1 4b33cdd0 2015-11-30 stephen.d package p9p
3 4b33cdd0 2015-11-30 stephen.d import (
5 4b33cdd0 2015-11-30 stephen.d "encoding/binary"
9 4b33cdd0 2015-11-30 stephen.d "reflect"
10 4b33cdd0 2015-11-30 stephen.d "strings"
14 4b33cdd0 2015-11-30 stephen.d // Codec defines the interface for encoding and decoding of 9p types.
15 4b33cdd0 2015-11-30 stephen.d // Unsupported types will throw an error.
16 4b33cdd0 2015-11-30 stephen.d type Codec interface {
17 4b33cdd0 2015-11-30 stephen.d // Unmarshal from data into the value pointed to by v.
18 4b33cdd0 2015-11-30 stephen.d Unmarshal(data []byte, v interface{}) error
20 4b33cdd0 2015-11-30 stephen.d // Marshal the value v into a byte slice.
21 4b33cdd0 2015-11-30 stephen.d Marshal(v interface{}) ([]byte, error)
23 4b33cdd0 2015-11-30 stephen.d // Size returns the encoded size for the target of v.
24 4b33cdd0 2015-11-30 stephen.d Size(v interface{}) int
27 a0568195 2016-05-23 stevvooe // NewCodec returns a new, standard 9P2000 codec, ready for use.
28 4b33cdd0 2015-11-30 stephen.d func NewCodec() Codec {
29 4b33cdd0 2015-11-30 stephen.d return codec9p{}
32 4b33cdd0 2015-11-30 stephen.d type codec9p struct{}
34 4b33cdd0 2015-11-30 stephen.d func (c codec9p) Unmarshal(data []byte, v interface{}) error {
35 4b33cdd0 2015-11-30 stephen.d dec := &decoder{bytes.NewReader(data)}
36 4b33cdd0 2015-11-30 stephen.d return dec.decode(v)
39 4b33cdd0 2015-11-30 stephen.d func (c codec9p) Marshal(v interface{}) ([]byte, error) {
40 4b33cdd0 2015-11-30 stephen.d var b bytes.Buffer
41 4b33cdd0 2015-11-30 stephen.d enc := &encoder{&b}
43 4b33cdd0 2015-11-30 stephen.d if err := enc.encode(v); err != nil {
44 4b33cdd0 2015-11-30 stephen.d return nil, err
47 4b33cdd0 2015-11-30 stephen.d return b.Bytes(), nil
50 4b33cdd0 2015-11-30 stephen.d func (c codec9p) Size(v interface{}) int {
51 4b33cdd0 2015-11-30 stephen.d return int(size9p(v))
54 4b33cdd0 2015-11-30 stephen.d // DecodeDir decodes a directory entry from rd using the provided codec.
55 4b33cdd0 2015-11-30 stephen.d func DecodeDir(codec Codec, rd io.Reader, d *Dir) error {
56 4b33cdd0 2015-11-30 stephen.d var ll uint16
58 4b33cdd0 2015-11-30 stephen.d // pull the size off the wire
59 4b33cdd0 2015-11-30 stephen.d if err := binary.Read(rd, binary.LittleEndian, &ll); err != nil {
60 4b33cdd0 2015-11-30 stephen.d return err
63 4b33cdd0 2015-11-30 stephen.d p := make([]byte, ll+2)
64 4b33cdd0 2015-11-30 stephen.d binary.LittleEndian.PutUint16(p, ll) // must have size at start
66 4b33cdd0 2015-11-30 stephen.d // read out the rest of the record
67 4b33cdd0 2015-11-30 stephen.d if _, err := io.ReadFull(rd, p[2:]); err != nil {
68 4b33cdd0 2015-11-30 stephen.d return err
71 4b33cdd0 2015-11-30 stephen.d return codec.Unmarshal(p, d)
74 4b33cdd0 2015-11-30 stephen.d // EncodeDir writes the directory to wr.
75 4b33cdd0 2015-11-30 stephen.d func EncodeDir(codec Codec, wr io.Writer, d *Dir) error {
76 4b33cdd0 2015-11-30 stephen.d p, err := codec.Marshal(d)
77 4b33cdd0 2015-11-30 stephen.d if err != nil {
78 4b33cdd0 2015-11-30 stephen.d return err
81 4b33cdd0 2015-11-30 stephen.d _, err = wr.Write(p)
82 4b33cdd0 2015-11-30 stephen.d return err
85 4b33cdd0 2015-11-30 stephen.d type encoder struct {
86 4b33cdd0 2015-11-30 stephen.d wr io.Writer
89 4b33cdd0 2015-11-30 stephen.d func (e *encoder) encode(vs ...interface{}) error {
90 4b33cdd0 2015-11-30 stephen.d for _, v := range vs {
91 4b33cdd0 2015-11-30 stephen.d switch v := v.(type) {
92 4b33cdd0 2015-11-30 stephen.d case uint8, uint16, uint32, uint64, FcallType, Tag, QType, Fid, Flag,
93 4b33cdd0 2015-11-30 stephen.d *uint8, *uint16, *uint32, *uint64, *FcallType, *Tag, *QType, *Fid, *Flag:
94 4b33cdd0 2015-11-30 stephen.d if err := binary.Write(e.wr, binary.LittleEndian, v); err != nil {
95 4b33cdd0 2015-11-30 stephen.d return err
97 4b33cdd0 2015-11-30 stephen.d case []byte:
98 4b33cdd0 2015-11-30 stephen.d if err := e.encode(uint32(len(v))); err != nil {
99 4b33cdd0 2015-11-30 stephen.d return err
102 4b33cdd0 2015-11-30 stephen.d if err := binary.Write(e.wr, binary.LittleEndian, v); err != nil {
103 4b33cdd0 2015-11-30 stephen.d return err
106 4b33cdd0 2015-11-30 stephen.d case *[]byte:
107 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
108 4b33cdd0 2015-11-30 stephen.d return err
110 4b33cdd0 2015-11-30 stephen.d case string:
111 4b33cdd0 2015-11-30 stephen.d if err := binary.Write(e.wr, binary.LittleEndian, uint16(len(v))); err != nil {
112 4b33cdd0 2015-11-30 stephen.d return err
115 4b33cdd0 2015-11-30 stephen.d _, err := io.WriteString(e.wr, v)
116 4b33cdd0 2015-11-30 stephen.d if err != nil {
117 4b33cdd0 2015-11-30 stephen.d return err
119 4b33cdd0 2015-11-30 stephen.d case *string:
120 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
121 4b33cdd0 2015-11-30 stephen.d return err
124 4b33cdd0 2015-11-30 stephen.d case []string:
125 4b33cdd0 2015-11-30 stephen.d if err := e.encode(uint16(len(v))); err != nil {
126 4b33cdd0 2015-11-30 stephen.d return err
129 4b33cdd0 2015-11-30 stephen.d for _, m := range v {
130 4b33cdd0 2015-11-30 stephen.d if err := e.encode(m); err != nil {
131 4b33cdd0 2015-11-30 stephen.d return err
134 4b33cdd0 2015-11-30 stephen.d case *[]string:
135 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
136 4b33cdd0 2015-11-30 stephen.d return err
138 4b33cdd0 2015-11-30 stephen.d case time.Time:
139 4b33cdd0 2015-11-30 stephen.d if err := e.encode(uint32(v.Unix())); err != nil {
140 4b33cdd0 2015-11-30 stephen.d return err
142 4b33cdd0 2015-11-30 stephen.d case *time.Time:
143 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
144 4b33cdd0 2015-11-30 stephen.d return err
146 4b33cdd0 2015-11-30 stephen.d case Qid:
147 4b33cdd0 2015-11-30 stephen.d if err := e.encode(v.Type, v.Version, v.Path); err != nil {
148 4b33cdd0 2015-11-30 stephen.d return err
150 4b33cdd0 2015-11-30 stephen.d case *Qid:
151 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
152 4b33cdd0 2015-11-30 stephen.d return err
154 4b33cdd0 2015-11-30 stephen.d case []Qid:
155 4b33cdd0 2015-11-30 stephen.d if err := e.encode(uint16(len(v))); err != nil {
156 4b33cdd0 2015-11-30 stephen.d return err
159 4b33cdd0 2015-11-30 stephen.d elements := make([]interface{}, len(v))
160 4b33cdd0 2015-11-30 stephen.d for i := range v {
161 4b33cdd0 2015-11-30 stephen.d elements[i] = &v[i]
164 4b33cdd0 2015-11-30 stephen.d if err := e.encode(elements...); err != nil {
165 4b33cdd0 2015-11-30 stephen.d return err
167 4b33cdd0 2015-11-30 stephen.d case *[]Qid:
168 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
169 4b33cdd0 2015-11-30 stephen.d return err
171 4b33cdd0 2015-11-30 stephen.d case Dir:
172 4b33cdd0 2015-11-30 stephen.d elements, err := fields9p(v)
173 4b33cdd0 2015-11-30 stephen.d if err != nil {
174 4b33cdd0 2015-11-30 stephen.d return err
177 4b33cdd0 2015-11-30 stephen.d if err := e.encode(uint16(size9p(elements...))); err != nil {
178 4b33cdd0 2015-11-30 stephen.d return err
181 4b33cdd0 2015-11-30 stephen.d if err := e.encode(elements...); err != nil {
182 4b33cdd0 2015-11-30 stephen.d return err
184 4b33cdd0 2015-11-30 stephen.d case *Dir:
185 961194b3 2015-12-04 stevvooe if err := e.encode(*v); err != nil {
186 961194b3 2015-12-04 stevvooe return err
188 961194b3 2015-12-04 stevvooe case []Dir:
189 961194b3 2015-12-04 stevvooe elements := make([]interface{}, len(v))
190 961194b3 2015-12-04 stevvooe for i := range v {
191 961194b3 2015-12-04 stevvooe elements[i] = &v[i]
194 961194b3 2015-12-04 stevvooe if err := e.encode(elements...); err != nil {
195 961194b3 2015-12-04 stevvooe return err
197 961194b3 2015-12-04 stevvooe case *[]Dir:
198 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
199 4b33cdd0 2015-11-30 stephen.d return err
201 4b33cdd0 2015-11-30 stephen.d case Fcall:
202 4b33cdd0 2015-11-30 stephen.d if err := e.encode(v.Type, v.Tag, v.Message); err != nil {
203 4b33cdd0 2015-11-30 stephen.d return err
205 4b33cdd0 2015-11-30 stephen.d case *Fcall:
206 4b33cdd0 2015-11-30 stephen.d if err := e.encode(*v); err != nil {
207 4b33cdd0 2015-11-30 stephen.d return err
209 4b33cdd0 2015-11-30 stephen.d case Message:
210 4b33cdd0 2015-11-30 stephen.d elements, err := fields9p(v)
211 4b33cdd0 2015-11-30 stephen.d if err != nil {
212 4b33cdd0 2015-11-30 stephen.d return err
215 4b33cdd0 2015-11-30 stephen.d switch v.(type) {
216 4b33cdd0 2015-11-30 stephen.d case MessageRstat, *MessageRstat:
217 4b33cdd0 2015-11-30 stephen.d // NOTE(stevvooe): Prepend size preceeding Dir. See bugs in
218 4b33cdd0 2015-11-30 stephen.d // http://man.cat-v.org/plan_9/5/stat to make sense of this.
219 4b33cdd0 2015-11-30 stephen.d // The field has been included here but we need to make sure
220 4b33cdd0 2015-11-30 stephen.d // to double emit it for Rstat.
221 4b33cdd0 2015-11-30 stephen.d if err := e.encode(uint16(size9p(elements...))); err != nil {
222 4b33cdd0 2015-11-30 stephen.d return err
226 4b33cdd0 2015-11-30 stephen.d if err := e.encode(elements...); err != nil {
227 4b33cdd0 2015-11-30 stephen.d return err
232 4b33cdd0 2015-11-30 stephen.d return nil
235 4b33cdd0 2015-11-30 stephen.d type decoder struct {
236 4b33cdd0 2015-11-30 stephen.d rd io.Reader
239 4b33cdd0 2015-11-30 stephen.d // read9p extracts values from rd and unmarshals them to the targets of vs.
240 4b33cdd0 2015-11-30 stephen.d func (d *decoder) decode(vs ...interface{}) error {
241 4b33cdd0 2015-11-30 stephen.d for _, v := range vs {
242 4b33cdd0 2015-11-30 stephen.d switch v := v.(type) {
243 4b33cdd0 2015-11-30 stephen.d case *uint8, *uint16, *uint32, *uint64, *FcallType, *Tag, *QType, *Fid, *Flag:
244 4b33cdd0 2015-11-30 stephen.d if err := binary.Read(d.rd, binary.LittleEndian, v); err != nil {
245 4b33cdd0 2015-11-30 stephen.d return err
247 4b33cdd0 2015-11-30 stephen.d case *[]byte:
248 4b33cdd0 2015-11-30 stephen.d var ll uint32
250 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&ll); err != nil {
251 4b33cdd0 2015-11-30 stephen.d return err
254 4b33cdd0 2015-11-30 stephen.d *v = make([]byte, int(ll))
256 4b33cdd0 2015-11-30 stephen.d if err := binary.Read(d.rd, binary.LittleEndian, v); err != nil {
257 4b33cdd0 2015-11-30 stephen.d return err
259 4b33cdd0 2015-11-30 stephen.d case *string:
260 4b33cdd0 2015-11-30 stephen.d var ll uint16
262 4b33cdd0 2015-11-30 stephen.d // implement string[s] encoding
263 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&ll); err != nil {
264 4b33cdd0 2015-11-30 stephen.d return err
267 4b33cdd0 2015-11-30 stephen.d b := make([]byte, ll)
269 4b33cdd0 2015-11-30 stephen.d n, err := io.ReadFull(d.rd, b)
270 4b33cdd0 2015-11-30 stephen.d if err != nil {
271 4b33cdd0 2015-11-30 stephen.d return err
274 4b33cdd0 2015-11-30 stephen.d if n != int(ll) {
275 4b33cdd0 2015-11-30 stephen.d return fmt.Errorf("unexpected string length")
278 4b33cdd0 2015-11-30 stephen.d *v = string(b)
279 4b33cdd0 2015-11-30 stephen.d case *[]string:
280 4b33cdd0 2015-11-30 stephen.d var ll uint16
282 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&ll); err != nil {
283 4b33cdd0 2015-11-30 stephen.d return err
286 4b33cdd0 2015-11-30 stephen.d elements := make([]interface{}, int(ll))
287 4b33cdd0 2015-11-30 stephen.d *v = make([]string, int(ll))
288 4b33cdd0 2015-11-30 stephen.d for i := range elements {
289 4b33cdd0 2015-11-30 stephen.d elements[i] = &(*v)[i]
292 4b33cdd0 2015-11-30 stephen.d if err := d.decode(elements...); err != nil {
293 4b33cdd0 2015-11-30 stephen.d return err
295 4b33cdd0 2015-11-30 stephen.d case *time.Time:
296 4b33cdd0 2015-11-30 stephen.d var epoch uint32
297 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&epoch); err != nil {
298 4b33cdd0 2015-11-30 stephen.d return err
301 4b33cdd0 2015-11-30 stephen.d *v = time.Unix(int64(epoch), 0).UTC()
302 4b33cdd0 2015-11-30 stephen.d case *Qid:
303 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&v.Type, &v.Version, &v.Path); err != nil {
304 4b33cdd0 2015-11-30 stephen.d return err
306 4b33cdd0 2015-11-30 stephen.d case *[]Qid:
307 4b33cdd0 2015-11-30 stephen.d var ll uint16
309 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&ll); err != nil {
310 4b33cdd0 2015-11-30 stephen.d return err
313 4b33cdd0 2015-11-30 stephen.d elements := make([]interface{}, int(ll))
314 4b33cdd0 2015-11-30 stephen.d *v = make([]Qid, int(ll))
315 4b33cdd0 2015-11-30 stephen.d for i := range elements {
316 4b33cdd0 2015-11-30 stephen.d elements[i] = &(*v)[i]
319 4b33cdd0 2015-11-30 stephen.d if err := d.decode(elements...); err != nil {
320 4b33cdd0 2015-11-30 stephen.d return err
322 4b33cdd0 2015-11-30 stephen.d case *Dir:
323 4b33cdd0 2015-11-30 stephen.d var ll uint16
325 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&ll); err != nil {
326 4b33cdd0 2015-11-30 stephen.d return err
329 4b33cdd0 2015-11-30 stephen.d b := make([]byte, ll)
330 4b33cdd0 2015-11-30 stephen.d // must consume entire dir entry.
331 4b33cdd0 2015-11-30 stephen.d n, err := io.ReadFull(d.rd, b)
332 4b33cdd0 2015-11-30 stephen.d if err != nil {
333 4b33cdd0 2015-11-30 stephen.d log.Println("dir readfull failed:", err, ll, n)
334 4b33cdd0 2015-11-30 stephen.d return err
337 4b33cdd0 2015-11-30 stephen.d elements, err := fields9p(v)
338 4b33cdd0 2015-11-30 stephen.d if err != nil {
339 4b33cdd0 2015-11-30 stephen.d return err
342 4b33cdd0 2015-11-30 stephen.d dec := &decoder{bytes.NewReader(b)}
344 4b33cdd0 2015-11-30 stephen.d if err := dec.decode(elements...); err != nil {
345 4b33cdd0 2015-11-30 stephen.d return err
347 961194b3 2015-12-04 stevvooe case *[]Dir:
348 961194b3 2015-12-04 stevvooe *v = make([]Dir, 0)
350 961194b3 2015-12-04 stevvooe element := Dir{}
351 961194b3 2015-12-04 stevvooe if err := d.decode(&element); err != nil {
352 961194b3 2015-12-04 stevvooe if err == io.EOF {
353 961194b3 2015-12-04 stevvooe return nil
355 961194b3 2015-12-04 stevvooe return err
357 961194b3 2015-12-04 stevvooe *v = append(*v, element)
359 4b33cdd0 2015-11-30 stephen.d case *Fcall:
360 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&v.Type, &v.Tag); err != nil {
361 4b33cdd0 2015-11-30 stephen.d return err
364 4b33cdd0 2015-11-30 stephen.d message, err := newMessage(v.Type)
365 4b33cdd0 2015-11-30 stephen.d if err != nil {
366 4b33cdd0 2015-11-30 stephen.d return err
369 4b33cdd0 2015-11-30 stephen.d // NOTE(stevvooe): We do a little pointer dance to allocate the
370 4b33cdd0 2015-11-30 stephen.d // new type, write to it, then assign it back to the interface as
371 4b33cdd0 2015-11-30 stephen.d // a concrete type, avoiding a pointer (the interface) to a
372 4b33cdd0 2015-11-30 stephen.d // pointer.
373 4b33cdd0 2015-11-30 stephen.d rv := reflect.New(reflect.TypeOf(message))
374 4b33cdd0 2015-11-30 stephen.d if err := d.decode(rv.Interface()); err != nil {
375 4b33cdd0 2015-11-30 stephen.d return err
378 4b33cdd0 2015-11-30 stephen.d v.Message = rv.Elem().Interface().(Message)
379 4b33cdd0 2015-11-30 stephen.d case Message:
380 4b33cdd0 2015-11-30 stephen.d elements, err := fields9p(v)
381 4b33cdd0 2015-11-30 stephen.d if err != nil {
382 4b33cdd0 2015-11-30 stephen.d return err
385 4b33cdd0 2015-11-30 stephen.d switch v.(type) {
386 4b33cdd0 2015-11-30 stephen.d case *MessageRstat, MessageRstat:
387 4b33cdd0 2015-11-30 stephen.d // NOTE(stevvooe): Consume extra size preceeding Dir. See bugs
388 4b33cdd0 2015-11-30 stephen.d // in http://man.cat-v.org/plan_9/5/stat to make sense of
389 4b33cdd0 2015-11-30 stephen.d // this. The field has been included here but we need to make
390 4b33cdd0 2015-11-30 stephen.d // sure to double emit it for Rstat. decode extra size header
391 4b33cdd0 2015-11-30 stephen.d // for stat structure.
392 4b33cdd0 2015-11-30 stephen.d var ll uint16
393 4b33cdd0 2015-11-30 stephen.d if err := d.decode(&ll); err != nil {
394 4b33cdd0 2015-11-30 stephen.d return err
398 4b33cdd0 2015-11-30 stephen.d if err := d.decode(elements...); err != nil {
399 4b33cdd0 2015-11-30 stephen.d return err
404 4b33cdd0 2015-11-30 stephen.d return nil
407 4b33cdd0 2015-11-30 stephen.d // size9p calculates the projected size of the values in vs when encoded into
408 4b33cdd0 2015-11-30 stephen.d // 9p binary protocol. If an element or elements are not valid for 9p encoded,
409 4b33cdd0 2015-11-30 stephen.d // the value 0 will be used for the size. The error will be detected when
410 4b33cdd0 2015-11-30 stephen.d // encoding.
411 4b33cdd0 2015-11-30 stephen.d func size9p(vs ...interface{}) uint32 {
412 4b33cdd0 2015-11-30 stephen.d var s uint32
413 4b33cdd0 2015-11-30 stephen.d for _, v := range vs {
414 4b33cdd0 2015-11-30 stephen.d if v == nil {
415 4b33cdd0 2015-11-30 stephen.d continue
418 4b33cdd0 2015-11-30 stephen.d switch v := v.(type) {
419 4b33cdd0 2015-11-30 stephen.d case uint8, uint16, uint32, uint64, FcallType, Tag, QType, Fid, Flag,
420 4b33cdd0 2015-11-30 stephen.d *uint8, *uint16, *uint32, *uint64, *FcallType, *Tag, *QType, *Fid, *Flag:
421 4b33cdd0 2015-11-30 stephen.d s += uint32(binary.Size(v))
422 4b33cdd0 2015-11-30 stephen.d case []byte:
423 4b33cdd0 2015-11-30 stephen.d s += uint32(binary.Size(uint32(0)) + len(v))
424 4b33cdd0 2015-11-30 stephen.d case *[]byte:
425 4b33cdd0 2015-11-30 stephen.d s += size9p(uint32(0), *v)
426 4b33cdd0 2015-11-30 stephen.d case string:
427 4b33cdd0 2015-11-30 stephen.d s += uint32(binary.Size(uint16(0)) + len(v))
428 4b33cdd0 2015-11-30 stephen.d case *string:
429 4b33cdd0 2015-11-30 stephen.d s += size9p(*v)
430 4b33cdd0 2015-11-30 stephen.d case []string:
431 4b33cdd0 2015-11-30 stephen.d s += size9p(uint16(0))
433 4b33cdd0 2015-11-30 stephen.d for _, sv := range v {
434 4b33cdd0 2015-11-30 stephen.d s += size9p(sv)
436 4b33cdd0 2015-11-30 stephen.d case *[]string:
437 4b33cdd0 2015-11-30 stephen.d s += size9p(*v)
438 4b33cdd0 2015-11-30 stephen.d case time.Time, *time.Time:
439 4b33cdd0 2015-11-30 stephen.d // BUG(stevvooe): Y2038 is coming.
440 4b33cdd0 2015-11-30 stephen.d s += size9p(uint32(0))
441 4b33cdd0 2015-11-30 stephen.d case Qid:
442 4b33cdd0 2015-11-30 stephen.d s += size9p(v.Type, v.Version, v.Path)
443 4b33cdd0 2015-11-30 stephen.d case *Qid:
444 4b33cdd0 2015-11-30 stephen.d s += size9p(*v)
445 4b33cdd0 2015-11-30 stephen.d case []Qid:
446 4b33cdd0 2015-11-30 stephen.d s += size9p(uint16(0))
447 4b33cdd0 2015-11-30 stephen.d elements := make([]interface{}, len(v))
448 4b33cdd0 2015-11-30 stephen.d for i := range elements {
449 4b33cdd0 2015-11-30 stephen.d elements[i] = &v[i]
451 4b33cdd0 2015-11-30 stephen.d s += size9p(elements...)
452 4b33cdd0 2015-11-30 stephen.d case *[]Qid:
453 4b33cdd0 2015-11-30 stephen.d s += size9p(*v)
455 4b33cdd0 2015-11-30 stephen.d case Dir:
456 4b33cdd0 2015-11-30 stephen.d // walk the fields of the message to get the total size. we just
457 4b33cdd0 2015-11-30 stephen.d // use the field order from the message struct. We may add tag
458 4b33cdd0 2015-11-30 stephen.d // ignoring if needed.
459 4b33cdd0 2015-11-30 stephen.d elements, err := fields9p(v)
460 4b33cdd0 2015-11-30 stephen.d if err != nil {
461 4b33cdd0 2015-11-30 stephen.d // BUG(stevvooe): The options here are to return 0, panic or
462 4b33cdd0 2015-11-30 stephen.d // make this return an error. Ideally, we make it safe to
463 4b33cdd0 2015-11-30 stephen.d // return 0 and have the rest of the package do the right
464 4b33cdd0 2015-11-30 stephen.d // thing. For now, we do this, but may want to panic until
465 4b33cdd0 2015-11-30 stephen.d // things are stable.
466 4b33cdd0 2015-11-30 stephen.d panic(err)
469 4b33cdd0 2015-11-30 stephen.d s += size9p(elements...) + size9p(uint16(0))
470 4b33cdd0 2015-11-30 stephen.d case *Dir:
471 4b33cdd0 2015-11-30 stephen.d s += size9p(*v)
472 961194b3 2015-12-04 stevvooe case []Dir:
473 961194b3 2015-12-04 stevvooe elements := make([]interface{}, len(v))
474 961194b3 2015-12-04 stevvooe for i := range elements {
475 961194b3 2015-12-04 stevvooe elements[i] = &v[i]
477 961194b3 2015-12-04 stevvooe s += size9p(elements...)
478 961194b3 2015-12-04 stevvooe case *[]Dir:
479 961194b3 2015-12-04 stevvooe s += size9p(*v)
480 4b33cdd0 2015-11-30 stephen.d case Fcall:
481 4b33cdd0 2015-11-30 stephen.d s += size9p(v.Type, v.Tag, v.Message)
482 4b33cdd0 2015-11-30 stephen.d case *Fcall:
483 4b33cdd0 2015-11-30 stephen.d s += size9p(*v)
484 4b33cdd0 2015-11-30 stephen.d case Message:
485 4b33cdd0 2015-11-30 stephen.d // special case twstat and rstat for size fields. See bugs in
486 4b33cdd0 2015-11-30 stephen.d // http://man.cat-v.org/plan_9/5/stat to make sense of this.
487 4b33cdd0 2015-11-30 stephen.d switch v.(type) {
488 4b33cdd0 2015-11-30 stephen.d case *MessageRstat, MessageRstat:
489 4b33cdd0 2015-11-30 stephen.d s += size9p(uint16(0)) // for extra size field before dir
492 4b33cdd0 2015-11-30 stephen.d // walk the fields of the message to get the total size. we just
493 4b33cdd0 2015-11-30 stephen.d // use the field order from the message struct. We may add tag
494 4b33cdd0 2015-11-30 stephen.d // ignoring if needed.
495 4b33cdd0 2015-11-30 stephen.d elements, err := fields9p(v)
496 4b33cdd0 2015-11-30 stephen.d if err != nil {
497 4b33cdd0 2015-11-30 stephen.d // BUG(stevvooe): The options here are to return 0, panic or
498 4b33cdd0 2015-11-30 stephen.d // make this return an error. Ideally, we make it safe to
499 4b33cdd0 2015-11-30 stephen.d // return 0 and have the rest of the package do the right
500 4b33cdd0 2015-11-30 stephen.d // thing. For now, we do this, but may want to panic until
501 4b33cdd0 2015-11-30 stephen.d // things are stable.
502 4b33cdd0 2015-11-30 stephen.d panic(err)
505 4b33cdd0 2015-11-30 stephen.d s += size9p(elements...)
509 4b33cdd0 2015-11-30 stephen.d return s
512 4b33cdd0 2015-11-30 stephen.d // fields9p lists the settable fields from a struct type for reading and
513 4b33cdd0 2015-11-30 stephen.d // writing. We are using a lot of reflection here for fairly static
514 4b33cdd0 2015-11-30 stephen.d // serialization but we can replace this in the future with generated code if
515 4b33cdd0 2015-11-30 stephen.d // performance is an issue.
516 4b33cdd0 2015-11-30 stephen.d func fields9p(v interface{}) ([]interface{}, error) {
517 4b33cdd0 2015-11-30 stephen.d rv := reflect.Indirect(reflect.ValueOf(v))
519 4b33cdd0 2015-11-30 stephen.d if rv.Kind() != reflect.Struct {
520 4b33cdd0 2015-11-30 stephen.d return nil, fmt.Errorf("cannot extract fields from non-struct: %v", rv)
523 4b33cdd0 2015-11-30 stephen.d var elements []interface{}
524 4b33cdd0 2015-11-30 stephen.d for i := 0; i < rv.NumField(); i++ {
525 4b33cdd0 2015-11-30 stephen.d f := rv.Field(i)
527 4b33cdd0 2015-11-30 stephen.d if !f.CanInterface() {
528 4b33cdd0 2015-11-30 stephen.d // unexported field, skip it.
529 4b33cdd0 2015-11-30 stephen.d continue
532 4b33cdd0 2015-11-30 stephen.d if f.CanAddr() {
533 4b33cdd0 2015-11-30 stephen.d f = f.Addr()
536 4b33cdd0 2015-11-30 stephen.d elements = append(elements, f.Interface())
539 4b33cdd0 2015-11-30 stephen.d return elements, nil
542 4b33cdd0 2015-11-30 stephen.d func string9p(v interface{}) string {
543 4b33cdd0 2015-11-30 stephen.d if v == nil {
544 4b33cdd0 2015-11-30 stephen.d return "nil"
547 4b33cdd0 2015-11-30 stephen.d rv := reflect.Indirect(reflect.ValueOf(v))
549 4b33cdd0 2015-11-30 stephen.d if rv.Kind() != reflect.Struct {
550 4b33cdd0 2015-11-30 stephen.d panic("not a struct")
553 4b33cdd0 2015-11-30 stephen.d var s string
555 4b33cdd0 2015-11-30 stephen.d for i := 0; i < rv.NumField(); i++ {
556 4b33cdd0 2015-11-30 stephen.d f := rv.Field(i)
558 4b33cdd0 2015-11-30 stephen.d s += fmt.Sprintf(" %v=%v", strings.ToLower(rv.Type().Field(i).Name), f.Interface())
561 4b33cdd0 2015-11-30 stephen.d return s
