1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef ART_LIBELFFILE_STREAM_VECTOR_OUTPUT_STREAM_H_
18 #define ART_LIBELFFILE_STREAM_VECTOR_OUTPUT_STREAM_H_
19 
20 #include "output_stream.h"
21 
22 #include <string.h>
23 #include <string>
24 #include <vector>
25 
26 namespace art {
27 
28 class VectorOutputStream final : public OutputStream {
29  public:
30   VectorOutputStream(const std::string& location, std::vector<uint8_t>* vector);
31 
~VectorOutputStream()32   ~VectorOutputStream() override {}
33 
WriteFully(const void * buffer,size_t byte_count)34   bool WriteFully(const void* buffer, size_t byte_count) override {
35     if (static_cast<size_t>(offset_) == vector_->size()) {
36       const uint8_t* start = reinterpret_cast<const uint8_t*>(buffer);
37       vector_->insert(vector_->end(), &start[0], &start[byte_count]);
38       offset_ += byte_count;
39     } else {
40       off_t new_offset = offset_ + byte_count;
41       EnsureCapacity(new_offset);
42       memcpy(&(*vector_)[offset_], buffer, byte_count);
43       offset_ = new_offset;
44     }
45     return true;
46   }
47 
48   off_t Seek(off_t offset, Whence whence) override;
49 
Flush()50   bool Flush() override {
51     return true;
52   }
53 
54  private:
EnsureCapacity(off_t new_offset)55   void EnsureCapacity(off_t new_offset) {
56     if (new_offset > static_cast<off_t>(vector_->size())) {
57       vector_->resize(new_offset);
58     }
59   }
60 
61   off_t offset_;
62   std::vector<uint8_t>* const vector_;
63 
64   DISALLOW_COPY_AND_ASSIGN(VectorOutputStream);
65 };
66 
67 }  // namespace art
68 
69 #endif  // ART_LIBELFFILE_STREAM_VECTOR_OUTPUT_STREAM_H_
70