1  /* Copyright (C) 2021-2023 Free Software Foundation, Inc.
       2     Contributed by Oracle.
       3  
       4     This file is part of GNU Binutils.
       5  
       6     This program is free software; you can redistribute it and/or modify
       7     it under the terms of the GNU General Public License as published by
       8     the Free Software Foundation; either version 3, or (at your option)
       9     any later version.
      10  
      11     This program is distributed in the hope that it will be useful,
      12     but WITHOUT ANY WARRANTY; without even the implied warranty of
      13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      14     GNU General Public License for more details.
      15  
      16     You should have received a copy of the GNU General Public License
      17     along with this program; if not, write to the Free Software
      18     Foundation, 51 Franklin Street - Fifth Floor, Boston,
      19     MA 02110-1301, USA.  */
      20  
      21  #ifndef _DATA_WINDOW_H
      22  #define _DATA_WINDOW_H
      23  
      24  // The Data_window class hiearchy is used to access raw data in the
      25  // experiment record.
      26  //
      27  // The Data_window base class implements a set of windows into a raw data file.
      28  // It is responsible for mapping and unmapping regions of the file as
      29  // requested by other levels inside of the DBE.
      30  
      31  #include "util.h"
      32  
      33  class Data_window
      34  {
      35  public:
      36  
      37    // Span in data file
      38    typedef struct
      39    {
      40      int64_t offset; // file offset
      41      int64_t length; // span length
      42    } Span;
      43  
      44    Data_window (char *filename);
      45    ~Data_window ();
      46  
      47    // Return address of "offset" byte of window for "length" bytes.
      48    // Return 0 on error or locked.
      49    void *bind (Span *span, int64_t minSize);
      50    void *bind (int64_t file_offset, int64_t minSize);
      51    void *get_data (int64_t offset, int64_t size, void *datap);
      52    int64_t get_buf_size ();
      53    int64_t copy_to_file (int f, int64_t offset, int64_t size);
      54  
      55    bool not_opened ()            { return !opened; }
      56    off64_t get_fsize ()          { return fsize; }
      57  
      58    template <typename Key_t> inline Key_t
      59    get_align_val (Key_t *vp)
      60    {
      61      if (sizeof (Key_t) <= sizeof (int))
      62        return *vp;
      63      // 64-bit value can have a wrong alignment
      64      Key_t val = (Key_t) 0;
      65      uint32_t *p1 = (uint32_t *) vp;
      66      uint32_t *p2 = (uint32_t*) (&val);
      67      p2[0] = p1[0];
      68      p2[1] = p1[1];
      69      return val;
      70    }
      71  
      72    template <typename Key_t> inline Key_t
      73    decode (Key_t &v)
      74    {
      75      Key_t val = get_align_val (&v);
      76      if (need_swap_endian)
      77        swapByteOrder (&val, sizeof (val));
      78      return val;
      79    }
      80  
      81    bool need_swap_endian;
      82    char *fname;          // file name
      83  
      84  protected:
      85    int fd;               // file descriptor
      86    bool mmap_on_file;
      87  
      88  private:
      89    long page_size;       // used in mmap()
      90    bool use_mmap;
      91    bool opened;
      92    int64_t fsize;        // file size
      93    void *base;           // current window
      94    int64_t woffset;      // offset of current window
      95    int64_t wsize;        // size of current window
      96    int64_t basesize;     // size of allocated window
      97  };
      98  
      99  #endif /* _DATA_WINDOW_H */