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Diffstat (limited to 'qpid/cpp/src/qpid/sys/MemoryMappedFile.h')
-rw-r--r-- | qpid/cpp/src/qpid/sys/MemoryMappedFile.h | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/qpid/cpp/src/qpid/sys/MemoryMappedFile.h b/qpid/cpp/src/qpid/sys/MemoryMappedFile.h new file mode 100644 index 0000000000..ecf38e98e6 --- /dev/null +++ b/qpid/cpp/src/qpid/sys/MemoryMappedFile.h @@ -0,0 +1,79 @@ +#ifndef QPID_SYS_MEMORYMAPPEDFILE_H +#define QPID_SYS_MEMORYMAPPEDFILE_H + +/* + * + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + * + */ +#include "qpid/CommonImportExport.h" +#include <string> + +namespace qpid { +namespace sys { + +class MemoryMappedFilePrivate; +/** + * Abstraction of memory mapping functionality + */ +class MemoryMappedFile { + public: + QPID_COMMON_EXTERN MemoryMappedFile(); + QPID_COMMON_EXTERN ~MemoryMappedFile(); + /** + * Opens a file that can be mapped by region into memory + */ + QPID_COMMON_EXTERN void open(const std::string& name, const std::string& directory); + /** + * Closes and removes the file that can be mapped by region into memory + */ + QPID_COMMON_EXTERN void close(); + /** + * Returns the page size + */ + QPID_COMMON_EXTERN size_t getPageSize(); + /** + * Load a portion of the file into memory + */ + QPID_COMMON_EXTERN char* map(size_t offset, size_t size); + /** + * Evict a portion of the file from memory + */ + QPID_COMMON_EXTERN void unmap(char* region, size_t size); + /** + * Flush any changes to a previously mapped region of the file + * back to disk + */ + QPID_COMMON_EXTERN void flush(char* region, size_t size); + /** + * Expand the capacity of the file + */ + QPID_COMMON_EXTERN void expand(size_t offset); + /** + * Returns true if memory mapping is supported, false otherwise + */ + QPID_COMMON_EXTERN static bool isSupported(); + private: + MemoryMappedFilePrivate* state; + + MemoryMappedFile(const MemoryMappedFile&); + MemoryMappedFile& operator=(const MemoryMappedFile&); +}; +}} // namespace qpid::sys + +#endif /*!QPID_SYS_MEMORYMAPPEDFILE_H*/ |