smatch_address.c

   1 /*
   2  * Copyright (C) 2015 Oracle.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, see http://www.gnu.org/copyleft/gpl.txt
  16  */
  17
  18 #include "smatch.h"
  19 #include "smatch_slist.h"
  20 #include "smatch_extra.h"
  21
  22 static bool is_non_null_array(struct expression *expr)
  23 {
  24         struct symbol *type;
  25         struct symbol *sym;
  26         struct symbol *tmp;
  27         char *name;
  28         int i;
  29
  30         type = get_type(expr);
  31         if (!type || type->type != SYM_ARRAY)
  32                 return 0;
  33         if (expr->type == EXPR_SYMBOL)
  34                 return 1;
  35         if (implied_not_equal(expr, 0))
  36                 return 1;
  37
  38         /* verify that it's not the first member of the struct */
  39         if (expr->type != EXPR_DEREF || !expr->member)
  40                 return 0;
  41         name = expr_to_var_sym(expr, &sym);
  42         free_string(name);
  43         if (!name || !sym)
  44                 return 0;
  45         type = get_real_base_type(sym);
  46         if (!type || type->type != SYM_PTR)
  47                 return 0;
  48         type = get_real_base_type(type);
  49         if (type->type != SYM_STRUCT)
  50                 return 0;
  51
  52         i = 0;
  53         FOR_EACH_PTR(type->symbol_list, tmp) {
  54                 i++;
  55                 if (!tmp->ident)
  56                         continue;
  57                 if (strcmp(expr->member->name, tmp->ident->name) == 0) {
  58                         if (i == 1)
  59                                 return 0;
  60                         return 1;
  61                 }
  62         } END_FOR_EACH_PTR(tmp);
  63
  64         return 0;
  65 }
  66
  67 int get_address_rl(struct expression *expr, struct range_list **rl)
  68 {
  69         if (is_non_null_array(expr)) {
  70                 *rl = alloc_rl(array_min_sval, array_max_sval);
  71                 return 1;
  72         }
  73
  74         return 0;
  75 }