aboutsummaryrefslogtreecommitdiffstats
path: root/vendor/github.com/golang/protobuf/proto/pointer_reflect.go
blob: 94fa9194a88231988051f270dfdffe0c7a29572c (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
// Go support for Protocol Buffers - Google's data interchange format
//
// Copyright 2012 The Go Authors.  All rights reserved.
// https://github.com/golang/protobuf
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// +build purego appengine js

// This file contains an implementation of proto field accesses using package reflect.
// It is slower than the code in pointer_unsafe.go but it avoids package unsafe and can
// be used on App Engine.

package proto

import (
    "reflect"
    "sync"
)

const unsafeAllowed = false

// A field identifies a field in a struct, accessible from a pointer.
// In this implementation, a field is identified by the sequence of field indices
// passed to reflect's FieldByIndex.
type field []int

// toField returns a field equivalent to the given reflect field.
func toField(f *reflect.StructField) field {
    return f.Index
}

// invalidField is an invalid field identifier.
var invalidField = field(nil)

// zeroField is a noop when calling pointer.offset.
var zeroField = field([]int{})

// IsValid reports whether the field identifier is valid.
func (f field) IsValid() bool { return f != nil }

// The pointer type is for the table-driven decoder.
// The implementation here uses a reflect.Value of pointer type to
// create a generic pointer. In pointer_unsafe.go we use unsafe
// instead of reflect to implement the same (but faster) interface.
type pointer struct {
    v reflect.Value
}

// toPointer converts an interface of pointer type to a pointer
// that points to the same target.
func toPointer(i *Message) pointer {
    return pointer{v: reflect.ValueOf(*i)}
}

// toAddrPointer converts an interface to a pointer that points to
// the interface data.
func toAddrPointer(i *interface{}, isptr, deref bool) pointer {
    v := reflect.ValueOf(*i)
    u := reflect.New(v.Type())
    u.Elem().Set(v)
    if deref {
        u = u.Elem()
    }
    return pointer{v: u}
}

// valToPointer converts v to a pointer.  v must be of pointer type.
func valToPointer(v reflect.Value) pointer {
    return pointer{v: v}
}

// offset converts from a pointer to a structure to a pointer to
// one of its fields.
func (p pointer) offset(f field) pointer {
    return pointer{v: p.v.Elem().FieldByIndex(f).Addr()}
}

func (p pointer) isNil() bool {
    return p.v.IsNil()
}

// grow updates the slice s in place to make it one element longer.
// s must be addressable.
// Returns the (addressable) new element.
func grow(s reflect.Value) reflect.Value {
    n, m := s.Len(), s.Cap()
    if n < m {
        s.SetLen(n + 1)
    } else {
        s.Set(reflect.Append(s, reflect.Zero(s.Type().Elem())))
    }
    return s.Index(n)
}

func (p pointer) toInt64() *int64 {
    return p.v.Interface().(*int64)
}
func (p pointer) toInt64Ptr() **int64 {
    return p.v.Interface().(**int64)
}
func (p pointer) toInt64Slice() *[]int64 {
    return p.v.Interface().(*[]int64)
}

var int32ptr = reflect.TypeOf((*int32)(nil))

func (p pointer) toInt32() *int32 {
    return p.v.Convert(int32ptr).Interface().(*int32)
}

// The toInt32Ptr/Slice methods don't work because of enums.
// Instead, we must use set/get methods for the int32ptr/slice case.
/*
    func (p pointer) toInt32Ptr() **int32 {
        return p.v.Interface().(**int32)
}
    func (p pointer) toInt32Slice() *[]int32 {
        return p.v.Interface().(*[]int32)
}
*/
func (p pointer) getInt32Ptr() *int32 {
    if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
        // raw int32 type
        return p.v.Elem().Interface().(*int32)
    }
    // an enum
    return p.v.Elem().Convert(int32PtrType).Interface().(*int32)
}
func (p pointer) setInt32Ptr(v int32) {
    // Allocate value in a *int32. Possibly convert that to a *enum.
    // Then assign it to a **int32 or **enum.
    // Note: we can convert *int32 to *enum, but we can't convert
    // **int32 to **enum!
    p.v.Elem().Set(reflect.ValueOf(&v).Convert(p.v.Type().Elem()))
}

// getInt32Slice copies []int32 from p as a new slice.
// This behavior differs from the implementation in pointer_unsafe.go.
func (p pointer) getInt32Slice() []int32 {
    if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
        // raw int32 type
        return p.v.Elem().Interface().([]int32)
    }
    // an enum
    // Allocate a []int32, then assign []enum's values into it.
    // Note: we can't convert []enum to []int32.
    slice := p.v.Elem()
    s := make([]int32, slice.Len())
    for i := 0; i < slice.Len(); i++ {
        s[i] = int32(slice.Index(i).Int())
    }
    return s
}

// setInt32Slice copies []int32 into p as a new slice.
// This behavior differs from the implementation in pointer_unsafe.go.
func (p pointer) setInt32Slice(v []int32) {
    if p.v.Type().Elem().Elem() == reflect.TypeOf(int32(0)) {
        // raw int32 type
        p.v.Elem().Set(reflect.ValueOf(v))
        return
    }
    // an enum
    // Allocate a []enum, then assign []int32's values into it.
    // Note: we can't convert []enum to []int32.
    slice := reflect.MakeSlice(p.v.Type().Elem(), len(v), cap(v))
    for i, x := range v {
        slice.Index(i).SetInt(int64(x))
    }
    p.v.Elem().Set(slice)
}
func (p pointer) appendInt32Slice(v int32) {
    grow(p.v.Elem()).SetInt(int64(v))
}

func (p pointer) toUint64() *uint64 {
    return p.v.Interface().(*uint64)
}
func (p pointer) toUint64Ptr() **uint64 {
    return p.v.Interface().(**uint64)
}
func (p pointer) toUint64Slice() *[]uint64 {
    return p.v.Interface().(*[]uint64)
}
func (p pointer) toUint32() *uint32 {
    return p.v.Interface().(*uint32)
}
func (p pointer) toUint32Ptr() **uint32 {
    return p.v.Interface().(**uint32)
}
func (p pointer) toUint32Slice() *[]uint32 {
    return p.v.Interface().(*[]uint32)
}
func (p pointer) toBool() *bool {
    return p.v.Interface().(*bool)
}
func (p pointer) toBoolPtr() **bool {
    return p.v.Interface().(**bool)
}
func (p pointer) toBoolSlice() *[]bool {
    return p.v.Interface().(*[]bool)
}
func (p pointer) toFloat64() *float64 {
    return p.v.Interface().(*float64)
}
func (p pointer) toFloat64Ptr() **float64 {
    return p.v.Interface().(**float64)
}
func (p pointer) toFloat64Slice() *[]float64 {
    return p.v.Interface().(*[]float64)
}
func (p pointer) toFloat32() *float32 {
    return p.v.Interface().(*float32)
}
func (p pointer) toFloat32Ptr() **float32 {
    return p.v.Interface().(**float32)
}
func (p pointer) toFloat32Slice() *[]float32 {
    return p.v.Interface().(*[]float32)
}
func (p pointer) toString() *string {
    return p.v.Interface().(*string)
}
func (p pointer) toStringPtr() **string {
    return p.v.Interface().(**string)
}
func (p pointer) toStringSlice() *[]string {
    return p.v.Interface().(*[]string)
}
func (p pointer) toBytes() *[]byte {
    return p.v.Interface().(*[]byte)
}
func (p pointer) toBytesSlice() *[][]byte {
    return p.v.Interface().(*[][]byte)
}
func (p pointer) toExtensions() *XXX_InternalExtensions {
    return p.v.Interface().(*XXX_InternalExtensions)
}
func (p pointer) toOldExtensions() *map[int32]Extension {
    return p.v.Interface().(*map[int32]Extension)
}
func (p pointer) getPointer() pointer {
    return pointer{v: p.v.Elem()}
}
func (p pointer) setPointer(q pointer) {
    p.v.Elem().Set(q.v)
}
func (p pointer) appendPointer(q pointer) {
    grow(p.v.Elem()).Set(q.v)
}

// getPointerSlice copies []*T from p as a new []pointer.
// This behavior differs from the implementation in pointer_unsafe.go.
func (p pointer) getPointerSlice() []pointer {
    if p.v.IsNil() {
        return nil
    }
    n := p.v.Elem().Len()
    s := make([]pointer, n)
    for i := 0; i < n; i++ {
        s[i] = pointer{v: p.v.Elem().Index(i)}
    }
    return s
}

// setPointerSlice copies []pointer into p as a new []*T.
// This behavior differs from the implementation in pointer_unsafe.go.
func (p pointer) setPointerSlice(v []pointer) {
    if v == nil {
        p.v.Elem().Set(reflect.New(p.v.Elem().Type()).Elem())
        return
    }
    s := reflect.MakeSlice(p.v.Elem().Type(), 0, len(v))
    for _, p := range v {
        s = reflect.Append(s, p.v)
    }
    p.v.Elem().Set(s)
}

// getInterfacePointer returns a pointer that points to the
// interface data of the interface pointed by p.
func (p pointer) getInterfacePointer() pointer {
    if p.v.Elem().IsNil() {
        return pointer{v: p.v.Elem()}
    }
    return pointer{v: p.v.Elem().Elem().Elem().Field(0).Addr()} // *interface -> interface -> *struct -> struct
}

func (p pointer) asPointerTo(t reflect.Type) reflect.Value {
    // TODO: check that p.v.Type().Elem() == t?
    return p.v
}

func atomicLoadUnmarshalInfo(p **unmarshalInfo) *unmarshalInfo {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    return *p
}
func atomicStoreUnmarshalInfo(p **unmarshalInfo, v *unmarshalInfo) {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    *p = v
}
func atomicLoadMarshalInfo(p **marshalInfo) *marshalInfo {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    return *p
}
func atomicStoreMarshalInfo(p **marshalInfo, v *marshalInfo) {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    *p = v
}
func atomicLoadMergeInfo(p **mergeInfo) *mergeInfo {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    return *p
}
func atomicStoreMergeInfo(p **mergeInfo, v *mergeInfo) {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    *p = v
}
func atomicLoadDiscardInfo(p **discardInfo) *discardInfo {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    return *p
}
func atomicStoreDiscardInfo(p **discardInfo, v *discardInfo) {
    atomicLock.Lock()
    defer atomicLock.Unlock()
    *p = v
}

var atomicLock sync.Mutex