1 // Go support for Protocol Buffers - Google's data interchange format
3 // Copyright 2012 The Go Authors. All rights reserved.
4 // https://github.com/golang/protobuf
6 // Redistribution and use in source and binary forms, with or without
7 // modification, are permitted provided that the following conditions are
10 // * Redistributions of source code must retain the above copyright
11 // notice, this list of conditions and the following disclaimer.
12 // * Redistributions in binary form must reproduce the above
13 // copyright notice, this list of conditions and the following disclaimer
14 // in the documentation and/or other materials provided with the
16 // * Neither the name of Google Inc. nor the names of its
17 // contributors may be used to endorse or promote products derived from
18 // this software without specific prior written permission.
20 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
30 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 // +build !appengine,!js
34 // This file contains the implementation of the proto field accesses using package unsafe.
43 // NOTE: These type_Foo functions would more idiomatically be methods,
44 // but Go does not allow methods on pointer types, and we must preserve
45 // some pointer type for the garbage collector. We use these
46 // funcs with clunky names as our poor approximation to methods.
48 // An alternative would be
49 // type structPointer struct { p unsafe.Pointer }
50 // but that does not registerize as well.
52 // A structPointer is a pointer to a struct.
53 type structPointer unsafe.Pointer
55 // toStructPointer returns a structPointer equivalent to the given reflect value.
56 func toStructPointer(v reflect.Value) structPointer {
57 return structPointer(unsafe.Pointer(v.Pointer()))
60 // IsNil reports whether p is nil.
61 func structPointer_IsNil(p structPointer) bool {
65 // Interface returns the struct pointer, assumed to have element type t,
66 // as an interface value.
67 func structPointer_Interface(p structPointer, t reflect.Type) interface{} {
68 return reflect.NewAt(t, unsafe.Pointer(p)).Interface()
71 // A field identifies a field in a struct, accessible from a structPointer.
72 // In this implementation, a field is identified by its byte offset from the start of the struct.
75 // toField returns a field equivalent to the given reflect field.
76 func toField(f *reflect.StructField) field {
77 return field(f.Offset)
80 // invalidField is an invalid field identifier.
81 const invalidField = ^field(0)
83 // IsValid reports whether the field identifier is valid.
84 func (f field) IsValid() bool {
88 // Bytes returns the address of a []byte field in the struct.
89 func structPointer_Bytes(p structPointer, f field) *[]byte {
90 return (*[]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
93 // BytesSlice returns the address of a [][]byte field in the struct.
94 func structPointer_BytesSlice(p structPointer, f field) *[][]byte {
95 return (*[][]byte)(unsafe.Pointer(uintptr(p) + uintptr(f)))
98 // Bool returns the address of a *bool field in the struct.
99 func structPointer_Bool(p structPointer, f field) **bool {
100 return (**bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
103 // BoolVal returns the address of a bool field in the struct.
104 func structPointer_BoolVal(p structPointer, f field) *bool {
105 return (*bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
108 // BoolSlice returns the address of a []bool field in the struct.
109 func structPointer_BoolSlice(p structPointer, f field) *[]bool {
110 return (*[]bool)(unsafe.Pointer(uintptr(p) + uintptr(f)))
113 // String returns the address of a *string field in the struct.
114 func structPointer_String(p structPointer, f field) **string {
115 return (**string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
118 // StringVal returns the address of a string field in the struct.
119 func structPointer_StringVal(p structPointer, f field) *string {
120 return (*string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
123 // StringSlice returns the address of a []string field in the struct.
124 func structPointer_StringSlice(p structPointer, f field) *[]string {
125 return (*[]string)(unsafe.Pointer(uintptr(p) + uintptr(f)))
128 // ExtMap returns the address of an extension map field in the struct.
129 func structPointer_Extensions(p structPointer, f field) *XXX_InternalExtensions {
130 return (*XXX_InternalExtensions)(unsafe.Pointer(uintptr(p) + uintptr(f)))
133 func structPointer_ExtMap(p structPointer, f field) *map[int32]Extension {
134 return (*map[int32]Extension)(unsafe.Pointer(uintptr(p) + uintptr(f)))
137 // NewAt returns the reflect.Value for a pointer to a field in the struct.
138 func structPointer_NewAt(p structPointer, f field, typ reflect.Type) reflect.Value {
139 return reflect.NewAt(typ, unsafe.Pointer(uintptr(p)+uintptr(f)))
142 // SetStructPointer writes a *struct field in the struct.
143 func structPointer_SetStructPointer(p structPointer, f field, q structPointer) {
144 *(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f))) = q
147 // GetStructPointer reads a *struct field in the struct.
148 func structPointer_GetStructPointer(p structPointer, f field) structPointer {
149 return *(*structPointer)(unsafe.Pointer(uintptr(p) + uintptr(f)))
152 // StructPointerSlice the address of a []*struct field in the struct.
153 func structPointer_StructPointerSlice(p structPointer, f field) *structPointerSlice {
154 return (*structPointerSlice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
157 // A structPointerSlice represents a slice of pointers to structs (themselves submessages or groups).
158 type structPointerSlice []structPointer
160 func (v *structPointerSlice) Len() int { return len(*v) }
161 func (v *structPointerSlice) Index(i int) structPointer { return (*v)[i] }
162 func (v *structPointerSlice) Append(p structPointer) { *v = append(*v, p) }
164 // A word32 is the address of a "pointer to 32-bit value" field.
167 // IsNil reports whether *v is nil.
168 func word32_IsNil(p word32) bool {
172 // Set sets *v to point at a newly allocated word set to x.
173 func word32_Set(p word32, o *Buffer, x uint32) {
174 if len(o.uint32s) == 0 {
175 o.uint32s = make([]uint32, uint32PoolSize)
179 o.uint32s = o.uint32s[1:]
182 // Get gets the value pointed at by *v.
183 func word32_Get(p word32) uint32 {
187 // Word32 returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
188 func structPointer_Word32(p structPointer, f field) word32 {
189 return word32((**uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
192 // A word32Val is the address of a 32-bit value field.
193 type word32Val *uint32
196 func word32Val_Set(p word32Val, x uint32) {
200 // Get gets the value pointed at by p.
201 func word32Val_Get(p word32Val) uint32 {
205 // Word32Val returns the address of a *int32, *uint32, *float32, or *enum field in the struct.
206 func structPointer_Word32Val(p structPointer, f field) word32Val {
207 return word32Val((*uint32)(unsafe.Pointer(uintptr(p) + uintptr(f))))
210 // A word32Slice is a slice of 32-bit values.
211 type word32Slice []uint32
213 func (v *word32Slice) Append(x uint32) { *v = append(*v, x) }
214 func (v *word32Slice) Len() int { return len(*v) }
215 func (v *word32Slice) Index(i int) uint32 { return (*v)[i] }
217 // Word32Slice returns the address of a []int32, []uint32, []float32, or []enum field in the struct.
218 func structPointer_Word32Slice(p structPointer, f field) *word32Slice {
219 return (*word32Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))
222 // word64 is like word32 but for 64-bit values.
225 func word64_Set(p word64, o *Buffer, x uint64) {
226 if len(o.uint64s) == 0 {
227 o.uint64s = make([]uint64, uint64PoolSize)
231 o.uint64s = o.uint64s[1:]
234 func word64_IsNil(p word64) bool {
238 func word64_Get(p word64) uint64 {
242 func structPointer_Word64(p structPointer, f field) word64 {
243 return word64((**uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
246 // word64Val is like word32Val but for 64-bit values.
247 type word64Val *uint64
249 func word64Val_Set(p word64Val, o *Buffer, x uint64) {
253 func word64Val_Get(p word64Val) uint64 {
257 func structPointer_Word64Val(p structPointer, f field) word64Val {
258 return word64Val((*uint64)(unsafe.Pointer(uintptr(p) + uintptr(f))))
261 // word64Slice is like word32Slice but for 64-bit values.
262 type word64Slice []uint64
264 func (v *word64Slice) Append(x uint64) { *v = append(*v, x) }
265 func (v *word64Slice) Len() int { return len(*v) }
266 func (v *word64Slice) Index(i int) uint64 { return (*v)[i] }
268 func structPointer_Word64Slice(p structPointer, f field) *word64Slice {
269 return (*word64Slice)(unsafe.Pointer(uintptr(p) + uintptr(f)))