gprofng/src/Data_window.h

   1 /* Copyright (C) 2021-2024 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 */