1 // Copyright 2015 The Chromium OS Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "buffer_writer.h"
6 
7 #include <string.h>
8 
9 #include <algorithm>
10 
11 namespace quipper {
12 
13 bool BufferWriter::WriteData(const void* src, const size_t size) {
14   // Do not write anything if the write needs to be truncated to avoid writing
15   // past the end of the file. The extra conditions here are in case of integer
16   // overflow.
17   if (offset_ + size > size_ || offset_ >= size_ || size > size_) return false;
18   memcpy(buffer_ + offset_, src, size);
19   offset_ += size;
20   return true;
21 }
22 
23 bool BufferWriter::WriteString(const string& str, const size_t size) {
24   // Make sure there is enough space left in the buffer.
25   size_t write_size = std::min(str.size(), size);
26   if (offset_ + size > size_ || !WriteData(str.c_str(), write_size))
27     return false;
28 
29   // Write the padding, if any. Note that the offset has been updated by
30   // WriteData.
31   memset(buffer_ + offset_, 0, size - write_size);
32   offset_ += size - write_size;
33   return true;
34 }
35 
36 bool BufferWriter::CanWriteSize(size_t data_size) {
37   return Tell() + data_size <= size();
38 }
39 
40 }  // namespace quipper
41