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[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [libgo/] [go/] [encoding/] [asn1/] [marshal.go] - Blame information for rev 774

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// 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 asn1
 
import (
        "bytes"
        "fmt"
        "io"
        "math/big"
        "reflect"
        "time"
)
 
// A forkableWriter is an in-memory buffer that can be
// 'forked' to create new forkableWriters that bracket the
// original.  After
//    pre, post := w.fork();
// the overall sequence of bytes represented is logically w+pre+post.
type forkableWriter struct {
        *bytes.Buffer
        pre, post *forkableWriter
}
 
func newForkableWriter() *forkableWriter {
        return &forkableWriter{new(bytes.Buffer), nil, nil}
}
 
func (f *forkableWriter) fork() (pre, post *forkableWriter) {
        if f.pre != nil || f.post != nil {
                panic("have already forked")
        }
        f.pre = newForkableWriter()
        f.post = newForkableWriter()
        return f.pre, f.post
}
 
func (f *forkableWriter) Len() (l int) {
        l += f.Buffer.Len()
        if f.pre != nil {
                l += f.pre.Len()
        }
        if f.post != nil {
                l += f.post.Len()
        }
        return
}
 
func (f *forkableWriter) writeTo(out io.Writer) (n int, err error) {
        n, err = out.Write(f.Bytes())
        if err != nil {
                return
        }
 
        var nn int
 
        if f.pre != nil {
                nn, err = f.pre.writeTo(out)
                n += nn
                if err != nil {
                        return
                }
        }
 
        if f.post != nil {
                nn, err = f.post.writeTo(out)
                n += nn
        }
        return
}
 
func marshalBase128Int(out *forkableWriter, n int64) (err error) {
        if n == 0 {
                err = out.WriteByte(0)
                return
        }
 
        l := 0
        for i := n; i > 0; i >>= 7 {
                l++
        }
 
        for i := l - 1; i >= 0; i-- {
                o := byte(n >> uint(i*7))
                o &= 0x7f
                if i != 0 {
                        o |= 0x80
                }
                err = out.WriteByte(o)
                if err != nil {
                        return
                }
        }
 
        return nil
}
 
func marshalInt64(out *forkableWriter, i int64) (err error) {
        n := int64Length(i)
 
        for ; n > 0; n-- {
                err = out.WriteByte(byte(i >> uint((n-1)*8)))
                if err != nil {
                        return
                }
        }
 
        return nil
}
 
func int64Length(i int64) (numBytes int) {
        numBytes = 1
 
        for i > 127 {
                numBytes++
                i >>= 8
        }
 
        for i < -128 {
                numBytes++
                i >>= 8
        }
 
        return
}
 
func marshalBigInt(out *forkableWriter, n *big.Int) (err error) {
        if n.Sign() < 0 {
                // A negative number has to be converted to two's-complement
                // form. So we'll subtract 1 and invert. If the
                // most-significant-bit isn't set then we'll need to pad the
                // beginning with 0xff in order to keep the number negative.
                nMinus1 := new(big.Int).Neg(n)
                nMinus1.Sub(nMinus1, bigOne)
                bytes := nMinus1.Bytes()
                for i := range bytes {
                        bytes[i] ^= 0xff
                }
                if len(bytes) == 0 || bytes[0]&0x80 == 0 {
                        err = out.WriteByte(0xff)
                        if err != nil {
                                return
                        }
                }
                _, err = out.Write(bytes)
        } else if n.Sign() == 0 {
                // Zero is written as a single 0 zero rather than no bytes.
                err = out.WriteByte(0x00)
        } else {
                bytes := n.Bytes()
                if len(bytes) > 0 && bytes[0]&0x80 != 0 {
                        // We'll have to pad this with 0x00 in order to stop it
                        // looking like a negative number.
                        err = out.WriteByte(0)
                        if err != nil {
                                return
                        }
                }
                _, err = out.Write(bytes)
        }
        return
}
 
func marshalLength(out *forkableWriter, i int) (err error) {
        n := lengthLength(i)
 
        for ; n > 0; n-- {
                err = out.WriteByte(byte(i >> uint((n-1)*8)))
                if err != nil {
                        return
                }
        }
 
        return nil
}
 
func lengthLength(i int) (numBytes int) {
        numBytes = 1
        for i > 255 {
                numBytes++
                i >>= 8
        }
        return
}
 
func marshalTagAndLength(out *forkableWriter, t tagAndLength) (err error) {
        b := uint8(t.class) << 6
        if t.isCompound {
                b |= 0x20
        }
        if t.tag >= 31 {
                b |= 0x1f
                err = out.WriteByte(b)
                if err != nil {
                        return
                }
                err = marshalBase128Int(out, int64(t.tag))
                if err != nil {
                        return
                }
        } else {
                b |= uint8(t.tag)
                err = out.WriteByte(b)
                if err != nil {
                        return
                }
        }
 
        if t.length >= 128 {
                l := lengthLength(t.length)
                err = out.WriteByte(0x80 | byte(l))
                if err != nil {
                        return
                }
                err = marshalLength(out, t.length)
                if err != nil {
                        return
                }
        } else {
                err = out.WriteByte(byte(t.length))
                if err != nil {
                        return
                }
        }
 
        return nil
}
 
func marshalBitString(out *forkableWriter, b BitString) (err error) {
        paddingBits := byte((8 - b.BitLength%8) % 8)
        err = out.WriteByte(paddingBits)
        if err != nil {
                return
        }
        _, err = out.Write(b.Bytes)
        return
}
 
func marshalObjectIdentifier(out *forkableWriter, oid []int) (err error) {
        if len(oid) < 2 || oid[0] > 6 || oid[1] >= 40 {
                return StructuralError{"invalid object identifier"}
        }
 
        err = out.WriteByte(byte(oid[0]*40 + oid[1]))
        if err != nil {
                return
        }
        for i := 2; i < len(oid); i++ {
                err = marshalBase128Int(out, int64(oid[i]))
                if err != nil {
                        return
                }
        }
 
        return
}
 
func marshalPrintableString(out *forkableWriter, s string) (err error) {
        b := []byte(s)
        for _, c := range b {
                if !isPrintable(c) {
                        return StructuralError{"PrintableString contains invalid character"}
                }
        }
 
        _, err = out.Write(b)
        return
}
 
func marshalIA5String(out *forkableWriter, s string) (err error) {
        b := []byte(s)
        for _, c := range b {
                if c > 127 {
                        return StructuralError{"IA5String contains invalid character"}
                }
        }
 
        _, err = out.Write(b)
        return
}
 
func marshalTwoDigits(out *forkableWriter, v int) (err error) {
        err = out.WriteByte(byte('0' + (v/10)%10))
        if err != nil {
                return
        }
        return out.WriteByte(byte('0' + v%10))
}
 
func marshalUTCTime(out *forkableWriter, t time.Time) (err error) {
        utc := t.UTC()
        year, month, day := utc.Date()
 
        switch {
        case 1950 <= year && year < 2000:
                err = marshalTwoDigits(out, int(year-1900))
        case 2000 <= year && year < 2050:
                err = marshalTwoDigits(out, int(year-2000))
        default:
                return StructuralError{"Cannot represent time as UTCTime"}
        }
        if err != nil {
                return
        }
 
        err = marshalTwoDigits(out, int(month))
        if err != nil {
                return
        }
 
        err = marshalTwoDigits(out, day)
        if err != nil {
                return
        }
 
        hour, min, sec := utc.Clock()
 
        err = marshalTwoDigits(out, hour)
        if err != nil {
                return
        }
 
        err = marshalTwoDigits(out, min)
        if err != nil {
                return
        }
 
        err = marshalTwoDigits(out, sec)
        if err != nil {
                return
        }
 
        _, offset := t.Zone()
 
        switch {
        case offset/60 == 0:
                err = out.WriteByte('Z')
                return
        case offset > 0:
                err = out.WriteByte('+')
        case offset < 0:
                err = out.WriteByte('-')
        }
 
        if err != nil {
                return
        }
 
        offsetMinutes := offset / 60
        if offsetMinutes < 0 {
                offsetMinutes = -offsetMinutes
        }
 
        err = marshalTwoDigits(out, offsetMinutes/60)
        if err != nil {
                return
        }
 
        err = marshalTwoDigits(out, offsetMinutes%60)
        return
}
 
func stripTagAndLength(in []byte) []byte {
        _, offset, err := parseTagAndLength(in, 0)
        if err != nil {
                return in
        }
        return in[offset:]
}
 
func marshalBody(out *forkableWriter, value reflect.Value, params fieldParameters) (err error) {
        switch value.Type() {
        case timeType:
                return marshalUTCTime(out, value.Interface().(time.Time))
        case bitStringType:
                return marshalBitString(out, value.Interface().(BitString))
        case objectIdentifierType:
                return marshalObjectIdentifier(out, value.Interface().(ObjectIdentifier))
        case bigIntType:
                return marshalBigInt(out, value.Interface().(*big.Int))
        }
 
        switch v := value; v.Kind() {
        case reflect.Bool:
                if v.Bool() {
                        return out.WriteByte(255)
                } else {
                        return out.WriteByte(0)
                }
        case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
                return marshalInt64(out, int64(v.Int()))
        case reflect.Struct:
                t := v.Type()
 
                startingField := 0
 
                // If the first element of the structure is a non-empty
                // RawContents, then we don't bother serializing the rest.
                if t.NumField() > 0 && t.Field(0).Type == rawContentsType {
                        s := v.Field(0)
                        if s.Len() > 0 {
                                bytes := make([]byte, s.Len())
                                for i := 0; i < s.Len(); i++ {
                                        bytes[i] = uint8(s.Index(i).Uint())
                                }
                                /* The RawContents will contain the tag and
                                 * length fields but we'll also be writing
                                 * those ourselves, so we strip them out of
                                 * bytes */
                                _, err = out.Write(stripTagAndLength(bytes))
                                return
                        } else {
                                startingField = 1
                        }
                }
 
                for i := startingField; i < t.NumField(); i++ {
                        var pre *forkableWriter
                        pre, out = out.fork()
                        err = marshalField(pre, v.Field(i), parseFieldParameters(t.Field(i).Tag.Get("asn1")))
                        if err != nil {
                                return
                        }
                }
                return
        case reflect.Slice:
                sliceType := v.Type()
                if sliceType.Elem().Kind() == reflect.Uint8 {
                        bytes := make([]byte, v.Len())
                        for i := 0; i < v.Len(); i++ {
                                bytes[i] = uint8(v.Index(i).Uint())
                        }
                        _, err = out.Write(bytes)
                        return
                }
 
                var params fieldParameters
                for i := 0; i < v.Len(); i++ {
                        var pre *forkableWriter
                        pre, out = out.fork()
                        err = marshalField(pre, v.Index(i), params)
                        if err != nil {
                                return
                        }
                }
                return
        case reflect.String:
                if params.stringType == tagIA5String {
                        return marshalIA5String(out, v.String())
                } else {
                        return marshalPrintableString(out, v.String())
                }
                return
        }
 
        return StructuralError{"unknown Go type"}
}
 
func marshalField(out *forkableWriter, v reflect.Value, params fieldParameters) (err error) {
        // If the field is an interface{} then recurse into it.
        if v.Kind() == reflect.Interface && v.Type().NumMethod() == 0 {
                return marshalField(out, v.Elem(), params)
        }
 
        if params.optional && reflect.DeepEqual(v.Interface(), reflect.Zero(v.Type()).Interface()) {
                return
        }
 
        if v.Type() == rawValueType {
                rv := v.Interface().(RawValue)
                if len(rv.FullBytes) != 0 {
                        _, err = out.Write(rv.FullBytes)
                } else {
                        err = marshalTagAndLength(out, tagAndLength{rv.Class, rv.Tag, len(rv.Bytes), rv.IsCompound})
                        if err != nil {
                                return
                        }
                        _, err = out.Write(rv.Bytes)
                }
                return
        }
 
        tag, isCompound, ok := getUniversalType(v.Type())
        if !ok {
                err = StructuralError{fmt.Sprintf("unknown Go type: %v", v.Type())}
                return
        }
        class := classUniversal
 
        if params.stringType != 0 {
                if tag != tagPrintableString {
                        return StructuralError{"Explicit string type given to non-string member"}
                }
                tag = params.stringType
        }
 
        if params.set {
                if tag != tagSequence {
                        return StructuralError{"Non sequence tagged as set"}
                }
                tag = tagSet
        }
 
        tags, body := out.fork()
 
        err = marshalBody(body, v, params)
        if err != nil {
                return
        }
 
        bodyLen := body.Len()
 
        var explicitTag *forkableWriter
        if params.explicit {
                explicitTag, tags = tags.fork()
        }
 
        if !params.explicit && params.tag != nil {
                // implicit tag.
                tag = *params.tag
                class = classContextSpecific
        }
 
        err = marshalTagAndLength(tags, tagAndLength{class, tag, bodyLen, isCompound})
        if err != nil {
                return
        }
 
        if params.explicit {
                err = marshalTagAndLength(explicitTag, tagAndLength{
                        class:      classContextSpecific,
                        tag:        *params.tag,
                        length:     bodyLen + tags.Len(),
                        isCompound: true,
                })
        }
 
        return nil
}
 
// Marshal returns the ASN.1 encoding of val.
func Marshal(val interface{}) ([]byte, error) {
        var out bytes.Buffer
        v := reflect.ValueOf(val)
        f := newForkableWriter()
        err := marshalField(f, v, fieldParameters{})
        if err != nil {
                return nil, err
        }
        _, err = f.writeTo(&out)
        return out.Bytes(), nil
}

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[/] [openrisc/] [trunk/] [gnu-dev/] [or1k-gcc/] [libgo/] [go/] [encoding/] [asn1/] [marshal.go] - Blame information for rev 774

Line No.	Rev	Author	Line
1	747	jeremybenn	`// Copyright 2009 The Go Authors. All rights reserved.`
2			`// Use of this source code is governed by a BSD-style`
3			`// license that can be found in the LICENSE file.`
4
5			`package asn1`
6
7			`import (`
8			`"bytes"`
9			`"fmt"`
10			`"io"`
11			`"math/big"`
12			`"reflect"`
13			`"time"`
14			`)`
15
16			`// A forkableWriter is an in-memory buffer that can be`
17			`// 'forked' to create new forkableWriters that bracket the`
18			`// original. After`
19			`// pre, post := w.fork();`
20			`// the overall sequence of bytes represented is logically w+pre+post.`
21			`type forkableWriter struct {`
22			`*bytes.Buffer`
23			`pre, post *forkableWriter`
24			`}`
25
26			`func newForkableWriter() *forkableWriter {`
27			`return &forkableWriter{new(bytes.Buffer), nil, nil}`
28			`}`
29
30			`func (f forkableWriter) fork() (pre, post forkableWriter) {`
31			`if f.pre != nil \|\| f.post != nil {`
32			`panic("have already forked")`
33			`}`
34			`f.pre = newForkableWriter()`
35			`f.post = newForkableWriter()`
36			`return f.pre, f.post`
37			`}`
38
39			`func (f *forkableWriter) Len() (l int) {`
40			`l += f.Buffer.Len()`
41			`if f.pre != nil {`
42			`l += f.pre.Len()`
43			`}`
44			`if f.post != nil {`
45			`l += f.post.Len()`
46			`}`
47			`return`
48			`}`
49
50			`func (f *forkableWriter) writeTo(out io.Writer) (n int, err error) {`
51			`n, err = out.Write(f.Bytes())`
52			`if err != nil {`
53			`return`
54			`}`
55
56			`var nn int`
57
58			`if f.pre != nil {`
59			`nn, err = f.pre.writeTo(out)`
60			`n += nn`
61			`if err != nil {`
62			`return`
63			`}`
64			`}`
65
66			`if f.post != nil {`
67			`nn, err = f.post.writeTo(out)`
68			`n += nn`
69			`}`
70			`return`
71			`}`
72
73			`func marshalBase128Int(out *forkableWriter, n int64) (err error) {`
74			`if n == 0 {`
75			`err = out.WriteByte(0)`
76			`return`
77			`}`
78
79			`l := 0`
80			`for i := n; i > 0; i >>= 7 {`
81			`l++`
82			`}`
83
84			`for i := l - 1; i >= 0; i-- {`
85			`o := byte(n >> uint(i*7))`
86			`o &= 0x7f`
87			`if i != 0 {`
88			`o \|= 0x80`
89			`}`
90			`err = out.WriteByte(o)`
91			`if err != nil {`
92			`return`
93			`}`
94			`}`
95
96			`return nil`
97			`}`
98
99			`func marshalInt64(out *forkableWriter, i int64) (err error) {`
100			`n := int64Length(i)`
101
102			`for ; n > 0; n-- {`
103			`err = out.WriteByte(byte(i >> uint((n-1)*8)))`
104			`if err != nil {`
105			`return`
106			`}`
107			`}`
108
109			`return nil`
110			`}`
111
112			`func int64Length(i int64) (numBytes int) {`
113			`numBytes = 1`
114
115			`for i > 127 {`
116			`numBytes++`
117			`i >>= 8`
118			`}`
119
120			`for i < -128 {`
121			`numBytes++`
122			`i >>= 8`
123			`}`
124
125			`return`
126			`}`
127
128			`func marshalBigInt(out forkableWriter, n big.Int) (err error) {`
129			`if n.Sign() < 0 {`
130			`// A negative number has to be converted to two's-complement`
131			`// form. So we'll subtract 1 and invert. If the`
132			`// most-significant-bit isn't set then we'll need to pad the`
133			`// beginning with 0xff in order to keep the number negative.`
134			`nMinus1 := new(big.Int).Neg(n)`
135			`nMinus1.Sub(nMinus1, bigOne)`
136			`bytes := nMinus1.Bytes()`
137			`for i := range bytes {`
138			`bytes[i] ^= 0xff`
139			`}`
140			`if len(bytes) == 0 \|\| bytes[0]&0x80 == 0 {`
141			`err = out.WriteByte(0xff)`
142			`if err != nil {`
143			`return`
144			`}`
145			`}`
146			`_, err = out.Write(bytes)`
147			`} else if n.Sign() == 0 {`
148			`// Zero is written as a single 0 zero rather than no bytes.`
149			`err = out.WriteByte(0x00)`
150			`} else {`
151			`bytes := n.Bytes()`
152			`if len(bytes) > 0 && bytes[0]&0x80 != 0 {`
153			`// We'll have to pad this with 0x00 in order to stop it`
154			`// looking like a negative number.`
155			`err = out.WriteByte(0)`
156			`if err != nil {`
157			`return`
158			`}`
159			`}`
160			`_, err = out.Write(bytes)`
161			`}`
162			`return`
163			`}`
164
165			`func marshalLength(out *forkableWriter, i int) (err error) {`
166			`n := lengthLength(i)`
167
168			`for ; n > 0; n-- {`
169			`err = out.WriteByte(byte(i >> uint((n-1)*8)))`
170			`if err != nil {`
171			`return`
172			`}`
173			`}`
174
175			`return nil`
176			`}`
177
178			`func lengthLength(i int) (numBytes int) {`
179			`numBytes = 1`
180			`for i > 255 {`
181			`numBytes++`
182			`i >>= 8`
183			`}`
184			`return`
185			`}`
186
187			`func marshalTagAndLength(out *forkableWriter, t tagAndLength) (err error) {`
188			`b := uint8(t.class) << 6`
189			`if t.isCompound {`
190			`b \|= 0x20`
191			`}`
192			`if t.tag >= 31 {`
193			`b \|= 0x1f`
194			`err = out.WriteByte(b)`
195			`if err != nil {`
196			`return`
197			`}`
198			`err = marshalBase128Int(out, int64(t.tag))`
199			`if err != nil {`
200			`return`
201			`}`
202			`} else {`
203			`b \|= uint8(t.tag)`
204			`err = out.WriteByte(b)`
205			`if err != nil {`
206			`return`
207			`}`
208			`}`
209
210			`if t.length >= 128 {`
211			`l := lengthLength(t.length)`
212			`err = out.WriteByte(0x80 \| byte(l))`
213			`if err != nil {`
214			`return`
215			`}`
216			`err = marshalLength(out, t.length)`
217			`if err != nil {`
218			`return`
219			`}`
220			`} else {`
221			`err = out.WriteByte(byte(t.length))`
222			`if err != nil {`
223			`return`
224			`}`
225			`}`
226
227			`return nil`
228			`}`
229
230			`func marshalBitString(out *forkableWriter, b BitString) (err error) {`
231			`paddingBits := byte((8 - b.BitLength%8) % 8)`
232			`err = out.WriteByte(paddingBits)`
233			`if err != nil {`
234			`return`
235			`}`
236			`_, err = out.Write(b.Bytes)`
237			`return`
238			`}`
239
240			`func marshalObjectIdentifier(out *forkableWriter, oid []int) (err error) {`
241			`if len(oid) < 2 \|\| oid[0] > 6 \|\| oid[1] >= 40 {`
242			`return StructuralError{"invalid object identifier"}`
243			`}`
244
245			`err = out.WriteByte(byte(oid[0]*40 + oid[1]))`
246			`if err != nil {`
247			`return`
248			`}`
249			`for i := 2; i < len(oid); i++ {`
250			`err = marshalBase128Int(out, int64(oid[i]))`
251			`if err != nil {`
252			`return`
253			`}`
254			`}`
255
256			`return`
257			`}`
258
259			`func marshalPrintableString(out *forkableWriter, s string) (err error) {`
260			`b := []byte(s)`
261			`for _, c := range b {`
262			`if !isPrintable(c) {`
263			`return StructuralError{"PrintableString contains invalid character"}`
264			`}`
265			`}`
266
267			`_, err = out.Write(b)`
268			`return`
269			`}`
270
271			`func marshalIA5String(out *forkableWriter, s string) (err error) {`
272			`b := []byte(s)`
273			`for _, c := range b {`
274			`if c > 127 {`
275			`return StructuralError{"IA5String contains invalid character"}`
276			`}`
277			`}`
278
279			`_, err = out.Write(b)`
280			`return`
281			`}`
282
283			`func marshalTwoDigits(out *forkableWriter, v int) (err error) {`
284			`err = out.WriteByte(byte('0' + (v/10)%10))`
285			`if err != nil {`
286			`return`
287			`}`
288			`return out.WriteByte(byte('0' + v%10))`
289			`}`
290
291			`func marshalUTCTime(out *forkableWriter, t time.Time) (err error) {`
292			`utc := t.UTC()`
293			`year, month, day := utc.Date()`
294
295			`switch {`
296			`case 1950 <= year && year < 2000:`
297			`err = marshalTwoDigits(out, int(year-1900))`
298			`case 2000 <= year && year < 2050:`
299			`err = marshalTwoDigits(out, int(year-2000))`
300			`default:`
301			`return StructuralError{"Cannot represent time as UTCTime"}`
302			`}`
303			`if err != nil {`
304			`return`
305			`}`
306
307			`err = marshalTwoDigits(out, int(month))`
308			`if err != nil {`
309			`return`
310			`}`
311
312			`err = marshalTwoDigits(out, day)`
313			`if err != nil {`
314			`return`
315			`}`
316
317			`hour, min, sec := utc.Clock()`
318
319			`err = marshalTwoDigits(out, hour)`
320			`if err != nil {`
321			`return`
322			`}`
323
324			`err = marshalTwoDigits(out, min)`
325			`if err != nil {`
326			`return`
327			`}`
328
329			`err = marshalTwoDigits(out, sec)`
330			`if err != nil {`
331			`return`
332			`}`
333
334			`_, offset := t.Zone()`
335
336			`switch {`
337			`case offset/60 == 0:`
338			`err = out.WriteByte('Z')`
339			`return`
340			`case offset > 0:`
341			`err = out.WriteByte('+')`
342			`case offset < 0:`
343			`err = out.WriteByte('-')`
344			`}`
345
346			`if err != nil {`
347			`return`
348			`}`
349
350			`offsetMinutes := offset / 60`
351			`if offsetMinutes < 0 {`
352			`offsetMinutes = -offsetMinutes`
353			`}`
354
355			`err = marshalTwoDigits(out, offsetMinutes/60)`
356			`if err != nil {`
357			`return`
358			`}`
359
360			`err = marshalTwoDigits(out, offsetMinutes%60)`
361			`return`
362			`}`
363
364			`func stripTagAndLength(in []byte) []byte {`
365			`_, offset, err := parseTagAndLength(in, 0)`
366			`if err != nil {`
367			`return in`
368			`}`
369			`return in[offset:]`
370			`}`
371
372			`func marshalBody(out *forkableWriter, value reflect.Value, params fieldParameters) (err error) {`
373			`switch value.Type() {`
374			`case timeType:`
375			`return marshalUTCTime(out, value.Interface().(time.Time))`
376			`case bitStringType:`
377			`return marshalBitString(out, value.Interface().(BitString))`
378			`case objectIdentifierType:`
379			`return marshalObjectIdentifier(out, value.Interface().(ObjectIdentifier))`
380			`case bigIntType:`
381			`return marshalBigInt(out, value.Interface().(*big.Int))`
382			`}`
383
384			`switch v := value; v.Kind() {`
385			`case reflect.Bool:`
386			`if v.Bool() {`
387			`return out.WriteByte(255)`
388			`} else {`
389			`return out.WriteByte(0)`
390			`}`
391			`case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:`
392			`return marshalInt64(out, int64(v.Int()))`
393			`case reflect.Struct:`
394			`t := v.Type()`
395
396			`startingField := 0`
397
398			`// If the first element of the structure is a non-empty`
399			`// RawContents, then we don't bother serializing the rest.`
400			`if t.NumField() > 0 && t.Field(0).Type == rawContentsType {`
401			`s := v.Field(0)`
402			`if s.Len() > 0 {`
403			`bytes := make([]byte, s.Len())`
404			`for i := 0; i < s.Len(); i++ {`
405			`bytes[i] = uint8(s.Index(i).Uint())`
406			`}`
407			`/* The RawContents will contain the tag and`
408			`* length fields but we'll also be writing`
409			`* those ourselves, so we strip them out of`
410			`* bytes */`
411			`_, err = out.Write(stripTagAndLength(bytes))`
412			`return`
413			`} else {`
414			`startingField = 1`
415			`}`
416			`}`
417
418			`for i := startingField; i < t.NumField(); i++ {`
419			`var pre *forkableWriter`
420			`pre, out = out.fork()`
421			`err = marshalField(pre, v.Field(i), parseFieldParameters(t.Field(i).Tag.Get("asn1")))`
422			`if err != nil {`
423			`return`
424			`}`
425			`}`
426			`return`
427			`case reflect.Slice:`
428			`sliceType := v.Type()`
429			`if sliceType.Elem().Kind() == reflect.Uint8 {`
430			`bytes := make([]byte, v.Len())`
431			`for i := 0; i < v.Len(); i++ {`
432			`bytes[i] = uint8(v.Index(i).Uint())`
433			`}`
434			`_, err = out.Write(bytes)`
435			`return`
436			`}`
437
438			`var params fieldParameters`
439			`for i := 0; i < v.Len(); i++ {`
440			`var pre *forkableWriter`
441			`pre, out = out.fork()`
442			`err = marshalField(pre, v.Index(i), params)`
443			`if err != nil {`
444			`return`
445			`}`
446			`}`
447			`return`
448			`case reflect.String:`
449			`if params.stringType == tagIA5String {`
450			`return marshalIA5String(out, v.String())`
451			`} else {`
452			`return marshalPrintableString(out, v.String())`
453			`}`
454			`return`
455			`}`
456
457			`return StructuralError{"unknown Go type"}`
458			`}`
459
460			`func marshalField(out *forkableWriter, v reflect.Value, params fieldParameters) (err error) {`
461			`// If the field is an interface{} then recurse into it.`
462			`if v.Kind() == reflect.Interface && v.Type().NumMethod() == 0 {`
463			`return marshalField(out, v.Elem(), params)`
464			`}`
465
466			`if params.optional && reflect.DeepEqual(v.Interface(), reflect.Zero(v.Type()).Interface()) {`
467			`return`
468			`}`
469
470			`if v.Type() == rawValueType {`
471			`rv := v.Interface().(RawValue)`
472			`if len(rv.FullBytes) != 0 {`
473			`_, err = out.Write(rv.FullBytes)`
474			`} else {`
475			`err = marshalTagAndLength(out, tagAndLength{rv.Class, rv.Tag, len(rv.Bytes), rv.IsCompound})`
476			`if err != nil {`
477			`return`
478			`}`
479			`_, err = out.Write(rv.Bytes)`
480			`}`
481			`return`
482			`}`
483
484			`tag, isCompound, ok := getUniversalType(v.Type())`
485			`if !ok {`
486			`err = StructuralError{fmt.Sprintf("unknown Go type: %v", v.Type())}`
487			`return`
488			`}`
489			`class := classUniversal`
490
491			`if params.stringType != 0 {`
492			`if tag != tagPrintableString {`
493			`return StructuralError{"Explicit string type given to non-string member"}`
494			`}`
495			`tag = params.stringType`
496			`}`
497
498			`if params.set {`
499			`if tag != tagSequence {`
500			`return StructuralError{"Non sequence tagged as set"}`
501			`}`
502			`tag = tagSet`
503			`}`
504
505			`tags, body := out.fork()`
506
507			`err = marshalBody(body, v, params)`
508			`if err != nil {`
509			`return`
510			`}`
511
512			`bodyLen := body.Len()`
513
514			`var explicitTag *forkableWriter`
515			`if params.explicit {`
516			`explicitTag, tags = tags.fork()`
517			`}`
518
519			`if !params.explicit && params.tag != nil {`
520			`// implicit tag.`
521			`tag = *params.tag`
522			`class = classContextSpecific`
523			`}`
524
525			`err = marshalTagAndLength(tags, tagAndLength{class, tag, bodyLen, isCompound})`
526			`if err != nil {`
527			`return`
528			`}`
529
530			`if params.explicit {`
531			`err = marshalTagAndLength(explicitTag, tagAndLength{`
532			`class: classContextSpecific,`
533			`tag: *params.tag,`
534			`length: bodyLen + tags.Len(),`
535			`isCompound: true,`
536			`})`
537			`}`
538
539			`return nil`
540			`}`
541
542			`// Marshal returns the ASN.1 encoding of val.`
543			`func Marshal(val interface{}) ([]byte, error) {`
544			`var out bytes.Buffer`
545			`v := reflect.ValueOf(val)`
546			`f := newForkableWriter()`
547			`err := marshalField(f, v, fieldParameters{})`
548			`if err != nil {`
549			`return nil, err`
550			`}`
551			`_, err = f.writeTo(&out)`
552			`return out.Bytes(), nil`
553			`}`