
if is_println {
p.add('\n')
}
}
......@@ -151,7 +151,7 @@ func ValueToString(val Value) string {
return val.(StringValue).Get();
case PtrKind:
v := val.(PtrValue);
return TypeToString(typ, false) + "(" + integer(int64(v.Indirect())) + ")";
return TypeToString(typ, false) + "(" + integer(int64(v.Get())) + ")";
case ArrayKind:
t := typ.(ArrayType);
v := val.(ArrayValue);
......
......@@ -444,9 +444,9 @@ func (v *StringValueStruct) Put(s string) {
export type PtrValue interface {
Kind() int;
Sub() Value;
Type() Type;
Indirect() Addr;
Sub() Value;
Get() Addr;
}
type PtrValueStruct struct {
......@@ -462,12 +462,12 @@ func (v *PtrValueStruct) Type() Type {
return v.typ
}
func (v *PtrValueStruct) Indirect() Addr {
func (v *PtrValueStruct) Get() Addr {
return *AddrToPtrAddr(v.addr)
}
func (v *PtrValueStruct) Sub() Value {
return NewValueAddr(v.typ.(PtrType).Sub(), v.Indirect());
return NewValueAddr(v.typ.(PtrType).Sub(), v.Get());
}
func PtrCreator(typ Type, addr Addr) Value {
......
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