xref: /netbsd-src/external/gpl3/binutils/dist/gprofng/src/DataStream.cc (revision cb63e24e8d6aae7ddac1859a9015f48b1d8bd90e)
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 #include "config.h"
22 #include "util.h"
23 #include "DataStream.h"
24 #include "debug.h"
25 
DataStream(char * filename)26 DataStream::DataStream (char *filename) : Data_window (filename)
27 {
28   set_span (0, -1);
29 }
30 
~DataStream()31 DataStream::~DataStream () { }
32 
33 void
set_span(int64_t f_offset,int64_t sz)34 DataStream::set_span (int64_t f_offset, int64_t sz)
35 {
36   span_offset = 0;
37   span_fileoffset = f_offset;
38   int64_t fsz = get_fsize ();
39   span_size = sz == -1 ? fsz : sz;
40   if (span_fileoffset >= fsz)
41     span_fileoffset = fsz;
42   if (span_size > fsz - span_fileoffset)
43     span_size = fsz - span_fileoffset;
44 }
45 
46 int64_t
read(void * buf,int64_t len)47 DataStream::read (void *buf, int64_t len)
48 {
49   if (len > span_size - span_offset)
50     len = span_size - span_offset;
51   int64_t off = span_offset + span_fileoffset;
52   span_offset += len;
53   get_data (off, len, buf);
54   return len;
55 }
56