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 expression *unop;
  45         struct var_sym_list *ret = NULL;
  46         char *var;
  47         struct symbol *sym;
  48
  49         expr = strip_expr(expr);
  50         if (!expr)
  51                 return NULL;
  52
  53         if (expr_to_sym(expr))
  54                 goto one_var;
  55
  56         if (expr->type == EXPR_BINOP ||
  57             expr->type == EXPR_LOGICAL ||
  58             expr->type == EXPR_COMPARE) {
  59                 struct var_sym_list *left, *right;
  60
  61                 left = expr_to_vsl(expr->left);
  62                 right = expr_to_vsl(expr->right);
  63                 ret = combine_var_sym_lists(left, right);
  64                 free_var_syms_and_list(&left);
  65                 free_var_syms_and_list(&right);
  66                 return ret;
  67         }
  68
  69         // handle "*(foo[bar])" I guess */
  70         if ((expr->type == EXPR_PREOP && expr->op == '*')) {
  71                 unop = strip_expr(expr->unop);
  72
  73                 if (unop->type == EXPR_SYMBOL)
  74                         goto one_var;
  75                 return expr_to_vsl(unop);
  76         }
  77
  78         if (expr->type == EXPR_DEREF)
  79                 return expr_to_vsl(expr->deref);
  80
  81 one_var:
  82         var = expr_to_var_sym(expr, &sym);
  83         if (!var || !sym) {
  84                 free_string(var);
  85                 return NULL;
  86         }
  87         add_var_sym(&ret, var, sym);
  88         return ret;
  89 }
  90
  91 int cmp_var_sym(const struct var_sym *a, const struct var_sym *b)
  92 {
  93         int ret;
  94
  95         if (a == b)
  96                 return 0;
  97         if (!b)
  98                 return -1;
  99         if (!a)
 100                 return 1;
 101
 102         ret = strcmp(a->var, b->var);
 103         if (ret < 0)
 104                 return -1;
 105         if (ret > 0)
 106                 return 1;
 107
 108         if (!b->sym && a->sym)
 109                 return -1;
 110         if (!a->sym && b->sym)
 111                 return 1;
 112         if (a->sym < b->sym)
 113                 return -1;
 114         if (a->sym > b->sym)
 115                 return 1;
 116
 117         return 0;
 118 }
 119
 120 void add_var_sym(struct var_sym_list **list, const char *var, struct symbol *sym)
 121 {
 122         struct var_sym *tmp, *new;
 123
 124         if (in_var_sym_list(*list, var, sym))
 125                 return;
 126         new = alloc_var_sym(var, sym);
 127
 128         FOR_EACH_PTR(*list, tmp) {
 129                 if (cmp_var_sym(tmp, new) < 0)
 130                         continue;
 131                 else if (cmp_var_sym(tmp, new) == 0) {
 132                         return;
 133                 } else {
 134                         INSERT_CURRENT(new, tmp);
 135                         return;
 136                 }
 137         } END_FOR_EACH_PTR(tmp);
 138         add_ptr_list(list, new);
 139 }
 140
 141 void add_var_sym_expr(struct var_sym_list **list, struct expression *expr)
 142 {
 143         char *var;
 144         struct symbol *sym;
 145
 146         var = expr_to_var_sym(expr, &sym);
 147         if (!var || !sym)
 148                 goto free;
 149         add_var_sym(list, var, sym);
 150 free:
 151         free_string(var);
 152 }
 153
 154 static void free_var_sym(struct var_sym *vs)
 155 {
 156         free_string(vs->var);
 157         __free_var_sym(vs);
 158 }
 159
 160 void del_var_sym(struct var_sym_list **list, const char *var, struct symbol *sym)
 161 {
 162         struct var_sym *tmp;
 163
 164         FOR_EACH_PTR(*list, tmp) {
 165                 if (tmp->sym == sym && strcmp(tmp->var, var) == 0) {
 166                         DELETE_CURRENT_PTR(tmp);
 167                         free_var_sym(tmp);
 168                         return;
 169                 }
 170         } END_FOR_EACH_PTR(tmp);
 171 }
 172
 173 int in_var_sym_list(struct var_sym_list *list, const char *var, struct symbol *sym)
 174 {
 175         struct var_sym *tmp;
 176
 177         FOR_EACH_PTR(list, tmp) {
 178                 if (tmp->sym == sym && strcmp(tmp->var, var) == 0)
 179                         return 1;
 180         } END_FOR_EACH_PTR(tmp);
 181         return 0;
 182 }
 183
 184 struct var_sym_list *clone_var_sym_list(struct var_sym_list *from_vsl)
 185 {
 186         struct var_sym *tmp, *clone_vs;
 187         struct var_sym_list *to_vsl = NULL;
 188
 189         FOR_EACH_PTR(from_vsl, tmp) {
 190                 clone_vs = alloc_var_sym(tmp->var, tmp->sym);
 191                 add_ptr_list(&to_vsl, clone_vs);
 192         } END_FOR_EACH_PTR(tmp);
 193         return to_vsl;
 194 }
 195
 196 void merge_var_sym_list(struct var_sym_list **dest, struct var_sym_list *src)
 197 {
 198         struct var_sym *tmp;
 199
 200         FOR_EACH_PTR(src, tmp) {
 201                 add_var_sym(dest, tmp->var, tmp->sym);
 202         } END_FOR_EACH_PTR(tmp);
 203 }
 204
 205 struct var_sym_list *combine_var_sym_lists(struct var_sym_list *one, struct var_sym_list *two)
 206 {
 207         struct var_sym_list *to_vsl;
 208
 209         to_vsl = clone_var_sym_list(one);
 210         merge_var_sym_list(&to_vsl, two);
 211         return to_vsl;
 212 }
 213
 214 int var_sym_lists_equiv(struct var_sym_list *one, struct var_sym_list *two)
 215 {
 216         struct var_sym *one_tmp, *two_tmp;
 217
 218         if (one == two)
 219                 return 1;
 220
 221         if (ptr_list_size((struct ptr_list *)one) != ptr_list_size((struct ptr_list *)two))
 222                 return 0;
 223
 224         PREPARE_PTR_LIST(one, one_tmp);
 225         PREPARE_PTR_LIST(two, two_tmp);
 226         for (;;) {
 227                 if (!one_tmp && !two_tmp)
 228                         return 1;
 229                 if (one_tmp->sym != two_tmp->sym)
 230                         return 0;
 231                 if (strcmp(one_tmp->var, two_tmp->var) != 0)
 232                         return 0;
 233                 NEXT_PTR_LIST(one_tmp);
 234                 NEXT_PTR_LIST(two_tmp);
 235         }
 236         FINISH_PTR_LIST(two_tmp);
 237         FINISH_PTR_LIST(one_tmp);
 238
 239         return 1;
 240 }
 241
 242 void free_var_sym_list(struct var_sym_list **list)
 243 {
 244         __free_ptr_list((struct ptr_list **)list);
 245 }
 246
 247 void free_var_syms_and_list(struct var_sym_list **list)
 248 {
 249         struct var_sym *tmp;
 250
 251         FOR_EACH_PTR(*list, tmp) {
 252                 free_var_sym(tmp);
 253         } END_FOR_EACH_PTR(tmp);
 254         free_var_sym_list(list);
 255 }
 256