smatch_var_sym.c

   1 /*
   2  * Copyright (C) 2013 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
  20 ALLOCATOR(var_sym, "var_sym structs");
  21
  22 struct smatch_state *alloc_var_sym_state(const char *var, struct symbol *sym)
  23 {
  24         struct smatch_state *state;
  25
  26         state = __alloc_smatch_state(0);
  27         state->name = alloc_string(var);
  28         state->data = alloc_var_sym(var, sym);
  29         return state;
  30 }
  31
  32 struct var_sym *alloc_var_sym(const char *var, struct symbol *sym)
  33 {
  34         struct var_sym *tmp;
  35
  36         tmp = __alloc_var_sym(0);
  37         tmp->var = alloc_string(var);
  38         tmp->sym = sym;
  39         return tmp;
  40 }
  41
  42 struct var_sym_list *expr_to_vsl(struct expression *expr)
  43 {
  44         struct var_sym_list *ret = NULL;
  45         struct var_sym_list *more;
  46         char *var;
  47         struct symbol *sym;
  48
  49         expr = strip_expr(expr);
  50         if (!expr)
  51                 return NULL;
  52
  53         if (expr->type == EXPR_BINOP ||
  54             expr->type == EXPR_LOGICAL ||
  55             expr->type == EXPR_COMPARE) {
  56                 struct var_sym_list *left, *right;
  57
  58                 left = expr_to_vsl(expr->left);
  59                 right = expr_to_vsl(expr->right);
  60                 ret = combine_var_sym_lists(left, right);
  61                 free_var_syms_and_list(&left);
  62                 free_var_syms_and_list(&right);
  63                 return ret;
  64         }
  65
  66         var = expr_to_var_sym(expr, &sym);
  67         if (var && sym)
  68                 add_var_sym(&ret, var, sym);
  69
  70
  71         // handle "*(foo[bar])" I guess */
  72         if (expr->type == EXPR_PREOP && expr->op == '*') {
  73                 more = expr_to_vsl(expr->unop);
  74                 return combine_var_sym_lists(ret, more);
  75         }
  76
  77         if (expr->type == EXPR_DEREF) {
  78                 more = expr_to_vsl(expr->deref);
  79                 return combine_var_sym_lists(ret, more);
  80         }
  81
  82         return ret;
  83 }
  84
  85 int cmp_var_sym(const struct var_sym *a, const struct var_sym *b)
  86 {
  87         int ret;
  88
  89         if (a == b)
  90                 return 0;
  91         if (!b)
  92                 return -1;
  93         if (!a)
  94                 return 1;
  95
  96         ret = strcmp(a->var, b->var);
  97         if (ret < 0)
  98                 return -1;
  99         if (ret > 0)
 100                 return 1;
 101
 102         if (!b->sym && a->sym)
 103                 return -1;
 104         if (!a->sym && b->sym)
 105                 return 1;
 106         if (a->sym < b->sym)
 107                 return -1;
 108         if (a->sym > b->sym)
 109                 return 1;
 110
 111         return 0;
 112 }
 113
 114 void add_var_sym(struct var_sym_list **list, const char *var, struct symbol *sym)
 115 {
 116         struct var_sym *tmp, *new;
 117
 118         if (in_var_sym_list(*list, var, sym))
 119                 return;
 120         new = alloc_var_sym(var, sym);
 121
 122         FOR_EACH_PTR(*list, tmp) {
 123                 if (cmp_var_sym(tmp, new) < 0)
 124                         continue;
 125                 else if (cmp_var_sym(tmp, new) == 0) {
 126                         return;
 127                 } else {
 128                         INSERT_CURRENT(new, tmp);
 129                         return;
 130                 }
 131         } END_FOR_EACH_PTR(tmp);
 132         add_ptr_list(list, new);
 133 }
 134
 135 void add_var_sym_expr(struct var_sym_list **list, struct expression *expr)
 136 {
 137         char *var;
 138         struct symbol *sym;
 139
 140         var = expr_to_var_sym(expr, &sym);
 141         if (!var || !sym)
 142                 goto free;
 143         add_var_sym(list, var, sym);
 144 free:
 145         free_string(var);
 146 }
 147
 148 static void free_var_sym(struct var_sym *vs)
 149 {
 150         free_string(vs->var);
 151         __free_var_sym(vs);
 152 }
 153
 154 void del_var_sym(struct var_sym_list **list, const char *var, struct symbol *sym)
 155 {
 156         struct var_sym *tmp;
 157
 158         FOR_EACH_PTR(*list, tmp) {
 159                 if (tmp->sym == sym && strcmp(tmp->var, var) == 0) {
 160                         DELETE_CURRENT_PTR(tmp);
 161                         free_var_sym(tmp);
 162                         return;
 163                 }
 164         } END_FOR_EACH_PTR(tmp);
 165 }
 166
 167 int in_var_sym_list(struct var_sym_list *list, const char *var, struct symbol *sym)
 168 {
 169         struct var_sym *tmp;
 170
 171         FOR_EACH_PTR(list, tmp) {
 172                 if (tmp->sym == sym && strcmp(tmp->var, var) == 0)
 173                         return 1;
 174         } END_FOR_EACH_PTR(tmp);
 175         return 0;
 176 }
 177
 178 struct var_sym_list *clone_var_sym_list(struct var_sym_list *from_vsl)
 179 {
 180         struct var_sym *tmp, *clone_vs;
 181         struct var_sym_list *to_vsl = NULL;
 182
 183         FOR_EACH_PTR(from_vsl, tmp) {
 184                 clone_vs = alloc_var_sym(tmp->var, tmp->sym);
 185                 add_ptr_list(&to_vsl, clone_vs);
 186         } END_FOR_EACH_PTR(tmp);
 187         return to_vsl;
 188 }
 189
 190 void merge_var_sym_list(struct var_sym_list **dest, struct var_sym_list *src)
 191 {
 192         struct var_sym *tmp;
 193
 194         FOR_EACH_PTR(src, tmp) {
 195                 add_var_sym(dest, tmp->var, tmp->sym);
 196         } END_FOR_EACH_PTR(tmp);
 197 }
 198
 199 struct var_sym_list *combine_var_sym_lists(struct var_sym_list *one, struct var_sym_list *two)
 200 {
 201         struct var_sym_list *to_vsl;
 202
 203         to_vsl = clone_var_sym_list(one);
 204         merge_var_sym_list(&to_vsl, two);
 205         return to_vsl;
 206 }
 207
 208 int var_sym_lists_equiv(struct var_sym_list *one, struct var_sym_list *two)
 209 {
 210         struct var_sym *one_tmp, *two_tmp;
 211
 212         if (one == two)
 213                 return 1;
 214
 215         if (ptr_list_size((struct ptr_list *)one) != ptr_list_size((struct ptr_list *)two))
 216                 return 0;
 217
 218         PREPARE_PTR_LIST(one, one_tmp);
 219         PREPARE_PTR_LIST(two, two_tmp);
 220         for (;;) {
 221                 if (!one_tmp && !two_tmp)
 222                         return 1;
 223                 if (one_tmp->sym != two_tmp->sym)
 224                         return 0;
 225                 if (strcmp(one_tmp->var, two_tmp->var) != 0)
 226                         return 0;
 227                 NEXT_PTR_LIST(one_tmp);
 228                 NEXT_PTR_LIST(two_tmp);
 229         }
 230         FINISH_PTR_LIST(two_tmp);
 231         FINISH_PTR_LIST(one_tmp);
 232
 233         return 1;
 234 }
 235
 236 void free_var_sym_list(struct var_sym_list **list)
 237 {
 238         __free_ptr_list((struct ptr_list **)list);
 239 }
 240
 241 void free_var_syms_and_list(struct var_sym_list **list)
 242 {
 243         struct var_sym *tmp;
 244
 245         FOR_EACH_PTR(*list, tmp) {
 246                 free_var_sym(tmp);
 247         } END_FOR_EACH_PTR(tmp);
 248         free_var_sym_list(list);
 249 }
 250