gdb/dwarf-index-common.c

   1 /* Things needed for both reading and writing DWARF indices.
   2
   3    Copyright (C) 1994-2019 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 "defs.h"
  21 #include "dwarf-index-common.h"
  22
  23 /* See dwarf-index-common.h.  */
  24
  25 hashval_t
  26 mapped_index_string_hash (int index_version, const void *p)
  27 {
  28   const unsigned char *str = (const unsigned char *) p;
  29   hashval_t r = 0;
  30   unsigned char c;
  31
  32   while ((c = *str++) != 0)
  33     {
  34       if (index_version >= 5)
  35         c = tolower (c);
  36       r = r * 67 + c - 113;
  37     }
  38
  39   return r;
  40 }
  41
  42 /* See dwarf-index-common.h.  */
  43
  44 uint32_t
  45 dwarf5_djb_hash (const char *str_)
  46 {
  47   const unsigned char *str = (const unsigned char *) str_;
  48
  49   /* Note: tolower here ignores UTF-8, which isn't fully compliant.
  50      See http://dwarfstd.org/ShowIssue.php?issue=161027.1.  */
  51
  52   uint32_t hash = 5381;
  53   while (int c = *str++)
  54     hash = hash * 33 + tolower (c);
  55   return hash;
  56 }