1 // Copyright 2017 The Android Open Source Project
2 //
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 
15 #pragma once
16 
17 #include "android/base/containers/SmallVector.h"
18 #include "android/base/files/MemStream.h"
19 #include "android/base/files/Stream.h"
20 #include "android/base/TypeTraits.h"
21 
22 #include <string>
23 #include <vector>
24 
25 namespace android {
26 namespace base {
27 
28 //
29 // Save/load operations for different types.
30 //
31 
32 void saveStream(Stream* stream, const MemStream& memStream);
33 void loadStream(Stream* stream, MemStream* memStream);
34 
35 void saveBufferRaw(Stream* stream, char* buffer, uint32_t len);
36 bool loadBufferRaw(Stream* stream, char* buffer);
37 
38 template <class T, class = enable_if<std::is_standard_layout<T>>>
saveBuffer(Stream * stream,const std::vector<T> & buffer)39 void saveBuffer(Stream* stream, const std::vector<T>& buffer) {
40     stream->putBe32(buffer.size());
41     stream->write(buffer.data(), sizeof(T) * buffer.size());
42 }
43 
44 template <class T, class = enable_if<std::is_standard_layout<T>>>
loadBuffer(Stream * stream,std::vector<T> * buffer)45 bool loadBuffer(Stream* stream, std::vector<T>* buffer) {
46     auto len = stream->getBe32();
47     buffer->resize(len);
48     int ret = (int)stream->read(buffer->data(), len * sizeof(T));
49     return ret == len * sizeof(T);
50 }
51 
52 template <class T, class = enable_if<std::is_standard_layout<T>>>
saveBuffer(Stream * stream,const SmallVector<T> & buffer)53 void saveBuffer(Stream* stream, const SmallVector<T>& buffer) {
54     stream->putBe32(buffer.size());
55     stream->write(buffer.data(), sizeof(T) * buffer.size());
56 }
57 
58 template <class T, class = enable_if<std::is_standard_layout<T>>>
loadBuffer(Stream * stream,SmallVector<T> * buffer)59 bool loadBuffer(Stream* stream, SmallVector<T>* buffer) {
60     auto len = stream->getBe32();
61     buffer->clear();
62     buffer->resize_noinit(len);
63     int ret = (int)stream->read(buffer->data(), len * sizeof(T));
64     return ret == len * sizeof(T);
65 }
66 
67 template <class T, class SaveFunc>
saveBuffer(Stream * stream,const std::vector<T> & buffer,SaveFunc && saver)68 void saveBuffer(Stream* stream, const std::vector<T>& buffer, SaveFunc&& saver) {
69     stream->putBe32(buffer.size());
70     for (const auto& val : buffer) {
71         saver(stream, val);
72     }
73 }
74 
75 template <class T>
saveBuffer(Stream * stream,const T * buffer,size_t numElts)76 void saveBuffer(Stream* stream, const T* buffer, size_t numElts) {
77     stream->putBe32(numElts);
78     stream->write(buffer, sizeof(T) * numElts);
79 }
80 
81 template <class T>
loadBufferPtr(Stream * stream,T * out)82 void loadBufferPtr(Stream* stream, T* out) {
83     auto len = stream->getBe32();
84     stream->read(out, len * sizeof(T));
85 }
86 
87 template <class T, class LoadFunc>
loadBuffer(Stream * stream,std::vector<T> * buffer,LoadFunc && loader)88 void loadBuffer(Stream* stream, std::vector<T>* buffer, LoadFunc&& loader) {
89     auto len = stream->getBe32();
90     buffer->clear();
91     buffer->reserve(len);
92     for (uint32_t i = 0; i < len; i++) {
93         buffer->emplace_back(loader(stream));
94     }
95 }
96 
97 template <class Collection, class SaveFunc>
saveCollection(Stream * stream,const Collection & c,SaveFunc && saver)98 void saveCollection(Stream* stream, const Collection& c, SaveFunc&& saver) {
99     stream->putBe32(c.size());
100     for (const auto& val : c) {
101         saver(stream, val);
102     }
103 }
104 
105 template <class Collection, class LoadFunc>
loadCollection(Stream * stream,Collection * c,LoadFunc && loader)106 void loadCollection(Stream* stream, Collection* c, LoadFunc&& loader) {
107     const int size = stream->getBe32();
108     for (int i = 0; i < size; ++i) {
109         c->emplace(loader(stream));
110     }
111 }
112 
113 void saveStringArray(Stream* stream, const char* const* strings, uint32_t count);
114 std::vector<std::string> loadStringArray(Stream* stream);
115 
116 }  // namespace base
117 }  // namespace android
118