smatch_returns.c

   1 /*
   2  * Copyright (C) 2011 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_slist.h"
  20 #include "smatch_extra.h"
  21
  22 int RETURN_ID;
  23
  24 struct return_states_callback {
  25         void (*callback)(void);
  26 };
  27 ALLOCATOR(return_states_callback, "return states callbacks");
  28 DECLARE_PTR_LIST(callback_list, struct return_states_callback);
  29 static struct callback_list *callback_list;
  30
  31 static struct stree_stack *return_stree_stack;
  32 static struct stree *all_return_states;
  33
  34 void all_return_states_hook(void (*callback)(void))
  35 {
  36         struct return_states_callback *rs_cb = __alloc_return_states_callback(0);
  37
  38         rs_cb->callback = callback;
  39         add_ptr_list(&callback_list, rs_cb);
  40 }
  41
  42 static void call_hooks(void)
  43 {
  44         struct return_states_callback *rs_cb;
  45         struct stree *orig;
  46
  47         orig = __swap_cur_stree(all_return_states);
  48         FOR_EACH_PTR(callback_list, rs_cb) {
  49                 rs_cb->callback();
  50         } END_FOR_EACH_PTR(rs_cb);
  51         __swap_cur_stree(orig);
  52 }
  53
  54 static void match_return(int return_id, char *return_ranges, struct expression *expr)
  55 {
  56         struct stree *stree;
  57
  58         stree = clone_stree(__get_cur_stree());
  59         merge_stree_no_pools(&all_return_states, stree);
  60         push_stree(&return_stree_stack, stree);
  61 }
  62
  63 static void match_end_func(struct symbol *sym)
  64 {
  65         /*
  66          * FIXME: either this isn't needed or we need to copy a stree into the
  67          * return_stree_stack as well.
  68          */
  69         merge_stree(&all_return_states, __get_cur_stree());
  70         call_hooks();
  71 }
  72
  73 struct stree *get_all_return_states(void)
  74 {
  75         return all_return_states;
  76 }
  77
  78 struct stree_stack *get_all_return_strees(void)
  79 {
  80         return return_stree_stack;
  81 }
  82
  83 static void free_resources(struct symbol *sym)
  84 {
  85         free_stree(&all_return_states);
  86         free_stack_and_strees(&return_stree_stack);
  87 }
  88
  89 void register_returns_early(int id)
  90 {
  91         RETURN_ID = id;
  92
  93         set_dynamic_states(RETURN_ID);
  94         add_split_return_callback(match_return);
  95 }
  96
  97 void register_returns(int id)
  98 {
  99         add_hook(&match_end_func, END_FUNC_HOOK);
 100         add_function_data((unsigned long *)&all_return_states);
 101         add_function_data((unsigned long *)&return_stree_stack);
 102         add_hook(&free_resources, AFTER_FUNC_HOOK);
 103 }