patch 4.0

src/share/ob_device_manager.h

@@ -0,0 +1,77 @@
+/**
+ * Copyright (c) 2021 OceanBase
+ * OceanBase CE is licensed under Mulan PubL v2.
+ * You can use this software according to the terms and conditions of the Mulan PubL v2.
+ * You may obtain a copy of Mulan PubL v2 at:
+ *          http://license.coscl.org.cn/MulanPubL-2.0
+ * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
+ * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
+ * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
+ * See the Mulan PubL v2 for more details.
+ */
+
+#ifndef SRC_LIBRARY_SRC_COMMON_STORAGE_OB_DEVICE_MANAGER_H_
+#define SRC_LIBRARY_SRC_COMMON_STORAGE_OB_DEVICE_MANAGER_H_
+
+#include "common/storage/ob_io_device.h"
+#include "lib/allocator/ob_fifo_allocator.h"
+#include "lib/hash/ob_hashmap.h"
+
+namespace oceanbase
+{
+namespace common
+{
+
+class ObDeviceManager
+{
+public: 
+  const static int MAX_DEVICE_INSTANCE = 20;
+  int init_devices_env();
+  void destroy();
+  static ObDeviceManager &get_instance();
+  
+  /*for object device, will return a new object to caller*/
+  /*ofs/local will share in upper logical*/
+  int get_device(const common::ObString& storage_info, 
+                 const common::ObString& storage_type_prefix,
+                 ObIODevice*& device_handle);
+  int release_device(common::ObIODevice*& device_handle);
+  //for test
+  int64_t get_device_cnt() {return device_count_;}
+  
+private:
+  ObDeviceManager();
+  ~ObDeviceManager() {}
+
+  struct ObDeviceInsInfo {
+    ObIODevice* device_; 
+    char        storage_info_[OB_MAX_URI_LENGTH];
+    int64_t     ref_cnt_;
+  };
+
+  /*notice: 
+  int the implement of hashtable, use the assign fun of class to copy key/value
+  but for string, assign fun just copy the pointer, so in device manager, should manager 
+  key mem space, in case upper lever release the pointer.
+  */
+  typedef common::hash::ObHashMap<ObString, ObDeviceInsInfo*> StoragInfoDeviceInfoMap;
+  typedef common::hash::ObHashMap<int64_t, ObDeviceInsInfo*> DeviceHandleDeviceInfoMap;
+
+  int alloc_device(ObDeviceInsInfo*& device_info, 
+                   const common::ObString& storage_info,
+                   const common::ObString& storage_type_prefix);
+ 
+  common::ObFIFOAllocator allocator_; /*alloc/free dynamic device mem*/
+  int32_t device_count_;
+  common::ObSpinLock lock_;  /*the manager is global used, so need lock to guarante thread safe*/
+  bool is_init_;
+  ObDeviceInsInfo device_ins_[MAX_DEVICE_INSTANCE];
+  StoragInfoDeviceInfoMap device_map_;
+  DeviceHandleDeviceInfoMap handle_map_; /*the key is a ObIODevice pointer, need cast when used*/
+};
+
+
+}
+}
+
+#endif