random_access_file_utils.cc revision 8f4b056427a9d2321e3aa4f21ca8ffb18b3e5ae6
1/* 2 * Copyright (C) 2009 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#include "base/unix_file/random_access_file_utils.h" 18 19#include <vector> 20 21#include "base/unix_file/random_access_file.h" 22 23namespace unix_file { 24 25bool CopyFile(const RandomAccessFile& src, RandomAccessFile* dst) { 26 // We don't call src->GetLength because some files (those in /proc, say) 27 // don't know how long they are. We just read until there's nothing left. 28 std::vector<char> buf(4096); 29 int64_t offset = 0; 30 int64_t n; 31 while ((n = src.Read(&buf[0], buf.size(), offset)) > 0) { 32 if (dst->Write(&buf[0], n, offset) != n) { 33 return false; 34 } 35 offset += n; 36 } 37 return n >= 0; 38} 39 40} // namespace unix_file 41