Extract disk opening functions to separate module

src/blockstore_disk.h

@@ -0,0 +1,42 @@
+// Copyright (c) Vitaliy Filippov, 2019+
+// License: VNPL-1.1 (see README.md for details)
+
+#pragma once
+
+#include <stdint.h>
+
+#include <string>
+#include <map>
+
+struct blockstore_disk_t
+{
+    std::string data_device, meta_device, journal_device;
+    uint32_t data_block_size;
+    uint64_t cfg_journal_size, cfg_data_size;
+    // Required write alignment and journal/metadata/data areas' location alignment
+    uint32_t disk_alignment = 4096;
+    // Journal block size - minimum_io_size of the journal device is the best choice
+    uint64_t journal_block_size = 4096;
+    // Metadata block size - minimum_io_size of the metadata device is the best choice
+    uint64_t meta_block_size = 4096;
+    // Sparse write tracking granularity. 4 KB is a good choice. Must be a multiple of disk_alignment
+    uint64_t bitmap_granularity = 4096;
+    // By default, Blockstore locks all opened devices exclusively. This option can be used to disable locking
+    bool disable_flock = false;
+
+    int meta_fd = -1, data_fd = -1, journal_fd = -1;
+    uint64_t meta_offset, meta_device_sect, meta_device_size, meta_len;
+    uint64_t data_offset, data_device_sect, data_device_size, data_len;
+    uint64_t journal_offset, journal_device_sect, journal_device_size, journal_len;
+
+    uint32_t block_order;
+    uint64_t block_count;
+    uint32_t clean_entry_bitmap_size = 0, clean_entry_size = 0;
+
+    void parse_config(std::map<std::string, std::string> & config);
+    void open_data();
+    void open_meta();
+    void open_journal();
+    void calc_lengths();
+    void close_all();
+};