smatch_kernel_atomic_dec_test_path.c

   1 /*
   2  * Copyright (C) 2016 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(zero_path);
  25
  26 static void handle_test_functions(struct expression *expr)
  27 {
  28         struct expression *tmp;
  29         struct statement *stmt;
  30         int count = 0;
  31
  32         if (expr->type != EXPR_CALL ||
  33             expr->fn->type != EXPR_SYMBOL ||
  34             !expr->fn->symbol_name)
  35                 return;
  36         if (!strstr(expr->fn->symbol_name->name, "test"))
  37                 return;
  38
  39         while ((tmp = expr_get_parent_expr(expr))) {
  40                 expr = tmp;
  41                 if (count++ > 5)
  42                         break;
  43         }
  44
  45         stmt = expr_get_parent_stmt(expr);
  46         if (!stmt || stmt->type != STMT_IF)
  47                 return;
  48
  49         set_true_false_states(my_id, "dec_path", NULL, &zero_path, NULL);
  50 }
  51
  52 static void match_dec(struct expression *expr, const char *name, struct symbol *sym)
  53 {
  54         handle_test_functions(expr);
  55 }
  56
  57 int on_atomic_dec_path(void)
  58 {
  59         return get_state(my_id, "dec_path", NULL) == &zero_path;
  60 }
  61
  62 void register_kernel_atomic_dec_test_path(int id)
  63 {
  64         my_id = id;
  65
  66         if (option_project != PROJ_KERNEL)
  67                 return;
  68
  69         add_refcount_dec_hook(&match_dec);
  70 }