gdbsupport/scoped_mmap.cc

   1 /* scoped_mmap, automatically unmap files
   2
   3    Copyright (C) 2018-2024 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "scoped_mmap.h"
  21 #include "scoped_fd.h"
  22 #include "gdbsupport/filestuff.h"
  23
  24 #ifdef HAVE_SYS_MMAN_H
  25
  26 scoped_mmap
  27 mmap_file (const char *filename)
  28 {
  29   scoped_fd fd = gdb_open_cloexec (filename, O_RDONLY, 0);
  30   if (fd.get () < 0)
  31     perror_with_name (("open"));
  32
  33   off_t size = lseek (fd.get (), 0, SEEK_END);
  34   if (size < 0)
  35     perror_with_name (("lseek"));
  36
  37   /* We can't map an empty file.  */
  38   if (size == 0)
  39     error (_("file to mmap is empty"));
  40
  41   scoped_mmap mmapped_file (nullptr, size, PROT_READ, MAP_PRIVATE, fd.get (), 0);
  42   if (mmapped_file.get () == MAP_FAILED)
  43     perror_with_name (("mmap"));
  44
  45   return mmapped_file;
  46 }
  47
  48 #endif /* HAVE_SYS_MMAN_H */