src/symlist.c

   1 /* Lists of symbols for Bison
   2    Copyright (C) 2002  Free Software Foundation, Inc.
   3
   4    This file is part of Bison, the GNU Compiler Compiler.
   5
   6    Bison 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 2, or (at your option)
   9    any later version.
  10
  11    Bison 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 Bison; see the file COPYING.  If not, write to
  18    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include "system.h"
  22 #include "complain.h"
  23 #include "symlist.h"
  24
  25
  26 /*----------------------------------------------.
  27 | Create a list containing SYMBOL at LOCATION.  |
  28 `----------------------------------------------*/
  29
  30 symbol_list_t *
  31 symbol_list_new (symbol_t *sym, location_t location)
  32 {
  33   symbol_list_t *res = XMALLOC (symbol_list_t, 1);
  34   res->next = NULL;
  35   res->sym = sym;
  36   res->location = location;
  37   res->action = NULL;
  38   res->ruleprec = NULL;
  39   res->dprec = 0;
  40   res->merger = 0;
  41   return res;
  42 }
  43
  44
  45 /*-----------------------------------------.
  46 | Prepend SYMBOL at LOCATION to the LIST.  |
  47 `-----------------------------------------*/
  48
  49 symbol_list_t *
  50 symbol_list_prepend (symbol_list_t *list,
  51                      symbol_t *symbol, location_t location)
  52 {
  53   symbol_list_t *res = symbol_list_new (symbol, location);
  54   res->next = list;
  55   return res;
  56 }
  57
  58
  59 /*-------------------------------------------------.
  60 | Free the LIST, but not the symbols it contains.  |
  61 `-------------------------------------------------*/
  62
  63 void
  64 symbol_list_free (symbol_list_t *list)
  65 {
  66   LIST_FREE (symbol_list_t, list);
  67 }
  68
  69
  70 /*--------------------.
  71 | Return its length.  |
  72 `--------------------*/
  73
  74 unsigned int
  75 symbol_list_length (symbol_list_t *list)
  76 {
  77   int res = 0;
  78   for (/* Nothing. */; list; list = list->next)
  79     ++res;
  80   return res;
  81 }
  82
  83
  84 /*--------------------------------------------------------------.
  85 | Get the data type (alternative in the union) of the value for |
  86 | symbol N in rule RULE.                                        |
  87 `--------------------------------------------------------------*/
  88
  89 struniq_t
  90 symbol_list_n_type_name_get (symbol_list_t *rule, location_t location, int n)
  91 {
  92   int i;
  93   symbol_list_t *rp;
  94
  95   if (n < 0)
  96     {
  97       complain_at (location, _("invalid $ value"));
  98       return NULL;
  99     }
 100
 101   rp = rule;
 102   i = 0;
 103
 104   while (i < n)
 105     {
 106       rp = rp->next;
 107       if (rp == NULL || rp->sym == NULL)
 108         {
 109           complain_at (location, _("invalid $ value"));
 110           return NULL;
 111         }
 112       ++i;
 113     }
 114
 115   return rp->sym->type_name;
 116 }