smatch_refcount.c

   1 /*
   2  * Copyright (C) 2021 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_extra.h"
  20 #include "smatch_slist.h"
  21
  22 static int my_id;
  23
  24 STATE(inc);
  25 STATE(dec);
  26
  27 static void match_inc(struct expression *expr, const char *name, struct symbol *sym)
  28 {
  29         set_state(my_id, name, sym, &inc);
  30 }
  31
  32 static void match_dec(struct expression *expr, const char *name, struct symbol *sym)
  33 {
  34         set_state(my_id, name, sym, &dec);
  35 }
  36
  37 int was_inced(const char *name, struct symbol *sym)
  38 {
  39         if (has_possible_state(my_id, name, sym, &inc))
  40                 return true;
  41         return false;
  42 }
  43
  44 int refcount_was_inced_name_sym(const char *name, struct symbol *sym, const char *counter_str)
  45 {
  46         char buf[256];
  47
  48         snprintf(buf, sizeof(buf), "%s%s", name, counter_str);
  49         return was_inced(buf, sym);
  50 }
  51
  52 int refcount_was_inced(struct expression *expr, const char *counter_str)
  53 {
  54         char *name;
  55         struct symbol *sym;
  56         int ret = 0;
  57
  58         name = expr_to_var_sym(expr, &sym);
  59         if (!name || !sym)
  60                 goto free;
  61
  62         ret = refcount_was_inced_name_sym(name, sym, counter_str);
  63 free:
  64         free_string(name);
  65         return ret;
  66 }
  67
  68 void register_refcount(int id)
  69 {
  70         my_id = id;
  71
  72         if (option_project != PROJ_KERNEL)
  73                 return;
  74
  75         add_modification_hook(my_id, &set_undefined);
  76
  77         add_refcount_inc_hook(&match_inc);
  78         add_refcount_dec_hook(&match_dec);
  79 }