1 // Copyright (c) 2012 The Chromium 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 #ifndef LIBRARIES_NACL_IO_INODE_POOL_H_ 6 #define LIBRARIES_NACL_IO_INODE_POOL_H_ 7 8 #include <stdlib.h> 9 #include <vector> 10 11 #include "nacl_io/osstat.h" 12 #include "pthread.h" 13 #include "sdk_util/auto_lock.h" 14 15 namespace nacl_io { 16 17 class INodePool { 18 public: INodePool()19 INodePool() : num_nodes_(0), max_nodes_(0) {} 20 Acquire()21 ino_t Acquire() { 22 AUTO_LOCK(lock_); 23 const int INO_CNT = 8; 24 25 // If we run out of INO numbers, then allocate 8 more 26 if (inos_.size() == 0) { 27 max_nodes_ += INO_CNT; 28 // Add eight more to the stack in reverse order, offset by 1 29 // since '0' refers to no INO. 30 for (int a = 0; a < INO_CNT; a++) { 31 inos_.push_back(max_nodes_ - a); 32 } 33 } 34 35 // Return the INO at the top of the stack. 36 int val = inos_.back(); 37 inos_.pop_back(); 38 num_nodes_++; 39 return val; 40 } 41 Release(ino_t ino)42 void Release(ino_t ino) { 43 AUTO_LOCK(lock_); 44 inos_.push_back(ino); 45 num_nodes_--; 46 } 47 size()48 size_t size() const { return num_nodes_; } capacity()49 size_t capacity() const { return max_nodes_; } 50 51 private: 52 size_t num_nodes_; 53 size_t max_nodes_; 54 std::vector<ino_t> inos_; 55 sdk_util::SimpleLock lock_; 56 }; 57 58 } // namespace nacl_io 59 60 #endif // LIBRARIES_NACL_IO_INODE_POOL_H_ 61