check_assigned_expr.c

   1 /*
   2  * sparse/check_assigned_expr.c
   3  *
   4  * Copyright (C) 2009 Dan Carpenter.
   5  *
   6  * Licensed under the Open Software License version 1.1
   7  *
   8  */
   9
  10 /*
  11  * This is not a check.  It just saves an struct expression pointer
  12  * whenever something is assigned.  This can be used later on by other scripts.
  13  */
  14
  15 #include "smatch.h"
  16 #include "smatch_slist.h"
  17
  18 int check_assigned_expr_id;
  19 static int my_id;
  20
  21 struct expression *get_assigned_expr(struct expression *expr)
  22 {
  23         struct smatch_state *state;
  24
  25         state = get_state_expr(my_id, expr);
  26         if (!state)
  27                 return NULL;
  28         return (struct expression *)state->data;
  29 }
  30
  31 static struct smatch_state *alloc_my_state(struct expression *expr)
  32 {
  33         struct smatch_state *state;
  34         char *name;
  35
  36         state = __alloc_smatch_state(0);
  37         expr = strip_expr(expr);
  38         name = get_variable_from_expr_complex(expr, NULL);
  39         state->name = alloc_sname(name);
  40         free_string(name);
  41         state->data = expr;
  42         return state;
  43 }
  44
  45 static void match_assignment(struct expression *expr)
  46 {
  47         if (expr->op != '=')
  48                 return;
  49         set_state_expr(my_id, expr->left, alloc_my_state(expr->right));
  50 }
  51
  52 void check_assigned_expr(int id)
  53 {
  54         my_id = check_assigned_expr_id = id;
  55         add_hook(&match_assignment, ASSIGNMENT_HOOK);
  56 }