check_input_free_device.c

   1 /*
   2  * smatch/check_input_free_device.c
   3  *
   4  * Copyright (C) 2010 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 /*
  11  * Don't call input_free_device() after calling
  12  * input_unregister_device()
  13  *
  14  */
  15
  16 #include "smatch.h"
  17 #include "smatch_slist.h"
  18
  19 STATE(no_free);
  20 STATE(ok);
  21
  22 static int my_id;
  23
  24 static void match_assign(struct expression *expr)
  25 {
  26         if (get_state_expr(my_id, expr->left)) {
  27                 set_state_expr(my_id, expr->left, &ok);
  28         }
  29 }
  30
  31 static void match_input_unregister(const char *fn, struct expression *expr, void *data)
  32 {
  33         struct expression *arg;
  34
  35         arg = get_argument_from_call_expr(expr->args, 0);
  36         set_state_expr(my_id, arg, &no_free);
  37 }
  38
  39 static void match_input_free(const char *fn, struct expression *expr, void *data)
  40 {
  41         struct expression *arg;
  42         struct sm_state *sm;
  43
  44         arg = get_argument_from_call_expr(expr->args, 0);
  45         sm = get_sm_state_expr(my_id, arg);
  46         if (!sm)
  47                 return;
  48         if (!slist_has_state(sm->possible, &no_free))
  49                 return;
  50         sm_msg("error: don't call input_free_device() after input_unregister_device()");
  51 }
  52
  53 void check_input_free_device(int id)
  54 {
  55         my_id = id;
  56         if (option_project != PROJ_KERNEL)
  57                 return;
  58         add_hook(&match_assign, ASSIGNMENT_HOOK);
  59         add_function_hook("input_unregister_device", &match_input_unregister, NULL);
  60         add_function_hook("input_free_device", &match_input_free, NULL);
  61 }