smatch_links.c

   1 /*
   2  * Copyright (C) 2014 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 /*
  19  * Some helper functions for managing links.
  20  *
  21  */
  22
  23 #include "smatch.h"
  24 #include "smatch_slist.h"
  25
  26 static struct smatch_state *alloc_link(struct var_sym_list *links)
  27 {
  28         struct smatch_state *state;
  29         static char buf[256];
  30         struct var_sym *tmp;
  31         int i;
  32
  33         state = __alloc_smatch_state(0);
  34
  35         i = 0;
  36         FOR_EACH_PTR(links, tmp) {
  37                 if (!i++) {
  38                         snprintf(buf, sizeof(buf), "%s", tmp->var);
  39                 } else {
  40                         append(buf, ", ", sizeof(buf));
  41                         append(buf, tmp->var, sizeof(buf));
  42                 }
  43         } END_FOR_EACH_PTR(tmp);
  44
  45         state->name = alloc_sname(buf);
  46         state->data = links;
  47         return state;
  48 }
  49
  50 struct smatch_state *merge_link_states(struct smatch_state *s1, struct smatch_state *s2)
  51 {
  52         struct var_sym_list *new_links;
  53
  54         if (s1 == &undefined)
  55                 return s2;
  56         if (s2 == &undefined)
  57                 return s1;
  58
  59         if (var_sym_lists_equiv(s1->data, s2->data))
  60                 return s1;
  61
  62         new_links = clone_var_sym_list(s1->data);
  63         merge_var_sym_list(&new_links, s2->data);
  64
  65         return alloc_link(new_links);
  66 }
  67
  68 void store_link(int link_id, const char *var, struct symbol *sym, const char *link_name, struct symbol *link_sym)
  69 {
  70
  71         struct smatch_state *old_state;
  72         struct var_sym_list *links;
  73
  74         if (!cur_func_sym)
  75                 return;
  76
  77         old_state = get_state(link_id, var, sym);
  78         if (old_state)
  79                 links = clone_var_sym_list(old_state->data);
  80         else
  81                 links = NULL;
  82
  83         add_var_sym(&links, link_name, link_sym);
  84         set_state(link_id, var, sym, alloc_link(links));
  85 }
  86
  87 static void match_link_modify(struct sm_state *sm, struct expression *mod_expr)
  88 {
  89         struct var_sym_list *links;
  90         struct var_sym *tmp;
  91
  92         links = sm->state->data;
  93
  94         FOR_EACH_PTR(links, tmp) {
  95                 set_state(sm->owner - 1, tmp->var, tmp->sym, &undefined);
  96         } END_FOR_EACH_PTR(tmp);
  97         set_state(sm->owner, sm->name, sm->sym, &undefined);
  98 }
  99
 100 void set_up_link_functions(int id, int link_id)
 101 {
 102         if (id + 1 != link_id) {
 103                 printf("FATAL ERROR: links need to be registered directly after the check");
 104                 exit(1);
 105         }
 106
 107         add_merge_hook(link_id, &merge_link_states);
 108         add_modification_hook(link_id, &match_link_modify);
 109         // free link at the end of function
 110 }
 111