smatch_untracked_var.c

   1 /*
   2  * Copyright (C) 2022 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 /*
  19  * This just tracks local variables where we have saved the address to them.
  20  */
  21
  22 #include "smatch.h"
  23 #include "smatch_slist.h"
  24 #include "smatch_extra.h"
  25
  26 static int my_id;
  27
  28 STATE(untracked);
  29
  30 static void match_assign(struct expression *expr)
  31 {
  32         struct expression *right;
  33
  34         right = strip_expr(expr->right);
  35         if (!right || right->type != EXPR_PREOP || right->op != '&')
  36                 return;
  37         right = right->unop;
  38         if (!right || right->type != EXPR_SYMBOL)
  39                 return;
  40         set_state_expr(my_id, right, &untracked);
  41 }
  42
  43 bool is_untracked(struct expression *expr)
  44 {
  45         if (get_state_expr(my_id, expr))
  46                 return true;
  47         return false;
  48 }
  49
  50 void register_untracked_var(int id)
  51 {
  52         my_id = id;
  53
  54         add_hook(match_assign, ASSIGNMENT_HOOK);
  55 }